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Xiaojing Meng Lingxiao Yue An Liu Wenjuan Tao Li Shi Wan Zhao Zhongmin Wu Zhi Zhang Liecheng Wang Xulai Zhang Wenjie Zhou 《The Journal of biological chemistry》2022,298(8)
Pain is a multidimensional perception that includes unpleasant somatosensory and affective experiences; however, the underlying neural circuits that mediate different components of pain remain elusive. Although hyperactivity of basolateral amygdala glutamatergic (BLAGlu) neurons is required for the somatosensory and emotional processing of pain, the precise excitatory inputs to BLAGlu neurons and their roles in mediating different aspects of pain are unclear. Here, we identified two discrete glutamatergic neuronal circuits in male mice: a projection from the insular cortex glutamatergic (ICGlu) to BLAGlu neurons, which modulates both the somatosensory and affective components of pain, and a projection from the mediodorsal thalamic nucleus (MDGlu) to BLAGlu neurons, which modulates only the aversive-affective component of pain. Using whole-cell recording and fiber photometry, we found that neurons within the IC→BLA and MD→BLA pathways were activated in mice upon inflammatory pain induced by injection of complete Freund’s adjuvant (CFA) into their paws. Optical inhibition of the ICGlu→BLA pathway increased the nociceptive threshold and induced behavioral place preference in CFA mice. In contrast, optical inhibition of the MDGlu→BLA pathway did not affect the nociceptive threshold but still induced place preference in CFA mice. In normal mice, optical activation of the ICGlu→BLA pathway decreased the nociceptive threshold and induced place aversion, while optical activation of the MDGlu→BLA pathway only evoked aversion. Taken together, our results demonstrate that discrete ICGlu→BLA and MDGlu→BLA pathways are involved in modulating different components of pain, provide insights into its circuit basis, and better our understanding of pain perception. 相似文献
114.
叶绿体基因组编码许多参与光合作用和其他代谢过程的关键蛋白质,在叶绿体中合成的代谢物对于植物正常的生长发育至关重要。根对紫外线-B辐射敏感[Root-UVB (ultraviolet radiation B)-sensitive, RUS]蛋白属于叶绿体蛋白,由高度保守的DUF647结构域组成,在参与植物形态发生、物质运输和能量代谢等多种生命活动的调控中发挥作用。本文就近年来关于RUS家族在植物的胚胎发育、光形态建成、维生素B6稳态、生长素转运和花药发育等生长发育过程中的相关研究进行回顾和总结,为深入研究其在植物生长发育中的分子调控机制提供了参考。 相似文献
115.
Lihua Qu Yi Li Chao Chen Tong Yin Qian Fang Yijin Zhao Wenting Lv Ziqi Liu Yangye Chen Li Shen 《Cell death & disease》2022,13(8)
Acute lung injury (ALI) is a potentially life-threatening, devastating disease with an extremely high rate of mortality. The underlying mechanism of ALI is currently unclear. In this study, we aimed to confirm the hub genes associated with ALI and explore their functions and molecular mechanisms using bioinformatics methods. Five microarray datasets available in GEO were used to perform Robust Rank Aggregation (RRA) to identify differentially expressed genes (DEGs) and the key genes were identified via the protein-protein interaction (PPI) network. Lipopolysaccharide intraperitoneal injection was administered to establish an ALI model. Overall, 40 robust DEGs, which are mainly involved in the inflammatory response, protein catabolic process, and NF-κB signaling pathway were identified. Among these DEGs, we identified two genes associated with ALI, of which the CAV-1/NF-κB axis was significantly upregulated in ALI, and was identified as one of the most effective targets for ALI prevention. Subsequently, the expression of CAV-1 was knocked down using AAV-shCAV-1 or CAV-1-siRNA to study its effect on the pathogenesis of ALI in vivo and in vitro. The results of this study indicated that CAV-1/NF-κB axis levels were elevated in vivo and in vitro, accompanied by an increase in lung inflammation and autophagy. The knockdown of CAV-1 may improve ALI. Mechanistically, inflammation was reduced mainly by decreasing the expression levels of CD3 and F4/80, and activating autophagy by inhibiting AKT/mTOR and promoting the AMPK signaling pathway. Taken together, this study provides crucial evidence that CAV-1 knockdown inhibits the occurrence of ALI, suggesting that the CAV-1/NF-κB axis may be a promising therapeutic target for ALI treatment.Subject terms: Cell signalling, Respiratory tract diseases 相似文献
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Han Mo Linghan Wang Yuting Chen Xuchen Zhang Ning Huang Tingting Liu Wantong Hu Yi Zhong Qian Li 《Aging cell》2022,21(6)
Age‐related memory impairment (AMI) is a common phenomenon across species. Vulnerability to interfering stimuli has been proposed to be an important cause of AMI. However, the molecular mechanisms underlying this vulnerability‐related AMI remain unknown. Here we show that learning‐activated MAPK signals are gradually lost with age, leading to vulnerability‐related AMI in Drosophila. Young flies (2‐ or 3‐day‐old) exhibited a significant increase in phosphorylated MAPK levels within 15 min after learning, whereas aged flies (25‐day‐old) did not. Compared to 3‐day‐old flies, significant 1 h memory impairments were observed in 15‐, 20‐, and 30‐day‐old flies, but not in 10‐day‐old flies. However, with post‐learning interfering stimuli such as cooling or electric stimuli, 10‐day‐old flies had worse memory performance at 1 h than 3‐day‐old flies, showing a premature AMI phenomenon. Increasing learning‐activated MAPK signals through acute transgene expression in mushroom body (MB) neurons restored physiological trace of 1 h memory in a pair of MB output neurons in aged flies. Decreasing such signals in young flies mimicked the impairment of 1 h memory trace in aged flies. Restoring learning‐activated MAPK signals in MB neurons in aged flies significantly suppressed AMI even with interfering stimuli. Thus, our data suggest that age‐related loss of learning‐activated neuronal MAPK signals causes memory vulnerability to interfering stimuli, thereby leading to AMI. 相似文献
118.
LRG‐1 promotes fat graft survival through the RAB31‐mediated inhibition of hypoxia‐induced apoptosis
Chiakang Ho Danning Zheng Jiaming Sun Dongsheng Wen Shan Wu Li Yu Ya Gao Yifan Zhang Qingfeng Li 《Journal of cellular and molecular medicine》2022,26(11):3153
Autologous adipose tissue is an ideal soft tissue filling material, and its biocompatibility is better than that of artificial tissue substitutes, foreign bodies and heterogeneous materials. Although autologous fat transplantation has many advantages, the low retention rate of adipose tissue limits its clinical application. Here, we identified a secretory glycoprotein, leucine‐rich‐alpha‐2‐glycoprotein 1 (LRG‐1), that could promote fat graft survival through RAB31‐mediated inhibition of hypoxia‐induced apoptosis. We showed that LRG‐1 injection significantly increased the maintenance of fat volume and weight compared with the control. In addition, higher fat integrity, more viable adipocytes and fewer apoptotic cells were observed in the LRG‐1‐treated groups. Furthermore, we discovered that LRG‐1 could reduce the ADSC apoptosis induced by hypoxic conditions. The mechanism underlying the LRG‐1‐mediated suppression of the ADSC apoptosis induced by hypoxia was mediated by the upregulation of RAB31 expression. Using LRG‐1 for fat grafts may prove to be clinically successful for increasing the retention rate of transplanted fat. 相似文献
119.
Ennian Li Kai Wang Bei Zhang Siqi Guo Senhao Xiao Qi Pan Xiaowan Wang Weiying Chen Yunshan Wu Hesong Xu Xiangqian Kong Cheng Luo Shijie Chen Bo Liu 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1537
The DNA methyltransferases (DNMTs) were found in mammals to maintain DNA methylation. Among them, DNMT1 was the first identified, and it is an attractive target for tumour chemotherapy. DC_05 and DC_517 have been reported in our previous work, which is non-nucleoside DNMT1 inhibitor with low micromolar IC50 values and significant selectivity towards other S-adenosyl-L-methionine (SAM)-dependent protein methyltransferases. In this study, through a process of similarity-based analog searching, a series of DNMT1 inhibitors were designed, synthesized, and evaluated as anticancer agents. SAR studies were conducted based on enzymatic assays. And most of the compounds showed strong inhibitory activity on human DNMT1, especially WK-23 displayed a good inhibitory effect on human DNMT1 with an IC50 value of 5.0 µM. Importantly, the pharmacokinetic (PK) profile of WK-23 was obtained with quite satisfying oral bioavailability and elimination half-life. Taken together, WK-23 is worth developing as DNMT1-selective therapy for the treatment of malignant tumour. 相似文献
120.
谭清苏铁性别相关的RAPD标记研究 总被引:1,自引:0,他引:1
以谭清苏铁(Cycas tanqingii D.Y.Wang)雌雄植株半年生羽叶为材料,用优化的CTAB法分别提取其全基因组DNA,进行RAPD单因子梯度实验和正交实验以优化扩增条件。应用160个RAPD随机引物检测基因组DNA,雌雄植株均扩增出1450多条带,其中引物S0465扩增出与谭清苏铁雌株高度相关的RAPD标记,其大小约为500bp,该标记与雄株没有关联。 相似文献