Immunomodulation by Bifidobacterium animalis subsp. lactis Bb12: Integrative Analysis of miRNA Expression and TLR2 Pathway-Related Target Proteins in Swine Monocytes

Probiotics in miRNA-Mediated Regulation of Intestinal Immune Homeostasis in Pigs: A Physiological Narrative

The microbiota plays a crucial role in maintaining the host's intestinal homeostasis, influencing numerous physiological functions. Various factors, including diet, stress, and antibiotic use, can lead to such imbalances. Probiotics have been shown to restore the microbiota, contributing to maintaining this balance. For instance, the weaning stage in piglets is crucial; this transition can cause unfavorable changes that may contribute to the onset of diarrhea. Probiotic supplementation has increased due to its benefits. However, its mechanism of action is still controversial; one involves the regulation of intestinal immunity. When recognized by immune system cells through membrane receptors, probiotics activate intracellular signaling pathways that lead to changes in gene expression, resulting in an anti-inflammatory response. This complex regulatory system involves transcriptional and post-transcriptional mechanisms, including the modulation of various molecules, emphasizing microRNAs. They have emerged as important regulators of innate and adaptive immune responses. Analyzing these mechanisms can enhance our understanding of probiotic-host microbiota interactions, providing insights into their molecular functions. This knowledge can be applied not only in the swine industry, but also in studying microbiota-related disorders. Moreover, these studies serve as animal models, helping to understand better conditions such as inflammatory bowel disease and other related disorders.

Integrated metabolome-microbiome analysis investigates the different regulations of Pudilan Xiaoyan oral liquid in young rats with acute pharyngitis compared to adult rats

BACKGROUND

Pudilan Xiaoyan Oral Liquid (PDL) is a famous traditional Chinese prescription recorded in the Chinese Pharmacopeia, which is widely used to treat inflammatory diseases of the respiratory tract in children and adults. However, the endogenous changes in children and adults with PDL in the treatment of acute pharyngitis remain unclear.

PURPOSE

The differential regulatory roles of PDL in endogenous metabolism and gut microbes in young and adult rats were investigated with a view to providing a preclinical data reference for PDL in medication for children.

METHODS

An acute pharyngitis model was established, and serum levels of inflammatory factors and histopathology were measured. This study simulated the growth and development of children in young rats and explored the endogenous metabolic characteristics and intestinal microbial composition after the intervention of PDL by using serum metabolomic technique and 16S rRNA high-throughput sequencing technique.

RESULTS

The results showed that PDL had therapeutic effects on young and adult rats with acute pharyngitis. Sixteen biomarkers were identified by metabolomics in the serum of young rats and 23 in adult rats. PDL can also affect intestinal microbial diversity and community richness in young and adult rats. Alloprevotella, Allobaculum, Alistipes, Bifidobacterium, and Enterorhabdus were prominent bacteria in young rats. Bacteria from the phylum Firmicutes of the adult rats changed more significantly under the treatment of PDL. In young rats, amino acid metabolism was the primary regulatory mode of PDL, whereas, in adult rats, glycerophospholipid metabolism was studied.

CONCLUSION

The regulation of PDL on the serum metabolite group and intestinal microflora in young rats was different from that in adult rats, indicating the necessity of an independent study on children's medication. PDL may also exert therapeutic effects on young and adult rats by regulating gut microbial homeostasis. The results support the clinical application of PDL.

Diagnostic, Prognostic, and Therapeutic Roles of Gut Microbiota in COVID-19: A Comprehensive Systematic Review

Introduction

The Coronavirus Disease 2019 (COVID-19) pandemic caused by Severe Acute Respiratory Coronavirus 2 (SARS-CoV-2) emerged in late December 2019. Considering the important role of gut microbiota in maturation, regulation, and induction of the immune system and subsequent inflammatory processes, it seems that evaluating the composition of gut microbiota in COVID-19 patients compared with healthy individuals may have potential value as a diagnostic and/or prognostic biomarker for the disease. Also, therapeutic interventions affecting gut microbial flora may open new horizons in the treatment of COVID-19 patients and accelerating their recovery.

Methods

A systematic search was conducted for relevant studies published from December 2019 to December 2021 using Pubmed/Medline, Embase, and Scopus. Articles containing the following keywords in titles or abstracts were selected: "SARS-CoV-2" or "COVID-19" or "Coronavirus Disease 19" and "gastrointestinal microbes" or "dysbiosis" or "gut microbiota" or "gut bacteria" or "gut microbes" or "gastrointestinal microbiota".

Results

Out of 1,668 studies, 22 articles fulfilled the inclusion criteria and a total of 1,255 confirmed COVID-19 patients were examined. All included studies showed a significant association between COVID-19 and gut microbiota dysbiosis. The most alteration in bacterial composition of COVID-19 patients was depletion in genera Ruminococcus, Alistipes, Eubacterium, Bifidobacterium, Faecalibacterium, Roseburia, Fusicathenibacter, and Blautia and enrichment of Eggerthella, Bacteroides, Actinomyces, Clostridium, Streptococcus, Rothia, and Collinsella. Also, some gut microbiome alterations were associated with COVID-19 severity and poor prognosis including the increment of Bacteroides, Parabacteroides, Clostridium, Bifidobacterium, Ruminococcus, Campylobacter, Rothia, Corynebacterium, Megasphaera, Enterococcus, and Aspergillus spp. and the decrement of Roseburia, Eubacterium, Lachnospira, Faecalibacterium, and the Firmicutes/Bacteroidetes ratio.

Conclusion

Our study showed a significant change of gut microbiome composition in COVID-19 patients compared with healthy individuals. This great extent of impact has proposed the gut microbiota as a potential diagnostic, prognostic, and therapeutic strategy for COVID-19. There is much evidence about this issue, and it is expected to be increased in near future.