Effect of alpha-lipoic acid on arterial stiffness parameters in type 2 diabetes mellitus patients with cardiac autonomic neuropathy

Endothelial dysfunction in patients with different obesity phenotypes

Background. Obesity is a progressive problem in society. The degree of cardiovascular risk in obesity depends on the distribution of adipose tissue, as well as on the endothelial function, since it is endothelial dysfunction that is one of the first links in triggering the development of cardiovascular diseases. The purpose of the study was to determine the functional state of the endothelium in patients with different obesity phenotypes. Materials and methods. During 2019–2021, 88 people were exa­mined: 25 men, 63 women. Their average age was 37.42 ± 11.77 years. A history was collected from all patients in order to determine risk factors for cardiovascular pathology. The blood levels of adipocytokines (leptin and adiponectin) and proinflammatory cytokines (interleukin (ІL) 6, ІL-8, ІL-17) were evaluated using the AU480 biochemical analyzer (Beckman Coulter, Inc., USA). Statistical processing of the results was carried out with the help of the Statistica 7 package (StatSoft, USA). Results. The study had demonstrated that leptin levels in all obesity phenotypes were higher than the reference values of the reagent sets. Consequently, adiponectin level with the progression of visceral obesity was as close as possible to the lower indicators of reference norms. It was found that ІL-17 is an interleukin that triggered an inflammatory reaction in all examined patients. ІL-17 stimulated the activity of pro-inflammatory cytokines ІL-8, ІL-6. The highest cytokine activity was recorded in the presence of visceral obesity without metabolic disorders (phenotype III): ІL-6 was 3.28 ± 1.52 pg/ml, ІL-8 was 96.55 ± 20.30 pg/ml. Due to the activation of the inflammatory reaction, NO synthase is secreted in a state of functional tension, therefore, its level is higher in phenotypes III and IV. Over time, its activity is expected to drop sharply, which will provoke endothelial remodeling. Conclusions. Patients with different phenotypes have a predisposition to endothelial dysfunction. Visceral obesity is the main predictor of the further development of insulin resistance, cardiometabolic disorders, as evidenced by an increase in the level of NO synthase, ІL-17, ІL-8, leptin.

A novel approach to alpha-lipoic acid therapy in the treatment of diabetic peripheral neuropathy

Diabetic peripheral neuropathy (DPN) is a heterogenic disorder prevalent amongst patients suffering from diabetes mellitus (DM), with symptoms comprising neuropathic pain, paresthesia, and numbness in distal lower limbs. Alpha-lipoic acid (ALA) is proposed as a pathogenesis-oriented treatment option, targeting underlying causes of neural lesions such as hyperglycemia, metabolic and microvascular dysfunctions, and cellular oxidative stress. We performed a comprehensive review of controlled clinical trials demonstrating the clinical usefulness of ALA in the treatment of DPN, published in the last 5 years to determine the benefits of ALA monotherapy and combined treatments with other known antioxidants. We also investigated the differential efficacy of oral versus intravenous ALA administration. Clinical trials show the efficacy of ALA treatment, attributed to its anti-inflammatory, anti-hyperglycemic, and antioxidant properties, as well as its function in the endothelial activation and lipid metabolism parameters. ALA supplementation is associated with amelioration in nerve conduction velocity scores, clinically significant reduction of reported neuropathic pain, burning and paresthesia, as well as a decrease in serum triglycerides, improved insulin sensitivity, and quality of life.

Evaluation of the protective roles of alpha-lipoic acid supplementation on nanomaterial-induced toxicity: A meta-analysis of in vitro and in vivo studies

Extensive exposure to nanomaterials causes oxidative stress and inflammation in various organs and leads to an increased risk of adverse health outcomes; therefore, how to prevent the toxic effects are of great concern to human. Alpha-lipoic acid (ALA) has anti-oxidant and anti-inflammatory activities, suggesting it may be effective to prevent nanomaterial-induced toxicity. However, the results obtained in individual studies remained controversial. We aimed to comprehensively evaluate the effects of ALA supplementation on nanomaterial-induced toxicity by performing a meta-analysis. Databases of PubMed, EMBASE, and Cochrane Library were searched up to May 2022. STATA 15.0 software was used for statistical analysis. Twelve studies were included. Meta-analysis of eight in vivo studies showed ALA supplementation could exert significant effects on nanomaterial-induced oxidative stress (by reducing MDA, ROS and increasing GSH, CAT, GPx, and SOD), inflammation (by downregulating NO, IgG, TNF-α, IL-6, and CRP), apoptosis (by activation of pro-apoptotic caspase-3), DNA damage (by a reduction in the tail length) and organ damage (by a decrease in the liver biomarker ALT and increases in brain neuron biomarker AChE and heart biomarker CPK). Pooled analysis of four in vitro studies indicated ALA intervention increased cell viability, decreased ROS levels, inhibited cell apoptosis and chelated metal ions. Subgroup analyses revealed changing the levels of GSH, IL-6, and metal ions were the main protective mechanisms of ALA supplementation because they were not changed by any subgroup factors. In conclusion, ALA supplementation may represent a potential strategy for the prevention of the toxicity induced by nanomaterials.