DMMIC derivatization-assisted liquid chromatography-mass spectrometry method for metabolite profiling of the glutathione anabolic pathway in esophageal cancer tissues and cells

In this work,a new pyrylium derivatization-assisted liquid chromatography-mass spectrometry(LC-MS)method was developed for metabolite profiling of the glutathione anabolic pathway(GAP)in cancer tissues and cells.The pyrylium salt of 6,7-dimethoxy-3-methyl isochromenylium tetrafluoroborate(DMMIC)was used to label the amino group of metabolites,and a reductant of dithiothreitol(DTT)was employed to stabilize the thiol group.By combining DMMIC derivatization with LC-MS,it was feasible to quantify the 13 main metabolites on the GAP in complex biological samples,which had good linearity(R^(2)=0.99810.9999),precision(interday precision of 1.6%e19.0%and intraday precision of 1.4%e19.8%)and accuracy(83.4%-115.7%).Moreover,the recovery assessments in tissues(82.5%e107.3%)and in cells(98.1%e118.9%)with GSH-^(13)C2,^(15)N,and Cys-^(15)N demonstrated the reliability of the method in detecting tissues and cells.Following a methodological evaluation,the method was applied successfully to investigate difference in the GAP between the carcinoma and para-carcinoma tissues of esophageal squamous cell carcinoma(ESCC)and the effect of p-hydroxycinnamaldehyde(CMSP)on the GAP in KYSE150 esophageal cancer cells.The results demonstrate that the developed method provides a promising new tool to elucidate the roles of GAP in physiological and pathological processes,which can contribute to research on drugs and diseases.

Treatment and prevention of diabetes complicated with non-alcoholic fatty liver disease by integrated traditional Chinese and Western medicine

Today’s social economy and science and technology levels are developing rapidly.Type 2 diabetes mellitus(T2DM)is increasing in incidence,and T2DM promotes non-alcoholic fatty liver disease(NAFLD)through some mechanisms.The pathogenesis of T2DM and NAFLD is interconnected,interacted with,and promoted.While increasing the economic burden on patients,it also affects the quality and life of patients themselves.In the world,the current treatment methods include exercise and diet control,drugs(including sugar reduction,lipid-lowering drugs,etc.),weight loss surgery,etc.,but currently,researching drugs can only control the progress of the disease.At present,there is no drug for T2DM combined with NAFLD treatment.Therefore,it is necessary to find and study effective drugs for NAFLD.Based on the principle of“syndrome differentiation,”traditional Chinese medicine(TCM)played an important role in treating this disease.The theory of TCM believes that the cause of NAFLD is mostly diet disorders and imbalances in daily life,leading to liver Qi stagnation,spleen dysfunction,and liver and kidney deficiency,producing phlegm and stasis.During the treatment process,we must pay attention to the goal of phlegm turbidity,but also pay attention to the source of phlegm turbidity,strengthen the spleen and stomach,nourish the liver and kidney,and restore the physiological function of the body.The ingredients of Chinese medicine extracts have the effects of antagonist oxidation stress,protecting liver cells,improving fibrous soluble systems,and promoting lipid metabolism,thereby reducing inflammatory factors to release damage to liver cells.By combining the diagnosis of TCM syndromes with Western medical disease diagnosis,the model of disease diagnosis combined with syndrome differentiation can compensate for some of the limitations of TCM’s sole reliance on syndrome differentiation,allowing for a better grasp of the disease.In treatment,a dual approach using traditional Chinese and Western medicine can enhance efficacy and reduce toxicity,leveraging both complementary strengths.Chinese medicine explains its treatment of NAFLD from a macro and micro level,providing a safer and more effective method for treating the disease.

NQO1 dependent non-canonical necroptosis mediated by ROS and RIP1/RIP3 in parallel in glioma cancer cells

OBJECTIVE Glioblastomas(GBM) are the most malignant brain tumors in humans and have a very poor prognosis.New therapeutics are urgently needed.Here,we reported 2-methoxy-6-acetyl-7-methyljuglone(MAM)-induced cell death in U87 and U251 glioma cancer cells.METHODS Cells were cultured and treated with MAM,the cell viability was determined by MTT assay and LDH assay.Intracellular reactive oxygen species(ROS) generation was observed by DCF fluorescence.The protein expression was determined by Western blotting.RESULTS MAM induced glioma cancer cell death without caspase activation.The cell death induced by MAM was attenuated by the pharmacological or genetic blockage of necroptosis signaling,including RIP1 inhibitor necrostatin-1 s(Nec-1 s) and siRNA-mediated gene silencing of RIP1 and RIP3,but was unaffected by caspase inhibitor z-vad-fmk or necrosis inhibitor 2-(1 H-Indol-3-yl)-3-pentylamino-maleimide(IM54).MAM treated U87 and U251 glioma cancer cells induced RIP1/RIP3 complex formation,ROS level increased,ATP concentration decreased and loss of plasma membrane integrity,further confirmed this process was necroptosis.The essential role of ROS was confirmed by the protective effect of ROS scavenger NAC.Interestingly,MAM induced necroptosis both triggered by RIP1/RIP3 complex and ROS generation.Moreover,MAM induced necroptosis through cytosolic calcium(Ca2 +) accumulation and sustained c-Jun N-terminal kinase(JNK) activation.Both calcium chelator BAPTA-AM and JNK inhibitor SP600125 could attenuate cell death.Further,we found there exists a feedback loop between RIP1 and JNK activation.Finally,MAM induced necroptosis was inhibited by dicoumarol(a NQO1 inhibitor).Dicoumarol exposed glioma cancer cells were resistant to RIP1/RIP3 complex formation and ROS generation.MAM induced necroptosis was independent of MLKL.CONCLUSION MAM induced non-canonical necroptosis through the NQO1-dependent ROS and RIP1/RIP3 pathway.This study also provided new insights into the molecular regulation of necroptosis in human glioma cancer cells and a promising approach for GBM treatment.

Identification of a novel autophagic inhibitor cepharanthine to enhance the anti-cancer property of dacomitinib in non-small cell lung cancer

OBJECTIVE Identification of novel autophagy inhibitors for the combinational treatment of non-small cell lung cancer(NSCLC).METHODS MTT assay and annexin V/PI staining assay were used to evaluate the cell proliferation and apoptosis,respectively.Immunofluorescence staining and cathepsin activity assay were used to detect autophagy.Small interfering RNA was performed to silence the genes and Western blot assay was used to evaluate the protein express levels.Xenograft experiments were applied for in vivo evaluation.RESULTS Cepharanthine,a natural compound,increased LC3-II expression and GFP-LC3 puncta formation in NSCLC NCI-H1975 cells.Numerous yellow puncta were observed in cepharanthine-treated cells with m RFP-EGFP-LC3 transfection.Co-staining of GFP-LC3 with LysoT racker red or LAMP1 antibody suggested that cepharanthine inhibits autophagosomes-lysosomes fusion.Moreover,cepharanthine attenuated the lysosomal cathepsins maturation.We also confirmed that dacomitinib induced cytoprotective autophagy.Combined treatment with cepharanthine increased the anti-cancer effects of dacomitinib in vitro and in vivo.Besides,cepharanthine could not enhance the anti-cancer effect of dacomitinib in autophagy deficient cells.CONCLUSION Cepharanthine might be further developed as a promising autophagic inhibitor,and combined treatment cepharanthine with dacomitinib could pose as an effective strategy for NSCLC treatment.

2-Methoxystypandrone induces iNOS expression by H_2O_2-dependent JNK activation for multiple cancer cell death

OBJECTIVE To investigate the mechanism of anticancer effect of 2-methoxystypandrone(2-MS),a natural naphthoquinone isolated from Polygonum cuspidatum Sieb.et Zucc.METHODSThree types of cancer cells were investigated in the research(A549,MCF7,B16-F10).Flow cytometer was used to determine ROS/RNS generation.Western blotting was used to detect related protein expression.Apoptosis assay,GSH/GSSG(reduced glutathione/oxidized glutathione)assay were performed using commercial kit.SiRNA knockdown was used to silence cj-un N-terminal kinase(JNK)and iNOS.High-performance liquid chromatography(HPLC)was used to detect the direct reaction of 2-MS with GSH.RESULTS 2-MS induced cytotoxity towards a panel of cancer cells,with less effect on normal cells.2-MS induced necroptosis in A549 cell and apoptosis in B16-F10 and MCF7cells.2-MS increased phosphorylation of JNK in three types of cancer cells.Inhibition of JNK with SP600125 or silencing JNK attenuated 2-MS-induced cell death.JNK also activated iNOS expression and led to nitric oxide(NO)generation in three cancer cells.NO-induced nitrative stress was responsible for DNA damage and necroptosis in A549 cells.NO also inhibited NF-κB expression and induced intrinsic apoptosis in B16-F10 and MCF7cells.Both NO scavenger hemoglobin and silencing iNOS can partially reverse 2-MS-induced cell death.Furthermore,we found that all of these were attributed to induction of hydrogen peroxide(H2O2),which was caused by glutathione(GSH)depletion through interaction of 2-MS with GSH.The interaction was validated through cell-free HPLC analysis.Both the H2O2 scavenger catalase and exogenous GSH can significantly reverse the 2-MS-induced cell death.But catalase did not protect against the decrease in GSH level.In contrast,there showed no clear increase of both H2O2 and NO in non-carcinoma liver cell LO2.CONCLUSION Taken together,a medicinal plant-derived 1,4-napthoquinone,induced iNOS expression by H2O2-dependent JNK activation,caused nitrative stress,finally led to cancer cell death by necroptosis or apoptosis.

Herbivore-induced rice resistance against rice blast mediated by salicylic acid

In agro-ecosystems,plants are important mediators of interactions between their associated herbivorous insects and microbes,and any change in plants induced by one species may lead to cascading effects on interactions with other species.Often,such effects are regulated by phytohormones such as jasmonic acid(JA)and salicylic acid(SA).Here,we investigated the tripartite interactions among rice plants,three insect herbivores(Chilo suppressalis,Cnaphalocrocis medinalis or Nilapai-vata lugens),and the causal agent of rice blast disease,the fungus Magnaporthe oryzae.We found that pre-infestation of rice by C.suppressalis or N.lugens but not by C.medinalis conferred resistance to M.oryzae.For C.suppressalis and N.lugens,insect infestation without fungal inoculation induced the accumulation of both JA and SA in rice leaves.In contrast,infestation by C.medinalis increased JA levels but reduced SA levels.The exogenous application of SA but not of JA conferred resistance against M.oryzae.These results suggest that preinfestation by C suppressalis or N.lugens conferred resistance against M.oryzae by increasing SA accumulation.These findings enhance our understanding of the interactions among rice plant,insects and pathogens,and provide valuable information for developing an ecologically sound strategy for controlling rice blast.