RESUMEN
OBJECTIVE: Determine the efficacy and safety of classic Chinese medicine formula Ditan Decoction (, DTD) for the treatment of Alzheimer's disease (AD) by reviewing the methods and results reported in laboratory and clinical studies in order to suggest strategies for developing more effective drugs for AD. METHODS: Embase (OVID) and China Journal Net (CJN) were searched for articles published between 1947 to November 2011 and 1915 to November 2011 respectively. Articles that fulfilled the inclusion criteria and did not meet the exclusion criteria were collected and compared in terms of research method, interventions and outcomes. RESULTS: No articles were found in Embase (OVID); 8 were found in CJN (4 laboratory studies; 4 clinical studies). The laboratory studies showed that memory impairment of AD mice models were significantly improved by DTD. The clinical studies showed that Chinese medicine which include DTD, can also relieve the memory impairment of AD patients, however, the data about the exactly effectiveness of DTD was inconclusive. CONCLUSIONS: All the clinical trials have not been fully designed yet. The evidences for recommending DTD in clinical practice were methodologically flawed. Rigid randomization in controlled clinical trials of DTD with adequate blinding and rating methods are highly recommended.
RESUMEN
Apoptosis induced by high shear stress has been reported for the dysfunction of various vascular endothelial cells. We investigated the protective effects of tetramethylpyrazine (TMP) and salvianolic acid B (SAB) from Chinese medicine on the shear-induced early and late stages of apoptosis in cultured rat cerebral microvascular endothelial cells (rCMECs) under pathological high shear stress. Near-confluent cultures of rCMECs were pretreated with TMP or SAB and their combinational dosages, and exposed to high shear stress generated by a rheometer. Apoptotic death rate of rCMECs was assessed by immunofluorescence microscopy of Annexin V-FITC and propidium iodide (PI). We found that early and late stage apoptosis occurred at 3.0 Pa for a short duration of 450 sec but did not occur at 1.5 Pa. SAB inhibited the cells from apoptosis at concentrations from 10 microM to 20 microM in a dose-dependent manner, while effect of TMP at 0.37 mM and 0.73 mM did not significantly differ. Moreover, the combined use of TMP and SAB had synergistic anti-apoptotic effects (P<0.01). The results indicate that the anti-apoptotic effect of TMP and SAB on rheologically induced endothelial injury is likely involved in their efficacy.