In light of global warming, the interaction between plant nutrient traits and soil nutrients is still unclear. Plant nutrient traits (e.g., N and P) and their stoichiometric relationships (N/P ratio) are essential for plant growth and reproduction. However, the specific role of soil nutrients in driving variation in plant nutrient traits remains poorly understood. Fifty natural Pinus tabuliformis forests were used as the research object to clarify the interaction between plant nutrient traits and soil nutrients. We show that: (1) The Nmass, Pmass and N/P ratios of leaves were significantly higher than those of roots. The N/P ratio of both leaves and roots was less than 14. (2) Leaf nutrient traits showed diverse relationship patterns with root nutrient traits throughout the growing period. Significant changes were found in root nutrient PC2 (the second principal component of root nutrient traits) and leaf nutrient PC1 (the first principal component of leaf traits), and non-significant changes were found in other relationships between leaf and root traits (p > 0.05). Root nutrient traits explained 36.4% of the variance in leaf nutrient traits. (3) With the increase in soil nutrient PC2 (related to N), leaf PC2 (related to N) showed a significant trend of first decreasing and then increasing (p < 0.05). Only the soil Nmass was significantly correlated with the leaf Nmass (p < 0.05), which demonstrated that the growth and survival of Pinus tabuliformis forests were mainly affected by N-limitation.
With global warming, the concentrations of fine particulate matter (PM2.5) and greenhouse gases, such as CO2, are increasing. However, it is still unknown whether these increases will affect vegetation productivity. Exploring the impacts of global warming on net primary productivity (NPP) will help us understand how ecosystem function responds to climate change in China. Using the Carnegie-Ames-Stanford Approach (CASA) ecosystem model based on remote sensing, we investigated the spatiotemporal changes in NPP across 1137 sites in China from 2001 to 2017. Our results revealed that: (1) Mean Annual Temperature (MAT) and Mean Annual Precipitation (MAP) were significantly positively correlated with NPP (p < 0.01), while PM2.5 concentration and CO2 emissions were significantly negatively correlated with NPP (p < 0.01). (2) The positive correlation between temperature, rainfall and NPP gradually weakened over time, while the negative correlation between PM2.5 concentration, CO2 emissions and NPP gradually strengthened over time. (3) High levels of PM2.5 concentration and CO2 emissions had negative effects on NPP, while high levels of MAT and MAP had positive effects on NPP.
Prunus cerasifera Ehrhart (P. cerasifera) flourishes uniquely in the arid landscapes of Xinjiang, China. Preliminary studies have revealed the therapeutic potential of its polyphenol extract (PPE) in mitigating liver lipid accumulation in mice fed a high-fat diet. We established a mouse model that was subjected to a continuous high-fat diet for 24 weeks and administered PPE to investigate the effects of PPE on cholesterol and BA metabolism in NAFLD mice. The results showed that PPE administration (200 and 400 mg/kg/day, BW) led to a reduction in liver TC, an increase in liver T-BAs, and normalization of the disrupted fecal BA profile. Concurrently, it decreased levels of lipotoxic BAs and inhibited hepatic cholesterol synthesis (evidenced by reduced HMGCR activity) and intestinal cholesterol absorption (indicated by lower ACAT2 levels) while enhancing intestinal cholesterol efflux (via LXRα, ABCA1, ABCG5, and ABCG8) and stimulating hepatic BA synthesis (CYP7A1, CYP27A1) and secretion (BSEP). PPE thus led to a significant reduction in lipotoxic BAs metabolized by gut microbiota and a downregulation of the BA secretion pathway under its influence. Our findings reveal the therapeutic effect of PPE on NAFLD mice via regulating cholesterol and BA metabolism, providing a theoretical basis for exploring the potential functions of P. cerasifera.
Creatine (Cr) is a widely utilized nutritional supplement. Empirical evidence indicates that Cr supplementation significantly elevates intramuscular Cr content, thereby providing an energy substrate reservoir for exercise performance and facilitating improvements in muscle strength. Although numerous studies have examined the relationship between Cr and muscle strength, comprehensive investigations into population-specific ergogenic responses, optimal Cr dosage, and concomitant training intensity remain limited. These parameters are critical determinants for maximizing the efficacy of Cr supplementation. Against this backdrop, this study adopts meta-analysis, integrating conventional and Robust Variance Estimation (RVE) models, to comprehensively evaluate the intervention effects of Cr supplementation across three dimensions: population applicability, dosage optimization, and training intensity (PROSPERO registration number: CRD42024547697). It aims to provide evidence-based support for precise clinical application and subsequent research directions. Results: Results showed no statistical difference in baseline muscle strength between the Cr intervention group and the control group; after intervention, the Cr group exhibited significant strength gains. Further subgroup analysis revealed: untrained individuals had greater muscle strength improvements than trained ones; the low-to-moderate dose group showed better effects than the high-dose group; high-intensity training had more significant effect sizes than low-intensity training; and no definitive conclusion was reached on muscle strength improvements between middle-aged/elderly and young populations. Conclusion: Cr supplementation significantly improves muscle strength in the general population. Specifically: untrained individuals show greater muscle strength improvements; low-dose supplementation combined with high-intensity exercise yields better effects; no definitive conclusion was reached on effect differences between middle-aged/elderly and young populations, requiring larger-sample studies for more precise effect size analysis.