Neuroprotective effect of the traditional Chinese herbal formula Tongxinluo: a PET imaging study in rats

Tongxinluo has been widely used in China for the treatment of acute stroke and for neuroprotection. However, there are few positron emission tomography （PET） studies on the neuroprotective effect of Tongxinluo on cerebral ischemia/reperfusion in small animals. In the present study, Tongxinluo superfine powder suspension or its vehicle was administered intragastrically to rats for 5 successive days before middle cerebral artery occlusion, ^18Ffluorodeoxyglucose （FDG） small animal PET imaging showed that at 1 and 2 weeks after cerebral ischemia/reperfusion, glucose metabolism in the ischemic area was greater in rats that had received Tongxinluo than in those that had received the vehicle. Nissl staining showed that 2 weeks after cerebral ischemia/reperfusion, there was less neuronal loss in the prefrontal cortex in Tongxinluo-treated rats than in controls. In addition, Tongxinluo-treated animals showed better neurologic function and lower cerebral infarct volume than rats that received the vehicle. These findings suggest that Tongxinluo exhibits neuroprotective effects in cerebral ischemia/reperfusion injury and demonstrates that ^18F-FDG small animal PET imaging is a useful tool with which to study the molecular pharmacology of traditional Chinese medicine.

Intervention of Tongxinluo Capsule (通心络胶囊) against Vascular Lesion of Atherosclerosis and Its Effect on Lectin-like Oxidized Low Density Lipoprotein Receptor-1 Expression in Rabbits

Objective.- To investigate the prevention by Tongxinluo capsule （通心络胶囊, TXL） of vascular lesions and its effect on the levels of protein and gene expression of lectin-like oxidized low-density lipoprotein receptor-1 （LOX-1） of vascular wall in rabbits with atherosclerosis （AS）, and to explore its possible mechanism against AS. Methods： AS models were established by feeding New Zealand white rabbits with high-cholesterol diet, and 24 immature rabbits were randomly divided into the control group, model group and treated group （treated with TXL capsule）. The indexes of total cholesterol （TO） and low density lipoprotein （LDL） levels were measured at the 16th week. The intima thickness and the plaque area of abdominal aorta were quantitatively analyzed by pathological morphological analysis, the expression of macrophage and smooth muscle cell （SMC） in intima were detected by immunohistochemical method and histologic segments were stained by Hematoxilin-Eosin （HE） to identify the degree of atherosclerotic lesion in the model group and the prevention by TXL. The LOX-1 gene and protein expression in abdominal aorta was detected by semi-quantitative RT-PCR and immunohistochemistry, respectively. Results： In the model group, the levels of TC and LDL were significantly elevated, aortic intima thickened extensively, the intima area enhanced, and macrophages expression increased; the levels of LOX-1 gene and protein expression was up-regulated in endothelium and neo-intima of the abdominal aorta. The treatment with TXL reduced blood lipids, attenuated arterial intimal proliferation, markedly inhibited the expression of macrophage and excessively expressed the level of LOX-1. Conclusion：TXL has an inhibitory effect on blood lipids, and it can prevent the occurrence of vascular lesion and cure its development, and its protection against AS was possibly associated with a crucial endothelial protective action through lowering the expression of LOX-1 in vascular walls.

Tongxinluo Capsule(通心络胶囊)for Cardiac Syndrome X：A Systematic Review and Meta-Analysis

Objective： To evaluate the efficacy and safety of Tongxinluo Capsule（通心络胶囊, TXL） for patients with cardiac syndrome X（CSX）. Methods： Randomized controlled trials（RCTs） regarding TXL in the treatment of CSX were searched in Chinese Biomedicine Literature Database, China National Knowledge Infrastructure, Chinese Scientific Journal Database, Wanfang Database, Pub Med, EMBASE, Cochrane Central Register of Controlled Trial, websites of the Chinese and International Clinical Trial Registry platform up to June 30, 2015. The intervention was either TXL alone or TXL combined with conventional treatment, while the control intervention was conventional treatment with or without placebo. Data extraction, methodological quality assessment and data analyses were performed according to the Cochrane criteria. The primary outcome was a composite event of death, acute myocardial infarction（AMI）, angina requiring hospitalization, revascularization, and heart failure. The secondary outcome measures were angina symptom improvement, electrocardiograph（ECG） improvement, and serum endothelin-1（ET-1） level. The adverse events were also recorded. RevMan 5.3 software was applied for data analyses. Results： Twelve RCTs（696 patients） were included. Compared with conventional treatment, the addition of TXL to conventional treatment showed some benefits on relieving angina symptoms [risk ratio（RR）： 1.46, 95% confidence interval（CI）（1.25, 1.71）, P〈0.01], and improving ECG [RR： 1.45, 95% CI（1.21, 1.74）, P〈0.01]. The pooled result did not support a benefit of TXL on reducing the incidence of primary outcome [RR： 0.20, 95% CI（0.02, 1.61）, P=0.13]. In addition, TXL decreased serum ET-1 concentration of CSX patients [standardized mean number： –1.63, 95% CI（–2.29, –0.96）, P〈0.01]. No serious adverse events were reported. Conclusions： TXL documents potential benefits on attenuating angina symptoms, improving ECG and decreasing serum ET-1 level for CSX patients. However, more rigorous RCTs with high quality are needed to confirm its efficacy and safety.