Search Results

You are looking at 1 - 3 of 3 items for

  • Author: Na Li x
Clear All Modify Search
Free access

Yang Mi, Na Guo, Tongqiang He, Jing Ji, Zhibin Li and Pu Huang

Gestational diabetes mellitus (GDM) is a condition commonly encountered during mid to late pregnancy with pathologic manifestations including hyperglycemia, hyperinsulinemia, insulin resistance, and fetal mal-development. The deficit and dysfunction of insulin secreting β-cells are signature symptoms for GDM. Pancreatic progenitors derived from human embryonic stem cells (hESCs) were shown to be able to effectively treat diabetes in mice. In this study, we first identified that microRNA-410 (miR-410) directly targets lactate dehydrogenase A (LDHA), a gene selectively repressed in normal insulin secreting β-cells. hESCs that can be induced to express miR-410 hence keeping LDHA levels in check were then differentiated in vitro into pancreatic endoderm, followed by transplantation into db/ + mouse model of GDM. The transplant greatly improved glucose metabolism and reproductive outcome of the pregnant females suffering from GDM. Our findings describe for the first time the method of combining miRNA with hESCs, providing proof of concept by employing genetically modified stem cell therapy for treating GDM.

Free access

Zhiyu Ma, Ying Zhang, Juan Su, Sheng Yang, Wenna Qiao, Xiang Li, Zhihai Lei, Ling Cheng, Na An, Wenshao Wang, Yanyan Feng and Jinlong Zhang

Neuromedin B (NMB), a mammalian bombesin-related peptide, has numerous physiological functions, including regulating hormone secretions, cell growth, and reproduction, by binding to its receptor (NMBR). In this study, we investigated the effects of NMB on testosterone secretion, steroidogenesis, cell proliferation, and apoptosis in cultured primary porcine Leydig cells. NMBR was mainly expressed in the Leydig cells of porcine testes, and a specific dose of NMB significantly promoted the secretion of testosterone in the primary Leydig cells; moreover, NMB increased the expression of mRNA and/or proteins of NMBR and steroidogenic mediators (steroidogenic acute regulatory (STAR), CYP11A1, and HSD3B1) in the Leydig cells. In addition, specific doses of NMB promoted the proliferation of Leydig cells and increased the expression of proliferating cell nuclear antigen and Cyclin B1 proteins, while suppressing Leydig cell apoptosis and decreasing BAX and Caspase-3 protein expression. These results suggest that the NMB/NMBR system might play an important role in regulating boar reproductive function by modulating steroidogenesis and/or cell growth in porcine Leydig cells.

Restricted access

Yun-Qing Zhu, Yun Hu, Ke He, Na Li, Peng Jiang, Yu-Qin Pan, Hong Zhou and Xiao-Ming Mao

The follicles are the minimal functional unit of the thyroid; the morphology and the function of each follicle can vary significantly. However, the reasons for the apparent follicular heterogeneity are poorly understood. Some tissue-resident regulatory T cells (Tregs) have a special phenotype that expresses unique molecules related to local tissue and regulates the tissue functions. The aim of this study was to identify the phenotype of thyroid Tregs and the roles of thyroid Tregs in thyroid physiological regulation. Thyroid tissue and peripheral blood samples were obtained from patients with benign thyroid nodules. Microarray-based gene expression, flow cytometry, immunofluorescence microscopy, and functional analysis of thyroid Tregs were performed. Here, we demonstrated that human thyroid Tregs expressed high level of thyroglobulin (Tg), both gene and protein. The immunofluorescence microscopy of thyroid section showed that the FOXP3+Tg+ cells concentrated in some of the thyroid follicles, at the side of the thyroid follicle. The peripheral blood Tregs expressed minimal levels of Tg, and low levels of Tg could effectively induce peripheral blood Tregs to express Tg, which was independent of thyrotropin simulation. Furthermore, the Tg secreted freely from thyroid Tregs that negatively regulated some thyroid-related genes expression. Our results revealed that the thyroid Tregs was a distinct population of Tregs, which expressed high level of Tg. The thyroid Tregs regulate thyroid function by Tg that is paracrine from the cells.