Lipoic acid – biological activity and therapeutic potential

Mitigation of hepatic and gastric impairments induced by flunixin meglumine through co-administration with alpha lipoic acid in male rats

Long term use of Flunixin meglumine produces many gastric and hepatic hazards. The current study aimed to investigate using Alpha lipoic acid (ALA) for treating flunixin meglumine (FM)-induced liver and gastrointestinal problems in male rats. FM alternated with ALA for 14 and 56 days in the experiment. This study divided 72 male rats into six groups, 12 rats for each group. Group 1 (control) received saline and distilled water, Group 2 (ALA) received alpha lipoic acid orally at 100 mg/kg bwt, Group 3 (FM-2.5) received Flunixin meglumine subcutaneously at 2.5 mg/kg bwt, Group 4 (FM-5) received Flunixin meglumine subcutaneously, Group 5 (FM-2.5 and ALA) received FM and ALA, and Group 6 received FM and ALA. Elevated white blood cell (WBC) concentrations, ALT, AST, ALP, pro-inflammatory cytokines (NF-κB, TNF-α, HMG), malonaldehyde (MDA), and significant reductions in hepatic and gastric total antioxidant capacity (TAC) were observed. At weeks 4 and 8, FM-5-treated groups had a lower stomach index weight. These changes improved when Groups 5 and 6 used ALA and FM. ALA treatment reduced WBCs, ALT, AST, ALP, NF-κB, TNF-α, HMG, MDA, TAC, and stomach index weight gains in FM-5-treated groups. Finally, biochemical markers and stomach index volume showed liver and stomach dysfunctions in male rats after FM injections. The simultaneous administration of ALA greatly reduced these deficits, suggesting it may prevent FM-related hepatic and gastrointestinal diseases.

Enhancing Nutraceutical Efficacy: The Role of M.A.T.R.I.S. Technology in Modulating Intestinal Release of Lipoic Acid and L-Carnitine

A major challenge in developing new functional foods is effectively protecting and releasing bioactive compounds in specific body areas. The Multiform Administration Timed Release Ingredients System (M.A.T.R.I.S.) is an innovative method that coats active ingredient particles with a permeable membrane, allowing for diffusion without the presence of inactive materials. This study aimed to test how M. A. T. R. I. S. modulated the absorption and effects of two molecules: α-lipoic acid and acetyl-L-carnitine. This study examined the structures of these molecules with or without M.A.T.R.I.S. and investigated their intestinal absorption. Peripheral nervous system analyses were also conducted to confirm the ability of substances to maintain their functions in the presence of M.A.T.R.I.S. Results showed that M.A.T.R.I.S. modulated the absorption of both molecules compared to granular raw material forms (p < 0.05). Additionally, the M.A.T.R.I.S. molecules better supported peripheral nerve well-being than their granular raw material forms (p < 0.05). In conclusion, this study demonstrates that M.A.T.R.I.S. technology can be used to create innovative, safe treatments by enhancing absorption mechanisms to improve the effectiveness of substances in reaching their specific targets.

Alpha-lipoic acid alleviated intermittent hypoxia-induced myocardial injury in mice by promoting autophagy through Nrf2 signaling pathway

Obstructive sleep apnea syndrome (OSAS) is a prevalent sleep-related breathing disorder characterized by intermittent hypoxia (IH). Myocardial injury is a common complication associated with OSAS. Alpha-lipoic acid (LA), a potent antioxidant, has been utilized in various disease contexts and has demonstrated significant protective effects in myocardial infarction models. Given the limited treatment options available for OSAS-related myocardial injury, this study aimed to demonstrate the potential therapeutic effects of LA and to investigate the underlying mechanisms. IH is a widely employed method to simulate the pathophysiological conditions associated with OSAS. In vivo experiments were conducted using mice placed in a specialized hypoxic chamber to replicate IH conditions. Echocardiography indicated that exposure to IH severely impaired cardiac function. Treatment with LA activated the Nrf2 pathway and autophagy, which contributed to the improvement of cardiac function in mice with OSAS. Additionally, in vitro studies demonstrated that IH induced apoptosis and decreased cell viability in H9C2 cardiomyocytes. LA enhanced Nrf2 nuclear translocation and its downstream signaling pathways, thereby promoting autophagy, inhibiting apoptosis, and alleviating injury in H9C2 cardiomyocytes. Furthermore, in vitro inhibition of Nrf2 using ML385 reduced autophagy levels and attenuated the protective effects of LA against apoptosis in H9C2 cardiomyocytes. These findings suggest that LA may provide a promising therapeutic strategy for myocardial injury associated with OSAS. By elucidating these findings, new insights into the protective mechanisms of LA against IH-induced myocardial injury are provided, highlighting its potential as a therapeutic agent for diseases associated with OSAS.

Structural insight into the unexploited allosteric binding site of fructose 1, 6-bisphosphate aldolase from C. albicans with α-lipoic acid

The rising incidence of drug-resistant fungal infections underscores the urgent need for innovative therapeutic strategies. However, developing selective treatments remains a formidable challenge due to the similarities between humans and fungal cells. Class II fructose 1,6-bisphosphate aldolase (FBA) represents an attractive pharmacological target for the development of antifungal agents due to its crucial role in microbial survival and its absence in human. In this work, we identified α-lipoic acid (ALA), a naturally occurring compound, as a novel inhibitor of C. albicans FBA (CaFBA). The co-crystallography, enzyme inhibition assays, and site-directed mutagenesis revealed that ALA acts as a non-covalent inhibitor, binding to an unexploited allosteric site on CaFBA, distinct from the previously reported substrate-binding pocket or C292 covalent binding site. Notably, ALA selectively inhibits CaFBA, likely due to the non-conservation of the allosteric binding site, particularly S268, across species. The synergistic inhibition of C. albicans by ALA and amphotericin B highlights its therapeutic potential as part of a combined antifungal strategy. In summary, this study provides a structural basis for the design and optimization of novel CaFBA inhibitors, enhancing our understanding of FBA's role in fungal growth and establishing a foundation for developing effective antifungal therapeutics against C. albicans.

Advances in α-Lipoic Acid for Disease Prevention: Mechanisms and Therapeutic Insights

α-Lipoic acid (ALA) is a naturally occurring compound with diverse biological functions, widely distributed in animal and plant tissues. It has attracted considerable attention due to its versatile therapeutic potential. However, despite these promising prospects, the clinical application of ALA remains limited by its low bioavailability and chemical instability and an incomplete understanding of its multifaceted mechanisms across various diseases. This review provides a comprehensive overview of the biochemical properties of ALA, including its direct free-radical-scavenging activity, regeneration of endogenous antioxidants, chelation of metal ions, and modulation of inflammatory responses. We also highlight the current evidence regarding ALA's therapeutic roles and efficacy in major diseases, such as neurodegenerative disorders, lung diseases, cardiovascular diseases, and diabetes. Furthermore, recent advancements and innovative strategies in ALA-based derivatives and drug-delivery systems are summarized, emphasizing their potential to address complex diseases and the necessity for further translational studies. This review aims to provide a theoretical foundation for the rational design of ALA-based therapies, thereby supporting future clinical applications and the optimization of therapeutic strategies.

Lipoic acid as a protective agent against lipopolysaccharide and other natural toxins: a comprehensive review

Alpha-lipoic acid, also known as lipoate or lipoic acid (LA), is naturally present in the mitochondria of cells, where it functions as a cofactor for dehydrogenase enzyme complexes. It has also been reported that LA is a potent antioxidant. Not only does it scavenge free radicals directly, but it can also regenerate other essential cellular antioxidants. LA exhibits various anti-inflammatory effects and offers protection to mitochondria. Numerous studies have assessed the potential protective effects of LA against natural toxins, including lipopolysaccharides, galactosamine, mycotoxins, snake venoms, and toxins derived from cyanobacteria and plants. In general, the results of these studies indicate that LA can be effective in mitigating various toxicities, primarily due to the previously mentioned capabilities. Furthermore, novel mechanisms have been proposed for LA against specific toxins, for example, direct inactivation of secretory phospholipase A2 in some snake venoms or enhancement of p-glycoprotein activity to prevent saxitoxin entry into the neuronal cells. However, the gaps in the available data from most animal experiments conducted to date have resulted in insufficient evidence to justify further clinical evaluations of the effects of LA on human poisoning cases. Consequently, more extensive research is required to address these gaps and fully realize the therapeutic potential of this valuable substance.

Protective effects of alpha-lipoic acid on memory deficit induced by repeated doses of solifenacin in mice: the role of nitro-oxidative stress

Solifenacin (Sol) is one of the most used antimuscarinics for the treatment of bladder dysfunction and there are no conclusive studies on its effects on learning and memory after long-term use. Since substances with antioxidant action, such as alpha-lipoic acid (ALA), have shown protective action in memory deficit and Alzheimer's disease, we decided to study the effects of Sol alone or associated with ALA in behavioral tests of memory and its relation to nitro-oxidative stress in different brain areas. Mice received saline or Sol p.o. for 14 or 28 days. ALA groups received: (a) saline + ALA, (b) Sol for 14 days and Sol + ALA from the 15th to the 28th days and, (c) Sol + ALA for 28 days. Behavioral tests were performed and oxidative changes (lipid peroxidation) and nitrite in the prefrontal cortex (PFC), hippocampus (HC) and striatum (ST) were also determined. Sol produced memory alterations in the mice, reducing the step-down latency and the recognition index in the novel object recognition test. Sol also increased lipid peroxidation in PFC, HC and ST and nitrite levels in the HC. On the other hand, ALA associated with Sol was able to restrict the effects caused by Sol alone, both in relation to nitro-oxidative parameters and in relation to behavioral tests. Taken together, our data suggest that ALA can be administered as an adjunctive drug in patients requiring prolonged use of Sol to mitigate these adverse central nervous system effects. However, clinical studies need to be performed to corroborate preclinical research.

Influence of Maternal Alpha-Lipoic Acid Supplementation on Postpartum Body Weight and Metabolic Health in Rats with Obesity

We examined the influence of dietary α-lipoic acid (LA; R enantiomer) supplementation in obese-complicated pregnancies on maternal postpartum body weight and metabolic health. Forty-eight female Sprague-Dawley rats were randomized into three dietary groups throughout pre-pregnancy, gestation, and lactation: (i) a low-calorie control diet (CON); (ii) a high calorie obesity-inducing diet (HC); or (iii) the HC diet with 0.25% LA (HC+LA). Following offspring weaning, all mothers were switched to the CON diet for a postpartum period of 140 days to assess maternal body weight and markers of metabolic health. HC-fed mothers showed excessive (p < 0.05) gestational weight gain (GWG), higher (p < 0.05) postpartum body weight, reduced (p < 0.05) glycemic control (lower glucose:insulin ratio) and higher (p = 0.06) hepatic cholesterol concentration versus CON mothers. In contrast, HC+LA mothers demonstrated lower (p < 0.05) body weight throughout the experimental period compared with HC mothers, primarily due to a marked reduction in GWG. Although LA did not protect (p > 0.05) against reduced glycemic control, it did alter several aspects of lipid metabolism including reduced serum HDL-C and a lower concentration of hepatic cholesterol which was mediated partly through a reduction in low-density lipoprotein receptor expression. We conclude that maternal obesity during pregnancy leads to a longer-term detrimental impact on weight gain and glycemic control, even after switching to a low-calorie postpartum diet. Maternal LA supplementation may be able to partially offset these effects, likely by protecting against excessive GWG during pregnancy. However, further work is required to determine the consequences of reduced serum HDL-C in LA-supplemented mothers.

Lipoic Acid Enhances the Defense Capability of Citrus Fruits to Blue Mold Caused by Penicillium italicum

Blue mold caused by Penicillium italicum (P. italicum) is a major postharvest disease in citrus fruits. Lipoic acid (LA) is a potent antioxidant with biological activity that was evaluated for its inhibitory effects on P. italicum and citrus blue mold using in vitro and in vivo experiments. The results demonstrated that LA effectively suppressed the mycelial growth and spore germination of P. italicum. LA increased hydrogen peroxide levels, compromising cell membrane integrity and leading to enhanced membrane permeability, as indicated by the increased relative conductivity and decreased protein and total sugar contents in P. italicum mycelia. Furthermore, LA delayed disease progression in citrus fruits infected with P. italicum through increasing total phenol and flavonoid contents and enhancing the activities of phenylalanine ammonia lyase, polyphenol oxidase, superoxide dismutase, and peroxidase in citrus peel. Overall, LA exhibited strong antifungal activity against P. italicum and improved citrus fruit resistance to blue mold, highlighting its potential as a natural postharvest disease control agent.

α-Lipoic Acid Ameliorates Arsenic-Induced Lipid Disorders by Promoting Peroxisomal β-Oxidation and Reducing Lipophagy in Chicken Hepatocyte

Liver disease poses a significant threat to global public health, with arsenic (As) recognized as a major environmental toxin contributing to liver injury. However, the specific mechanisms and the protective effects of α-lipoic acid (LA) remain unclear. Therefore, this study employs network toxicology and network pharmacology to comprehensively analyze the hepatotoxic mechanism of As and the hepatoprotective mechanism of LA, and further verifies the mechanisms of peroxisomal β-oxidation and lipophagy in the process. The network analysis results show that As induces liver damage mainly through autophagy, apoptosis, lipid metabolism, and oxidative stress, whereas LA exerts its hepatoprotective properties mainly by regulating lipid metabolism. Further verifications find that As inhibits SIRT1 expression, activates the P53 and Notch pathways, damages mitochondria, inhibits peroxisomal β-oxidation, increases lipid accumulation, and enhances lipophagy in the liver, while LA intervention alleviates As-induced lipid accumulation and enhances lipophagy by targeting SIRT1, ameliorating mitochondrial damage, enhancing peroxisomal β-oxidation, thereby alleviating As-induced liver damage. This study further clarifies the mechanism of As hepatotoxicity and provides a theoretical basis for LA as a potential hepatoprotective agent.

Screening of Leuconostoc mesenteroides strains suitable for kimoto-style brewing of sake with high antioxidant capacity

Sake brewed using the kimoto-style exhibits high antioxidant capacity and is expected to inhibit the deterioration of sake quality due to oxidation. However, the antioxidant capacity of the added lactic acid bacteria has not been explored. We aimed to screen the lactic acid bacterium, Leuconostoc mesenteroides, with excellent brewing and antioxidant capacity, to develop sake with high antioxidant capacity. Three Le. mesenteroides strains (19-2, 19-5, and 19-23) were selected from eight screened strains based on their alcohol intolerance, growth performance in koji extract, aroma compound, and low biogenic amine production. Among these, Le. mesenteroides 19-23 exhibited a significantly higher hydrophilic-oxygen radical absorbance capacity (H-ORAC) in the culture medium than the control strain, Le. mesenteroides NBRC102481. In a medium-scale sake brewing test, sake prepared with Le. mesenteroides 19-23 had a significantly higher H-ORAC value than that prepared using the sokujo-style (without Le. mesenteroides). Additionally, metabolome analysis using capillary electrophoresis time-of-flight mass spectrometry identified ferulic acid, p-coumaric acid, 3-hydroxyanthranilic acid (3-HAA), and 6,8-thioctic acid in the main mash. High-performance liquid chromatography-based quantification revealed that antioxidants in the unrefined filtrates of the main mash prepared using the kimoto-style tended to be more abundant than in those prepared using the sokujo-style. Specifically, 3-HAA and ferulic acid were more concentrated in some unrefined filtrates of the kimoto-style than sokujo-style. In conclusion, the screened Le. mesenteroides strain demonstrated potential for brewing sake with high antioxidant capacity using the kimoto-style, offering a promising method for antioxidant-rich sake production.

Self-Assembly of a Conjugate of Lipoic Acid With a Collagen-Stimulating Pentapeptide Showing Cytocompatibility and Wound Healing Properties, and Chemical and Photolytic Disassembly

Lipoic acid is a biocompatible compound with antioxidant activity that is of considerable interest in cosmetic formulations, and the disulfide group in the N-terminal ring confers redox activity. Here, we study the self-assembly and aspects of the bioactivity of a lipopeptide (peptide amphiphile) comprising the KTTKS collagen-stimulating pentapeptide sequence conjugated to an N-terminal lipoic acid chain, lipoyl-KTTKS. Using SAXS, SANS and cryo-TEM, lipoyl-KTTKS is found to form a population of curly fibrils (wormlike micelles) above a critical aggregation concentration. Upon chemical reduction, the fibrils (and β-sheet structure) are disrupted because of the breaking of the disulfide bond, which produces dihydrolipoic acid. Lipoyl-KTTKS also undergoes photo-degradation in the presence of UV radiation. Through cell assays using fibroblasts, we found that lipoyl-KTTKS has excellent cytocompatibility across a wide concentration range, stimulates collagen production, and enhances the rate of cell coverage in a simple in vitro scratch assay of 'wound healing'. Lipoyl-KTTKS thus has several notable properties that may be useful for the development of cosmetics, cell scaffolds or tissue engineering materials.

Alpha-lipoic Acid: An Antioxidant with Anti-aging Properties for Disease Therapy

The anti-aging effects of alpha-lipoic acid (αLA), a natural antioxidant synthesized in human tissues, have attracted a growing interest in recent years. αLA is a short- -chain sulfur-containing fatty acid occurring in the mitochondria of all kinds of eukaryotic cells. Both the oxidized disulfide of αLA and its reduced form (dihydrolipoic acid, DHLA) exhibit prominent antioxidant function. The amount of αLA inside the human body gradually decreases with age resulting in various health disorders. Its lack can be compensated by supplying from external sources such as dietary supplements or medicinal dosage forms. The primary objectives of this study were the analysis of updated information on the latest two-decade research regarding the use of αLA from an anti-aging perspective. The information was collected from PubMed, Wiley Online Library, Scopus, ScienceDirect, SpringerLink, Google Scholar, and clinicaltrials.gov. Numerous in silico, in vitro, in vivo, and clinical studies revealed that αLA shows a protective role in biological systems by direct or indirect reactive oxygen/nitrogen species quenching. αLA demonstrated beneficial properties in the prevention and treatment of many age-related disorders such as neurodegeneration, metabolic disorders, different cancers, nephropathy, infertility, and skin senescence. Its preventive effects in case of Alzheimer's and Parkinson's diseases are of particular interest. Further mechanistic and clinical studies are highly recommended to evaluate the wide spectrum of αLA therapeutic potential that could optimize its dietary intake for prevention and alleviation disorders related to aging.

Lipoic Acid Nanoparticles Exert Effective Antiatherosclerosis Effects through Anti-Inflammatory and Antioxidant Pathways

Oxidative stress and inflammation are key pathological features of atherosclerotic plaques. Numerous nanomedicines have been developed to alleviate oxidative stress and reduce inflammation within plaques. However, nonbioactive carrier materials reduce the bioavailability of nanomedicines and may pose potential biological toxicity. In this study, we utilized the unique amphiphilic chemical structure of lipoic acid (LA) to prepare LA nanoparticles (LA NPs) via a self-assembly method. Leveraging the inherent anti-inflammatory and antioxidant properties of LA, these NPs were used for the treatment of atherosclerosis. In an inflammatory macrophage model, LA NPs exhibited superior anti-inflammatory activity compared to free LA. Through ultrasound imaging and pathological methods, we discovered that LA NPs demonstrated nice antiatherosclerotic effects in an atherosclerotic mice model. Immunofluorescence analysis further indicated that the antiatherosclerotic effects of LA were associated with the alleviation of oxidative stress within the plaques, reduced macrophage infiltration, and downregulation of inflammatory cytokine levels. Therefore, LA NPs offer a promising therapeutic strategy for the treatment of atherosclerosis.

Enhancing renal protection against cadmium toxicity: the role of herbal active ingredients

Background

Rapid industrialization globally has led to a notable increase in the production and utilization of metals, including cadmium (Cd), consequently escalating global metal pollution worldwide. Cd, characterized as a persistent environmental contaminant, poses significant health risks, particularly impacting human health, notably the functionality of the kidneys. The profound effects of Cd stem primarily from its limited excretion capabilities and extended half-life within the human body. Mechanisms underlying its toxicity encompass generating reactive oxygen species (ROS), disrupting calcium-signaling pathways and impairing cellular antioxidant defense mechanisms. This review focuses on the protective effects of various herbal active ingredients against Cd-induced nephrotoxicity.

Aim

This study aims to investigate the mechanisms of action of herbal active ingredients, including ant-oxidative, anti-inflammatory and anti-apoptotic pathways, to elucidate potential therapeutic strategies for reducing nephrotoxicity caused by Cd exposure.

Methods

A comprehensive search of scientific databases, including Web of Science, PubMed, Scopus and Google Scholar, used relevant keywords to identify studies published up to October 2024.

Results

Research illustrates that herbal active ingredients protect against Cd nephrotoxicity by reducing oxidative stress, enhancing antioxidant enzyme activity, inhibiting inflammation, preventing apoptosis, alleviating endoplasmic reticulum (ER) stress, enhancing autophagy and improving mitochondrial function in the kidney.

Conclusion

The present study indicates that an extensive understanding of the protective effects of herbal active ingredients holds promise for the development of innovative approaches to safeguard human health and environmental integrity against the detrimental effects of Cd exposure.

THERAPEUTIC USE OF ALPHA-LIPOIC ACID SUPPLEMENTATION: A REVIEW ON CURRENT USE AND FUTURE PROSPECTIVE

Alpha-lipoic acid (ALA, thioctic acid, 5-(1,2-dithiolan-3-yl) pentanoic acid) is an organosulfur compound produced by plants, humans, and animals. ALA plays a crucial role in mitochondrial bioenergetics reactions. It is a natural antioxidant and a dithiol compound. ALA is a coenzyme that plays a crucial role in the function of pyruvate and Alpha-ketoglutarate dehydrogenase complexes found in mitochondria. ALA has cytotoxic and antiproliferative effects on several cancers, including Polycystic Ovarian Syndrome (PCOS). Most of ALA's clinical applications come from its antioxidant properties, but it also shows potential in treating female and male infertility. Although ALA can potentially be a therapeutic agent, its pharmacokinetic profile limits its effectiveness. Research suggests that ALA has a short half-life and low bioavailability (around 30%) because it gets broken down in the liver, has reduced solubility, and is unstable in the stomach. Liquid formulations have higher bioavailability and plasma concentration than solid dose forms. This review covers the current clinical evidence on using ALA to prevent, manage, and cure numerous disorders, including diabetic neuropathy, obesity, central nervous system-related ailments, and pregnancy abnormalities.

The mode of toxic action of ionic liquids: Narrowing down possibilities using high-throughput, in vitro cell-based bioassays

Growing concerns about the environmental impact of ionic liquids (ILs) have spurred research into their (eco)toxic effects, but studies on their mode of toxic action (MOA) still remain limited. However, understanding the MOA and identifying structural features responsible for enhanced toxicity is crucial for characterising the hazard and designing safer alternatives. Therefore, 45 ILs, with systematically varied chemical structures, were tested for cytotoxicity and two specific endpoints in reporter gene assays targeting the Nrf2-ARE mediated oxidative stress response (AREc32) and aryl hydrocarbon receptor activation (AhR-CALUX). While none of the ILs activated the reporter genes, cytotoxicity was high and markedly different between cell lines. Seven and 25 ILs proved more cytotoxic than predicted by baseline toxicity model in the AREc32 and the AhR-CALUX assays, respectively. The length of the side chain and headgroup structures of ILs altered the MOA of ILs. Cellular metabolism of the ILs, investigated by LC-MS/MS, showed side-chain oxidation of the long-chain quaternary ammonium compounds in AhR-CALUX cells and, to a lower extent, in AREc32 cells, however, this transformation could not explain the high cytotoxicity. Effect data for 72 ILs for ten endpoints retrieved from the Tox21 database identified the inhibition of aromatase activity and of mitochondrial membrane potential as potential MOAs. However, in vitro fluorimetric assays for these endpoints demonstrated that effects were activated in a non-specific manner, probably through cytotoxicity. Although many of the ILs tested induced cytotoxicity at concentrations lower than baseline toxicity, the specific MOAs responsible could not be identified. Alternatively, we suggest that the descriptors currently used may fail to define the affinity of ILs for cells. Testing of the affinity of ILs for a diverse range of biomolecules is needed to accurately describe their interactions with cells.

Hepatoprotective potential of alpha-lipoic acid against gliclazide-induced liver injury in high-glucose-exposed human liver cells and experimental type 2 diabetic rats

Growing clinical evidence shows that sulfonylurea therapy for patients with type 2 diabetic mellitus (T2DM) contributes to progressive worsening of their liver. The present study presents hepatotoxicity induced by gliclazide, a second-generation sulfonylurea, and alpha-lipoic acid (ALA) as a novel and promising drug for T2DM treatment. Normal human liver cells (HL-7702) were incubated with high-glucose DMEM in the presence or absence of gliclazide and ALA for 72 h, and cell viability and death were measured by flow cytometry. Next, Sprague-Dawley rats were subjected to 12 h of fasting, and fasting blood glucose was measured. The rats were randomized into four groups: HC (healthy control; n = 7), T2DM (diabetic rats without treatment; n = 9), GLC (diabetic rats with 15 mg/kg gliclazide treatment; n = 7) and GLC+ALA (diabetic rats with gliclazide and 60 mg/kg ALA treatment; n = 7). T2DM was induced by a bolus administration of 110 mg/kg nicotinamide and 55 mg/kg streptozotocin intraperitoneally. The experimental protocol lasted for 6 weeks after which the animals were sacrificed and pancreas, liver and blood samples were collected for biochemical, histological and molecular analyses. Compared to healthy control (HC) group, exposure of HL-7702 cells to high glucose induced significant cell death by 19 % (p < 0.001), which was exacerbated with gliclazide treatment by 29 % (p < 0.0001) but markedly reduced by 6 % to near HC value following ALA treatment. In vivo, GLC-treated rats had severe liver damage characterized by increased hepatocellular vacuolation, and significant expression of ED-1, iNOS and caspase-3 as well as markedly high levels of liver enzymes (aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase compared to T2DM rats. Interestingly, ALA administration prevented these pathological changes and protected the diabetic liver to levels comparable to HC rats. ALA showed hepatoprotective effect against gliclazide-induced hepatotoxicity by suppressing inflammation and apoptosis while activating antioxidant pathway in the diabetic liver. Abbreviations: ALA, Alpha-lipoic acid; ALT, Alanine aminotransferase; ALP, Alkaline phosphatase; AMPK, Adenosine monophosphate-activated protein kinase; AST, Aspartate aminotransferase; ATP, Adenosine triphosphate; DMEM, Dulbecco's Modified Eagle Medium; EDTA, ethylenediaminetetraacetic acid; FBG, Fasting blood glucose; FBS, Fetal bovine serum; GLC, Gliclazide; GLUT4, Glucose transporter type 4; GSH, Glutathione; H&E, Hematoxylin/Eosin; HbA1c, Glycosylated haemoglobin A1c; HC, Healthy control; HG, Hyperglycemic group; HOMA-β, Homeostasis model assessment of β-cell function; IL-1β, Interleukin-1β; IL-6, Interleukin-6; iNOS, Inducible nitric oxide synthase; KATP, ATP-dependent potassium channels; MDA, Malondialdehyde; MPTP, Mitochondrial permeability transition pore; NO, Nitric oxide; P/S, Penicillin/streptomycin; PAS, Periodic acid-Schiff; RIA, Radioimmunoassay; ROS, Reactive oxygen species; SOD, Superoxide dismutase; T2DM, Type 2 diabetes mellitus; TBARS, Thiobarbituric acid reactive substances; TNF-α, Tumor necrosis factor-alpha.

A Multi-Target Pharmacological Correction of a Lipoyltransferase LIPT1 Gene Mutation in Patient-Derived Cellular Models

Mutations in the lipoyltransferase 1 (LIPT1) gene are rare inborn errors of metabolism leading to a fatal condition characterized by lipoylation defects of the 2-ketoacid dehydrogenase complexes causing early-onset seizures, psychomotor retardation, abnormal muscle tone, severe lactic acidosis, and increased urine lactate, ketoglutarate, and 2-oxoacid levels. In this article, we characterized the disease pathophysiology using fibroblasts and induced neurons derived from a patient bearing a compound heterozygous mutation in LIPT1. A Western blot analysis revealed a reduced expression of LIPT1 and absent expression of lipoylated pyruvate dehydrogenase E2 (PDH E2) and alpha-ketoglutarate dehydrogenase E2 (α-KGDH E2) subunits. Accordingly, activities of PDH and α-KGDH were markedly reduced, associated with cell bioenergetics failure, iron accumulation, and lipid peroxidation. In addition, using a pharmacological screening, we identified a cocktail of antioxidants and mitochondrial boosting agents consisting of pantothenate, nicotinamide, vitamin E, thiamine, biotin, and α-lipoic acid, which is capable of rescuing LIPT1 pathophysiology, increasing the LIPT1 expression and lipoylation of mitochondrial proteins, improving cell bioenergetics, and eliminating iron overload and lipid peroxidation. Furthermore, our data suggest that the beneficial effect of the treatment is mainly mediated by SIRT3 activation. In conclusion, we have identified a promising therapeutic approach for correcting LIPT1 mutations.

Curcumin Reduces Depression in Obese Patients with Type 2 Diabetes: A Randomized Controlled Trial

Type 2 diabetes and depression co-occur in a bidirectional manner. Curcumin supplements exhibit antidepressant effects that may mitigate depression by modulating neurotransmitters and reducing inflammatory and oxidative stress pathways. This study aimed to evaluate the efficacy of curcumin in improving depression severity in obese type 2 diabetes patients. The study employed a randomized, double-blind, placebo-controlled trial design with 227 participants. The primary end-point was depression severity assessed using the Patient Health Questionnaire-9. Biomarkers were measured at baseline and at 3-, 6-, 9-, and 12-month intervals. The biomarkers assessed were serotonin levels, pro-inflammatory cytokines (interleukin-1 beta, interleukin-6, tumor necrosis factor-alpha), antioxidant activities (total antioxidant status, glutathione peroxidase, and superoxide dismutase), and malondialdehyde. After 12 months, the curcumin group exhibited significantly improved depression severity (p = 0.000001). The curcumin group had higher levels of serotonin (p < 0.0001) but lower levels of interleukin-1 beta, interleukin-6, and tumor necrosis factor-alpha (p < 0.001 for all) than the placebo group. Total antioxidant status, glutathione peroxidase activity, and superoxide dismutase activity were elevated in the curcumin group, whereas malondialdehyde levels were greater in the placebo group (p < 0.001 for all). These findings suggest curcumin may have antidepressant effects on obese type 2 diabetes patients.

Alpha-lipoic acid alleviates cognitive deficits in transgenic APP23/PS45 mice through a mitophagy-mediated increase in ADAM10 α-secretase cleavage of APP

BACKGROUND

Alpha-lipoic acid (ALA) has a neuroprotective effect on neurodegenerative diseases. In the clinic, ALA can improve cognitive impairments in patients with Alzheimer's disease (AD) and other dementias. Animal studies have confirmed the anti-amyloidosis effect of ALA, but its underlying mechanism remains unclear. In particular, the role of ALA in amyloid-β precursor protein (APP) metabolism has not been fully elucidated.

OBJECTIVE

To investigate whether ALA can reduce the amyloidogenic effect of APP in a transgenic mouse model of AD, and to study the mechanism underlying this effect.

METHODS

ALA was infused into 2-month-old APP23/PS45 transgenic mice for 4 consecutive months and their cognitive function and AD-like pathology were then evaluated. An ALA drug concentration gradient was applied to 20E2 cells in vitro to evaluate its effect on the expression of APP proteolytic enzymes and metabolites. The mechanism by which ALA affects APP processing was studied using GI254023X, an inhibitor of A Disintegrin and Metalloproteinase 10 (ADAM10), as well as the mitochondrial toxic drug carbonyl cyanide m-chlorophenylhydrazone (CCCP).

RESULTS

Administration of ALA ameliorated amyloid plaque neuropathology in the brain tissue of APP23/PS45 mice and reduced learning and memory impairment. ALA also increased the expression of ADAM10 in 20E2 cells and the non-amyloidogenic processing of APP to produce the 83 amino acid C-terminal fragment (C83). In addition to activating autophagy, ALA also significantly promoted mitophagy. BNIP3L-knockdown reduced the mat/pro ratio of ADAM10. By using CCCP, ALA was found to regulate BNIP3L-mediated mitophagy, thereby promoting the α-cleavage of APP.

CONCLUSIONS

The enhanced α-secretase cleavage of APP by ADAM10 is the primary mechanism through which ALA ameliorates the cognitive deficits in APP23/PS45 transgenic mice. BNIP3L-mediated mitophagy contributes to the anti-amyloid properties of ALA by facilitating the maturation of ADAM10. This study provides novel experimental evidence for the treatment of AD with ALA.

Outcomes of dietary alpha-lipoic acid on testicular vascularization, steroid hormones, and seminal quality in aged Baladi bucks

BACKGROUND

Senescence is accompanied by a progressive decrease in male reproductive performance, mainly due to oxidative stress and endothelial dysfunction. Alpha lipoic acid (ALA) is a potent antioxidant, that diffuses freely in aqueous and lipid phases, possessing anti-inflammatory and anti-apoptotic properties. This study aimed to examine the effects of supplemental dietary ALA on testicular hemodynamics (TH), circulating hormones, and semen quality in aged goats. Twelve Baladi bucks were divided into two groups (n = 6 each); the first fed a basic ration and served as a control group (CON), while the second received the basic ration supplemented with 600 mg ALA/ kg daily for consecutive eight weeks (ALA).

RESULTS

There were improvements in testicular blood flow in the ALA group evidenced by a lower resistance index (RI) and pulsatility index (PI) concurrent with higher pampiniform-colored areas/pixel (W3-W6). There were increases in testicular volume and decreases in echogenicity (W3-W5; ALA vs. CON). Compared to the CON, ALA-bucks had higher serum concentrations of testosterone, estradiol, and nitric oxide (W3-W5). There were enhancements in semen traits (progressive motility, viability, morphology, and concentration, alanine aminotransferase enzyme) and oxidative biomarkers (catalase, total antioxidant capacity, and malondialdehyde).

CONCLUSIONS

ALA dietary supplementation (600 mg/kg diet) improved aged bucks' reproductive performance by enhancing the testicular volume, testicular hemodynamics, sex steroids, and semen quality.

Liquid- and Semisolid-Filled Hard Gelatin Capsules Containing Alpha-Lipoic Acid as a Suitable Dosage Form for Compounding Medicines and Dietary Supplements

Liquid-filled hard gelatin capsules may have pertinent advantages both for therapeutic effect and extemporaneous preparations of medicines. Alpha lipoic acid is a substance used in medicines and dietary supplements and there is a need for creating an appropriate formulation which would be suitable for each individual patient or consumer. Based on its biopharmaceutical and physical chemical characteristics, eight different capsule formulations were designed and characterized. Silicon dioxide was added to form a semisolid content and prevent leakage. The formulation filled with alpha lipoic acid solution in polyethylene glycol 400 showed the best performance. Although the addition of silicon dioxide to the formulation with polyethylene glycol 400 led to a change in both flow character and viscosity, the release rate did not show a statistically significant decrease (more than 85% of content was released after 5 min testing). Applied technique is a simple and an appropriate approach for compounding and could be used for other substances with similar properties.

The effectiveness of antioxidant agents in delaying progression of diabetic nephropathy: A systematic review of randomized controlled trials

Introduction

Oxidative stress plays a central role in the pathophysiology of diabetes mellitus and its complications, including diabetic nephropathy. Excessive production of reactive oxygen species (ROS) alters renal metabolic pathways, leading to inflammation, endothelial dysfunction, and fibrosis, ultimately resulting in end-stage renal disease (ESRD). Studies have shown that exogenous antioxidants can improve the pathophysiological condition of patients with diabetic nephropathy. Objective: This systematic review aims to investigate the types of antioxidant agents that inhibit the development of diabetic nephropathy and the effectiveness of antioxidant agent interventions to repair kidney structure and function.

Methods

A systematic review of randomized controlled trials that examined the role of antioxidants in improving diabetic nephropathy was conducted. The literature search was performed on PubMed, ScienceDirect, and EBSCO. The inclusion criteria covered articles on the antioxidant activity of herbal extracts and compounds that inhibit the progression of diabetic nephropathy in humans. In addition, the articles were written in English and published between 2012 and 2022. The reporting of the systematic review followed the Preferred Reporting Elements for Systematic Review and Meta-Analysis (PRISMA) guideline. The full texts of all potentially relevant systematic reviews were assessed for quality using the Risk of Bias 2 (RoB 2) tool.

Results

A total of 2,367 articles were identified in the three databases, of which only 15 articles met the inclusion criteria. Antioxidant agents that inhibit diabetic nephropathy can be classified as single antioxidants (silymarin, baicalin, epigallocatechin gallate, vitamin E, selenium, curcumin, α-lipoic acid, and tocotrienol-rich vitamin E) and combined antioxidants (α-lipoic acid with vitamin B6, and resveratrol with losartan). Antioxidant agents have been shown to reduce oxidative stress and inflammation, but their role in the progression of fibrosis remains unclear. The oxidative stress marker MDA was significantly reduced by silymarin, curcumin, vitamin E, tocotrienol-rich vitamin E, selenium, ALA, vitamin B, resveratrol and losartan. Silymarin was found to be the most effective (-3.43 µmol/L; 6.02 to 0.83). Compared to silymarin and epigallocatechin gallate, vitamin E was more effective (at -35.4 ng/L; P < 0.001) in reducing inflammation by decreasing TNF-α levels. In addition, tocotrienol-rich vitamin E, silymarin, baicalin, and selenium showed a decrease TGF-β levels, but did not show statistically significant differences between the placebo and intervention groups.

Conclusion

Potential antioxidant agents, such as flavonoids, vitamins, fatty acids, and antioxidant minerals, were examined in this systematic review. These agents contribute to reducing markers of oxidative stress and hyperglycemia-induced inflammation. Although several antioxidants play a role in reducing fibrosis markers, the effect does not appear to be statistically significant.

Nanotechnological Approaches to Enhance the Potential of α-Lipoic Acid for Application in the Clinic

α-lipoic acid is a naturally occurring compound with potent antioxidant properties that helps protect cells and tissues from oxidative stress. Its incorporation into nanoplatforms can affect factors like bioavailability, stability, reactivity, and targeted delivery. Nanoformulations of α-lipoic acid can significantly enhance its solubility and absorption, making it more bioavailable. While α-lipoic acid can be prone to degradation in its free form, encapsulation within nanoparticles ensures its stability over time, and its release in a controlled and sustained manner to the targeted tissues and cells. In addition, α-lipoic acid can be combined with other compounds, such as other antioxidants, drugs, or nanomaterials, to create synergistic effects that enhance their overall therapeutic benefits or hinder their potential cytotoxicity. This review outlines the advantages and drawbacks associated with the use of α-lipoic acid, as well as various nanotechnological approaches employed to enhance its therapeutic effectiveness, whether alone or in combination with other bioactive agents. Furthermore, it describes the engineering of α-lipoic acid to produce poly(α-lipoic acid) nanoparticles, which hold promise as an effective drug delivery system.

Mini-encyclopedia of mitochondria-relevant nutraceuticals protecting health in primary and secondary care-clinically relevant 3PM innovation

Despite their subordination in humans, to a great extent, mitochondria maintain their independent status but tightly cooperate with the "host" on protecting the joint life quality and minimizing health risks. Under oxidative stress conditions, healthy mitochondria promptly increase mitophagy level to remove damaged "fellows" rejuvenating the mitochondrial population and sending fragments of mtDNA as SOS signals to all systems in the human body. As long as metabolic pathways are under systemic control and well-concerted together, adaptive mechanisms become triggered increasing systemic protection, activating antioxidant defense and repair machinery. Contextually, all attributes of mitochondrial patho-/physiology are instrumental for predictive medical approach and cost-effective treatments tailored to individualized patient profiles in primary (to protect vulnerable individuals again the health-to-disease transition) and secondary (to protect affected individuals again disease progression) care. Nutraceuticals are naturally occurring bioactive compounds demonstrating health-promoting, illness-preventing, and other health-related benefits. Keeping in mind health-promoting properties of nutraceuticals along with their great therapeutic potential and safety profile, there is a permanently growing demand on the application of mitochondria-relevant nutraceuticals. Application of nutraceuticals is beneficial only if meeting needs at individual level. Therefore, health risk assessment and creation of individualized patient profiles are of pivotal importance followed by adapted nutraceutical sets meeting individual needs. Based on the scientific evidence available for mitochondria-relevant nutraceuticals, this article presents examples of frequent medical conditions, which require protective measures targeted on mitochondria as a holistic approach following advanced concepts of predictive, preventive, and personalized medicine (PPPM/3PM) in primary and secondary care.

Lipoic acid-mediated oral drug delivery system utilizing changes on cell surface thiol expression for the treatment of diabetes and inflammatory diseases

Lipoic acid (LA), which has good safety and oral absorption, is obtained from various plant-based food sources and needs to be supplemented through human diet. Moreover, substances with a disulfide structure can enter cells through dynamic covalent disulfide exchange with thiol groups on the cell membrane surface. Based on these factors, we constructed LA-modified nanoparticles (LA NPs). Our results showed that LA NPs can be internalized into intestinal epithelial cells through surface thiols, followed by intracellular transcytosis via the endoplasmic reticulum-Golgi pathway. Further mechanistic studies indicated that disulfide bonds within the structure of LA play a critical role in this transport process. In a type I diabetes rat model, the oral administration of insulin-loaded LA NPs exhibited a more potent hypoglycemic effect, with a pharmacokinetic bioavailability of 5.42 ± 0.53%, representing a 1.6 fold enhancement compared to unmodified PEG NPs. Furthermore, a significant upregulation of surface thiols in inflammatory macrophages was reported. Thus, we turned our direction to investigate the uptake behavior of inflammatory macrophages with increased surface thiols towards LA NPs. Inflammatory macrophages showed a 2.6 fold increased uptake of LA NPs compared to non-inflammatory macrophages. Surprisingly, we also discovered that the antioxidant resveratrol facilitates the uptake of LA NPs in a concentration-dependent manner. This is mainly attributed to an increase in glutathione, which is involved in thiol uptake. Consequently, we employed LA NPs loaded with resveratrol for the treatment of colitis and observed a significant alleviation of colitis symptoms. These results suggest that leveraging the variations of thiol expression levels on cell surfaces under both healthy and diseased states through an oral drug delivery system mediated by the small-molecule nutrient LA can be employed for the treatment of diabetes and certain inflammatory diseases.

Improving Gene Delivery: Synergy between Alkyl Chain Length and Lipoic Acid for PDMAEMA Hydrophobic Copolymers

In the field of gene delivery, hydrophobic cationic copolymers hold great promise. They exhibit improved performance by effectively protecting genetic material from serum interactions while facilitating interactions with cellular membranes. However, managing cytotoxicity remains a significant challenge, prompting an investigation into suitable hydrophobic components. A particularly encouraging approach involves integrating nutrient components, like lipoic acid, which is known for its antioxidant properties and diverse cellular benefits such as cellular metabolism and growth. In this study, a copolymer library comprising 2-(dimethylamino)ethyl methacrylate (DMAEMA) and lipoic acid methacrylate (LAMA), combined with either n-butyl methacrylate (nBMA), ethyl methacrylate (EMA), or methyl methacrylate (MMA), is synthesized. This enables to probe the impact of lipoic acid incorporation while simultaneously exploring the influence of pendant acyclic alkyl chain length. The inclusion of lipoic acid results in a notable boost in transfection efficiency  while maintaining low cytotoxicity. Interestingly, higher levels of transfection efficiency are achieved in the presence of nBMA, EMA, or MMA. However, a positive correlation between pendant acyclic alkyl chain length and cytotoxicity is observed. Consequently, P(DMAEMA-co-LAMA-co-MMA), emerges as a promising candidate. This is attributed to the optimal combination of low cytotoxic MMA and transfection-boosting LAMA, highlighting the crucial synergy between LAMA and MMA.

Cardioprotective effect of antioxidant combination therapy: A highlight on MitoQ plus alpha-lipoic acid beneficial impact on myocardial ischemia-reperfusion injury in aged rats

Objective

(s): Considering the poor prognosis of ischemic heart disease and the diminished effectiveness of cardioprotective interventions in the elderly, it becomes necessary to investigate the interaction of aging with protection during myocardial ischemia/reperfusion injury (IRI). This study was conducted to assess the impact of mitoquinone (MitoQ) and alpha-lipoic acid (ALA) preconditioning on cardioprotection following IRI in aged rats.

Methods

Fifty aged male Wistar rats (22-24 months old) were divided into five groups including Sham, IR, and treatment groups receiving ALA and/or MitoQ. Treatment groups were received 100 mg/kg/day ALA by oral gavage and/or 10 mg/kg/day MitoQ by intraperitoneal injection for 14 consecutive days. An in vivo model of myocardial IRI was established through ligation of coronary artery for 30 min and it's reopening for 24 h. The left ventricles were removed at the end of reperfusion to assess oxidative stress indicators, mitochondrial function, and expression of mitochondrial dynamic genes. Myocardial infarct size (IS), hemodynamic parameters, and serum lactate dehydrogenase (LDH) level were also measured.

Results

Combination of MitoQ and ALA reduced oxidative stress, LDH level, and IS in aged hearts subjected to IRI. It also enhanced mitochondrial function and upregulated Mfn1, Mfn2, and Foxo1 and downregulated Drp1 and Fis1 gene expression. Co-administration of MitoQ and ALA partially restored IRI-induced hemodynamic changes to normal state. In all measured parameters, the effect of combined treatment was greater than monotherapies.

Conclusion

The combination therapy of MitoQ and ALA demonstrated considerable therapeutic potential in protecting the aging heart against IRI by improving oxidative stress, mitochondrial function, and dynamics in aged rats.

Targeting Metabolic Diseases: The Role of Nutraceuticals in Modulating Oxidative Stress and Inflammation

The escalating prevalence of metabolic and cardiometabolic disorders, often characterized by oxidative stress and chronic inflammation, poses significant health challenges globally. As the traditional therapeutic approaches may sometimes fall short in managing these health conditions, attention is growing toward nutraceuticals worldwide; with compounds being obtained from natural sources with potential therapeutic beneficial effects being shown to potentially support and, in some cases, replace pharmacological treatments, especially for individuals who do not qualify for conventional pharmacological treatments. This review delves into the burgeoning field of nutraceutical-based pharmacological modulation as a promising strategy for attenuating oxidative stress and inflammation in metabolic and cardiometabolic disorders. Drawing from an extensive body of research, the review showcases various nutraceutical agents, such as polyphenols, omega-3 fatty acids, and antioxidants, which exhibit antioxidative and anti-inflammatory properties. All these can be classified as novel nutraceutical-based drugs that are capable of regulating pathways to mitigate oxidative-stress- and inflammation-associated metabolic diseases. By exploring the mechanisms through which nutraceuticals interact with oxidative stress pathways and immune responses, this review highlights their potential to restore redox balance and temper chronic inflammation. Additionally, the challenges and prospects of nutraceutical-based interventions are discussed, encompassing bioavailability enhancement, personalized treatment approaches, and clinical translation. Through a comprehensive analysis of the latest scientific reports, this article underscores the potential of nutraceutical-based pharmacological treatment modulation as a novel avenue to fight oxidative stress and inflammation in the complex landscape of metabolic disorders, particularly accentuating their impact on cardiovascular health.

The Association of High-Molecular-Weight Hyaluronic Acid (HMWHA), Alpha Lipoic Acid (ALA), Magnesium, Vitamin B6, and Vitamin D Improves Subchorionic Hematoma Resorption in Women with Threatened Miscarriage: A Pilot Clinical Study

Background-We evaluated whether the oral intake of high-molecular-weight hyaluronic acid (HMWHA) in association with alpha lipoic acid (ALA), magnesium, vitamin B6, and vitamin D can improve the resorption of subchorionic hematoma in cases of threatened miscarriage. Methods-In this study, we enrolled 56 pregnant women with threatened miscarriage (i.e., subchorionic hematomas, pelvic pain/uterine contractions, and/or vaginal bleeding) between the 6th and the 13th week of gestation. They were treated with vaginal progesterone (200 mg/twice a day) (control group; n = 25) or vaginal progesterone plus oral 200 mg HMWHA, 100 mg ALA, 450 mg magnesium, 2.6 mg vitamin B6, and 50 mcg vitamin D (treatment group; n = 31; DAV®-HA, LoLi Pharma srl, Rome, Italy). An ultrasound scan was performed at the first visit (T0) and after 7 days (T1) and 14 days (T2) until hematoma resorption. Results-At the ultrasound scan, the treatment group showed faster resorption of the subchorionic hematoma compared with the control group, both at T1 (control group 140 (112-180), treated group 84 (40-112), p < 0.0031), and T2 (control group: 72 (48-112), treated group: 0 (0-0), p < 0.0001). Moreover, subjective symptoms, such as vaginal bleeding, abdominal pain, and uterine contractions, showed a faster decrease in the treatment group than in the control group. Conclusions-The association may more rapidly improve the resolution of threatened miscarriage and related symptoms compared to the standard local protocol.

Radical Scavenging, Hemocompatibility, and Antibacterial Activity against MDR Acinetobacter baumannii in Alginate-Based Aerogels Containing Lipoic Acid-Capped Silver Nanoparticles

Retaining the hemocompatibility, supporting cell growth, and exhibiting anti-inflammatory and antioxidant properties, while having antimicrobial activity, particularly against multidrug-resistant bacteria (MDR), remain a challenge when designing aerogels for biomedical applications. Here, we report that our synthesized alginate-based aerogels containing either 7.5 or 11.25 μg of lipoic acid-capped silver nanoparticles (AgNPs) showed improved hemocompatibility properties while retaining their antimicrobial effect against MDR Acinetobacter baumannii and the reference strain Escherichia coli, relative to a commercial dressing and polymyxin B, used as a reference. The differences in terms of the microstructure and nature of the silver, used as the bioactive agent, between our synthesized aerogels and the commercial dressing used as a reference allowed us to improve several biological properties in our aerogels with respect to the reference commercial material. Our aerogels showed significantly higher antioxidant capacity, in terms of nmol of Trolox equivalent antioxidant capacity per mg of aerogel, than the commercial dressing. All our synthesized aerogels showed anti-inflammatory activity, expressed as nmol of indomethacin equivalent anti-inflammatory activity per mg of aerogel, while this property was not found in the commercial dressing material. Finally, our aerogels were highly hemocompatible (less than 1% hemolysis ratio); however, the commercial material showed a 20% hemolysis rate. Therefore, our alginate-based aerogels with lipoic acid-capped AgNPs hold promise for biomedical applications.

Antioxidant dihydrolipolic acid protects against in vitro aluminum-induced toxicity

Dihydrolipoic acid (DHLA) is a natural antioxidant known for its ability to counteract metal toxicity and oxidative stress. It has shown the potential to safeguard cells from harmful environmental substances. It may hold therapeutic benefits in treating neurodegenerative disorders by defending against oxidative damage and chronic inflammation. Thus, this study aimed to explore the potential neuroprotective effects of DHLA against aluminum (Al)-induced toxicity using an Alzheimer's disease (AD) model in vitro. The study focused on two important pathways: GSK-3β and the Wnt signaling pathways. The SH-SY5Y cell line was differentiated to establish AD, and the study group were as follows: control, Al, DHLA, Al-DHLA, AD, AD-Al, AD-DHLA, and AD-Al-DHLA. The impact of DHLA on parameters related to oxidative stress was assessed. The activity of the GSK-3β pathway was measured by evaluating the levels of PPP1CA, PP2A, GSK-3β, and Akt. The Wnt signaling pathway was assessed by measuring Wnt/β-catenin in the different study groups. Exposure to DHLA significantly reduced oxidative stress by effectively decreasing the levels of reactive oxygen species, thereby protecting against protein oxidation and limiting the production of malonaldehyde. Moreover, the DHLA-treated groups exhibited a remarkable increase in the total antioxidant capacity. Furthermore, the study observed an upregulation of the Wnt signaling pathway and a downregulation of the GSK-3β pathway in the groups treated with DHLA. In summary, the neuroprotective effects of DHLA, primarily achieved by reducing oxidative stress and modulating critical imbalanced pathways associated with AD, indicate its potential as a promising addition to the treatment regimens of AD patients.

The energetic and physical concept of gold nanorod-dependent fluorescence in cancer treatment and development of new photonic compounds|review

The optical features of gold nanorods (GNR) may be precisely controlled by manipulating their size, shape, and aspect ratio. This review explores the impact of these parameters on the optical tuning of (GNR). By altering the experimental conditions, like the addition of silver ions during the seed-mediated growth process, the aspect ratio of (GNR) may be regulated. The shape is trans from spherical to rod-like structures resulting in noticeable changes in the nanoparticles surface plasmons resonance (SPR) bands. The longitudinal SPR band, associated with electron oscillations along the long axis, exhibits a pronounced red shift into the (NIR) region as the aspect ratio increases. In contrast, the transverse SPR band remains relate unchanged. Using computational methods like the discrete dipole approximation (DDA) allows for analyzing absorption, scattering, and total extinction features of gold (G) nanoparticles. Studies have shown that increasing the aspect ratio enhances the scattering efficiency, indicating a higher scattering quantum yield (QY). These findings highlight the importance of size, shape, and aspect ratio in controlling the optical features of (GNR) providing valuable insights for various uses in nanophotonics and plasmonic-dependent fluorescence in cancer treatment and developing new photonic compound NRs.

Effect of Tea Polyphenols, α-Lipoic Acid and Their Joint Use on the Antioxidant and Lipid Metabolism Performance of Hybrid Grouper (♀Epinephelus fuscoguttatus × ♂E. lanceolatu) Fed with High-Lipid Diets

This study investigated tea polyphenols (TP), α-lipoic acid (ALA) and their joint use on the antioxidant and lipid metabolic performance of hybrid grouper (♀Epinephelus fuscoguttatus × ♂E. lanceolatu) took food with high-fat diets. Six high-lipid diets with isonitrogen (50% of dry matter) and isolipid (17% of dry value) were designed, in which a total content of 1,000 mg/kg additives were added to each group except for the control group (FL). The additives addition ratios in each group were ALA (AL), TP (PL), ALA : TP = 1 : 1 (EL), ALA : TP = 1 : 2 (OL), ALA : TP = 2 : 1 (TL). Each diet was divided into three repeat groups with 30 tails (6.84 ± 0.01 g) in each group and fed for 8 weeks. The consequences were as follows: (1) the highest weight gain rate, specific growth rate, as well as the lowest feed conversion ratio and ingestion rate were discovered in the OL team, which were opposite to the TL group. (2) The body fat content and muscle fat content in the fish oil group were the lowest (P < 0.05), while those of the TL group were the highest. (3) Serum catalase, glutathione peroxidase, total antioxidant capacity, and superoxide dismutase activities were the highest, and the content of reactive oxygen species was the lowest in the OL group. (4) The OL group has the highest hepatic lipase activity and the lowest very low-density lipoprotein content of the liver. In contrast, the TL group had the highest fatty acid synthetase (FAS) activity (P < 0.05). (5) The oil-red aspects of liver tissue displayed lipid particles in other groups were reduced to different degrees compared with FL group, and the OL group showed the best lipid-lowering effect. (6) Compared with the FL group, the relative expressions of FAS, acetyl-CoA carboxylase (acc), and apolipoprotein b-100 (apoB100) genes in the liver were decreased. The relative expressions of lipoprotein lipase (lpl) and peroxisome proliferators-activated receptors-α (pparα) genes related to lipid catabolism were increased, among which the OL group had the most significant change (P < 0.05). (7) According to the 7-day challenge test of Vibrio alginolyticus, the OL group had the highest survival rate. To sum up, both ALA and TP have positive effects on relieving the lipid metabolism disorder of hybrid grouper. If they are jointly used, adding ALA : TP in a ratio of 1 : 2 (OL) may have the best effect, and an addition ratio of 2 : 1 (TL) may inhibit the hybrid grouper growth and increase the feeding cost.

Alpha-lipoic acid induced apoptosis of PC3 prostate cancer cells through an alteration on mitochondrial membrane depolarization and MMP-9 mRNA expression

Cancer has become an important cause of mortality and morbidity in the world. Over the past decades, biomedical research revealed insights into the molecular events and signaling pathways involved in carcinogenesis and cancer progression. Matrix metalloproteinases (MMPs) are a diverse family of enzymes that can degrade various components of the extracellular matrix and are considered as potential diagnostic and prognostic biomarkers for many cancer types and cancer stages. Recently, studies on the role of natural-origin active substances in the prevention of cancer development gained importance. Among them, the α-lipoic acid, which is commonly found in plants, displayed potent anti-proliferative effects on cancer cell lines. However, the effect of the compound on the induction of apoptosis and mRNA expression of MMPs in human prostate cancer cells remains unclear. The present study aimed to evaluate the anti-proliferative and apoptotic activity of α-lipoic acid in human PC3 prostate carcinoma cells considering different concentrations and exposure durations. The findings showed that, α-lipoic acid significantly decreased PC3 cell viability with an IC₅₀ value of 1.71 mM at 48 h (p < 0.05). Additionally, the compound significantly increased Annexin-V binding in cells compared to control and induced a significant alteration in mitochondrial membrane potential and caspase levels (p < 0.05). Furhermore, the RT-PCR analyses have revealed that α-lipoic acid reduced MMP-9 mRNA expression in PC3 cells compared to the control (p < 0.05). In conclusion, this study highlights that α-lipoic acid induced apoptosis in human PC3 prostate cancer cells and inhibited the MMP-9 gene at the mRNA level, which is known to play a role in metastasis development.

The Effect of Alpha-Lipoic Acid in the Treatment of Chronic Subjective Tinnitus through the Tinnitus Handicap Inventory Scores

BACKGROUND AND OBJECTIVES

Tinnitus affects millions of adults. Many therapies, including complementary and alternative medicine and tinnitus retraining therapies, have been trialed, but an effective option, particularly for chronic subjective tinnitus (CTS), is still lacking.

MATERIALS AND METHODS

This study investigated the effects of alpha-lipoic acid (600 mg. per day for two months) on two groups of patients using a questionnaire. One group (A) was affected by tinnitus associated with likely cochlear dysfunction and metabolic syndrome, and the other (B) was composed of subjects with acoustic nerve lesions. All the patients were asked to complete the Italian version of the tinnitus handicap inventory (THI) to determine the overall degree of perceived annoyance at the beginning and end of therapy. Pure tone averages for speech frequencies and for high frequencies were computed, and psychoacoustic pitch and loudness matches were determined for each subject before and after treatment.

RESULTS

The pure tone audiometry, pitch, loudness, and THI scores of both groups were reported. In group A, statistically significant differences were observed for the "functional" and "emotional" subscales. The total score of THI and the loudness of tinnitus were also significantly reduced. No statistically significant differences were observed in group B.

CONCLUSIONS

These findings suggest a possible contribution of the antioxidant effect to the organ of Corti in subjects with metabolic syndrome and CST.

Neuroprotective Efficacy of a Nanomicellar Complex of Carnosine and Lipoic Acid in a Rat Model of Rotenone-Induced Parkinson's Disease

Oxidative stress, accompanied by mitochondrial dysfunction, is a key mechanism involved in the pathogenesis of Parkinson's disease (PD). Both carnosine and lipoic acid are potent antioxidants, the applicability of which in therapy is hindered by their limited bioavailability. This study aimed to evaluate the neuroprotective properties of a nanomicellar complex of carnosine and lipoic acid (CLA) in a rotenone-induced rat model of PD. Parkinsonism was induced via the administration of 2 mg/kg rotenone over the course of 18 days. Two doses of intraperitoneal CLA (25 mg/kg and 50 mg/kg) were administered alongside rotenone to assess its neuroprotective effect. At 25 mg/kg CLA decreased muscle rigidity and partially restored locomotor activity in animals that received rotenone. Furthermore, it caused an overall increase in brain tissue antioxidant activity, accompanied by a 19% increase in neuron density in the substantia nigra and increased dopamine levels in the striatum relative to animals that only received rotenone. Based on the acquired results, it may be concluded that CLA have neuroprotective properties and could potentially be beneficial in PD treatment when used in conjunction with the base therapy.

Dietary Strategies for Relieving Stress in Pet Dogs and Cats

A variety of physical, emotional, and mental factors can induce a stress response in pet dogs and cats. During this process, hypothalamus-pituitary-adrenal (HPA) and sympathetic-adrenal medulla (SAM) axes are activated to produce a series of adaptive short-term reactions to the aversive situations. Meanwhile, oxidative stress is induced where there is an imbalance between the production and scavenging of reactive oxygen species (ROS). Oxidative damage is also incorporated in sustained stress response causing a series of chronic problems, such as cardiovascular and gastrointestinal diseases, immune dysfunction, and development of abnormal behaviors. In this review, the effects and mechanisms of dietary regulation strategies (e.g., antioxidants, anxiolytic agents, and probiotics) on relieving stress in pet dogs and cats are summarized and discussed. We aim to shed light on future studies in the field of pet food and nutrition.

Alpha lipoic acid-loaded electrospun fibrous patch films protect heart in acute myocardial infarction mice by inhibiting oxidative stress

Oxidative stress, characterized by excessive accumulation of reactive oxygen species (ROS), is involved in acute myocardial infarction (AMI)-related pathological processes and vascular reperfusion therapy injury. Alpha lipoic acid (LA) exhibits excellent antioxidant properties, however, its application is limited by inherent characteristics, including rapid clearance and extensive volume distribution. In this study, we hypothesized that scavenging cardiac ROS using adequately delivered LA could promote heart repair. Here, we report a new strategy for dynamic-release LA to treat AMI disease. In particular, this involves using poly(lactic-co-glycolic) (PLGA) copolymers as carriers to form a thin film (LA@PLGA) via electrospinning technology to achieve controlled release of LA, which essentially blocking local ROS production in damaged hearts. The drug-loading capacity and capsulation efficiency of this compound film could be regulated by determining the dose proportions of LA and PLGA. The incubation of LA@PLGA showed strong anti-oxidative activity and anti-apoptosis effect in hydrogen peroxide-administered primary cardiomyocytes. Patching LA@PLGA on the infarcted cardiac surfaces of AMI mice dramatically improved heart functions and reduced cardiac fibrosis throughout ventricular remodeling process. Importantly, the attenuation of detrimental pathologies was observed, including oxidative stress, senescence, DNA damage, cytokine-related processes, apoptosis, and ferroptosis. These results suggest that PLGA-carried LA can reduce ROS damage and restore heart function after myocardial damage, demonstrating a great potential for LA drugs in treating AMI disease.

The Rationale for Vitamin, Mineral, and Cofactor Treatment in the Precision Medical Care of Autism Spectrum Disorder

Children with autism spectrum disorder may exhibit nutritional deficiencies due to reduced intake, genetic variants, autoantibodies interfering with vitamin transport, and the accumulation of toxic compounds that consume vitamins. Importantly, vitamins and metal ions are essential for several metabolic pathways and for neurotransmitter functioning. The therapeutic benefits of supplementing vitamins, minerals (Zinc, Magnesium, Molybdenum, and Selenium), and other cofactors (coenzyme Q10, alpha-lipoic acid, and tetrahydrobiopterin) are mediated through their cofactor as well as non-cofactor functions. Interestingly, some vitamins can be safely administered at levels far above the dose typically used to correct the deficiency and exert effects beyond their functional role as enzyme cofactors. Moreover, the interrelationships between these nutrients can be leveraged to obtain synergistic effects using combinations. The present review discusses the current evidence for using vitamins, minerals, and cofactors in autism spectrum disorder, the rationale behind their use, and the prospects for future use.

Neuroprotective Effect of α-Lipoic Acid against Aβ25-35-Induced Damage in BV2 Cells

The prevalence of Alzheimer's disease (AD) is significantly increasing due to the aging world population, and the currently available drug treatments cannot cure or even slow its progression. α-lipoic acid (LA) is a biological factor widely found in spinach and meat and can dissolve in both lipid and aqueous phases. In medicine, LA has been shown to reduce the symptoms of diabetic polyneuropathy, acute kidney injury, cancers, and some metabolism-related diseases. This study to proves that α-lipoic acid (LA) can stabilize the cognitive function of patients with Alzheimer's disease (AD). BV2 cells were divided into control, LA, Aβ_25-35, and LA + Aβ_25-35 groups. Cell growth; IL-6, IL-1β, TNF-α, IFN-γ, SOD, GPx, CAT, ROS, NO, and iNOS secretion; Wnt-related proteins; cell apoptosis; and cell activation were examined. Here, we found that LA could effectively repress apoptosis and changes in the morphology of microglia BV2 cells activated by Aβ_25-35, accompanied by the inhibition of the inflammatory response induced by Aβ_25-35. The Wnt/β-catenin pathway is also involved in preventing Aβ_25-35-induced cytotoxicity in microglia by LA. We found an inhibitory effect of LA on microglia toxicity induced by Aβ_25-35, suggesting that a combination of anti-inflammatory and antioxidant substances may offer a promising approach to the treatment of AD.

Lipoic/Capsaicin-Related Amides: Synthesis and Biological Characterization of New TRPV1 Agonists Endowed with Protective Properties against Oxidative Stress

α-Lipoic acid is a sulfur-containing nutrient endowed with pleiotropic actions and a safe biological profile selected to replace the unsaturated alkyl acid of capsaicin with the aim of obtaining lipoic amides potentially active as a TRPV1 ligand and with significant antioxidant properties. Thus, nine compounds were obtained in good yields following a simple synthetic procedure and tested for their functional TRPV1 activity and radical-scavenger activity. The safe biological profile together with the protective effect against hypoxia damage as well as the in vitro antioxidant properties were also evaluated. Although less potent than capsaicin, almost all lipoic amides were found to be TRPV1 agonists and, specifically, compound 4, the lipoic analogue of capsaicin, proved to be the best ligand in terms of efficacy and potency. EPR experiments and in vitro biological assays suggested the potential protective role against oxidative stress of the tested compounds and their safe biological profile. Compounds 4, 5 and 9 significantly ameliorated the mitochondrial membrane potential caused by hypoxia condition and decreased F2-isoprostanes, known markers of oxidative stress. Thus, the experimental results encourage further investigation of the therapeutic potential of these lipoic amides.

Effect of add-on alpha lipoic acid on psychopathology in patients with treatment-resistant schizophrenia: a pilot randomized double-blind placebo-controlled trial

RATIONALE

Alpha lipoic acid is known to reverse NMDA receptor hypofunction in addition to dopamine receptor blockade activity. It also enhances neurotrophic factors and has antioxidant potential. These properties combined together may be beneficial for treatment-resistant schizophrenia (TRS).

OBJECTIVES

This study evaluates the effect of alpha lipoic acid (ALA) on psychopathological scores (positive, negative, cognitive), neurotrophic factors and oxidative stress in TRS.

METHODS

A pilot randomized double-blind placebo-controlled parallel design trial was conducted in 20 patients with TRS. After initial screening, participants were randomized into test (add-on ALA) and control (add-on placebo) groups. After recruitment, clinical evaluations with scale for assessment of positive symptoms and negative symptoms (SAPS and SANS), schizophrenia cognitive rating scale (SCoRS), UKU side effect rating scale were done. Serum levels of BDNF, MDA, and GSH were estimated. Patients were followed up for 8 weeks, and clinical and biochemical evaluations were repeated. Adherence to medication was evaluated at follow-up.

RESULTS

A significantly greater improvement was found in SANS score in the test group when compared to control (Mann-Whitney U = 17.0; p = 0.021), whereas there was no significant improvement in SAPS score (Mann-Whitney U = 41.5; p = 0.780). A significant increase in BDNF levels was observed in the control group when compared to ALA (U = 20.0; p = 0.041). No significant differences were found between the test and control groups in serum MDA (U = 30.0; p = 0.221), serum GSH (U = 40.0; p = 0.683), and medication adherence rating scale (MARS) scores (U = 44.0; p = 0.934).

CONCLUSIONS

ALA supplementation improved psychopathology and decreased oxidative stress in patients with TRS. This study thus shows the potential of adjunctive ALA in TRS.

TRIAL REGISTRATION

The study was prospectively registered in Clinical Trial Registry of India (CTRI/2020/03/023707 dated 02.03.2020).

Isolipoic acid-linked gold nanoparticles bearing the thomsen friedenreich tumor-associated carbohydrate antigen: Stability and in vitro studies

We have previously prepared gold nanoparticles (AuNPs) bearing the Thomsen-Friedenreich antigen disaccharide (TF_ag), a pan-carcinoma, Tumor-Associated Carbohydrate Antigen (TACA), as tools for various assays and biological applications. Conjugation to AuNPs typically involves the use of thiols due to the affinity of sulfur for the gold surface of the nanoparticle. While a use of a single thiol-containing ligand bound to the gold surface is standard practice, several studies have shown that ligands bearing multiple thiols can enhance the strength of the conjugation in a nearly linear fashion. (R)-(+)-α-Lipoic acid (LA), a naturally occurring disulfide-containing organic acid that is used as a cofactor in many enzymatic reactions, has been used as a linker to conjugate various molecules to AuNPs through its branched di-thiol system to enhance nanoparticle stability. We sought to use a similar system to increase nanoparticle stability that was devoid of the chiral center in (R)-(+)-α-lipoic acid. Isolipoic acid, an isomer of LA, where the exocyclic pentanoic acid chain is shifted by one carbon on the dithiolane ring to produce an achiral acid, was thought to act similarly as LA without the risk of any contaminating (L)-(−) isomer. We synthesized AuNPs with ligands of both serine and threonine glycoamino acids bearing the TF_ag linked to isolipoic acid and examined their stability under various conditions. In addition, these particles were shown to bind to Galectin-3 and inhibit the interaction of Galectin-3 with a protein displaying copies of the TF_ag. These agents should prove useful in the design of potential antimetastatic therapeutics that would benefit from achiral linkers that are geometrically linear and achiral.

Effects of the Topical Use of the Natural Antioxidant Alpha-Lipoic Acid on the Ocular Surface of Diabetic Patients with Dry Eye Symptoms

PURPOSE

The purpose of this study is to investigate the effects of the treatment with eye-drops based on a combination of antioxidant and mucomimetic molecules, namely 0.1% alpha-lipoic acid (ALA) and 0.3% hydroxy-propyl-methylcellulose (HPMC) on the ocular surface of diabetic patients with dry eye symptoms.

METHODS

Seventy patients, 42 M and 28 F, aged from 50 to79 years (mean 62.1 ± 10.5), affected by type II diabetes mellitus, were enrolled and divided in two groups treated for 2 months as follows: Group 1 (35 patients), received topical ALA/HPMC three times a day, Group 2 (35 patients) received topical HPMC (0.3%) alone, three times a day. The main outcome measures were: Ocular Surface Disease Index (OSDI), tear film break-up time (TBUT), corneal fluorescein staining, Schirmer I test, corneal sensitivity. An examination of tear film morphology with confocal microscopy was carried out in a subset of patients of each group at baseline and after two months. Statistical analysis was performed with t-test for the parametric data and Mann-Whitney U-test or chi-squared test for the nonparametric data.

RESULTS

Both treatments resulted in significant improvements of BUT, OSDI and tear film morphology, although the improvements observed in group 1 showed a higher trend than what observed for group 2. Moreover, only in group 1 a significant improvement was visible for corneal staining, and no significant improvements were observed in any group for Schirmer I and sensitivity.

CONCLUSIONS

These results confirmed the efficacy of HPMC in the treatment of diabetic dry eye and indicated that the addition of a strong self-regenerating antioxidant like ALA may give a distinctive advantage for the healing of corneal defects (as evidenced by corneal staining), beside improving HPMC efficacy on three other parameters (BUT, OSDI score, tear morphology). Therefore, the addition of a strong antioxidant like ALA can be helpful in preventing or treating ocular surface defects in diabetic patients, in which the oxidative damage is predominant.

α-Lipoic Acid, an Organosulfur Biomolecule a Novel Therapeutic Agent for Neurodegenerative Disorders: An Mechanistic Perspective

Lipoic acid (α-LA) (1,2-dithiolane3-pentanoic acid (C₈H₁₄O₂S₂) is also called thioctic acid with an oxidized (disulfide, LA) and a reduced (di-thiol: dihydro-lipoic acid, DHLA) form of LA. α-LA is a potent anti-oxidative agent that has a significant potential to treat neurodegenerative disorders. α-LA is both hydrophilic and hydrophobic in nature. It is widely distributed in plants and animals in cellular membranes and in the cytosol, which is responsible for LA's action in both the cytosol and plasma membrane. A systematic literature review of Bentham, Scopus, PubMed, Medline, and EMBASE (Elsevier) databases was carried out to understand the Nature and mechanistic interventions of the α-Lipoic acid for central nervous system diseases. Moreover, α-LA readily crosses the blood-brain barrier, which is a significant factor for CNS activities. The mechanisms of α-LA reduction are highly tissue-specific. α-LA produces its neuroprotective effect by inhibiting reactive oxygen species formation and neuronal damage, modulating protein levels, and promoting neurotransmitters and anti-oxidant levels. Hence, the execution of α-LA as a therapeutic ingredient in the therapy of neurodegenerative disorders is promising. Finally, based on evidence, it can be concluded that α-LA can prevent diseases related to the nervous system.

Encapsulation of Alpha-Lipoic Acid in Functional Hybrid Liposomes: Promising Tool for the Reduction of Cisplatin-Induced Ototoxicity

In this study, in order to address the drawback of cisplatin (CDDP)-induced ototoxicity, we propose a straightforward strategy based on the delivery of a sulfur-based antioxidant, such as lipoic acid (LA), to HEI-OC1 cells. To this aim, hybrid liposomes (LA@PCGC) with a spherical shape and a mean diameter of 25 nm were obtained by direct sonication of LA, phosphatidylcholine and a gelatin-curcumin conjugate in a physiological buffer. LA@PCGC were found to be stable over time, were quickly (i.e., by 1 h) taken up by HEI-OC1 cells, and guaranteed strong retention of the bioactive molecule, since LA release was less than 20%, even after 100 h. Cell viability studies showed the efficiency of LA@PCGC for stabilizing the protective activity of LA. Curcumin residues within the functional liposomes were indeed able to maintain the biological activity of LA, significantly improving (up to 2.19-fold) the viability of HEI-OC1 cells treated with 5 μM CDDP. Finally, LA@PCGC was incorporated within an alginate-based injectable hydrogel carrier to create a formulation with physical chemical features suitable for potential ear applications.

Effects of alpha lipoic acid on metabolic syndrome: A comprehensive review

Metabolic syndrome (MetS) is a multifactorial disease with medical conditions such as hypertension, diabetes, obesity, dyslipidemia, and insulin resistance. Alpha-lipoic acid (α-LA) possesses various pharmacological effects, including antidiabetic, antiobesity, hypotensive, and hypolipidemia actions. It exhibits reactive oxygen species scavenger properties against oxidation and age-related inflammation and refines MetS components. Also, α-LA activates the 5' adenosine monophosphate-activated protein kinase and inhibits the NFκb. It can decrease cholesterol biosynthesis, fatty acid β-oxidation, and vascular stiffness. α-LA decreases lipogenesis, cholesterol biosynthesis, low-density lipoprotein and very low-density lipoprotein levels, and atherosclerosis. Moreover, α-LA increases insulin secretion, glucose transport, and insulin sensitivity. These changes occur via PI3K/Akt activation. On the other hand, α-LA treats central obesity by increasing adiponectin levels and mitochondrial biogenesis and can reduce food intake mainly by SIRT1 stimulation. In this review, the most relevant articles have been discussed to determine the effects of α-LA on different components of MetS with a special focus on different molecular mechanisms behind these effects. This review exhibits the potential properties of α-LA in managing MetS; however, high-quality studies are needed to confirm the clinical efficacy of α-LA.