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Complications of chronic non-healing wounds led to the emergence of nanotechnology-based therapies to enhance healing, facilitate tissue repair, and prevent wound-related complications like infections. Here, we design alpha lipoic acid (ALA) conjugated hexagonal boron nitride (hBN) and boron carbide (B4C) nanoparticles (NPs) to enhance wound healing in human dermal fibroblast (HDFa) cell culture and characterize its antimicrobial properties against Staphylococcus aureus (S. aureus, gram positive) and Escherichia coli (E. coli, gram negative) bacterial strains. ALA molecules are integrated onto hBN and C4B NPs through esterification procedure, and molecular characterizations are performed by using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and UV-vis spectroscopy. Wound healing and antimicrobial properties are investigated via the use of cell viability assays, scratch test, oxidative stress, and antimicrobial activity assays. Based on our analysis, we observe that ALA-conjugated hBN NPs have the highest wound-healing feature and antimicrobial activity compared to ALA-B4C. On the other hand, hBN, ALA-B4C, and ALA compounds showed promising regenerative and antimicrobial properties. Also, we find that ALA conjugation enhances wound healing and antimicrobial potency of hBN and B4C NPs. We conclude that the ALA-hBN conjugate is a potential candidate to stimulate regeneration process for injuries., QC 20230321

Prosthetic lipoyl groups are essential for the metabolic activity of several multienzyme complexes in most organisms. In plants, octanoyltransferase (LIP2) and lipoyl synthase (LIP1) enzymes in the mitochondria and plastids participate in the de novo synthesis of lipoic acid, and in the attachment of the lipoyl cofactors to their specific targets. In plastids, the lipoylated pyruvate dehydrogenase complex catalyzes the synthesis of the acetyl-CoA that is required for de novo fatty acid synthesis. Since lipoic acid transport across plastid membranes has not been demonstrated, these organelles require specific plastidial LIP1 and LIP2 activities for the in situ synthesis of this cofactor. Previously, one essential LIP1 enzyme and two redundant LIP2 enzymes have been identified within Arabidopsis chloroplasts. In this study, two plastidial sunflower (Helianthus annuus L.) LIP2 genes (HaLIP2p1 and HaLIP2p2) were identified, cloned and characterized. The expression of these genes in different tissues was studied and the tertiary structure of the peptides they encode was modeled by protein docking. These genes were overexpressed in Escherichia coli and their impact on bacterial fatty acid synthesis was studied. Finally, transgenic Arabidopsis plants overexpressing HaLIP2p1 were generated and their seed lipid profiles analyzed. The lipid composition of the transgenic seeds, particularly their TAG species, differed from that of wild-type plants, revealing a relationship between lipoic acid synthesis and the accumulation of storage lipids in Arabidopsis seeds.

Prosthetic lipoyl groups are essential for the metabolic activity of several multienzyme complexes in most organisms. In plants, octanoyltransferase (LIP2) and lipoyl synthase (LIP1) enzymes in the mitochondria and plastids participate in the de novo synthesis of lipoic acid, and in the attachment of the lipoyl cofactors to their specific targets. In plastids, the lipoylated pyruvate dehydrogenase complex catalyzes the synthesis of the acetyl-CoA that is required for de novo fatty acid synthesis. Since lipoic acid transport across plastid membranes has not been demonstrated, these organelles require specific plastidial LIP1 and LIP2 activities for the in situ synthesis of this cofactor. Previously, one essential LIP1 enzyme and two redundant LIP2 enzymes have been identified within Arabidopsis chloroplasts. In this study, two plastidial sunflower (Helianthus annuus L.) LIP2 genes (HaLIP2p1 and HaLIP2p2) were identified, cloned and characterized. The expression of these genes in different tissues was studied and the tertiary structure of the peptides they encode was modeled by protein docking. These genes were overexpressed in Escherichia coli and their impact on bacterial fatty acid synthesis was studied. Finally, transgenic Arabidopsis plants overexpressing HaLIP2p1 were generated and their seed lipid profiles analyzed. The lipid composition of the transgenic seeds, particularly their TAG species, differed from that of wild-type plants, revealing a relationship between lipoic acid synthesis and the accumulation of storage lipids in Arabidopsis seeds.

Prosthetic lipoyl groups are essential for the metabolic activity of several multienzyme complexes in most organisms. In plants, octanoyltransferase (LIP2) and lipoyl synthase (LIP1) enzymes in the mitochondria and plastids participate in the de novo synthesis of lipoic acid, and in the attachment of the lipoyl cofactors to their specific targets. In plastids, the lipoylated pyruvate dehydrogenase complex catalyzes the synthesis of the acetyl-CoA that is required for de novo fatty acid synthesis. Since lipoic acid transport across plastid membranes has not been demonstrated, these organelles require specific plastidial LIP1 and LIP2 activities for the in situ synthesis of this cofactor. Previously, one essential LIP1 enzyme and two redundant LIP2 enzymes have been identified within Arabidopsis chloroplasts. In this study, two plastidial sunflower (Helianthus annuus L.) LIP2 genes (HaLIP2p1 and HaLIP2p2) were identified, cloned and characterized. The expression of these genes in different tissues was studied and the tertiary structure of the peptides they encode was modeled by protein docking. These genes were overexpressed in Escherichia coli and their impact on bacterial fatty acid synthesis was studied. Finally, transgenic Arabidopsis plants overexpressing HaLIP2p1 were generated and their seed lipid profiles analyzed. The lipid composition of the transgenic seeds, particularly their TAG species, differed from that of wild-type plants, revealing a relationship between lipoic acid synthesis and the accumulation of storage lipids in Arabidopsis seeds.

Prosthetic lipoyl groups are essential for the metabolic activity of several multienzyme complexes in most organisms. In plants, octanoyltransferase (LIP2) and lipoyl synthase (LIP1) enzymes in the mitochondria and plastids participate in the de novo synthesis of lipoic acid, and in the attachment of the lipoyl cofactors to their specific targets. In plastids, the lipoylated pyruvate dehydrogenase complex catalyzes the synthesis of the acetyl-CoA that is required for de novo fatty acid synthesis. Since lipoic acid transport across plastid membranes has not been demonstrated, these organelles require specific plastidial LIP1 and LIP2 activities for the in situ synthesis of this cofactor. Previously, one essential LIP1 enzyme and two redundant LIP2 enzymes have been identified within Arabidopsis chloroplasts. In this study, two plastidial sunflower (Helianthus annuus L.) LIP2 genes (HaLIP2p1 and HaLIP2p2) were identified, cloned and characterized. The expression of these genes in different tissues was studied and the tertiary structure of the peptides they encode was modeled by protein docking. These genes were overexpressed in Escherichia coli and their impact on bacterial fatty acid synthesis was studied. Finally, transgenic Arabidopsis plants overexpressing HaLIP2p1 were generated and their seed lipid profiles analyzed. The lipid composition of the transgenic seeds, particularly their TAG species, differed from that of wild-type plants, revealing a relationship between lipoic acid synthesis and the accumulation of storage lipids in Arabidopsis seeds.

Hybrids based on an aza-analogue of CGP37157, a mitochondrial Na+/Ca2+ exchanger antagonist, and lipoic acid were obtained in order to combine in a single molecule the antioxidant and NRF2 induction properties of lipoic acid and the neuroprotective activity of CGP37157. The four possible enantiomers of the hybrid structure were synthesized by using as the key step a fully diastereoselective reduction induced by Ellman’s chiral auxiliary. After computational druggability studies that predicted good ADME profiles and blood–brain permeation for all compounds, the DPPH assay showed moderate oxidant scavenger capacity. Following a cytotoxicity evaluation that proved the compounds to be non-neurotoxic at the concentrations tested, they were assayed for NRF2 induction capacity and for anti-inflammatory properties and measured by their ability to inhibit nitrite production in the lipopolysaccharide-stimulated BV2 microglial cell model. Moreover, the compounds were studied for their neuroprotective effect in a model of oxidative stress achieved by treatment of SH-SY5Y neuroblastoma cells with the rotenone–oligomycin combination and also in a model of hyperphosphorylation induced by treatment with okadaic acid. The stereocenter config- uration showed a critical influence in NRF2 induction properties, and also in the neuroprotection against oxidative stress experiment, leading to the identification of the compound with S and R configuration as an interesting hit with a good neuroprotective profile against oxidative stress and hyperphosphorylation, together with a relevant anti-neuroinflammatory activity. This interesting multitarget profile will be further characterized in future work.

Fatty acids in mitochondria, in sensu stricto, arise either as β-oxidation substrates imported via the carnitine shuttle or through de novo synthesis by the mitochondrial fatty acid synthesis (mtFAS) pathway. Defects in mtFAS or processes involved in the generation of the mtFAS product derivative lipoic acid (LA), including iron-sulfur cluster synthesis required for functional LA synthase, have emerged only recently as etiology for neurodegenerative disease. Intriguingly, mtFAS deficiencies very specifically affect CNS function, while LA synthesis and attachment defects have a pleiotropic presentation beyond neurodegeneration. Typical mtFAS defect presentations include optical atrophy, as well as basal ganglia defects associated with dystonia. The phenotype display of patients with mtFAS defects can resemble the presentation of disorders associated with coenzyme A (CoA) synthesis. A recent publication links these processes together based on the requirement of CoA for acyl carrier protein maturation. MtFAS defects, CoA synthesis- as well as Fe-S cluster-deficiencies share lack of LA as a common symptom.

Lipoic acid (LA, 6,8-dithiooctanoic acid) is a sulfur containing coenzyme essential for the activity of several key enzymes involved in oxidative and single carbon metabolism in most bacteria and eukaryotes. LA is synthetized by the concerted activity of the octanoyltransferase (LIP2, EC 2.3.1.181) and lipoyl synthase (LIP1, EC 2.8.1.8) enzymes. In plants, pyruvate dehydrogenase (PDH), 2-oxoglutarate dehydrogenase or glycine decarboxylase are essential complexes that need to be lipoylated. These lipoylated enzymes and complexes are located in the mitochondria, while PDH is also present in plastids where it provides acetyl-CoA for de novo fatty acid biosynthesis. As such, lipoylation of PDH could regulate fatty acid synthesis in both these organelles. In the present work, the sunflower LIP1 and LIP2 genes (HaLIP1m and HaLIP2m) were isolated sequenced, cloned, and characterized, evaluating their putative mitochondrial location. The expression of these genes was studied in different tissues and protein docking was modeled. The genes were also expressed in Escherichia coli and Arabidopsis thaliana, where their impact on fatty acid and glycerolipid composition was assessed. Lipidomic studies in Arabidopsis revealed lipid remodeling in lines overexpressing these enzymes and the involvement of both sunflower proteins in the phenotypes observed is discussed in the light of the results obtained.

Lipoic acid (LA, 6,8-dithiooctanoic acid) is a sulfur containing coenzyme essential for the activity of several key enzymes involved in oxidative and single carbon metabolism in most bacteria and eukaryotes. LA is synthetized by the concerted activity of the octanoyltransferase (LIP2, EC 2.3.1.181) and lipoyl synthase (LIP1, EC 2.8.1.8) enzymes. In plants, pyruvate dehydrogenase (PDH), 2-oxoglutarate dehydrogenase or glycine decarboxylase are essential complexes that need to be lipoylated. These lipoylated enzymes and complexes are located in the mitochondria, while PDH is also present in plastids where it provides acetyl-CoA for de novo fatty acid biosynthesis. As such, lipoylation of PDH could regulate fatty acid synthesis in both these organelles. In the present work, the sunflower LIP1 and LIP2 genes (HaLIP1m and HaLIP2m) were isolated sequenced, cloned, and characterized, evaluating their putative mitochondrial location. The expression of these genes was studied in different tissues and protein docking was modeled. The genes were also expressed in Escherichia coli and Arabidopsis thaliana, where their impact on fatty acid and glycerolipid composition was assessed. Lipidomic studies in Arabidopsis revealed lipid remodeling in lines overexpressing these enzymes and the involvement of both sunflower proteins in the phenotypes observed is discussed in the light of the results obtained.

Lipoic acid (LA, 6,8-dithiooctanoic acid) is a sulfur containing coenzyme essential for the activity of several key enzymes involved in oxidative and single carbon metabolism in most bacteria and eukaryotes. LA is synthetized by the concerted activity of the octanoyltransferase (LIP2, EC 2.3.1.181) and lipoyl synthase (LIP1, EC 2.8.1.8) enzymes. In plants, pyruvate dehydrogenase (PDH), 2-oxoglutarate dehydrogenase or glycine decarboxylase are essential complexes that need to be lipoylated. These lipoylated enzymes and complexes are located in the mitochondria, while PDH is also present in plastids where it provides acetyl-CoA for de novo fatty acid biosynthesis. As such, lipoylation of PDH could regulate fatty acid synthesis in both these organelles. In the present work, the sunflower LIP1 and LIP2 genes (HaLIP1m and HaLIP2m) were isolated sequenced, cloned, and characterized, evaluating their putative mitochondrial location. The expression of these genes was studied in different tissues and protein docking was modeled. The genes were also expressed in Escherichia coli and Arabidopsis thaliana, where their impact on fatty acid and glycerolipid composition was assessed. Lipidomic studies in Arabidopsis revealed lipid remodeling in lines overexpressing these enzymes and the involvement of both sunflower proteins in the phenotypes observed is discussed in the light of the results obtained.

Lipoic acid (LA, 6,8-dithiooctanoic acid) is a sulfur containing coenzyme essential for the activity of several key enzymes involved in oxidative and single carbon metabolism in most bacteria and eukaryotes. LA is synthetized by the concerted activity of the octanoyltransferase (LIP2, EC 2.3.1.181) and lipoyl synthase (LIP1, EC 2.8.1.8) enzymes. In plants, pyruvate dehydrogenase (PDH), 2-oxoglutarate dehydrogenase or glycine decarboxylase are essential complexes that need to be lipoylated. These lipoylated enzymes and complexes are located in the mitochondria, while PDH is also present in plastids where it provides acetyl-CoA for de novo fatty acid biosynthesis. As such, lipoylation of PDH could regulate fatty acid synthesis in both these organelles. In the present work, the sunflower LIP1 and LIP2 genes (HaLIP1m and HaLIP2m) were isolated sequenced, cloned, and characterized, evaluating their putative mitochondrial location. The expression of these genes was studied in different tissues and protein docking was modeled. The genes were also expressed in Escherichia coli and Arabidopsis thaliana, where their impact on fatty acid and glycerolipid composition was assessed. Lipidomic studies in Arabidopsis revealed lipid remodeling in lines overexpressing these enzymes and the involvement of both sunflower proteins in the phenotypes observed is discussed in the light of the results obtained.

Lipoic acid (LA, 6,8-dithiooctanoic acid) is a sulfur containing coenzyme essential for the activity of several key enzymes involved in oxidative and single carbon metabolism in most bacteria and eukaryotes. LA is synthetized by the concerted activity of the octanoyltransferase (LIP2, EC 2.3.1.181) and lipoyl synthase (LIP1, EC 2.8.1.8) enzymes. In plants, pyruvate dehydrogenase (PDH), 2-oxoglutarate dehydrogenase or glycine decarboxylase are essential complexes that need to be lipoylated. These lipoylated enzymes and complexes are located in the mitochondria, while PDH is also present in plastids where it provides acetyl-CoA for de novo fatty acid biosynthesis. As such, lipoylation of PDH could regulate fatty acid synthesis in both these organelles. In the present work, the sunflower LIP1 and LIP2 genes (HaLIP1m and HaLIP2m) were isolated sequenced, cloned, and characterized, evaluating their putative mitochondrial location. The expression of these genes was studied in different tissues and protein docking was modeled. The genes were also expressed in Escherichia coli and Arabidopsis thaliana, where their impact on fatty acid and glycerolipid composition was assessed. Lipidomic studies in Arabidopsis revealed lipid remodeling in lines overexpressing these enzymes and the involvement of both sunflower proteins in the phenotypes observed is discussed in the light of the results obtained.

Novel reduction-responsive hyaluronic acid-chitosan-lipoic acid nanoparticles (HACSLA-NPs) were designed and synthesized for effective treatment of breast cancer by targeting Cluster of Differentiation 44 (CD44)-overexpressing cells and reduction-triggered 17α- Methyltestosterone (MT) release for systemic delivery. The effectiveness of these nanoparticles was investigated by different assays, including release rate, 3-(4,5-Dimethylthiazol-2-Yl)-2,5- Diphenyltetrazolium Bromide (MTT), lactate dehydrogenase (LDH), caspase-3 activity, Rhodamine 123 (RH-123), and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). In vitro experiments revealed that Methyltestosterone/Hyaluronic acid-chitosan-lipoic acid nanoparticles (MT/HACSLA-NPs) illustrated a sustained drug release in the absence of glutathione (GSH), while the presence of GSH led to fast MT release. HACSLA-NPs also showed high cellular internalization via CD44 receptors, quick drug release inside the cells, and amended cytotoxicity against positive CD44 BT-20 breast cancer cell line as opposed to negative CD44, Michigan Cancer Foundation-7 (MCF-7) cell line. These findings supported that these novel reduction-responsive NPs can be promising candidates for efficient targeted delivery of therapeutics in cancer therapy. © 2020 by the authors.

To date, drugs that hit a single target are inadequate for the treatment of neurodegenerative diseases, such as Alzheimer's or Parkinson's diseases. The development of multitarget ligands, able to interact with the different pathways involved in the progession of these disorders, represents a great challenge for medicinal chemists. In this context, we report here the synthesis and biological evaluation of phenol-lipoyl hybrids (SV1-13), obtained via a linking strategy, to take advantage of the synergistic effect due to the antioxidant portions and anti-amyloid properties of the single constituents present in the hybrid molecule. Biological results showed that SV5 and SV10 possessed the best protective activity against Aβ1-42 induced neurotoxicity in differentiated SH-SY5Y cells. SV9 and SV10 showed remarkable antioxidant properties due to their ability to counteract the damage caused by H2O2 in SHSY-5Y-treated cells. Hovewer, SV5, showing moderate antioxidant and good neuroprotective activities, resulted the best candidate for further experiments since it also resulted stable both simulated and plasma fluids., QC 20200306

High arsenic (As) levels in food and drinking water, or under some occupational conditions, can precipitate chronic toxicity and in some cases cancer. Millions of people are exposed to unacceptable amounts of As through drinking water and food. Highly exposed individuals may develop acute, subacute, or chronic signs of poisoning, characterized by skin lesions, cardiovascular symptoms, and in some cases, multi-organ failure. Inorganic arsenite(III) and organic arsenicals with the general formula R-As2+ are bound tightly to thiol groups, particularly to vicinal dithiols such as dihydrolipoic acid (DHLA), which together with some seleno-enzymes constitute vulnerable targets for the toxic action of As. In addition, R-As2+-compounds have even higher affinity to selenol groups, e.g., in thioredoxin reductase that also possesses a thiol group vicinal to the selenol. Inhibition of this and other ROS scavenging seleno-enzymes explain the oxidative stress associated with arsenic poisoning. The development of chelating agents, such as the dithiols BAL (dimercaptopropanol), DMPS (dimercapto-propanesulfonate) and DMSA (dimercaptosuccinic acid), took advantage of the fact that As had high affinity towards vicinal dithiols. Primary prevention by reducing exposure of the millions of people exposed to unacceptable As levels should be the prioritized strategy. However, in acute and subacute and even some cases with chronic As poisonings chelation treatment with therapeutic dithiols, in particular DMPS appears promising as regards alleviation of symptoms. In acute cases, initial treatment with BAL combined with DMPS should be considered.

Increasingly, evidence is accumulating pointing at a protective role of a healthy diet at decreasing the risk of Alzheimer's disease. To test the effectiveness of nutritional components, the following food-derived compounds: curcumin alone (curcumin), curcumin combined with (-)epigallocatechin-3-gallate (EGCG), docosahexaenoic acid (DHA) and α-lipoic acid (ALA) (curcumin + EDA), or a combination of EGCG, DHA and ALA (EDA) were assessed in male Tg2576 transgenic mice on amyloid plaque load, amyloid levels (Aβ40/Aβ42, but not oligomers due to tissue limitations), microglial activation and memory using the contextual and cued fear conditioning test. The combination diet EDA, resulted in the strongest reduction of amyloid plaque load in both the cortical (p < .0001) and hippocampal (p < .0001) areas of the Tg2576 mouse brain, along with lower Aβ

Acyl carrier protein (ACP) is a principal partner in the cytosolic and mitochondrial fatty acid synthesis (FAS) pathways. The active form holo-ACP serves as FAS platform, using its 4′-phosphopantetheine group to present covalently attached FAS intermediates to the enzymes responsible for the acyl chain elongation process. Mitochondrial unacylated holo-ACP is a component of mammalian mitoribosomes, and acylated ACP species participate as interaction partners in several ACP-LYRM (leucine-tyrosine-arginine motif)-protein heterodimers that act either as assembly factors or subunits of the electron transport chain and Fe-S cluster assembly complexes. Moreover, octanoyl-ACP provides the C8 backbone for endogenous lipoic acid synthesis. Accumulating evidence suggests that mtFAS-generated acyl-ACPs act as signaling molecules in an intramitochondrial metabolic state sensing circuit, coordinating mitochondrial acetyl-CoA levels with mitochondrial respiration, Fe-S cluster biogenesis and protein lipoylation.

Tato práce je zaměřena na vývoj roubovaných kopolymerů na bázi kyseliny hyaluronové určených pro kosmetický průmysl. Teoretická část je zaměřena na problematiku kyseliny hyaluronové a různých typů antioxidantů, používaných k její kopolymeraci, a také možností charakterizace kopolymerů na bázi kyseliny hyaluronové. V praktické části je popsána příprava derivátů HA a jejich charakterizace pomocí vybraných analytických a biologických metod., This thesis is focuses on the development of graft copolymers based on hyaluronan for cosmetics. The theoretical part is focused on the problems of hyaluronic acid and various types of antioxidants used for its copolymerization, as well as the possibility of characterizing copolymers based on hyaluronic acid. The practical part describes the preparation of HA derivatives and their characterization using selected analytical and biological methods., Fakulta chemicko-technologická, Diplomantka přednesla výsledky své diplomové práce a zodpověděla dotazy členů komise., Dokončená práce s úspěšnou obhajobou

Lipoic acid (LA) is used extensively as a therapeutic agent for the treatment of various diseases. Many methods have been reported for the determination of LA plasma levels and its metabolites after its supplementation, but available information concerning endogenous plasma levels is still scarce. Studies which directly focused on determining the endogenous plasma levels provided highly controversial results, <4.9 nmol/L or 143.7–197.0 nmol/L. The main aim of this study was to verify the levels of free LA in the plasma of 40 individuals (17 women, 23 men). This group was nonsupplemented with LA and met the conditions for incorporation into the blood donors register. We measured the levels of LA using an HPLC method with very sensitive coulometric detection after previous sample preparation including deproteination and solid‐phase extraction with a Phenyl cartridge. Our limit of detection was 1.85 nmol/L and was better than the values reported in studies that directly focused on determining the endogenous plasma levels of LA: 2.4 and 4.9 nmol/L respectively. However, the levels of free LA in the plasma of nonsupplemented voluntary blood donors were not detectable in all cases. The presented results of our study show that endogenous concentrations of LA are <1.85 nmol/L., Kyselina lipoová je široce používána pro léčbu různých onemocnění. Pro stanovení kyseliny lipoové a jejich metabolitů v lidské plazmě po suplementaci bylo publikováno mnoho metod, ale dostupné informace o endogenních plazmatických koncentracích jsou stále nedostatečné. Studie přímo zaměřené na stanovení endogenních hladin v plazmě poskytly vysoce rozporuplné výsledky, <4,9 nmol/l nebo 143,7–197,0 nmol/l. Hlavním cílem studie bylo ověřit hladiny volné kysleiny lipoové v plazmě 40 dobrovolníků (17 žen, 23 můžů). Tato skupina byla nesuplementována kyselinou lipoovou a splnila podmínky pro začlenění do registru dobrovolných dárců krve. Měřili jsme hladiny kyseliny lipoové pomocí HPLC s velmi citlivou coulometrickou detekcí po předchozí přípravě vzorku, která zahrnuje deproteinaci a extrakci na pevné fázi s Phenylovou cartridge. Limit detekce naší metody byl 1,85 nmol/l a byl lepší než hodnoty publikované ve studiích, které byly přímo zaměřeny na stanovení endogenních plazmatických hladin kyseliny lipoové: 2,4 a 4,9 nmol/l. Nicméně ve všech případech byly hladiny volné kyseliny lipoové v plazmě nesuplementovaných dárců krve nedetekovatelné. Výsledky naší studie ukazují, že endogenní koncentrace kyseliny lipoové jsou menší než 1,85 nmol/l.

A comprehensive comparative evaluation of the ability of L-17 compound (2-morpholino-5-phenyl-1,3,4-thiadiazine) and antioxidant lipoic acid (LA) to correct blood cytokine levels, metabolic disorders and morphological alterations in pancreas in alloxan-induced diabetes was performed for the first time, using an experimental in vivo model. All the tested compounds have been found to correct hyperglycemia and decreased accumulation of glycated blood proteins. The tested L-17 compound belongs to the 1,3,4-thiadiazine series and is able to correct metabolic disorders occurring in alloxan-induced diabetes comparable to activity of LA antioxidant. However, L-17 reduces the cytokine levels to the values of intact animals, that preventing development of systemic inflammatory response which causes damage of target organs in diabetes mellitus.

NFU1 deficiency is a rare metabolic disorder affecting iron-sulfur cluster synthesis, an essential pathway for lipoic acid-dependent enzymatic activities and mitochondrial respiratory chain complexes. It is a little-known cause of pulmonary arterial hypertension (PAH), while PAH is a prominent feature of the disease. We herein report on a female infant diagnosed as having idiopathic PAH since 1 month of age, who did not respond to bosentan plus sildenafil. NFU1 deficiency was only suggested and confirmed at 10 months of age when she demonstrated neurological deterioration along with high glycine levels in body fluids. Unexplained PAH in early infancy should prompt clinicians to perform amino acid chromatography searching for high glycine levels. Early recognition will avoid further invasive procedures and enable appropriate genetic counselling to be offered. No effective treatment is currently able to prevent the fatal course of this metabolic condition.

Hearing loss, the most common neurological disorder and the fourth leading cause of years lived with disability, can have profound effects on quality of life. The impact of this "invisible disability," with significant consequences, economic and personal, is most substantial in low- and middle-income countries, where >80% of affected people live. Given the importance of hearing for communication, enjoyment, and safety, with up to 500 million affected globally at a cost of nearly $800 billion/year, research on new approaches toward prevention and treatment is attracting increased attention. The consequences of noise pollution are largely preventable, but irreversible hearing loss can result from aging, disease, or drug side effects. Once damage occurs, treatment relies on hearing aids and cochlear implants. Preventing, delaying, or reducing some degree of hearing loss may be possible by avoiding excessive noise and addressing major contributory factors such as cardiovascular risk. However, given the magnitude of the problem, these interventions alone are unlikely to be sufficient. Recent advances in understanding principal mechanisms that govern hearing function, together with new drug discovery paradigms designed to identify efficacious therapies, bode well for pharmaceutical intervention. This review surveys various causes of loss of auditory function and discusses potential neurological underpinnings, including mitochondrial dysfunction. Mitochondria mitigate cell protection, survival, and function and may succumb to cumulative degradation of energy production and performance; the end result is cell death. Energy-demanding neurons and vestibulocochlear hair cells are vulnerable to mitochondrial dysfunction, and hearing impairment and deafness are characteristic of neurodegenerative mitochondrial disease phenotypes. Beyond acting as cellular powerhouses, mitochondria regulate immune responses to infections, and studies of this phenomenon have aided in identifyin

Lipoic acid is synthesized by a remarkably atypical pathway in which the cofactor is assembled on its cognate proteins. An octanoyl moiety diverted from fatty acid synthesis is covalently attached to the acceptor protein, and sulfur insertion at carbons 6 and 8 of the octanoyl moiety form the lipoyl cofactor. Covalent attachment of this cofactor is required for function of several central metabolism enzymes, including the glycine cleavage H protein (GcvH). In Bacillus subtilis, GcvH is the sole substrate for lipoate assembly. Hence lipoic acid-requiring 2-oxoacid dehydrogenase (OADH) proteins acquire the cofactor only by transfer from lipoylated GcvH. Lipoyl transfer has been argued to be the primordial pathway of OADH lipoylation. The Escherichia coli pathway where lipoate is directly assembled on both its GcvH and OADH proteins, is proposed to have arisen later. Because roughly 3 billion years separate the divergence of these bacteria, it is surprising that E. coli GcvH functionally substitutes for the B. subtilis protein in lipoyl transfer. Known and putative GcvHs from other bacteria and eukaryotes also substitute for B. subtilis GcvH in OADH modification. Because glycine cleavage is the primary GcvH role in ancestral bacteria that lack OADH enzymes, lipoyl transfer is a “moonlighting” function: that is, development of a new function while retaining the original function. This moonlighting has been conserved in the absence of selection by some, but not all, GcvH proteins. Moreover, Aquifex aeolicus encodes five putative GcvHs, two of which have the moonlighting function, whereas others function only in glycine cleavage.

Hearing loss, the most common neurological disorder and the fourth leading cause of years lived with disability, can have profound effects on quality of life. The impact of this "invisible disability," with significant consequences, economic and personal, is most substantial in low- and middle-income countries, where >80% of affected people live. Given the importance of hearing for communication, enjoyment, and safety, with up to 500 million affected globally at a cost of nearly $800 billion/year, research on new approaches toward prevention and treatment is attracting increased attention. The consequences of noise pollution are largely preventable, but irreversible hearing loss can result from aging, disease, or drug side effects. Once damage occurs, treatment relies on hearing aids and cochlear implants. Preventing, delaying, or reducing some degree of hearing loss may be possible by avoiding excessive noise and addressing major contributory factors such as cardiovascular risk. However, given the magnitude of the problem, these interventions alone are unlikely to be sufficient. Recent advances in understanding principal mechanisms that govern hearing function, together with new drug discovery paradigms designed to identify efficacious therapies, bode well for pharmaceutical intervention. This review surveys various causes of loss of auditory function and discusses potential neurological underpinnings, including mitochondrial dysfunction. Mitochondria mitigate cell protection, survival, and function and may succumb to cumulative degradation of energy production and performance; the end result is cell death. Energy-demanding neurons and vestibulocochlear hair cells are vulnerable to mitochondrial dysfunction, and hearing impairment and deafness are characteristic of neurodegenerative mitochondrial disease phenotypes. Beyond acting as cellular powerhouses, mitochondria regulate immune responses to infections, and studies of this phenomenon have aided in identifyin

Cílem této práce bylo (a) vyvinout vhodnou metodu pro stanovení endogenních hladin kyseliny lipoové, (b) ověřit, zda je tato metoda vhodná i pro stanovení hladin kyseliny lipoové po suplementaci, (c) určit cytotoxicitu kyseliny lipoové na erytrocyty, (d) ověřit význam homocysteinu jako biomarkeru v klinické praxi, získat obecný přehled o celkovém metabolismu methioninu u pacientů s onemocněním koronárních arterii a ověřit okamžitý vliv perkutánní koronární intervence na hladiny methioninu a jeho metabolitů. (a) Cílem bylo vyvinout vhodnou metodu pro stanovení hladin volné kyseliny lipoové. Jedná se o vysokoúčinnou kapalinovou chromatografii s elektrochemickou detekcí. Vzorky krve byly získány od 40 dobrovolných darců, kteří splňovali podmínky pro zapsání do registru dárců. Tito dárci nebyli suplementováni kyselinou lipoovou. Při stanovení kyseliny lipoové v plasmě byly vzorky krve odstředěny a získaná plasma byla deproteinována acetonitrilem. Po odstředění následovala extrakce na pevné fázi a kyselina lipoová byla eluována z kolonky methanolem. Eluát byl odpařen do sucha v atmosféře dusíku. Odparek byl rozpuštěn ve směsi acetonitrilu a deionizované vody, po filtraci byl vzorek dávkován na analytickou kolonu s vázanou reverzní fází. Limit detekce a kvantifikace této metody byl 1,85 a 5,18 nmol/l. Dosáhli jsme nižší hodnoty meze detekce v porovnání s předchozími studiemi (2,4 a 4,9 nmol/l), které se zabývaly stanovením volné kyseliny lipoové u nesuplementovaných jedinců. Nicméně. i přesto jsme hladiny kyseliny lipoové v plasmě u všech 40 dobrovolných dárců nedetekovali. Výsledky naší studie ukazuji, že endogenní koncentrace volné kyseliny lipoové v plasmě jsou pravděpodobně nižší než 1,85 nmol/l. (b) Tato metoda byla využita k ověření hladin kyseliny lipoové v plasmě. u suplementovaných dobrovolných dárců a je tak vhodná pro studie zabývající se stanovením hladin kyseliny lipoové u suplementovaných pacientů. (c) Byl sledován vliv kyseliny lipoové na životaschopnost (v, The aims of this thesis are: (a) the development of a suitable method for the determination endogenous levels of lipoic acid, (b) the verification of a possibility to use the method for determining the lipoic acid levels after supplementation, (c) the determination of lipoic acid cytotoxicity for erythrocytes, and (d) to verify the importance of homocysteine as a biomarker in clinical practice. Moreover, the aim is to obtain a general overview about the whole methionine metabolism for patients, suffering from coronary artery disease at different degrees of severity, as well as?n to verify the immediate effect of a percutaneous coronary intervention on the methionine level and its metabolites. (a) The aim was to develop a suitable method in order to determine the endogenous levels of free lipoic acid using a high-performance liquid chromatography method with a very sensitive coulometric detection. Plasma samples were collected from 40 voluntary blood donors. This group was non-supplemented with lipoic acid and met the preconditions in for being included to the blood donorsˇ? registry. A blood sample was collected into a tube containing ethylene diamintetraacetic acid as an anticoagulant and the obtained plasma was deproteinized with acetonitrile. A solid phase extraction was used for the extraction. The samples were eluted with methanol and the eluate was evaporated to dryness using a gentle nitrogen stream. The residue was re-dissolved in a mixture of acetonitrile/water. After filtration, the sample was injected into an analytical column with reversed-phase. The limit of detection and the limit of quantification values were 1.85 and 5.18 nmol/l. The limit of detection was better than in previous studies: 2.4 nmo/l and 4.9 nmol/l respectively. However, the levels of LA in the plasma of the 40 non-supplemented voluntary blood donors were not detectable in all cases. The results of our study show that endogenous concentrations of LA are less than1.85 nmol/l. (b) This m, Fakulta chemicko-technologická

Kyselina lipoová je silný antioxidant, který se používá jako doplněk stravy při léčbě řady onemocnění, která jsou spojena s oxidačním stresem, například diabetes a kardiovaskulární onemocnění. Tento článek se zabývá analytickými metodami, které se využívají pro stanovení kyseliny lipoové v různých vzorcích., Lipoic acid is powerful antioxidant which is used as a dietary supplement to treat a lot of disorders associated with the oxidative stress and was found to be useful in patients with diabetes and cardiovascular diseases. The article deals with analytical methods used for the determination of lipoic acid in various samples.

Eye disease is one of the primary medical conditions that requires attention and therapeutic intervention in ageing populations worldwide. Further, the global burden of diabetes and obesity, along with heart disease, all lead to secondary manifestations of ophthalmic distress. Therefore, there is increased interest in developing innovative new approaches that target various mechanisms and sequelae driving conditions that result in adverse vision. The research challenge is even greater given that the terrain of eye diseases is difficult to landscape into a single therapeutic theme. This report addresses the burden of eye disease due to mitochondrial dysfunction, including antioxidant, autophagic, epigenetic, mitophagic, and other cellular processes that modulate the biomedical end result. In this light, we single out lipoic acid as a potent known natural activator of these pathways, along with alternative and potentially more effective conjugates, which together harness the necessary potency, specificity, and biodistribution parameters required for improved therapeutic outcomes.

Eye disease is one of the primary medical conditions that requires attention and therapeutic intervention in ageing populations worldwide. Further, the global burden of diabetes and obesity, along with heart disease, all lead to secondary manifestations of ophthalmic distress. Therefore, there is increased interest in developing innovative new approaches that target various mechanisms and sequelae driving conditions that result in adverse vision. The research challenge is even greater given that the terrain of eye diseases is difficult to landscape into a single therapeutic theme. This report addresses the burden of eye disease due to mitochondrial dysfunction, including antioxidant, autophagic, epigenetic, mitophagic, and other cellular processes that modulate the biomedical end result. In this light, we single out lipoic acid as a potent known natural activator of these pathways, along with alternative and potentially more effective conjugates, which together harness the necessary potency, specificity, and biodistribution parameters required for improved therapeutic outcomes.

Alpha-lipoic acid (LA) is a powerful antioxidant. LA has two enantiomers, R(+)-LA (R-LA) and S(-)-LA (S-LA). Of these, R-LA is naturally occurring and an essential cofactor in energy metabolism. R-LA treatment has been reported to affect glucose metabolism in rat hepatoma cells. This study analyzed the time course of metabolite levels in LA-treated cultured H4IIEC3 rat hepatoma cells, including a specific evaluation of the effect of R-LA and the enantioselectivity of LA. Principal component analysis showed that this experiment was well designed to observe enantioselectivity. R-LA treatment was found to inhibit the glycolysis and Thr-Gly-Ser pathways, as well as lactic acid production, leading to the inhibition of gluconeogenesis in starved H4IIEC3 cells. This study may provide mechanistic insight into how R-LA induces apoptosis in hepatoma cells. © Copyright 2017, Mary Ann Liebert, Inc. and Korean Society of Food Science and Nutrition 2017., Embargo Period 12 months

Kyselina lipoová je přirozeně se vyskytující osmiuhlíkatá sloučenina. Ve své molekule má dva atomy síry a jedno chirální centrum. Vyskytuje se ve dvou izomerech jako S-lipoová a R-lipoová kyselina. Její redukovanou formou je kyselina dihydrolipoová. Kyselina lipoová má silné antioxidační účinky a terapeuticky se podává například při diabetu. Ve vysokých koncentracích dokáže kyselina lipoová vyvolat apoptózu nádorových buněk, a proto se o ní uvažuje jako o protinádorovém léčivu. Kromě apoptózy nádorových buněk ale vyvolává apoptózu i u nenádorových buněk a tím může vyvolat poškození ledvin a jiných orgánů. Cílem této práce bylo prozkoumat působení kyseliny lipoové na krevní buňky. Důvodem bylo zejména literárně podložené podezření, že způsobuje poškození erytrocytů. Zjistili jsme, že kyselina lipoová v koncentracích využívaných k léčbě diabetu nepoškozuje erytrocyty. Ve vysokých koncentracích, které by se podávaly proti nádorovým buňkám, způsobuje úbytek erytrocytů, což by mohlo vést k anémii., Lipoic acid is a naturally occurring eight carbon compound. It has two sulphur atoms and one chiral center in its molecule. It exists as two isomers, S-lipoic and R-lipoic acid. Its reduced form is called dihydrolipoic acid. Lipoic acid has strong antioxidant effects and it is therapeutically used for example in diabetes. At high concentrations, lipoic acid is able to induce tumor cell apoptosis and it is therefore considered to be an anticancer drug. Except tumor cell apoptosis, it also induces apoptosis in non-tumor cells and this may cause damage to the kidneys and other organs. The aim of this thesis was to examine the effect of lipoic acid on blood cells. The reason for this examination was the suspicion from the literature that lipoic acid causes damage of erythrocytes. We have found that lipoic acid at the concentrations used in the treatment of diabetes does not damage the erythrocytes. At high concentrations that would be used against tumor cells, it causes a decrease in erythrocytes, which could lead to anemia., Fakulta chemicko-technologická, 1. Prezentace výsledků diplomové práce. 2. Diskuze k posudku vedoucího a oponenta diplomové práce. 3. Studentka zodpověděla všechny dotazy a připomínky.

[EN] Primary objective: The aim of this study was to investigate the reparative potential of a polymeric scaffold designed for brain tissue repair in combination with lipoic acid. Research design: Histological, cytological and structural analysis of a combined treatment after a brain cryo-injury model in rats. Methods and procedures: Adult Wistar rats were subjected to cryogenic brain injury. A channelled-porous scaffold of ethyl acrylate and hydroxyethylacrylate, p(EA-co-HEA) was grafted into cerebral penumbra alone or combined with intraperitoneal LA administration. Histological and cytological evaluation was performed after 15 and 60 days and structural magnetic resonance (MRI) assessment was performed at 2 and 6 months after the surgery. Main outcomes and results: The scaffold was suitable for the establishment of different cellular types. The results obtained suggest that this strategy promotes blood vessels formation, decreased microglial response and neuron migration, particularly when LA was administrated. Conclusions: These evidences demonstrated that the combination of a channelled polymer scaffold with LA administration may represent a potential treatment for neural tissue repair after brain injury.

Los complementos alimenticios son alimentos cuyo fin es complementar la dieta normal y que consisten en fuentes concentradas de nutrientes (vitaminas y minerales) o de otras sustancias que tienen un efecto nutricional o fisiológico, en forma simple o combinada. Los complementos se comercializan en forma dosificada, se entregan al consumidor final únicamente preenvasados. En ningún caso, deben sustituir al uso de medicamentos sin una supervisión médica adecuada. Sólo deben utilizarse para complementar la dieta y, de forma general, su uso no es necesario si se sigue una dieta variada y equilibrada, a la que no pueden reemplazar. En España los complementos alimenticios están regulados por el Real Decreto 1487/2009 que traspuso a la legislación española la Directiva 2002/46/CE relativa a la aproximación de las legislaciones de los estados miembros en materia de complementos alimenticios. Sin embargo, actualmente sólo está regulado el uso de vitaminas y minerales, por lo que se ha solicitado al Comité Científico que realice una valoración de la propuesta de autorización de la utilización de determinadas sustancias distintas de vitaminas y minerales en la fabricación de complementos alimenticios. Las sustancias propuestas por la Agencia Española de Consumo, Seguridad Alimentaria y Nutrición (AECOSAN) son: ácido L-aspártico, L-citrulina, glicina, L-prolina, L-serina, L-arginina-L-aspartato, L-lisina-L-aspartato, L-lisina-L-glutamato, N-acetil-L-cisteína, N-acetil-L-metionina, hidroximetilbu- tirato, ácido lipoico, Monascus purpureus, carbón activo y lactulosa. El Comité Científico ha valorado cada propuesta, analizando las características y fuentes de cada sustancia, así como la nutrición, metabolismo y seguridad y ha concluido, en cada caso, si la presentada por la AECOSAN era aceptable desde el punto de vista de su seguridad en su uso como complemento alimenticio. En ningún caso, la evaluación realizada supone un aval de la eficacia biológica de las sustancias y dosis va, Food supplements are foods, the purpose of which is to supplement the normal diet and which consist of concentrated nutrient sources (vitamins and minerals) or other substances with a nutritional or physiological effect, alone or in combination. The supplements are marketed in dosage form and are only supplied to the end consumer prepacked. In no event should they replace the use of medicines without suitable medical supervision. They should only be used to supplement the diet and, on the whole, their usage is not required if the individual has a varied and balanced diet, which cannot be replaced. In Spain, food supplements are regulated by Royal Decree 1487/2009, which transposed Directive 2002/46/EC on the approximation of the laws of the Member States relating to food supplements into Spanish law. However, only the use of vitamins and minerals is currently regulated. Therefore the Scientific Committee has been asked to make an assessment of the proposal to authorise certain substances other than vitamins and minerals in the manufacture of food supplements. The substances proposed by the Spanish Agency for Consumer Affairs, Food Safety and Nutrition (AECOSAN) are food supplements, L-aspartic acid, L-citrulline, glycine, L-proline, L-serine, L-arginine-L-aspar- tate, L-lysine L-aspartate, L-lysine-L-glutamate, N-acetyl-L-cysteine, N-acetyl-L-methionine, hidro- xymethylbutyrate, lipoic acid, Monascus purpureus, activated carbon and lactulose. The Scientific Committee has assessed each proposal, analysing the characteristics and sources of each substance, and the nutrition, metabolism and safety and has concluded, in each case, whether that submitted by the AECOSAN is acceptable from a safety viewpoint for use as a food supplement. In no event is the assessment intended as a guarantee of the biological efficiency of the substances and doses assessed. The Scientific Committee states that, in any case individuals undergoing medical treatment must seek medical advice as

Los complementos alimenticios son alimentos cuyo fin es complementar la dieta normal y que consisten en fuentes concentradas de nutrientes (vitaminas y minerales) o de otras sustancias que tienen un efecto nutricional o fisiológico, en forma simple o combinada. Los complementos se comercializan en forma dosificada, se entregan al consumidor final únicamente preenvasados. En ningún caso, deben sustituir al uso de medicamentos sin una supervisión médica adecuada. Sólo deben utilizarse para complementar la dieta y, de forma general, su uso no es necesario si se sigue una dieta variada y equilibrada, a la que no pueden reemplazar. En España los complementos alimenticios están regulados por el Real Decreto 1487/2009 que traspuso a la legislación española la Directiva 2002/46/CE relativa a la aproximación de las legislaciones de los estados miembros en materia de complementos alimenticios. Sin embargo, actualmente sólo está regulado el uso de vitaminas y minerales, por lo que se ha solicitado al Comité Científico que realice una valoración de la propuesta de autorización de la utilización de determinadas sustancias distintas de vitaminas y minerales en la fabricación de complementos alimenticios. Las sustancias propuestas por la Agencia Española de Consumo, Seguridad Alimentaria y Nutrición (AECOSAN) son: ácido L-aspártico, L-citrulina, glicina, L-prolina, L-serina, L-arginina-L-aspartato, L-lisina-L-aspartato, L-lisina-L-glutamato, N-acetil-L-cisteína, N-acetil-L-metionina, hidroximetilbu- tirato, ácido lipoico, Monascus purpureus, carbón activo y lactulosa. El Comité Científico ha valorado cada propuesta, analizando las características y fuentes de cada sustancia, así como la nutrición, metabolismo y seguridad y ha concluido, en cada caso, si la presentada por la AECOSAN era aceptable desde el punto de vista de su seguridad en su uso como complemento alimenticio. En ningún caso, la evaluación realizada supone un aval de la eficacia biológica de las sustancias y dosis va, Food supplements are foods, the purpose of which is to supplement the normal diet and which consist of concentrated nutrient sources (vitamins and minerals) or other substances with a nutritional or physiological effect, alone or in combination. The supplements are marketed in dosage form and are only supplied to the end consumer prepacked. In no event should they replace the use of medicines without suitable medical supervision. They should only be used to supplement the diet and, on the whole, their usage is not required if the individual has a varied and balanced diet, which cannot be replaced. In Spain, food supplements are regulated by Royal Decree 1487/2009, which transposed Directive 2002/46/EC on the approximation of the laws of the Member States relating to food supplements into Spanish law. However, only the use of vitamins and minerals is currently regulated. Therefore the Scientific Committee has been asked to make an assessment of the proposal to authorise certain substances other than vitamins and minerals in the manufacture of food supplements. The substances proposed by the Spanish Agency for Consumer Affairs, Food Safety and Nutrition (AECOSAN) are food supplements, L-aspartic acid, L-citrulline, glycine, L-proline, L-serine, L-arginine-L-aspar- tate, L-lysine L-aspartate, L-lysine-L-glutamate, N-acetyl-L-cysteine, N-acetyl-L-methionine, hidro- xymethylbutyrate, lipoic acid, Monascus purpureus, activated carbon and lactulose. The Scientific Committee has assessed each proposal, analysing the characteristics and sources of each substance, and the nutrition, metabolism and safety and has concluded, in each case, whether that submitted by the AECOSAN is acceptable from a safety viewpoint for use as a food supplement. In no event is the assessment intended as a guarantee of the biological efficiency of the substances and doses assessed. The Scientific Committee states that, in any case individuals undergoing medical treatment must seek medical advice as

Los complementos alimenticios son alimentos cuyo fin es complementar la dieta normal y que consisten en fuentes concentradas de nutrientes (vitaminas y minerales) o de otras sustancias que tienen un efecto nutricional o fisiológico, en forma simple o combinada. Los complementos se comercializan en forma dosificada, se entregan al consumidor final únicamente preenvasados. En ningún caso, deben sustituir al uso de medicamentos sin una supervisión médica adecuada. Sólo deben utilizarse para complementar la dieta y, de forma general, su uso no es necesario si se sigue una dieta variada y equilibrada, a la que no pueden reemplazar. En España los complementos alimenticios están regulados por el Real Decreto 1487/2009 que traspuso a la legislación española la Directiva 2002/46/CE relativa a la aproximación de las legislaciones de los estados miembros en materia de complementos alimenticios. Sin embargo, actualmente sólo está regulado el uso de vitaminas y minerales, por lo que se ha solicitado al Comité Científico que realice una valoración de la propuesta de autorización de la utilización de determinadas sustancias distintas de vitaminas y minerales en la fabricación de complementos alimenticios. Las sustancias propuestas por la Agencia Española de Consumo, Seguridad Alimentaria y Nutrición (AECOSAN) son: ácido L-aspártico, L-citrulina, glicina, L-prolina, L-serina, L-arginina-L-aspartato, L-lisina-L-aspartato, L-lisina-L-glutamato, N-acetil-L-cisteína, N-acetil-L-metionina, hidroximetilbu- tirato, ácido lipoico, Monascus purpureus, carbón activo y lactulosa. El Comité Científico ha valorado cada propuesta, analizando las características y fuentes de cada sustancia, así como la nutrición, metabolismo y seguridad y ha concluido, en cada caso, si la presentada por la AECOSAN era aceptable desde el punto de vista de su seguridad en su uso como complemento alimenticio. En ningún caso, la evaluación realizada supone un aval de la eficacia biológica de las sustancias y dosis va, Food supplements are foods, the purpose of which is to supplement the normal diet and which consist of concentrated nutrient sources (vitamins and minerals) or other substances with a nutritional or physiological effect, alone or in combination. The supplements are marketed in dosage form and are only supplied to the end consumer prepacked. In no event should they replace the use of medicines without suitable medical supervision. They should only be used to supplement the diet and, on the whole, their usage is not required if the individual has a varied and balanced diet, which cannot be replaced. In Spain, food supplements are regulated by Royal Decree 1487/2009, which transposed Directive 2002/46/EC on the approximation of the laws of the Member States relating to food supplements into Spanish law. However, only the use of vitamins and minerals is currently regulated. Therefore the Scientific Committee has been asked to make an assessment of the proposal to authorise certain substances other than vitamins and minerals in the manufacture of food supplements. The substances proposed by the Spanish Agency for Consumer Affairs, Food Safety and Nutrition (AECOSAN) are food supplements, L-aspartic acid, L-citrulline, glycine, L-proline, L-serine, L-arginine-L-aspar- tate, L-lysine L-aspartate, L-lysine-L-glutamate, N-acetyl-L-cysteine, N-acetyl-L-methionine, hidro- xymethylbutyrate, lipoic acid, Monascus purpureus, activated carbon and lactulose. The Scientific Committee has assessed each proposal, analysing the characteristics and sources of each substance, and the nutrition, metabolism and safety and has concluded, in each case, whether that submitted by the AECOSAN is acceptable from a safety viewpoint for use as a food supplement. In no event is the assessment intended as a guarantee of the biological efficiency of the substances and doses assessed. The Scientific Committee states that, in any case individuals undergoing medical treatment must seek medical advice as

Los complementos alimenticios son alimentos cuyo fin es complementar la dieta normal y que consisten en fuentes concentradas de nutrientes (vitaminas y minerales) o de otras sustancias que tienen un efecto nutricional o fisiológico, en forma simple o combinada. Los complementos se comercializan en forma dosificada, se entregan al consumidor final únicamente preenvasados. En ningún caso, deben sustituir al uso de medicamentos sin una supervisión médica adecuada. Sólo deben utilizarse para complementar la dieta y, de forma general, su uso no es necesario si se sigue una dieta variada y equilibrada, a la que no pueden reemplazar. En España los complementos alimenticios están regulados por el Real Decreto 1487/2009 que traspuso a la legislación española la Directiva 2002/46/CE relativa a la aproximación de las legislaciones de los estados miembros en materia de complementos alimenticios. Sin embargo, actualmente sólo está regulado el uso de vitaminas y minerales, por lo que se ha solicitado al Comité Científico que realice una valoración de la propuesta de autorización de la utilización de determinadas sustancias distintas de vitaminas y minerales en la fabricación de complementos alimenticios. Las sustancias propuestas por la Agencia Española de Consumo, Seguridad Alimentaria y Nutrición (AECOSAN) son: ácido L-aspártico, L-citrulina, glicina, L-prolina, L-serina, L-arginina-L-aspartato, L-lisina-L-aspartato, L-lisina-L-glutamato, N-acetil-L-cisteína, N-acetil-L-metionina, hidroximetilbu- tirato, ácido lipoico, Monascus purpureus, carbón activo y lactulosa. El Comité Científico ha valorado cada propuesta, analizando las características y fuentes de cada sustancia, así como la nutrición, metabolismo y seguridad y ha concluido, en cada caso, si la presentada por la AECOSAN era aceptable desde el punto de vista de su seguridad en su uso como complemento alimenticio. En ningún caso, la evaluación realizada supone un aval de la eficacia biológica de las sustancias y dosis va, Food supplements are foods, the purpose of which is to supplement the normal diet and which consist of concentrated nutrient sources (vitamins and minerals) or other substances with a nutritional or physiological effect, alone or in combination. The supplements are marketed in dosage form and are only supplied to the end consumer prepacked. In no event should they replace the use of medicines without suitable medical supervision. They should only be used to supplement the diet and, on the whole, their usage is not required if the individual has a varied and balanced diet, which cannot be replaced. In Spain, food supplements are regulated by Royal Decree 1487/2009, which transposed Directive 2002/46/EC on the approximation of the laws of the Member States relating to food supplements into Spanish law. However, only the use of vitamins and minerals is currently regulated. Therefore the Scientific Committee has been asked to make an assessment of the proposal to authorise certain substances other than vitamins and minerals in the manufacture of food supplements. The substances proposed by the Spanish Agency for Consumer Affairs, Food Safety and Nutrition (AECOSAN) are food supplements, L-aspartic acid, L-citrulline, glycine, L-proline, L-serine, L-arginine-L-aspar- tate, L-lysine L-aspartate, L-lysine-L-glutamate, N-acetyl-L-cysteine, N-acetyl-L-methionine, hidro- xymethylbutyrate, lipoic acid, Monascus purpureus, activated carbon and lactulose. The Scientific Committee has assessed each proposal, analysing the characteristics and sources of each substance, and the nutrition, metabolism and safety and has concluded, in each case, whether that submitted by the AECOSAN is acceptable from a safety viewpoint for use as a food supplement. In no event is the assessment intended as a guarantee of the biological efficiency of the substances and doses assessed. The Scientific Committee states that, in any case individuals undergoing medical treatment must seek medical advice as

Los complementos alimenticios son alimentos cuyo fin es complementar la dieta normal y que consisten en fuentes concentradas de nutrientes (vitaminas y minerales) o de otras sustancias que tienen un efecto nutricional o fisiológico, en forma simple o combinada. Los complementos se comercializan en forma dosificada, se entregan al consumidor final únicamente preenvasados. En ningún caso, deben sustituir al uso de medicamentos sin una supervisión médica adecuada. Sólo deben utilizarse para complementar la dieta y, de forma general, su uso no es necesario si se sigue una dieta variada y equilibrada, a la que no pueden reemplazar. En España los complementos alimenticios están regulados por el Real Decreto 1487/2009 que traspuso a la legislación española la Directiva 2002/46/CE relativa a la aproximación de las legislaciones de los estados miembros en materia de complementos alimenticios. Sin embargo, actualmente sólo está regulado el uso de vitaminas y minerales, por lo que se ha solicitado al Comité Científico que realice una valoración de la propuesta de autorización de la utilización de determinadas sustancias distintas de vitaminas y minerales en la fabricación de complementos alimenticios. Las sustancias propuestas por la Agencia Española de Consumo, Seguridad Alimentaria y Nutrición (AECOSAN) son: ácido L-aspártico, L-citrulina, glicina, L-prolina, L-serina, L-arginina-L-aspartato, L-lisina-L-aspartato, L-lisina-L-glutamato, N-acetil-L-cisteína, N-acetil-L-metionina, hidroximetilbu- tirato, ácido lipoico, Monascus purpureus, carbón activo y lactulosa. El Comité Científico ha valorado cada propuesta, analizando las características y fuentes de cada sustancia, así como la nutrición, metabolismo y seguridad y ha concluido, en cada caso, si la presentada por la AECOSAN era aceptable desde el punto de vista de su seguridad en su uso como complemento alimenticio. En ningún caso, la evaluación realizada supone un aval de la eficacia biológica de las sustancias y dosis va, Food supplements are foods, the purpose of which is to supplement the normal diet and which consist of concentrated nutrient sources (vitamins and minerals) or other substances with a nutritional or physiological effect, alone or in combination. The supplements are marketed in dosage form and are only supplied to the end consumer prepacked. In no event should they replace the use of medicines without suitable medical supervision. They should only be used to supplement the diet and, on the whole, their usage is not required if the individual has a varied and balanced diet, which cannot be replaced. In Spain, food supplements are regulated by Royal Decree 1487/2009, which transposed Directive 2002/46/EC on the approximation of the laws of the Member States relating to food supplements into Spanish law. However, only the use of vitamins and minerals is currently regulated. Therefore the Scientific Committee has been asked to make an assessment of the proposal to authorise certain substances other than vitamins and minerals in the manufacture of food supplements. The substances proposed by the Spanish Agency for Consumer Affairs, Food Safety and Nutrition (AECOSAN) are food supplements, L-aspartic acid, L-citrulline, glycine, L-proline, L-serine, L-arginine-L-aspar- tate, L-lysine L-aspartate, L-lysine-L-glutamate, N-acetyl-L-cysteine, N-acetyl-L-methionine, hidro- xymethylbutyrate, lipoic acid, Monascus purpureus, activated carbon and lactulose. The Scientific Committee has assessed each proposal, analysing the characteristics and sources of each substance, and the nutrition, metabolism and safety and has concluded, in each case, whether that submitted by the AECOSAN is acceptable from a safety viewpoint for use as a food supplement. In no event is the assessment intended as a guarantee of the biological efficiency of the substances and doses assessed. The Scientific Committee states that, in any case individuals undergoing medical treatment must seek medical advice as

Kyselina lipoová je přírodně se vyskytující osmiuhlíkatá disulfidická sloučenina. Má dva optické izomery R--kyselinu lipoovou a S--kyselinu lipoovou. Jejich racemická směs se používá v terapii pacientů s diabetem. V poslední době se zkoumají také její protinádorové účinky. Optimalizovali jsme metodu vysokoúčinné kapalinové chromatografie s elektrochemickou detekcí ke stanovení kyseliny lipoové v erytrocytech. Stanovení kyseliny lipoové v erytrocytech má význam k získání poznatků o jejím transportu přes buněčnou membránu nebo o její kumulaci v erytrocytech při dlouhodobějším podávání. Stanovení může také přispět k řešení problematiky týkající se indukce apoptózy erytrocytů u pacientů suplementovaných kyselinou lipoovou. Pomocí systému xCELLigence a průtokové cytometrie bylo v naší práci zjištěno, že určité dávky kyseliny lipoové u buněčných linií karcinomu prsu snižují buněčnou proliferaci. U nádorové linie nemalobuněčného karcinomu plic způsobuje zástavu buněčného cyklu. Došli jsme k závěru, že využití kyseliny lipoové je v protinádorové terapii námi zkoumaných typů nádorů závislé na dávce. Může tak být využita spíše v nižších dávkách jako podpůrný prostředek, protože dávky vedoucí až k apoptóze jsou poměrně vysoké a mohou vést k poškození funkce ledvin., Lipoic acid is a naturally occurring eight carbon disulfide compound. It has two optical isomers, R--lipoic acid and S--lipoic acid. Their mixture is used for therapy in patients with diabetes mellitus. Anticancer effects of lipoic acid also are explored recently. We have optimalized the method of high performance liquid chromatography with electrochemical detection for the determination of lipoic acid in erythrocytes. The determination of lipoic acid is important to gain knowledge about the transport through the erythrocyte membrane and its accumulation in erythrocytes during prolonged administration. This determination can also contribute to solving problems related to induction of apoptosis erythrocytes in patients supplemented with lipoic acid. Using xCELLigence system and flow cytometry we found out that specific dose of lipoic acid reduces proliferation of cells of breast carcinoma. Lipoic acid caused arrest of cell cycle in lung adenocarcinoma cell line. We can conclude, that lipoic acid anticancer use is a dose dependent. Lipoic acid in a low dosage can be use as a supporting agent only, becouse apoptotic dose is a high and can cause renal damage., Katedra biologických a biochemických věd, 1. Prezentace výsledků diplomové práce.2. Diskuze k posudku vedoucího diplomové práce. 3. Studentka zodpověděla vaechny dotazy a připomínky k DP.

Cílem této práce je shrnout dostupné a nejnovější informace o klinickém významu kyseliny lipoové se zaměřením na její antioxidační vlastnosti. V další části je cílem zpracovat dostupné informace o zapojení kyseliny lipoové do mechanizmů ovlivňující vznik aterosklerózy. V neposlední řadě je věnována pozornost novinkám v metodice stanovení kyseliny lipoové v lidské plazmě., The aim of this paper is to summarize the latest information available and the clinical significance of lipoic acid to focus on its antioxidant properties. The next part is to process the available information on the involvement of lipoic acid in the mechanisms influencing the development of atherosclerosis. Finally, attention is given to new developments in the methodology for determination of lipoic acid in human plasma., Katedra biologických a biochemických věd, 1. Prezentace výsledků bakalářské práce. 2. Diskuze k posudku vedoucího bakalářské práce. 3. Studentka zodpověděla všechny dotazy a připomínky k BP.

V této diplomové práci se zabývám optimalizací metody vysokoúčinné kapalinové chromatografie s elektrochemickou detekcí na principu coulometrie, která by byla vhodnou a relativně dostupnou metodou pro analytické stanovení kyseliny lipoové v lidské plasmě. Navazuje na předchozí diplomové práce, u kterých se podařilo měřit kyselinu lipoovou u suplementovaných jedinců. My jsme se pokusili optimalizovat tuto metodu pro stanovení endogenních hladin kyseliny lipoové u jedinců nesuplementovaných. Z našich měření však vyplývá, že je tato metoda vhodná pouze pro stanovení kyseliny lipoové u suplementovaných jedinců., This thesis deals with optimization of the high performance liquid chromatography method using coulometry based electrochemical detection, which would be convenient and reasonable technique for analytical determination of the lipoic acid in human blood plasma. It follows previous theses, where it was possible to determine oxidized form of the lipoic acid for supplemented individuals. Our attempt was to optimize this method to determine endogenous levels of the lipoic acid for unsupplemented individuals. Our measurements show that this method is only suitable for determination of lipoic acid for supplemented individuals., Katedra biologických a biochemických věd, 1. Prezentace výsledků diplomové práce 2. Diskuze k posudkům vedoucího a oponenta diplomové práce 3. Diplomant zodpověděl všechny dotazy a připomínky k DP

Increased ventilation is a general response to shock that may help to maintain cardiac output by improving venous return to the heart. The central stimulus for this increase in ventilation involves the production of S-nitroso-L-cysteine from more ubiquitous precursor S-nitrothiols in the medulla of the brain. Changes in dietary nitrite and nitrate have been shown to increase tissue levels of S-nitrosothiols and to improve survival in models of myocardial infarction. We hypothesize that increased dietary intake of nitrite or nitrate will enhance the ventilatory response in hemorrhage and thereby increase the time of survival. The goal of this project was to adequate methodology for the detection of S-nitrosylated proteins in tissues. A sensitive and specific method for the detection of S-nitrosylated proteins in tissues based on photolysis/immuno-spin-trapping analysis of DMPO thioethers has been developed. The applicability of the method for the quantitative assessments of Snitrosylated proteins in tissues has been tested and confirmed. The ability of dihydrolipoic acid and lipoic acid (LA) plus lipoamide dehydrogenase and NADH to denitrosate S-nitrosocaspase 3 (CASP-SNO) and regulate apoptosis in HepG2 cells has been established.

Kyselina lipoová je sloučenina přírodního původu. Její obě formy, oxidovaná i redukovaná, si zachovávají antioxidační vlastnosti a mají protizánětlivé účinky in vivo a in vitro. Bylo prokázáno, že tento silný antioxidant hraje významnou roli při léčbě mnoha onemocnění, jejichž vývoj souvisí se zvýšeným oxidačním stresem např. diabetes mellitus a s ním spojené komplikace. V současné době se studie, zabývající se léčbou pomocí kyseliny lipoové, zaměřují na kardiovaskulární onemocnění. Kyselina lipoová totiž brání rozvoji aterosklerotických plátů snížením počtu zánětlivých buněk, snižuje obsah tuků a upravuje pružnost cévních stěn. Pro analýzu kyseliny lipoové lze využít mnoha metod. Avšak většina z nich je nevyhovující z důvodu jejich nedostatku citlivosti a specifity, potřeby nákladného analytického vybavení a časové náročnosti na přípravu vzorku. Cílem naší práce bylo pokusit se vypracovat vhodnou metodu, pomocí které bychom byli schopni simultánního stanovení oxidované i redukované formy kyseliny lipoové. Tento proces je velmi složitý a problematický a skládá se z jednotlivých dílčích kroků. Podařilo se nám určit vhodné podmínky redukce tak, aby byla maximální. Předmětem dalšího zkoumání bude zjištění stability kyseliny dihydrolipoové a zlepšení extrakce pomocí dichlormetanu., The lipoic acid is a chemical compound of the natural origin. Both of its redox forms show antioxidant properties and anti-inflammatory effects in vivo and in vitro. It was proved that the lipoic acid plays an important role in a therapy of many diseases, which are related to enhanced oxidative stress. As an example we can name diabetes mellitus and other complications related to it. There are many studies nowadays dealing with using lipoic acid as treatment of cardiovascular diseases. The reason is that lipoic acid prevents development of atherosclerotic plaques by decreasing the number of inflammatory cells, reduces the amount of fats and regulates the flexibility of vessel walls. Many methods for analyzing lipoic acid are known. However, most of them are inconvenient, because they are not enough sensitive and specific; the accessories are expensive and also preparing samples lasts long. The aim of our project was to develop an appropriate method by which we were able to simultaneous determination of oxidized and reduced forms of lipoic acid. This process is very complicated and problematic, and consists of individual steps. We were able to establish appropriate conditions to reduce to the maximum. Subject to further study will establish the stability of dihydrolipoic acid and improve the extraction using dichlormethane., Katedra biologických a biochemických věd, 1) Prezentace výsledků diplomové práce 2) Diskuze k posudkům vedoucího a oponenta diplomové práce 3) Diplomantka zodpověděla všechny dotazy a připomínky k diplomové práce, Dokončená práce s úspěšnou obhajobou

Kyselina lipoová je dithiolová sloučenina, která se používá v klinické medicíně a experimentálních modelech jako antioxidant. Zachovává si své antioxidační vlastnosti v obou jejich formách, oxidované i redukované, a reguluje recyklaci ostatních oxidovaných antioxidantů. Je stále více zřejmé, že kyselina lipoová může být velmi důležitá jako léčebný prostředek při diabetu. U diabetických pacientů užívajících kyselinu lipoovou buď intravenózně nebo perorálně bylo pozorováno blahodárné působení na regulaci hladiny glukosy. Důvodem je interakce kyseliny lipoové s regulačními prvky insulin-signální kaskády. Významné zlepšení v pozdních diabetických komplikací, zejména polyneuropatii, bylo prokázáno několika klinickými studiemi. Nynější experimenty zkoumají, zda-li může mít kyselina lipoová blahodárný vliv nejen v léčbě diabetu, ale také v prevenci kardiovaskulárního onemocnění. Kyselina lipoová upravuje pružnost cévní stěny, kdy magnetickou rezonancí a morfologickou analýzou bylo prokázáno, že snižuje rozvoj aterosklerotických plátů nejen snížením množství zánětlivých buněk, ale i obsahu tuků. Pro stanovení kyseliny lipoové existuje mnoho metod. Nicméně, většina z těchto metod není uspokojivá vzhledem k jejich nespecifitě, nedostatku citlivosti, dlouhodobé přípravě vzorku a potřebě drahých analytických zařízení. Snažili jsme se vytvořit jednoduchou a účinnou metodu pro stanovení redukované a oxidované formy kyseliny lipoové v lidské plasmě pomocí HPLC s elektrochemickou detekcí na principu coulometrie. Zjistili jsme, že metoda je použitelná pro stanovení pouze oxidované formy. Během přípravy vzorku plasmy docházelo ke ztrátám redukované formy. Jako příčinu těchto ztrát jsme zatím vyloučili deproteinaci a časovou nestabilitu při úpravě vzorku. K vyřešení tohoto problému bude třeba ještě další upravování přípravy vzorku., Lipoic acid is a disulfhydryl-containing compound used in clinical medicine and in experimental models as an antioxidant. Both reduced and oxidized forms have antioxidant properties and regulate recycling of other oxidized antioxidants. There is growing evidence that lipoic acid may be a very important diabetes therapeutic agent. In diabetic patients receiving lipoic acid ether intravenously or orally was observed improvement in glucose disposal. The reason is the interaction of lipoic acid with regulatory components of the insulinsignaling cascade. Several clinical trials showed significant improvement in late diabetic complications, especially in polyneuropathies. Current trials are investigating whether beneficial properties of lipoic acid make it an appropriate treatment not just for diabetes, but also for the preventiv cardiovascular diseases. It is known, that lipoic acid regulates the elasticity of vessel wall and Magnetic Resonance Imaging analysis and morphological analysis demonstrated that lipoic acid reduced atherosclerotic plaques by reduction not only inflammatory cell but also lipid content. Many methods are available for the analysis of lipoic acid. Nevertheless, most of these methods are not satisfactory due to their non-specificity, lack of sensitivity, long-term sample preparation and need for expensive analytical equipment. We tried to develop simple and effective method for determination of reduced and oxidized forms in human plasma by using HPLC with electrochemical detection on the principle of coulometry. We have found out that method is usable for determination of plasma level only oxidized form of lipoic acid and reduced form is eliminated during sample preparation. We can exclude time-instability and protein removing as reasons for this elimination reduced form of lipoic acid. Next examination of sample-preparation is needed for explanation this problem., Katedra biologických a biochemických věd, 1) Prezentace výsledků DP 2) Diskuze k posudkům vedoucího a oponenta DP 3) Diplomantka zodpověděla všechny dotazy a připomínky k DP, Dokončená práce s úspěšnou obhajobou

Kyselina lipoová je přírodně se vyskytující sloučenina, přítomna jako kofaktor v několika mitochondriálních enzymech, které jsou zahrnuty v metabolismu a energetické produkci. Jedná se o 8-uhlíkovou sloučeninu, obsahující dva atomy síry v dithiolanovém kruhu a skládající se ze dvou enantiomerů. Ve své volné formě je kyselina lipoová, především její redukovaná forma, kyselina dihydrolipoová, silným antioxidantem, fungujícím jako "odklizeč" reaktivních forem kyslíku. Dnes je studována zejména pro tyto antioxidační vlastnosti. Pro její analýzu je dostupných mnoho metod. Většina z nich však nejsou vyhovující kvůli jejich nespecifitě, nedostatku citlivosti, dlouhotrvající přípravě vzorku a potřeby drahého analytického vybavení. Z tohoto důvodu jsme se pokusili vyvinout jednoduchou a účinnou metodu pro její stanovení v lidské plazmě použitím HPLC s elektrochemickou detekcí na principu coulometrie. Mobilní fáze byla složená ze směsi 20 mmol/l NaH2PO4/acetonitril/metanol (70:25:5 v/v) a její průtok byl 1 ml/min. Potenciály analytické cely byly nastaveny na 450 mV a 750 mV. Analytické parametry metody jsou dostačující s detekčním limitem11,5 nmol/l. Naše metoda může být použita pro stanovení jak endogenních koncentrací kyseliny lipoové, tak i pro suplementační studie., Lipoic acid is a natural compound present as a cofactor in several mitochondrial enzymes that are involved in metabolism and energy production. It is an eight-carbon compound containing two sulphur atoms in a dithiolane ring structure and consists of two enantiomers. In its free form, lipoic acid, especially its reduced form, dihydrolipoic acid, is a powerful antioxidant, functioning as a reactive oxygen species scavenger. At present, the lipoic acid is studied primarily for its antioxidant properties. Many methods are currently available for the analysis of lipoic acid. Most of these methods are not satisfactory due to thein non-specificity, lack of sensitivity, long-term sample preparation and need for expensive analytical equipment. This is the reason for our tendery to develop simple and effective method for its determination in human plasma by using HPLC with electrochemical detection on the principle of coulometry. The mobile phase consisted of a mixture 20 mmol/l NaH2PO4/acetonitril/methanol (70:25:5 v/v) and the flow rate was 1 ml/min. Potentials of analytical cell were set to 450 mV and 750 mV. Analytical performance of this method is satisfactory with the detection limit 11.5 nmol/l. Our method can be applied for both the determination of lipoic acid in endogenous levels and for supplementation study., Katedra biologických a biochemických věd, Dokončená práce s úspěšnou obhajobou

Alzheimer's disease (AD) is a progressive neurodegenerative disorder that destroys patient memory and cognition, communication ability with the social environment and the ability to carry out daily activities. Despite extensive research into the pathogenesis of AD, a neuroprotective treatment – particularly for the early stages of disease – remains unavailable for clinical use. In this review, we advance the suggestion that lipoic acid (LA) may fulfil this therapeutic need. A naturally occurring cofactor for the mitochondrial enzymes pyruvate dehydrogenase and α-ketoglutarate dehydrogenase, LA has been shown to have a variety of properties which can interfere with the pathogenesis or progression of AD. For example, LA increases acetylcholine (ACh) production by activation of choline acetyltransferase and increases glucose uptake, thus supplying more acetyl-CoA for the production of ACh. LA chelates redox-active transition metals, thus inhibiting the formation of hydroxyl radicals and also scavenges reactive oxygen species (ROS), thereby increasing the levels of reduced glutathione. In addition, LA down-regulates the expression of redox-sensitive pro-inflammatory proteins including TNF and inducible nitric oxide synthase. Furthermore, LA can scavenge lipid peroxidation products such as hydroxynonenal and acrolein. In human plasma, LA exists in an equilibrium of free and plasma protein bound form. Up to 150 μM, it is bound completely, most likely binding to high affinity fatty acid sites on human serum albumin, suggesting that one large dose rather than continuous low doses (as provided by “slow release” LA) will be beneficial for delivery of LA to the brain. Evidence for a clinical benefit for LA in dementia is yet limited. There are only two published studies, in which 600 mg LA was given daily to 43 patients with AD (receiving a standard treatment with choline-esterase inhibitors) in an open-label study over an observation period of up to 48 months. Whereas the imp

Recorded use of pesticides in the conservation of artifacts dates back to the 16th century. Museums today are faced with a tremendous task of identification and remediation of pesticides from artifacts in order to protect museum workers and the general public. In addition, artifacts are being repatriated by Native American tribes for use in cultural ceremonies which may subject the practitioner to health risks. Arsenic and mercury salts are among the pesticides that were used that are highly persistent and toxic. The primary challenge lies in removing these hazardous and persistent metals without damaging the materials or pigments on the objects.Concentrated aqueous alpha-lipoic acid solutions were developed for removing arsenic and mercury pesticides from materials commonly used in museum artifacts. The alpha-lipoic acid solutions were reduced using natural sunlight or laboratory ultraviolet lamps to enhance the binding of arsenic. The solubility of alpha-lipoic acid in various organic and inorganic solutions was determined and environmental parameters that impact the reduction and solubility, such as pH and temperature, were examined. The kinetics of the reaction of arsenic (III) with reduced lipoic acid was examined by varying the reduced lipoic acid, base and arsenic concentration as well as temperature and stirring conditions. The results indicated that the reaction occurs at a moderate rate primarily within 8 seconds in air. The reaction is chemically rate limited enhanced at higher temperatures and lower pH. Aerobic conditions significantly decreased the extent of the reaction with increased stirring rate. This impact was minimized by using a nitrogen environment or by limiting agitation during the reaction step.The methods developed were capable of removing up to 1000 µg/cm2 arsenic (of sodium arsenite) from simulated artifacts to levels near the lower detection limit of the X-ray Fluorescence Spectrometer (1 µg/cm2) without leaving detectable residues acc

In these studies antioxidant supplementation and oxidative stress measures were the basis for determining the health and welfare of the equine endurance athlete. The first study determined that lipoic acid (LA) orally administered to horses is effective in diminishing the levels of lipid peroxidation in the plasma, and is non-toxic at a dose of 10-mg/kg body weight. The second study showed muscle leakage measured by plasma creatine kinase (CK) and aspartate aminotransferase (AST) positively correlated to oxidative stress (measured by lipid hydroperoxides) during an endurance race (Research Ride 2001; R1). Also higher plasma ascorbate (ASC) status was found in the vitamin E plus C supplemented group versus the group receiving vitamin E alone. In the third study, the Research Ride 2002 (R2) determined that horses that did not finish the ride had higher CK and AST before, during and after (P < 0.05) the ride compared to horses that finished. These results were compared to the finishers of the Old Dominion 2000 (OD) and R1 and found that oxidative stress and muscle enzymes were greater during R2 due to the difficulty of terrain and ambient temperature. A higher level of horses' fitness in OD also could have explained the diminished oxidative stress. The fourth study calculated that horses at R2 were receiving 2265 ± 114 IU/d of vitamin E in the total diet prior to the race. These levels negatively correlated to plasma CK and AST and positively correlated to plasma a-tocopherol (TOC; r = 0.21; P = 0.005) throughout the 80-km race. In the final study the LA supplemented group had similar increases in antioxidant status (TOC, ASC, and total glutathione) as the vitamin E supplemented group of horses exercising for 55 km on a treadmill to simulate an endurance race. Both groups also had lower (P < 0.050) white blood cell apoptosis throughout exercise then the control group. These studies prove the need for antioxidant supplementation, specifically vitamin E or LA, during hea

It has been proposed that senescence may be associated with changes associated with oxidative damage to macromolecules. Levels of cerebellar nitric oxide synthase (NOS) and rates of generation of cortical reactive oxygen species (ROS), have been determined in mice of various ages. Both of these parameters were significantly reduced in mice aged 9 months relative to 3-month-old mice. In order to determine whether dietary manipulation can modulate these changes, the effect of exposure of mice to differing diets incorporating various antioxidants, was examined. These diets were given to 3-month-old mice for a total period of 6 further months. The presence of melatonin (40 ppm) in the basal diet restored both NOS and ROS levels to the corresponding values found in the younger (3-month-old) group of mice while lipoic acid (1650 ppm) also restored levels of NOS to those found in 3-month-old animals. Addition of coenzyme Q (ubiquinone), 200 ppm or alpha-tocopherol (1000 ppm) to the basal diet had no effect on either NOS levels or ROS generation. These data suggest that dietary supplementation may aid in delaying onset of metabolic changes characteristic of the older brain. In behavioral testing, older (9-month-old) animals exhibited reduced motor activity and diminished recall ability on the second day of exposure to the test paradigm. While no diet altered motor activity or improved recall of older animals, lipoic acid or tocopherol treatment adversely affected place recall familiarity.

It has been proposed that senescence may be associated with changes associated with oxidative damage to macromolecules. Levels of cerebellar nitric oxide synthase (NOS) and rates of generation of cortical reactive oxygen species (ROS), have been determined in mice of various ages. Both of these parameters were significantly reduced in mice aged 9 months relative to 3-month-old mice. In order to determine whether dietary manipulation can modulate these changes, the effect of exposure of mice to differing diets incorporating various antioxidants, was examined. These diets were given to 3-month-old mice for a total period of 6 further months. The presence of melatonin (40 ppm) in the basal diet restored both NOS and ROS levels to the corresponding values found in the younger (3-month-old) group of mice while lipoic acid (1650 ppm) also restored levels of NOS to those found in 3-month-old animals. Addition of coenzyme Q (ubiquinone), 200 ppm or alpha-tocopherol (1000 ppm) to the basal diet had no effect on either NOS levels or ROS generation. These data suggest that dietary supplementation may aid in delaying onset of metabolic changes characteristic of the older brain. In behavioral testing, older (9-month-old) animals exhibited reduced motor activity and diminished recall ability on the second day of exposure to the test paradigm. While no diet altered motor activity or improved recall of older animals, lipoic acid or tocopherol treatment adversely affected place recall familiarity.

Isolated Langendorff-perfused rat hearts were subjected to a fixed period of ischemia followed by increasing periods of reperfusion for investigating the changes in the extent of ischemia-reperfusion (IR) injury and tissue levels of non-enzymatic antioxidants. Effects of schisandrin B (Sch B) and (+/-) alpha -lipoic acid (LA) pretreatment were also examined. A 40-min of ischemia (40-I) followed by 20- or 40-min of reperfusion (20-R or 40-R) caused sustainable tissue damage in isolated hearts, as indicated by the increased extent of lactate dehydrogenase (LDH) leakage and impaired contractile force. The myocardial IR injury was associated with a marked decrease in tissue ascorbic acid (V-C) level. However, myocardial reduced glutathione (GSH) and alpha -tocopherol (V-E) levels remained relatively unchanged except under a more severe IR condition (40-I, 40-R). Pretreating rats with Sch B or LA at a daily dose of 1.2 mmol/kg for 3 days protected against IR injury in isolated hearts to varying degrees. While only Sch B pretreatment could improve the recovery of contractile force, LA pretreatment produced a better inhibitory effect on LDH leakage. The protection against IR injury was associated with significant increases in myocardial V-E and V-C levels in both Sch B and LA pretreated hearts. The ensemble of results suggests that the cardioprotection afforded by Sch B or LA pretreatment may at least in part be attributed to the modulation on the interplay among non-enzymatic antioxidants under oxidative stress induced by IR.

Aging is a pleiotropic process involving genetic and environmental factors. Recently it has been demonstrated that dietary constituents may affect senescence. In the present study, adult (3 month-old) mice were fed diets supplemented with ubiquinone (coenzyme Q(10)), alpha-lipoic acid, melatonin or alpha-tocopherol for a six-month period to determine if antioxidants may reverse or inhibit the progression of certain age-associated changes in cerebral mitochondrial electron transport chain (ETS) enzyme activities. The control consisted of a group of mice maintained on a basal diet for the same period. The activity of cytochrome c oxidase (Complex IV) increased with age but melatonin supplementation restored the activity to levels of 3 month-old animals. The activity of succinate dehydrogenase (Complex II) showed no age-related changes. However, this enzyme complex was elevated, in animals supplemented with coenzyme Q(10), alpha-lipoic acid and alpha-tocopherol, above corresponding values obtained with basal diet. NADH-ubiquinone oxidoreductase (Complex I) and ubiquinol:ferricytochrome-c oxidoreductase (Complex III) activities remained unchanged.