Xin-Ji-Er-Kang Alleviates Myocardial Infarction-Induced Cardiovascular Remodeling in Rats by Inhibiting Endothelial Dysfunction.

The present study was designed to elucidate the beneficial effects of XJEK on myocardial infarction (MI) in rats, especially through the amelioration of endothelial dysfunction (ED). 136 Sprague-Dawley rats were randomized into 13 groups: control group for 0wk (n = 8); sham groups for 2, 4, and 6 weeks (wk); MI groups for 2, 4, and 6 wk; MI+XJEK groups for 2, 4, and 6w k; MI+Fosinopril groups for 2, 4, and 6 wk (n = 8~10). In addition, 8 rats were treated for Evans blue staining and Tetrazolium chloride (TTC) staining to determine the infarct size. Cardiac function, ECG, and cardiac morphological changes were examined. Colorimetric analysis was employed to detect nitric oxide (NO), and enzyme-linked immunosorbent assay (ELISA) was applied to determine N-terminal probrain natriuretic peptide (NT-ProBNP), endothelin-1 (ET-1), angiotensin II (Ang II), asymmetric dimethylarginine (ADMA), tetrahydrobiopterin (BH4), and endothelial NO synthase (eNOS) content. The total eNOS and eNOS dimer/(dimer+monomer) ratios in cardiac tissues were detected by Western blot. We found that administration of XJEK markedly ameliorated cardiovascular remodeling (CR), which was manifested by decreased HW/BW ratio, CSA, and less collagen deposition after MI. XJEK administration also improved cardiac function by significant inhibition of the increased hemodynamic parameters in the early stage and by suppression of the decreased hemodynamic parameters later on. XJEK also continuously suppressed the increased NT-ProBNP content in the serum of MI rats. XJEK improved ED with stimulated eNOS activities, as well as upregulated NO levels, BH4 content, and eNOS dimer/(dimer+monomer) ratio in the cardiac tissues. XJEK downregulated ET-1, Ang II, and ADMA content obviously compared to sham group. In conclusion, XJEK may exert the protective effects on MI rats and could continuously ameliorate ED and reverse CR with the progression of MI over time.

Xin-Ji-Er-Kang ameliorates kidney injury following myocardial infarction by inhibiting oxidative stress via Nrf2/HO-1 pathway in rats.

AIM: Cardiovascular diseases, such as coronary heart disease and myocardial infarction (MI) are currently considered as the leading causes of death and disability. The aim of the present study is to investigate the effects of Xin-Ji-Er-Kang (XJEK) on kidney injury and renal oxidative stress. In addition, the associated mechanism involved in these processes was examined in an MI model, and particularly focused on the nuclear factor erythroid 2-related factor (NRF2)/heme oxygenase-1 (HO-1) pathway. MATERIALS AND METHODS: A total of 138 Sprague-Dawley rats were used in the present study. The control group was designated as 0 wk (n = 8). A total of 3 phases (2, 4, 6 wk) of administration were used in the sham-operated groups (sham, n = 10), MI groups (MI, n = 10), MI + XJEK groups (XJEK, n = 10) and MI + fosinopril groups (fosinopril, n = 10). Additional 10 rats were used to evaluate the infarct area. At 2, 4 or 6 wk post-MI, the hemodynamic parameters were monitored, the rats were sacrificed, then blood, heart and renal tissues were collected for furtherly analysis. RESULTS: The results indicated that XJEK administration continuously ameliorated renal hypertrophy index, blood urea nitrogen and cystatin C concentrations. XJEK further improved post-MI cardiac function by limiting scar formation and caused a downregulation in the hemodynamic parameters at the end of 2 and 4 wk. The hemodynamic parameters were upregulated after 6 wk treatment with XJEKcompared with those noted in the MI groups. Similarly, XJEK treatment for 2 wk potentiated Nrf2 nuclear translocation and HO-1 expression and inhibited the deficiency of nuclear Nrf2 and HO-1 at 6 wk post-MI compared with that of the MI groups, indicating the attenuation of the renal oxidative stress condition. The levels of malondialdehyde and angiotensin II (Ang II) in plasma and renal tissues, as well as the levels of aldosterone, 8-hydroxydeoxyguanosine, angiotensin II type 1 receptor and NADPH Oxidase-4 in the kidney tissue significantly decreased following XJEK treatment for 6 wk. In addition, the XJEK treatment groups revealed a significant upregulation in the activity of superoxide dismutase and in the total antioxidant capacity activity compared with those noted in the corresponding MI groups. CONCLUSION: These results demonstrated that progressive nephropathy in MI rats was associated with intrarenal activation of the renin-angiotensin-aldosterone system. Concomitantly, this process was associated with oxidative stress and impaired Nrf2 activation. The improvement in the severity of nephropathy by XJEK in this model may be associated with the reversal of these abnormalities.

Protective effect of Xin-Ji-Er-Kang on cardiovascular remodeling in high-salt induced hypertensive mice: Role ofoxidative stress and endothelial dysfunction.

BACKGROUND: Xin-Ji-Er-Kang (XJEK) is a Chinese herbal formula that has beenreported to exert effective protection against cardiovascular diseases, such as hypertension and myocarditis. OBJECTIVE: The aim of the present study was to investigate the effect of XJEK on high-salt-induced hypertensive mice and its possible mechanism. METHODS: The model of hypertension was established through a high-salt diet. Sixty male Kunming mice were randomized into six groups, namely the Control, Model, Low-dose XJEK, Middle-dose XJEK, High-dose XJEK and Fosinopril groups (n=10 per group). Different steady interventions were given to each group: 0.9% Sodium chloride was added to the diet of the Control group and 8% sodium chloride to the diet of the other five groups from the very beginning. An additional 4, 8 and 12 g/kg/day XJEK were intragastrically administered to the Low-dose, Middle-dose and High-dose XJEK groups, respectively, and 2 mg/kg/day fosinopril to the fosinopril group, from the start of week 5. Systolic blood pressure (SBP) was measured weekly from weeks 1 to 8 using the tail-cuff method. At the end of week 8, left ventricular (LV) systolic pressure, LV end-diastolic pressure and rate of rise of LV pressure were examined using a TransonicScisense catheter (Transonic Systems Inc,Ithaca, NY,USA). Endothelium-dependent relaxations induced by acetylcholine were observed in an isolated thoracic aorta ring. Serum and heartsweresampled for the measurement of the following indexes:Serum nitric oxide (NO), superoxide dismutase (SOD) activity and malondialdehyde (MDA) content (determined by colorimetricanalysis); serum angiotensin II(Ang II), endothelin-1, endothelial NO synthase (eNOS), asymmetric dimethylarginine (ADMA), tetrahydrobiopterin (BH4) concentration and l-arginine (determined by enzyme-linked immunosorbent assay); heart to body weight (HW/BW) ratio; myocardial morphological change (determined by HE and VG staining); myocardial eNOS expression (determined by immunofluorescence), and myocardial endothelin receptor A (ETA) expression (determined by western blotting). RESULTS: Statistical data showed that the HW/BW ratio was significantly decreased in the drug treatment group. XJEK treatment could improve the heart systolic and diastolic function and ameliorate hemodynamic parameters and vascular remodeling indexes. Colorimetric results showed that, compared with the model group, XJEK increased serum SOD, NOlevels, and decreased those of serum MDA and Ang II. XJEK reverted changes in cardiac pathology, decreased the myocardial cross-sectional area, collagen volume fraction and perivascular collagen area and improved endothelial dysfunction (ED) by promoting eNOS activity, enhancing NO bioavailability, increasing the expression of BH4 and decreasing ETA content. In addition, treatment with XJEK decreased ADMA content in the myocardium. CONCLUSION: In conclusion, XJEK mitigates cardiac remodeling in high-salt-induced hypertensive mice. The potential mechanism involves improved oxidative stress and endothelial dysfunction, independently of ameliorating BP.

Effects of Xin-Ji-Er-Kang on heart failure induced by myocardial infarction: Role of inflammation, oxidative stress and endothelial dysfunction.

BACKGROUND: Xin-Ji-Er-Kang (XJEK) is a Chinese herbal formula, which has been reported to exert effective protection on cardiovascular diseases like hypertension and myocarditis. PURPOSE: To elucidate the protective effects of XJEK on heart failure (HF) induced by myocardial infarction (MI) through the amelioration of inflammation, oxidative stress (OS) and endothelial dysfunction(ED). MATERIALS AND METHODS: Fifty-seven male KM mice were randomized into the following six groups (n = 9-10 for each): control group, model group, MI+XJEK low dose group(XJEKL) group, MI+XJEK middle dose group(XJEKM), MI+XJEK high dose group(XJEKH), and MI+fosinopril group (positive control group). After treatment for four weeks, electrocardiography (ECG) and haemodynamics were recorded. Serum and tissues were collected for further analysis. Endothelium-dependent relaxation induced by acetylcholine was assessed in isolated thoracic aorta ring experiment. Hematoxylin and eosin (HE) and Van Gieson (VG) staining were used to detect the pathological changes of heart and thoracic aorta. Colorimetric analysis was employed to determine serum nitric oxide level (NO), malondialdehyde (MDA) concentration and superoxide dismutase (SOD) activity. ELISA was used to detect serum B-type natriuretic peptide (BNP) and serum inflammatory cytokines, as well as endothelial NO synthetase (eNOS), angiotensinII (Ang II) and endothelin-1(ET-1) concentration in both serum and cardiac tissues. Immunohistochemistry and Western blotting (WB) were employed to detect eNOS and inflammatory cytokine expressions in cardiac tissues. RESULTS: XJEK administration markedly ameliorated cardiac dysfunction and abnormal ECG manifested by decreased weight/body weight (HW/BW) ratio, BNP and remedied hypertrophy of cardiomyocytes and deposition of collagen, which might be in part attributed to the increased SOD and decreased MDA in serum. Furthermore, XJEK administration improved ED with boosted eNOS activities in serum and cardiac tissues, as well as up-regulated NO levels in serum, down-regulated Ang II and ET-1 content in serum and cardiac tissues. Lastly, protein expression of pro-inflammation cytokines significantly decreased, and anti-inflammatory cytokine was significantly enhanced in serum and cardiac tissues compared to model group. CONCLUSION: XJEK may exert beneficial effects on HF induced by MI in mice, and the underlying mechanism may be attributable to the amelioration of ED, anti-OS and anti-inflammation effects.