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In order to explore the adaptive changes in energy metabolism and body composition in response to a gradual reduction in both ambient temperature and photoperiod, male adult tree shrews Tupaia belangeri chinensis were raised under the conditions of 30 oC and 12L:12D photoperiod (control group). The treatment group was changed from 25 oC and 16L:8D photoperiod to 5 oC and 8L:16D photoperiod (treatment group) over a period of four weeks and then maintained at those conditions for a further 4 weeks. Changes in body mass, resting metabolic rates (RMR),energy intake, and wet and dry mass of organs and tissues were measured at the end of the acclimation. Body mass in treatment tree shrews was higher than control. RMR showed significant differences between groups. No significant differences were detected in dry matter intake, energy intake, and digestible energy intake in control tree shrews during the whole acclimation period, while these parameters were significantly increased within treatment tree shrews at the end of acclimation, and were significantly higher than those in control tree shrews. Small intestine and stomach dry mass, as well as the wet mass of small intestine, heart, lung, liver and kidney were significantly higher in treatment groups than in controls, but no significant differences were found in the mass of other organs and tissues. These results suggest that increasing body mass and energy intake, together with adjusting the mass of some organs and tissues, are important physiological changes in tree shrews to adapt the changing environmental conditions.

As a major risk factor for cardiovascular diseases (CVD), Obstructive sleep apnea (OSA) is characterized by chronic intermittent hypoxia (CIH). Recent studies indicated that the increased cardiovascular risk in patients with OSA may be mediated by accelerated vascular senescence. Danggui-Buxue decoction (DBD) has been used for treating cardiovascular diseases, but its mechanism of vascular senescence regulation is still unclear. To investigate the effect of DBD on vascular senescence in mice exposed to CIH and to explore the role of the Nrf2/HO-1 pathway. C57BL/6N mice were randomly divided into Normoxia control group (CON), CIH (21%-5% O2, 20 times/h, 8 h/d) exposed group (CIH), and DBD treatment group (intragastrically treated with 2.34, 4.68, or 9.36 g/kg/day of DBD separately for 12 weeks as DBL, DBM, or DBH). Blood pressure, cardiac and vascular function, vascular senescence, inflammation response, oxidative stress, and Nrf2/HO-1 expression were determined. DBD (4.68 and 9.36 g/kg) significantly decreased Tail-cuff blood pressure, increased left ventricular systolic function, and alleviated arterial stiffness and vasorelaxation dysfunction in mice exposed to CIH. DBD treatment reduced SA-β-gal activity, decreased p16 (0.68-fold, 0.62-fold), P21 (0.58-fold, 0.52-fold), and p53 expressions (0.67-fold, 0.65-fold), and increased SIRT1 expression (2.22-fold, 2.98-fold) in the aortic. DBD treatment decreased IL-6, NF-κB, and TNF-α expressions, decreased MDA but increased SOD levels, and increased Nrf2 (1.8-fold, 1.89-fold) and HO-1 (2.25-fold, 2.43-fold) expression. DBD could attenuate vascular senescence accelerated by CIH exposure through inhibiting inflammatory response and oxidative stress by activating the Nrf2/HO-1 pathway. [ABSTRACT FROM AUTHOR]

Triptolide and fenofibrate are often used together for the treatment of nephrotic syndrome in Chinese clinics. This study investigates the effects of triptolide on the pharmacokinetics of fenofibrate in rats and it potential mechanism. The pharmacokinetics of fenofibrate (20 mg/kg) with or without triptolide pretreatment (2 mg/kg/day for seven days) were investigated. Additionally, the inhibitory effects of triptolide on the metabolic stability of fenofibrate were investigated using rat liver microsome incubation systems. The results indicated that the Cmax (35.34 ± 7.52 vs. 30.43 ± 6.45 μg/mL), t1/2 (6.17 ± 1.15 vs. 4.90 ± 0.82 h) and AUC(0-t) (468.12 ± 35.84 vs. 416.35 ± 32.68 mg h L−1) of fenofibric acid decreased significantly (p < .05). The Tmax of fenofibric acid increased significantly (p < .05) from 5.12 ± 0.36 to 6.07 ± 0.68 h. Additionally, the metabolic stability of fenofibrate was prolonged from 35.8 ± 6.2 to 48.6 ± 7.5 min (p < .05) with the pretreatment of triptolide. In conclusion, these results indicated that triptolide could affect the pharmacokinetics of fenofibric acid, possibly by inhibiting the metabolism of fenofibrate in rat liver when they were co-administered. [ABSTRACT FROM AUTHOR]

In this study, we compared stand structure, biomass and soil carbon pools, and litterfall production between a mixed mangrove forest consisting of Aegiceras corniculatum inter-planted with the exotic Sonneratia apetala and a native monospecific forest dominated by A. corniculatum in the intertidal area of Zhanjiang, Guangdong Province, southeast China. The goal of this study was to test the hypothesis that inter-planting fast growing exotic mangrove S. apetala into subtropical native mangrove forests will significantly increase C sequestration. Although the tree heights and basal diameters of S. apetala were significantly higher than those of A. corniculatum, the density of the 12-year-old S. apetala trees in the mixed forest was much smaller than that of A. corniculatum in the monospecific forest. In contrast to several previous studies on S. apetala forests planted directly on mangrove-free mudflats, the mixed mangrove forest showed no significant difference in either standing biomass or soil carbon pools from the native monospecific mangrove forest (p = 0.294 and 0.073, respectively) twelve years after inter-planting with S. apetala. Moreover, carbon cycling was likely speeded up after inter-planting S. apetala due to higher litterfall input and lower C/N ratio. Thus, inter-planting fast-growing S. apetala into native mangrove forest is not an effective way to increase carbon sequestration in this subtropical mangrove forest. Given that exotic plant species may exert negative impact on native mangrove species and related epifauna, this fast-growing mangrove species is not suitable for mangrove plantation projects aiming mainly at enhancing carbon sequestration. [ABSTRACT FROM AUTHOR]