Baicalin exerts neuroprotective effects via inhibiting activation of GSK3ß/NF-κB/NLRP3 signal pathway in a rat model of depression.

Chronic stress can provoke depressive-like behaviors through activation of inflammation and apoptosis, leading to a reduction of neurons. Antidepressant therapy may contribute to inhibiting inflammation responses and have neuroprotective effects. Baicalin (BA) has an antidepressant effect in the chronic unpredictable mild stress (CUMS) animal model and exerts anti-inflammation, anti-apoptosis, as well as neuroprotective effects in many central nervous system (CNS)-related diseases. But the effects of BA on neuroprotection, apoptosis, and neuroinflammation and the potential mechanisms in depression are unclear. Here, we focused on examining the therapeutic effects of BA in CUMS-induced depression rats and investigating the molecular mechanisms. Results showed that administration of BA improved depressive-like behaviors and significantly increased the levels of doublecortin (DCX), Neuron-specific enolase (NSE), and Brain-derived neurotrophic factor (BDNF) in hippocampus. Furthermore, administration of BA increased the cell survival by reducing the level of malondialdehyde (MDA) and increasing the level of superoxide dismutase (SOD). Finally, administration of BA significantly decreased CUMS-induced apoptosis and inflammatory cytokines (caspase-1 and IL-1ß) in hippocampus. These responses were mediated by Glycogen synthase kinase-3 (GSK3) ß/Nuclear factor-κB (NF-κB)/Nucleotide-binding domain, leucine-rich repeat, pyrin domain containing protein 3 (NLRP3) signal pathway. Taken together, these results indicate that BA could promote neuronal maturation and rescue neurons from apoptosis via inhibiting activation of GSK3ß/NF-κB/NLRP3 signal pathway that is known to be associated with inflammation, thus exerting neuroprotective effects and preventing CUMS-induced depressive-like behaviors.

[Vertical variability of Pinus sylvestris var. mongolica tree ring delta13C and its relationship with tree ring width in northern Daxing' an Mountains of Northeast China].

A measurement was made on the vertical direction tree ring stable carbon isotope ratio (delta13C) and tree ring width of Pinus sylvestris var. mongolica in northern Daxing' an Mountains of Northeast China, with the relationship between the vertical direction variations of the tree ring delta13C and tree ring width analyzed. In the whole ring of xylem, earlywood (EW) and bark endodermis, the delta13C all exhibited an increasing trend from the top to the base at first, with the maximum at the bottom of tree crown, and then, decreased rapidly to the minimum downward. The EW and late-wood (LW) had an increasing ratio of average tree ring width from the base to the top. The average annual sequence of the delta13C in vertical direction had an obvious reverse correspondence with the average annual sequence of tree ring width, and had a trend comparatively in line with the average annual sequence of the tree ring width ratio of EW to LW above tree crown. The variance analysis showed that there existed significant differences in the sequences of tree ring delta13C and ring width in vertical direction, and the magnitude of vertical delta13C variability was basically the same as that of the inter-annual delta13C variability. The year-to-year variation trend of the vertical delta13C sequence was approximately identical. For each sample, the delta13C sequence at the same heights was negatively correlated with the ring width sequence, but the statistical significance differed with tree height.