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51.
Yangyang Xu Jie Zhang Fei Gao Wenna Cheng Ye Zhang Chuanmei Wei Shuping Zhang Xinfu Gao 《Journal of cellular and molecular medicine》2023,27(12):1653-1663
High-mobility group box1 (HMGB1) induces inflammatory injury, and emerging reports suggest that it is critical for brain ischemia reperfusion. Engeletin, a natural Smilax glabra rhizomilax derivative, is reported to possess anti-inflammatory activity. Herein, we examined the mechanism of engeletin-mediated neuroprotection in rats having transient middle cerebral artery occlusion (tMCAO) against cerebral ischemia reperfusion injury. Male SD rats were induced using a 1.5 h tMCAO, following by reperfusion for 22.5 h. Engeletin (15, 30 or 60 mg/kg) was intravenously administered immediately following 0.5 h of ischemia. Based on our results, engeletin, in a dose-dependent fashion, reduced neurological deficits, infarct size, histopathological alterations, brain edema and inflammatory factors, namely, circulating IL-1β, TNF-α, IL-6 and IFN-γ. Furthermore, engeletin treatment markedly reduced neuronal apoptosis, which, in turn, elevated Bcl-2 protein levels, while suppressing Bax and Cleaved Caspase-3 protein levels. Meanwhile, engeletin significantly reduces overall expressions of HMGB1, TLR4, and NF-κB and attenuated nuclear transfer of nuclear factor kappa B (NF-κB) p65 in ischemic cortical tissue. In conclusion, engeletin strongly prevents focal cerebral ischemia via suppression of the HMGB1/TLR4/NF-κB inflammatory network. 相似文献
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53.
摘要 目的:探讨依达拉奉右莰醇联合丁苯酞对老年大动脉粥样硬化(LAA)型脑卒中患者血清五聚素3(PTX3)、脂蛋白相关磷脂酶A2(Lp-PLA2)以及微栓子信号(MES)的影响。方法:回顾性选取2021年9月-2022年9月在本院收治的120例老年LAA型脑卒中患者,根据其不同治疗方案分为对照组(56例),采用依达拉奉右莰醇单独治疗,和观察组(64例),采用依达拉奉右莰醇联合丁苯酞治疗。观察两组患者的临床疗效;对比两组患者治疗前后神经功能[脑卒中量表(NIHSS)及中枢神经特异性蛋白(S-100β)、神经元特异性烯醇化酶(NSE)]状态、炎症因子[血清五聚素3(PTX3)、脂蛋白相关磷脂酶A2(Lp-PLA2)]水平及脑血流微栓子信号(MES)阳性率变化。记录不良反应发生情况。结果:观察组患者治疗有效率为95.31%,高于对照组的78.57%(χ2=7.653 ,P=0.006);治疗后,观察组患者NIHSS评分、S-100β及NSE水平低于对照组(P<0.05);观察组PTX3、Lp-PLA2水平及MES阳性率低于对照组(P<0.05)。观察组与对照组总不良反应发生率比较无差异(6.25 % vs 5.36 %)(Fisher=1.000)。结论:依达拉奉右莰醇联合丁苯酞可有效提高临床疗效,促进老年LAA型患者神经功能恢复,降低PTX3、lp-PLA2水平及MES阳性率,控制病情发展,且安全性较好。 相似文献
54.
本文用PCR方法获得大肠杆菌热休克蛋白转录因子σ32的编码基因rpoH,并克隆在含有tac启动子的表达载体pUHE中,经IPTG诱导,在大肠杆菌中表达了C端融合有6个寡聚组氨酸的σ32。表达产物经金属螯合层析一步纯化,达到SDS-PAGE银染一条带纯度,氨基酸组成分析及N端序列分析结果与文献报道一致。35S细胞内参入实验表明:即使在较低的温度下,表达产物σ32(His)6也能导致热休克蛋白如GroEl、DnaK、Htp的大量合成. 相似文献
55.
56.
Cell signaling and heat shock protein expression 总被引:5,自引:0,他引:5
Exposure of cells and organs to heat shock is associated with numerous changes in various cellular metabolic parameters and overexpression of proteins collectively known as heat shock proteins (HSP). In this communication we review the cell-signaling events that are altered in response to heat shock as they relate to the subsequent induction of HSP 70 kd (HSP-70) expression. We also review the mechanisms by which HSP-70 is involved in conferring cytoprotective effects. The possibility of altering HSP expression through manipulations of the cell-signal process has clinical importance.The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or reflecting the views of the Department of the Army or Department of Defense. 相似文献
57.
Abstract: The combined effect of hydrostatic pressure and heat shock on thermotolerance was examined in the deep-sea hyperthermophilic archaeon Pyrococcus strain ES4. Pressure equivalent to the depth of isolation (22 MPa) enhanced ES4's survival at super-optimal temperatures (101–108°C) relative to low pressure (3 MPa). Pressure also raised the temperature at which a putative heat-shock protein (98 kDa) accumulated. ES4 grown at 95°C and 3 MPa displayed immediate enhanced thermotolerance to 105°C after being shifted to 22 MPa. Cultures grown at 95°C and 22 MPa and then heat shocked at 105°C and 3 MPa retained enhanced thermotolerance after decompression. These results suggest that this deep-sea hyperthermophile has developed pressure-induced responses that include increased survival to hyperthermal conditions. 相似文献
58.
Expression of heat shock genes in Clostridium acetobutylicum 总被引:1,自引:0,他引:1
59.
The ability to withstand thermal stress in a laboratory population of the blowflyLucilia cuprina (measured as per cent adult survival following varying periods of exposure to elevated temperature up to a maximum of 48°C)
was in the order pupa > larva > adult. Pre-exposure to a mild heat shock (37°C) induced tolerance to temperatures which were
otherwise lethal. An analysis of heat shock-induced protein synthesis during development at similar elevated temperatures
presented patterns corresponding to the above observations on thermotolerance. The induced level of synthesis of major heat
shock proteins (viz., 79, 69, 28, 20 and 19 kDa) were greater in larval tissues than in most of the adult tissues except gonads.
The response varied between young (2 days) and old (30 days) adults in a tissue-specific manner. In general, heat shock protein
69 kDa was most abundant in all the tissues studied. Control as well as heat shocked Malpighian tubules of adults uniquely
showed two major [35S]methionine labelled bands corresponding to approximately 62 and 64 kDa. Immunoblots showed the 62 kDa protein to cross react
with an antibody againstHelioihis HSP60. Although the synthesis of the 62 kDa polypeptide was prominent only in Malpighian tubules of adult blowflies, nearly
equal levels of this HSP60 family polypeptide were present in all tissues (control as well heat shocked) except the larval
salivary glands. 相似文献
60.
Irene Konstantopoulou Christos A. Ouzounis Elena Drosopoulou Minas Yiangou Paschalis Sideras Chris Sander Zacharias G. Scouras 《Journal of molecular evolution》1995,41(4):414-420
A clone isolated from a Drosophila auraria heat-shock cDNA library presents two long, antiparallel, coupled (LAC) open reading frames (ORFs). One strand ORF is 1,929 nucleotides long and exhibits great identity (87.5% at the nucleotide level and 94% at the amino acid level) with the hsp70 gene copies of D. melanogaster, while the second strand ORF, in antiparallel in-frame register arrangement, is 1,839 nucleotides long and exhibits 32% identity with a putative, recently identified, NAD+-dependent glutamate dehydrogenase (NAD+-GDH). The overlap of the two ORFs is 1,824 nucleotides long. Computational analysis shows that this LAC ORF arrangement is conserved in other hsp70 loci in a wide range of organisms, raising questions about possible evolutionary benefits of such a peculiar genomic organization.Correspondence to: Z.G. Scouras 相似文献