Effects and Mechanism of Combination of Rhein and Danshensu in the Treatment of Chronic Kidney Disease.

Traditional Chinese medicine (TCM) plays a systemic role in disease treatment, targeting multiple etiological factors simultaneously. Based on clinical experience, rhubarb and Salvia miltiorrhiza are commonly prescribed together for the treatment of chronic kidney disease (CKD) and have been proven to be very effective. However, the rationale of the combination remains unclear. The major active ingredients of these two herbs are rhein (RH) and danshensu (DSS), respectively. The aim of this paper is to investigate the renoprotective effects of RH and DSS in vitro and in vivo, and the underlying mechanism. A total of 5/6 nephrectomy rats and HK-2 cells were subjected to chronic renal injury. The combination of RH and DSS conferred a protective effect, as shown by a significant improvement in the renal function, blood supply, and fibrotic degree. Proinflammatory cytokines and adhesion molecules were suppressed by RH and DSS through NK-κB signaling. The combination also inhibited apoptosis by up-regulating Bcl-2 and down-regulating Bax. Inhibiting the TGF-ß/Smad3 pathway was at least in part involved in the antifibrotic mechanism of the combination treatment of RH and DSS. This study demonstrates for the first time the renoprotective effect and the mechanism of RH and DSS combination on chronic renal injury. It could provide experimental evidence to support the rationality of the combinatorial use of TCM in clinical practices.

Insulinotropic effect of Chikusetsu saponin IVa in diabetic rats and pancreatic ß-cells.

ETHNOPHARMACOLOGICAL RELEVANCE: As a well-known traditional Chinese medicine the root bark of Aralia taibaiensis has traditionally been used as the medicine considered alleviating several disorders including diabetes mellitus (DM). Chikusetsu saponin IVa (CHS) has been defined as a major active ingredient of triterpenoid saponins extracted from Aralia taibaiensis. The scientific evidence of anti-diabetic effect for CHS remains unknown and the purpose of our study was to study its hypoglycemic and insulin secretagogue activities. MATERIALS AND METHODS: In vivo studies were performed on type 2 diabetic mellitus (T2DM) rats given CHS for 28 days to test the antihyperglycemic activity. The in vitro effects and possible mechanisms of CHS on the insulin secretion in pancreatic ß-cell line ßTC3 were determined. RESULTS: Oral administration of CHS dose-dependently increased the level of serum insulin and decreased the rise in blood glucose level in an in vivo treatment. In vitro, CHS potently stimulated the release of insulin from ßTC3 cells at both basal and stimulatory glucose concentrations, the effect which was changed by the removal of extracellular Ca(2+). Two methods showed that CHS enhanced the intracellular calcium levels in ßTC3 cells. CHS was capable of enhancing the phosphorylation of extracellular signal-regulated protein kinases C (PKC), which could be reversed by a PKC inhibitor (RO320432), and the insulin secretion induced by CHS was also inhibited by RO320432. Further study also showed that the insulinotropic effect, intracellular calcium levels and the phosphorylation of PKC were reduced by inhibiting G protein-coupled receptor 40 (GPR40) by a GPR40 inhibitor (DC126026). CONCLUSION: These observations suggest that the signaling of CHS-induced insulin secretion from ßTC3 cells via GPR40 mediated calcium and PKC pathways and thus CHS might be developed into a new potential for therapeutic agent used in T2DM patients.

Antihyperglycemic, hypolipidemic and antioxidant activities of total saponins extracted from Aralia taibaiensis in experimental type 2 diabetic rats.

ETHNOPHARMACOLOGICAL RELEVANCE: As a well-known traditional Chinese medicine the root bark of Aralia taibaiensis has multiple pharmacological activities, including relieving rheumatism, promoting blood circulation to arrest pain, inducing diuresis to reduce edema, and antidiabetic action. It has long been used as a folk medicine for the treatment of traumatic injury, rheumatic arthralgia, nephritis, edema, hepatitis and diabetes mellitus in China. AIM OF STUDY: To evaluate the antihyperglycemic, hypolipidemic and antioxidant activities of total saponins extracted from Aralia taibaiensis (SAT) in experimental type 2 diabetic mellitus (T2DM) rats. MATERIALS AND METHODS: Acute toxicity was studied in rats to determine the safe oral dose of SAT. Then, SAT was given orally to normal and streptozotocin-nicotinamide induced T2DM rats at 80, 160 and 320 mg/kg doses for a series of 28 days to determine the antihyperglycemic activity. Glibenclamide (600 µg/kg), a standard antidiabetic drug, was used as a positive control drug. At the end of treatment, biochemical parameters and antioxidant levels were measured to evaluate the hypolipidemic and antioxidant activities of SAT. RESULTS: Oral administration of SAT did not exhibit toxicity and death at a dose not more than 2000 mg/kg. SAT dose-dependently improved the symptoms of polydipsia, polyuria, polyphagia and weight loss in diabetic rats. Compared with diabetic control group, administration of 320 mg/kg SAT resulted in significant (P<0.05) fall in the levels of fasting blood glucose, glycosylated hemoglobin, creatinine, urea, alanine transarninase, aspartate aminotransferase, total cholesterol, triglycerides, low density lipoprotein cholesterol and malondialdehyde, but significant (P<0.05) increase in the levels of serum insulin, superoxide dismutase and reduced glutathione. However, SAT did not have any effect on the normal rats. CONCLUSIONS: SAT had excellent antihyperglycemic, hypolipidemic and antioxidant activities in T2DM rats and might be a promising drug in the therapy of diabetes mellitus and its complications.

Dissection of mechanisms of a chinese medicinal formula: danhong injection therapy for myocardial ischemia/reperfusion injury in vivo and in vitro.

Traditional Chinese medicine uses a systemic treatment approach, targeting multiple etiological factors simultaneously. Danhong injection (DHI), a very popular Chinese medicine injection, is reported to be effective for many cardiovascular conditions. The primary active ingredients of DHI, and their systemic and interrelated mechanism have not been evaluated in an established myocardial ischemia/reperfusion (MI/R) model. We identified the main active constituents in DHI, including hydroxysafflor yellow A (A), salvianolic acid B (B), and danshensu (C), by HPLC fingerprint analysis and assessed their effect on MI/R rats and cardiomyocytes. These 3 compounds and DHI all decreased the levels of IL-1, TNF- α , and MDA, increased those of IL-10 and SOD activity in vivo and in vitro, and had antiapoptotic effects, as shown by flow cytometric analysis and TUNEL assay. Moreover, these compounds increased phosphorylation of Akt and ERK1/2 in cardiomyocytes. Interestingly, we found compound A exerted a more prominent anti-inflammatory effect than B and C, by decreasing NF- κ B levels; compound B had more powerful antioxidative capacity than A and C, by increasing Nrf2 expression; compound C had stronger antiapoptotic ability than A and B, by lowering caspase-3 activity. Our results elucidate the mechanisms by which DHI protects against MI/R induced injury.

Safflor yellow A protects neonatal rat cardiomyocytes against anoxia/reoxygenation injury in vitro.

AIM: To investigate the effects of safflor yellow A (SYA), a flavonoid extracted from Carthamus tinctorius L, on cultured rat cardiomyocytes exposed to anoxia/reoxygenation (A/R). METHODS: Primary cultured neonatal rat cardiomyocytes were exposed to anoxia for 3 h followed by reoxygenation for 6 h. The cell viability was measured using MTT assay. The releases of lactate dehydrogenase (LDH) and creatine kinase (CK), level of malondialdehyde (MDA), and activities of glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were analyzed. Hoechst 33258 staining and changes in Bcl-2/Bax ratio and caspase 3 activity were used to examine A/R-induced apoptosis. RESULTS: The A/R exposure markedly decreased the viability of cardiomyocytes, suppressed the activities of SOD, GSH, CAT and GSH-Px, and Bcl-2 protein expression. Meanwhile, the A/R exposure markedly increased the release of LDH and CK, and MDA production in the cardiomyocytes, and increased the rate of apoptosis, caspase 3 activity, Bax protein expression. Pretreatment with SYA (40, 60 and 80 nmol/L) concentration-dependently blocked the A/R-induced changes in the cardiomyocytes. Pretreatment of the cardiomyocytes with the antioxidant N-acetylcysteine (NAC, 200 µmol/L) produced protective effects that were comparable to those caused by SYA (80 nmol/L). CONCLUSION: SYA protects cultured rat cardiomyocytes against A/R injury, maybe via inhibiting cellular oxidative stress and apoptosis.

Insulin-secretagogue activity of eleven plant extracts and twelve pure compounds isolated from Aralia taibaiensis.

AIMS: To investigate the insulinogenic activities of the eleven saponins enriched traditional Chinese medicine (TCM) extracts. MAIN METHODS: Radioimmunoassay and trypan blue exclusion assay were used to investigate the insulinogenic activity and cytotoxic effects respectively. KEY FINDINGS: The total saponin extract of Aralia taibaiensis (sAT) exhibited highest insulinogenic activity and no cytotoxicity was recorded. Twelve pure compounds from sAT stimulated insulin secretion from a mouse insulinoma ßTC3 cells in a concentration-dependent manner. TA35 outperformed the other compounds which suggested that the active insulinogenic ingredient of sAT was probably TA35. In addition, both sAT and TA35 markedly potentiated glucose-induced insulin secretion. SIGNIFICANCE: Our study is the first to show that sAT dramatically stimulated insulin secretion and its antidiabetic activity may be related to its high saponin content. These findings suggested that sAT and the compound TA35 isolated from sAT may provide novel therapeutic tools for the treatment of non-insulin dependent diabetes mellitus (NIDDM).