Insects are the most abundant animals on Earth, and the microbiota within their guts play important roles by engaging in beneficial and pathological interactions with these hosts. In this study, we ...comprehensively characterized insect-associated gut bacteria of 305 individuals belonging to 218 species in 21 taxonomic orders, using 454 pyrosequencing of 16S rRNA genes. In total, 174,374 sequence reads were obtained, identifying 9,301 bacterial operational taxonomic units (OTUs) at the 3% distance level from all samples, with an average of 84.3 (± 97.7) OTUs per sample. The insect gut microbiota were dominated by Proteobacteria (62.1% of the total reads, including 14.1% Wolbachia sequences) and Firmicutes (20.7%). Significant differences were found in the relative abundances of anaerobes in insects and were classified according to the criteria of host environmental habitat, diet, developmental stage, and phylogeny. Gut bacterial diversity was significantly higher in omnivorous insects than in stenophagous (carnivorous and herbivorous) insects. This insect-order-spanning investigation of the gut microbiota provides insights into the relationships between insects and their gut bacterial communities.
Castration of young males is widely used in the cattle industry to improve meat quality, but the mechanism linking hypogonadism and host metabolism is not clear. Here, we use metataxonomic and ...metabolomic approaches to evaluate the intestinal microbiota and host metabolism in male, castrated male (CtM), and female cattle. After pubescence, the CtM cattle harbor distinct ileal microbiota dominated by the family Peptostreptococcaceae and exhibit distinct serum and muscle amino acid profiles (i.e., highly abundant branched‐chain amino acids), with increased extra‐ and intramuscular fat storage. We also evaluate the causative factor(s) that underpin the alteration of the intestinal microbiota and host metabolic phenotype in response to hypogonadism. Castration of male mice phenocopies both the intestinal microbial alterations and obese‐prone metabolism observed in cattle. Antibiotic treatment and fecal microbiota transplantation experiments in a mouse model confirm that the intestinal microbial alterations associated with hypogonadism are a key contributor to the obese phenotype in the CtM animals. Collectively, targeting the gut microbiota is a potential therapeutic strategy for the treatment of both hypogonadism and obesity.
Synopsis
Primary hypogonadism caused in cattle and mouse by male castration leads to alterations of the ileal microbiota. These changes induce aberrant systemic, muscular and intestinal metabolome profiles, resulting in increased fat storage.
Male castration alters the gut microbial profile, with a marked increase in the ileal abundance of Peptostreptococcaceae.
Hypogonadal animals have distinct metabolomic signatures, characterized by high levels of branched‐chain amino acids.
Obese phenotypes linked to hypogonadism are transferrable by fecal microbiota transplantation to a eugonadal recipient.
Primary hypogonadism caused in cattle and mouse by male castration leads to alterations of the ileal microbiota. These changes induce aberrant systemic, muscular and intestinal metabolome profiles, resulting in increased fat storage.
Despite the fungal abundance in honey and bee bread, little is known about the fungal gut community of the honey bee and its effect on host fitness. Using pyrosequencing of the 16S rRNA gene and ITS2 ...region amplicons, we analysed the bacterial and fungal gut communities of the honey bee as affected by the host social status. Both communities were significantly affected by the host social status. The bacterial gut community was similar to those characterised in previous studies. The fungal gut communities of most worker bees were highly dominated by Saccharomyces but foraging bees and queens were colonised by diverse fungal species and Zygosaccharomyces, respectively. The high fungal density and positive correlation between Saccharomyces species and Lactobacillus species, known yeast antagonists, were only observed in the nurse bee; this suggested that the conflict between Saccharomyces and Lactobacillus was compromised by the metabolism of the host and/or other gut microbes. PICRUSt analysis revealed significant differences in enriched gene clusters of the bacterial gut communities of the nurse and foraging bees, suggesting that different host social status might induce changes in the gut microbiota, and, that consequently, gut microbial community shifts to adapt to the gut environment.
Alterations in the gut microbiota play a crucial role in host physiology and metabolism; however, the molecular pathways underlying these changes in diet-induced obesity are unclear. Mechanistic ...target of rapamycin (mTOR) signaling pathway is associated with metabolic disorders such as obesity and type 2 diabetes (T2D). Therefore, we examined whether changes in the regulation of mTOR signaling induced by diet (a high-fat diet HFD or normal-chow diet) and/or therapeutics (resveratrol a specific inhibitor of mTOR complex 1 or rapamycin an inhibitor of both mTOR complex 1 and 2) altered the composition of the gut microbiota in mice. Oral administration of resveratrol prevented glucose intolerance and fat accumulation in HFD-fed mice, whereas rapamycin significantly impaired glucose tolerance and exacerbated intestinal inflammation. The abundance of Lactococcus, Clostridium XI, Oscillibacter, and Hydrogenoanaerobacterium increased under the HFD condition; however, the abundance of these species declined after resveratrol treatment. Conversely, the abundance of unclassified Marinilabiliaceae and Turicibacter decreased in response to a HFD or rapamycin. Taken together, these results demonstrated that changes in the composition of intestinal microbiota induced by changes in mTOR activity correlate with obese and diabetic phenotypes.
Our understanding of the gut microbiota of animals is largely based on studies of mammals. To better understand the evolutionary basis of symbiotic relationships between animal hosts and indigenous ...microbes, it is necessary to investigate the gut microbiota of non-mammalian vertebrate species. In particular, fish have the highest species diversity among groups of vertebrates, with approximately 33,000 species. In this study, we comprehensively characterized gut bacterial communities in fish.
We analyzed 227 individual fish representing 14 orders, 42 families, 79 genera, and 85 species. The fish gut microbiota was dominated by Proteobacteria (51.7%) and Firmicutes (13.5%), different from the dominant taxa reported in terrestrial vertebrates (Firmicutes and Bacteroidetes). The gut microbial community in fish was more strongly shaped by host habitat than by host taxonomy or trophic level. Using a machine learning approach trained on the microbial community composition or predicted functional profiles, we found that the host habitat exhibited the highest classification accuracy. Principal coordinate analysis revealed that the gut bacterial community of fish differs significantly from those of other vertebrate classes (reptiles, birds, and mammals).
Collectively, these data provide a reference for future studies of the gut microbiome of aquatic animals as well as insights into the relationship between fish and their gut bacteria, including the key role of host habitat and the distinct compositions in comparison with those of mammals, reptiles, and birds. Video Abstract.
Pectin is a complex structural polysaccharide located in the cell wall and middle lamella of higher plants. The homogalacturon (HG) regions may be methyl esterified or de-esterified to create a block ...co-polymer structure. The HG backbone may be interrupted by neutral sugar side chains forming the rhamnogalacturon I (RGI) region, or rhamnogalacturon II (RGII), a conserved structure. In addition, protein, ferulic acid and acetyl groups may be found on some sources of pectin. While pectin has positive health effects against many diseases related to inflammation and as a delivery vehicle for bioactives for colon targeted delivery, conflicting results are reported and may be related to paucity of physico-chemical information or source of pectin. Pectin structure can be enzymatically or chemically modified to produce molecular fragments that can be used to successfully entrap phytochemicals for emulsion based targeted delivery to the colon. Likewise, charge modified pectin allows the development of delivery systems based on hydrogel technology. Pectin is recognized as a soluble dietary fiber, and likely has multiple outcomes against cardiovascular disease. More recent evidence also points to the role of neutral sugars, arabino-oligosaccharides, and ferulic acid and other phenolics associated with pectin as a dietary fiber and in vitro fermentability of selected domains of pectin and associated colonic metabolites on inflammation and gut health. While the mechanism of the positive effects of pectin remain to be elucidated, emerging evidence points to synergism between specific domains of pectin structure and other food constituents.
Display omitted
•Pectin as soluble fiber has health promoting and drug delivery functionality.•Domains of structure influence bioactivity.•Paucity of data that relates specific structural domains to bioactivity.•Synergism of pectin with other molecules is likely.
Human gut microbiota plays important roles in harvesting energy from the diet, stimulating the proliferation of the intestinal epithelium, developing the immune system, and regulating fat storage in ...the host. Characterization of gut microbiota, however, has been limited to western people and is not sufficiently extensive to fully describe microbial communities. In this study, we investigated the overall composition of the gut microbiota and its host specificity and temporal stability in 20 Koreans using 454-pyrosequencing with barcoded primers targeting the V1 to V3 region of the bacterial 16S rRNA gene. A total of 303,402 high quality reads covered each sample and 8,427 reads were analyzed on average. The results were compared with those of individuals from the USA, China and Japan. In general, microbial communities were dominated by five previously identified phyla: Actinobacteria, Firmicutes, Bacteroidetes, Fusobacteria, and Proteobacteria. UPGMA cluster analysis showed that the species composition of gut microbiota was host-specific and stable over the duration of the test period, but the relative abundance of each member fluctuated. 43 core Korean gut microbiota were identified by comparison of sequences from each individual, of which 15 species level phylotypes were related to previously-reported butyrate-producing bacteria. UniFrac analysis revealed that human gut microbiota differed between countries: Korea, USA, Japan and China, but tended to vary less between individual Koreans, suggesting that gut microbial composition is related to internal and external characteristics of each country member such as host genetics and diet styles.
Calcium deficiency is a worldwide problem affecting both developed and developing countries. The deficiency in calcium leads to a marked decrease of superoxide dismutase. It is known that vitamin D ...protects cells against oxidative damages while taurine plays an anti-inflammatory and antioxidant role. In this study, we examined whether vitamin D and taurine supplementation had a protective effect on oxidative stress in rats fed calcium deficient diet. Female SD rats (mean weight 60 ∼ 70 g) were divided into four groups; control, taurine, vitamin D, taurine + vitamin D for 6 weeks (taurine: 2 g/100 g diet, vitamin D: 0.5 mg/100 g diet). We then analyzed the level of triglyceride (TG), total cholesterol (TC), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C) in serum and level of TC, TG in liver. We investigated antioxidative enzyme activities such as catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px). We observed that weight gain was not significantly different in the experimental groups. Food efficiency ratio (FER) was significantly higher in the normal control group than the taurine and vitamin D groups (p < 0.05). The level of liver TC was significantly lower in taurine, vitamin D, taurine + vitamin D groups than control group (p < 0.05). The concentration of malondialdehyde (MDA) was significantly lower in the taurine group than the control group. The activity of SOD was higher in taurine group than other experimental groups (p < 0.05), but GSH-Px and CAT were not significantly different. In conclusion, taurine has a positive effect on SOD activity but not on vitamin D. Also taurine and vitamin D have a protective effect as observed in liver TC in rats fed with a diet which lacks calcium.
Display omitted
•We study the impact of lactic acid bacteria (LAB) starters on microbial composition in kimchi fermentation.•Bacteriophages modulate bacterial communities associated with ...fermentation.•Microbial composition differences impacted the metabolites produced in kimchi.•LAB starters are an important factor contributing to fermented food quality.
Lactic acid bacteria (LAB) in kimchi, a traditional Korean food, are major fermentative microorganisms affecting the quality, safety, and nutritional and organoleptic properties of the final product. In this study, we determined the role of three key LAB strains, Leuconostoc gelidum, Latilactobacillus sakei, Weissella koreensis originated from different raw ingredients during natural fermentation, as opposed to an axenic environment. Starter cultures were inoculated into food with wild indigenous microbial communities, and the dynamics of bacterial communities and metabolites were analyzed during fermentation. As bacteriophages within the food viral community directly affect fermentation by influencing bacterial function and composition, the diversity and composition of DNA viral communities were compared with those of corresponding bacterial communities using a metagenomic approach. Our results provide insights into the ecological role of LAB starters in food fermentation and the potential impact of bacteriophages as modulators of bacterial communities associated with the fermentation properties of kimchi.
With the recent advances in medicine, patients with congenital heart disease are surviving to adulthood. Adults with congenital heart disease must practice self-management to recognize the symptoms ...of complications and the appropriate response.
The purpose of this study was to develop a self-management efficacy promotion program for adults with congenital heart disease and to test the effects of the developed program on disease-related knowledge, self-management implementation and health-related quality of life.
A non-equivalent, control group, pre-post test design was used. The intervention group received the self-management efficacy promotion program for six weeks. The control group received only the usual care.
The study results showed that disease-related knowledge ( F=91.095, p<0.001) was significantly different between the two groups, as was the self-management performance ( F=11.846, p<0.001). However, health-related quality of life (generic core scale: F=0.023, p=0.881, cardiac module scale: F=0.174, p=0.678) was not significantly different between groups.
The self-management efficacy promotion program for adults with congenital heart disease had a significant effect on disease-related knowledge and self-management implementation, but did not affect health-related quality of life.
PDF
