Effect of saponins extracted from Panax japonicas on inhibiting myocardial fibrosis by TGF-β1/Smad3 signaling pathway in aging rats / 中国中药杂志

To investigate the amelioration effect of saponins extracted from Panax japonicas (SPJ) on myocardial fibrosis in natural aging rats and its mechanisms, male SD rats aged 18 months were randomly divided into 3 groups (aging model group, low-dose SPJ group and high-dose SPJ group), with 10 rats in each group. SPJ groups were given SPJ at different doses (10, 60 mg·kg⁻¹·d⁻¹) consecutively for 6 months, meanwhile, aging model group was treated with the equal volume of saline for 6 months until 24 months old. Another 10 rats aged 6 month were used as young control group. The changes of myocardial morphological were observed by haematoxylin-eosin (HE) staining. Masson staining was used to observe the changes of collagen deposition in rat hearts. RT-PCR was used to detect the mRNA expression levels of myofibroblast marker α-SMA, collagen-related protein COL1α2, COL3α1 and matrix metalloproteinase MMP2, MMP9. Western blot was used to test the changes of the protein expressions of TGF-β1, p-Smad3, IL-1β and TNF-α in heart tissues. SPJ can effectively improve the arrangement of myocardial fibers, decrease inflammatory infiltration and reduce collagen deposition in aging rats. SPJ can effectively down-regulate the mRNA expression levels of COL1α2, COL3α1, α-SMA, MMP9, MMP2 and inhibit the protein expressions of TGF-β1, p-Smad3, TNF-α, IL-1β in the natural aging heart tissues. SPJ can effectively alleviate myocardial fibrosis in natural aging rats, and its mechanisms was related to the inhibition of the protein expressions of TGF-β1, p-Smad3 and the reduction of myocardial inflammation in rat hearts.

Effect of saponins extracted from Panax japonicus on inhibiting cardiomyocyte apoptosis by AMPK/Sirt1/NF-κB signaling pathway in aging rats / 中国中药杂志

To investigate the effects of saponins extracted from Panax japonicus(SPJ) on cardiomyocyte apoptosis in natural aging rats and explore its underlying mechanisms. SD male rats were randomly divided into four groups: young control group, natural aging group, SPJ low dose group and SPJ high dose group, with 10 rats in each group. The rats in natural aging group, SPJ low and high dose groups were respectively treated with normal saline, SPJ 10 and 60 mg•kg-1•d-1 from the beginning of 18 month-old, 6 days per week for 6 months till 24 month-old. Then the animals were sacrificed. Their myocardial morphology changes were observed by using haematoxylin-eoin(HE) staining; cardiomyocyte apoptosis was tested by using Tunel assays; and the protein expression levels of Bcl-2, Bax, IL-1β, TNF-α, AMPK, p-AMPK, Sirt1, and Ac-NF-κB p65 in myocardial tissues of rats were detected by Western blot. The results showed that SPJ could effectively improve the arrangement disorder of myocardial fibers, reduce the infiltration of inflammatory cells and inhibit cardiomyocyte apoptosis in natural aging rats. At the same time, SPJ could significantly inhibit the protein expression of Bax, IL-1β, TNF-α and Ac-NF-κB p65, and increase the expression of Bcl-2, Bcl-2/Bax, p-AMPK/AMPK and Sirt1 in the heart tissues of natural aging rats. SPJ can effectively inhibit cardiomyocyte apoptosis in natural aging rats, and its mechanisms may be related with the regulation of inflammatory reaction by AMPK/Sirt1/NF-κB signaling pathway.