The present study aimed to investigate the neuroprotective effects of the vitamin B complex (B1, B2, B3, B5, B6, and B12—VBC), by studying the changes in the femoral nerve, quadriceps muscle, popliteal lymph nodes and gut microbiota in the rat model of multiple sclerosis, experimental autoimmune encephalomyelitis (EAE). VBC treatment attenuated clinical signs of EAE during the disease, and reduced the duration of EAE thereby contributing to a faster recovery. In VBC-treated EAE rats, a significant decrease in nerve and muscle nuclear density was revealed during the onset period of the disease, while a marked increase was detected at the end of the disease, compared with untreated EAE rats. In the lymph nodes of VBC-treated EAE rats, a fewer number of lymphoid follicles in the cortical area and smaller epithelioid granulomas were detected. The changes in microbiota composition were examined using 16S rRNA gene sequencing and bioinformatics analysis, which revealed the potential of VBC treatment in establishing and/or maintaining gut microbiota homeostasis. Finally, the present study demonstrated that VBC treatment ameliorated the cellular changes in the affected peripheral nerve, muscles innervated by this nerve, and the gut microbiota dysbiosis which occurred during the EAE.

Neuroinflammation plays a central role in the pathogenesis of neurodegenerative diseases, and there is increasing interest in identifying natural compounds with anti-neuroinflammatory and neuroprotective effects. In this study, we aimed to investigate the biological activities of ethanol and ethyl acetate extracts from five moss species (Dicranum scoparium, Fontinalis antipyretica, Hypnum cupressiforme, Polytrichum formosum, and Tortella tortuosa) with a focus on their neuroprotective and anti-neuroinflammatory potential. Phytochemical profiling revealed the presence of phenols (up to 24.77 mg GAE/g), phenolic acids (up to 235.48 mg CAE/g), and triterpenoids (up to 367.98 mg UAE/g). A series of in vitro assays, including acetylcholinesterase (AChE) and tyrosinase inhibition, MTT, NBT, Griess, and ELISA, were used to assess their bioactivity. Several extracts, particularly ethanolic, significantly inhibited AChE activity, while tyrosinase inhibition was moderate and concentration-dependent. Most extracts maintained >85% cell metabolic activity in BV2 mouse microglia and L929 mouse fibroblasts. Moss extracts significantly suppressed lipopolysaccharide (LPS)-induced production of reactive oxygen species (ROS), nitric oxide (NO), interleukin 6 (IL-6), and tumor necrosis factor alpha (TNF-α) in BV2 cells and reduced microglia-mediated neurotoxicity in undifferentiated SH-SY5Y cells. These findings indicate that moss-derived extracts possess promising anti-neuroinflammatory and neuroprotective properties that warrant further investigation.

The dietary habits of fruit flies profoundly influence their fitness, morphology, and physiology yet the mechanisms underlying these effects remain incompletely understood. To address this gap, the relationship between dietary regimens and the composition and function of adult Drosophila melanogaster microbiota was investigated in the present study. The adult fly microbiota communities that were reared for long time on five different diets were characterized by means of 16S rRNA sequencing. Obtained results revealed distinct community structures associated with each dietary regimen, which was additionally corroborated through machine learning-based analysis. In general, sugar-rich diets correlate with microbial ecosystems of higher richness/diversity. Dominance of the phyla Proteobacteria and Firmicutes in the microbiota was confirmed irrespective of diet, with the varying proportions of the most abundant families: Acetobacteraceae, Lactobacillaceae, Moraxellaceae, Bradyrhizobiaceae, and Leucostonocaceae. Bacterial families of lower abundance also emerged as differentially present among the studied fly groups. Additionally, functional prediction provided initial clues into how nutrient availability might modulate the metabolic traits of adult fly microbiota in a sex-specific manner to meet host metabolic needs. Overall, the presented findings highlight the intricate interplay between diet, microbiota composition, and host phenotype in fruit flies, underscoring the importance of diet as a determinant of host-microbiota interactions.