Study On The Synergism And Attenuation Effect Of Deguelin And L-carnosine Combination

Deguelin is a natural flavonoids compound that has a broad anticancer spectrum including lung cancer,breast cancer,cervical cancer,colon cancer,prostate cancer,head and neck cancer and so on.However,the applicaton of deguelin is limited by its reported neurotoxicity.So far,there are very few researches involving the neurotoxicity of deguelin,hence,further investigation into the neurotoxicity of deguelin is required in order to decrease its toxicity.L-carnosine is an endogenous dipeptide that has broad pharmacological activity.The inhibitory effect of L-carnosine against aggregation of a-SYN in addition to the antioxidant activity of L-carnosine could protect neuronal cells effectively,and it is regarded as helpful in delaying the progression of PD.In recent years,the anticancer activity of carnosine was reported,thus,the combination of L-carnosine and deguelin may excert synergistic antitumor activity as well as decrease deguelin induced neurotoxicity.The contents are as follows:(1)SH-SY5Y cells were treated with different concentrations of deguelin to investigate the proliferation inhibitory effect and apoptosis inducing effect of deguelin.Flow cytometry was applied to further determine the ROS level of treated cells in order to verify whether deguelin induced apoptosis through oxidative stress.Spectrophotometry was employed to determine the activation degree of caspase-3.(2)SH-SY5Y cells were treated with different concentrations of Lrcarnosine for to investigate the effect of L-carnosine on cell proliferation.A proper concentration of L-carnosine was applied to cotreat with deguelin in order to investigate the effect of cotreating with deguelin and L-carnosine on proliferation and apoptosis of SH-SY5Y cells.Flow cytometry was employed to examine the whole ROS level of treated cells to prove L-carnosine exhibit neuroprotective effect through its antioxidant activity.(3)Western-blot/Q-PCR method were applied to determine expression level of a-synuclein and parkin of SH-SY5Y cells after treated with L-carnosine and deguelin.(4)H1299 cell was employed as in vitro tumor model,and the anticancer effect of deguelin and L-carnosine combination against H1299 cells was analyzed by Chou-Talary method.The results are as follows:(1)Deguelin inhibited SH-SY5Y cell proliferation and induced cell apoptosis in a time-and dose-dependent manner,the mechanism may be related to the elevated ROS and activated caspase-3.(2)L-carnosine protected SH-SY5Y cells from deguelin induced growth inhibitory effect and apoptosis to some extent.After cotreated with L-carnosine,ROS level of SH-SY5Y cells decreased significantly,suggesting the protective effect of L-carnosine was probably related to the antioxidant activity of L-carnosine.(3)The neurotoxicity of deguelin had no effect on the expression of a-synuclein,and the neurotoxicity of L-carnosine was probably related to downregulating expression level of parkin.L-carnosine might have excerted neuroprotective effect through ameliorating the downregulating effect on parkin(mRNA/protein)induced by deguelin.(4)Deguelin and L-carnosine ecxcerted synergistic antiproliferation effect against H1299 cells,the synergistic antiproliferation effect was not influenced by combination ratio of deguelin and L-carnosine within the dosage investigated in the research.The conclusion is that deguelin may have induced neurotoxicity through oxidative stress-induced apoptosis of neurons,L-carnosine cotreatment excerts synergistic anticancer activity and attenuates neurotoxicity to some extent.The neuroprotective effect of L-carnosine is related to upregulating parkin expression and its antioxidant activity.