Effective treatment and/or prevention strategies for neonatal persistent pulmonary hypertension of the newborn (PPHN) have been an important topic in neonatal medicine. However, mechanisms of impaired pulmonary vascular structure in hypoxia-induced PPHN are poorly understood and consequently limit the development of effective treatment. In this study, we aimed to explore the molecular signaling cascades in the lungs of a PPHN animal model and used primary cultured rat pulmonary microvascular endothelial cells to analyze the physiological benefits of ghrelin during the pathogenesis of PPHN. Randomly selected newborn rats were exposed to hypoxia (10–12%) or room air and received daily s.c. injections of ghrelin (150 μg/kg) or saline. After 2 weeks, pulmonary hemodynamics and morphometry were assessed in the rats. Compared with the control, hypoxia increased pulmonary arterial pressure, right ventricle (RV) hypertrophy, and arteriolar wall thickness. Ghrelin treatment reduced both the magnitude of PH and the RV/(left ventricle+septum (Sep)) weight ratio. Ghrelin protected neonatal rats from hypoxia-induced PH via the upregulation of phosphorylation of glycogen synthase kinase 3β (p-GSK3β)/β-catenin signaling and associated with β-catenin translocation to the nucleus in the presence of growth hormone secretagogue receptor-1a. Our findings suggest that s.c. administration of ghrelin improved PH and attenuated pulmonary vascular remodeling after PPHN. These beneficial effects may be mediated by the regulation of p-GSK3β/β-catenin expression. We propose ghrelin as a novel potential therapeutic agent for PPHN.
Yan-ping Xu, Jia-jun Zhu, Fen Cheng, Ke-wen Jiang, Wei-zhong Gu, Zheng Shen, Yi-dong Wu, Li Liang and Li-zhong Du
Juan Liu, Xiaocen Kong, Long Wang, Hanmei Qi, Wenjuan Di, Xiao Zhang, Lin Wu, Xia Chen, Jing Yu, Juanmin Zha, Shan Lv, Aisen Zhang, Peng Cheng, Miao Hu, Yujie Li, Jianhua Bi, Yan Li, Fang Hu, Yi Zhong, Yong Xu and Guoxian Ding
Brown adipose tissue (BAT) increases energy expenditure and is an attractive therapeutic target for obesity. 11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1), an amplifier of local glucocorticoid activity, has been shown to modulate white adipose tissue (WAT) metabolism and function. In this study, we investigated the roles of 11β-HSD1 in regulating BAT function. We observed a significant increase in the expression of BAT-specific genes, including UCP1, Cidea, Cox7a1, and Cox8b, in BVT.2733 (a selective inhibitor of 11β-HSD1)-treated and 11β-HSD1-deficient primary brown adipocytes of mice. By contrast, a remarkable decrease in BAT-specific gene expression was detected in brown adipocytes when 11β-HSD1 was overexpressed, which effect was reversed by BVT.2733 treatment. Consistent with the in vitro results, expression of a range of genes related to brown fat function in high-fat diet-fed mice treated with BVT.2733. Our results indicate that 11β-HSD1 acts as a vital regulator that controls the expression of genes related to brown fat function and as such may become a potential target in preventing obesity.
Rubab Akbar, Kamran Ullah, Tanzil Ur Rahman, Yi Cheng, Hai-Yan Pang, Lu-Yang Jin, Qi-Jing Wang, He-Feng Huang and Jian-Zhong Sheng
Receptive endometrium is a prerequisite for successful embryo implantation, and it follows that poor endometrial receptivity is a leading cause of implantation failure. miRNAs play important roles as epigenetic regulators of endometrial receptivity and embryo implantation through post-transcriptional modifications. However, the mechanisms of action of many miRNAs are poorly understood. In this study, we investigated the role of the miR-183 family, comprising three miRNAs (miR-183-5p, miR-182-5p, and miR-96-5p) in endometrial receptivity and embryo implantation. The miR-183 family shows estrogen-dependent upregulation in endometrial Ishikawa (IK) cells. The miR-183 family also has a positive role in migration and proliferation of IK cells. Furthermore, JAr spheroid attachment experiments show that attachment rates were significantly decreased after treatment of IK cells with inhibitors for miR-183-5p and miR-182-5p and increased after treatment with miR-183-5p-mimic and miR-96-5p-mimic, respectively. The downstream analysis shows that catenin alpha 2 (CTNNA2) is a potential target gene for miR-183-5p, and this was confirmed in luciferase reporter assays. An in vivo mouse pregnancy model shows that inhibition of miR-183-5p significantly decreases embryo implantation rates and increases CTNNA2 expression. Downregulation of CTNNA2 in endometrial cells by miR-183-5p may be significant in mediating estrogenic effects on endometrial receptivity. In conclusion, miR-183-5p and the CTNNA2 gene may be potential biomarkers for endometrial receptivity and may be useful diagnostic and therapeutic targets for successful embryo implantation.
Kamran Ullah, Tanzil Ur Rahman, Hai-Tao Pan, Meng-Xi Guo, Xin-Yan Dong, Juan Liu, Lu-Yang Jin, Yi Cheng, Zhang-Hong Ke, Jun Ren, Xian-Hua Lin, Xiao-Xiao Qiu, Ting-Ting Wang, He-Feng Huang and Jian-Zhong Sheng
Previous studies have shown that increasing estradiol concentrations had a toxic effect on the embryo and were deleterious to embryo adhesion. In this study, we evaluated the physiological impact of estradiol concentrations on endometrial cells to reveal that serum estradiol levels probably targeted the endometrium in controlled ovarian hyperstimulation (COH) protocols. An attachment model of human choriocarcinoma (JAr) cell spheroids to receptive-phase endometrial epithelial cells and Ishikawa cells treated with different estradiol (10−9 M or 10−7 M) concentrations was developed. Differentially expressed protein profiling of the Ishikawa cells was performed by proteomic analysis. Estradiol at 10−7 M demonstrated a high attachment rate of JAr spheroids to the endometrial cell monolayers. Using iTRAQ coupled with LC–MS/MS, we identified 45 differentially expressed proteins containing 43 significantly upregulated and 2 downregulated proteins in Ishikawa cells treated with 10−7 M estradiol. Differential expression of C3, plasminogen and kininogen-1 by Western blot confirmed the proteomic results. C3, plasminogen and kininogen-1 localization in human receptive endometrial luminal epithelium highlighted the key proteins as possible targets for endometrial receptivity and interception. Ingenuity pathway analysis of differentially expressed proteins exhibited a variety of signaling pathways, including LXR/RXR activation pathway and acute-phase response signaling and upstream regulators (TNF, IL6, Hmgn3 and miR-140-3p) associated with endometrial receptivity. The observed estrogenic effect on differential proteome dynamics in Ishikawa cells indicates that the human endometrium is the probable target for serum estradiol levels in COH cycles. The findings are also important for future functional studies with the identified proteins that may influence embryo implantation.