Gut Microbe-Metabolite Profiles Are Associated with Microbial Pathways of Longevity in Women: A Cross-Sectional Study Conducted in China.

INTRODUCTION: Recent research on the gut deepens people's understanding of the role of gut microbe-metabolites in longevity. However, most of the longevity population is female, and the gut microbe-metabolites associated with longevity in women remain unknown. Here, we hypothesize that the gut microbe-metabolite levels differed between the longevity women (LW, age ≥90) and the elderly women (EW, 60 < age <90). METHODS: We performed a cross-sectional study of 22 women in Guangxi longevity areas. 16S rRNA full-length sequencing, bioinformatic analysis, and nuclear magnetic resonance hydrogen spectra were determined to analyze the gut microbiota, microbial pathways, and fecal metabolites. We evaluated significant differences and relationships in gut microbe-metabolites and microbial pathways using the Mann-Whitney test and Spearman correlation, respectively. RESULTS: The EW experienced gut dysbiosis characterized by a higher Firmicutes/Bacteroidetes (F/B) value. The LW showed a higher abundance of Bacteroides and Alistipes, which might support health maintenance. Moreover, LW enriched alanine, aspartate, and glutamate metabolism, histidine metabolism, and pyruvate metabolism, leading to major changes in histidine, fumaric acid, acetate, valine, and aspartate. Interestingly, the most valuable metabolic pathway based on differential fecal metabolites confirmed the KEGG microbial pathway "alanine, aspartate, and glutamate metabolism" enriched in LW. Impressively, Bacteroides and Alistipes were positively correlated with alanine, aspartate, and glutamate metabolism, thus improving the level of aspartate, which could be a particular pathway related to longevity. CONCLUSION: The enriched gut genus and microbial pathways in LW showed a significant correlation, which might mediate the production of metabolites related to longevity.

Longevity-Associated Core Gut Microbiota Mining and Effect of Mediated Probiotic Combinations on Aging Mice: Case Study of a Long-Lived Population in Guangxi, China.

With an ageing population, healthy longevity is becoming an important scientific concern. The longevity phenomenon is closely related to the intestinal microflora and is highly complicated; it is challenging to identify and define the core gut microbiota associated with longevity. Therefore, in this study, 16S rRNA sequencing data were obtained from a total of 135 faecal samples collected as part of the latest sampling and pre-collection initiative in the Guangxi longevity area, and weighted gene co-expression network analysis (WGCNA) was used to find a mediumpurple3 network module significantly associated with the Guangxi longevity phenomenon. Five core genera, namely, Alistipes, Bacteroides, Blautia, Lachnospiraceae NK4A136 group, and Lactobacillus, were identified via network analysis and random forest (RF) in this module. Two potential probiotic strains, Lactobacillus fermentum and Bacteroides fragilis, were further isolated and screened from the above five core genera, and then combined and used as an intervention in naturally ageing mice. The results show a change in the key longevity gut microbiota in mice toward a healthy longevity state after the intervention. In addition, the results show that the probiotic combination effectively ameliorated anxiety and necrosis of hippocampal neuronal cells in senescent mice, improving their antioxidant capacity and reducing their inflammation levels. In conclusion, this longer-term study provides a new approach to the search for longevity hub microbiota. These results may also provide an important theoretical reference for the healthification of the intestinal microflora in the general population, and even the remodelling of the structure of the longevity-state intestinal microflora.

Combined effects of elevated temperature and CO2 enhance threat from low temperature hazard to winter wheat growth in North China.

We examined the growth and yield of winter wheat (Triticum aestivum) in response to the predicted elevated CO2 concentration and temperature to determine the mechanism of the combined impacts in North China Plain. An elevated treatment (CO2: 600 µmol mol-1, temperature: +2.5~3.0 °C, ECTI) and a control treatment (ambient CO2 and temperature, CK) were conducted in open-top chambers from October 2013 to June 2016. Post-winter growth stages of winter wheat largely advanced and shifted to a cooler period of nature season under combined impact of elevated CO2 and temperature during the entire growing season. The mean temperature and accumulated photosynthetic active radiations (PAR) over the post-winter growing period in ECTI decreased by 0.8-1.5 °C and 10-13%, respectively compared with that in CK, negatively impacted winter wheat growth. As a result, winter wheat in ECTI suffered from low temperature hazards during critical period of floret development and anthesis and grain number per ear was reduced by 10-31% in the three years. Although 1000-kernel weight in ECTI increased by 8-9% mainly due to elevated CO2, increasing CO2 concentration from 400 to 600 µmol mol-1 throughout the growth stage was not able to offset the adverse effect of warming on winter wheat growth and yield.

Infrared warming reduced winter wheat yields and some physiological parameters, which were mitigated by irrigation and worsened by delayed sowing.

Winter wheat has a central role in ensuring the food security and welfare of 1.3 billion people in China. Extensive previous studies have concluded that winter wheat yields would decrease with higher temperatures, owing to warming-induced soil drying or shortening of phenophase. Temperature in China is predicted to increase by 1-5°C by 2100, which may greatly impact plant production and cause other negative effects. We performed a manipulative field experiment, creating diverse growth regimes for wheat by infrared radiation (IR) warming day and night, including IR warming only (DW), IR warming + delayed sowing dates (DS), IR warming + increased irrigation (IW), and a control (CK). The results show that IR warming increased daily average wheat canopy and soil temperatures by 2.0°C and 2.3°C, respectively. DW was associated with an advanced maturity of 10 days and yield reduction of 8.2%. IR-warming effects on the photosynthetic apparatus of wheat varied with season as well as significant differences were found in the booting stage. DS represented a worsened situation, lowering yield per plant by 16.4%, with a significant decline in aboveground biomass and functional leaf area. Wheat under DS showed double-peak patterns of diurnal gas exchange during booting stages and, consequently, lower photosynthetic capacity with high transpiration for cooling. Significantly lower actual water use efficiency and intrinsic water use efficiency from jointing to anthesis stages were also found under DS. However, IW had no significant difference from CK, irrespective of yield and photosynthesis. Therefore, we concluded that delayed sowing date may not be a good choice for winter wheat, whereas a thoroughly-watered wheat agroecosystem should be promoted in the context of global warming.