Effect of miR-26b on gestational diabetes mellitus in rats via PI3K/Akt signaling pathway.

OBJECTIVE: The aim of this study was to explore the influence of micro ribonucleic acid (miR)-26b on gestational diabetes mellitus in rats via the phosphatidylinositol 3-hydroxy kinase/protein kinase B (PI3K/Akt) signaling pathway. MATERIALS AND METHODS: A total of 60 healthy pregnant female rats were randomly divided into three groups, including group A (normal group), group B (model group), and group C (model + miR-26b group). The differences in fasting blood glucose (FBG), C-reactive protein (CRP), and phosphatidylinositol 3-hydroxy kinase/protein kinase B (PI3K/AKT) among the three groups were analyzed via serum CRP test, morphological observation, quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR), and Western blotting, respectively. RESULTS: The levels of FBG ad CRP were significantly up-regulated in group B when compared with group A (p<0.01). Meanwhile, they increased significantly in group C when compared with group B (p<0.01). Rats in group A exhibited smooth and flat thoracic aortic intimas, as well as neatly arranged smooth muscle cells at the media layer. However, rats in group B showed fractured intimas with enlarged junction gaps, as well as necrotic and detached endothelial cells. Compared with group B, group C exhibited extremely poorly arranged cells at all the layers, rough and rugged intimas, larger areas of necrotic and detached endothelial cells, and markedly worsened lesions. QRT-PCR results indicated that the expression of phosphorylated-PI3K (p-PI3K) was significantly lower in group B than that of group A (p=0.04). Meanwhile, it was markedly lower in group C than that in group B (p=0.04). The expression of p-Akt was remarkably lower in group B than group A (p=0.04), which was also significantly lower in group C than group B (p=0.04). Compared with group A, the expressions of p-PI3K and p-Akt in the thoracic aorta of group B were evidently down-regulated (p<0.01). Furthermore, they decreased markedly in group C when compared with group B (p<0.01). CONCLUSIONS: MiR-26b accelerates the progression of gestational diabetes by inhibiting the PI3K/Akt signaling pathway.

LncRNA CCAT1 promotes the progression of preeclampsia by regulating CDK4.

OBJECTIVE: Preeclampsia is one of the leading causes of maternal and perinatal deaths. This study mainly explored the mechanism of long non-coding RNA (lncRNA) CCAT1 expression in the placenta of preeclampsia patients and its effect on the progression of preeclampsia. MATERIALS AND METHODS: We used quantitative reverse transcription PCR (qRT­PCR) to detect the lncRNA CCAT1 expression in 40 preeclampsia and 40 normal pregnancy placenta samples. CCAT1 expression and its relationship with the clinicopathological parameters of preeclampsia was statistically analyzed. The specific small interfering RNA (si-CCAT1) and plasmid (pcDNA-CCAT1) targeting lncRNA CCAT1 were synthesized and transfected into Bew and JEG-3 cells. The CCAT1 expression in Bew and JEG-3 cells was determined by qRT­PCR. The effect of overexpression and interference of lncRNA CCAT1 on the proliferation of Bew and JEG-3 cells was observed. The effect of CCAT1 on cell cycle was examined by cell cycle assay. The protein expression was accessed by Western blot. RESULTS: Higher lncRNA CCAT1 expression was found in preeclampsia patients. The systolic blood pressure, diastolic blood pressure and urine protein in preeclampsia patients were significantly higher than those in normal pregnant women. The birth weight of fetus was significantly lower than that of normal pregnant women. However, there was no significant difference in weight and age of patients. According to the CCAT1 expression, preeclampsia patients were assigned into high expression group and low expression group. Higher systolic blood pressure, diastolic blood pressure, and urinary protein levels in CCAT1 high expression group were observed comparing to those in low expression group, while the birth weight in low expression group was significantly higher than the high expression group. In addition, we found that after interference with CCAT1, trophoblast proliferation was significantly increased and cell cycle was significantly accelerated, whereas overexpression of CCAT1 led to the contrary. Western blotting indicated that the expressions of E2F1, cyclin D, CDK2 and CDK4 in BeWo cells were increased after CCAT1 was knocked down. The expressions of E2F1, cyclin D, CDK2 and CDK4 in JEG3 cells were decreased after CCAT1 was overexpressed. CONCLUSIONS: LncRNA CCAT1 was highly expressed in preeclampsia and can promote the progression of preeclampsia by inhibiting the expression of CDK4.

MiR-210 protects cardiomyocytes from OGD/R injury by inhibiting E2F3.

OBJECTIVE: To detect the change in miRNA-210 expression of cardiomyocytes under hypoxia/reoxygenation status. Also, the effect of miR-210 on the apoptosis of cardiomyocytes induced by oxygen-glucose deprivation/reperfusion (OGD/R) and its mechanism through establishing the OGD/R injury model of primary cardiomyocytes in this experiment were investigated. MATERIALS AND METHODS: The cell model of OGD/R injury was established. The cell apoptosis in each group was detected by methyl thiazolyl tetrazolium (MTT) assay and detection of Caspase-3 activity. The change in miR-210 expression in each group was detected by Real-time fluorescence quantitative polymerase chain reaction (PCR). The high-expression and low-expression miR-210 models were established through the transient transfection of miR-210 mimic and inhibitor to detect the relevant indexes of cell apoptosis. At the same time, changes in mRNA and protein expressions of E2F3 were detected by RT-PCR and Western blotting, respectively. The E2F3 overexpression vector was constructed, and the overexpression vector plasmid and miR-210 mimic were jointly transfected into the cells to detect the relevant indexes of cell apoptosis. RESULTS: After OGD/R treatment, the activity of Caspase-3 was increased, the survival of cardiomyocytes was significantly inhibited and the expression level of miR-210 was up-regulated in OGD/R injury. Transfection of miR-210 mimic for miR-210 overexpression could alleviate the OGD/R-induced cardiomyocyte injury, while the decrease of miR-210 expression could aggravate the apoptosis of cardiomyocytes. In addition, the high expression of miR-210 could inhibit the protein expression of E2F3, and co-transfection of E2F3 plasmid and miR-210 mimic could reverse the inhibiting effect of miR-210 on the apoptosis of cardiomyocytes. CONCLUSIONS: We confirmed that miR-210 can inhibit the OGD/R-induced apoptosis of cardiomyocytes, and miR-210, as an upstream factor, plays a protective role in cardiomyocytes through directly inhibiting the protein expression of its target gene E2F3.