MicroRNA-137 Inhibited Hypoxia-Induced Proliferation of Pulmonary Artery Smooth Muscle Cells by Targeting Calpain-2.

The proliferation of pulmonary artery smooth muscle cells (PASMCs) is an important cause of pulmonary vascular remodeling in pulmonary hypertension (PH). It has been reported that miR-137 inhibits the proliferation of tumor cells. However, whether miR-137 is involved in PH remains unclear. In this study, male Sprague-Dawley rats were subjected to 10% O2 for 3 weeks to establish PH, and rat primary PASMCs were treated with hypoxia (3% O2) for 48 h to induce cell proliferation. The effect of miR-137 on PASMC proliferation and calpain-2 expression was assessed by transfecting miR-137 mimic and inhibitor. The effect of calpain-2 on PASMC proliferation was assessed by transfecting calpain-2 siRNA. The present study found for the first time that miR-137 was downregulated in pulmonary arteries of hypoxic PH rats and in hypoxia-treated PASMCs. miR-137 mimic inhibited hypoxia-induced PASMC proliferation and upregulation of calpain-2 expression in PASMCs. Furthermore, miR-137 inhibitor induced the proliferation of PASMCs under normoxia, and knockdown of calpain-2 mRNA by siRNA significantly inhibited hypoxia-induced proliferation of PASMCs. Our study demonstrated that hypoxia-induced downregulation of miR-137 expression promoted the proliferation of PASMCs by targeting calpain-2, thereby potentially resulting in pulmonary vascular remodeling in hypoxic PH.

MEIS1 regulated proliferation and migration of pulmonary artery smooth muscle cells in hypoxia-induced pulmonary hypertension.

AIM: Proliferation and migration of pulmonary artery smooth muscle cells (PASMCs) are regarded as the primary factors resulting in pulmonary arterial remodeling in pulmonary hypertension (PH). Myeloid ecotropic viral integration site 1 (MEIS1) has been positioned as a negative cardiomyocyte cell cycle regulator and regulates proliferation of multiple kinds of cancer cells. Whether MESI1 is involved in the proliferation and migration of PASMCs deserves to be identified. MAIN METHODS: Sprague Dawley rats were exposed to hypoxia condition (10% O2) for 4 weeks to induce PH and primary rat PASMCs were cultured in hypoxia condition (3% O2) for 48 h to induce proliferation and migration. Immunohistochemistry, immunofluorescence, reverse transcription PCR and Western blot analysis were performed to detect the expressions of target mRNAs and proteins. EDU, CCK8 and wound healing assays were conducted to measure the proliferation and migration of PASMCs. KEY FINDINGS: Hypoxia down-regulated the expression of MEIS1 (both mRNA and protein) in pulmonary arteries and PASMCs. Over-expression of MEIS1 inhibited the proliferation and migration of PASMCs afforded by hypoxia. In contrast, knockdown of MEIS1 under normoxia condition like hypoxia induced the proliferation and migration of PASMCs. MEIS1 mediated hypoxia-induced the proliferation and migration of PASMCs via METTL14/MEIS1/p21 signaling. SIGNIFICANCE: The present study revealed that MEIS1 regulated the proliferation and migration of PASMCs during hypoxia-induced PH. Thus, MEIS1 may be a potential target for PH therapy.

Up-regulation of cullin7 promotes proliferation and migration of pulmonary artery smooth muscle cells in hypoxia-induced pulmonary hypertension.

It has well been demonstrated that E3 ubiquitin ligase cullin7 plays important roles in cancer cell growth control via down-regulating p53 expression. The noncanonical function or the pathogenic role of p53 has more recently been implicated in pulmonary vascular remodeling. Therefore, whether cullin7 participates in hypoxia-induced pulmonary vascular remodeling deserves to be elucidated. The present study found that hypoxia up-regulated the expression of cullin7 mRNA and protein in pulmonary arteries and pulmonary artery smooth muscle cells, and knockdown of cullin7 inhibited hypoxia-induced proliferation and migration of pulmonary artery smooth muscle cells and reversed hypoxia-induced inhibition of p53 expression. Notably, administration of proteasome inhibitor MG132 significantly inhibited the expression of cullin7 and up-regulated the expression of p53 in pulmonary arteries concomitantly with improvement of hypoxia-induced pulmonary vascular remodeling. Our study demonstrated that hypoxia induced up-regulation of cullin7 expression resulting to the proliferation and migration of pulmonary artery smooth muscle cells via down-regulating p53 expression, which contributed to pulmonary vascular remodeling.

Expression of soluble vascular endothelial growth factor receptor-1 and placental growth factor in fetal growth restriction cases and intervention effect of tetramethylpyrazine.

OBJECTIVE: To investigate the expression of soluble vascular endothelial growth factor receptor-1 (sFlt-1) and placental growth factor (PLGF) in the fetal growth restriction (FGR) cases and the intervention mechanism of tetramethylpyrazine. METHODS: A total of 60 fetal growth restriction cases that admitted to our hospital were randomly divided into ligustrazine intervention group (group A) and nutritional support group (group B). A total of 50 healthy pregnant women were also enrolled as control group (group C). Expression level of maternal serum sFlt1, PLGF and fetal growth parameters including HC, AC, FL, BPD, EFW as well as placenta PLGF, sFlt-1 mRNA expression were recorded and compared among the three groups. A total of 15 SD rats were selected and were divided into three groups, TMP group, alcohol and tobacco group and blank control group. Three groups of rats were dissected on the twentieth day of gestation. RESULTS: Expression level of sFlt-1 and PLGF in group A was not significantly different from that of group C (P>0.05); but significant difference in SFlt1 and PLGF expression level was observed between group C and group B (P<0.05). Before treatment, HC, AC, FL, BPD and EFW of group A and group B were significant lower than those of group C, but after treatment, those parameters in group A were significantly improved (P<0.05). In the animal experiment there was no significant difference in sFlt-1 between treatment group and FGR group without treatment or control group (P>0.05). There was significant difference in PLGF between FGR group with treatment and FGR group without treatment or control group (P<0.01). CONCLUSIONS: PLGF level is decreased and sFlt-1 increased in patients suffered from fetal growth restriction, and FGR rats show increased sFlt-1 and decreased PLGF, thus they can be indicator of the fetal growth restriction. Ligustrazine can effectively improve sFlt-1, PLGF expression level in fetal growth restriction cases, which can be used as treatment for FGR.

Safety assessment of ovarian cryopreservation and transplantation in nude mice bearing human epithelial ovarian cancer.

OBJECTIVE: Nude mice with orthotopic transplantation of human ovarian epithelial cancer were used to investigate screening criteria for paraneoplastic normal ovarian tissue and the security of the freezing and thawing for ovarian tissue transplantation. METHODS: Expression of CK-7, CA125, P53, survivin, MMP-2/TIMP- 2 in paraneoplastic normal ovarian tissues were detected by RT-PCR as well as immunohistochemistry. The tissues of the groups with all negative indicators of RT-PCR, all negative indicators of immunohistochemistry, negative expression of CK-7, CA125 and survivin, positive expression of CK-7, CA125 and survivin, cancer tissues and normal ovarian tissues of nude mice were used for freezing and thawing transplantation, to analyze overt and occult carcinogenesis rates after transplantation. RESULTS: When all indicators or the main indicators, CK-7, CA125 and survivin, were negative, tumorigenesis did not occur after transplantation. In addition the occult carcinogenesis rate was lower than in the group with positive expression of CK-7, CA125 and survivin (P<0.01). After subcutaneous and orthotopic transplantation of ovarian tissues, rates did not change (P>0.05). There was no statistical significance among rates after transplantation of ovarian tissues which were obtained under different severity conditions (P>0.05). CONCLUSION: Negative expression of CK-7, CA125 and survivin can be treated as screening criteria for security of ovarian tissues for transplantation. Immunohistochemical methods can be used as the primary detection approach. Both subcutaneous and orthotopic transplantation are safe. The initial severity does not affect the carcinogenesis rate after tissue transplantation. Freezing and thawing ovarian tissue transplantation in nude mice with human epithelial ovarian carcinoma is feasible and safe.