Hypothalamic Hnscr regulates glucose balance by mediating central inflammation and insulin signal.

OBJECTIVES: Hypothalamic dysfunction leads to glucose metabolic imbalance; however, the mechanisms still need clarification. Our current study was to explore the role of hypothalamic Hnscr in glucose metabolism. MATERIALS AND METHODS: Using Hnscr knockout or htNSC-specific Hnscr overexpression mice, we evaluated the effects of Hnscr on glucose metabolism through GTTs, ITTs, serum indicator measurements, etc. Immunofluorescence staining and Western blotting were performed to test inflammation levels and insulin signalling in hypothalamus. Conditioned medium intervene were used to investigate the effects of htNSCs on neuronal cell line. We also detected the glucose metabolism of mice with htNSCs implantation. RESULTS: Hnscr expression decreased in the hypothalamus after high-fat diet feed. Hnscr-null mice displayed aggravated systematic insulin resistance, while mice with htNSC-specific Hnscr overexpression had the opposite phenotype. Notably, Hnscr-null mice had increased NF-κB signal in htNSCs, along with enhanced inflammation and damaged insulin signal in neurons located in arcuate nucleus of hypothalamus. The secretions, including sEVs, of Hnscr-deficient htNSCs mediated the detrimental effects on the CNS cell line. Locally implantation with Hnscr-depleted htNSCs disrupted glucose homeostasis. CONCLUSIONS: This study demonstrated that decreased Hnscr in htNSCs led to systematic glucose imbalance through activating NF-κB signal and dampening insulin signal in hypothalamic neurons.

[Latitudinal variation in soil carbon, nitrogen and phosphorus pools across island forests and shrublands in eastern China]. / ä¸­å›½ä¸œéƒ¨æµ·å²›æ£®æž—å’ŒçŒä¸›åœŸå£¤ç¢³æ°®ç£·å »åˆ†åº“çš„çº¬åº¦å˜åŒ–.

Despite its monotonous structure, sea-island plays a crucial role in sustaining biodiversity and ecosystem functioning. The objectives of this study were to explore the altitudinal variation of soil carbon (C), nitrogen (N), and phosphorus (P) pools in forests across 14 islands spanning temperate zone (TZ), northern subtropical zone (NSZ), mid-subtropical zone (MSZ), and sou-thern subtropical zone (SSZ) in eastern China. The relationships of soil C and nutrient pools with climatic factors and plant species diversity were examined across islands. Our results showed that soil C, N and P pools differed significantly across climatic zones. Soil C and N pools were the lowest in TZ (49.35 and 1.08 t·hm-2) and the highest in NSZ (137.25 and 4.63 t·hm-2). Soil P pool was the lowest in SSZ (1.3 t·hm-2) and the highest in NSZ (5.19 t·hm-2). There were significant difference in soil C, N and P pools among vegetation types. Soil C, N and P pools in deciduous forests were significantly higher in subtropical than in temperate islands. Soil C and N pools in evergreen broadleaved forests did not differ among sub-climatic zones, and soil P pool was lower in SSZ than that in NSZ and MSZ. The interactions across mean annual temperature, mean annual precipitation, soil water content, and plant species diversity positively affected latitudinal variation in soil C, N, and P pools. Plant species diversity positively associated with soil N pool, but negatively linked with soil P pool. In conclusion, the latitudinal trend of soil C pool is different, but that of soil N and P pools are identical between sea-island and mainland. The main abiotic and biotic dri-vers of soil C, N and P pools are water availability, temperature and plant species diversity across sea-islands in eastern China.

Dendrobium officinale polysaccharides regulate age-related lineage commitment between osteogenic and adipogenic differentiation.

OBJECTIVES: Excessive oxidative stress and diminished antioxidant defences could contribute to age-related tissue damage and various diseases including age-related osteoporosis. Dendrobium officinale polysaccharides (DOPs), a major ingredient from a traditional Chinese medicine, have a great potential of antioxidative activity. In this study, we explore the role of DOP in age-related osteoporosis that remains elusive. MATERIALS AND METHODS: Oxidative stimulation and DOP were used to treat bone marrow mesenchymal stem cells (BMSCs), whose lineage commitment was measured by adipogenic- and osteoblastic-induced differentiation analysis. The oxidative stress and antioxidant capacity of BMSCs under the treatment of DOP were analysed by the level of MDA, SOD. Related mechanism studies were confirmed by qRT-PCR, Western blotting and siRNA transfection. DOP was orally administrated in aged mice whose phenotype was confirmed by micro-CT, immunofluorescence, immunochemistry and calcein double-labelling analysis. RESULTS: Dendrobium officinale polysaccharide treatment markedly increased osteogenic differentiation of BMSCs, while inhibiting adipogenic differentiation. In vitro, DOP could rescue H2O2-induced switch of BMSCs differentiation fate. However, this effect was abolished in BMSCs when interfered with Nrf2 siRNA. Furthermore, administration of DOP to aged mice significantly increased the bone mass and reduced the marrow adipose tissue (MAT) accompanied with decreased oxidative stress of BMSCs. CONCLUSIONS: Our study reveals that DOP can attenuate bone loss and MAT accumulation through NRF2 antioxidant signalling, which may represent as potential therapeutic agent for age-related osteoporosis.

[Carbon, nitrogen and phosphorus stoichiometry of five common herbaceous species across islands in the Yellow Sea and the East China Sea.] / 中国东黄海海岛5种常见草本的碳氮磷化学计量特征.

Understanding variation of carbon (C), nitrogen (N) and phosphorus (P) stoichiometry in common plant species across islands along a latitude gradient is insightful to reveal the adaptation strategies of plant species to environmental changes. Five common herbaceous species including Artemisia argyi, Setaira viridis, Humulus japonicus, Ophiopog onjaponicus, and Oxalis corniculata were sampled in 125 plots across nine islands in Eastern China. C, N and P contents in leaves, stems, and roots of five plant species were measured, and their relationships with soil C, N and P contents as well as mean annual air temperature (MAT) and mean annual precipitation (MAP) were investigated. The results showed that the range of C, N and P contents in aboveground parts of five species across nine islands was 352.16-518.16, 10.81-34.43, 0.58-2.38 mg·g-1, while the range of C:N, N:P and C:P was 11.98-38.99, 4.67-27.47, 133.39-748.54, respectively. In terms of roots, the range of C, N and P contents of five species was 312.28-493.34, 9.26-23.27, 0.40-2.10 mg·g-1, while the range of C:N, N:P and C:P was 18.18-46.79, 8.53-37.38, 174.45-1120.40, respectively. With the increases of latitude, contents of N and P in aboveground parts increased, but N:P decreased. Relative to N content, P content showed higher variation and was largely dependent on environment. Climate factors explained 60% of the variation of N and P contents and N:P across nine islands. In contrast, N and P contents and N:P of roots were independent of latitude, with climatic factors only explained 6%-10% of their variations. The contribution of climatic factors and soil nutrients contributed to the variations of N and P contents differed between above ground parts and roots of five species. Soil N and P had significant effects on P content in roots. Soil P content was positively correlated to aboveground P content. Soil properties explained 37% of the variation in N and P contents of plant roots. Our results suggested that latitude-associated environment shifts were the main drivers of variation in N and P contents and N:P in aboveground parts, and soil nutrients especially affected variation in P in roots of five common plant species, when the effects of plant phylogeny was controlled.

Fungal endophyte-derived Fritillaria unibracteata var. wabuensis: diversity, antioxidant capacities in vitro and relations to phenolic, flavonoid or saponin compounds.

Diverse fungal endophytes are rich fungal resources for the production of an enormous quantity of natural products. In the present study, 53 fungal endophytes were isolated from the bulbs of Fritillaria unibracteata var. wabuensis (FUW). Of these, 49 strains were identified and grouped into 17 different taxa, and priority was conferred to the Fusarium genus. All fungal fermented filtrates displayed antioxidant activities. The DPPH activity, total antioxidant capacities (ABTS), reduction power (FRAP), total phenolic content (TPC), total flavonoid content (TFC) and total saponin content (TSC) were evaluated using petroleum ether, ethyl acetate, n-butyl alcohol and ethanol fractions extracted from five representative fungal cultures. The last three fractions showed more potent antioxidant activity than the first fraction. Significant positive correlations were found between the compositions (TPC, TFC and TSC) and antioxidant capacities (DPPH, ABTS and FRAP). In addition, multifarious natural antioxidant components were identified from the fungal extracts, including gallic acid, rutin, phlorizin, 2,4-di-tert-butylphenol and 2,6-di-tert-butyl hydroquinone; these were determined preliminarily by TLC-bioautography, HPLC and GC-MS analysis. This study showed abundant fungal resources in FUW. Phenolics, flavonoids and saponins are crucial bioactive constituents in these abundant fungal endophytes and can be viewed as new potential antioxidant resources.

[Advances on chemical constituents and bioactivities of genus Stellera].

Advance on chemical constituents and pharmacological activities of Stellera plants have been conducted. The chemical constituents include terpenes, coumarins, flavonoids, lignans, volatile oils, and other compounds. Pharmacological studies showed that diterpenoids and biflavones showed strong activities, such as antitumor, anti-HIV, and immune regulations. This review hopes to provide a scientific basis for further research and explorations of the medicinal values of the genus.