Isoquercitrin attenuates the progression of non-alcoholic steatohepatitis in mice by modulating galectin-3-mediated insulin resistance and lipid metabolism.

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a global health problem with no effective treatment. Isoquercitrin (IQ) alters hepatic lipid metabolism and inhibits adipocyte differentiation. The underlying regulatory mechanisms of IQ in regulating insulin resistance (IR) and lipid metabolism remain unclear. PURPOSE: This study was aimed at investigating the effects of IQ on NASH and deciphering whether the underlying mechanisms are via modulation of galectin-3 mediated IR and lipid metabolism. METHODS: IR-HepG2 cell lines were used to demonstrate the ability of IQ to modulate galectin-3-mediated glucose disposal and lipid metabolism. A 20-week high-fat diet (HFD)-induced NASH model was established in C57BL/6J mice, and the protective effect of IQ on lipid disposal in the liver was verified. Further, the mRNA and protein levels of glucose and lipid metabolism were investigated, and lysophosphatidylcholine (LPC) and acylcarnitine (AC) profiling were performed to characterize the changes in endogenous substances associated with mitochondrial function and lipid metabolism in serum and cells. Furthermore, the pharmacokinetic features of IQ were explored in a rat model of NASH. RESULTS: IQ restored liver function and ameliorated inflammation and lipid accumulationin NASH model mice. Notably, significant regulation of the proteins included fatty acid-generating and transporting, cholesterol metabolism enzymes, nuclear transcription factors, mitochondrial metabolism, and IR-related enzymes was noted to be responsible for the therapeutic mechanisms of IQ against experimental NASH. Serum lipid metabolism-related metabolomic assay confirmed that LPC and AC biosynthesis mostly accounted for the therapeutic effect of IQ in mice with NASH and that IQ maintained the homeostasis of LPC and AC levels. CONCLUSION: This is the first study showing that IQ protects against of NASH by modulating galectin-3-mediated IR and lipid metabolism. The mechanisms responsible for liver protection and improved lipid metabolic disorder by IQ may be related to the suppression of IR and regulation of mitochondrial function and lipid metabolism. Galectin-3 down-regulation represents a potentially novel approach for the treatment and prevention of NASH.

Evaluation of characteristic metabolites of aromatic amino acids in patients with HIV infection at different stages of disease.

BACKGROUND: Acquired immune deficiency syndrome (AIDS), human immunodeficiency virus (HIV) infection, and antiretroviral therapy are usually associated with metabolic disorders. Screening for biomarkers to evaluate the progression of metabolic disorders is important for the diagnosis and treatment of HIV infection. This study aimed to establish and validate a method to quantify serum aromatic amino acid (AAA) metabolites as biomarkers of metabolic disorders in patients with HIV. METHODS: The AAAs and metabolites were analyzed using high-performance liquid chromatography-tandem mass spectrometry. Pearson's correlation, heatmap, and receiver operating characteristic curve analyses were used for statistical analysis. RESULTS: Under optimal detection conditions, the lower limits of phenylalanine (Phe), tryptophan (Trp), kynurenine (Kyn), tyrosine, phenylacetylglutamine (PAGln), and 5-hydroxytryptamine quantification reached 0.02, 0.02, 0.01, 0.02, 0.01, and 0.002 µg/ml, respectively, and the precision of intra- and inter-day was stay below 10.30%. Serum samples were stable for at least 6 months when stored at -80°C. The inter-group differences and associations between the biomarkers exhibited a particular volatility trend in PAGln, Trp, and Kyn metabolism in HIV-infected patients with metabolic syndrome. CONCLUSIONS: The developed method can be used for rapid and sensitive quantification of the AAA metabolism profile in vivo to further appraise the process of HIV infection, evaluate intervening measures, conduct mechanistic investigations, and further study the utility of PAGln, a characteristic metabolite of AAA, as a biomarker of HIV infection coupled with metabolic syndrome.

The combination of Lonicerae Japonicae Flos and Forsythiae Fructus herb-pair alleviated inflammation in liver fibrosis.

Objective: To explore the active components and epigenetic regulation mechanism underlying the anti-inflammatory effects of Lonicerae Japonicae Flos and Forsythiae Fructus herb-pair (LFP) in carbon tetrachloride (CCl4)-induced rat liver fibrosis. Methods: The main active ingredients and disease-related gene targets of LFP were determined using TCMSP and UniProt, and liver fibrosis disease targets were screened in the GeneCards database. A network was constructed with Cytoscape 3.8.0 and the STRING database, and potential protein functions were analyzed using bioinformatics analysis. Based on these analyses, we determined the main active ingredients of LFP and evaluated their effects in a CCl4-induced rat liver fibrosis model. Serum biochemical indices were measured using commercial kits, hepatocyte tissue damage and collagen deposition were evaluated by histopathological studies, and myofibroblast activation and inflammation were detected by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. High-performance liquid chromatography-mass spectrometry was performed to determine the levels of homocysteine, reduced glutathione, and oxidized glutathione, which are involved in inflammation and oxidative stress. Results: The main active components of LFP were quercetin, kaempferol, and luteolin, and its main targets were α-smooth muscle actin, cyclooxygenase-2, formyl-peptide receptor-2, prostaglandin-endoperoxide synthase 1, nuclear receptor coactivator-2, interleukinß, tumor necrosis factor α, CXC motif chemokine ligand 14, and transforming growth factor ß1. A combination of quercetin, kaempferol, and luteolin alleviated the symptoms of liver fibrosis. Conclusion: The results of this study support the role of LFP in the treatment of liver fibrosis, and reveal that LFP reduces collagen formation, inflammation, and oxidative stress. This study suggests a potential mechanism of action of LFP in the treatment of liver fibrosis.

Evaluation of lipid metabolism imbalance in HIV-infected patients with metabolic disorders using high-performance liquid chromatography-tandem mass spectrometry.

Human immunodeficiency virus (HIV) infection and highly active antiretroviral therapy use are associated with the disruption of lipid and glucose metabolism. Herein, a sensitive and robust high-performance liquid chromatography-tandem mass spectrometry method for the quantitation of lysophosphatidylcholines (LPCs) and acylcarnitines (ACs) in human blood serum was developed and validated to investigate them as markers of metabolic disorders in HIV-infected patients. Under optimal extraction and detection conditions, the lower limits of quantification reached 5 ng/mL (LPCs) and 0.1 ng/mL (ACs), and precision and accuracy for both intra- and inter-day analyses were generally below 15%. Serum samples were stable for at least six months when stored at - 80 °C and for at least 12 h when stored at 4 °C or 25 °C. We investigated inter-group differences and associations between the biomarkers and observed a particular volatilitytrend of LPCs and ACs for HIV-infected patients with metabolic disorders. Thus, the developed method can be used for the rapid and sensitive quantitation of LPCs and ACs in vivo to further appraise the process of HIV infection, evaluate interveningmeasures, conduct mechanistic investigations, and further study the utility of LPCs and ACs as biomarkers of HIV infection coupled with metabolic disorders.

Quercetin 7-rhamnoside protects against alpha-naphthylisothiocyanate (ANIT)-induced in cholestatic hepatitis rats by improving biliary excretion and inhibiting inflammatory responses.

Objective: To explore the pharmacological effects and molecular mechanism of quercetin 7-rhamnoside (Q7R) in the treatment of cholestatic hepatitis induced by alpha-naphthylisothiocyanate (ANIT). Methods: ANIT-induced cholestatic hepatitis rat model was used to investigate the hepatoprotective effects of three different doses of Q7R (1.25 mg/kg; 2.5 mg/kg; 5 mg/kg). Serum biochemical indices were detected using commercial kits. H&E and masson staining were used to observe hepatic tissue damage and collagen deposition in hepatocytes. The metabolism of bile acid-related substances was detected via HPLC-MS/MS by 5-(diisopropylamino) amylamine (DIAAA) derivative method. Hepatocyte injury, cholestasis, and inflammation were detected at the mRNA and protein levels using reverse transcription-polymerase chain reaction (RT-PCR) and western blotting, respectively. Results: Q7R can decrease the level of CYP7A1, and increase FXR, CYP27A1 so then improving abnormal bile acid secretion. Furthermore, Q7R can also ameliorating inflammation by reduce TNF-α, IL-1ß, PTGS1, PTGS2, NCOA2, NF-κB level. Therefore, Q7R had an effective therapeutic effect on ANIT-induced cholestatic hepatitis, improving abnormal bile acid secretion, and inhibiting inflammatory responses. Conclusion: The results demonstrated that Q7R treat cholestatic hepatitis by regulating bile acid secretion and alleviating inflammation.

Delivery of Rapamycin by Liposomes Synergistically Enhances the Chemotherapy Effect of 5-Fluorouracil on Colorectal Cancer.

BACKGROUND: Rapamycin is a promising agent for treating tumors, but clinical applications of rapamycin are limited due to its poor water solubility and low bioavailability. This paper constructs a liposome delivery system for rapamycin to improve the effect in treating colorectal cancer. METHODS: We prepared the rapamycin liposomes using the ethanol injection method. The cellular uptake and biodistribution were detected by LC-MS and in vivo imaging system. MTT assay, transwell migration experiment, flow cytometry, and Western blot analysis evaluated the antitumor effect of rapamycin liposomes in vitro. Furthermore, HCT-116 tumor-bearing mice were used to assess the therapeutic efficacy of rapamycin liposomes in vivo. RESULTS: The prepared rapamycin liposomes had a particle size of 100±5.5 nm and with a narrow size distribution. In vitro cellular uptake experiments showed that the uptake of rapamycin liposomes by colorectal cells was higher than that of free rapamycin. Subsequently, in vivo imaging experiments also demonstrated that rapamycin liposomes exhibited higher tumor accumulation. Therefore, the ability of rapamycin liposomes to inhibit tumor proliferation, migration and to induce tumor apoptosis is superior to that of free rapamycin. We also demonstrated in vivo good antitumor efficacy of the rapamycin liposomes in HCT-116 xenograft mice. In addition, rapamycin liposomes and 5-FU can synergistically improve the efficacy of colorectal cancer via the Akt/mTOR and P53 pathways. CONCLUSION: Collectively, rapamycin liposomes are a potential treatment for colorectal cancer, as it not only improves rapamycin's antitumor effect but also synergistically enhances 5-FU's chemotherapy effect.

T-cell death-associated gene 8 accelerates atherosclerosis by promoting vascular smooth muscle cell proliferation and migration.

BACKGROUND AND AIMS: Atherosclerosis is a serious cardiovascular disease, featuring inflammation, abnormal proliferation and migration of vascular smooth muscle cells (VSMCs). During atherosclerosis, inflammation may cause low pH. T-cell death-associated gene 8 (Tdag8) is a proton-sensing receptor, however, the role of Tdag8 in VSMCs remains unknown. This study aimed to investigate the potential effects of Tdag8 in VSMCs during atherosclerosis. METHODS: We examined the expression of Tdag8 in an atherosclerotic model of high-fat-diet-fed ApoE-/- mice, while the role and mechanism of Tdag8 in phenotype transformation, proliferation and migration of VSMCs were investigated in a series of in vivo and in vitro experiments. RESULTS: We first found that Tdag8 expression at the mRNA and protein level was significantly increased in atherosclerotic ApoE-/- mice. Immunofluorescence staining showed that Tdag8 was primarily distributed in PCNA-positive VSMCs and the phenotype of VSMCs switching from contractile phenotype to synthetic phenotype. Additionally, the protein level of Tdag8 was upregulated in FBS-treated VSMCs. VSMCs proliferation and migration were inhibited by Tdag8 silencing and increased by Tdag8 overexpression. Further mechanistic studies showed that cAMP level was increased in Tdag8-overexpressing VSMCs and ApoE-/- mice. However, the PKA inhibitor H-89 reversed Tdag8-induced VSMC proliferation and migration. CONCLUSIONS: The results demonstrate that Tdag8 mediated phenotype transformation, proliferation and migration of VSMCs via the cAMP/PKA signaling pathway, thus partially contributing to atherosclerosis.

Combinational applicaton of silybin and tangeretin attenuates the progression of non-alcoholic steatohepatitis (NASH) in mice via modulating lipid metabolism.

Silybin (SB) is widely used to treat chronic liver diseases, especially this compound is much efficient for the treatments of alcoholic and non-alcoholic steatohepatitis (NASH). However, low bioavailability seriously limits wide-application of SB in biomedical niche. Prior to this study, we found that tangeretin (TG) could remarkably increase the bioavailability of SB by the inhibition of efflux transporters, which encourges us to therapeutical discovery of SB and TG combitional use against NASH. Here, we revealed that TG is capable of improving hepatic-protective activity of SB in mice with NASH by interfering liver oxidative stress, inflammation, and lipid accumulation. In addition, TG was observed to enhance the exposural level of SB in the plasma and liver of mice. Our metabolome assay confirmed that amino acid metabolism and lipid biosynthesis mostly accounted for combitional use of SB and TG to teat NASH in mice, basically biosynthesis of unsaturated fatty acids was mostly affected. Notably, significant inhibitions in fatty acid generating and transporting proteins such as G6PD, FABP4, LPL and CD36/FAT, and cholesterol metabolism enzyme CYP27A1 as well as nuclear transcription factors FXR, PPAR-γ, and LXR were illustrated to decipher therapeutic mechanisms of SB and TG against experimental NASH. Taken together, the strategy based combitional use of SB and TG has a potential-capacity to treat NASH.

Identification of a new inhibitor of KRAS-PDEδ interaction targeting KRAS mutant nonsmall cell lung cancer.

Oncogenic KRAS is considered a promising target for anti-cancer therapy. However, direct pharmacological strategies targeting KRAS-driven cancers remained unavailable. The prenyl-binding protein PDEδ, a transporter of KRAS, has been identified as a potential target for pharmacological inhibitor by selectively binding to its prenyl-binding pocket, impairing oncogenic KRAS signaling pathway. Here, we discovered a novel PDEδ inhibitor (E)-N'-((3-(tert-butyl)-2-hydroxy-6,7,8,9-tetrahydrodibenzo[b,dfuran-1-yl)methylene)-2,4-dihydroxybenzohydrazide(NHTD) by using a high-throughput docking-based virtual screening approach. In vitro and in vivo studies demonstrated that NHTD suppressed proliferation, induced apoptosis and inhibited oncogenic K-RAS signaling pathways by disrupting KRAS-PDEδ interaction in nonsmall cell lung cancer (NSCLC) harboring KRAS mutations. NHTD redistributed the localization of KRAS to endomembranes by targeting the prenyl-binding pocket of PDEδ and exhibited the suppression of abnormal KRAS function. Importantly, NHTD prevented tumor growth in xenograft and KRAS mutant mouse model, which presents an effective strategy targeting KRAS-driven cancer.

Baicalein Enhances the Oral Bioavailability and Hepatoprotective Effects of Silybin Through the Inhibition of Efflux Transporters BCRP and MRP2.

Although hepatoprotective properties of silybin are well documented, the clinical therapeutic efficacy is limited by its low bioavailability due to absorption rates, extensive phase II metabolism, and biliary excretion. As our previous study indicated that metabolic enzymes may have limited effects on the pharmacokinetic (PK) behavior of silymarin, here, we intended to increase the oral bioavailability and bio-efficacy of silybin through the inhibition of active efflux. In Caco-2 and transfected MDCKII cell models, flavone baicalein significantly inhibited the efflux of silybin as a BCRP and MRP2 inhibitor. In addition, baicalein reduced the biliary excretion index (BEI) and biliary clearance of silybin conjugates in the sandwich-cultured rat hepatocyte (SCH) model, indicating the inhibition of baicalein in biliary excretion of conjugated silybin metabolites. PK study demonstrated that baicalein significantly increased the area under the curve (AUC) and Cmax of silybin and its conjugates, suggesting enhanced absorption in vivo. Moreover, coadministration of silybin with baicalein boosted the liver protective, antioxidant, and anti-inflammatory effects of silybin in the carbon tetrachloride (CCl4)-induced liver injury model in comparison with silybin given alone. In summary, efflux transporters play a critical role in the low bioavailability of silybin, while inhibition of breast cancer resistance protein (BCRP) and multi-drug resistance protein 2 (MRP2) by baicalein can significantly increase the absorption and bio-efficacy of silybin, which provides a new combination therapeutic approach for the treatment of chronic liver diseases.

Palmatine ameliorated murine colitis by suppressing tryptophan metabolism and regulating gut microbiota.

Inflammatory bowel disease (IBD), majorly include Crohn's disease (CD) and ulcerative colitis (UC), is chronic and relapsing inflammatory disorders of the gastrointestinal tract, which treatment options remain limited. Here we examined the therapeutic effects of an isoquinoline alkaloid, Palmatine (Pal), on mice experimental colitis induced by dextran sulfate sodium (DSS) and explored underlying mechanisms. Colitis was induced in BALB/c mice by administering 3% DSS in drinking water for 7 days. Pal (50 and 100 mg kg-1) and the positive drug Sulfasalazine (SASP, 200 mg kg-1) were orally administered for 7 days. Disease activity index (DAI) was evaluated on day 8, and colonic tissues were collected for biochemistry analysis. The fecal microbiota was characterized by high-throughput Illumina MiSeq sequencing. And plasma metabolic changes were detected by UPLC-MS. Our results showed that Pal treatment significantly reduced DAI scores and ameliorated colonic injury in mice with DSS-induced colitis. Mucosal integrity was improved and cell apoptosis was inhibited. Moreover, gut microbiota analysis showed that mice received Pal-treatment have higher relative abundance of Bacteroidetes and Firmicutes, but reduced amount of Proteobacteria. Moreover, Pal not only suppressed tryptophan catabolism in plasma, but also decreased the protein expression of indoleamine 2,3-dioxygenase 1 (IDO-1, the rate-limiting enzyme of tryptophan catabolism) in colon tissue. This is consolidated by molecular docking, which suggested that Pal is a potent IDO-1 inhibitor. Taken together, our findings demonstrate that Pal ameliorated DSS-induced colitis by mitigating colonic injury, preventing gut microbiota dysbiosis, and regulating tryptophan catabolism, which indicated that Pal has great therapeutic potential for colitis.

Role of tangeretin as a potential bioavailability enhancer for silybin: Pharmacokinetic and pharmacological studies.

Biological responses of a variety of naturally occurring compounds in vivo were restrained by their poor oral bioavailability. Silybin, as one of the active ingredients of silymarin, has presented promising bioactivity for the treatment of chronic liver diseases and cancer. However, its exposure in body was limited. In this study, silybin was demonstrated to be substrates of both BCRP and MRP2 by utilizing monolayer Caco-2 cell model and confirmed in MDCK cells overexpressing specific efflux transporter. Of all compounds screened, tangeretin, a potent inhibitor of efflux transporters of BCRP, MRP2 and P-gp, was able to enhance exposure of silybin by inhibiting functions of the barriers mediating transcellular transport. Moreover, study carried out in sandwich-cultured rat hepatocyte (SCH) model showed that the biliary excretion index (BEI) and in vitro biliary clearance of silybin decreased as levels of tangeretin increased, indicating efflux transporters mediating biliary excretion of silybin might be involved. Pharmacokinetic behaviors of silybin in rats were altered by co-administration of tangeretin, in terms of increased AUC and Cmax of silybin by comparing with that of silybin given alone. In addition, results coming from CCl4-induced acute liver injury rat model revealed that protection effect of silybin against liver damage in the presence of tangeretin was significantly enhanced. All these data were evident that efflux transporters play a critical role in transcellular transport of silybin and account for its low bioavailability. Enhanced bioavailability of silybin with co-administration of tangeretin by significantly inhibiting the efflux transporters further boost its bioactivity which is of particular importance in clinical use.

Suppression of Lipogenesis via Reactive Oxygen Species-AMPK Signaling for Treating Malignant and Proliferative Diseases.

AIMS: Systemic diseases often have common characteristics. The aim of this study was to investigate the feasibility of targeting common pathological metabolism to inhibit the progression of malignant and proliferative diseases. RESULTS: Gefitinib-resistant (G-R) nonsmall-cell lung cancer (NSCLC) and rheumatoid arthritis (RA) were studied as conditions representative of malignant and proliferative diseases, respectively. Strong lipogenic activity and high expression of sterol regulatory element-binding protein 1 (SREBP1) were found in both G-R NSCLC cells and synovial fibroblasts from RA patients (RASFs). Berberine (BBR), an effective suppressor of SREBP1 and lipogenesis regulated through reactive oxygen species (ROS)/AMPK pathway, selectively inhibited the growth of G-R NSCLC cells and RASFs but not that of normal cells. It effectively caused mitochondrial dysfunction, activated ROS/AMPK pathway, and finally suppressed cellular lipogenesis and cell proliferation. Addition of ROS blocker, AMPK inhibitor, and palmitic acid significantly reduced the effect of BBR. In an in vivo study, treatment of BBR led to significant inhibition of mouse tumor xenograft growth and remarkably slowed down the development of adjuvant-induced arthritis in rats. Innovation and Conclusion: Targeting ROS/AMPK/lipogenesis signaling pathway selectively inhibited the growth of G-R NSCLC cells and the progress of RASFs in vitro and in vivo, which provides a new avenue for treating malignancies and proliferative diseases. Antioxid. Redox Signal. 28, 339-357.

Patchouli alcohol ameliorates dextran sodium sulfate-induced experimental colitis and suppresses tryptophan catabolism.

Despite the increased morbidity of ulcerative colitis (UC) in recent years, available treatments remain unsatisfactory. Pogostemon cablin has been widely applied to treat a variety of gastrointestinal disorders in clinic for centuries, in which patchouli alcohol (PA, C15H26O) has been identified as the major active component. This study attempted to determine the bioactivity of PA on dextran sulfate sodium (DSS)-induced mice colitis and clarify the mechanism of action. Acute colitis was induced in mice by 3% DSS for 7 days. The mice were then given PA (10, 20 and 40mg/kg) or sulfasalazine (SASP, 200mg/kg) as positive control via oral administration for 7 days. At the end of study, animals were sacrificed and samples were collected for pathological and other analysis. In addition, a metabolite profiling and a targeted metabolite analysis, based on the Ultra-Performance Liquid Chromatography coupled with mass spectrometry (UPLC-MS) approach, were performed to characterize the metabolic changes in plasma. The results revealed that PA significantly reduced the disease activity index (DAI) and ameliorated the colonic injury of DSS mice. The levels of colonic MPO and cytokines involving TNF-α, IFN-γ, IL-1ß, IL-6, IL-4 and IL-10 also declined. Furthermore, PA improved the intestinal epithelial barrier by enhancing the level of colonic expression of the tight junction (TJ) proteins, for instance ZO-1, ZO-2, claudin-1 and occludin, and by elevating the levels of mucin-1 and mucin-2 mRNA. The study also demonstrated that PA inhibited the DSS-induced cell death signaling by modulating the apoptosis related Bax and Bcl-2 proteins and down-regulating the necroptosis related RIP3 and MLKL proteins. By comparison, up-regulation of IDO-1 and TPH-1 protein expression in DSS group was suppressed by PA, which was in line with the declined levels of kynurenine (Kyn) and 5-hydroxytryptophan (5-HTP) in plasma. The therapeutic effect of PA was evidently reduced when Kyn was given to mice. In summary, the study successfully demonstrated that PA ameliorated DSS-induced mice acute colitis by suppressing inflammation, maintaining the integrity of intestinal epithelial barrier, inhibiting cell death signaling, and suppressing tryptophan catabolism. The results provided valuable information and guidance for using PA in treatment of UC.

Tangeretin, a citrus pentamethoxyflavone, antagonizes ABCB1-mediated multidrug resistance by inhibiting its transport function.

Multidrug resistance (MDR) and tumor metastasis are the main causes of chemotherapeutic treatment failure and mortality in cancer patients. In this study, at achievable nontoxic plasma concentrations, citrus flavonoid tangeretin has been shown to reverse ABCB1-mediated cancer resistance to a variety of chemotherapeutic agents effectively. Co-treatment of cells with tangeretin and paclitaxel activated apoptosis as well as arrested cell cycle at G2/M-phase. Tangeretin profoundly inhibited the ABCB1 transporter activity since it significantly increased the intracellular accumulation of doxorubicin, and flutax-2 in A2780/T cells and decreased the efflux of ABCB1 substrates in Caco2 cells without altering the expression of ABCB1. Moreover, it stimulated the ATPase activity and inhibited verapamil-stimulated ATPase activity in a concentration-dependent manner, indicating a direct interaction with the transporter. The molecular docking results indicated a favorable binding of tangeretin with the transmemberane region site 1 of homology modeled ABCB1 transporter. The overall results demonstrated that tangeretin could sensitize ABCB1-overexpressing cancer cells to chemotherapeutical agents by directly inhibiting ABCB1 transporter function, which encouraged further animal and clinical studies in the treatment of resistant cancers.

Quantitative evaluation of berberine subcellular distribution and cellular accumulation in non-small cell lung cancer cells by UPLC-MS/MS.

Berberine, an isoquinoline alkaloid, has been demonstrated to be a safe anti-cancer agent with multiple effects on mitochondria. Intracellular concentration and distribution around the targeting sites are determinants of efficacy, but subcellular distribution of berberine has not been fully elucidated yet, which relies on the sensitive and robustness assay. In this study, a sensitive and robust UPLC-MS/MS method has been developed and validated with optimized extraction solvents and detection conditions. Key factors such as the purity and integrity of isolated organelle fractions, and the effects of isolation procedures on the subcellular concentration of berberine were systemically evaluated. With the developed assay, we found that the intracellular accumulations of berberine in two gefitinib resistant NSCLC cell lines H1650 and H1975 were 2-3 folds higher than that of normal epithelial cells BEAS-2B. Moreover, significantly different subcellular distribution profiles in NSCLC cancer cells from that of BEAS-2B cells with a striking increase in content in most organelles may contribute to its selective cytotoxicity to cancer cells. Furthermore, a predominant accumulation of berberine was observed for the first time in microsomal fraction for all three cell lines. Therefore, this method could be used for quantitative evaluation of subcellular distribution and cellular accumulation of berberine and for further evaluation of the concentration-effects relationship.