Lycium barbarum   polysaccharide attenuates cisplatin-induced apoptosis in ovary granulosa cells via alleviation of endoplasmic reticulum stress

Purpose: To investigate the effect of Lycium barbarum polysaccharide (LBP) on apoptosis of ovary granulose cells (GCs), as well as its underlying mechanism.
Methods: GCs were isolated from Sprague Dawley (SD) rats and divided into three groups: control group, model group (DDP) and LBP group. Cell morphology was observed by H & E staining under optical microscope. Expression of follicle stimulating hormone receptor (FSHR) was assessed by immunohistochemistry (IHC), while cell viability was assayed using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT). Apoptosis was determined by flow cytometry. Expressions of glucose-regulated protein 78(GRP78), C/EBP homologous protein (CHOP), caspase-3, Bax protein and B cell lymphoma-2(Bcl-2) were assayed by Western blot and qRT-PCR.
Results: Apoptosis index (37.6 ± 2.44 %) was significantly higher (p > 0.05) in DDP group than in the control group (14.3 ± 1.09 %), while mRNA levels and expressions of caspase-3, Bcl-2 and Bax increased significantly (p > 0.05). Expressions of GRP78 and CHOP in the DDP group were also higher than in the control group (p > 0.05). However, these effects were effectively blocked by co-incubation with LBP. Moreover, the DDP-induced increase in apoptosis index was dose-dependently and significantly lowered by LBP (p > 0.05).
Conclusion: LBP exerts protective effect on cisplatin-induced apoptosis in ovary granulosa cells by alleviating endoplasmic reticulum stress and regulating levels of apoptosis-related proteins. Thus, LBP has the potential for alleviating adverse effects induced by cisplatin in the treatment of ovary granulosa lesions.

Keywords
Cis-platin, Ovary granulosa lesions, Lycium barbarum polysaccharide, Endoplasmic reticulum stress, Apoptosis