82 results on '"Reni Kalfin"'
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2. Behavioral and Biochemical Effects of an Arylhydrazone Derivative of 5-Methoxyindole-2-Carboxylic Acid in a Scopolamine-Induced Model of Alzheimer’s Type Dementia in Rats
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Polina Petkova-Kirova, Neda Anastassova, Borislav Minchev, Diamara Uzunova, Valya Grigorova, Elina Tsvetanova, Almira Georgieva, Albena Alexandrova, Miroslava Stefanova, Denitsa Yancheva, Reni Kalfin, and Lyubka Tancheva
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Alzheimer’s disease ,arylhydrazone derivatives of 5-methoxyindole-2-carboxylic acid ,scopolamine ,step-through ,Barnes maze ,acetylcholine ,Organic chemistry ,QD241-441 - Abstract
Alzheimer’s disease (AD) has long proven to be a complex neurodegenerative disorder, with cholinergic dysfunction, oxidative stress, and neuroinflammation being just a few of its pathological features. The complexity of the disease requires a multitargeted treatment covering its many aspects. In the present investigation, an arylhydrazone derivative of 5-methoxyindole-2-carboxylic acid (5MeO), with in vitro strong antioxidant, neuroprotective and monoamine oxidase B-inhibiting effects, was studied in a scopolamine-induced Alzheimer-type dementia in rats. Using behavioral and biochemical methods, we evaluated the effects of 5MeO on learning and memory, and elucidated the mechanisms of these effects. Our experiments demonstrated that 5MeO had a beneficial effect on different types of memory as assessed by the step-through and the Barnes maze tasks. It efficiently restored the decreased by scopolamine brain-derived neurotrophic factor and acetylcholine levels and normalized the increased by scopolamine acetylcholine esterase activity in hippocampus. Most effective 5MeO was in counteracting the induced by scopolamine oxidative stress by decreasing the increased by scopolamine levels of lipid peroxidation and by increasing the reduced by scopolamine catalase activity. Blood biochemical analyses demonstrated a favorable safety profile of 5MeO, prompting further pharmacological studies suggesting 5MeO as a safe and efficient candidate in a multitargeted treatment of AD.
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- 2024
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3. Key Proteins in Rat Cerebral Cortex: Application of Cornu aspersum Extract as a Neuroprotective Agent in Alzheimer’s Type Dementia
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Ventseslav Atanasov, Lyudmila Velkova, Lyubka Tancheva, Aleksandar Dolashki, Reni Kalfin, and Pavlina Dolashka
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Alzheimer’s disease ,scopolamine ,snail extract ,neuroprotection ,brain proteins ,dementia ,Organic chemistry ,QD241-441 - Abstract
Alzheimer’s disease (AD) is the most widespread neurodegenerative disorder. Recently, it was found that mucus extract from Cornu aspersum has beneficial effects on memory and cognitive processes in a rat scopolamine model of AD. The present study elucidated the mechanisms of action of standardized mucus snail extract (SE) enriched with a fraction above 20 kDa on Alzheimer-type dementia in rats. Using proteomic analysis on two-dimensional polyacrylamide gel electrophoresis (2D–PAGE) on rat cortex extracts, we compared protein expression in both groups: the first group was treated intraperitoneally with scopolamine (Sco, 2 mg/kg, 11 days) and the second (Sco + SE) group was treated intraperitoneally with Sco (Sco, 2 mg/kg) and protected by SE (0.5 mL/100 g bw) applied daily orally for 11 days. Brain cortex was separated and the expressions of various proteins related to memory and cognitive functions were identified. We found that the expression of Ubiquitin carboxyl-terminal hydrolase isozyme L1, Calbindin, Vacuolar ATP synthase catalytic subunit A, Tropomyosin beta chain, 14-3-3 zeta/delta, Kinesin-1 heavy chain, and Stathmin-4 significantly differs in SE-protected rats as compared to dement animals treated only by Sco, and these brain proteins might be potential therapeutic targets for Alzheimer’s-type dementia treatment.
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- 2024
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4. Zeolite and Neurodegenerative Diseases
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Stefan Panaiotov, Lyubka Tancheva, Reni Kalfin, and Polina Petkova-Kirova
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zeolite ,clinoptilolite ,Alzheimer’s disease ,Parkinson’s disease ,detoxifying ,anti-inflammatory ,Organic chemistry ,QD241-441 - Abstract
Neurodegenerative diseases (NDs), characterized by progressive degeneration and death of neurons, are strongly related to aging, and the number of people with NDs will continue to rise. Alzheimer’s disease (AD) and Parkinson’s disease (PD) are the most common NDs, and the current treatments offer no cure. A growing body of research shows that AD and especially PD are intricately related to intestinal health and the gut microbiome and that both diseases can spread retrogradely from the gut to the brain. Zeolites are a large family of minerals built by [SiO4]4− and [AlO4]5− tetrahedrons joined by shared oxygen atoms and forming a three-dimensional microporous structure holding water molecules and ions. The most widespread and used zeolite is clinoptilolite, and additionally, mechanically activated clinoptilolites offer further improved beneficial effects. The current review describes and discusses the numerous positive effects of clinoptilolite and its forms on gut health and the gut microbiome, as well as their detoxifying, antioxidative, immunostimulatory, and anti-inflammatory effects, relevant to the treatment of NDs and especially AD and PD. The direct effects of clinoptilolite and its activated forms on AD pathology in vitro and in vivo are also reviewed, as well as the use of zeolites as biosensors and delivery systems related to PD.
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- 2024
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5. Visualization of the individual blood microbiome to study the etiology of sarcoidosis
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Yordan Hodzhev, Borislava Tsafarova, Vladimir Tolchkov, Vania Youroukova, Silvia Ivanova, Dimitar Kostadinov, Nikolay Yanev, Maya Zhelyazkova, Stefan Tsonev, Reni Kalfin, and Stefan Panaiotov
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Lung diseases ,Sarcoidosis ,Microbiome ,Metagenome analysis ,Visualization ,Sankey diagram ,Biotechnology ,TP248.13-248.65 - Abstract
Introduction: Single microbial pathogens or host-microbiome dysbiosis are the causes of lung diseases with suspected infectious etiology. Metagenome sequencing provides an overview of the microbiome content. Due to the rarity of most granulomatous lung diseases collecting large systematic datasets is challenging. Thus, single-patient data often can only be summarized visually. Objective: To increase the information gain from a single-case metagenome analysis we suggest a quantitative and qualitative approach. Results: The 16S metagenomic results of 7 patients with pulmonary sarcoidosis were compared with those of 22 healthy individuals. From lysed blood, total microbial DNA was extracted and sequenced. Cleaned data reads were identified taxonomically using Kraken 2 software. Individual metagenomic data were visualized with a Sankey diagram, Krona chart, and a heat-map. We identified five genera that were exclusively present or significantly enhanced in patients with sarcoidosis - Veillonella, Prevotella, Cutibacterium, Corynebacterium, and Streptococcus. Conclusions: Our approach can characterize the blood microbiome composition and diversity in rare diseases at an individual level. Investigation of the blood microbiome in patients with granulomatous lung diseases of unknown etiology, such as sarcoidosis could enhance our comprehension of their origin and pathogenesis and potentially uncover novel personalized therapeutics.
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- 2023
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6. Renal mitochondrial restoration by gymnemic acid in gentamicin-mediated experimental nephrotoxicity: evidence from serum, kidney and histopathological alterations
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Shubhangi Gumbar, Sudeep Bhardwaj, Sidharth Mehan, Zuber Khan, Acharan S. Narula, Reni Kalfin, Shams Tabrez, Torki A. Zughaibi, and Samina Wasi
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nephrotoxicity ,mitochondrial dysfunction ,antioxidant ,gymnemic acid ,nephroprotection ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Background: Nephrotoxicity refers to the toxigenic impact of compounds and medications on kidney function. There are a variety of drug formulations, and some medicines that may affect renal function in multiple ways via nephrotoxins production. Nephrotoxins are substances that are harmful to the kidneys.Purpose: This investigation examines the renoprotective effect of gymnemic acid (GA) on Wistar rats in gentamicin-induced nephrotoxicity by analyzing serum, kidney, and histopathological markers.Study-design/methods: The current study investigated the protective effect of GA at doses of 20, 40, and 60 mg/kg against gentamicin-induced nephrotoxicity in rats. Vitamin E was administered to compare the antioxidant capacity and efficacy of GA. In addition to the treatment groups, 100 mg/kg of gentamicin was administered intraperitoneal for 14 days. At the end of the study protocol, kidney homogenate, blood, and serum were evaluated biochemically. Serum creatinine, blood urea, glomerular filtration rate (GFR), mitochondrial dysfunctions, inflammatory cytokines, and renal oxidative stress were examined to assess gentamicin-induced nephrotoxicity. In addition, the impact of GA on the above-mentioned nephrotoxic markers were evaluated and further confirmed by histological analysis.Results: This study establishes a correlation between antibiotic use, especifically aminoglycosides and acute renal failure. The research demonstrates the nephrotoxic effects of aminoglycosides, inducing mitochondrial ETC-complex dysfunction, and renal tissue inflammation in experimental rats. GA’s antioxidant properties restored renal oxidative stress markers, reducing kidney inflammation and injury. Histopathological analysis revealed a significant reduction in renal injury with GA treatment. Additionally, GA demonstrated greater efficacy than Vitamin E in restoring antioxidant potential and mitochondrial enzymes.Conclusion: Consequently, our findings imply that long-term use of GA may be a suitable therapeutic strategy for reducing aminoglycoside toxicity. The current study suggests GA’s potential in treating gentamicin-induced nephrotoxicity and acute renal failure, meriting further investigation using advanced techniques.
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- 2023
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7. Emerging Therapeutic Potential of Polyphenols from Geranium sanguineum L. in Viral Infections, Including SARS-CoV-2
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Silviya Abarova, Ralitza Alexova, Stela Dragomanova, Ayten Solak, Paolo Fagone, Katia Mangano, Maria Cristina Petralia, Ferdinando Nicoletti, Reni Kalfin, and Lyubka Tancheva
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Geranium sanguineum ,viral infection ,COVID-19 ,poliphenols ,Microbiology ,QR1-502 - Abstract
The existing literature supports the anti-inflammatory, antioxidant, and antiviral capacities of the polyphenol extracts derived from Geranium sanguineum L. These extracts exhibit potential in hindering viral replication by inhibiting enzymes like DNA polymerase and reverse transcriptase. The antiviral properties of G. sanguineum L. seem to complement its immunomodulatory effects, contributing to infection resolution. While preclinical studies on G. sanguineum L. suggest its potential effectiveness against COVID-19, there is still a lack of clinical evidence. Therefore, the polyphenols extracted from this herb warrant further investigation as a potential alternative for preventing and treating COVID-19 infections.
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- 2024
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8. Morphology of blood microbiota in healthy individuals assessed by light and electron microscopy
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Borislava Tsafarova, Yordan Hodzhev, Georgi Yordanov, Vladimir Tolchkov, Reni Kalfin, and Stefan Panaiotov
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blood microbiota ,TEM ,SEM ,microscopy ,morphology ,proliferation cycle ,Microbiology ,QR1-502 - Abstract
IntroductionThe blood microbiome is still an enigma. The existence of blood microbiota in clinically healthy individuals was proven during the last 50 years. Indirect evidence from radiometric analysis suggested the existence of living microbial forms in erythrocytes. Recently targeted nucleic acid sequencing demonstrated rich microbial biodiversity in the blood of clinically healthy individuals. The morphology and proliferation cycle of blood microbiota in peripheral blood mononuclear cells (PBMC) isolated from freshly drawn and cultured whole blood are obscure.MethodsTo study the life cycle of blood microbiota we focused on light, and electron microscopy analysis. Peripheral blood mononuclear cells isolated from freshly drawn blood and stress-cultured lysed whole blood at 43°C in presence of vitamin K from healthy individuals were studied.ResultsHere, we demonstrated that free circulating microbiota in the PMBC fraction possess a well-defined cell wall and proliferate by budding or through a mechanism similar to the extrusion of progeny bodies. By contrast, stress-cultured lysed whole blood microbiota proliferated as cell-wall deficient microbiota by forming electron-dense or electron-transparent bodies. The electron-dense bodies proliferated by fission or produce in chains Gram-negatively stained progeny cells or enlarged and burst to release progeny cells of 180 – 200 nm size. On the other hand, electron-transparent bodies enlarged and emitted progeny cells through the membrane. A novel proliferation mechanism of blood microbiota called by us “a cell within a cell” was observed. It combines proliferation of progeny cells within a progeny cell which is growing within the “mother” cell.DiscussionThe rich biodiversity of eukaryotic and prokaryotic microbiota identified in blood by next-generation sequencing technologies and our microscopy results suggest different proliferation mechanisms in whole and cultured blood. Our documented evidence and conclusions provide a more comprehensive view of the existence of normal blood microbiota in healthy individuals.
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- 2023
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9. Memory Recovery Effect of a New Bioactive Innovative Combination in Rats with Experimental Dementia
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Lyubka Tancheva, Reni Kalfin, Borislav Minchev, Diamara Uzunova, Krasimira Tasheva, Elina Tsvetanova, Almira Georgieva, Albena Alexandrova, Miroslava Stefanova, Ayten Solak, Maria Lazarova, Yordan Hodzhev, Valya Grigorova, Dobri Yarkov, and Polina Petkova-Kirova
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Alzheimer’s disease ,α-lipoic acid ,citicoline ,extract of leaves green tea ,extract of leaves olive tree ,vitamin D3 ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Alzheimer’s disease manifests as a complex pathological condition, with neuroinflammation, oxidative stress and cholinergic dysfunction being a few of the many pathological changes. Due to the complexity of the disease, current therapeutic strategies aim at a multitargeted approach, often relying on a combination of substances with versatile and complementary effects. In the present study, a unique combination of α-lipoic acid, citicoline, extracts of leaves from olive tree and green tea, vitamin D3, selenium and an immune-supporting complex was tested in scopolamine-induced dementia in rats. Using behavioral and biochemical methods, we assessed the effects of the combination on learning and memory, and elucidated the mechanisms of these effects. Our results showed that, compared to its components, the experimental combination was most efficient in improving short- and long-term memory as assessed by the step-through method as well as spatial memory as assessed by T-maze and Barnes maze underlined by decreases in AChE activity (p < 0.05) and LPO (p < 0.001), increases in SOD activity in the cortex (p < 0.05) and increases in catalase (p < 0.05) and GPx (p < 0.01) activities and BDNF (p < 0.001) and pCREB (p < 0.05) levels in the hippocampus. No significant histopathological changes or blood parameter changes were detected, making the experimental combination an effective and safe candidate in a multitargeted treatment of AD.
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- 2023
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10. Therapeutic Potential of Myrtenal and Its Derivatives—A Review
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Stela Dragomanova, Velichka Andonova, Konstantin Volcho, Nariman Salakhutdinov, Reni Kalfin, and Lyubka Tancheva
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monoterpene ,pharmacophore ,chemical modification ,antiviral ,anticancer ,anxiolytic ,Science - Abstract
The investigation of monoterpenes as natural products has gained significant attention in the search for new pharmacological agents due to their ability to exhibit a wide range in biological activities, including antifungal, antibacterial, antioxidant, anticancer, antispasmodic, hypotensive, and vasodilating properties. In vitro and in vivo studies reveal their antidepressant, anxiolytic, and memory-enhancing effects in experimental dementia and Parkinson’s disease. Chemical modification of natural substances by conjugation with various synthetic components is a modern method of obtaining new biologically active compounds. The discovery of new potential drugs among monoterpene derivatives is a progressive avenue within experimental pharmacology, offering a promising approach for the therapy of diverse pathological conditions. Biologically active substances such as monoterpenes, for example, borneol, camphor, geraniol, pinene, and thymol, are used to synthesize compounds with analgesic, anti-inflammatory, anticonvulsive, antidepressant, anti-Alzheimer’s, antiparkinsonian, antiviral and antibacterial (antituberculosis) properties. Myrtenal is a perspective monoterpenoid with therapeutic potential in various fields of medicine. Its chemical modifications often lead to new or more pronounced biological effects. As an example, the conjugation of myrtenal with the established pharmacophore adamantane enables the augmentation of several of its pivotal properties. Myrtenal–adamantane derivatives exhibited a variety of beneficial characteristics, such as antimicrobial, antifungal, antiviral, anticancer, anxiolytic, and neuroprotective properties, which are worth examining in more detail and at length.
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- 2023
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11. Anti-COVID-19 Potential of Ellagic Acid and Polyphenols of Punica granatum L.
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Ralitza Alexova, Simona Alexandrova, Stela Dragomanova, Reni Kalfin, Ayten Solak, Sidharth Mehan, Maria Cristina Petralia, Paolo Fagone, Katia Mangano, Ferdinando Nicoletti, and Lyubka Tancheva
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Punica granatum ,COVID-19 ,polyphenols ,ellagitannins ,ellagic acid ,Organic chemistry ,QD241-441 - Abstract
Pomegranate (Punica granatum L.) is a rich source of polyphenols, including ellagitannins and ellagic acid. The plant is used in traditional medicine, and its purified components can provide anti-inflammatory and antioxidant activity and support of host defenses during viral infection and recovery from disease. Current data show that pomegranate polyphenol extract and its ellagitannin components and metabolites exert their beneficial effects by controlling immune cell infiltration, regulating the cytokine secretion and reactive oxygen and nitrogen species production, and by modulating the activity of the NFκB pathway. In vitro, pomegranate extracts and ellagitannins interact with and inhibit the infectivity of a range of viruses, including SARS-CoV-2. In silico docking studies show that ellagitannins bind to several SARS-CoV-2 and human proteins, including a number of proteases. This warrants further exploration of polyphenol–viral and polyphenol–host interactions in in vitro and in vivo studies. Pomegranate extracts, ellagitannins and ellagic acid are promising agents to target the SARS-CoV-2 virus and to restrict the host inflammatory response to viral infections, as well as to supplement the depleted host antioxidant levels during the stage of recovery from COVID-19.
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- 2023
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12. Beta-Boswellic Acid Reverses 3-Nitropropionic Acid-Induced Molecular, Mitochondrial, and Histopathological Defects in Experimental Rat Model of Huntington’s Disease
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Thamer H. Albekairi, Arzoo Kamra, Sudeep Bhardwaj, Sidharth Mehan, Aditi Giri, Manisha Suri, Abdulrahman Alshammari, Metab Alharbi, Abdullah F. Alasmari, Acharan S Narula, and Reni Kalfin
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β-Boswellic acid (β-BA) ,Huntington’s disease (HD) ,mitochondrial ETC-complexes ,3-nitropropionic acid (3-NP) ,neuroprotection ,Biology (General) ,QH301-705.5 - Abstract
Huntington’s disease (HD) is distinguished by a triple repeat of CAG in exon 1, an increase in poly Q in the Htt gene, and a loss of GABAergic medium spiny neurons (MSN) in the striatum and white matter of the cortex. Mitochondrial ETC-complex dysfunctions are involved in the pathogenesis of HD, including neuronal energy loss, synaptic neurotrophic decline, neuronal inflammation, apoptosis, and grey and white matter destruction. A previous study has demonstrated that beta Boswellic acid (β-BA), a naturally occurring phytochemical, has several neuroprotective properties that can reduce pathogenic factors associated with various neurological disorders. The current investigation aimed to investigate the neuroprotective potential of β-BA at oral doses of 5, 10, and 15 mg/kg alone, as well as in conjunction with the potent antioxidant vitamin E (8 mg/kg, orally) in 3-NP-induced experimental HD rats. Adult Wistar rats were separated into seven groups, and 3-NP, at a dose of 10 mg/kg, was orally administered to each group of adult Wistar rats beginning on day 1 and continuing through day 14. The neurotoxin 3-NP induces neurodegenerative, g, neurochemical, and pathological alterations in experimental animals. Continuous injection of 3-NP, according to our results, aggravated HD symptoms by suppressing ETC-complex-II, succinate dehydrogenase activity, and neurochemical alterations. β-BA, when taken with vitamin E, improved behavioural dysfunctions such as neuromuscular and motor impairments, as well as memory and cognitive abnormalities. Pharmacological treatments with β-BA improved and restored ETC complexes enzymes I, II, and V levels in brain homogenates. β-BA treatment also restored neurotransmitter levels in the brain while lowering inflammatory cytokines and oxidative stress biomarkers. β-BA’s neuroprotective potential in reducing neuronal death was supported by histopathological findings in the striatum and cortex. As a result, the findings of this research contributed to a better understanding of the potential role of natural phytochemicals β-BA in preventing neurological illnesses such as HD.
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- 2022
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13. Effect of Natural Adenylcyclase/cAMP/CREB Signalling Activator Forskolin against Intra-Striatal 6-OHDA-Lesioned Parkinson’s Rats: Preventing Mitochondrial, Motor and Histopathological Defects
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Metab Alharbi, Abdulrahman Alshammari, Gurpreet Kaur, Sanjeev Kalra, Sidharth Mehan, Manisha Suri, Swesha Chhabra, Nitish Kumar, Wael A. Alanazi, Aliah R. Alshanwani, Abdullah Hamed AL-Ghamdi, Acharan S. Narula, and Reni Kalfin
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adenylcyclase ,CREB ,forskolin ,mitochondrial abnormalities ,Parkinson’s disease ,Organic chemistry ,QD241-441 - Abstract
Parkinson’s disease (PD) is characterised by dopaminergic neuronal loss in the brain area. PD is a complex disease that deteriorates patients’ motor and non-motor functions. In experimental animals, the neurotoxin 6-OHDA induces neuropathological, behavioural, neurochemical and mitochondrial abnormalities and the formation of free radicals, which is related to Parkinson-like symptoms after inter-striatal 6-OHDA injection. Pathological manifestations of PD disrupt the cAMP/ATP-mediated activity of the transcription factor CREB, resulting in Parkinson’s-like symptoms. Forskolin (FSK) is a direct AC/cAMP/CREB activator isolated from Coleus forskohlii with various neuroprotective properties. FSK has already been proven in our laboratory to directly activate the enzyme adenylcyclase (AC) and reverse the neurodegeneration associated with the progression of Autism, Multiple Sclerosis, ALS, and Huntington’s disease. Several behavioural paradigms were used to confirm the post-lesion effects, including the rotarod, open field, grip strength, narrow beam walk (NBW) and Morris water maze (MWM) tasks. Our results were supported by examining brain cellular, molecular, mitochondrial and histopathological alterations. The FSK treatment (15, 30 and 45 mg/kg, orally) was found to be effective in restoring behavioural and neurochemical defects in a 6-OHDA-induced experimental rat model of PD. As a result, the current study successfully contributes to the investigation of FSK’s neuroprotective role in PD prevention via the activation of the AC/cAMP/PKA-driven CREB pathway and the restoration of mitochondrial ETC-complex enzymes.
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- 2022
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14. Gene Co-Expression Network Modular Analysis Reveals Altered Immune Mechanisms in HIV-HAND
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Maria Cristina Petralia, Ferdinando Nicoletti, Lyubka Tancheva, Reni Kalfin, Paolo Fagone, and Katia Mangano
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HIV ,HIV-HAND ,HIV-HAD ,HIVE neurocognitive impairment ,immune response ,National NeuroAIDS Tissue Consortium ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Although the introduction of HAART has completely changed the natural course of HIV infection, the number of chronic forms of HIV-associated neurocognitive disorder (HAND) has risen. It is estimated that up to half of subjects undergoing HAART therapy exhibit mild cognitive impairments. In the current study, we apply the gene co-expression network modular analysis, a well-established system biology approach, to the gene expression profiles of cases from the National NeuroAIDS Tissue Consortium (NNTC). We observed a negative enrichment for genes associated with the control of immune responses and putatively regulated by the transcription factors IRF8 and SPI1 and by both type I and II interferons. Our study provides evidence of altered immune responses, which are likely associated with the occurrence of HAND in the absence of HIV encephalitis (HIVE).
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- 2022
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15. Synthesis, Molecular Docking, and Neuroprotective Effect of 2-Methylcinnamic Acid Amide in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)—An Induced Parkinson’s Disease Model
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Maya Chochkova, Rusi Rusew, Reni Kalfin, Lyubka Tancheva, Maria Lazarova, Hristina Sbirkova-Dimitrova, Andrey Popatanasov, Krasimira Tasheva, Boris Shivachev, Nejc Petek, and Martin Štícha
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amantadine ,2-methylcinnamic acid ,single crystal X-ray diffraction ,Parkinson’s disease ,Crystallography ,QD901-999 - Abstract
Parkinson’s disease (PD) has emerged as the second most common form of human neurodegenerative disorders. However, due to the severe side effects of the current antiparkinsonian drugs, the design of novel and safe compounds is a hot topic amongst the medicinal chemistry community. Herein, a convenient peptide method, TBTU (O-(benzotriazole-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate), was used for the synthesis of the amide (E)-N-(2-methylcinnamoyl)-amantadine (CA(2-Me)-Am; 3)) derived from amantadine and 2-methylcinnamic acid. The obtained hybrid was studied for its antiparkinsonian activity in an experimental model of PD induced by MPTP. Mice (C57BL/6,male, 8 weeks old) were divided into four groups as follows: (1) the control, treated with normal saline (i.p.) for 12 consecutive days; (2) MPTP (30 mg/kg/day, i.p.), applied daily for 5 consecutive days; (3) MPTP + CA(2-Me)-Am, applied for 12 consecutive days, 5 days simultaneously with MPTP and 7 days after MPTP; (4) CA(2-Me)-Am +oleanoic acid (OA), applied daily for 12 consecutive days. Neurobehavioral parameters in all experimental groups of mice were evaluated by rotarod test and passive avoidance test. Our experimental data showed that CA(2-Me)-Am in parkinsonian mice significantly restored memory performance, while neuromuscular coordination approached the control level, indicating the ameliorating effects of the new compound. In conclusion, the newly synthesized hybrid might be a promising agent for treating motor disturbances and cognitive impairment in experimental PD.
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- 2022
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16. Forskolin, an Adenylcyclase/cAMP/CREB Signaling Activator Restoring Myelin-Associated Oligodendrocyte Destruction in Experimental Ethidium Bromide Model of Multiple Sclerosis
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Tarun Kapoor, Sidharth Mehan, Manisha Suri, Nidhi Sharma, Nitish Kumar, Acharan S. Narula, Abdulrahman Alshammari, Abdullah F. Alasmari, Metab Alharbi, Mohammed A. Assiri, and Reni Kalfin
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adenylcyclase ,demyelination ,Ethidium Bromide ,Forskolin ,multiple sclerosis ,Cytology ,QH573-671 - Abstract
Multiple sclerosis (MS) is a chronic neurodegenerative disease marked by oligodendrocyte loss, which results in central neuronal demyelination. AC/cAMP/CREB signaling dysregulation is involved in the progression of MS, including mitochondrial dysfunctions, reduction in nerve growth factors, neuronal inflammation, apoptosis, and white matter degeneration. Our previous research has shown that Forskolin (FSK), a naturally occurring direct adenylyl cyclase (AC)/cAMP/CREB activator, has neuroprotective potential to alleviate pathogenic factors linked with numerous neurological abnormalities. The current study intends to explore the neuroprotective potential of FSK at doses of 40 mg/kg and 60 mg/kg alone, as well as in combination with conventional medicines, such as Fingolimod (FNG), Donepezil (DON), Memantine (MEM), and Simvastatin (SIM) in EB-induced demyelinated experimental MS rats. Adult Wistar rats were divided into nine groups, and EB was infused stereotaxically in the rat brain’s intracerebropeduncle (ICP) area. Chronic gliotoxin EB treatment results in demyelination as well as motor and cognitive dysfunctions. FSK, combined with standard medications, improves behavioral dysfunctions, such as neuromuscular and motor deficits and memory and cognitive abnormalities. Following pharmacological treatments improved remyelination by enhancing myelin basic protein and increasing AC, cAMP, and CREB levels in brain homogenates. Furthermore, FSK therapy restored brain mitochondrial-ETC complex enzymes and neurotransmitter levels while decreasing inflammatory cytokines and oxidative stress markers. The Luxol fast blue (LFB) stain results further indicate FSK’s neuroprotective potential in preventing oligodendrocyte death. Therefore, the results of these studies contribute to a better understanding of the possible role that natural phytochemicals FSK could have in preventing motor neuron diseases, such as multiple sclerosis.
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- 2022
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17. New Myrtenal–Adamantane Conjugates Alleviate Alzheimer’s-Type Dementia in Rat Model
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Stela Dragomanova, Maria Lazarova, Aldar Munkuev, Evgeniy Suslov, Konstantin Volcho, Nariman Salakhutdinov, Amina Bibi, Jóhannes Reynisson, Elina Tzvetanova, Albena Alexandrova, Almira Georgieva, Diamara Uzunova, Miroslava Stefanova, Reni Kalfin, and Lyubka Tancheva
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neuroprotection ,experimental dementia ,myrtenal–adamantane conjugates ,acetylcholinesterase ,monoamines ,memory ,Organic chemistry ,QD241-441 - Abstract
Alzheimer’s disease (AD) is a neurodegenerative disease associated with memory impairment and other central nervous system (CNS) symptoms. Two myrtenal–adamantane conjugates (MACs) showed excellent CNS potential against Alzheimer’s models. Adamantane is a common pharmacophore for drug design, and myrtenal (M) demonstrated neuroprotective effects in our previous studies. The aim of this study is to evaluate the MACs’ neuroprotective properties in dementia. Methods: Scopolamine (Scop) was applied intraperitoneally in Wistar rats for 11 days, simultaneously with MACs or M as a referent, respectively. Brain acetylcholine esterase (AChE) activity, noradrenaline and serotonin levels, and oxidative brain status determination followed behavioral tests on memory abilities. Molecular descriptors and docking analyses for AChE activity center affinity were performed. Results: M derivatives have favorable physicochemical parameters to enter the CNS. Both MACs restored memory damaged by Scop, showing significant AChE-inhibitory activity in the cortex, in contrast to M, supported by the modeling analysis. Moderate antioxidant properties were manifested by glutathione elevation and catalase activity modulation. MACs also altered noradrenaline and serotonin content in the hippocampus. Conclusion: For the first time, neuroprotective properties of two MACs in a rat dementia model were observed. They were stronger than the natural M effects, which makes the substances promising candidates for AD treatment.
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- 2022
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18. Development of N,N-Dimethylglycine-Amantadine for Adjunctive Dopaminergic Application: Synthesis, Structure and Biological Activity
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Radoslav Chayrov, Reni Kalfin, Maria Lazarova, Lyubka Tancheva, Hrisitna Sbirkova-Dimitrova, Boris Shivachev, and Ivanka Stankova
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amantadine ,N,N-dimethylglycine ,Parkinson disease ,neuroprotective ,dyskinesias ,Crystallography ,QD901-999 - Abstract
N-methyl-D-aspartate (NMDA) receptor blockade can improve L-DOPA (l-3,4-dihydroxyphenylalanine)-induced dyskinesias in Parkinson’s disease (PD) patients. Amantadine is a well-tolerated and effective antiparkinsonian agent, recently found to possess NMDA antagonistic properties. Oxidative damage may contribute to dopaminergic (DAergic) neurodegeneration in the substantia nigra of patients with PD. N,N-dimethylglycine (DMG) (also known as vitamin B15 or pangamic acid) acts as an antioxidant, extending the lifespan of animal cells through protection from oxidation. In this study, we synthesized and tested in vivo the newly obtained compound N,N-dimethylglycine-amantadine (DMG-Am) for antiparkinsonian activity. MPTP (1-methyl-4–phenyl-1, 2, 3, 6-tetrahydropyridine) is a widely used neurotoxin to induce an experimental model which mimics Parkinson disease-like symptoms. The neuroprotective capacity of the new amantadine derivative DMG-Am was evaluated by its potential to ameliorate the neuromuscular coordination and behavioral changes worsened by the toxin. Our experimental results showed that DMG-Am applied for 12 consecutive days, 5 days simultaneously and 7 days after MPTP, restored motor and memory performance of the animals to the control level, indication of beneficial protective effect of this compound. In summary, our results reveal the potential of newly synthesized DMG-Am as promising antiparkinsonian agent.
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- 2022
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19. Activating SIRT-1 Signalling with the Mitochondrial-CoQ10 Activator Solanesol Improves Neurobehavioral and Neurochemical Defects in Ouabain-Induced Experimental Model of Bipolar Disorder
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Bidisha Rajkhowa, Sidharth Mehan, Pranshul Sethi, Aradhana Prajapati, Manisha Suri, Sumit Kumar, Sonalika Bhalla, Acharan S. Narula, Abdulrahman Alshammari, Metab Alharbi, Nora Alkahtani, Saeed Alghamdi, and Reni Kalfin
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bipolar disorder ,lithium ,neuroprotection ,ouabain ,SIRT-1 ,solanesol ,Medicine ,Pharmacy and materia medica ,RS1-441 - Abstract
Bipolar disorder (BD) is a chronic mental illness characterized by mood fluctuations that range from depressive lows to manic highs. Several studies have linked the downregulation of SIRT-1 (silent mating type information regulation-2 homologs) signaling to the onset of BD and other neurological dysfunctions. This research aimed to look into the neuroprotective potential of Solanesol (SNL) in rats given ICV-Ouabain injections, focusing on its effect on SIRT-1 signaling activation in the brain. Ouabain, found in hypothalamic and medullary neurons, is an endogenous inhibitor of brain Na+/K+ ATPase. The inhibition of brain Na+/K+ ATPase by Ouabain may also result in changes in neurotransmission within the central nervous system. SNL is a Solanaceae family active phytoconstituent produced from the plant Nicotiana tabacum. SNL is used as a precursor for the production of CoQ10 (Coenzyme Q10), a powerful antioxidant and neuroprotective compound. In the current study, lithium (Li), an important mood stabilizer drug, was used as a control. This study looked at the neuroprotective potential of SNL at dosages of 40 and 80 mg/kg in ICV-OUA injections that caused BD-like neurobehavioral and neurochemical defects in Wistar rats. Wistar rats were placed into eight groups (n = 6) and administered 1 mM/0.5 µL ICV-OUA injections for three days. Neurochemical assessments were done in rat brain homogenates, CSF, and blood plasma samples at the end of the experiment protocol schedule. Long-term SNL and lithium administration have been shown to decrease the number of rearing and crossings and reduce time spent in the center, locomotor activities, and immobility time. Solansesol treatment gradually raises the amount of Na+/K+ ATPase, limiting the severity of behavioural symptoms. These findings also revealed that SNL increases the levels of SIRT-1 in CSF, blood plasma, and brain homogenate samples. Moreover, in rat brain homogenates and blood plasma samples, SNL modulates apoptotic markers such as Caspase-3, Bax (pro-apoptotic), and Bcl-2 (anti-apoptotic). Mitochondrial-ETC complex enzymes, including complex-I, II, IV, V, and CoQ10, were also restored following long-term SNL treatment. Furthermore, SNL lowered inflammatory cytokines (TNF-α, IL-1β) levels while restoring neurotransmitter levels (serotonin, dopamine, glutamate, and acetylcholine) and decreasing oxidative stress markers. Histological examinations also validated Solanesol’s protective effect. As a result, our findings suggest that SNL, as a SIRT-1 signalling activator, may be a promising therapeutic approach for BD-like neurological dysfunctions.
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- 2022
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20. Neuroprotective Effects of Myrtenal in an Experimental Model of Dementia Induced in Rats
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Stela Dragomanova, Stoyan Pavlov, Desislava Marinova, Yordan Hodzev, Maria Cristina Petralia, Paolo Fagone, Ferdinando Nicoletti, Maria Lazarova, Elina Tzvetanova, Albena Alexandrova, Reni Kalfin, and Lyubka Tancheva
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myrtenal ,experimental dementia ,acetylcholine ,acetylcholinesterase ,antioxidant ,neuroprotection ,Therapeutics. Pharmacology ,RM1-950 - Abstract
There is growing attention on natural substances capable of stimulating the cholinergic system and of exerting antioxidant effects, as potential therapeutic agents in Alzheimer’s disease (AD). The aim of the present study is to evaluate the expected neuroprotective mechanisms of myrtenal (M) in an experimental model of dementia in rats. Dementia was induced in male Wistar rats by scopolamine (Sc) administration (0.1 mg/kg for 8 days and 20.0 mg/kg on day 9). The animals were divided into 5 groups (1) Controls; (2) Sc; (3) Sc + Myrtenal (40 mg/kg), (4) Sc + Galantamine (1 mg/kg); (5) Sc + Lipoic acid (30 mg/kg). Changes in recognition memory and habituation were evaluated via the Novel Object Recognition and Open Field tests. Acetylcholinesterase (AChE) activity, ACh levels, and changes in oxidative status of the brain were measured biochemically. The histological changes in two brain regions—cortex and hippocampus, were evaluated qualitatively and quantitatively. Myrtenal improved recognition memory and habituation, exerted antioxidant effects and significantly increased ACh brain levels. Histologically, the neuroprotective capacity of myrtenal was also confirmed. For the first time, we have demonstrated the neuroprotective potential of myrtenal in an experimental model of dementia. Our study provides proof-of-concept for the testing of myrtenal, in association with standard of care treatments, in patients affected by cognitive decline.
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- 2022
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21. Culturable and Non-Culturable Blood Microbiota of Healthy Individuals
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Stefan Panaiotov, Yordan Hodzhev, Borislava Tsafarova, Vladimir Tolchkov, and Reni Kalfin
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blood microbiome ,metagenomics ,targeted sequencing ,Biology (General) ,QH301-705.5 - Abstract
Next-generation sequencing (NGS) and metagenomics revolutionized our capacity for analysis and identification of the microbial communities in complex samples. The existence of a blood microbiome in healthy individuals has been confirmed by sequencing, but some researchers suspect that this is a cell-free circulating DNA in blood, while others have had isolated a limited number of bacterial and fungal species by culture. It is not clear what part of the blood microbiota could be resuscitated and cultured. Here, we quantitatively measured the culturable part of blood microbiota of healthy individuals by testing a medium supplemented with a high concentration of vitamin K (1 mg/mL) and culturing at 43 °C for 24 h. We applied targeted sequencing of 16S rDNA and internal transcribed spacer (ITS) markers on cultured and non-cultured blood samples from 28 healthy individuals. Dominant bacterial phyla among non-cultured samples were Proteobacteria 92.97%, Firmicutes 2.18%, Actinobacteria 1.74% and Planctomycetes 1.55%, while among cultured samples Proteobacteria were 47.83%, Firmicutes 25.85%, Actinobacteria 16.42%, Bacteroidetes 3.48%, Cyanobacteria 2.74%, and Fusobacteria 1.53%. Fungi phyla Basidiomycota, Ascomycota, and unidentified fungi were 65.08%, 17.72%, and 17.2% respectively among non-cultured samples, while among cultured samples they were 58.08%, 21.72%, and 20.2% respectively. In cultured and non-cultured samples we identified 241 OTUs belonging to 40 bacterial orders comprising 66 families and 105 genera. Fungal biodiversity accounted for 272 OTUs distributed in 61 orders, 105 families, and 133 genera. Bacterial orders that remained non-cultured, compared to blood microbiota isolated from fresh blood collection, were Sphingomonadales, Rhizobiales, and Rhodospirillales. Species of orders Bacillales, Lactobacillales, and Corynebacteriales showed the best cultivability. Fungi orders Tremellales, Polyporales, and Filobasidiales were mostly unculturable. Species of fungi orders Pleosporales, Saccharomycetales, and Helotiales were among the culturable ones. In this study, we quantified the capacity of a specific medium applied for culturing of blood microbiota in healthy individuals. Other culturing conditions and media should be tested for optimization and better characterization of blood microbiota in healthy and diseased individuals.
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- 2021
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22. Emerging Neurological and Psychobiological Aspects of COVID-19 Infection
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Lyubka Tancheva, Maria Cristina Petralia, Simona Miteva, Stela Dragomanova, Ayten Solak, Reni Kalfin, Maria Lazarova, Dobri Yarkov, Rosella Ciurleo, Eugenio Cavalli, Alessia Bramanti, and Ferdinando Nicoletti
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COVID-19 ,cytokines ,central nervous system ,Neuro-COVID ,Parkinson’s disease ,peripheral nervous system ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
The SARS-CoV-2 virus, first reported in December 2019 in China, is the causative agent of the current COVID-19 pandemic that, at the time of writing (1 November 2020) has infected almost 43 million people and caused the death of more than 1 million people. The spectrum of clinical manifestations observed during COVID-19 infection varies from asymptomatic to critical life-threatening clinical conditions. Emerging evidence shows that COVID-19 affects far more organs than just the respiratory system, including the heart, kidneys, blood vessels, liver, as well as the central nervous system (CNS) and the peripheral nervous system (PNS). It is also becoming clear that the neurological and psychological disturbances that occur during the acute phase of the infection may persist well beyond the recovery. The aim of this review is to propel further this emerging and relevant field of research related to the pathophysiology of neurological manifestation of COVID-19 infection (Neuro-COVID). We will summarize the PNS and CNS symptoms experienced by people with COVID-19 both during infection and in the recovery phase. Diagnostic and pharmacological findings in this field of study are strongly warranted to address the neurological and psychological symptoms of COVID-19.
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- 2020
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23. Exploratory Analysis of iPSCS-Derived Neuronal Cells as Predictors of Diagnosis and Treatment of Alzheimer Disease
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Eugenio Cavalli, Giuseppe Battaglia, Maria Sofia Basile, Valeria Bruno, Maria Cristina Petralia, Salvo Danilo Lombardo, Manuela Pennisi, Reni Kalfin, Lyubka Tancheva, Paolo Fagone, Ferdinando Nicoletti, and Katia Mangano
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alzheimer disease ,induced pluripotent stem cells-derived neuronal cells ,drug repurposing ,biomarkers ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Alzheimer’s disease (AD) represents the most common neurodegenerative disorder, with 47 million affected people worldwide. Current treatment strategies are aimed at reducing the symptoms and do slow down the progression of the disease, but inevitably fail in the long-term. Induced pluripotent stem cells (iPSCs)-derived neuronal cells from AD patients have proven to be a reliable model for AD pathogenesis. Here, we have conducted an in silico analysis aimed at identifying pathogenic gene-expression profiles and novel drug candidates. The GSE117589 microarray dataset was used for the identification of Differentially Expressed Genes (DEGs) between iPSC-derived neuronal progenitor (NP) cells and neurons from AD patients and healthy donors. The Discriminant Analysis Module (DAM) algorithm was used for the identification of biomarkers of disease. Drugs with anti-signature gene perturbation profiles were identified using the L1000FWD software. DAM analysis was used to identify a list of potential biomarkers among the DEGs, able to discriminate AD patients from healthy people. Finally, anti-signature perturbation analysis identified potential anti-AD drugs. This study set the basis for the investigation of potential novel pharmacological strategies for AD. Furthermore, a subset of genes for the early diagnosis of AD is proposed.
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- 2020
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24. Beneficial Effects of Snail Helix aspersa Extract in an Experimental Model of Alzheimer’s Type Dementia
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Lyubka Tancheva, Maria Lazarova, Lyudmila Velkova, Alexander Dolashki, Diamara Uzunova, Borislav Minchev, Polina Petkova-Kirova, Yozljam Hassanova, Petja Gavrilova, Krasimira Tasheva, Teodora Taseva, Yordan Hodzhev, Atanas G. Atanasov, Miroslava Stefanova, Albena Alexandrova, Elina Tzvetanova, Ventseslav Atanasov, Reni Kalfin, and Pavlina Dolashka
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Male ,Memory Disorders ,Plant Extracts ,Brain-Derived Neurotrophic Factor ,General Neuroscience ,Scopolamine ,Neurodegenerative Diseases ,General Medicine ,Models, Theoretical ,Hippocampus ,Antioxidants ,Rats ,Psychiatry and Mental health ,Clinical Psychology ,Alzheimer Disease ,Acetylcholinesterase ,Animals ,Rats, Wistar ,Geriatrics and Gerontology ,Cyclic AMP Response Element-Binding Protein - Abstract
Background: Alzheimer’s disease (AD) is a complex neurodegenerative disease with multifactorial etiology, unsatisfactory treatment, and a necessity for broad-spectrum active substances for cure. The mucus from Helix aspersa snail is a mixture of bioactive molecules with antimicrobial, anti-inflammatory, antioxidant, and anti-apoptotic effects. So far there are no data concerning the capacity of snail extract (SE) to affect neurodegenerative disorders. Objective: The effects of SE from Helix aspersa on learning and memory deficits in Alzheimer’s type dementia (ATD) induced by scopolamine (Sco) in male Wistar rats were examined and some mechanisms of action underlying these effects were evaluated. Methods: SE (0.5 mL/100 g) was applied orally through a food tube for 16 consecutive days: 5 days before and 11 days simultaneously with Sco (2 mg/kg, intraperitoneally). At the end of Sco treatment, using behavioral methods, we evaluated memory performance. Additionally, in cortex and hippocampus the acetylcholinesterase (AChE) activity, acetylcholine and monoamines (dopamine, noradrenaline, and serotonin) content, levels of main oxidative stress markers, and expression of brain-derived neurotrophic factor (BDNF) and cAMP response element-binding protein (CREB) were determined. Results: We demonstrated that, according to all behavioral tests used, SE significantly improved the cognitive deficits induced by Sco. Furthermore, SE possessed AChE inhibitory activity, moderate antioxidant properties and the ability to modulate monoamines content in two brain structures. Moreover, multiple SE applications not only restored the depressed by Sco expression of CREB and BDNF, but significantly upregulated it. Conclusion: Summarizing results, we conclude that complex mechanisms underlie the beneficial effects of SE on impaired memory in Alzheimer’s type dementia.
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- 2022
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25. New Galantamine Derivatives with Inhibitory Effect on Acetylcholinesterase Activity
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Stela Dragomanova, Diamara Uzunova, Albena Alexandrova, Maria G. Papazova, Yordan Handzhiyski, Reni Kalfin, K. Kirilov, Lyubomir T. Vezenkov, Almira Georgieva, Maria Lazarova, L. Tancheva, D. Tsekova, Elina Tsvetanova, and Petja T. Gavrilova
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Male ,Antioxidant ,medicine.medical_treatment ,Pharmacology ,medicine.disease_cause ,Antioxidants ,Superoxide dismutase ,Lipid peroxidation ,Mice ,chemistry.chemical_compound ,Alzheimer Disease ,Memory ,medicine ,Galantamine ,Animals ,Humans ,chemistry.chemical_classification ,Glutathione Peroxidase ,Mice, Inbred ICR ,biology ,Superoxide Dismutase ,General Neuroscience ,Glutathione peroxidase ,Brain ,General Medicine ,Glutathione ,Catalase ,Acetylcholinesterase ,Oxidative Stress ,Psychiatry and Mental health ,Clinical Psychology ,chemistry ,biology.protein ,Cholinesterase Inhibitors ,Lipid Peroxidation ,Geriatrics and Gerontology ,Oxidative stress ,medicine.drug - Abstract
Background: Inhibitors of acetylcholinesterase (AChE) are used to treat many disorders, among which are neurodegenerative upsets, like Alzheimer’s disease (AD). One of the limited licensed AChE inhibitors (AChEIs) used as drugs is the natural compound galantamine (Gal). Objective: As Gal is a toxic compound, here we expose data about its four derivatives in hybrid peptide-norgalantamine molecules, which have shown 100 times lower toxicity. Methods: Four newly synthesized galantamine derivatives have been involved in docking analysis made by Molegro Virtual Docker. Biological assessments were performed on ICR male mice. The change in short and long-term memory performance was evaluated by passive avoidance test. AChE activity and levels of main oxidative stress parameters: lipid peroxidation, total glutathione (GSH), enzyme activities of catalase (CAT), superoxide dismutase, and glutathione peroxidase were measured in brain homogenates. Results: Our experimental data revealed that the new hybrid molecules did not impair memory performance in healthy mice. Two of the compounds demonstrated better than Gal AChE inhibitory activity in the brain. None of them changed the level of lipid peroxidation products, one of the compounds increased GSH levels, and all of them increased CAT enzyme activity. Conclusion: The new galantamine-peptide hybrids demonstrated a potential for inhibition of AChE and antioxidant activity and deserve further attention.
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- 2021
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26. Neurotensin(8–13) analogs as dual NTS1 and NTS2 receptor ligands with enhanced effects on a mouse model of Parkinson's disease
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Toni Kühl, Maya G. Georgieva, Harald Hübner, Maria Lazarova, Matthias Vogel, Bodo Haas, Martina I. Peeva, Aneliya A. Balacheva, Ivan P. Bogdanov, Luigi Milella, Maria Ponticelli, Tsvetomir Garev, Immacolata Faraone, Roumyana Detcheva, Borislav Minchev, Polina Petkova-Kirova, Lyubka Tancheva, Reni Kalfin, Atanas G. Atanasov, Liudmil Antonov, Tamara I. Pajpanova, Kiril Kirilov, Marcus Gastreich, Peter Gmeiner, Diana Imhof, and Nikolay T. Tzvetkov
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Pharmacology ,Organic Chemistry ,Drug Discovery ,General Medicine - Published
- 2023
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27. Tyrosinyl-amantadine: A New Amantadine Derivative With an Ameliorative Effect in a 6-OHDA Experimental Model of Parkinson's Disease in Rats
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Maria Lazarova, Lyubka Tancheva, Radoslav Chayrov, Elina Tzvetanova, Albena Alexandrova, Andrey Popatanasov, Diamara Uzunova, Miroslava Stefanova, Ivanka Stankova, and Reni Kalfin
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Male ,Parkinson's disease ,Parkinson Disease ,General Medicine ,Models, Theoretical ,Rats ,Antiparkinson Agents ,L-DOPA-induced dyskinesia ,Cellular and Molecular Neuroscience ,Disease Models, Animal ,Acetylcholinesterase ,Amantadine ,Animals ,Tyrosine ,Rats, Wistar ,Oxidopamine ,6-Hydroxydopamine - Abstract
The neuroprotective capacity of newly synthesized amantadine derivative tyrosinyl-amantadine (Tyr-Am) with expected antiparkinsonian properties was evaluated in a 6-hydroxydopamine (6-OHDA) model of Parkinson's disease. Male Wistar rats were divided into the following groups: sham-operated (SO), striatal 6-OHDA-lesioned control group, 6-OHDA-lesioned rats pretreated for 6 days with Tyr-Am (16 mg/kg administered intraperitoneally, i.p.), and 6-OHDA-lesioned rats pretreated for 6 days with amantadine (40 mg/kg i.p.), used as a referent. On the first, second and third week post-lesion, the animals were subjected to some behavioral tests (apomorphine-induced rotation, rotarod, and passive avoidance test). The acetylcholinesterase (AChE) activity and key oxidative stress parameters including lipid peroxidation levels (LPO) and superoxide dismutase (SOD) were measured in brain homogenates. The results showed that the neuroprotective effect of Tyr-Am was comparable to that of amantadine, improving neuromuscular coordination and learning and memory performance even at a 2.5-fold lower dose. Tyr-Am demonstrated significant antioxidant properties via decreased LPO levels but had no effect on AChE activity. We can conclude that the newly synthesized amantadine derivative Tyr-Am demonstrated significant antiparkinsonian activity in a 6-OHDA experimental model.
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- 2022
28. Preventive and Therapeutic Effects of Punica granatum L. Polyphenols in Neurological Conditions
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Simona Aleksandrova, Ralitza Alexova, Stela Dragomanova, Reni Kalfin, Ferdinando Nicoletti, Paolo Fagone, Maria Cristina Petralia, Katia Mangano, and Lyubka Tancheva
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Inorganic Chemistry ,Organic Chemistry ,General Medicine ,Physical and Theoretical Chemistry ,Molecular Biology ,Spectroscopy ,Catalysis ,Computer Science Applications - Abstract
Pomegranate (Punica granatum L.) is a polyphenol-rich food and medicinal plant containing flavonols, anthocyanins, and tannins. Ellagitannins (ETs) are the most abundant polyphenols in pomegranate. A growing body of research shows that polyphenol-rich pomegranate extracts and their metabolites target multiple types of brain cell and support their redox balance, proliferation and survival, as well as cell signaling. Independent studies have demonstrated that the significant neuroprotective effects of ETs are mediated by their antioxidant and anti-inflammatory effects, their chelating properties, by their ability to activate various signaling pathways, as well as the ability to influence mitochondrial damage, thus regulating autophagy, apoptosis and neurotransmitter signaling. The multitude of in vitro and in vivo studies summarized in the present review suggest that pomegranate polyphenols act on both neuronal and glial cells directly, and also affect blood–brain barrier function, restoring redox balance in the blood and brain and increasing blood flow to the brain.
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- 2023
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29. Effects of New Galantamine Derivatives in a Scopolamine Model of Dementia in Mice
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Polina Petkova-Kirova, Albena Alexandrova, Diamara Uzunova, Miroslava Stefanova, Elina Tsvetanova, Almira Georgieva, Lyubomir T. Vezenkov, L. Tancheva, Reni Kalfin, Maria Lazarova, and D. Tsekova
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Male ,Memory, Long-Term ,Scopolamine ,Pharmacology ,Antioxidants ,Cholinergic Antagonists ,Lipid peroxidation ,chemistry.chemical_compound ,Mice ,Alzheimer Disease ,medicine ,Galantamine ,Dementia ,Animals ,Cholinergic neuron ,Cholinesterase ,chemistry.chemical_classification ,biology ,business.industry ,General Neuroscience ,Glutathione peroxidase ,General Medicine ,medicine.disease ,Acetylcholinesterase ,Psychiatry and Mental health ,Clinical Psychology ,Disease Models, Animal ,Memory, Short-Term ,chemistry ,biology.protein ,Cholinesterase Inhibitors ,Geriatrics and Gerontology ,business ,Acetylcholine ,medicine.drug - Abstract
Alzheimer’s disease (AD), a progressive neurodegenerative disorder characterized by memory loss and cognitive functions decline, is a leading cause for dementia and currently ranked as the sixth foremost cause of death. As of present, treatment of AD is symptomatic without convincing therapeutic benefits and new, effective, therapeutic agents are pursued. Due to massive loss of cholinergic neurons and decreased acetylcholine levels, cholinesterase inhibitors like galantamine, remain the backbone of pharmacological treatment of the disease. In the present study, using behavioral and biochemical methods, four newly synthesized galantamine derivatives, Gal 34, Gal 43, Gal 44, and Gal 46, were evaluated for a beneficial effect in a scopolamine model of dementia in mice. They were designed to have all the advantages of galantamine and additionally to inhibit β-secretase and exert favorable effects on plasma lipids. Behavioral tests included step-through inhibitory avoidance, T-maze, and the hole-board test, whereas biochemical evaluations involved assessment of acetylcholinesterase activity, brain monoamines levels, lipid peroxidation, catalase, glutathione peroxidase, and superoxide dismutase activities along with measurement of total glutathione. Results show that Gal 43, Gal 44, and, in particular, Gal 46 are especially effective in improving both short- and long-term memory and in the case of Gal 46 having a significant effect on exploratory activity as well. Although Gal 34 did not show behavioral effects as convincing as those of the other three galantamine derivatives, it demonstrated persuasive antioxidant and restorative capacities, making all four galantamine derivatives promising AD treatment agents and prompting further research, especially that in many of our studies they performed better than galantamine.
- Published
- 2021
30. Beneficial effect of melatonin on motor and memory disturbances in 6-OHDA-lesioned rats
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Miroslava Stefanova, Maria Lazarova, Reni Kalfin, Atanas G. Atanasov, Diamara Uzunova, L. Tancheva, and Luciano Saso
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0301 basic medicine ,Male ,medicine.medical_specialty ,Parkinson's disease ,Movement ,melatonin ,6-OHDA ,Neuroprotection ,Melatonin ,Antiparkinson Agents ,memory ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Neurochemical ,Dopamine ,Internal medicine ,medicine ,Animals ,Neurochemistry ,Rats, Wistar ,Oxidopamine ,Neurotransmitter Agents ,Parkinson’s disease ,pharmacology ,business.industry ,Brain ,Parkinson Disease ,General Medicine ,medicine.disease ,Rats ,030104 developmental biology ,Endocrinology ,Serotonin ,business ,030217 neurology & neurosurgery ,Acetylcholine ,medicine.drug - Abstract
Previous evidence has shown a link between neurodegenerative diseases, including Parkinson's disease (PD), and melatonin. The data in the literature about the impact of the hormone under different experimental PD conditions are quite controversial, and its effect on memory impairment in the disease is very poorly explored. The current research was aimed at investigating the role of melatonin pretreatment on memory and motor behavior in healthy rats and those with the partial 6-hydroxydopamine (6-OHDA) model of PD. All rodents were pretreated with melatonin (20 mg/kg, intraperitoneally) for 5 days. At 24 h and 7 days after the first treatment for healthy rats, and at the second and third week post-lesion for those with PD, the animals were tested behaviorally (apomorphine-induced rotations, rotarod, and passive avoidance tests). The neurochemical levels of dopamine (DA), acetylcholine (ACh), noradrenaline (NA), and serotonin (Sero) in the brain were also determined. The results showed that in healthy animals, melatonin pretreatment had amnestic and motor-suppressive effects and did not change the levels of measured brain neurotransmitters. In animals with PD, melatonin pretreatment exerted a neuroprotective effect, manifested as a significantly decreased number of apomorphine-induced rotations, reduced number of falls in the rotarod test, and improved memory performance. The brain DA and ACh concentrations in the same animals were restored to the control levels, and those of NA and Sero did not change. Our results demonstrate a beneficial effect of melatonin on memory and motor disturbance in 6-OHDA-lesioned rats.
- Published
- 2021
31. Synthesis, characterization and cytotoxicity evaluation of Ni(II), Cu(II), and Zn(II) complexes with deoxycholate ligand
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Ovidiu Oprea, L. Dyakova, Melita Vidaković, Radostina Alexandrova, Gabriela Marinescu, George Miloshev, Rossen Spasov, Reni Kalfin, Bela Vasileva, Tanya Zhivkova, Milena Georgieva, and Daniela C. Culita
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colorectal cancer cells ,Transition metal ,Ligand ,Chemistry ,deoxycholate complexes ,cytotoxicity ,General Pharmacology, Toxicology and Pharmaceutics ,Cytotoxicity ,transition metals ,Nuclear chemistry ,Characterization (materials science) - Abstract
Three new complexes of Ni(II), Cu(II) and Zn(II) with deoxycholate anion, of the type M(DCA)2 · nH2O (M = Cu(II) n = 4, M = Ni(II) n = 3 and M = Zn(II) n = 2) have been synthesized and characterized on the basis of elemental analysis, FTIR and UV-Vis spectroscopy, thermal analysis, molar conductivity and magnetic measurements. The cytotoxicity of the synthesized complexes was tested against HT29 human colorectal cancer cells. Applied at a concentration range of 10 - 200 µg/mL, sodium deoxycholate and its metal complexes have been found to decrease viability and growth of cultured HT29 cells in a time- and concentration-dependent manner in short-term and long-term experiments. The ability of the complexes to induce pathological changes, genotoxicity and apoptosis in the treated cells has also been proved. In addition, the complexes demonstrated a cytotoxic effect in HT29-OxPt (resistant to oxaliplatin) cells, allowing to conclude that they are more pronounced cytotoxic agents as compared to the sodium deoxycholate alone.
- Published
- 2021
32. Analysis of angiotensin II-Induced rat urinary bladder contractions in the presence of angiotensin II receptors blockers
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Tsvetelin Georgiev, P. Hadzhibozheva, Reni Kalfin, and A. Tolekova
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Male ,medicine.medical_specialty ,Angiotensin receptor ,Pyridines ,Physiology ,Urinary Bladder ,030209 endocrinology & metabolism ,Losartan ,Angiotensin Receptor Antagonists ,03 medical and health sciences ,0302 clinical medicine ,Physiology (medical) ,Internal medicine ,Animals ,Homeostasis ,Medicine ,Rats, Wistar ,Receptor ,Urinary bladder ,business.industry ,Angiotensin II ,Imidazoles ,General Medicine ,Smooth muscle contraction ,Rat Urinary Bladder ,Rats ,Endocrinology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,cardiovascular system ,Stress, Mechanical ,business ,Angiotensin II Type 1 Receptor Blockers ,hormones, hormone substitutes, and hormone antagonists ,circulatory and respiratory physiology - Abstract
An application of a specific analysis on recordings obtained from urinary bladder (UB) preparations influenced with Angiotensin II (AngII) and AngII receptor (ATR) blockers was performed.UB preparations were divided as follows: group 1 stimulated with AngII only; group 2:PD123319 (ATR type-2 blocker)+AngII; group 3:Losartan (ATR type-1 blocker)+AngII. The averaged time and force parameters of the contractions were processed by a spline interpolation and graphic images of the different patterns of the contractile activity were obtained.The speed of AngII-induced UB contraction, when PD123319 was administered, was significantly higher than those, registered by the application of AngII alone and Losartan + AngII. The presence of Losartan markedly delayed the speed of the overall AngII-induced contraction.The study indicates the contribution of both ATR subtypes for the development of AngII-induced UB contraction. Our results showed that probably ATR mediate a reciprocal dynamic response to AngII in the bladder.
- Published
- 2019
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33. Comparative cytotoxicity assays performed using a free porphyrin and its Zn(II), Co(II) and Cu() Complexes. Influence of optical and aggregation properties
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Eugenia Fagadar-Cosma, Radostina Alexandrova, Reni Kalfin, and Ramona Tudose
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chemistry.chemical_compound ,Chemistry ,General Chemistry ,Cytotoxicity ,Porphyrin ,Nuclear chemistry - Published
- 2018
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34. Cultural Isolation and Characteristics of the Blood Microbiome of Healthy Individuals
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Reni Kalfin, Michele Equestre, Stefan Panaiotov, Elena Nikolova, and Georgi Filevski
- Subjects
0301 basic medicine ,Blood type ,Operational taxonomic unit ,Phylum ,02 engineering and technology ,General Medicine ,Biology ,021001 nanoscience & nanotechnology ,16S ribosomal RNA ,Isolation (microbiology) ,DNA sequencing ,law.invention ,Microbiology ,03 medical and health sciences ,030104 developmental biology ,Gram staining ,law ,Microbiome ,0210 nano-technology - Abstract
Background: On the analogy of the non-pathogenic microbiota found in oral cavity, skin and gastrointestinal tract, existence of blood microbiota was confirmed by DNA sequencing, but never deeply characterized. Hypothesis for the existence of dormant blood microbiota in healthy humans have been arisen and single species have been isolated. The aim of our study was to resuscitate and investigate the biodiversity of bacterial and fungal dormant blood microbiota in healthy individuals by blood culturing and NGS DNA sequencing. Results: Twenty eight blood samples of healthy individuals, seven for each blood type, were studied. Several culture media were tested. Blood microbiota resuscitation was performed in BHI broth supplemented with vitamin K 1 mg/ml, 2% sucrose, 0.25% sodium citrate and 0.2% yeastolate at 43?C for 72 h. All tested blood samples were culture positive, as confirmed by Gram staining and TEM. TEM images demonstrated well defined cell structures. Analysis for bacterial and eukaryotic species was performed by 16S rRNA and ITS2 targeted sequencing. The obtained sequences were clustered (≥97% identity) in Operational Taxonomic Units (OTUs). Among cultured and uncultured samples we identified OTUs similarity with 47 bacterial orders belonging to 15 phyla and 39 fungi orders blonging to 2 phyla. For the first time we demonstrated isolation and sequencing identification of fungal blood microbiota in healthy individuals. Blood-group differences were identified among the bacterial microbiome compositions. Conclusion: The dormant blood microbiome is innate of the healthy individuals. Interventional strategies to bind the host blood microbiome with the states of health and disease remain an unmet research goal.
- Published
- 2018
- Full Text
- View/download PDF
35. Neurochemical evidence that cocaine- and amphetamine-regulated transcript (CART) 55–102 peptide modulates the dopaminergic reward system by decreasing the dopamine release in the mouse nucleus accumbens
- Author
-
Angelina Rakovska, Katalin Windisch, Polina Petkova-Kirova, Reni Kalfin, Hristo Gagov, and Mária Baranyi
- Subjects
Male ,0301 basic medicine ,medicine.medical_specialty ,Dopamine ,Nerve Tissue Proteins ,Striatum ,Nucleus accumbens ,Nucleus Accumbens ,Cocaine and amphetamine regulated transcript ,Tissue Culture Techniques ,Ventral pallidum ,Mice ,Norepinephrine ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Cocaine ,Dopamine Uptake Inhibitors ,Reward ,Internal medicine ,medicine ,Animals ,Humans ,Neurotransmitter ,Chemistry ,General Neuroscience ,Homovanillic acid ,Dopaminergic ,Homovanillic Acid ,Phenylethyl Alcohol ,Electric Stimulation ,Peptide Fragments ,030104 developmental biology ,Endocrinology ,nervous system ,3,4-Dihydroxyphenylacetic Acid ,Extracellular Space ,030217 neurology & neurosurgery ,medicine.drug - Abstract
CART (Cocaine- and Amphetamine-Regulated Transcript) peptide is a neurotransmitter naturally occurring in the CNS and found mostly in nucleus accumbens, ventrotegmental area, ventral pallidum, amygdalae and striatum, brain regions associated with drug addiction. In the nucleus accumbens, known for its significant role in motivation, pleasure, reward and reinforcement learning, CART peptide inhibits cocaine and amphetamine-induced dopamine-mediated increases in locomotor activity and behavior, suggesting a CART peptide interaction with the dopaminergic system. Thus in the present study, we examined the effect of CART (55-102) peptide on the basal, electrical field stimulation-evoked (EFS-evoked) (30V, 2Hz, 120 shocks) and returning basal dopamine (DA) release and on the release of the DA metabolites 3,4-dihydroxyphenyl acetaldehyde (DOPAL), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 3,4-dihydroxyphenylethanol (DOPET), 3-methoxytyramine (3-MT) as well as on norepinephrine (NE) and dopamine-o-quinone (Daq) in isolated mouse nucleus accumbens, in a preparation, in which any CART peptide effects on the dendrites or soma of ventral tegmental projection neurons have been excluded. We further extended our study to assess the effect of CART (55-102) peptide on basal cocaine-induced release of dopamine and its metabolites DOPAL, DOPAC, HVA, DOPET and 3-MT as well as on NE and Daq. To analyze the amount of [3H]dopamine, dopamine metabolites, Daq and NE in the nucleus accumbens superfusate, a high-pressure liquid chromatography (HPLC), coupled with electrochemical, UV and radiochemical detections was used. CART (55-102) peptide, 0.1μM, added alone, exerted: (i) a significant decrease in the basal and EFS-evoked levels of extracellular dopamine (ii) a significant increase in the EFS-evoked and returning basal levels of the dopamine metabolites DOPAC and HVA, major products of dopamine degradation and (iii) a significant decrease in the returning basal levels of DOPET. At the same concentration, 0.1μM, CART (55-102) peptide did not have any effect on the release of noradrenaline. In the presence of CART (55-102) peptide, 0.1μM, the effect of cocaine, 30μM, on the basal dopamine release was inhibited and the effect on the basal DOPAC release substantially increased. To our knowledge, our findings are the first to show direct neurochemical evidence that CART (55-102) peptide plays a neuromodulatory role on the dopaminergic reward system by decreasing dopamine in the mouse nucleus accumbens and by attenuating cocaine-induced effects on dopamine release.
- Published
- 2017
- Full Text
- View/download PDF
36. Neuroprotective Mechanisms of Three Natural Antioxidants on a Rat Model of Parkinson’s Disease: A Comparative Study
- Author
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Elina Tzvetanova, Ferdinando Nicoletti, Reni Kalfin, Atanas G. Atanasov, Stela Dragomanova, L. Tancheva, Yordan Hodzhev, Simona Miteva, Maria Lazarova, Emanuela Mazzon, Albena Alexandrova, and Nikolay T. Tzvetkov
- Subjects
0301 basic medicine ,Parkinson's disease ,parkinson’s disease ,Physiology ,Clinical Biochemistry ,Rat model ,antioxidant activity ,Pharmacology ,medicine.disease_cause ,Biochemistry ,Neuroprotection ,Article ,Lesion ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Dopamine ,ellagic acid ,medicine ,rat ,Molecular Biology ,α-lipoic acid ,biology ,Chemistry ,lcsh:RM1-950 ,Cell Biology ,medicine.disease ,030104 developmental biology ,lcsh:Therapeutics. Pharmacology ,Catalase ,myrtenal ,biology.protein ,neuroprotection ,medicine.symptom ,dopamine ,030217 neurology & neurosurgery ,Oxidative stress ,medicine.drug ,Ellagic acid - Abstract
We compared the neuroprotective action of three natural bio-antioxidants (AOs): ellagic acid (EA), &alpha, lipoic acid (LA), and myrtenal (Myrt) in an experimental model of Parkinson&rsquo, s disease (PD) that was induced in male Wistar rats through an intrastriatal injection of 6-hydroxydopamine (6-OHDA). The animals were divided into five groups: the sham-operated (SO) control group, striatal 6-OHDA-lesioned control group, and three groups of 6-OHDA-lesioned rats pre-treated for five days with EA, LA, and Myrt (50 mg/kg, intraperitoneally- i.p.), respectively. On the 2nd and the 3rd week post lesion, the animals were subjected to several behavioral tests: apomorphine-induced rotation, rotarod, and the passive avoidance test. Biochemical evaluation included assessment of main oxidative stress parameters as well as dopamine (DA) levels in brain homogenates. The results showed that all three test compounds improved learning and memory performance as well as neuromuscular coordination. Biochemical assays showed that all three compounds substantially decreased lipid peroxidation (LPO) levels, and restored catalase (CAT) activity and DA levels that were impaired by the challenge with 6-OHDA. Based on these results, we can conclude that the studied AOs demonstrate properties that are consistent with significant antiparkinsonian effects. The most powerful neuroprotective effect was observed with Myrt, and this work represents the first demonstration of its anti-Parkinsonian impact.
- Published
- 2020
37. Emerging neurological and psychobiological aspects of COVID-19 infection
- Author
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Stela Dragomanova, Maria Cristina Petralia, L. Tancheva, A. Solak, Ferdinando Nicoletti, Simona Miteva, Maria Lazarova, Dobri Yarkov, Eugenio Cavalli, Reni Kalfin, Alessia Bramanti, and Rosella Ciurleo
- Subjects
medicine.medical_specialty ,Parkinson's disease ,Coronavirus disease 2019 (COVID-19) ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Central nervous system ,Review ,Asymptomatic ,lcsh:RC321-571 ,03 medical and health sciences ,0302 clinical medicine ,Neuro-COVID ,Pandemic ,medicine ,COVID-19 ,Cytokines ,Parkinson’s disease ,Peripheral nervous system ,SARS-CoV-2 ,Intensive care medicine ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,030304 developmental biology ,0303 health sciences ,business.industry ,General Neuroscience ,medicine.disease ,Pathophysiology ,medicine.anatomical_structure ,medicine.symptom ,business ,030217 neurology & neurosurgery - Abstract
The SARS-CoV-2 virus, first reported in December 2019 in China, is the causative agent of the current COVID-19 pandemic that, at the time of writing (1 November 2020) has infected almost 43 million people and caused the death of more than 1 million people. The spectrum of clinical manifestations observed during COVID-19 infection varies from asymptomatic to critical life-threatening clinical conditions. Emerging evidence shows that COVID-19 affects far more organs than just the respiratory system, including the heart, kidneys, blood vessels, liver, as well as the central nervous system (CNS) and the peripheral nervous system (PNS). It is also becoming clear that the neurological and psychological disturbances that occur during the acute phase of the infection may persist well beyond the recovery. The aim of this review is to propel further this emerging and relevant field of research related to the pathophysiology of neurological manifestation of COVID-19 infection (Neuro-COVID). We will summarize the PNS and CNS symptoms experienced by people with COVID-19 both during infection and in the recovery phase. Diagnostic and pharmacological findings in this field of study are strongly warranted to address the neurological and psychological symptoms of COVID-19.
- Published
- 2020
38. In silico and in vivo analysis of IL37 in multiple sclerosis reveals its probable homeostatic role on the clinical activity, disability, and treatment with fingolimod
- Author
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Manuela Pennisi, Emanuela Mazzon, Maria Sofia Basile, Jovana Ivanovic, Reni Kalfin, Jelena Drulovic, Ferdinando Nicoletti, Sarlota Mesaros, Paolo Fagone, Santa Mammana, Marko Andabaka, Eugenio Cavalli, Maria Cristina Petralia, Vanja Martinovic, and Tatjana Pekmezovic
- Subjects
Adult ,CD4-Positive T-Lymphocytes ,Male ,In silico ,Pharmaceutical Science ,Pharmacology ,Peripheral blood mononuclear cell ,Cytokines ,Fingolimod ,Interleukin 37 ,Multiple sclerosis ,Article ,Analytical Chemistry ,03 medical and health sciences ,0302 clinical medicine ,Recurrence ,In vivo ,Drug Discovery ,Diseases in Twins ,Humans ,Medicine ,Potency ,Computer Simulation ,Physical and Theoretical Chemistry ,030304 developmental biology ,0303 health sciences ,Cluster of differentiation ,Fingolimod Hydrochloride ,business.industry ,Organic Chemistry ,Interleukin ,Twins, Monozygotic ,Middle Aged ,medicine.disease ,Up-Regulation ,Gene Expression Regulation ,Chemistry (miscellaneous) ,Case-Control Studies ,Disease Progression ,Molecular Medicine ,Female ,business ,030217 neurology & neurosurgery ,Interleukin-1 ,medicine.drug - Abstract
We evaluated the in silico expression and circulating levels of interleukin (IL)37 in patients with different forms of multiple sclerosis (MS) and also upon treatment with different disease-modifying drugs. The combined interpretation of the resulting data strengthens and extends the current emerging concept that endogenous IL37 plays an important role in determining onset and progression of MS. The in silico analysis revealed that production of IL37 from cluster of differentiation (CD)4+ T cells from MS patients was reduced in vitro as compared to healthy controls. The analysis of the datasets also demonstrated that &ldquo, higher&rdquo, levels of IL37 production from PBMC entailed significant protection from MS relapses. In addition, the in vivo part of the study showed that IL37 was selectively augmented in the sera of MS patients during a relapse and that treatment with the high potency disease-modifying drug fingolimod significantly increased the frequency of patients with circulating blood levels of IL37 (6/9, 66%) as compared to patients receiving no treatment (n = 48) or platform therapy (n = 59) who had levels of IL37 below the limit of the sensitivity of the assay. This finding therefore anticipates that fingolimod may at least partially exert its beneficial effects in MS by upregulating the production of IL37.
- Published
- 2020
39. Disulfiram as a New Potential Anticancer Agent – Influence on Viability and Proliferation of Virus-transformed Tumour Cells
- Author
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Reni Kalfin, Radostina Alexandrova, Tanya Zhivkova, Rossen Spasov, and L. Dyakova
- Subjects
Chemistry ,Disulfiram ,medicine ,Cancer research ,Virus ,medicine.drug - Published
- 2019
- Full Text
- View/download PDF
40. Neurochemical evidence that cysteamine modulates amphetamine-induced dopaminergic neuronal activity in striatum by decreasing dopamine release: an in vivo microdialysis study in freely moving rats
- Author
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Angelina Rakovska, Daniel C. Javitt, Reni Kalfin, Rosalind Ang, Andrea Balla, and Polina Petkova-Kirova
- Subjects
0301 basic medicine ,Male ,Microdialysis ,medicine.medical_treatment ,Cysteamine ,Dopamine ,Striatum ,Pharmacology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Neurochemical ,medicine ,Animals ,Rats, Wistar ,Amphetamine ,Chemistry ,General Neuroscience ,Dopaminergic Neurons ,Dopaminergic ,Corpus Striatum ,Rats ,Stimulant ,030104 developmental biology ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Elevated striatal dopamine release is thought to be one of the hallmarks of schizophrenia and correlates with its positive symptoms. Cysteamine (2-aminoethane-1-thiol), a compound naturally found in mammalian cells, inhibits amphetamine-induced dopamine-mediated increases in locomotor activity and behavior and blocks amphetamine-induced deficits in sensorimotor gating, suggesting cysteamine interaction with the dopaminergic system. Therefore, in the present study, we examined, in vivo, in the striatum of awake, freely moving rats the effect of cysteamine on the basal and amphetamine-induced release of dopamine, given also the fact that amphetamine-induced psychosis is a widely accepted animal model of schizophrenia. In vivo transversal microdialysis was used to collect the striatal dialysate samples and high performance liquid chromatography (HPLC), coupled with electrochemical detection- to assess the samples dopamine levels. Amphetamine,1μM, administered locally through the microdialysis fiber, running through both the left and right striatum, produced a significant increase in the extracellular level of dopamine. The increase lasted over an hour when dopamine gradually returned to its basal levels. Cysteamine hydrochloride, perfused locally in the sriatum via the microdialysis probe, at a concentration of 100 μM did not change the basal release of dopamine. However, at the same concentration and administered together with amphetamine, 1μM, it completely inhibited the stimulant effect of amphetamine. To our knowledge, our in vivo results are the first to show direct neurochemical evidence that cysteamine is able to modulate amphetamine-induced dopamine neuronal activity in the striatum of awake, freely moving rats by suppressing the increased by amphetamine release of dopamine.
- Published
- 2019
41. Preventive Effect of Two New Neurotensin Analogues on Parkinson's Disease Rat Model
- Author
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Reni Kalfin, Radoslav Klissurov, Svetlana Stoeva, Tamara Pajpanova, Maria Lazarova, Andrey Popatanasov, and L. Tancheva
- Subjects
0301 basic medicine ,Male ,medicine.medical_specialty ,Parkinson's disease ,Neurology ,Neuropeptide ,Neuroprotection ,Lesion ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,0302 clinical medicine ,Dopamine ,Internal medicine ,medicine ,Animals ,Neurochemistry ,Rats, Wistar ,Oxidopamine ,Neurotensin ,business.industry ,Parkinson Disease ,General Medicine ,medicine.disease ,Peptide Fragments ,Rats ,030104 developmental biology ,Endocrinology ,Neuroprotective Agents ,chemistry ,Blood-Brain Barrier ,medicine.symptom ,business ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Close functional and anatomical interactions between the neurotensin (NT) and dopamine (DA) systems suggest that NT could be associated with Parkinson’s Disease (PD). However, clinical use of NT is limited due to its rapid degradation. This has led to the synthesis of a number of new NT fragment 8-13 [NT(8-13)] analogues, such as NT2 and NT4, to avoid the fast biodegradation of NT. The aim of this study was to investigate the neuroprotective effects of NT2 and NT4 on an experimental model of Parkinson’s disease in rats induced with 6-hydroxydopamine (6-OHDA) treatment, producing striatal lesions. Wistar male rats were divided into different groups: a sham-operated (SO) group, a striatal 6-OHDA-lesioned control group, two groups of 6-OHDA-lesioned rats treated for 5 days with NT2 or NT4 (10 mg/kg, intraperitoneally) and a NT-treated group as reference. During the first and second week post lesion the animals were subjected to a number of behavioral tests (apomorphine-induced rotations, rotarod, passive avoidance test), and brain tissue was evaluated histologically and also assessed for DA levels. The results showed that both the number of apomorphine-induced rotations and falls (rotarod test) increased in the 6-OHDA group relative to the SO group. At the same time, the 6-OHDA-treated group showed significant memory impairment, based on the to step-through test, compared to the SO group. Treatment with NT2 and NT4 significantly decreased the number of apomorphine-induced rotations and improved the memory of lesioned animals, with these NT analogues demonstrating better neuroprotective and neuromodulatory effects than NT. DA content in the brain of the PD rats treated with NT2 and NT4 increased, possibly due to attenuation of the loss of DA-ergic neurons. NT2 and NT4 were found to easily penetrate the blood–brain barrier and they showed a better stability than the reference NT neuropeptide. In conclusion, the NT approach represents an attractive strategy for the treatment of neurodegenerative disease.
- Published
- 2018
42. 3d metal complexes with meloxicam as therapeutic agents in the fight against human glioblastoma multiforme and cervical carcinoma
- Author
-
D.-C. Culita, Tanya Zhivkova, Gabriela Marinescu, Marin Alexandrov, L. Dyakova, Radostina Alexandrova, Milena Georgieva, Luminita Patron, George Miloshev, and Reni Kalfin
- Subjects
Gel electrophoresis ,Neutral red ,biology ,Chemistry ,Acridine orange ,Pharmacology ,biology.organism_classification ,Molecular biology ,Staining ,Comet assay ,HeLa ,chemistry.chemical_compound ,Propidium iodide ,Cytotoxicity ,Biotechnology - Abstract
The aim of our study was to evaluate the influence of selective non-steroidal anti-inflammatory drug meloxicam and its metal (Cu(II), Zn(II), Co(II), Ni(II)) complexes on the viability and proliferation of cultured humancarcinoma of the uterine cervix (HeLa) and glioblastoma multiforme (8MGBA) cells. The investigations were performed by short-term (24 h–96 h, with monolayer cultures) and long-term (16 d, with three-dimensional colonies of cancer cells) experiments by using methods with different molecular/cellular targets and mechanisms of action, such as thiazolyl blue tetrazolium bromide (MTT) test, neutral red uptake cytotoxicity assay, crystal violet staining, double staining with acridine orange and propidium iodide, alkaline version of single cell gel electrophoresis (comet assay) and colony-forming technique. The obtained results revealed that the application of the examined compounds at concentrations ranging from 5 µg/mL to 500 µg/mL induced cytopathological changes, including DNA damages in the ...
- Published
- 2015
- Full Text
- View/download PDF
43. Dormant fungi in the blood microbiome of healthy individuals
- Author
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Reni Kalfin, Georgi Filevski, Michele Equestre, Elena Nikolova, and Stefan Panaiotov
- Published
- 2017
- Full Text
- View/download PDF
44. Short-term administration of melatonin or ghrelin on diabetic rats: effects on angiotensin II and vasopressin-induced uterine contractility
- Author
-
A. Tolekova, T. Georgiev, P. Hadzhibozheva, and Reni Kalfin
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Vasopressin ,Physiology ,Vasopressins ,Uterus ,Drug Administration Schedule ,Diabetes Mellitus, Experimental ,Contractility ,Melatonin ,03 medical and health sciences ,Uterine Contraction ,0302 clinical medicine ,Internal medicine ,medicine ,Animals ,Rats, Wistar ,Estrous cycle ,business.industry ,Angiotensin II ,Uterine horns ,General Medicine ,Ghrelin ,Rats ,030104 developmental biology ,Endocrinology ,medicine.anatomical_structure ,Treatment Outcome ,Female ,business ,hormones, hormone substitutes, and hormone antagonists ,030217 neurology & neurosurgery ,medicine.drug - Abstract
The aim of the present study was to investigate the effects of Angiotensin II (Ang II) and Arginin-Vasopressin (AVP) on contractility of non-pregnant uterus in diabetic Wistar rats and to explore whether one-week administration of Melatonin (MLT) or Ghrelin (GHR) will change the response of diabetic uterine muscle to AngII and AVP. Uterine horns, prepared by the method of isolated tissues were investigated as well as glycemic profile, blood pressure and body weight. The research of smooth muscle contractions was made by a new method of analysis, characterizing in detail the various phases of the myometrial activity. Differences in the development of the peptide-mediated smooth muscle contractions depending on the phase of the estrous cycle were observed. Experimental diabetes had a pronounced negative effect on force and time-parameters of AngII and AVP-stimulated uterine contractions. Administration of GHR or MLT had a beneficial effect on the glycemic status of diabetic rats and partially improved the response of uterine preparations to the peptides. The application of MLT increased both force and time-parameters of Ang II-and AVP-stimulated uterine contractions while treatment with GHR increased power characteristics and shortened contraction and relaxation of the smooth muscle process.
- Published
- 2016
45. Modulation of acetylcholine release by cholecystokinin in striatum – receptor specificity; role of dopaminergic neuronal activity
- Author
-
Reni Kalfin, Polina Petkova-Kirova, Maria Grazia Giovannini, and Angelina Rakovska
- Subjects
Male ,medicine.medical_specialty ,Dopamine ,Nigrostriatal pathway ,Striatum ,digestive system ,Cholecystokinin receptor ,Sincalide ,chemistry.chemical_compound ,Organ Culture Techniques ,Internal medicine ,medicine ,Animals ,Rats, Wistar ,Neurotransmitter ,Cholecystokinin ,Dopaminergic Neurons ,General Neuroscience ,digestive, oral, and skin physiology ,Dopaminergic ,Acetylcholine ,Corpus Striatum ,Receptor, Cholecystokinin B ,Rats ,Receptor, Cholecystokinin A ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Cholinergic ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug - Abstract
Cholecystokinin, a neuroactive peptide functioning as a neurotransmitter and neuromodulator in the central nervous system, mediates a number of processes and is implicated in neurological and psychiatric disorders such as Parkinson's disease, anxiety and schizophrenia. Striatum is one of the brain structures with the highest concentrations of CCK in the brain, rich in CCK receptors as well. The physiological effect of CCK on cholinergic interneurons, which are the major interneurons in striatum and the modulatory interactions which exist between dopamine, acetylcholine and cholecystokinin in this brain structure are still unclear. We studied the effect of cholecystokinin octapeptide (CCK-8) on the release of acetylcholine (ACh) from striatal slices of the rat brain. CCK-8 (0.01-0.1μM) showed no statistically significant effect on the basal but enhanced dose-dependently the electrically (2Hz)-evoked release of [(3)H]ACh. When slices were preperfused with 100μM sulpiride, a selective dopamine D(2) receptor antagonist, the CCK-8 (0.01μM) effect on electrically stimulated ACh release was increased nearly 2-fold. A similar increase was observed after depletion of endogenous dopamine (DA) from nigro-striatal dopaminergic neurons with 6-hydroxydopamine (6-OHDA) (2× 250μg/animal, i.c.v.). Furthermore in the presence of dopamine (100μM) or apomorphine (10μM), the prototypical DA receptor agonist, CCK-8 (0.01μM) failed to enhance the stimulation-evoked release of [(3)H]ACh. The D(2) receptor agonist quinpirol (1μM) abolished the CCK-8 effect on electrically stimulated ACh release as well. The increase in electrically induced [(3)H]ACh release produced by 0.01μM CCK-8 was antagonized by d,l loxiglumide (CR 1505), 10μM, a non-peptide CCK-A receptor antagonist and by Suc-Tyr-(OSO3)-Met-Gly-Trp-Met-Asp-β-phenethyl-amide (GE-410), 1μM, a peptide CCK-A receptor antagonist. The antagonistic effect of GE-410 on the CCK-8-potentiated, electrically induced release of [(3)H]ACh was studied in striatum for the first time. CAM 1028 (10μM), a CCK-B receptor antagonist, also prevented the potentiating effect of CCK-8 (0.01μM) on electrically stimulated release of [(3)H]ACh. The presented results indicate that (i) CCK-8 is capable of increasing ACh elicited by field electrical stimulation in striatum; (ii) CCK-8 is more effective in its ACh-stimulating effect when dopaminergic activity in striatum is blocked i.e. CCK-8-facilitated release of electrically induced ACh from cholinergic interneurons in the striatum is under the inhibitory control of the tonic activity of dopamine from the nigrostriatal pathway; (iii) the enhancing effect of CCK-8 on electrically evoked ACh release is mediated through both CCK-A and CCK-B cholecystokinin receptors located most likely on the cell bodies of cholinergic interneurons in striatum.
- Published
- 2012
- Full Text
- View/download PDF
46. Directed synthesis, toxicity and neuropharmacological activity of new amantаdine derivatives
- Author
-
Radoslav Chayrov, L. Tancheva, Reni Kalfin, Ivanka Stankova, Andrey Popatanasov, and Maria Lazarova
- Subjects
Chemistry ,Toxicity ,02 engineering and technology ,General Medicine ,Pharmacology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,0210 nano-technology ,Toxicology ,01 natural sciences ,0104 chemical sciences - Published
- 2017
- Full Text
- View/download PDF
47. ZN(II)/AU(I) AND ZN(II)/AG(I) COMPLEXES WITH SALEN SCHIFF BASE EXPRESS PROMISING CYTOTOXIC ACTIVITY IN HUMAN CANCER CELLS
- Author
-
Luminita Patron, Radostina Alexandrova, L. Dyakova, Gabriela Marinescu, Pavel Mitrenga, Tanya Zhivkova, Reni Kalfin, Daniela C. Culita, and Rossen Spasov
- Subjects
Pharmacology ,Neutral red ,Acridine orange ,Pharmaceutical Science ,medicine.disease ,Molecular biology ,Staining ,chemistry.chemical_compound ,chemistry ,Cancer cell ,Carcinoma ,medicine ,Cytotoxic T cell ,Pharmacology (medical) ,Propidium iodide ,Cytotoxicity - Abstract
Objective: The aim of our study was to evaluate the influence of two complexes of Zn(II)/Au(I) and Zn(II)/Ag(I) with Schiff base ligand (H2Salen) obtained from the condensation reaction between salicylaldehyde and ethylenediamine (abbreviated ZnSalenAu, ZnSalenAg) on viability and proliferation of cultured human cancer cells.Methods: The following cell lines were used as model systems: Human cervical carcinoma (cervical carcinoma), A549 (non-small cell lung cancer [NSCLC]), glioblastoma multiforme (8MGBA), and A431 (squamous cell carcinoma) and its multidrug-resistant (MDR) clones A431-MDR, A431-MRP, and A431-ABCG2 that express mdr1, mrp1, or abcg2 gene, respectively. The investigations were performed by thiazolyl blue tetrazolium bromide test, neutral red uptake cytotoxicity assay, crystal violet staining, hematoxylin and eosin staining, double staining with acridine orange, and propidium iodide in short-term experiments (12–72 h, with monolayer cell cultures) as well as colony-forming method in long-term experiments (25 days, with three dimensional cancer cell colonies).Results: The results obtained revealed that ZnSalenAu and ZnSalenAg decreased significantly viability and proliferation of the treated cells in a time- and concentration-dependent manner being more active as compared to the free ligand H2Salen.Conclusion: The present study demonstrates for the 1st time the ability of two heterometallic complexes ZnSalenAu and ZnSalenAg to decrease significantly viability and proliferation of cultured cell lines established from some of the most common and aggressive human cancers (NSCLC, carcinoma of uterine cancer, 8MGBA, and squamous cell carcinoma) as well as MDR cancer cells.
- Published
- 2019
- Full Text
- View/download PDF
48. Ni (II) complexes with different ligands express various degree of cytotoxicity
- Author
-
Radostina Alexandrova, Luminita Patron, G. Miloshev, Gabriela Marinescu, Tanya Zhivkova, L. Dyakova, O. Costisor, D.-C. Culita, Milena Georgieva, R. Tudose, Reni Kalfin, E. M. Mosoarca, and Ivayla Pantcheva
- Subjects
Chemistry ,Stereochemistry ,General Medicine ,Toxicology ,Cytotoxicity ,Degree (temperature) - Published
- 2018
- Full Text
- View/download PDF
49. Crystal Structure and Cytotoxic Activity of Co(II) Complex Containing N,N-Tetra-(4-Antipyrylmethyl)-1,2-Diaminoethane (TAMEN) as Ligand
- Author
-
Radostina Alexandrova, Ramona Tudose, Ingo Pantenburg, Elena Maria Mosoarca, Gerd Meyer, Otilia Costisor, Wolfgang Linert, and Reni Kalfin
- Subjects
Cell Survival ,Stereochemistry ,chemistry.chemical_element ,Antineoplastic Agents ,Mannich base ,Crystallography, X-Ray ,Ligands ,Cell Line ,chemistry.chemical_compound ,Coordination Complexes ,Drug Discovery ,Animals ,Humans ,Cytotoxic T cell ,Dimethyl Sulfoxide ,Cell Proliferation ,Molecular Structure ,Ligand ,Cell growth ,Dimethyl sulfoxide ,Cobalt ,Hep G2 Cells ,Hep G2 ,chemistry ,Cell culture ,Cattle - Abstract
The mononuclear complex, [Co(TAMEN)](ClO(4))(2) (DMSO), containing the Mannich base N,N'-tetra-(4-antipyrylmethyl)-1,2-diaminoethane (TAMEN) as ligand, was synthesized and characterised by conductometric, electronic and infrared spectroscopic properties. The single-crystal X-ray structure show the presence of two well defined units, [Co(TAMEN)](2+) and (ClO(4))(-). The complex cation contains cobalt(II) in the pseudo octahedral environment created by the N(2)O(4) donor set of TAMEN. The cobalt(II) complex have been screened for its cytotoxic activity against three cultured human cell lines established from hepatoma (Hep G2), breast (MCF-7) and lung (A549) cancers as well as on non-tumor bovine kidney (MDBK) cells. The cytotoxic activity of the ligand TAMEN was assessed on one tumor (Hep G2) and one non-tumor (MDBK) cell lines. The cobalt(II) compound was found to decrease in a time- and concentration- dependent manner the viability of tumor (A549, MCF-7, Hep G2) cell lines, while the ligand TAMEN expressed proliferative activity on hepatoma (HepG2) and bovine kidney (MDBK) cells, especially after prolonged incubation.
- Published
- 2010
- Full Text
- View/download PDF
50. Exogenous VIP limits zymosan-induced generalized inflammation (ZIGI) in mice
- Author
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Nina Ivanovska, Petya Dimitrova, Reni Kalfin, and Maria Lazarova
- Subjects
medicine.medical_specialty ,Chemokine ,Bilirubin ,Immunology ,Vasoactive intestinal peptide ,Neuropeptide ,Spleen ,Inflammation ,Mice ,chemistry.chemical_compound ,Internal medicine ,medicine ,Animals ,Immunology and Allergy ,Mice, Inbred BALB C ,Creatinine ,biology ,Zymosan ,Organ Size ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Macrophages, Peritoneal ,biology.protein ,Cytokines ,Inflammation Mediators ,medicine.symptom ,hormones, hormone substitutes, and hormone antagonists ,Vasoactive Intestinal Peptide - Abstract
Vasoactive intestinal peptide (VIP) was administered in a model of zymosan-induced generalized inflammation (ZIGI). Its beneficial action was associated with reduced TNF-α and increased IL-10 production, lowered levels of creatinine, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and bilirubin in circulation. VIP diminished the level of RANTES and MIP-1α in peritoneal exudate and circulation. The neuropeptide inhibited NO release from stimulated peritoneal macrophages. Decreased spleen, liver and kidney enlargement and less pathological changes in liver were observed. The effect of VIP was attenuated by pretreatment with VIP antagonist (anti-VIP) before the induction of shock.
- Published
- 2007
- Full Text
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