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101.
Apoptosis of granulosa cells affects follicular atresia and reproduction and is regulated by miRNAs and the expression of certain genes. For the present study, we investigated the regulatory relationship between microRNA‐222 (miR‐222) and THBS1 in porcine follicular granulosa cells (pGCs) and its effects on apoptosis to provide empirical data for developing methods to improve pig fecundity. Results revealed that miR‐222 promotes the proliferation of pGCs. MiRNA mimics and luciferase reporter assays revealed that miR‐222 functions as an anti‐apoptotic factor in pGCs. MiR‐222 mimics in pGCs result in the upregulation of the anti‐apoptotic BCL‐2 gene, down‐regulation of the proapoptotic caspase‐3 gene, and inhibition of apoptosis. MiR‐222 inhibitors reduced BCL‐2 and had no significant effect on caspase‐3. MiR‐222 mimics promoted estrogen levels. Inhibition of THBS1 inhibited pGC apoptosis. Transfection of THBS1‐siRNA reduced the proapoptotic BAX gene. MiR‐222 can directly target the 3′‐untranslated region of the THBS1 gene. MiR‐222 mimics suppressed THBS1 mRNA and proteins, but these were upregulated by the miR‐222 inhibitor. Transfection of THBS1‐siRNA resulted in the inhibition of the miR‐222 inhibitor, which suggests that miR‐222 inhibits pGC apoptosis by targeting THBS1. These findings suggest that miR‐222 and THBS1 play important roles in follicular atresia, ovarian development, and female reproduction.  相似文献   
102.
AIM: To observe the expression of microRNA-126-5p during myocardial injury and its role in myocardial cell injury induced by adriamycin (also called doxorubicin, DOX). METHODS: The BALB/c mouse model of DOX-induced acute and chronic myocardial injury was established via intraperitoneal injection of DOX. HE staining was applied to observe the morphological changes of myocardial tissues. Lactate dehydrogenase (LDH) in serum was detected and PowerLab system was used to detect the influence of DOX on the changes of ±dp/dtmax. The expression of microRNA-126-5p in injured myocardial tissues and the H9c2 cells exposed to DOX was detected by real-time PCR. Gain-and loss-of-function experiments were conducted to detect the role of microRNA-126-5p in H9c2 cells treated with DOX on LDH release and caspase-3 activation. RESULTS: In acute and chronic DOX myocardial damage models in mice, HE staining showed disarranged myocardial fibers, dissolved myofibril and inflammatory cell infiltration. Higher serum LDH level and lower ±dp/dtmax in DOX-treated mice than those in normal mice were found. Compared with the normal mice, the expression level of microRNA-126-5p was significant increased in the myocardium with DOX-induced injury. Similarly, the expression level of microRNA-126-5p was significant increased in the H9c2 cells treated with DOX. In addition, over-expression of microRNA-126-5p decreased cell viability and promoted apoptosis, while microRNA-126-5p ablation promoted the viability and inhibited the apoptosis of H9c2 cells. CONCLUSION: The microRNA-126-5p expression is up-regulated in myocardial injury induced by DOX, and microRNA-126-5p inhibits cell viability and promotes apoptosis induced by DOX.  相似文献   
103.
AIM:To investigate the biological functions of microRNA-29a (miR-29a) in prostate cancer and the molecular mechanism of miR-29a over-expression inhibiting malignant phenotypes of prostate cancer cells. METHODS:The levels of miR-29a expression in the prostate cancer tissues and cells were detected and analyzed using gene microarray and bioinformatics. The expression levels of miR-29a and lysine (K)-specific demethylase 4B (KDM4B) mRNA in prostate cancer tissues, paracarcinomatous tissues, 4 prostate cancer cell lines (PC3, DU145, LNCaP and ArCaP) and normal prostate epithelial cell line (RWPE-1) were measured by real-time PCR. PC3, DU145, LNCaP and ArCaP cells were transfected with pGenesil-1-miR-29a plasmid using transient transfection. The cell viability, colony formation rate and apoptotic rate were analyzed by MTT assay, colony formation assay and flow cytometry with Annexin V-FITC/PI staining, respectively. The protein expression of KDM4B was determined by Western blot. RESULTS:The results of gene microarray and bioinformatic analysis indicated that differential expression of miR-29a was found in the prostate cancer tissues and the paracarcinomatous tissues. The levels of miR-29a in the prostate cancer tissues and prostate cancer cells were significantly decreased, while the mRNA levels of KDM4B were notably increased compared with the paracarcinomatous tissues and RWPE-1 cells, respectively (P<0.05). Compared with negative control (pGenesil-1) group, the cell viability and colony formation rate were significantly decreased, the apoptotic rate was significantly increased, and the protein expression of KDM4B was notably inhibited in the prostate cancer cells with miR-29a over-expression (P<0.05). The cell viability was significantly enhanced, and the apoptosis was significantly inhibited in the prostate cancer cells with KDM4B over-expression (P<0.05). CONCLUSION:Low expression of miR-29a was found in the prostate cancer tissues and cells. miR-29a over-expression inhibits the growth of prostate cancer cells and induces apoptosis. The mechanism may be associated with inhibiting the protein expression of KDM4B.  相似文献   
104.
AIM:To investigate the effects of microRNA-141 (miRNA-141) regulating Nrf2/ARE signaling pathways by targeting Keap1 on the viability of T47D breast cancer cells. METHODS:The breast cancer T47D cells were transfected with miRNA-141 mimic and the negative control sequence (negative control, NC), as miRNA-141 group and NC group, respectively, and the cell without transfection was used as control group. Real-time PCR was used to detect the expression level of miRNA-141. The cell viability was measured by MTT assay. Fluorescent probe 2',7'-dihydrodichlorofluorescein diacetate ester (DCFH-DA) was used to detect cell reactive oxygen species (ROS) level. The protein expression levels of Keap1, nuclear factor E2-related factor 2 (Nrf2), superoxide dismutase 2 (SOD2) and glutathione peroxidase 1 (GPx1) were determined by Western blot. Dual luciferase assay was used to analyze relationship between miRNA-141 and Keap1. RESULTS:After the cells were transfected with miRNA-141 mimic, the expression of miRNA-141 was obviously higher in miRNA-141 group than that in other groups (P<0.05). The cell viability, ROS level and Keap1 protein expression were significantly decreased, while the Nrf2 protein in the nucleus and antioxidants SOD2 and GPx1 expression were up-regulated in miRNA-141 group. Moreover, the luciferase reporter assay demonstrated that Keap1 was the target gene of miRNA-141. CONCLUSION:miRNA-141 may negatively regulates Keap1 and activates Nrf2/ARE signaling pathways, which inhibits the viability of breast cancer cells via inducing the expression of antioxidant enzymes to reduce the oxidative stress levels of the cells.  相似文献   
105.
AIM: To investigate the effect of microRNA (miR)-451 by targeting proteasome subunit β type 8 (Psmb8) on the inflammatory responses in mouse glomerular mesangial cells (MCs) under high-and low-glucose conditions. METHODS: The expression levels of miR-451, IL-18 mRNA and TNF-α mRNA were detected by qPCR. The protein expression levels of IL-18, TNF-α and Psmb8 were determined by Western blot when miR-451 was over-expressed and down-expressed in the MCs. Moreover, the expression of IL-18 and TNF-α was detected when Psmb8 was silenced by si-Psmb8 in MCs. RESULTS: The expression of miR-451 was significantly decreased in the MCs treated with high glucose compared with low glucose group (P<0.01). However, the expression of Psmb8 was increased in high glucose group as compared with low glucose group (P<0.01). Moreover, the expression levels of Psmb8, IL-18 and TNF-α were significantly decreased when miR-451 was over-expressed in high glucose group (P<0.01). Additionally, the expression levels of IL-18 and TNF-α were significantly reduced when Psmb8 was silenced in the MCs under high glucose condition. CONCLUSION: miR-451 reduces the expression of inflammatory factors via targeting Psmb8 in the MCs under high glucose condition. Therefore, miR-451 may play a role in inflammation of diabetic nephropathy.  相似文献   
106.
AIM: To investigate the expression of long non-coding RNA PVT1 in ovarian cancer and the role of PVT1 in migration and invasion abilities of ovarian cancer cells.METHODS: The expression of PVT1 in ovarian cancer tissue, normal ovarian tissue and different ovarian cancer cell lines was detected by qPCR. Transwell assay was used to detect the invasion ability of ovarian cancer cells after PVT1 silencing. The migration ability of the ovarian cancer cells after PVT1 silencing was detected by scratch test. The interaction between PVT1 and microRNA (miR)-551 was analyzed by dual-luciferase reporter assay. The effect of miR-551-inhibitor on the invasion and migration abilities of ovarian cancer cells after PVT1 silencing was detected by Transwell assay and scratch test. The expression of Wnt signaling pathway-related proteins was determined by Western blot after PVT1 silencing. The effects of PVT1 silencing on tumor weight and volume of ovarian cancer were examined by subcutaneous tumor transplantation in nude mice.RESULTS: The expression of PVT1 in ovarian cancer tissue was significantly higher than that in normal ovarian tissue (P<0.05). The expression level of PVT1 in ovarian cancer cell line ES-2 was the highest. PVT1 silencing inhibited the invasion and migration abilities of the ovarian cancer cells. After PVT1 silencing, miR-551-inhibitor promoted the invasion and migration abilities of the ovarian cancer cells. The expression of Wnt signaling pathway-related proteins was decreased after PVT1 silencing (P<0.05). Compared with negative control group, the tumor volume and weight in PVT1-siRNA group were significantly decreased (P<0.05).CONCLUSION: PVT1 plays an important role in the development of ovarian cancer. PVT1 regulates the invasion and migration abilities of ovarian cancer cells through Wnt signaling pathway.  相似文献   
107.
The present study was performed to determine the effectiveness of the Hargreaves test for the evaluation of nociception in frogs, more precisely to determine if cutaneous thresholds to a radiant heat stimulus would increase with analgesics following an abdominal laparotomy performed under general anaesthesia. Non breeding female Xenopus leavis frogs (3 groups (non-anaesthetized, anaesthetized with tricaine methanesulfonate (MS222), with or without an abdominal laparotomy) were used to evaluate the effectiveness of the Hargreaves test. Cutaneous thresholds were evaluated at baseline and following anaesthetic recovery (over 8 h) at six different body locations. Increased reaction times were observed in the gular area only at 1 h post-recovery following a MS222 bath immersion in frogs with (p < 0.02) and without the abdominal laparotomy (p < 0.002). In conclusion, the Hargreaves test does not provide an adequate test to evaluate nociception induced by an abdominal laparotomy and consequently cannot be used to evaluate analgesics in X. leavis frogs.  相似文献   
108.
109.
LIANG Lei  YANG Bo  WU Yuan-yuan  SUN Li 《园艺学报》2021,36(12):2174-2181
AIM To investigate whether microRNA-556-3p (miR-556-3p) regulates the viability, migration and invasion of endometrial cancer cells by targeting SASH1 gene. METHODS The expression of miR-556-3p, and the mRNA and protein levels of SASH1 in endometrial cancer tissues were detected by RT-qPCR and Western blot. Anti-miR-556-3p or pcDNA-SASH1 was transfected into endometrial cancer Ishikawa cells. The cell viability was detected by MTT assay, the migration and invasion abilities of the cells were detected by Transwell chamber method, and the protein expression levels of cyclin D1, p21, matrix metalloproteinase-2 (MMP-2) and MMP-9 were detected by Western blot. StarBase prediction and dual-luciferase reporter experiments were used to analyze the targeting relationship between miR-556-3p and SASH1. Anti-miR-556-3p and si-SASH1 were co-transfected into the Ishikawa cells, and their effects on cell viability, migration and invasion were examined by the methods described above. RESULTS Compared with adjacent tissues, the expression of miR-556-3p in endometrial cancer tissues was increased significantly, and the expression of SASH1 at mRNA and protein levels was decreased significantly (P<0.05). Inhibition of miR-556-3p expression or induction of SASH1 over-expression obviously reduced the viability of Ishikawa cells, the number of migratory cells, the number of invasive cells and the protein levels of cyclin D1, MMP-2 and MMP-9, and dramatically increased the protein level of p21 (P<0.05). miR-556-3p targeted SASH1 and negatively regulated its expression. Knock-down of SASH1 expression reversed the inhibitory effect of miR-556-3p expression inhibition on the viability, migration and invasion of Ishikawa cells. CONCLUSION Inhibition of miR-556-3p expression suppresses the viability, migration and invasion of endometrial cancer cells. The mechanism is related to the regulation of its target gene SASH1.  相似文献   
110.
We used blood vessel myography and a perfused tail preparation from the Chinook salmon (Oncorhynchus tshawytscha) to investigate the effect of 2 commercially used fish anaesthetics, AQUI-STM and MS222, on vascular tone. Hepatic portal vein rings were exposed to 1 × 10−7 M adrenaline in the presence or absence of either AQUI-STM or MS222 and changes in vessel tension measured. Tail preparations were perfused with saline containing increasing concentrations of either anaesthetic. Exposure to either anaesthetic did not alter the response of vessel rings to adrenaline in vitro. However, both anaesthetics caused a significant (P ≤ 0.05) decrease in vessel tension when compared to controls. In tail preparations, perfusion with either anaesthetic caused a significant (P ≤ 0.05) yet reversible, dose dependent decrease in vascular resistance. Further to this, it was found that for both anaesthetics there was a significant effect of fish holding time on the response of preparations, with fish that were acclimated for less than 1 week exhibiting less vasodilation in response to anaesthetic exposure. We conclude that commonly used concentrations of AQUI-STM and MS222 can have a direct effect on vascular tone of salmon vessels, causing a significant but reversible vasodilation of vessels. This vasodilation may offset increases in haematocrit seen during anaesthesia in the whole animal, and in recovery prevent large rises in peripheral resistance associated with catecholamine release. A reduced vascular resistance may allow the heart to pump greater volumes of blood during recovery.  相似文献   
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