Polygonum sibiricum polysaccharides exert the antidepressant-like effects in chronic unpredictable mild stress-induced depressive mice by modulating microbiota-gut-brain axis.

Polygonum sibiricum polysaccharides (PSP) are one of the main active components of Polygonatum sibiricum, which is a traditional Chinese medicine with food and drug homologies. Recent studies have revealed the antidepressant-like effects of PSP. However, the precise mechanisms have not been clarified. Therefore, the present study was conducted to explore that whether PSP could exert the antidepressant-like effects via microbiota-gut-brain (MGB) axis in chronic unpredictable mild stress (CUMS)-induced depressive mice by transplantation of fecal microbiota (FMT) from PSP administration mice. FMT markedly reversed the depressive-like behaviors of CUMS-induced mice in the open field, the sucrose preference, the tail suspension, the forced swimming, and the novelty-suppressed feeding tests. FMT significantly increased the levels of 5-hydroxytryptamine and norepinephrine, decreased the levels of the pro-inflammatory cytokines in the hippocampus and reduced the levels of corticosterone, an adrenocorticotropic-hormone, in the serum of CUMS-induced mice. In addition, administration of PSP and FMT significantly increased the expressions of ZO-1 and occludin in the colon and decreased the levels of lipopolysaccharide and interferon-γ in the serum of CUMS-induced mice. Moreover, administration of PSP and FMT regulated the signaling pathways of PI3K/AKT/TLR4/NF-κB and ERK/CREB/BDNF. Taken together, these findings indicated that PSP exerted antidepressant-like effects via the MGB axis.

Tenuifolin ameliorates the sleep deprivation-induced cognitive deficits.

Tenuifolin (TEN), a natural neuroprotective compound obtained from the Polygala tenuifolia Willd plant, has improved cognitive symptoms. However, the impact of TEN on memory impairments caused by sleep deprivation (SD) is unclear. Accordingly, the objective of this study was to investigate the mechanisms behind the preventative benefits of TEN on cognitive impairment caused by SD. TEN (10 and 20 mg/kg) and Huperzine A (0.1 mg/kg) were given to mice through oral gavage for 28 days during the SD process. The results indicate that TEN administrations improve short- and long-term memory impairments caused by SD in the Y-maze, object identification, and step-through tests. Moreover, TEN stimulated the generation of anti-inflammatory cytokines (interleukin-10), lowered the production of pro-inflammatory cytokines (interleukin-1ß, interleukin-6, and interleukin-18), and activated microglia, improving antioxidant status in the hippocampus. TEN treatments significantly boosted the expression of nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 while considerably decreasing the expression of NOD-like receptor thermal protein domain associated protein 3 and caspase-1 p20. Additionally, TEN restored the downregulation of the brain-derived neurotrophic factor signaling cascade and the impaired hippocampal neurogenesis induced by SD. When considered collectively, our data suggest that TEN is a potentially effective neuroprotective agent for cognition dysfunction.

[Spatio-temporal distribution of TN and TP in water and evaluation of eutrophic state of Lake Nansi].

Based on the seasonally investigating data from Lake Nansi during 2010 to 2011, the spatial and temporal distribution characteristics of total nitrogen (TN) and total phosphorus (TP) in water were analyzed, and the trophic state was also assessed. The results showed that the average concentrations of TN and TP were 2.617 mg x L(-1) and 0.110 mg x L(-1) respectively. The spatial variations of TN and TP in water were significantly different in four lake regions with the highest value of two parameters (3.830 mg x L(-1) and 0.192 mg x L(-1) respectively) were all found in Lake Nanyang while the lowest value in Lake Dushan (2.106 mg x L(-1)) and Lake Weishan (0.067 mg x L(-1)) respectively. Seasonally, the concentrations of TN in Lake Nansi had no significant difference, but the concentrations of TN in summer (2.805 mg x L(-1)) and spring (3.049 mg x L(-1)) were obviously higher than that in autumn (2.160 mg x L(-1)) and winter (2.452 mg x L(-1)), and that in four lake regions showed no uniform variation trends. While the seasonal change of the concentrations of TP in water were significantly different not only in Lake Nansi but also in its four lake regions, the variation trends were uniform with summer > spring > autumn > winter. Generally, the water quality of Lake Nansi has reached light eutrophication, among which, Lake Nanyang was in middle eutrophic state, while other three lake regions were in light eutrophic state. Integrated analysis indicted that external pollution was still the main influence factors of water quality in Lake Nansi, meanwhile, the pollution caused by pen fish culture was urgent for the control of non-point pollution sources.