Ginsenoside Rb1 prevents age-related endothelial senescence by modulating SIRT1/caveolin-1/enos signaling pathway.

Background: Advancing age is one of the independent risk factors for cardiovascular disorders. The Compendium of Materia Medica, a classic book on traditional Chinese medicine, states that ginseng "harmonizes the five internal organs, calming the spirit and prolonging the years of life." Considered one of the primary bioactive compounds derived from Panax ginseng, ginsenoside Rb1 (g-Rb1) has been scientifically suggested to possess anti-senescence efficacy. More research is needed to explore the vascular pharmacological activity and potential clinical application value of g-Rb1. Aims of the study: Our previous study demonstrated that g-Rb1 could mitigate cellular senescence via the SIRT1/eNOS pathway. This study was performed to explore the exact mechanisms by which g-Rb1 modulates the SIRT1/eNOS pathway. Materials and methods: We used human primary umbilical vein endothelial cells (HUVECs) to establish a replicative ageing model. Real-time (RT‒PCR), western blotting, small interfering RNA (siRNA), and immunoprecipitation were conducted to detect the effect of g-Rb1 on the SIRT1/caveolin-1/eNOS axis. Results: G-Rb1 increased NO production and alleviated replicative senescence of HUVECs. The application of g-Rb1 elevated the mRNA and protein abundance of both SIRT1 and eNOS while concomitantly suppressing the expression of caveolin-1. Inhibition of SIRT1 and eNOS by siRNAs suppressed the anti-senescence function of g-Rb1, while caveolin-1 siRNA could enhance it. G-Rb1 decreased the acetylation level of caveolin-1 and increased NO production, which was suppressed by SIRT1 siRNA. Both g-Rb1 and caveolin-1 siRNA could reduce the acetylation level of eNOS and increase NO production. Conclusion: G-Rb1 prevents age-related endothelial senescence by modulating the SIRT1/caveolin-1/eNOS signaling pathway.

Ginsenoside Rb1 Ameliorates Age-Related Myocardial Dysfunction by Regulating the NF-[Formula: see text]B Signaling Pathway.

Age-related myocardial dysfunction is a very large healthcare burden. Here, we aimed to investigate whether ginsenoside Rb1 (Rb1) improves age-related myocardial dysfunction and to identify the relevant molecular mechanism. Young mice and aged mice were injected with Rb1 or vehicle for 3 months. Then, their cardiac function was inspected by transthoracic echocardiography. Serum and myocardium tissue were collected from all mice for histological or molecular expression analyses, including aging-related proteins, markers relevant to fibrosis and inflammation, and markers indicating the activation of the nuclear factor-kappa B (NF-[Formula: see text]B) pathway. Compared with the control condition, Rb1 treatment significantly increased the ejection fraction percentage and significantly decreased the internal diameter and volume of the left ventricle at the end-systolic and end-diastolic phases in aged mice. Rb1 treatment reduced collagen deposition and collagen I, collagen III, and transforming growth factor-[Formula: see text]1 protein expression levels in aged hearts. Rb1 also decreased the aging-induced myocardial inflammatory response, as measured by serum or myocardial interleukin-6 and tumor necrosis factor-[Formula: see text] levels. Furthermore, Rb1 treatment in aged mice increased cytoplasmic NF-[Formula: see text]B but decreased nuclear NF-[Formula: see text]B, which indicated the suppression of the NF-[Formula: see text]B signaling pathway by regulating the translocation of NF-[Formula: see text]B. Rb1 could alleviate aging-related myocardial dysfunction by suppressing fibrosis and inflammation, which is potentially associated with regulation of the NF-[Formula: see text]B signaling pathway.

Ginsenoside Rb1 Alleviates Oxidative Low-Density Lipoprotein-Induced Vascular Endothelium Senescence via the SIRT1/Beclin-1/Autophagy Axis.

Oxidative low-density lipoprotein (ox-LDL) induces endothelium senescence and promotes atherosclerosis. Ginsenoside Rb1 (gRb1) has been proved to protect human umbilical vein cells (HUVECs), but its effect on ox-LDL-induced endothelium senescence and the underlying mechanism remains unknown. This study is to explore the involvement of the SIRT1/Beclin-1/autophagy axis in the effect of gRb1 on protecting endothelium against ox-LDL-induced senescence. Hyperlipidemia of Sprague Dawley rats was induced by high-fat diet, and gRb1 was intraperitoneal injected. A senescence model of HUVECs induced by ox-LDL was also established. The results showed that gRb1 alleviated hyperlipidemia-induced endothelium senescence and ox-LDL-induced HUVECs senescence. GRb1 also restored the reductions in SIRT1 and autophagy, which were involved in the anti-senescence effects. Beclin-1 acetylation was reduced, and the correlation between SIRT1 and Beclin-1 was increased by gRb1. Results of our study demonstrated the anti-senescence function of gRb1 against hyperlipidemia in the endothelium, and the underlying mechanism involves the SIRT1/Beclin-1/autophagy axis.

Ginsenoside Rb1 prevents H2O2-induced HUVEC senescence by stimulating sirtuin-1 pathway.

PURPOSES: We have previously reported that Ginsenoside Rb1 may effectively prevent HUVECs from senescence, however, the detailed mechanism has not demonstrated up to now. Recent studies have shown that sirtuin-1 (Sirt1) plays an important role in the development of endothelial senescence. The purpose of this study was to explore whether Sirt1 is involved in the action of Ginsenoside Rb1 regarding protection against H2O2-induced HUVEC Senescence. METHODS AND RESULTS: Senescence induced by hydrogen peroxide (H2O2) in human umbilical vein endothelial cells (HUVECs) was examined by analyzing plasminogen activator inhibitor-1 (PAI-1) expression, cell morphology, and senescence-associated beta-galactosidase (SA-ß-gal) activity. The results revealed that 42% of control-treated HUVECs were SA-ß-gal positive after treatment by 60 µmol/L H2O2, however, this particular effect of H2O2 was decreased more than 2-fold (19%) in the HUVECs when pretreated with Rb1 (20 µmol/L) for 30 min. Additionally, Rb1 decreased eNOS acetylation, as well as promoted more NO production that was accompanied by an increase in Sirt1 expression. Furthermore, upon knocking down Sirt1, the effect of Rb1 on HUVEC senescence was blunted. CONCLUSIONS: The present study indicated that Ginsenoside Rb1 acts through stimulating Sirt1 in order to protect against endothelial senescence and dysfunction. As such, Sirt1 appears to be of particular importance in maintaining endothelial functions and delaying vascular aging.

Use of wave intensity analysis of carotid arteries in identifying and monitoring left ventricular systolic function dynamics in rabbits.

Wave intensity analysis (WIA) of the carotid artery was conducted to determine the changes that occur in left ventricular systolic function after administration of doxorubicin in rabbits. Each randomly selected rabbit was subject to routine ultrasound, WIA of the carotid artery, cardiac catheterization and pathologic examination every week and was followed for 16 wk. The first positive peak (WI1) of the carotid artery revealed that left ventricular systolic dysfunction occurred earlier than conventional indexes of heart function. WI1 was highly, positively correlated with the maximum rate of rise in left ventricular pressure in cardiac catheterization (r = 0.94, p < 0.01) and moderately negatively correlated with the apoptosis index of myocardial cells, an indicator of myocardial damage (r = -0.69, p < 0.01). Ultrasound WIA of the carotid artery sensitively reflects early myocardial damage and cardiac function, and the result is highly consistent with cardiac catheterization findings and the apoptosis index of myocardial cells.

Ginsenoside Rb1 reverses H2O2-induced senescence in human umbilical endothelial cells: involvement of eNOS pathway.

OBJECTIVE: Senescence of endothelial cells has been implicated in endothelial dysfunction and atherogenesis. This study investigated the effects of Rb1, a major ginsenoside in ginseng, on H2O2-induced senescence in primary human umbilical vein endothelial cells (HUVECs). METHODS AND RESULTS: Real-time PCR and Western blot were used to detect the mRNA and protein expression, respectively. H2O2 (40∼100 µmol/L) effectively increased SA-ß-gal activity and PAI-1 mRNA levels, two important senescence related biomarkers, in HUVECs, which were dramatically inhibited by Rb1 pre-incubation. Furthermore, Rb1 administration reversed the H2O2-decreased protein and mRNA levels of eNOS and its phosphorylation at Ser-1177, and the increased eNOS phosphorylation at Thr-495. As a result, Rb1 pretreatment restored the NO generation, as assayed by nitrate reductase method. However, pretreatment with L-NAME, a NOS inhibitor, abolished all the inhibitory effects of Rb1 on senescence. Importantly, Rb1 modulated the H2O2-altered caveolin-1 and pAkt, two most important regulators of eNOS expression and activity, in HUVECs. CONCLUSIONS: We showed that Rb1 effectively protects HUVECs from senescence through eNOS modulation.

Rb1 protects endothelial cells from hydrogen peroxide-induced cell senescence by modulating redox status.

Senescence of endothelial cells has been proposed to play an important role in endothelial dysfunction and atherogenesis. In the present study we aimed to investigate whether ginsenoside Rb1, a major constituent of ginseng, protects endothelial cells from H(2)O(2)-induced endothelial senescence. While H(2)O(2) induced premature senescent-like phenotype of human umbilical vein endothelial cells (HUVECs), as judged by increased senescence-associated ß-galactosidase (SA-ß-gal) activity, enlarged, flattened cell morphology and sustained growth arrest, our results demonstrated that Rb1 protected endothelial cells from oxidative stress induced senescence. Mechanistically, we found that Rb1 could markedly increase intracellular superoxide dismutase (Cu/Zn SOD/SOD1) activity and decrease the malondialdehyde (MDA) level in H(2)O(2)-treated HUVECs, and suppress the generation of intracellular reactive oxygen species (ROS). Consistent with these findings, Rb1 could effectively restore the protein expression of Cu/Zn SOD, which was down-regulated in H(2)O(2) treated cells. Taken together, our data demonstrate that Rb1 exhibits antioxidant effects and antagonizes H(2)O(2)-induced cellular senescence.

[Effect of the sera of rabbits fed with Tongxinluo on MMP-9 and TIMP-1 expression and secretion in U937 monocyte-derived macrophages].

OBJECTIVE: To investigate the effect of the sera of rabbits fed with Tongxinluo on the expression and secretion of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in U937 monocyte-derived macrophages. METHODS: Atherosclerosis was induced in rabbits by high-cholesterol feeding, and the serum was obtained from the rabbits after administration of the aqueous solution of Tongxinluo or simvastatin by gavage. U937 monocyte-derived macrophages were incubated with the sera at different concentrations for 24 hours, and the changes in MMP-9 and TIMP-1 gene expression and secretion were detected by RT-PCR and enzyme-linked immunosorbent assay, respectively. RESULTS: The serum of rabbits fed with Tongxinluo concentration-dependently inhibited the expression and secretion of MMP-9 in U937 macrophages, but did not affect TIMP-1 expression or secretion. CONCLUSION: Tongxinluo may stabilize the atherosclerotic plaques by inhibiting the expression and secretion of MMP-9.

Clinical significance of detection of carotid artery plaque in patients with acute coronary syndrome.

OBJECTIVE: To study the intima-media thickness (IMT), plaque score in the carotid artery of patients with acute coronary syndrome (ACS) and the relationship between high-sensitivity C-reactive protein (hs-CRP) and the plaque score. METHODS: Using high-resolution ultrasonic instrument, IMT and the plaque score in the carotid artery were detected in 30 patients with ACS, 29 patients with stable angina pectoris SAP and 17 control subjects, in addition to the measurement of hs-CRP. RESULTS: Compared with SAP and control groups, IMT, total plaque score, soft and hard plaque scores in the carotid artery in ACS group were significantly increased (P<0.001). Hs-CRP (4.336+/-1.334 mg/L) in ACS group were significantly increased (P<0.001) as compared with that in SAP group (2.205+/-0.458 mg/L) and control group (1.625+/-0.434 mg/L). Hs-CRP had positive relationship with the IMT, whole plaque score, soft and hard plaque scores in the carotid artery, respectively. CONCLUSION: IMT, total plaque score, soft and hard plaque scores in the carotid artery in ACS group are significantly increased, and hs-CRP is positively related to IMT, total plaque score, soft and hard plaque scores in the carotid artery, respectively.