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201.
Zheng Wang Zhongmin Wang Lu Gao Lili Xiao Rui Yao Binbin Du Yapeng Li Leiming Wu Cui Liang Zhen Huang Pengcheng Li Yanzhou Zhang 《Journal of cellular physiology》2020,235(3):2149-2160
miR-222 participates in many cardiovascular diseases, but its effect on cardiac remodeling induced by diabetes is unclear. This study evaluated the functional role of miR-222 in cardiac fibrosis in diabetic mice. Streptozotocin (STZ) was used to establish a type 1 diabetic mouse model. After 10 weeks of STZ injection, mice were intravenously injected with Ad-miR-222 to induce the overexpression of miR-222. miR-222 overexpression reduced cardiac fibrosis and improved cardiac function in diabetic mice. Mechanistically, miR-222 inhibited the endothelium to mesenchymal transition (EndMT) in diabetic mouse hearts. Mouse heart fibroblasts and endothelial cells were isolated and cultured with high glucose (HG). An miR-222 mimic did not affect HG-induced fibroblast activation and function but did suppress the HG-induced EndMT process. The antagonism of miR-222 by antagomir inhibited HG-induced EndMT. miR-222 regulated the promoter region of β-catenin, thus negatively regulating the Wnt/β-catenin pathway, which was confirmed by β-catenin siRNA. Taken together, our results indicated that miR-222 inhibited cardiac fibrosis in diabetic mice via negatively regulating Wnt/β-catenin-mediated EndMT. 相似文献
202.
203.
Lei Cai Shao-Li Deng Li Liang Hui Pan Jia Zhou Mei-Yan Wang Jun Yue Chun-Ling Wan Guang He Lin He 《Human genetics》2013,132(3):265-273
Genetic factors play important roles in the development of tuberculosis (TB). SP110 is a promising candidate target for controlling TB infections. However, several studies associating SP110 single nucleotide polymorphisms (SNPs) with TB have yielded conflicting results. This may be partly resolved by studying other genes associated with SP110, such as MYBBP1A and RELA. Here, we genotyped 6 SP110 SNPs, 8 MYBBP1A SNPs and 5 RELA SNPs in 702 Chinese pulmonary TB patients and 425 healthy subjects using MassARRAY and SNaPshot methods. Using SNP-based analysis with Bonferroni correction, rs3809849 in MYBBP1A [Pcorrected (cor) = 0.0038] and rs9061 in SP110 (Pcor = 0.019) were found to be significantly associated with TB. Furthermore, meta-analysis of rs9061 in East Asian populations showed that the rs9061 T allele conferred significant risk for TB [P = 0.002, pooled odds ratio (OR), 1.24, 95 % confidence interval (CI) = 1.08–1.43]. The MYBBP1A GTCTTGGG haplotype and haplotypes CGACCG/TGATTG within SP110 were found to be markedly and significantly associated with TB (P = 2.00E?06, 5.00E?6 and 2.59E?4, respectively). Gene-based analysis also demonstrated that SP110 and MYBBP1A were each associated with TB (Pcor = 0.011 and 0.035, respectively). The logistic regression analysis results supported interactions between SP110 and MYBBP1A, indicating that subjects carrying a GC/CC genotype in MYBBP1A and CC genotype in SP110 possessed the high risk of developing TB (P = 1.74E?12). Our study suggests that a combination of SP110 and MYBBP1A gene polymorphisms may serve as a novel marker for identifying the risk of developing TB in the Chinese Han population. 相似文献
204.
205.
Yan Zhang Yan-Wei Li Ya-Xin Wang Hong-Tao Zhang Xiao-Mei Zhang Yu Liang Xiu-Shan Zhang Wen-Sheng Wang Hai-Gen Liu Yi Zhang Ling Zhang Yu-Hua Zheng 《Molecular biology reports》2013,40(12):6997-7006
Tumor necrosis factor (TNF) and the TNF receptor (TNFR) superfamily play very important roles for cell death as well as normal immune regulation. Previous studies have strongly suggested that c-Jun N-terminal kinase (JNK) signaling pathway plays a critical role in ischemic brain injury. The purpose of this investigation was to examine the protective effect of remifentanil preconditioning in cerebral ischemia/reperfusion injury (CIR) and its possible molecular mechanism. Results showed that Remifentanil pretreatment significantly decreased the CD4+ and increased the CD8+ in cerebral tissues. Additionally, CD4+/CD8+ in CIR + Remifentanil group was markedly lower than that in CIR group. TNF-α and TNFR1 in CIR + Remifentanil group rats was found to be significant lower than that in CIR group rats. The expression levels of Cyt-c, caspase-3, caspase-9 and pJNK proteins in brain of CIR + Remifentanil group rats were found to significantly decreased compared to CIR group rats. In addition, decreased ROS level indirectly inhibit JNK activation and cell death in CIR rat receiving Remifentanil preconditioning. From current experiment results, at least two signal pathways involve into the process of Remifentanil preconditioning inhibiting cerebral damage induced by ischemia reperfusion. The inhibitory effects of Remifentanil preconditioning on the brain damage are achieved probably through blocking the activation of TNF-α/TNFR1, JNK signal transduction pathways, which implies that Remifentanil preconditioning may be a potential and effective way for prevention of the ischemic/reperfusion injury through the suppression extrinsic apoptotic signal pathway induced by TNF-α/TNFR1, JNK signal pathways. Taken together, this study indicated that regulation of the TNF-α/TNFR1 and JNK signal pathways may provide a new therapy for cerebral damage induced by ischemia and reperfusion. 相似文献
206.
207.
Wang Xinhong Liu Weimin Wu Yue Liu Xiaojun Liang Xiao Wan Zhaofei Wang Nanping Yuan Zuyi 《Molecular and cellular biochemistry》2013,377(1-2):131-141
Glycodelin A (GdA) is a dimeric glycoprotein synthesized by the human endometrium under progesterone regulation. Based on the high sequence similarity with β-lactoglobulin, it is placed under the lipocalin superfamily. The protein is one of the local immunomodulators present at the feto-maternal interface which affects both the innate as well as the acquired arms of the immune system, thereby bringing about successful establishment and progression of pregnancy. Our previous studies revealed that the domain responsible for the immunosuppressive activity of glycodelin lies on its protein backbone and the glycans modulate the same. This study attempts to further delineate the apoptosis inducing region of GdA. Our results demonstrate that the stretch of amino acid sequence between Met24 to Leu105 is necessary and sufficient to inhibit proliferation of T cells and induce apoptosis in them. Further, within this region the key residues involved in harboring the activity were shown to be present between Asp52 and Ser65. 相似文献
208.
Yinghui Li Yuxiao Huang Jiao Liang Zhikai Xu Yan Shen Ning Zhang Zhongxiang Liu Ya Zhao 《Molecular biology reports》2013,40(4):2781-2787
CD8+ T cells play an important role in early HIV infection. However, HIV has the capacity to avoid specific CTL responses due to a high rate of mutation under selection pressure. Although the HIV proteins, gag and pol, are relatively conserved, these sequences generate low-affinity MHC-associated epitopes that are poorly immunogenic. Here, we applied an approach that enhanced the immunogenicity of low-affinity HLA-A2.1-binding peptides. The first position with tyrosine (P1Y) substitution enhanced the affinity of HLA-A2.1-associated peptides without altering their antigenic specificity. More importantly, P1Y variants efficiently stimulated in vivo native peptide-specific CTL that also recognized the corresponding naturally processed epitope. The potential to generate CTL against any low-affinity HLA-A2.1-associated peptide provides us with the necessary technique for identification of virus cryptic epitopes for development of peptide-based immunotherapy. Therefore, identification and modification of the cryptic epitopes of gal and pol provides promising candidates for HIV immunotherapy dependent upon efficient presentation by virus cells. Furthermore, this may be a breakthrough that overcomes the obstacle of immune escape caused by high rates of mutation. In this study, bioinformatics analysis was used to predict six low-affinity cryptic HIV gag and pol epitopes presented by HLA-A*0201. A HIV compound multi-CTL epitope gene was constructed comprising the gene encoding the modified cryptic epitope and the HIV p24 antigen, which induced a strong CD8+ T cell immune response regardless of the mutation. This approach represents a novel strategy for the development of safe and effective HIV prophylactic and therapeutic vaccines. 相似文献
209.
Jin Huang Jichong Huang Yaxian Ma Haichuan Wang Jiqiao Yang Tianyuan Xiong Liang Du 《Molecular biology reports》2013,40(7):4219-4225
The Cdx-2 polymorphism in VDR gene has been extensively investigated for association with cancer risk, however, results of different studies have been inconsistent. The objective of this study is to assess the relationship of the Cdx-2 polymorphism in VDR and cancer risk by meta-analysis. All eligible case–control studies were searched in Pubmed, Embase, CNKI and Wanfang databases. Odds ratios (OR) with the 95 % confidence intervals (CI) were used to assess the association. A total of 12,906 cases and 13,700 controls in 18 case–control studies were included. The results indicated that the AA homozygote carriers had a 16 % increased risk of cancer, when compared with the homozygote GG and heterozygote AG (OR = 1.16, 95 % CI 1.05–1.29 for AA vs. GG+AG). In the subgroup analysis by ethnicity, significant elevated risks were associated with AA homozygote carriers in Caucasians (OR = 1.16, 95 % CI 1.01–1.33, and P = 0.04) and African Americans (OR = 1.31, 95 % CI 1.07–1.61, and P = 0.01). In the subgroup analysis by cancer types, the polymorphism was associated with increased risk of breast cancer (OR = 1.23, 95 % CI 1.04–1.46, and P = 0.02). This meta-analysis suggested that the Cdx-2 polymorphism of VDR gene would be a risk factor for cancer. To further evaluate gene-to-gene and gene-to-environmental interactions between polymorphisms of VDR gene and cancer risk, more studies with large groups of patients are required. 相似文献
210.
The genus Mentha comprises a group of aromatic plants with worldwide distribution. Because of frequent interspecific hybridization, the genetic relationships within the genus are not clearly understood. Limonene synthase, which catalyses the first committed step in the essential oil monoterpene biosynthetic pathway, is considered to be a possible rate limiting enzyme. With the homology-based cloning method, primers were designed according to cDNA sequence to amplify full-length DNA sequences in 13 Mentha samples from five species, using Perilla as an outgroup. Analyses of gene structure, length variation, GC-content, Ts/Tv ratio and evolutionary diversity were carried out. Consensus phylogenetic trees were obtained using maximum likelihood, neighbor-joining, and maximum parsimony, respectively, based on the full-length genomic DNA sequences, complete ORF coding sequences and predicted amino acid sequences. The results presented here based on the sequence of MhLS provide the first credibly supported genetic relationships for Mentha, which enables a basis for further mint taxonomy, cultivation and breeding. 相似文献