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Adjuvants for vaccines with characteristics of improving adaptive immunity particularly via leverage of antigen presenting cells (APCs) are currently lacking. In a previous work we obtained a new soluble 300 kDa homogeneous ß-glucan named GFPBW1 from the fruit bodies of Granola frondosa. GFPBW1 could activate macrophages by targeting dendritic cell associated C-type lectin 1 (Dectin-1)/Syk/NF-κB signaling to achieve antitumour effects. In this study the adjuvant effects of GFPBW1 were explored with OVA-antigen and B16-OVA tumor model. We showed that GFPBW1 (5, 50, 500 µg/mL) dose-dependently promoted activation and maturation of APCs in vitro by increasing CD80, CD86 and MHC II expression. We immunized female mice with OVA in combination with GFPBW1 (50 or 300 µg) twice with an interval of two weeks. GFPBW1 markedly and dose-dependently increased OVA-specific antibody titers of different subtypes including IgG1, IgG2a, IgG2b and IgG3, suggesting that it could serve as an adjuvant for both Th1 and Th2 type immune responses. Furthermore, GFPBW1 in combination with aluminum significantly increased the titers of OVA-specific IgG2a and IgG2b, but not those of IgG1, suggesting that GFPBW1 could be used as a co-adjuvant of aluminum to compensate for Th1 deficiency. For mice immunized with OVA plus GFPBW1, no obvious pathological injury was observed in either major organs or injection sites, and no abnormalities were noted for any of the hematological parameters. When GFPBW1 served as an adjuvant in the B16-OVA cancer vaccine models, it could accomplish entire tumor suppression with preventive vaccines, and enhance antitumour efficacy with therapeutic vaccines. Differentially expressed genes were found to be enriched in antigen processing process, specifically increased tumor infiltration of DCs, B1 cells and plasma cells in the OVA plus GFPBW1 group, in accordance with its activation and maturation function of APCs. Collectively, this study systematically describes the properties of GFPBW1 as a novel potent and safe adjuvant and highlights its great potential in vaccine development.
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CKLF (chemokine-like factor)-MARVEL transmembrane domain containing protein 6 (CMTM6) is a novel regulator to maintain the stability of PD-L1. CMTM6 can colocalize and interact with PD-L1 on the recycling endosomes and cell membrane, preventing PD-L1 from lysosome-mediated degradation and proteasome-mediated degradation thus increasing the half-life of PD-L1 on the cell membrane. The difficulties in obtaining stable full-length PD-L1 and CMTM6 proteins hinder the research on their structures, function as well as related drug development. Using lauryl maltose neopentyl glycol (LMNG) as the optimized detergent and a cell membrane mimetic strategy, we assembled a stable membrane-bound full-length CMTM6-PD-L1 complex with amphipol A8-35. When the PD-1/PD-L1-CMTM6 interactions were analyzed, we found that CMTM6 greatly enhanced the binding and delayed the dissociation of PD-1/PD-L1, thus affecting immunosuppressive signaling and anti-apoptotic signaling. We then used the CMTM6-PD-L1 complex as immunogens to generate immune repertoires in camels, and identified a functional anti-CMTM6 nanobody, called 1A5. We demonstrated that the anti-CMTM6 nanobody greatly decreased T-cell immunosuppression and promoted apoptotic susceptibility of tumor cells in vitro, and mainly relied on the cytotoxic effect of CD8+ T-cells to exert tumor growth inhibitory effects in CT26 tumor-bearing mice. In conclusion, the stable membrane-bound full-length CMTM6-PD-L1 complex has been successfully used in studying PD-1/PD-L1-CMTM6 interactions and CMTM6-targeting drug development, suggesting CMTM6 as a novel tumor immunotherapy target.
Assuntos
Antígeno B7-H1 , Proteínas com Domínio MARVEL , Neoplasias , Anticorpos de Domínio Único , Animais , Camundongos , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Neoplasias/imunologia , Neoplasias/terapia , Receptor de Morte Celular Programada 1/metabolismo , Proteínas com Domínio MARVEL/imunologia , Proteínas com Domínio MARVEL/metabolismo , Engenharia de Proteínas/métodos , Anticorpos de Domínio Único/biossínteseRESUMO
The first description of the medical use of licorice appeared in "Shennong Bencao Jing", one of the well-known Chinese herbal medicine classic books dated back to 220-280 AD. As one of the most commonly prescribed Chinese herbal medicine, licorice is known as "Guo Lao", meaning "a national treasure" in China. Modern pharmacological investigations have confirmed that licorice possesses a number of biological activities, such as antioxidation, anti-inflammatory, antiviral, immune regulation, and liver protection. 18ß-glycyrrhetinic acid is one of the most extensively studied active integrants of licorice. Here, we provide an overview of the protective effects of 18ß-glycyrrhetinic acid against various acute and chronic liver diseases observed in experimental models, and summarize its pharmacological effects and potential toxic/side effects at higher doses. We also make additional comments on the important areas that may warrant further research to support appropriate clinical applications of 18ß-glycyrrhetinic acid and avoid potential risks.
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Ácido Glicirretínico/análogos & derivados , Hepatopatias/prevenção & controle , Substâncias Protetoras/uso terapêutico , Animais , Ácido Glicirretínico/farmacologia , Ácido Glicirretínico/uso terapêutico , Ácido Glicirretínico/toxicidade , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Hepatopatias/metabolismo , Substâncias Protetoras/farmacologia , Substâncias Protetoras/toxicidadeRESUMO
Immune checkpoint inhibition is an important strategy in cancer therapy. Blockade of CTLA-4 and PD-1/PD-L1 is well developed in clinical practice. In the last few years, LAG-3 has received much interest as an emerging novel target in immunotherapy. It was recently reported that FGL1 is a major ligand of LAG-3, which is normally secreted by the liver but is upregulated in several human cancers. FGL1 is a crucial biomarker and target for cancer immunotherapy. As the efficacy of immunotherapy is limited to specific types of patients, the subset of patients needs to be selected appropriately to receive precise treatment according to different biomarkers. To date, there is no test to accurately assess FGL1 expression levels. Nanobodies have some outstanding features, such as high stability, solubility and affinity for diagnostic and therapeutic applications. Here, we report the development and validation of a rapid, sensitive, and cost-effective nanobody-based immunoassay for the detection of FGL1 in human serum. In this study, human FGL1 recombinant protein was expressed and purified for the first time as an immunized antigen. Then, we constructed a nanobody phage display library and screened several nanobodies that bind FGL1 with high affinity. We selected two nanobodies targeting different epitopes of FGL1, one as a capture and the other conjugated with HRP as a probe. The double nanobody-based sandwich ELISA to detect the concentration of FGL1 showed a good response relationship in the range of 15.625-2000 ng/mL, and the recoveries from the spiked sample were in the range of 78% and 100%. This assay could be used as a potential approach for evaluating FGL1 expression for patient stratification and for predicting the therapeutic efficacy of targeting the LAG3/FGL1 axis.
Assuntos
Fibrinogênio/imunologia , Fibrinogênio/metabolismo , Anticorpos de Domínio Único/imunologia , Anticorpos de Domínio Único/metabolismo , Animais , Camelus , Ensaio de Imunoadsorção Enzimática/métodos , Células HEK293 , Humanos , Imunoensaio/métodosRESUMO
Aristolochic acid I (AAI) is a well-known nephrotoxic carcinogen, which is currently reported to be also associated with hepatocellular carcinoma (HCC). Whether AAI is a direct hepatocarcinogen remains controversial. In this study we investigated the association between AAI exposure and HCC in adult rats using a sensitive rat liver bioassay with several cofactors. Formation of glutathione S-transferase placental form-positive (GST-P+) foci was used as the marker for preneoplastic lesions/clonal expansion. We first conducted a medium-term (8 weeks) study to investigate whether AAI had any tumor-initiating or -promoting activity. Then a long-term (52 weeks) study was conducted to determine whether AAI can directly induce HCC. We showed that oral administration of single dose of AAI (20, 50, or 100 mg/kg) in combination with partial hepatectomy (PH) to stimulate liver proliferation did not induce typical GST-P+ foci in liver. In the 8-week study, only high dose of AAI (10 mg · kg-1 · d-1, 5 days a week for 6 weeks) in combination with PH significantly increased the number and area of GST-P+ foci initiated by diethylnitrosamine (DEN) in liver. Similarly, only high dose of AAI (10 mg· kg-1· d-1, 5 days a week for 52 weeks) in combination with PH significantly increased the number and area of hepatic GST-P+ foci in the 52-week study. No any nodules or HCC were observed in liver of any AAI-treated groups. In contrast, long-term administration of AAI (0.1, 1, 10 mg· kg-1· d-1) time- and dose-dependently caused death due to the occurrence of cancers in the forestomach, intestine, and/or kidney. Besides, AAI-DNA adducts accumulated in the forestomach, kidney, and liver in a time- and dose-dependent manner. Taken together, AAI promotes clonal expansion only in the high-dose group but did not induce any nodules or HCC in liver of adult rats till their deaths caused by cancers developed in the forestomach, intestine, and/or kidney. Findings from our animal studies will pave the way for further large-scale epidemiological investigation of the associations between AA and HCC.
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Ácidos Aristolóquicos/toxicidade , Carcinógenos/toxicidade , Carcinoma Hepatocelular/etiologia , Hepatócitos/metabolismo , Neoplasias Hepáticas/etiologia , Mutagênicos/toxicidade , Animais , Carcinogênese/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Adutos de DNA/efeitos dos fármacos , Glutationa S-Transferase pi/metabolismo , Neoplasias Intestinais/induzido quimicamente , Intestinos/patologia , Rim/patologia , Neoplasias Renais/induzido quimicamente , Fígado/metabolismo , Fígado/patologia , Masculino , Ratos Sprague-Dawley , Estômago/patologia , Neoplasias Gástricas/induzido quimicamenteRESUMO
Intestinal mucositis is a common side effect of anticancer regimens that exerts a negative impact on chemotherapy. Superoxide dismutase (SOD) is a potential therapy for mucositis but efficient product is not available because the enzyme is degraded following oral administration or induces an immune reaction after intravascular infusion. Multi-modified Stable Anti-Oxidant Enzymes® (MS-AOE®) is a new recombinant SOD with better resistance to pepsin and trypsin. We referred it as MS-SOD to distinguish from other SODs. In this study we investigated its potential to alleviate 5-FU-induced intestinal injury and the mechanisms. An intestinal mucositis model was established in C57/BL6 mice by 5-day administration of 5-FU (50 mg/kg every day, ip). MS-SOD (800 IU/10 g, ig) was given once daily for 9 days. 5-FU caused severe mucositis with intestinal morphological damage, bodyweight loss and diarrhea; MS-SOD significantly decreased the severity. 5-FU markedly increased reactive oxygen species (ROS) and inflammatory cytokines in the intestine which were ameliorated by MS-SOD. Furthermore, MS-SOD modified intestinal microbes, particularly reduced Verrucomicrobia, compared with the 5-FU group. In Caco2 cells, MS-SOD (250-1000 U/mL) dose-dependently decreased tBHP-induced ROS generation. In RAW264.7 cells, MS-SOD (500 U/mL) had no effect on LPS-induced inflammatory cytokines, but inhibited iNOS expression. These results demonstrate that MS-SOD can scavenge ROS at the initial stage of injury, thus play an indirect role in anti-inflammatory and barrier protein protection. In conclusion, MS-SOD attenuates 5-FU-induced intestinal mucositis by suppressing oxidative stress and inflammation, and influencing microbes. MS-SOD may exert beneficial effect in prevention of intestinal mucositis during chemotherapy in clinic.
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Fluoruracila/efeitos adversos , Mucosa Intestinal/metabolismo , Superóxido Dismutase/metabolismo , Administração Oral , Animais , Fluoruracila/administração & dosagem , Fluoruracila/metabolismo , Injeções Intraperitoneais , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/metabolismo , Superóxido Dismutase/administração & dosagemRESUMO
Berberine, berberrubine, thalifendine, demethyleneberberine, jatrorrhizine, and columbamine are six natural protoberberine alkaloid (PA) compounds that display extensive pharmacological properties and share the same protoberberine molecular skeleton with only slight substitution differences. The oral delivery of most PAs is hindered by their poor bioavailability, which is largely caused by P-glycoprotein (P-gp)-mediated drug efflux. Meanwhile, P-gp undergoes large-scale conformational changes (from an inward-facing to an outward-facing state) when transporting substrates, and these changes might strongly affect the P-gp-binding specificity. To confirm whether these six compounds are substrates of P-gp, to investigate the differences in efflux capacity caused by their trivial structural differences and to reveal the key to increasing their binding affinity to P-gp, we conducted a series of in vivo, in vitro, and in silico assays. Here, we first confirmed that all six compounds were substrates of P-gp by comparing the drug concentrations in wild-type and P-gp-knockout mice in vivo. The efflux capacity (net efflux) ranked as berberrubine > berberine > columbamine ~ jatrorrhizine > thalifendine > demethyleneberberine based on in vitro transport studies in Caco-2 monolayers. Using molecular dynamics simulation and molecular docking techniques, we determined the transport pathways of the six compounds and their binding affinities to P-gp. The results suggested that at the early binding stage, different hydrophobic and electrostatic interactions collectively differentiate the binding affinities of the compounds to P-gp, whereas electrostatic interactions are the main determinant at the late release stage. In addition to hydrophobic interactions, hydrogen bonds play an important role in discriminating the binding affinities.
Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Berberina/análogos & derivados , Berberina/metabolismo , Animais , Berberina/sangue , Células CACO-2 , Humanos , Ligação de Hidrogênio , Fígado/química , Masculino , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Ligação ProteicaRESUMO
Cholestasis is a common feature of liver injury, which manifests as bile acid excretion and/or enterohepatic circulation disorders. However, very few effective therapies exist for cholestasis. Recently, 18ß-Glycyrrhetinic acid (18b-GA), a major metabolic component of glycyrrhizin, which is the main ingredient of licorice, was reported to protect against alpha-naphthylisothiocyanate (ANIT)-induced cholestasis. However, its protective mechanism remains unclear. We hypothesized that 18b-GA may stimulate the signaling pathway of bile acid (BA) transportation in hepatocytes, resulting its hepatoprotective effect. According to the results, 18b-GA markedly attenuated ANIT-induced liver injury as indicated the hepatic plasma chemistry index and histopathology examination. In addition, the expression levels of nuclear factors, including Sirt1, FXR and Nrf2, and their target efflux transporters in the liver, which mainly mediate bile acid homeostasis in hepatocytes, significantly increased. Furthermore, we first revealed that 18b-GA treatment significantly activated FXR, and which can be significantly reduced by EX-527 (a potent and selective Sirt1 inhibitor), indicating that 18b-GA activates FXR through Sirt1. Taken together, 18b-GA confers hepatoprotection against ANIT-induced cholestasis by activating FXR through Sirt1, which promotes gene expression of the efflux transporter, and consequently attenuates dysregulation of bile acid homeostasis in hepatocyte compartments.
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Colestase/prevenção & controle , Ácido Glicirretínico/análogos & derivados , Substâncias Protetoras/uso terapêutico , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo , 1-Naftilisotiocianato , Animais , Colestase/induzido quimicamente , Ácido Glicirretínico/uso terapêutico , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , Ratos Sprague-DawleyRESUMO
AIM: Monocrotaline (MCT) in plants of the genus Crotalaria induces significant toxicity in multiple organs including the liver, lung and kidney. Metabolic activation of MCT is required for MCT-induced toxicity. In this study, we attempted to determine whether the toxicity of MCT in kidney was a consequence of the metabolic activation of MCT in the liver. METHODS: Liver-specific cytochrome P450 reductase-null (Null) mice, wild-type (WT) mice and CYP3A inhibitor ketoconazole-pretreated WT (KET-WT) mice were examined. The mice were injected with MCT (300, 400, or 500 mg/kg, ip), and hepatotoxicity and nephrotoxicity were examined 24 h after MCT treatment. The levels of MCT and its metabolites in the blood, liver, lung, kidney and bile were determined using LC-MS analysis. RESULTS: Treatment of WT mice with MCT increased the serum levels of alanine aminotransferase, hyaluronic acid, urea nitrogen and creatinine in a dose-dependent manner. Histological examination revealed that MCT (500 mg/kg) caused severe liver injury and moderate kidney injury. In contrast, these pathological abnormalities were absent in Null and KET-WT mice. After injection of MCT (400 and 500 mg/kg), the plasma, liver, kidney and lung of WT mice had significantly lower MCT levels and much higher N-oxide metabolites contents in compared with those of Null and KET-WT mice. Furthermore, WT mice had considerably higher levels of tissue-bound pyrroles and bile GSH-conjugated MCT metabolites compared with Null and KET-WT mice. CONCLUSION: Cytochrome P450s in mouse liver play a major role in the metabolic activation of MCT and thus contribute to MCT-induced renal toxicity.
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Sistema Enzimático do Citocromo P-450/metabolismo , Rim/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Monocrotalina/farmacologia , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Animais , Rim/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos KnockoutRESUMO
AIM: Tetrandrine, an alkaloid with a remarkable pharmacological profile, induces oxidative stress and mitochondrial dysfunction in hepatocytes; however, mitochondria are not the direct target of tetrandrine, which prompts us to elucidate the role of oxidative stress in tetrandrine-induced mitochondrial dysfunction and the sources of oxidative stress. METHODS: Rat primary hepatocytes were isolated by two-step collagenase perfusion. Mitochondrial function was evaluated by analyzing ATP content, mitochondrial membrane potential (MMP) and the mitochondrial permeability transition. The oxidative stress was evaluated by examining changes in the levels of reactive oxygen species (ROS) and glutathione (GSH). RESULTS: ROS scavengers largely attenuated the cytotoxicity induced by tetrandrine in rat hepatocytes, indicating the important role of ROS in the hepatotoxicity of tetrandrine. Of the multiple ROS inhibitors that were tested, only inhibitors of CYP450 (SKF-525A and others) reduced the ROS levels and ameliorated the depletion of GSH. Mitochondrial function assays showed that the mitochondrial permeability transition (MPT) induced by tetrandrine was inhibited by SKF-525A and vitamin C (VC), both of which also rescued the depletion of ATP levels and the mitochondrial membrane potential. Upon inhibiting specific CYP450 isoforms, we observed that the inhibitors of CYP2D, CYP2C, and CYP2E1 attenuated the ATP depletion that occurred following tetrandrine exposure, whereas the inhibitors of CYP2D and CYP2E1 reduced the ROS induced by tetrandrine. Overexpression of CYP2E1 enhanced the tetrandrine-induced cytotoxicity. CONCLUSION: We demonstrated that CYP450 plays an important role in the mitochondrial dysfunction induced by the administration of tetrandrine. ROS generated by CYP450, especially CYP2E1, may contribute to the mitochondrial dysfunction induced by tetrandrine.
Assuntos
Benzilisoquinolinas/farmacologia , Citocromo P-450 CYP2E1/biossíntese , Medicamentos de Ervas Chinesas/farmacologia , Hepatócitos/metabolismo , Mitocôndrias Hepáticas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular Transformada , Células Cultivadas , Inibidores do Citocromo P-450 CYP2E1 , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/biossíntese , Inibidores Enzimáticos/farmacologia , Hepatócitos/efeitos dos fármacos , Humanos , Masculino , Mitocôndrias Hepáticas/efeitos dos fármacos , Ratos , Ratos Sprague-DawleyRESUMO
Background: Preeclampsia is a heterogeneous and complex disease with its pathogenesis mechanism not fully elucidated. A certain subset of patients with preeclampsia exhibit disturbances in lipid metabolism before clinical symptoms. Moreover, there is a tendency for preeclampsia to run in families. Whether genetic factors play a role in abnormal lipid metabolism during the incidence of preeclampsia has not been well investigated. Methods: Preeclampsia patients (n = 110) and healthy age- and gravidity-matched pregnant women (n = 110) were enrolled in this study. Peripheral blood specimens were used for genomic analysis (n = 10/group) or laboratory validation (n = 100/group). We retrospectively obtained the baseline clinical characteristics of 68 preeclampsia patients and 107 controls in early pregnancy (12-14 gestational weeks). Correlation analyses between differential genes and baseline lipid profiles were performed to identify candidate genes. In vitro and in vivo gain-of-function models were constructed with lentivirus and adeno-associated virus systems, respectively, to investigate the role of candidate genes in regulating lipid metabolism and the development of preeclampsia. Results: We observed that preeclampsia patients exhibited significantly elevated plasma TC (P = 0.037) and TG (P < 0.001) levels and increased body mass index (P = 0.006) before the disease onset. Within the region of 27 differential copy number variations, six genes potentially connected with lipid metabolism were identified. The aberrant copies of APOBEC3A, APOBEC3A_B, BTNL3, and LMF1 between preeclampsia patients and controls were verified by quantitative polymerase chain reaction. Especially, APOBEC3A showed a significant positive correlation with TC (P < 0.001) and LDL (P = 0.048) in early pregnancy. Then, our in vitro data revealed that overexpression of APOBEC3A disrupted lipid metabolism in HepG2 cells and affected both cholesterol and fatty acid metabolisms. Finally, in vivo study in a hepatic-specific overexpressed APOBEC3A mouse model revealed abnormal parameters related to lipid metabolism. Pregnant mice of the same model at the end of pregnancy showed changes related to preeclampsia-like symptoms, such as increases in sFlt-1 levels and sFlt-1/PLGF ratios in the placenta and decreases in fetal weight. Conclusion: Our findings established a new link between genetics and lipid metabolism in the pathogenesis of preeclampsia and could contribute to a better understanding of the molecular mechanisms of preeclampsia.
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Sandwich-cultured hepatocytes (SCH) are a useful tool for evaluating hepatobiliary drug transport in vitro. Some studies have investigated the in vitro-in vivo correlations of the biliary clearance of drugs using SCH. In most cases, the biliary clearance observed in vivo correlated well with the predicted clearance, but the predicted absolute values were underestimated when based on in vitro experiments with SCH. We hypothesized that the down-regulated function of uptake transporters is one of the causes of this underestimation. Therefore, the uptake of taurocholate, digoxin, pravastatin, and rosuvastatin was investigated in sandwich-cultured rat hepatocytes (SCRH) cultured for 5, 24, 48, and 96 h, and the predicted hepatic clearance from in vitro uptake clearance (CL(H, vitro)) was calculated with a dispersion model. In SCRH cultured for 96 h, the saturable uptake of taurocholate, digoxin, pravastatin, and rosuvastatin decreased to 7.5, 3.3, 64, and 23%, respectively, of their uptake in hepatocytes cultured for 5 h, and a better prediction of in vivo hepatic clearance (CL(H, vivo)) was achieved when based on CL(H, vitro) of 5-h-cultured hepatocytes. These results suggest that the uptake activity is considerably reduced in cell culture, even in a sandwich-culture format. In a similar study, we also examined taurocholate and rosuvastatin in sandwich-cultured human hepatocytes (SCHH). Unlike in SCRH, the saturable uptake of these compounds did not differ markedly in SCHH cultured for 5 or 96 h. Thus, the uptake activity in SCHH was maintained relatively well compared with that in SCRH.
Assuntos
Digoxina/farmacocinética , Fluorbenzenos/farmacocinética , Hepatócitos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Pravastatina/farmacocinética , Pirimidinas/farmacocinética , Sulfonamidas/farmacocinética , Ácido Taurocólico/farmacocinética , Animais , Bile/metabolismo , Transporte Biológico , Técnicas de Cultura de Células , Células Cultivadas , Humanos , Inativação Metabólica , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Rosuvastatina CálcicaRESUMO
Ingestion of aristolochic acid (AA), especially its major constituent aristolochic acid I (AAI), results in severe kidney injury known as aristolochic acid nephropathy (AAN). Although hepatic cytochrome P450s metabolize AAI to reduce its kidney toxicity in mice, the mechanism by which AAI is uptaken by renal cells to induce renal toxicity is largely unknown. In this study, we found that organic anion transporters (OATs) 1 and 3, proteins known to transport drugs from the blood into the tubular epithelium, are responsible for the transportation of AAI into renal tubular cells and the subsequent nephrotoxicity. AAI uptake in HEK 293 cells stably transfected with human OAT1 or OAT3 was greatly increased compared to that in the control cells, and this uptake was dependent on the AAI concentration. Administration of probenecid, a well-known OAT inhibitor, to the mice reduced AAI renal accumulation and its urinary excretion and protected mice from AAI-induced acute tubular necrosis. Further, AAI renal accumulation and severe kidney lesions induced by AAl in Oat1 and Oat3 gene knockout mice all were markedly suppressed compared to those in the wild-type mice. Together, our results suggest that OAT1 and OAT3 have a critical role in AAl renal accumulation and toxicity. These transporters may serve as a potential therapeutic target against AAN.
Assuntos
Ácidos Aristolóquicos/toxicidade , Nefropatias , Rim/efeitos dos fármacos , Rim/metabolismo , Proteína 1 Transportadora de Ânions Orgânicos/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Animais , Células HEK293 , Humanos , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Mutagênicos/toxicidade , Proteína 1 Transportadora de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos Sódio-Independentes/genética , Fatores de TempoRESUMO
Preeclampsia (PE) is a pregnancy-specific complication that seriously threatens the health and safety of mothers and infants. The etiology of PE has not been fully elucidated, and no effective treatments are currently available. A pregnant woman with PE often has to make a tough choice on either endangering her own health to give a birth or being forced to terminate her pregnancy. It is recommended by the International Federation of Gynecology and Obstetrics that the combination of maternal high-risk factors and biomarkers could form a good strategy for predicting the risk of PE. Such a combination may also enable more effective monitoring and early clinical intervention in high-risk populations to reduce the risk of PE. Therefore, biomarkers validated by extensive clinical research may be formally applied for clinical PE risk prediction. In this review, we summarized data from clinical research on potential biomarkers and classified them according to the current four major hypotheses, namely placental or trophoblast ischemia and hypoxia, vascular endothelial injury, oxidative stress, and immune dysregulation. Additionally, we also discussed the underlying mechanisms by which these potential biomarkers may be involved in the pathogenesis of PE. Finally, we propose that multiple biomarkers reflecting different aspects of the disease pathogenesis should be used in combination to detect the high-risk PE population in support of clinically targeted intervention and prevention of PE. It is expected that tests made of more sensitive and reliable PE biomarkers based on the aforementioned major hypotheses could potentially improve the accuracy of PE prediction in the future.
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Drug-induced nephrotoxicity is very common in both new drug development and clinic practice. Various drugs can induce kidney injuries, including tubulointerstitial, glomerular and renal vascular disease. To investigate the mechanism of drug induced nephrotoxicity is important for risk reduction of new drug development, reasonable drug usage, early discovery and effective prevention/treatment of adverse effects in clinics.
Assuntos
Anti-Infecciosos/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Antineoplásicos/efeitos adversos , Imunossupressores/efeitos adversos , Nefropatias/induzido quimicamente , Injúria Renal Aguda/induzido quimicamente , Animais , Humanos , Necrose Tubular Aguda/induzido quimicamente , Nefrite Intersticial/induzido quimicamente , Insuficiência Renal/induzido quimicamenteRESUMO
AIM: The role of CYP1A in the protection of aristolochic acid (AA)I-induced nephrotoxicity has been suggested. In the present study we investigated the effects of beta-naphthoflavone (BNF), a non-carcinogen CYP1A inducer, on AAI-induced kidney injury. METHODS: Mice were pretreated with 80 mg/kg BNF by daily intraperitoneal injection (ip) for 3 days followed by a single ip of 10 mg/kg AAI. AAI and its major metabolites in blood, liver and kidney, the expression of CYP1A1 and CYP1A2 in microsomes of liver and kidney, as well as the nephrotoxicity were evaluated. RESULTS: BNF pretreatment prevented AAI-induced renal damage by facilitating the disposal of AAI in liver. BNF pretreatment induced the expression of CYP1A1 in both liver and kidney; but the induction of CYP1A2 was only observed in liver. CONCLUSION: BNF prevents AAI-induced kidney toxicity primarily through CYP1A induction.
Assuntos
Ácidos Aristolóquicos/toxicidade , Nefropatias/prevenção & controle , beta-Naftoflavona/farmacologia , Doença Aguda , Animais , Ácidos Aristolóquicos/metabolismo , Citocromo P-450 CYP1A1/efeitos dos fármacos , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2/efeitos dos fármacos , Citocromo P-450 CYP1A2/metabolismo , Indução Enzimática/efeitos dos fármacos , Injeções Intraperitoneais , Rim/efeitos dos fármacos , Rim/metabolismo , Nefropatias/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismoRESUMO
The synthesis and matrix metalloproteinase (MMP) inhibitory activity of a series of gamma-keto carboxylic acids are described. Among nine MMP isozymes tested, compound 1j displays selective inhibition of MMP-2, -9, and -12 with IC(50) values between 0.20 and 1.51 microuM, and in male golden Syrian hamsters, it shows protection against PPE-induced emphysema.
Assuntos
Cetoácidos/síntese química , Inibidores de Metaloproteinases de Matriz , Enfisema Pulmonar/prevenção & controle , Animais , Cricetinae , Isoenzimas/antagonistas & inibidores , Isoenzimas/química , Cetoácidos/química , Cetoácidos/farmacologia , Masculino , Metaloproteinases da Matriz/química , Mesocricetus , Modelos Moleculares , Elastase Pancreática , Enfisema Pulmonar/induzido quimicamente , Enfisema Pulmonar/enzimologia , Relação Estrutura-Atividade , SuínosRESUMO
The current therapeutic approaches for pulmonary fibrosis, which is characterized by fibroblast proliferation and extracellular matrix remodeling, are unsatisfactory. Feitai, consisting of several herbs, is a folk formula for pulmonary tuberculosis therapy in China. To investigate the effects of Feitai on pulmonary fibrosis, Feitai was administered orally to bleomycin (BLM)-treated rats, and the lung toxicity effects were evaluated according to inflammatory cell count, protein concentration, and lactate dehydrogenase (LDH) activity in the bronchoalveolar lavage fluid (BALF), malondialdehyde level and hydroxyproline content in lung tissue 28 days post-BLM. Serial sections of the lung were stained with hematoxylin and eosin (HE) and Masson trichrome, respectively. The degree of fibrosis was assessed quantitatively using LEICA QWin image analyzer. Results showed that Feitai inhibited BLM-induced lung fibrotic lesions in a dose-dependent manner as reflected by decreased the lung hydroxyproline content and lung fibrosis fraction 28 days after BLM instillation. Treatment with Feitai also significantly ameliorated the BLM-induced lung toxicity effects detected in BALF and lung tissue. The effects in vitro on WI-38 human lung fibroblast cell line showed that Feitai significantly reduced the cell proliferation and transforming growth factor (TGF)-beta stimulated type I collagen synthesis. These results strongly demonstrate that Feitai may be useful in the treatment of pulmonary fibrosis.
Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Fibrose Pulmonar/tratamento farmacológico , Administração Oral , Animais , Bleomicina , Peso Corporal/efeitos dos fármacos , Lavagem Broncoalveolar , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo I/biossíntese , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Hidroxiprolina/metabolismo , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Pulmão/patologia , Masculino , Fibrose Pulmonar/induzido quimicamente , Ratos , Ratos Sprague-DawleyRESUMO
Baicalin (BA) exhibits anti-inflammatory effect in vivo and in vitro and is used to treat inflammatory diseases. Here, we report that BA inhibits the activation of macrophage and protects mice from macrophage-mediated endotoxin shock. The experiments in vitro showed BA suppressed the increased generation of nitric oxide (NO) and expression of inducible nitric oxide synthase (iNOS) induced by LPS or Interferon-gamma (IFN-gamma) without directly affecting iNOS activity in RAW264.7 cells and peritoneal macrophages. Similarly, BA inhibited the production of reactive oxidative species (ROS), whereas augmented the level of intracellular superoxide dismutase (SOD). Moreover, BA inhibited the production of inflammatory mediators including tumor necrosis factor (TNF)-alpha, endothelin (ET)-1 and thromboxane A2 (TXA2) induced by lipopolysaccharide (LPS) in RAW264.7 cells. In animal model, BA protected mice from endotoxin shock induced by d-galactosamine (D-GalN)/LPS possibly through inhibiting the production of cytokine and NO. Collectively, BA inhibited the production of inflammatory mediators by macrophage and may be a potential target for treatment of macrophage-mediated diseases.
Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Flavonoides/farmacologia , Lipopolissacarídeos , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , Choque Séptico/prevenção & controle , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Linhagem Celular , Modelos Animais de Doenças , Flavonoides/uso terapêutico , Macrófagos Peritoneais/enzimologia , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Choque Séptico/induzido quimicamente , Choque Séptico/enzimologia , Choque Séptico/metabolismoRESUMO
BACKGROUND: Baicalin (BA) exhibits an anti-inflammatory effect in vivo and in vitro and is used to treat chronic hepatitis. However, the mechanism by which BA exerts the liver-protective effect remains largely unknown. AIMS: The present study reports that BA inhibits cytokine production and hepatocyte apoptosis to protect mice from liver injury induced by concanavalin A (Con A), a T-cell-dependent liver injury model. RESULTS: Con A injection of mice induced severe immune responses and extensive hepatocellular apoptosis within 24 h. Pretreatment of 200 or 100 mg/kg BA markedly reduced serum aminotransferase activities, protected hepatoycte apoptosis and reduced the increase of plasma cytokine levels, including tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma) and interleukin-6 (IL-6). Furthermore, BA pretreatment decreased tissue myeloperoxidase activity and lipid peroxidation, but increased the superoxide dismutase level. In vitro studies indicated that the beneficial effect of BA was associated with reduced cytokine production from lymphocytes and reduced TNF-alpha-induced hepatocyte apoptosis. CONCLUSION: These results suggest that BA has therapeutic potential for T-cell-mediated liver injury.