Higenamine attenuates cardiac fibroblast abstract and fibrosis via inhibition of TGF-ß1/Smad signaling.

RATIONALE: Higenamine (HG), is one of the main active components in many widely used Chinese herbs, and a common ingredient of health products in Europe and North America. Several groups, including our own, have previously shown the beneficial effects of HG against cardiomyocyte death during acute ischemic damage. However, the effect of HG on chronic cardiac remodeling, such as cardiac fibrosis, remains unknown. OBJECTIVE: Herein, we aim to investigate the role of HG in cardiac fibrosis in vivo as well as its cellular and molecular mechanisms. METHODS AND RESULTS: Chronic pressure overload with transverse aortic constriction (TAC) significantly increased cardiac hypertrophy, fibrosis, and cardiac dysfunction in mice, which were significantly attenuated by HG. Consistently, cardiac fibrosis induced by the chronic infusion of isoproterenol (ISO), was also significantly reduced by HG. Interestingly, our results showed that HG had no effect on adult mouse CM hypertrophy in vitro. However, HG suppressed the activation of cardiac fibroblasts (CFs) in vitro. Furthermore, TGF-ß1-induced expression of ACTA2, a marker of fibroblast activation, was significantly suppressed by HG. Concomitantly, HG inhibited TGF-ß1-induced phosphorylation of Smad2/3 in CFs. HG also reduced the expression of extracellular matrix molecules such as collagen I and collagen III. To our surprise, the inhibitory effect of HG on CFs activation was independent of the activation of the beta2 adrenergic receptor (ß2-AR) that is known to mediate the effect of HG on antagonizing CMs apoptosis. CONCLUSION: Our findings suggest that HG ameliorates pathological cardiac fibrosis and dysfunction at least partially by suppressing TGF-ß1/Smad signaling and CFs activation.

Vinpocetine Attenuates Pathological Cardiac Remodeling by Inhibiting Cardiac Hypertrophy and Fibrosis.

PURPOSE: Pathological cardiac remodeling, characterized by cardiac hypertrophy and fibrosis, is a pathological feature of many cardiac disorders that leads to heart failure and cardiac arrest. Vinpocetine, a derivative of the alkaloid vincamine, has been used for enhancing cerebral blood flow to treat cognitive impairment. However, its role in pathological cardiac remodeling remains unknown. The aim of this study is to examine the effect of vinpocetine on pathological cardiac remodeling induced by chronic stimulation with angiotensin II (Ang II). METHODS: Mice received Ang II infusion via osmotic pumps in the presence of vehicle or vinpocetine. Cardiac hypertrophy and fibrosis were assessed by morphological, histological, and biochemical analyses. Mechanistic studies were carried out in vitro with isolated mouse adult cardiac myocytes and fibroblasts. RESULTS: We showed that chronic Ang II infusion caused cardiac hypertrophy and fibrosis, which were all significantly attenuated by systemic administration of vinpocetine. In isolated adult mouse cardiomyocytes, vinpocetine suppressed Ang II-stimulated myocyte hypertrophic growth. In cultured cardiac fibroblasts, vinpocetine suppressed TGFß-induced fibroblast activation and matrix gene expression, consistent with its effect in attenuating cardiac fibrosis. The effects of vinpocetine on cardiac myocyte hypertrophy and fibroblast activation are likely mediated by targeting cyclic nucleotide phosphodiesterase 1 (PDE1). CONCLUSIONS: Our results reveal a novel protective effect of vinpocetine in attenuating pathological cardiac remodeling through suppressing cardiac myocyte hypertrophic growth and fibroblast activation and fibrotic gene expression. These studies may also shed light on developing novel therapeutic agents for antagonizing pathological cardiac remodeling.

Higenamine protects ischemia/reperfusion induced cardiac injury and myocyte apoptosis through activation of ß2-AR/PI3K/AKT signaling pathway.

Cardiomyocyte apoptosis contributes to ischemic cardiac injury and the development of heart failure. Higenamine is a key component of the Chinese herb aconite root that has been prescribed for treating symptoms of heart failure for thousands of years in the oriental Asian countries. It has been shown that higenamine has anti-apoptotic effects in a few cell types including cardiomyocytes. However, the pharmacological target and molecular mechanism of higenamine in the heart are still not fully illustrated. Herein, we report that higenamine protected myocyte apoptosis and ischemia/reperfusion (I/R) injury through selective activation of beta2-adrenergic receptor (ß2-AR). In particular, we show that higenamine significantly reduced I/R-induced myocardial infarction in mice. In both primary neonatal rat and adult mouse ventricular myocytes, we show higenamine inhibited cell apoptosis and also reduced biochemical markers of apoptosis such as cleaved caspase 3 and 9. More importantly, we show that the anti-apoptotic effects of higenamine in cardiomyocytes were completely abolished by ß2-AR but not ß1-AR antagonism. Furthermore, we confirmed that higenamine attenuated I/R-induced myocardial injury and reduced cleaved caspases in a ß2-AR dependent manner in intact mouse hearts. Higenamine stimulated AKT phosphorylation and required PI3K activation for the anti-apoptotic effect in cardiomyocytes. These findings together suggest that anti-apoptotic and cardiac protective effects of higenamine are mediated by the ß2-AR/PI3K/AKT cascade.

Reverse engineering of free-form surface based on the closed-loop theory.

To seek better methods of measurement and more accurate model of reconstruction in the field of reverse engineering has been the focus of researchers. Based on this, a new method of adaptive measurement, real-time reconstruction, and online evaluation of free-form surface was presented in this paper. The coordinates and vectors of the prediction points are calculated according to a Bézier curve which is fitted by measured points. Final measured point cloud distribution is in agreement with the geometric characteristics of the free-form surfaces. Fitting the point cloud to a surface model by the nonuniform B-spline method, extracting some check points from the surface models based on grids and a feature on the surface, review the location of these check points on the surface with CMM and evaluate the model, and then update the surface model to meet the accuracy. Integrated measurement, reconstruction, and evaluation, with the closed-loop reverse process, established an accurate model. The results of example show that the measuring points are distributed over the surface according to curvature, and the reconstruction model can be completely expressed with micron level. Meanwhile, measurement, reconstruction and evaluation are integrated in forms of closed-loop reverse system.

Reevaluation of the effect of lamivudine therapy preoperative to prevent HBV recurrence after liver transplantation.

BACKGROUND: Hepatitis B virus (HBV) recurrence may result in hepatic insufficiency or dysfunction of liver grafts. This study was to reevaluate the preventive effect of lamivudine therapy pretransplant on HBV recurrence after liver transplantation with combined lamivudine and hepatitis B immunoglobulin (HBIG) as a prophylactic regimen. METHODS: This is a single-center, retrospective study of 122 liver transplant recipients operated on from January 2002 to September 2006 at our hospital. All subjects showed positive hepatitis B surface antigen (HBsAg) and HBV DNA in blood, without HBV mutation in YMDD at the time of liver transplantation. The protocol with combined lamivudine and HBIG for preventing HBV recurrence was used on the day of operation. The initial immunosuppression therapy was identical. After one year follow-up, the recipients were divided into 2 groups: patients without HBV recurrence (group I) and patients with HBV recurrence (group II). Preoperative lamivudine therapy and postoperative mycophenolate mofetil (MMF) and glucocorticoid therapy were analyzed using the Wilcoxon's test and Stepwise logistic regression method. RESULTS: In the HBV recurrence group, the duration of pre-transplant lamivudine administration was significantly longer than that in the without HBV recurrence group (Z=-4.424, P=0.000). The HBV recurrence rate was significantly higher in patients with preoperative lamivudine therapy than in patients without lamivudine therapy (X2=13.11, P=0.000); the risk of HBV recurrence increased by a 10.909-fold in patients with pre-transplant lamivudine therapy compared with that in patients without lamivudine therapy (OR=10.909; 95% CI for OR: 2.86-41.67). Seven (63.6%) of 11 HBV recurrence recipients had YMDD mutants. The duration of MMF or glucocorticoid was not different between the 2 groups (Z(MMF)=-1.453, P(MMF)=0.146; Z(Pre)=-0.795, P(Pre)=0.427). No significant difference was noted in the HBV recurrent rate in patients with MMF duration < or =6 and >6 months (X2=0.185, P=0.667), as it was in patients with prednisone therapy < or =3 and >3 months (X2=0.067, P=0.793). CONCLUSIONS: With the protocol of combined lamivudine and HBIG for preventing HBV recurrence in liver transplantation recipients, liver transplantation candidates with positive HBV DNA should not be subjected to preoperative administration of lamivudine. A high dose of HBIG during the ahepatic period and in the early stage of post-transplantation can fulfill the treatment target as a long-term lamivudine therapy before liver transplantation. Long-term preoperative lamivudine treatment may result in an earlier HBV mutation in YMDD and increase the HBV recurrence rate and risk in the first year after transplantation.