Protective effects of Forsythia suspense extract with antioxidant and anti-inflammatory properties in a model of rotenone induced neurotoxicity

The present study investigated the neuroprotective effects of Forsythia suspense extract in a rotenone-induced neurotoxic model. FS8, one of the herbal extracts, markedly protected PC12 cells against rotenone toxicity and was selected for the in vivo study. Gavage administration of FS8 (50 and 200 mg/kg, but not 10 mg/kg) for 25 days significantly improved the behavior function, decreased the loss of dopaminergic neurons in substantia nigra (SN), and maintained the level of dopamine in striatum after unilateral infusion of rotenone in SN. Wherein, the protective effects of FS8 at the dose of 200 mg/kg were better than selegiline. Further study indicated the excellent antioxidant activity of FS8 on the 5th and 21st days after intranigral injection of rotenone. Moreover, FS8 could inhibit microglia activity and accumulation in SN, and obviously decreased the expression of pro-inflammatory molecules (IL-6, TNF-α, iNOS and COX-2), which indicated the anti-inflammatory effects of FS8. In the PI3K/Akt/NF-κB and MAPK pathways, FS8 significantly down-regulated the protein expression of p-PI3K, p-Akt, p-IκB, p-P65, cleaved Caspase 8, p-p38 and p-JNK but not p-mTOR, cleaved Caspase 3 and p-ERK. Therefore, FS8 protected dopamine neurons against rotenone toxicity via antioxidant and anti-inflammatory effects, which suggested the promising application of FS8 in the prevention and treatment of Parkinson disease.     

Effects of Traditional Herbal Formulae on Human CYP450 Isozymes

Objective:To assess the effects of traditional herbal formulae Sijunzi Decoction(四君子汤,Sagunja-tang,SJZD),Siwu Decoction(四物汤,Samul-tang,SWD),Bawu Decoction(八物汤,Palmul-tang,BWD)and Shiquan Dabu Decoction(十全大补汤,Sipjeondaebo-tang,SDD) on the activities of human cytochrome P450(CYP450),a drug-metabolizing enzyme.Methods:Herbal formula water extracts were filtered and lyophilized after the powder extracts were dissolved in distilled water.The activities of major human CYP450isozymes(CYP3A4,CYP2C19,CYP2D6 and CYP2E1) were measured using in vitro fluorescence-based enzyme assays.The inhibitory effects of the herbal formulas on the activities of CYP450 were characterized as half maximal inhibition concentration(IC_(50)) values.Results:All the tested herbal formulae inhibited CYP2C19activity(IC_(50):SJZD,83.28 μg/mL;SWD,235.54 μg/mL;BWD,166.82 μg/mL;SDD,178.19 μg/mL);SJZD(lC_(50) = 196.46 μ g/mL),SWD(IC_(50) = 333.42 μ g/mL) and SDD(IC_(50) = 163.42 μg/mL) inhibited CYP2E1-mediated metabolism;whereas BWD exhibited comparatively weak inhibition of CYP2E1(IC_(50) = 501.78 μg/mL).None of the four herbal formulas significantly affected CYP3A4 or CYP2D6.Conclusions:These results suggest that SJZD,SWD,BWD and SDD could potentially inhibit the metabolism of co-administered synthetic drugs whose primary route of elimination is via CYP2C19.In addition,clinically relevant pharmacokinetic interactions could occur when SJZD,SWD or SDD is co-administered with drugs metabolized by CYP2E1.Our findings provide information for the safety and effective clinical use of these four classic herbal formulas.     

Induction of mitochondria-dependent apoptosis in HepG2 human hepatocellular carcinoma cells by timosaponin A-III

Timosaponin A-III (TSA-III), a saponin isolated from the rhizome of Anemarrhena asphodeloides, exhibits potent cytotoxicity and has the potential to be developed as an anticancer agent. However, the molecular mechanism underlying the anticancer activity of TSA-III has not been fully elucidated. In this study, the apoptotic effects of TSA-III were investigated in HepG2 cells. Treatment with TSA-III significantly inhibited cell growth in a concentration- and time-dependent manner by inducing apoptosis in HepG2 cells. This induction was associated with increased fluorescence intensity of Annexin V-FITC, activation of caspases, and altered expression of inhibitor of apoptosis protein (IAP) family members. In addition, TSA-III mediated mitochondrial dysfunction with the release of HtrA2/Omi, Smac/Diablo, and cytochrome c. These findings suggest that TSA-III induces mitochondria-mediated and caspase-dependent apoptosis in HepG2 cells by altering expression of the IAP family. Thus, TSA-III could possibly be used to treat other types of cancer with similar pathologic mechanisms.