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31.
Serpinb6b is a novel member of Serpinb family and found in germ and somatic cells of mouse gonads, but its physiological function in uterine decidualization remains unclear. The present study revealed that abundant Serpinb6b was noted in decidual cells, and advanced the proliferation and differentiation of stromal cells, indicating a creative role of Serpinb6b in uterine decidualization. Further analysis found that Serpinb6b modulated the expression of Mmp2 and Mmp9. Meanwhile, Serpinb6b was identified as a target of Bmp2 regulation in stromal differentiation. Treatment with rBmp2 resulted in an accumulation of intracellular cAMP level whose function in this differentiation program was mediated by Serpinb6b. Addition of PKA inhibitor H89 impeded the Bmp2 induction of Serpinb6b, whereas 8‐Br‐cAMP rescued the defect of Serpinb6b expression elicited by Bmp2 knock‐down. Attenuation of Serpinb6b greatly reduced the induction of constitutive Wnt4 activation on stromal cell differentiation. By contrast, overexpression of Serpinb6b prevented this inhibition of differentiation process by Wnt4 siRNA. Moreover, blockage of Wnt4 abrogated the up‐regulation of cAMP on Serpinb6b. Collectively, Serpinb6b mediates uterine decidualization via Mmp2/9 in response to Bmp2/cAMP/PKA/Wnt4 pathway.  相似文献   
32.
Leptin is well acknowledged as an anorexigenic hormone that plays an important role in feeding control. Hypothalamic GABA system plays a significant role in leptin regulation on feeding and metabolism control. However, the pharmacological relationship of leptin and GABA receptor is still obscure. Therefore, we investigated the effect of leptin or combined with baclofen on the food intake in fasted mice. We detected the changes in hypothalamic c‐Fos expression, hypothalamic TH, POMC and GAD67 expression, plasma insulin, POMC and GABA levels to demonstrate the mechanisms. We found that leptin inhibit fasting‐induced increased food intake and activated hypothalamic neurons. The inhibitory effect on food intake induced by leptin in fasted mice can be reversed by pretreatment with baclofen. Baclofen reversed leptin's inhibition on c‐Fos expression of PAMM in fasted mice. Therefore, these results indicate that leptin might inhibit fasting‐triggered activation of PVN neurons via presynaptic GABA synaptic functions which might be partially blocked by pharmacological activating GABA‐B. Our findings identify the role of leptin in the regulation of food intake.  相似文献   
33.
本研究检测了40例食管癌组织和40例癌旁组织中的miR-21、PTEN、PI3K和AKT表达,并通过转染miR-21抑制剂来敲低人食管癌细胞系EC9706的miR-21表达,考察了miR-21对食管癌细胞生长的影响。研究发现,食管癌组织中PTEN蛋白的阳性染色评分低于癌旁组织(p<0.05),而PI3K和AKT蛋白的阳性染色评分高于癌旁组织(p<0.05)。miR-21在人食管癌组织中被上调(3.56 vs 1.21,p<0.05)。转染miR-21抑制剂导致PTEN蛋白表达升高,而PI3K和AKT蛋白表达降低(p<0.05)。转染miR-21抑制剂抑制了EC9706细胞的增殖和迁移,但促进了细胞凋亡(p<0.05)。miR-21的上调可通过激活PTEN/PI3K/AKT信号通路来促进食道癌细胞的增殖和迁移,并抑制细胞凋亡。  相似文献   
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Wu  Xiao-Han  Fan  Ming-Zhi  Li  Xue-Feng  Piao  Xuan-Chun  Gao  Ri  Lian  Mei-Lan 《Journal of Plant Growth Regulation》2021,40(4):1440-1449
Journal of Plant Growth Regulation - The adventitious root (AR) culture of Panax ginseng C.A. Meyer is an alternative route for mass production of ginsenosides. During the AR culture of P. ginseng,...  相似文献   
36.
Growth rate and energy reserves are important determinants of fitness and are governed by endogenous and exogenous factors. Thus, examining the influence of individual and multiple stressors on growth and energy reserves can help estimate population health under current and future conditions. In young anadromous fishes, freshwater habitat quality determines physiological state and fitness of juveniles emigrating to marine habitats. In this study, the authors tested how temperature and food availability affect survival, growth and energy reserves in juvenile anadromous alewives (Alosa pseudoharengus), a forage fish distributed along the eastern North American continent. Field-collected juvenile anadromous A. pseudoharengus were exposed for 21 days to one of two temperatures (21°C and 25°C) and one of two levels of food rations (1% or 2% tank biomass daily) and compared for differences in final size, fat mass-at-length, lean mass-at-length and energy density. Increased temperature and reduced ration both led to lower growth rates, and the effect of reduced ration was greater at higher temperature. Fat mass-at-length decreased with dry mass, and energy density increased with total length, suggesting size-based endogenous influences on energy reserves. Lower ration also directly decreased fat mass-at-length, lean mass-at-length and energy density. Given the fitness implications of size and energy reserves, temperature and food availability should be considered important indicators of nursery habitat quality and incorporated in A. pseudoharengus life-history models to improve forecasting of population health under climate change.  相似文献   
37.
Chen  Jiakui  Li  Gaofei  Lian  Junwei  Ma  Ning  Huang  Zhibin  Li  Jianchao  Wen  Zilong  Zhang  Wenqing  Zhang  Yiyue 《中国科学:生命科学英文版》2021,64(12):2186-2201
Science China Life Sciences - Hematopoietic stem and progenitor cells (HSPCs) are able to self-renew and can give rise to all blood lineages throughout their lifetime, yet the mechanisms regulating...  相似文献   
38.
The discovery of threosyl phosphonate nucleoside (PMDTA, EC50 = 2.53 μM) as a potent anti-HIV agent has led to the synthesis and biological evaluation of 5 ′-deoxyversions of threosyl phosphonate nucleosides from 1,4-dihydroxy-2-butene. The synthesized nucleoside phosphonic acid analogues 14 and 19 were tested for anti-HIV activity as well as cytotoxicity. The adenine analogue 14 exhibits moderate in vitro anti-HIV-1 activity (EC50 = 12.6 μM).  相似文献   
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Cardiomyocyte apoptosis is a common pathological alteration in heart disease which results in systolic dysfunction or sudden death. Klotho is a novel anti-aging hormone. We tested the effects of klotho on cell apoptosis in isoproterenol-treated cardiomyocytes. In BALB/c mice, cardiac injury was induced by subcutaneous injection of isoproterenol (5mg/kg, for 9days, sc). Klotho (0.01 mg/kg, every other day for 4days, ip) was administered to determine the changes in isoproterenol-induced apoptosis. Mouse heart was harvested at day 2, day 5, and day 9 after isoproterenol injection. Isoproterenol induced cardiac apoptosis and endoplasmic reticulum (ER) stress in a time-dependent manner. However, klotho partly reversed isoproterenol-induced cardiac apoptosis and ER stress. These same effects were observed in cultured cardiomyocytes. Furthermore, the results also showed that SB203580, a p38 inhibitor, and SP600125, a c-Jun NH2-terminal kinase (JNK) inhibitor, reduced cardiomyocyte apoptosis and ER stress, however, klotho suppressed isoproterenol-induced activation of p38 and JNK. Taken together, these results indicated that cardioprotection by klotho was related to the attenuation of ER stress and ER stress-induced apoptosis, at least partly, through suppressing activation of the p38 and JNK pathway.  相似文献   
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