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The relationship between peroxisome proliferator-activated receptor gamma (PPARγ) expression level and epigenetic modifications occurring in glioblastoma multiforme (GBM) pathogenesis is largely unknown. Herein, we examine the association of PPARγ expression with its promoter and genomic global DNA methylation status, as well as DNA methyltransferases (DNMTs) gene expression in GBM patients.We examined the patterns of promoter methylation and PPARγ expression in 26 GBM tissues and 13 adjacent non-tumor tissues by methylation-specific PCR (MSP), real-time PCR, and ELISA, respectively. Also, we examined the genomic global 5-methyl cytosine levels and DNMTs gene expression using ELISA and real-time PCR methods, respectively.We found that hypermethylation on a specific region of the PPARγ promoter is significantly associated with the downregulation of the PPARγ gene and protein level in GBM patients. Interestingly, the amount of 5-methyl cytosine level was significantly reduced in GBM patients and positively correlated with PPARγ protein expression. Furthermore, the expression level of DNMT1, DNMT3A, and 3B were upregulated in GBM patients and the average expression level of all three DNMTs was positively correlated with tumor area. Also, we found that tumors from cortical regions exhibited a higher global DNA hypomethylation and PPARγ hypermethylation was related to the increase in GBM risk.Our study demonstrated that global DNA methylation and PPARγ epigenetic silencing is associated with the GBM risk. Our data provide a novel molecular mechanistic insight into epigenetic silencing of PPARγ in GBM patients that may be relevant as a key tumor marker for GBM pathogenesis.

Traumatic brain injury (TBI) is a major cause of death and disability. TBI can result in neuropsychiatric and cognitive problems as well as neurodegenerative pathologies that can appear right after or develop and persist years after injury.We conducted a double-blind, randomized, placebo-controlled clinical trial on patients who suffered from TBI three months to three years ago. The patients were randomized to placebo (n = 34) or K-Vie™ group (n = 46) for a treatment period of 3 months. The main primary outcomes include cognitive assessment in the Rey Auditory Verbal Learning Test-Recognition Test (RAVLT), Wechsler adult intelligence Digit Symbol Substitution Test (DSST) and trail-making test part B (TMT-B). Assessments were performed at baseline and at the month 3 follow-up visit. Linear mixed models were carried out to evaluate cognitive changes from baseline across all cognitive assessment tests.The current study showed significant (p 0.05) improvement in cognitive function of patients who were given K-Vie™ compared with placebo across the RAVLT, DSST and TMT-B performance assessments. A larger cohort would be beneficial to further confirm the clinical utility of K-Vie™ and assess its effects in acute phases of TBI.

In the patients with neurological autoimmune diseases such as anti-IgLON5 disease, insomnia symptoms are very common. Clinical diagnosis of the anti-IgLON5 disease is usually made when neurodegenerative processes have occurred. To find the early signs of anti-IgLON5 disease, we evaluate the presence of IgLON5 autoantibodies in the serum of patients with chronic insomnia disease. Based on video-polysomnography, 22 individuals with isolated chronic insomnia disease were found. A control group of 22 healthy people was chosen using the Pittsburgh Sleep Quality Index (PSQI). An indirect immunofluorescence cell-based test of serum anti-IgLON5 antibodies was used to investigate IgLON5 autoimmunity. Anti-IgLON5 antibodies were detected in the serum of four of these patients with the titer of 1/10. The presence of IgLON5 autoantibodies in some patients with chronic insomnia disease can be considered a causing factor of insomnia which can be effective in more specific treatments of these patients. Moreover, the recognition of anti-IgLON5 disease in the early stages and before the progression of tauopathies can be useful in effective and timely treatment.

Recent studies have indicated that dysfunction of gut microbiota, living microorganisms of the digestive tract, plays a role in the pathogenesis of neurodegenerative disorders, indicating the valuable impact of probiotics as a potential preventive or therapeutic strategy.

There is some evidence that cytokines may play an important role in sleep deprivation; however, the underlying mechanisms are still unknown. So, the present study aimed to evaluate the relationship between NOD-like receptor protein 1 (NLRP1) and NOD-like receptor protein 3 (NLRP3) inflammasome activation of blood cells and serum levels of cytokines in individuals with chronic insomnia disorder (CID).Blood samples were collected from 24 individuals with CID and 24 healthy volunteers. The inflammasome activation was evaluated using real-time polymerase chain reaction of NLRP1, NLRP3, apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC) and caspase-1; western blot of NLRP1 and NLRP3; caspase-1 activity assay; and serum levels of interleukin-1β (IL-1β), IL-18 and other cytokines using enzyme-linked immunosorbent assay. Reactive oxygen species generation in blood cells were detected by flow cytometry assay. Also, magnetic resonance imaging scans were obtained on a Siemens Magnetom Avanto 1.5 T MRI whole-body scanner using an eight-channel head coil.Increased activity of NLRP1 and NLRP3 inflammasomes in blood cells, increased serum levels of pro-inflammatory cytokines and decreased serum levels of IL-10 and transforming growth factor β in individuals with CID were found. Significant correlation was observed between increased serum concentration of IL-1β and the severity of insomnia in individuals with CID. The levels of reactive oxygen species in blood cells were found to be correlated with IL-1α and tumor necrosis factor α concentrations in sera from individuals with CID. Moreover, the individuals with CID demonstrated increased right cerebellum cortex and lateral ventricle mean diffusivity bilaterally compared to controls.This study provided new insights on the pathogenesis of CID and the effects of cytokines on inflammasome activation.

The significant role of microRNAs in regulating gene expression and in disease tracking has handed the possibility of robust and accurate diagnosis of various diseases. Measurement of these biomarkers has also had a significant impact on the preparation of natural samples. Discovery of miRNAs is a major challenge due to their small size in the real sample and their short length, which is generally measured by complex and expensive methods . Electrochemical nano-biosensors have made significant progress in this field. Due to the delicate nature of nerve tissue repair and the significance of rapid-fire feature of neurodegenerative conditions, these biosensors can be reliably promising. This review presents advances in the field of neurodegenerative diseases diagnostics. At the same time, there are still numerous openings in this field that are a bright prospect for researchers in the rapid-fire opinion of neurological diseases and indeed nerve tissue repair. This article is protected by copyright. All rights reserved.

In Alzheimer's disease (AD), the most common form of dementia, microtubules (MTs) play a pivotal role through their highly dynamic structure and instability. They mediate axonal transport that is crucial to synaptic viability. MT assembly, dynamic instability and stabilization are modulated by tau proteins, whose detachment initiates MT disintegration. Albeit extensive research, the role of GTPase activity in molecular mechanism of stability remains controversial. We hypothesized that GTPase activity is altered in AD leading to microtubule dynamic dysfunction and ultimately to neuronal death. In this paper, fresh tubulin was purified by chromatography from normal young adult, normal aged, and Alzheimer's brain tissues. Polymerization pattern, assembly kinetics and dynamics, critical concentration, GTPase activity, interaction with tau, intermolecular geometry, and conformational changes were explored via Förster Resonance Energy Transfer (FRET) and various spectroscopy methods. Results showed slower MT assembly process in samples from the brains of people with AD compared with normal young and aged brains. This observation was characterized by prolonged lag phase and increased critical and inactive concentration of tubulin. In addition, the GTPase activity in samples from AD brains was significantly higher than in both normal young and normal aged samples, concurrent with profound conformational changes and contracted intermolecular MT-tau distances as revealed by FRET. These alterations were partially restored in the presence of a microtubule stabilizer, paclitaxel. We proposed that alterations of both tubulin function and GTPase activity may be involved in the molecular neuropathogenesis of AD, thus providing new avenues for therapeutic approaches.

Biological activity of Boswellia extract (BE) has been attributed to its main active ingredients; i.e. Boswellic acids (BAs). BE/BAs possess a promising therapeutic potential in neurodegenerative disorders; including Alzheimer's disease (AD). The multifactorial nature of AD pathophysiology necessitates the development of the disease-modifying agents (DMA). Recent multi-targeting approaches for the DMAs development have brought more attention to the plant-derived compounds regarding their better human compatibility because of their biologic origin. This review addresses the current knowledge on the anti-AD activity of BE/BAs based on the available in silico, in vitro, in vivo studies and clinical trials. The contribution of BE/BAs in inflammatory pathways, Tau and β-amyloid proteins, microtubule functions, oxidative stress, cholinesterase and diabetes/insulin pathways involved in AD have been discussed. BAs efficacy in different AD-related pathways has been confirmed in vitro and in vivo. They can be considered as valuable scaffold/lead compounds for multi-targeted DMAs in anti-AD drug discovery and development.

Excessive exposure to the sources of fluoride in drinking water, oral care products, and food is a widespread problem. Fluoride is associated with impairment in child intelligence development. It causes DNA damage, oxidative stress, and mitochondrial dysfunction, mainly due to the production of reactive oxygen species

COVID-19 is a significant global threat to public health. Despite the availability of vaccines and anti-viral drugs, there is an urgent need for alternative treatments to help prevent and/or manage COVID-19 symptoms and the underlying dysregulated immune response. We hypothesized that administration of InflawellA randomized placebo-controlled double-blind clinical trial was conducted, following definitive confirmation of COVID-19. Forty-seven hospitalized patients with moderate COVID-19 were enrolled and received either the InflawellOur clinical trial revealed an increase in the percentage of oxygen saturation level in patients that received the BAs compared to placebo (P 0.0001). In addition, the average duration of hospitalization was significantly shorter in the BAs group compared with the placebo group (P 0.04). Concomitantly, some improvement in the clinical symptoms including cough, dyspnea, myalgia, headache, and olfactory and gustatory dysfunction were detected in the BAs group. Hematologic findings showed a significant decrease in the percentage of neutrophils (P 0.006) and neutrophil-to-lymphocyte ratio (NLR) levels (P 0.003), associated with a significant increase in the percentage of lymphocytes in the BAs group compared with the placebo (P 0.002). Additionally, a significant decrease in CRP, LDH, IL - 6 and TNF - α levels was detected in the BAs group. Following the intervention, fewer patients in the BAs group were PCR-positive for COVID-19 compared to placebo, though not statistically significant.Overall, the treatment with InflawellThe trial has been registered in https://www.irct.ir with unique identifier: IRCT20170315033086N10 ( https://en.irct.ir/trial/51631 ). IRCT is a primary registry in the WHO registry network ( https://www.who.int/clinical-trials-registry-platform/network/primary-registries ).

The use of neurotrophic factors is considered to be a novel therapeutic approach for restoring and/or maintaining neurological function in neurodegenerative disorders, such as multiple sclerosis (MS). Various studies have shown that conditioned medium produced by oligodendrocyte (OL-CM) contain a variety of neurotrophic factors. Here, we investigated the restorative effects of OL-CM, collected from oligodendrocytes cultured in a self-assembling peptide hydrogels scaffold (PuraMatrix), in experimental autoimmune encephalomyelitis (EAE) mouse model. Neural stem/progenitor cells, isolated from the embryonic mouse brain, were cultured and differentiated into oligodendrocyte. Cell viability and proliferation of oligodendrocytes were assessed by live/dead and MTT assays. Motor functions, myelination, cell infiltration, gliosis, and inflammatory process were assessed in EAE mice after intracranial injection of OL-CM at different concentrations. Application of OL-CM improved clinical score and neurological function in EAE mice and reduced the inflammatory cell infiltration and demyelination. Furthermore, administration of OL-CM reduced the expression of pro-inflammatory cytokines and suppressed the activation of NLRP3-inflammasome complex in EAE mice. These data suggest the potential therapeutic effect of OL-CM for MS treatment.

Introduction: Beta-Boswellic acid (BBA) is a pentacyclic terpene which has been obtained from frankincense and its beneficial effects on neurodegenerative disorders such as Alzheimer’s disease (AD) have been addressed. Methods: In the present study, thermodynamic and kinetic aspects of BBA interaction with Tau protein as one of the important proteins involved in AD in the absence and presence of glucose has been investigated using surface plasmon resonance (SPR) method. Tau protein was immobilized onto the carboxy methyl dextran chip and its binding interactions with BBA were studied at physiological pH at various temperatures. Glucose interference with these interactions was also investigated. Results: Results showed that BBA forms a stable complex with Tau (KD=8.45×10-7 M) at 298 K. Molecular modeling analysis showed a hydrophobic interaction between BBA and HVPGGG segment of R2 and R4 repeated domains of Tau. Conclusion: The binding affinity increased by temperature enhancement, while it decreased significantly in the presence of glucose. Both association and dissociation of the BBA-Tau complex were accompanied with an entropic activation barrier; however, positive enthalpy and entropy changes revealed that hydrophobic bonding is the main force involved in the interaction.

In an attempt to find novel, potent α-glucosidase inhibitors, a library of poly-substituted 3-amino-2,4-diarylbenzo[4,5]imidazo[1,2-a]pyrimidines 3a–ag have been synthesized through heating a mixture of 2-aminobenzimidazoles 1 and α-azidochalcone 2 under the mild conditions. This efficient, facile protocol has been resulted into the desirable compounds with a wide substrate scope in good to excellent yields. Afterwards, their inhibitory activities against yeast α-glucosidase enzyme were investigated. Showing IC50 values ranging from 16.4 ± 0.36 µM to 297.0 ± 1.2 µM confirmed their excellent potency to inhibit α-glucosidase which encouraged us to perform further studies on α-glucosidase enzymes obtained from rat as a mammal source. Among various synthesized 3-amino-2,4-diarylbenzo[4,5]imidazo[1,2-a]pyrimidines, compound 3k exhibited the highest potency against both Saccharomyces cerevisiae α-glucosidase (IC50 = 16.4 ± 0.36 μM) and rat small intestine α-glucosidase (IC50 = 45.0 ± 8.2 μM). Moreover, the role of amine moiety on the observed activity was studied through substituting with chlorine and hydrogen resulted into a considerable deterioration on the inhibitory activity. Kinetic study and molecular docking study have confirmed the in-vitro results.

Thyroid cancer, as the most prevalent endocrine malignancy, comprises nearly 1% of all cancers in the world. The metastatic propagation of thyroid cancer is under the control of a number of modulating processes and factors such as signaling pathways and their components, cell division regulators, metabolic reprogramming factors, extracellular matrix remodelers, epithelial to mesenchymal transition modulators, epigenetic mechanisms, hypoxia and cytokines. Identifying the exact molecular mechanisms of these dysregulated processes could help to discover the key targets for therapeutic purposes and utilizing them as diagnostic, prognostic and predictors of the clinical course of patients. In this review article, we describe different aspects of thyroid cancer metastasis by focusing on defective genes and pathways involved in its metastatic spread.

In this paper, we report fabrication of a simple, stable, low-cost, and easy-to-fabricate substrate for surface enhanced Raman spectroscopy (SERS) applications. Silicon nanowires are one of the widely used nanostructures in different fields of nanotechnology. Through creating and varying the gap between nanowires and reducing their filling ratio and tapering, silicon nanowires are converted to applicable SERS substrates. Furthermore, the effects of annealing and post-KOH etching on these silver-coated silicon nanowire substrates are examined. It is shown that the applied processes remarkably enhance the captured Raman signal. For samples etched with KOH method, an optimized etching time at which the Raman signal reaches its maximum value is obtained as well. Finally, an ultra-high enhancement in the Raman signal is obtained.

The aggregation of Tau into amyloid fibrils is a hallmark of neurodegenerative diseases such as Alzheimer's disease (AD). Compared to the Aβ peptide, tau pathology more closely tracks changes in brain function that are responsible for the onset of early symptoms in AD. Tau belongs to the class of intrinsically disordered protein and folds into an ordered β-structure during aggregation, a process that appears in many cases to be preceded by hyperphosphorylation of Tau monomers. Although Tau fibrils can be formed by heparin-induced aggregation of un-phosphorylated recombinant Tau, it is important to understanding the paradox of Tau's random-like conformations and aggregation propensity. In this study, to look into the effect of charge neutralization on Tau aggregation propensity, solvent accessible lysine residues were chemically acetylated/pseudo-phosphorylated. All Tau variants did not aggregate in the absence of the polyanionic factor; however, in contrast to the wild-type protein, acetylated and pseudo-phosphorylated variants were not able to aggregate even in the presence of the polyanionic cofactor. These aggregation incompetent Tau variants may be good analogs for the phosphorylated Tau, to explore more about the exact role of the phosphorylated Tau monomers in AD progress.

Background: Alzheimer’s disease (AD) is the main cause of the neurodegenerative disorder, which is not detected unless the cognitive deficits are manifested. An early prediagnostic specific biomarker preferably detectable in plasma and hence non-invasive is highly sought-after. Various hypotheses refer to AD, with amyloid-beta (Aβ) being the most studied hypothesis and inflammation being the most recent theory wherein pro-and anti-inflammatory cytokines are the main culprits. Materials and Methods: In this study, the cognitive performance of AD patients (n=39) was assessed using mini-mental state examination (MMSE), AD assessment scale-cognitive subscale (ADAS-cog), and clinical dementia rating (CDR). Their neuropsychiatric symptoms were evaluated through neuropsychiatric inventory–questionnaire (NPI-Q). Moreover, plasma levels of routine biochemical markers, pro-/anti-inflammatory cytokines such as tumor necrosis factor α (TNF-α), interleukin-1 α (IL-1α), IL-1β, IL-2, IL-4, IL-6, IL-8, IL-12p70, IL-10, Interferon-gamma, chemokines, including prostaglandin E2 (PGE-2), monocyte chemoattractant protein-1, interferon gamma-induced protein 10, Aβ peptide species (42, 40) and Transthyretin (TTR) were measured. Results: Our results revealed that Aβ 42/40 ratio and TTR were correlated (r=0.367, P=0.037). IL-1α was directly correlated with ADAS-cog (r=0.386, P=0.017) and Aβ 40 (r=0.379, P=0.019), but was inversely correlated with IL-4 (r=-0.406, P=0.011). Negative correlations were found between MMSE and PGE2 (r=-0.405, P=0.012) and TNF-α/ IL-10 ratio (r=-0.35, P=0.037). CDR was positively correlated with both PGE2 (r=0.358, P=0.027) and TNF-α (r=0.416, P=0.013). There was a positive correlation between NPI-caregiver distress with CDR (r=0.363, P=0.045) and ADAS-cog (r=0.449, P=0.019). Conclusion: Based on the observed correlation between IL-1α, as a clinical moiety, and ADAS-cog, as a clinical manifestation of AD, anti-IL-1α therapy in AD could be suggested. [GMJ.2021;10:e1974]

Experimental autoimmune encephalomyelitis (EAE) as an experimental model of multiple sclerosis (MS) is characterized by demyelination, infiltration of inflammatory cells into the nervous system and dysregulation of serum inflammatory cytokines. We investigated the correlation of serum cytokines and other inflammatory markers with the EAE pathogenesis. After EAE induction, the levels of different serum cytokine/inflammatory mediators were measured. Furthermore, motor functions, myelination, and lymphocyte infiltration in EAE mice were also assessed. Our results revealed that the serum concentrations of T-helper 1 (Th1) and Th17 cytokines, interleukin (IL)-6, IL-1β, IL-1α and prostaglandin E2 in EAE mice were significantly higher than controls. The ratios of pro- to anti-inflammatory cytokines were different between the EAE and the control group. A statistically significant positive correlation was found between the IL-6/IL-10 ratio and the EAE severity, demyelination rate, and lymphocyte infiltration in EAE mice. Results indicate that the profiles of serum pro- and anti-inflammatory cytokines might be useful as biomarkers for monitoring the pathological manifestation of EAE. Furthermore, evaluating the dynamic interplay of serum cytokine levels and the correlation with pathogenic mechanisms of EAE may provide diagnostic and therapeutic insights for MS and some other inflammatory disorders.

Ischaemic stroke represents one of the main causes of disability. According to the broad investigations, it is widely assumed that the contribution of inflammatory mediators is strongly involved in its pathogenesis. Hence, it seems that stroke treatment needs more efficient and inflammatory-targeted compounds to modulate inflammatory-related pathways. Such strategies paved the way to achieve better clinical outcomes along with conventional therapies. Boswellic acids (BAs), the main bioactive compounds of Boswellia sp. resin; are triterpenoids with well-documented anti-inflammatory properties. Compared with NSAIDs, BAs cross blood–brain barrier yet they do not cause serious gastrointestinal adverse effects. Considering BAs anti-inflammatory features, we conducted a randomized double-blind placebo-controlled pilot trial of these compounds as a supplementary therapy. This trial randomized 80 ischaemic stroke patients (40–80-years old) with a 4–20 score according to the National Institutes of Health Stroke Scale (NIHSS), within 72 h of neurological sign onset, in 1-month follow-up period. We assessed NIHSS as primary and plasma levels of TNF-α, IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IFN-γ, IP-10, MCP-1, 8-isoprostane, and PGE2 as secondary outcomes. According to NIHSS evaluation, patients who were allocated to BA group had a significant recovery in neurological function during the 1-month follow-up, compared with the placebo. The levels of plasma inflammatory markers were significantly decreased in BA group after 7 days of intervention in TNF-α, IL-1β, IL-6, IL-8, and PGE2. As a preliminary controlled trial in ischaemic stroke, BAs could improve clinical outcome in the early phases of stroke along with promising changes in plasma inflammatory factors. Clinical trial registrationhttps://www.irct.ir Unique identifier: IRCT20170315033086N5. IRCT is a primary registry in the WHO registry network (https://www.who.int/ictrp/network/primary/en/)

A new series of thiazole-2(3H)-thiones containing 4-(3,4,5-trimethoxyphenyl) moiety were synthesized as diaryl-heterocylic analogs of combretastatin A-4 with anticancer activity. The cytotoxicity evaluation of synthesized compounds against cancer cell lines (A549, MCF-7 and SKOV3) revealed that most of them had potent cytotoxic activity toward all tested cell lines (IC50s

Multiple sclerosis (MS) is known as the most common demyelinating disease worldwide in which previous studies have shown that stress is a risk factor for the disease's onset and progression. Nevertheless, further studies are needed to investigate the consequences of stress in MS pathology. In this study, after 5 days of exposure to psychological and physical stress as a repetitive distress modality, rats were treated with cuprizone. The demyelination degree was compared in animal groups using Luxol fast blue staining, immunohistochemical staining for myelin basic protein and transmission electron microscopy. Outcomes revealed that animals exposed to stress prior to cuprizone ingestion, elicit more intense demyelination. Continuous psychological distress has more severe effects on myelin sheath destruction in the preclinical stage.

In this study, we reported the discovery of pyridazine based 1,2,3-triazole derivatives as inhibitors of α-glucosidase. All target compounds exhibited significant inhibitory activities against yeast and rat α-glucosidase enzymes compared to positive control, acarbose. The most potent compound 6j, ethyl 3-(2-(1-(4-nitrobenzyl)-1H-1,2,3-triazol-4-yl)ethyl)-5,6-diphenylpyridazine-4-carboxylate exhibited IC50 values of 58, and 73 µM. Docking studies indicated the responsibility of hydrophobic and hydrogen bonding interactions in the ligand-enzyme complex stability. The in-vitro safety against the normal cell line was observed by toxicity evaluation of the selected compounds.

Accumulation of human tau protein in the central nervous system is an outstanding feature of Alzheimer's Diseases and other tauopathies. Among the aggregate species, granular-shaped oligomers are recently reported as toxic species and associated with neuronal loss. Many interests have been focused on the reducing of these neurotoxic oligomers in tauopathies. It has been approved that peptides NAP (NAPVSIPQ) and SAL (SALLRSIPA), snipped from activity-dependent neurotrophic protein (ADNP) and activity-dependent neurotrophic factor (ADNF), protect brain against a wide range of toxins in neurodegenerative models. The neuroprotection mechanisms of NAP and SAL are under investigation. We report here that the aggregation pathway of human tau protein, in the presence of NAP or SAL, could be affected and moved toward the less granular-shaped species. Fluorophore binding assays, kinetic parameters and circular dichroism records, showed the presence of unusual aggregated species upon treatment with NAP or SAL, as well as hydrophobicity studies. Also, sizing and morphological investigation of aggregates, using dynamic scattered light and Atomic Force Microscopy, elucidated a significant reduction of granular-shaped oligomers under 50 nm. Furthermore, immunospecific detection of oligomers in SH-SY5Y cell line, using flow cytometric assessment supported our results. We conclude that one of the possible mechanisms of neuronal protection by NAP or SAL could be the attenuation of granular-shaped oligomeric tau under stress condition.

Several flexible and rigid analogs of 4H-1,2,4-triazoles (compounds 8a-g and 9a-g) bearing trimethoxyphenyl pharmacophoric unit, were designed and synthesized as potential anticancer agents. The in vitro cytotoxic assay indicated that both flexible and rigid analogs (8 and 9, respectively) can potentially inhibit the growth of cancerous cells (A549, MCF7, and SKOV3), with IC50 values less than 5.0 µM. Furthermore, compounds 10a-l as regional isomers of compounds 9 exhibited remarkable cytotoxic activity with IC50 values ranging from 0.30 to 5.0 µM. The rigid analogs 9a, 10h and 10k were significantly more potent than etoposide against MCF7, SKOV3 and A549 cells, respectively. These compounds showed high selectivity towards cancer cells over normal cells, as they had no significant cytotoxicity against L929 cells. In addition, the representative compounds 9a and 10h could inhibit the tubulin polymerization at micro-molar levels. By determining changes in the colchicine-tubulin fluorescence, it was suggested that compound 10h could bind to the tubulin at the colchicine pocket. The molecular docking study further confirmed the inhibitory activity of promising compounds 9a, 10h and 10k on tubulin polymerization through binding to the colchicine-binding site.

Objective(s): Crocin, as the main carotenoid of saffron, has shown anti-tumor activity both in vitro and in vivo. Crocin might interact with cellular proteins and modulate their functions, but the exact target of this carotenoid and the other compounds of the saffron have not been discovered yet. Microtubular proteins, as one of the most important proteins inside the cells, have several functions in nearly all kinds of cellular processes. The aim of this study was to investigate whether crocin affects microtubule polymerization and tubulin structure. Materials and Methods: Microtubules were extracted from sheep brains after two cycles of temperature-dependant assembly-disassembly in the polymerization buffer (PMG). Then phosphocellulose P11 column was used to prepare MAP-free tubulin. Turbidimetric assay of microtubules was performed by incubation of tubulins at 37 ºC in PIPES buffer. To investigate the intrinsic fluorescence spectra of tubulins, the emission spectra of tryptophans was monitored. To test the interaction of crocin with tubulin in more details, ANS has been used. Results: Crocin extremely affected the tubulin polymerization and structure. Ultraviolet spectroscopy indicated that crocin increased polymerization of microtubules by nearly a factor of two. Fluorescence spectroscopic data also pointed to significant conformational changes of tubulin. Conclusion: We showed that crocin increased tubulin polymerization and microtubule nucleation rate and this effect was concentration dependant. After entering cell, crocin can modulate cellular proteins and their functions. Concerning the results of this study, crocin would be able to affect several cell processes through interaction with tubulin proteins or microtubules.