Haemodynamic effects of chronic tetrandrine treatment in portal hypertensive rats

Tetrandrine ameliorated reperfusion injury of small bowel transplantation

PURPOSE

In small bowel transplantation, the bowel graft is susceptible to reperfusion injury. This study investigated the effects of tetrandrine, a bisbenzylisoquinoline alkaloid, on the development of intestinal reperfusion injury in small bowel transplantation in pigs.

MATERIALS AND METHODS

Pigs underwent small bowel transplantation and were treated with tetrandrine or a vehicle. Blood and small bowel specimens were harvested at 1, 3, and 24 hours after reperfusion. Histopathologic analysis of the small bowel was assessed for tissue damage. Serum levels of tumor necrosis factor-alpha, interleukin-1beta (IL-1beta), and IL-6 were measured by enzyme-linked immunosorbent assay. Reverse-transcriptase polymerase chain reaction analysis was performed to analyze the expression of proinflammatory cytokines, and immunohistochemical analysis was used to study the expression of intercellular adhesion molecule-1 (ICAM-1) in the small bowel. Myeloperoxidase staining detected neutrophil infiltration in the small bowel and the number of myeloperoxidase positively stained cells was counted.

RESULTS

Pigs receiving small bowel transplantation had elevated serum proinflammatory cytokine levels. The transplanted small bowel showed mucosal damage, increased expression of proinflammatory cytokines and ICAM-1, and prominent neutrophil infiltration. Tetrandrine administration reduced mucosal damage, serum and tissue proinflammatory cytokine levels, ICAM-1 expression, and neutrophil accumulation in the transplanted small bowel.

CONCLUSIONS

Tetrandrine reduced the reperfusion injury in porcine intestinal transplantation during the first 24 hours after the procedure.

Tetrandrine suppresses tumor growth and angiogenesis of gliomas in rats

Tetrandrine, a bisbenzylisoquinoline alkaloid, has antitumor effects against some cancers, but its effects on gliomas are unknown. In this study, we investigated the effects of tetrandrine on the growth and angiogenesis of rat RT-2 gliomas. We treated RT-2 glioma cells with tetrandrine and then measured cytotoxicity, apoptosis and expression of vascular endothelial growth factor (VEGF). We also examined the cytotoxic effect of tetrandrine on the ECV304 human umbilical vein endothelial cells and the effects of tetrandrine on the in vivo angiogenesis. Tumor size and animal survival were followed in tetrandrine-treated rats with subcutaneous or intracerebral gliomas. Expression of CD31 in tetrandrine-treated gliomas was followed to study its effect on glioma-induced angiogenesis. Tetrandrine had cytotoxic effects and induced apoptosis of glioma cells in a concentration- and time-dependent manner. Tetrandrine also inhibited the expression of VEGF in glioma cells, induced cytotoxicity effect on the ECV304 cells and suppressed the in vivo angiogenesis. Tetrandrine (150 mg/kg/day) had significant antitumor effects on subcutaneous tumors and led to slower tumor growth rate, longer animal survival time and higher animal survival (p < 0.05). Tetrandrine also affected intracerebral tumors and prolonged animal survival (p < 0.05) without affecting survival rate. Immunohistochemical analyses showed that the subcutaneous gliomas from tetrandrine-treated rats had fewer microvessel densities than control rats (p = 0.01). The results demonstrate that tetrandrine is cytotoxic to RT-2 glioma cells, has antitumor effects on subcutaneous and intracerebral gliomas, and inhibits angiogenesis in subcutaneous gliomas. Tetrandrine has potential as a treatment for gliomas.

Traditional Chinese herbal medicines for treatment of liver fibrosis and cancer: from laboratory discovery to clinical evaluation

Liver disease afflicts over 10% of the world population. This includes chronic hepatitis, alcoholic steatosis, fibrosis, cirrhosis and hepatocellular carcinoma (HCC), which are the most health-threatening conditions drawing considerable attention from medical professionals and scientists. Patients with alcoholism or viral hepatitis are much more likely to have liver cell damage and cirrhosis, and some may eventually develop HCC, which is unfortunately, and very often, a fatal malignancy without cure. While liver surgery is not suitable in many of the HCC cases, patients are mostly given palliative support cares or transarterial chemoembolization or systemic chemotherapies. However, HCC is well known to be a highly chemoresistant tumour, and the response rate is <10-20%. To this end, alternative medicines are being actively sought from other sources with hopes to halt the disease's progression or even eliminate the tumours. Traditional Chinese herbal medicine has begun to gain popularity worldwide for promoting healthcare as well as disease prevention, and been used as conventional or complementary medicines for both treatable and incurable diseases in Asia and the West. In this article, we discuss the laboratory findings and clinical trial studies of Chinese herbal medicines (particularly small molecule compounds) for the treatment of liver disease ranging from fibrosis to liver cancer.

Hemodynamic effects of synephrine treatment in portal hypertensive rats

Synephrine, a sympathomimetic alpha1-adrenoceptor agonist, has been shown to induce dose-dependent portal hypotensive effects after acute intravenous infusion. The present study was undertaken to investigate the hemodynamic effects of 8-day administration of synephrine in portal hypertensive rats. Portal hypertension was induced by either partial portal vein ligation (PVL) or bile duct ligation (BDL). Portal hypertensive rats were allocated into one of two groups: vehicle group (0.1 N HCl, 0.5 ml/12 h) or synephrine group (1 mg/kg per 12 h), with 7 rats in each group. Synephrine or vehicle was administered by gavage into PVL and BDL rats for 8 consecutive days. Systemic as well as splanchnic hemodynamic parameters were measured thereafter. Synephrine significantly ameliorated the hyperdynamic state in both PVL and BDL rats. The portal venous pressure in PVL and BDL rats (-13.5% and -10.1%, respectively), portal tributary blood flow (-19.5% and -20.4%) and cardiac index (-12.1% and -18.8%) were significantly reduced, while mean arterial pressure (10.4% and 23.4%) and systemic (26.3% and 51.0%) as well as portal territory (47.1% and 67.7%) vascular resistance were enhanced by treatment of synephrine as compared with vehicle treatment. Our results showed that eight-day administration of synephrine exerted beneficial hemodynamic effects in two models of portal hypertensive rats.

Effects of tetramethylpyrazine on portal hypertensive rats

The effects of tetramethylpyrazine, an alkaloid isolated from a Chinese herb Ligusticum wallichii Franch have been assessed in portal hypertensive rats. Portal hypertension was induced by partial portal vein ligation in Sprague-Dawley rats. Two weeks after ligation, when the hyperdynamic state had stabilized, rats were anaesthetized after an overnight fast and cannulated for measurement of mean arterial pressure, portal venous pressure, cardiac index and heart rate. Tetramethylpyrazine (3.0, 9.9 and 30mgkg(-1)) induced dose-dependent reductions of portal venous pressure and mean arterial pressure after intravenous infusion. The maximum percentage reduction of portal venous pressure after tetramethylpyrazine was 6.0+/-0.8, 9.3+/-1.6 and 20+/-2% of baseline for doses of 3.0, 9.9 and 30.0mgkg(-1), respectively. Also, total peripheral resistance was significantly reduced by tetramethylpyrazine and cardiac index was slightly increased. Our results showed that tetramethylpyrazine induced portal pressure reduction in portal hypertensive rats.