[The intestinal microbiota composition in patients with multiple sclerosis receiving different disease-modifying therapies DMT]. / Osobennosti sostava mikrobioty kishechnika u patsientov s rasseiannym sklerozom, poluchaiushchikh preparaty, izmeniaiushchie techenie rasseiannogo skleroza.

AIM: To describe characteristics of the intestinal microbiota in patients with multiple sclerosis (MS) treated with glatiramer acetate (GA) or fingolimode (FG) for understanding causal relationships between gut microbiota and autoimmune processes in MS patients. MATERIAL AND METHODS: The study included 34 patients treated with GA (n=17) or FG (n=17). GA was used in a dose of 20 mg/kg subcutaneously once a day, FG in a dose of 0.5 mg daily. All patients were examined during remission. To assess the composition of gut microbiota, bacteriological and real-time PCR techniques were used. DNA was extracted from feces using DNA-EXPRESS kit. RESULTS AND CONCLUSION: There was a decrease in numbers of Escherichia coli with normal enzymatic activity, which was replaced by atypical forms of E. coli, Enterobacter spp. and fungi of the genus Candida, and, during treatment with GA, by atypical forms of E. coli, Proteus spp., Parvimonas micra. These differences indicate the effect of the therapy on the intestinal microbiota composition.

Impairment of non-associative learning in a rat experimental model of preclinical stage of Parkinson's disease.

An experimental model of the preclinical stage of Parkinson's disease was induced by double intranasal administration of the proteasome inhibitor lactacystin. The results demonstrated signs of cognitive impairments expressed as impaired non-associative learning. This was related to degeneration of one-third of dopaminergic neurons in the ventral tegmental area of the midbrain and their axons in the dorsolateral prefrontal cortex. Impairment of non-associative learning may be an early non-motor marker of Parkinson's disease indicating the start of neurodegenerative processes in the dopaminergic mesocortical system of the brain.

Enterococcus faecium strain L-3 and glatiramer acetate ameliorate experimental allergic encephalomyelitis in rats by affecting different populations of immune cells.

The effect of probiotic Enterococcus faecium strain L-3 was studied in rats with experimental allergic encephalomyelitis (EAE). Glatiramer acetate (GA) was used as control drug. E. faecium strain L-3 and GA both were able to reduce the severity of EAE in a similar fashion. Both approaches increased the proportion of EAE resistant rats and rats with mild disease, prolonged the inductive phase of EAE and reduced the disease duration. Study of the phenotypes of immune cells in blood revealed the differences in immunoregulatory pathways that mediate the protective action of probiotic or GA treatment of EAE. The presence of pronounced protective and immunomodulating effects of the probiotic E. faecium strain L-3 opens an opportunity of its application for the treatment of multiple sclerosis.

[EFFECT OF PROBIOTIC ENTEROCOCCI AND GLATIRAMER ACETATE ON THE SEVERITY OF EXPERIMENTAL ALLERGIC ENCEPHALOMYELITIS IN RATS ].

Currently intestinal microbiota is considered as a potential target for influence in various pathologies which have inflammation, autoimmunity or neurodegeneration in the genesis. Multiple sclerosis (MS) combines all these processes in the pathogenesis. Furthermore, the balance of the components of intestinal microbiota is disrupted during MS and followed by disbiosis. Different probiotics - bacteria with proven beneficial properties are widely used to correct dysbisis. In this paper, was investigated the ability of probiotic strain Enterococcus faecium L-3 to reduce disease severity in multiple sclerosis model - experimental allergic encephalomyelitis (EAE). E. faecium L-3 were used alone or in combination with glatiramer acetate (GA). It is shown that administration of E. faecium L-3 reduces the severity of EAE in rats almost as same as that of GA. However, when the probiotic enterococci administered together with GA the protective effect does not observed. It is assumed that these preparations stimulates different ways of the immune system, because their action stimulate different immune cells populations. The study demonstrates the ability of E. faecium L-3 to influence on the immune system in MS, directly and indirectly (through the correction of dysbiosis). This fact allows us to consider E. faecium L-3 as a potential tool for immunomodulation in autoimmune, inflammatory and neurodegenerative diseases.

[CHANGES IN THE QUALITATIVE AND QUANTITATIVE COMPOSITION OF GUT MICROBIOTA IN RATS DURING EXPERIMENTAL ALLERGIC ENCEPHALOMYELITIS].

In this study, on the model of multiple sclerosis - experimental allergic encephalomyelitis (EAE), the dynamics of changes in the qualitative and quantitative composition of the intestinal microbiota in rats with symptoms of the disease and asymptomatic course were compared. It was found that the composition of the intestinal microbiota in rats with the clinical symptoms of EAE is shifted towards gram-negative opportunistic microorganisms of the genus Citrobacter, Prote- us, Klebsiella and enteropathogenic Escherichia coli. It has been shown that rats without clinical signs of EAE have higher levels of Faecalibacteriumprausnitzii. The significance of the complex changes in the composition of the intestinal microbiota, indicating long-lasting dysbiosis in rats during the development of EAE is discussing.