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BackgroundPolycystic ovary syndrome (PCOS) is the most prevalent cause of anovulatory infertility and hyperandrogenism. Evidence favors insulin resistance and compensatory hyperinsulinemia as the predominant, perhaps primary, defects in PCOS. The use of insulin-sensitizing drugs has been shown to improve both the reproductive and the metabolic aspects of PCOS. Cinnamon has been found to have insulin sensitizing effect and improve menstrual cyclicity in women with PCOS. The aim of this study was to determine the effect and mechanism of cinnamon on PCOS using a dehydroepiandrosterone (DHEA) induced PCOS mouse model.MethodsPrepubertal C57BL/6 mice (age 25 days) were raised to developed into control group, DHEA group and DHEA plus cinnamon group for 20 days. The stages of the estrous cycle were determined based on vaginal cytology; metabolic characteristics were examined by intraperitoneal glucose tolerance test and insulin tolerance test, the serum levels of hormones (testosterone, insulin, LH, FSH, IGF-1, IGFBP-1) were checked using enzyme-linked immunosorbent assay (ELISA) method, the ovarian morphology was observed by stained with hematoxylin and eosin. IGF-1 and IGFBP-1 expression in ovary were detected by immunohistochemical stain.ResultsCinnamon restores the cyclicity and ovary morphology in PCOS mice model induced by DHEA. There are significant differences of serum level of total testosterone (0.033 ± 0.009 ng/ml), among control group, DHEA and cinnamon group (0.052 ± 0.011 ng/ml), and DHEA group (0.079 ± 0.015 ng/ml); There was an increasing tendency of serum FSH level from DHEA group (5.02 ± 0.31 ng/ml), DHEA and cinnamon group (5.81 ± 0.51 ng/ml), to control group (7.13 ± 0.74 ng/ml); and there was a decreasing trend of serum LH level from DHEA group (3.75 ± 0.57 ng/ml), DHEA and cinnamon group (1.35 ± 0.61 ng/ml), or control group (0.69 ± 0.34 ng/ml); serum insulin level is significantly higher in DHEA treated mice (1.61 ± 0.31 ng/ml) than control group (0.93 ± 0.19 ng/ml), or DHEA and cinnamon effect (1.27 ± 0.23 ng/ml) (p < 0.05). The DHEA group also has a higher serum IGF-1 level (0.35 ± 0.06 ng/ml) than control group (0.17 ± 0.04 ng/ml) or DHEA and cinnamon group (0.21 ± 0.05 ng/ml) (p < 0.05). While DHEA group has a lower IGFBP-1 level (5.5 ± 1.6 ng/ml) than control group (15.8 ± 2.1 ng/ml) or DHEA and cinnamon group (10.3 ± 2.5 ng/ml) (p < 0.05). Cinnamon also attenuates DHEA induced a higher IGF-1 and lower IGFBP-1 expression in ovary by immunohistochemistry.ConclusionsThese preliminary data suggest that cinnamon supplementation improves insulin resistance and may be a potential therapeutic agent for the treatment of PCOS.

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Protein kinases play an important role in regulating the response to abiotic stress in plant. CIPKs are plant-specific signal transducers, and some members have been identified. However, the precise functions of novel CIPKs still remain unknown. Here we report that HbCIPK2 is a positive regulator of salt and osmotic stress tolerance. HbCIPK2 was screened out of the differentially expressed fragments from halophyte Hordeum brevisubulatum by cDNA-AFLP technique, and was a single-copy gene without intron. Expression of HbCIPK2 was increased by salt, drought and ABA treatment. HbCIPK2 is mainly localized to the plasma membrane and nucleus. Ectopic expression of 35S:HbCIPK2 not only rescued the salt hypersensitivity in Arabidopsis mutant sos2-1, but also enhanced salt tolerance in Arabidopsis wild type, and exhibited tolerance to osmotic stress during germination. The HbCIPK2 contributed to the ability to prevent K + loss in root and to accumulate less Na + in shoot resulting in K + /Na + homeostasis and protection of root cell from death, which is consistent with the gene expression profile of HbCIPK2-overexpressing lines. These findings imply possible novel HbCIPK2-mediated salt signalling pathways or networks in H. brevisubulatum.