RESUMO
ObjectiveTo observe the therapeutic effect of Yiyuan Qiwei pills (YYQW) on diabetes mellitus-induced induced erectile dysfunction (DMED) in rats and explore its regulation on the nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) signaling pathway. MethodFifty-five healthy SD male rats of clean grade aged 2-3 months underwent intraperitoneal injection of streptozotocin (STZ) to induce the DMED model, and another 10 healthy SD male rats of clean grade aged 2-3 months were assigned to the control group. The model rats were randomly divided into a model group, a sildenafil group (5 mg·kg-1, ig), and low-, medium-, and high-dose YYQW groups (1.5, 3.0, 6.0 g·kg-1, ig). The rats in the model group and the control group were given normal saline by gavage at 10 mL·kg-1, once a day for two months. After intervention, the penile erectile function of rats in each group was measured by a pressure detection system. The pathological changes and ultrastructure of penile corpus cavernosum were observed by hematoxylin-eosin (HE) staining and transmission electron microscopy, respectively. The level of NO in the corpus cavernosum was detected by nitrate reductase. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of cGMP and advanced glycation end products (AGEs). Real-time quantitative polymerase chain reaction (Real-time PCR) was used to detect the mRNA expression of endothelial nitric oxide synthase (eNOS), neurogenic nitric oxide synthase (nNOS), total nitric oxide synthase (NOS), and phosphodiesterase type5 (PDE5) in rat penile tissues. The expression of above proteins was detected by Western blot. ResultCompared with the control group, the model group showed decreased intracavernous pressure (ICP), NO, and cGMP levels, reduced mRNA and protein expression of nNOS and NOS, and increased PDE5 mRNA and protein expression (P<0.05). Compared with the model group, the sildenafil group and the YYQW groups displayed increased ICP, NO, and cGMP levels, elevated mRNA and protein expression levels of nNOS and NOS, and reduced PDE5 mRNA and protein expression levels (P<0.05). There were no pathological changes in the tissues and cell ultrastructure of the corpus cavernosum in the control group, while serious pathological changes were observed in the model group. Additionally, the sildenafil group and the YYQW groups were superior to the model group, the optimal effect was observed in the high-dose YYQW group. ConclusionYYQW can improve the penile erectile function of DMED rats and reduce the pathological damage of corpus cavernosum. The mechanism may be related to the promotion of nNOS and NOS expression, the inhibition of PDE5 expression, and the activation of the NO/cGMP signaling pathway.
RESUMO
ObjectiveTo observe the therapeutic effect of Yiyuan Qiwei pills (YYQW) on diabetes mellitus-induced induced erectile dysfunction (DMED) in rats and explore its regulation on the nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) signaling pathway. MethodFifty-five healthy SD male rats of clean grade aged 2-3 months underwent intraperitoneal injection of streptozotocin (STZ) to induce the DMED model, and another 10 healthy SD male rats of clean grade aged 2-3 months were assigned to the control group. The model rats were randomly divided into a model group, a sildenafil group (5 mg·kg-1, ig), and low-, medium-, and high-dose YYQW groups (1.5, 3.0, 6.0 g·kg-1, ig). The rats in the model group and the control group were given normal saline by gavage at 10 mL·kg-1, once a day for two months. After intervention, the penile erectile function of rats in each group was measured by a pressure detection system. The pathological changes and ultrastructure of penile corpus cavernosum were observed by hematoxylin-eosin (HE) staining and transmission electron microscopy, respectively. The level of NO in the corpus cavernosum was detected by nitrate reductase. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of cGMP and advanced glycation end products (AGEs). Real-time quantitative polymerase chain reaction (Real-time PCR) was used to detect the mRNA expression of endothelial nitric oxide synthase (eNOS), neurogenic nitric oxide synthase (nNOS), total nitric oxide synthase (NOS), and phosphodiesterase type5 (PDE5) in rat penile tissues. The expression of above proteins was detected by Western blot. ResultCompared with the control group, the model group showed decreased intracavernous pressure (ICP), NO, and cGMP levels, reduced mRNA and protein expression of nNOS and NOS, and increased PDE5 mRNA and protein expression (P<0.05). Compared with the model group, the sildenafil group and the YYQW groups displayed increased ICP, NO, and cGMP levels, elevated mRNA and protein expression levels of nNOS and NOS, and reduced PDE5 mRNA and protein expression levels (P<0.05). There were no pathological changes in the tissues and cell ultrastructure of the corpus cavernosum in the control group, while serious pathological changes were observed in the model group. Additionally, the sildenafil group and the YYQW groups were superior to the model group, the optimal effect was observed in the high-dose YYQW group. ConclusionYYQW can improve the penile erectile function of DMED rats and reduce the pathological damage of corpus cavernosum. The mechanism may be related to the promotion of nNOS and NOS expression, the inhibition of PDE5 expression, and the activation of the NO/cGMP signaling pathway.