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Studies have shown that metabolic syndrome is associated with reproductive problems. Women with metabolic syndrome, characterized by hyperinsulinemia, have common ovarian dysfunction, but the mechanism remains elusive. The aim of this research is to explore the effects of high levels of insulin on ovary function during early pregnancy. Mice in the high insulin-exposed group were given a subcutaneous injection of human recombinant insulin. After insulin treatment, changes in various hormones were tested using ELISA kits which showed hormones secreted by the ovary were significantly altered in the insulin group. TUNEL staining showed less TUNEL-positive cells in the insulin group. A significant decrease in Bax and an increase in Bcl2 in the ovary were found in the insulin group by immunohistochemical studies. Western blotting showed the expressions of apoptosis related proteins in the ovaries from the insulin group were obviously altered. In addition, expression of p-Akt proteins in the ovaries from the insulin group was significantly upregulated. Moreover, the Akt inhibitor LY294002 reversed the anti-apoptotic effects of high insulin in the ovary tissues in early pregnancy mice. All of these results showed that insulin impaired ovarian function during early pregnancy and ovarian apoptosis is imbalanced under the role of insulin. The PI3K/AKT signalling pathway might participate in this process., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: This study aimed to construct a working model for detecting the mitochondrial damage and expression of Mfn2. It furthermore explored the pathogenesis of premature ovarian failure (POF) induced by cisplatin., Method: Forty young female mice were divided randomly into two groups. The first was the treatment group intraperitoneally administered cisplatin (1.5mg/kg). The untreated control group was likewise injected with physiological saline for 10 days. One month later, we observed the ovarian weight and morphological changes, particularly the development of follicles and concentration of sex hormones. Immunohistochemistry and western blotting were used to measure the two groups. We later evaluated ovarian cell apoptosis with TUNEL and analyzed Bcl-2 and Bax levels. We used transmission electron microscopy in order to observe the ultrastructure of ovarian cells. The phosphomolybdic acid colorimetric method was used to measure the ATP content in the ovarian tissue. Finally, the mitochondrial membrane potential of ovarian cells was detected with JC-1 dye., Results: The cisplatin resulted in a decline of body weight, reduced ovarian weight significantly, and resulted in disorders of the extrous cycle. The follicles' number decreased within the tissue's stromal hyperplasia. Moreover, E2 levels were reduced, and elevated gonadotropin levels were observed. However, Mfn2 was present in the cell's cytoplasm in both groups. Nevertheless, the Mfn2 levels and the expression of Bcl-2 were significantly decreased (p<0.05), but the expression of Bax and the apoptosis index (AI) was increased. In addition, the ATP levels (35.2 ± 5.7 μmol/g) of the control group were significantly higher (13.5 ± 3.8 μmol/g). Lastly, an obvious impairment of mitochondrial function and structure was observed., Conclusion: The intreperitoneal injection of cisplatin, when administered for 10 days, establishes a POF model. Thus, the above results suggest that lower expression of Mfn2 may be involved in the mechanism of premature ovarian failure by affecting both the mitochondria's energy metabolism and its apoptosis. This decides the termination of the follicles' development.

Chronic exposure to solar UV irradiation leads to photoaging, immunosuppression, and ultimately carcinogenesis. Cellular senescence is thought to play an important role in tumor suppression and apoptosis resistance. However, the relationships among stress-induced premature senescence (SIPS), tumorigenesis and apoptosis induced by UVB remain unknown. We developed a model of UVB-induced premature senescence in human skin fibroblasts (HSFs). After five repeated subcytotoxic UVB exposures at a dose of 10 mJ/cm2, the following biomarkers of senescence were markedly present: senescence-associated beta-galactosidase (SA beta-gal) activity, growth arrest, and the overexpression of senescence-associated genes. Firstly, there was an increase in the proportion of cells positive for SA beta-gal activity. Secondly, there was a loss of replicative potential as assessed by MTT assay. FACS analysis showed that UVB-stressed HSFs were blocked mostly in the G1 phase of the cell cycle, and replicative senescence, and protein expression of p53, p21(WAF-1) and p16(INK-4a) increased significantly. Thirdly, the mRNA levels of three senescence-associated genes, fibronectin, osteonectin and SM22, also increased. A real time PCR array to investigate the mRNA expression of p53-related genes involved in growth arrest, apoptosis and tumorigenesis indicated that p53, p21, p19, Hdm2, and Bax were up-regulated, and bcl, HIF-1alpha and VEGF were down-regulated. Collectively, our data suggest that UVB-induced SIPS plays an important role in p53-related apoptosis resistance and tumor suppression activity.

3-n-Butylphthalide (NBP), one of the chemical constituents of celery oil, is used for the treatment of many central nervous system diseases, including Parkinson's disease, Alzheimer's disease and cerebral ischemia. NBP showed potent neuroprotective effects by decreasing oxidative damage, inhibiting inflammatory responses, improving mitochondrial function, and reducing neuronal apoptosis. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]