Injuries of the central (CNS) and peripheral nervous system (PNS) are a serious problem of the modern healthcare system. The situation is complicated by the lack of clinically effective neuroprotective drugs that can protect damaged neurons and glial cells from death. In addition, people who have undergone neurotrauma often develop mental disorders and neurodegenerative diseases that worsen the quality of life up to severe disability and death. Hydrogen sulfide (H₂S) is a gaseous signaling molecule that performs various cellular functions in normal and pathological conditions. However, the role of H₂S in neurotrauma and mental disorders remains unexplored and sometimes controversial. In this large-scale review study, we examined the various biological effects of H₂S associated with survival and cell death in trauma to the brain, spinal cord, and PNS, and the signaling mechanisms underlying the pathogenesis of mental illnesses, such as cognitive impairment, encephalopathy, depression and anxiety disorders, epilepsy and chronic pain. We also studied the role of H₂S in the pathogenesis of neurodegenerative diseases: Alzheimer’s disease (AD) and Parkinson’s disease (PD). In addition, we reviewed the current state of the art study of H₂S donors as neuroprotectors and the possibility of their therapeutic uses in medicine. Our study showed that H₂S has great neuroprotective potential. H₂S reduces oxidative stress, lipid peroxidation, and neuroinflammation; inhibits processes associated with apoptosis, autophagy, ferroptosis and pyroptosis; prevents the destruction of the blood-brain barrier; increases the expression of neurotrophic factors; and models the activity of Ca²⁺ channels in neurotrauma. In addition, H₂S activates neuroprotective signaling pathways in psychiatric and neurodegenerative diseases. However, high levels of H₂S can cause cytotoxic effects. Thus, the development of H₂S-associated neuroprotectors seems to be especially relevant. However, so far, all H₂S modulators are at the stage of preclinical trials. Nevertheless, many of them show a high neuroprotective effect in various animal models of neurotrauma and related disorders. Despite the fact that our review is very extensive and detailed, it is well structured right down to the conclusions, which will allow researchers to quickly find the proper information they are interested in.

Traumatic brain injury (TBI) is one of the leading causes of disability and death worldwide. It is characterized by various molecular–cellular events, with the main ones being apoptosis and damage to axons. To date, there are no clinically effective neuroprotective drugs. In this study, we examined the role of hydrogen sulfide (H₂S) in the localization and expression of the key pro-apoptotic protein p53, as well as cell death in the nervous tissue in TBI and axotomy. We used a fast donor (sodium sulphide, Na₂S) H₂S and a classic inhibitor (aminooxyacetic acid, AOAA) of cystathionine β-synthase (CBS), which is a key enzyme in H₂S synthesis. These studies were carried out on three models of neurotrauma in vertebrates and invertebrates. As a result, it was found that Na₂S exhibits a pronounced neuroprotective effect that reduces the number of TUNEL-positive neurons and glial cells in TBI and apoptotic glia in axotomy. This effect could be realized through the Na₂S-dependent decrease in the level of p53 in the cells of the nervous tissue of vertebrates and invertebrates, which we observed in our study. We also observed the opposite effect when using AOAA, which indicates the important role of CBS in the regulation of p53 expression and death of neurons and glial cells in TBI and axotomy.

Metabolic syndrome (MS) is a risk factor for cardiovascular diseases and cancer, although the complete relationship between MS and cancer remains a problem far from being resolved. Hormonal and inflammatory changes in adipose tissue were reported to be associated with cancer. Objective. To study the probability of cancer development in patients with MS. Material and methods. An observational retrospective study including 994 patients (289 males and 705 females) was carried out at the outpatient center of Moscow (Diagnostic Center No. 5 of the Moscow Healthcare Department). The mean age of study patients was 62.48±13.49 years (20 to 87 years). The incidence of cancer and oncogenesis factors in patients with MS over 10 years and the association between its components (abdominal obesity, arterial hypertension, hyperglycemia, and hypertriglyceridemia) were analyzed. Odds ratios of carcinogenesis and 95% confidence intervals were estimated using the cross tables method. Results. Cancer onset was observed in every fifth patient with an MS duration of 13.5±2.41 years. Abdominal obesity was associated with an increased risk of various cancers. The most significant risk was associated with grade I obesity, metabolic disorders, and the age of patients. In addition, a retrospective analysis of data from MS patients revealed a protective effect of oral antidiabetic and hypolipidemic agents on cancer risk and mortality, although the mechanisms are not fully understood. Conclusions. Metabolic syndrome is a risk factor for cardiovascular diseases and cancer. Cardiovascular diseases, particularly arterial hypertension, increase the risk of cancer several-fold. Hyperglycemia also increases the risk of malignant neoplasms. Dyslipidemia has no effect on cancer development; however, more detailed studies with a larger sample are needed.

The study’s objective was to comprehensively assess kidney function alterations in patients with COVID-19. The study was carried out in Moscow (Russia) in 2021. 100 patients of 19-30 years old (51 females and 49 males) took part in the survey. The study collected participant data on basal urine, serum creatinine, and estimated glomerular filtration rate from medical histories before COVID-19 infection. COVID-19 diagnosis (delta strain) was confirmed by polymerase chain reaction test. Serum creatinine was measured, considering age and race. Micro-albuminuria levels from daily urine samples were established. Laboratory blood tests included quantitative indices of blood-forming elements, hemoglobin levels, and biochemical parameters. Based on the results, the study observed a slight increase in serum creatinine levels after COVID-19 infection, with concentrations of 78.4±6.4 mmol/L before infection and 87.5±7.7 mmol/L after the disease (p≥0.05). The microalbuminuria-creatinine ratio also showed an increase. The glomerular filtration rate in renal glomeruli declined from 93.3±10.1 mL/min/1.73 m2 before infection to 78.9±8.7 mL/min/1.73 m2 after the disease (p≥0.05). These findings suggest a trend towards decreased kidney function in young patients with moderate COVID-19 severity. However, normoalbuminuric compared to creatinine was significantly higher than normal after COVID-19. Urine tests indicated a trend of decreased renal glomerular filtration rate. Clinical symptoms included high temperature, weakness, cough, and, in some cases, liquid stools. Laboratory findings revealed significant deviations in hematocrit, neutrophil, and eosinophil concentrations. Parallel tests focusing on cystatin C and beta-2 macroglobulin are recommended to assess kidney function and identify potential dysfunction.

Aim. To establish the role of the main risk factors and endocrine cells of the antrum of the stomach producing motilin (M-cells) in the occurrence of cholelithiasis. Materials and methods. The first group included 122 patients with cholelithiasis. The second group consisted of 30 healthy individuals who underwent medical examination. The groups were matched for gender and age. The work analyzed anamnestic, biochemical and anthropometric data. All patients underwent esophagogastroduodenoscopy with targeted biopsy of the mucous membrane from the antrum. Biopsies were subjected to cytological and immunohistochemical studies in order to verify Helicobacter pylori and estimate the number of M-cells. Results. Patients with cholelithiasis more often belonged to the group of people of mental labor, had low physical activity, were committed to inappropriate nutrition and more often indicated the presence of aggravated heredity for cholelithiasis. Patients with gallstone disease had higher body mass index, waist volume, total cholesterol, low-density lipoprotein cholesterol, triglycerides, glucose, lower high-density lipoprotein cholesterol, H. pylori infection was more often verified and M-cell hypoplasia in the mucous membrane was established. stomach in comparison with the representatives of the second group. Conclusion. Our results suggest that certain external factors, nutritional characteristics of the metabolic syndrome components, hypoplasia of M-cells in the gastric mucosa are important factors in the formation of calculi in the gallbladder.