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Background and aims of the study: Fluctuations in environmental temperature and humidity significantly affect human physiology and disease manifestation. In the Lingnan region of China, high summer temperatures and humidity often cause symptoms like diminished appetite, sticky tongue coating, sticky stool, unsatisfactory defecation, lethargy, and joint heaviness. These are referred to as "Dampness Syndrome" in Traditional Chinese Medicine (TCM). Thick and greasy tongue fur and sticky feces are characteristic symptoms of "Dampness Syndrome" and serve as crucial diagnostic indicators in TCM for assessing health conditions. However, the specific mechanisms that lead to these symptoms, such as sticky feces and thick and greasy tongue fur, have not been fully elucidated. Understanding these external symptoms is essential, as they reflect internal health status. Warm, humid environments favor microorganism growth, potentially disrupting gut microbiota and bacterial translocation, which could induce an immune-inflammatory response. The primary objective of this study is to explore the potential significant role of immune response products in influencing the proliferation and biofilm formation of gut microbiota, which may subsequently lead to changes in fecal characteristics. Methods: In this study, mice were exposed to a controlled warm and humid environment (25 ± 3 °C with 95% humidity) for 16 days to simulate conditions associated with "Dampness Syndrome." After this period, Huoxiang Zhengqi Water, a traditional remedy, has been administrated for four days. On the one hand saliva and tongue coating samples were also taken from human subjects with "Dampness Syndrome" for microorganism culturing and to assess biofilm formation, on the other hand the co-culture products of a macrophage cell line RAW264.7 and Candida albicans and the effect of tumor necrosis factor-α (TNF-α) were evaluated for their impact on the proliferation and biofilm-forming abilities of different bacterial strains. Results: Compared to a control group, the treatment group exhibited significant changes in gut microbiota, including increased biofilm formation, which was mitigated by Huoxiang Zhengqi Water. In the model group, fungal translocation was observed, potentially triggering an inflammatory response. Intraperitoneal injections of various bacterial strains in mice reproduced the sticky stool characteristics. Both mice and human subjects with "Dampness Syndrome" displayed elevated serum levels of inflammatory cytokines TNF-α and interleukin-17 A (IL-17A). Interestingly, Saliva samples from individuals with "Dampness Syndrome" showed elevated TNF-α levels, accompanied by thick and greasy tongue fur. Culturing samples from the tongue coating of individuals in the "Dampness Syndrome" group revealed an increased biofilm formation capability. C. albicans co-cultured with RAW264.7 cells increased TNF-α secretion, and the supernatant promoted pathogenic bacterial proliferation and biofilm formation. TNF-α specifically enhanced biofilm formation in microorganism like C. albicans and Staphylococcus aureus, with minimal effect on beneficial bacteria like Lacticaseibacillus paracasei and Lactiplantibacillus plantarum in the tested conditions. Conclusions: These findings provided new insights into the biological mechanisms of 'Dampness Syndrome' and support the therapeutic role of Huoxiang Zhengqi Water in treating symptoms associated with microbial dysbiosis and inflammation. Additionally, they indicate that TNF-α seems to have selective effects in promoting the proliferation and biofilm formation of different microbial species. [ABSTRACT FROM AUTHOR]

The concept of the gut-kidney axis is gaining significant attention due to the close relationship between gut microbiota and kidney disease. Peritoneal dialysis is recognized as a crucial renal replacement therapy for end-stage renal disease (ESRD). The alterations in gut microbiota and related mechanisms after receiving this dialysis method are not fully understood. This study conducted shotgun metagenomic sequencing on fecal samples from 11 end-stage renal disease patients who did not receive dialysis (ESRD_N) and 7 patients who received peritoneal dialysis (ESRD_P). After quality control and correlation analysis of the data, our study is aimed at exploring the impact of peritoneal dialysis on the gut microbiota and health of ESRD patients. Our research findings indicate that the complexity and aggregation characteristics of gut microbiota interactions increase in ESRD_P. In addition, the gut microbiota drives the biosynthesis pathways of sesquiterpenes and triterpenes in ESRD_P patients, which may contribute to blood purification and improve circulation. Therefore, our research will lay the foundation for the prevention and treatment of ESRD. [ABSTRACT FROM AUTHOR]

Background: Studies have found dysbiosis of the gut microbiota in individuals infected with the hepatitis B virus (HBV). Tenofovir dipivoxil (TDF) is one of the preferred oral antiviral drugs used for the treatment of chronic hepatitis B (CHB), but the extent to which TDF is able to affect the gut microbiota and inflammatory factors of a patient remains largely unexplored. In this study, we collected stool samples from HBV patients prior to medication and from CHB patients treated with TDF. Results: The gut microbiota and inflammatory factors were assessed in 42 healthy subjects (HC group), 109 HBV-infected subjects, including 48 CHB patients who were not medicated with nucleoside analogue drugs (No-NAs group), and 61 CHB patients who were medicated with TDF (TDF group). 16 S rRNA sequencing revealed that TDF treatment caused significant changes in the gut microbiota of HBV-infected individuals; however, the gut microbiota of HBV-infected individuals did not fully recover to a pre-dysbiosis state. The relative abundance of Bacteroidota gradually decreased from the HC group to the No-NAs and TDF groups. The relative abundance of Fusobacteriota was significantly higher in the No-NAs group than in the HC group. At the genus level, Dialister, Eubacterium_hallii_group, Halomonas, Collinsella, Sphingomonas, Xanthomonadaceae_unclassified, and Rhizobiaceae_unclassified were overrepresented; while the abundance of Bacteroides and Fusobacterium decreased significantly in the No-NAs and TDF groups. Conclusions: This study showed that TDF treatment significantly improved the regulation of the gut microbiota and aided in dysbiosis recovery. We did not observe significant improvement in serum inflammatory factor concentrations, which may be related to the relatively short duration of TDF administration in this study. [ABSTRACT FROM AUTHOR]

Background: The fall armyworm (FAW, Spodoptera frugiperda) is a polyphagous pest known for causing significant crop damage. The gut microbiota plays a pivotal role in influencing the biology, physiology and adaptation of the host. However, understanding of the taxonomic composition and functional characteristics of the gut microbiota in FAW larvae fed on different host plants remains limited. Methods: This study utilized metagenomic sequencing to explore the structure, function and antibiotic resistance genes (ARGs) of the gut microbiota in FAW larvae transferred from an artificial diet to four distinct host plants: maize, sorghum, tomato and pepper. Results: The results demonstrated significant variations in gut microbiota structure among FAW larvae fed on different host plants. Firmicutes emerged as the dominant phylum, with Enterococcaceae as the dominant family and Enterococcus as the prominent genus. Notably, Enterococcus casseliflavus was frequently observed in the gut microbiota of FAW larvae across host plants. Metabolism pathways, particularly those related to carbohydrate and amino acid metabolism, played a crucial role in the adaptation of the FAW gut microbiota to different host plants. KEGG orthologs associated with the regulation of the peptide/nickel transport system permease protein in sorghum-fed larvae and the 6-phospho-β-glucosidase gene linked to glycolysis/gluconeogenesis as well as starch and sucrose metabolism in pepper-fed larvae were identified. Moreover, the study identified the top 20 ARGs in the gut microbiota of FAW larvae fed on different host plants, with the maize-fed group exhibiting the highest abundance of vanRC. Conclusions: Our metagenomic sequencing study reveals significant variations in the gut microbiota composition and function of FAW larvae across diverse host plants. These findings underscore the intricate co-evolutionary relationship between hosts and their gut microbiota, suggesting that host transfer profoundly influences the gut microbiota and, consequently, the adaptability and pest management strategies for FAW. [ABSTRACT FROM AUTHOR]

Background Exposure to extreme cold or heat temperature is one leading cause of weather-associated mortality and morbidity in animals. Emerging studies demonstrate that the microbiota residing in guts act as an integral factor required to modulate host tolerance to cold or heat exposure, but common and unique patterns of animaltemperature associations between cold and heat have not been simultaneously examined. Therefore, we attempted to investigate the roles of gut microbiota in modulating tolerance to cold or heat exposure in mice. Results The results showed that both cold and heat acutely change the body temperature of mice, but mice efficiently maintain their body temperature at conditions of chronic extreme temperatures. Mice adapt to extreme temperatures by adjusting body weight gain, food intake and energy harvest. Fascinatingly, 16 S rRNA sequencing shows that extreme temperatures result in a differential shift in the gut microbiota. Moreover, transplantation of the extreme-temperature microbiota is sufficient to enhance host tolerance to cold and heat, respectively. Metagenomic sequencing shows that the microbiota assists their hosts in resisting extreme temperatures through regulating the host insulin pathway. Conclusions Our findings highlight that the microbiota is a key factor orchestrating the overall energy homeostasis under extreme temperatures, providing an insight into the interaction and coevolution of hosts and gut microbiota. [ABSTRACT FROM AUTHOR]

Mounting evidence indicates that the gut microbiota influences the neurodevelopment and behavior of insects through the gut-brain axis. However, it is currently unclear whether the gut microbiota affect the head profiles and immune pathway in pests. Here, we find that gut bacteria is essential for the immune and neural development of adult Spodoptera frugiperda, which is an extremely destructive agricultural pest worldwide. 16 S rRNA sequencing analysis showed that antibiotics exposure significantly disturbed the composition and diversity of gut bacteria. Further transcriptomic analysis revealed that the adult head transcripts were greatly affected by gut dysbacteriosis, and differently expression genes critical for brain and neural development including A4galt, Tret1, nsun4, Galt, Mitofilin, SLC2A3, snk, GABRB3, Oamb and SLC6A1 were substantially repressed. Interestingly, the dysbacteriosis caused sex-specific differences in immune response. The mRNA levels of pll (serine/threonine protein kinase Pelle), PGRP (peptidoglycan-sensing receptor), CECA (cecropin A) and CECB (cecropin B) involved in Toll and Imd signaling pathway were drastically decreased in treated male adults' heads but not in female adults; however, genes of HIVEP2, ZNF131, inducible zinc finger protein 1-like and zinc finger protein 99-like encoding zinc-finger antiviral protein (ZAP) involved in the interferon (IFNα/β) pathway were significantly inhibited in treated female adults' heads. Collectively, these results demonstrate that gut microbiota may regulate head transcription and impact the S. frugiperda adults' heads through the immune pathway in a sex-specific manner. Our finding highlights the relationship between the gut microbiota and head immune systems of S. frugiperda adults, which is an astonishing similarity with the discoveries of other animals. Therefore, this is the basis for further research to understand the interactions between hosts and microorganisms via the gut-brain axis in S. frugiperda and other insects. [ABSTRACT FROM AUTHOR]

The biological mechanisms underlying meat quality remain unclear. Currently, many studies report that the gastrointestinal microbiota is essential for animal growth and performance. However, it is uncertain which bacterial species are specifically associated with the meat quality traits. In this study, 16S rDNA and metagenomic sequencing were performed to explore the composition and function of microbes in various gastrointestinal segments of Tan sheep and Dorper sheep, as well as the relationship between microbiota and meat quality (specifically, the fatty acid content of the muscle). In the ruminal, duodenal, and colonic microbiome, several bacteria were uniquely identified in respective breeds, including Agrobacterium tumefaciens, Bacteroidales bacterium CF, and several members of the family Oscillospiraceae. The annotation of GO, KEGG, and CAZYme revealed that these different bacterial species were linked to the metabolism of glucose, lipids, and amino acids. Additionally, our findings suggested that 16 microbial species may be essential to the content of fatty acids in the muscle, especially C12:0 (lauric acid). 4 bacterial species, including Achromobacter xylosoxidans, Mageeibacillus indolicus, and Mycobacterium dioxanotrophicus, were positively correlated with C12:0, while 13 bacteria, including Methanobrevibacter millerae, Bacteroidales bacterium CF, and Bacteroides coprosuis were negatively correlated with C12:0. In a word, this study provides a basic data for better understanding the interaction between ruminant gastrointestinal microorganisms and the meat quality traits of hosts. [ABSTRACT FROM AUTHOR]