Studies have indicated that flavonoid luteolin is a potential inhibitor of tumor cell proliferation and may function as an anticarcinogenic agent. Pyrrolidine dithiocarbamate (PDTC), a synthetic compound, may exhibit ...Studies have indicated that flavonoid luteolin is a potential inhibitor of tumor cell proliferation and may function as an anticarcinogenic agent. Pyrrolidine dithiocarbamate (PDTC), a synthetic compound, may exhibit biphasic effects on apoptosis depending on the experimental context. Previously, we found that luteolin induced the activation of the proapoptotic proteins, such as Bad, Bid, and Bax, in HL-60 human leukemia cells. We also explored the modulatory effects and molecular mechanisms of PDTC on the cytotoxicity of luteolin in HL-60 cells;PDTC could interfere with luteolin’s ability to cleave poly(ADP-ribose)-polymerase (PARP) and DNA fragmentation of factor-45 (DFF-45). In the current study, we further investigated the effect of PDTC on the luteolin-induced death-receptor pathway and the cleavage of the Bcl-2 family members. We found that the combination of luteolin and PDTC increased the survival of the HL-60 cells such that PDTC inhibited both extrinsic and intrinsic pathways in luteolin-induced apoptosis.展开更多
Objective:To study the effect of pyrrolidine dithiocarbamate(PDTC) on the anti-tuberculosis drug-induced liver injury and the molecular mechanism. Methods:Clean male SD rats were selected as experimental animals and r...Objective:To study the effect of pyrrolidine dithiocarbamate(PDTC) on the anti-tuberculosis drug-induced liver injury and the molecular mechanism. Methods:Clean male SD rats were selected as experimental animals and randomly divided into normal group,model group,PDTC group and AG490 group. Animal model of anti-tuberculosis drug-induced liver injury was established by intragastric administration isoniazid + rifampicin. PDTC group received intraperitoneal injection of PDTC,and AG490 group received intraperitoneal injection of AG490. Twenty-eight days after intervention,the rats were executed,and the liver injury indexes,inflammation indexes and oxidative stress indexes in serum as well as JAK2/STAT3 expression,liver injury indexes,inflammation indexes and oxidative stress indexes in liver tissue were determined. Results:p-JAK2,p-STAT3,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA expression in liver tissue as well as TBIL,ALT,AST,γ-GT,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA levels in serum of model group were significantly higher than those of normal group while p-JAK2,p-STAT3,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA expression in liver tissu as well as TBIL,ALT,AST,γ-GT,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA levels in serum of PDTC group and AG490 group were significantly lower than those of model group. Conclusions:PDTC can inhibit the inflammation and oxidative stress mediated by JAK2/STAT3 signaling pathway to alleviate the anti-tuberculosis drug-induced liver injury.展开更多
BACKGROUND: The nuclear translocation of transcription factors may be a critical factor in the intracellular pathway involved in ischemia/reperfusion(I/R) injury. The aim of the study was to evaluate the role of nucle...BACKGROUND: The nuclear translocation of transcription factors may be a critical factor in the intracellular pathway involved in ischemia/reperfusion(I/R) injury. The aim of the study was to evaluate the role of nuclear factor-kappa B (NF-κB) in the pathogenesis of liver injury induced by intestinal ischemia/reperfusion (IIR) and to investigate the effect of pyrrolidine dithiocarbamate (PDTC) on this liver injury. METHODS: Male Wistar rats were divided randomly into three experimental groups (8 rats in each): sham operation group (control group); intestinal/reperfusion group(I/R group): animals received 1-hour of intestinal ischemia and 2-hour reperfusion; and PDTC treatment group (PDTC group): animals that received I/R subject to PDTC treatment (100 mg/kg). The histological changes in the liver and intestine were observed, and the serum levels of tumor necrosis factor-α (TNF-α), alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver superoxide dismutase (SOD), and nitrite/nitrate (NO) were measured. The immunohistochemical expression and Western blot analysis of liver NF-κB and intercellular adhesion molecule-1(ICAM-1) were observed. RESULTS: IIR induced liver injury characterized by the histological changes of liver edema, hemorrhage, polymorphonuclear neutrophil (PMN) infiltration, and elevated serum levels of AST and ALT. The serum TNF-α level was significantly higher than that of the control group(P<0.01) and a high level of liver oxidant product was observed (P<0.01). These changes were parallel to the positive expression of NF-κB and ICAM-1. After the administration of PDTC, the histological changes after liver injury were improved; the levels of SOD and NO in the liver were elevated and reduced, respectively (P<0.01). The expressions of ICAM-1 and NF-κB in the liver were weakened (P<0.01). CONCLUSION: NF-κB plays an important role in the pathogenesis of liver injury induced by HR. PDTC, an agent known to inhibit the activation of NF-κB, can reduce and prevent this injury.展开更多
AIM: To explore the changes of nuclear factor-kappa B (NF-κB) DNA-binding activity, the expression of intercellular adhesion molecule-1 (ICAM-1) regulated by NF-κB at various times and to evaluate the effects of pyr...AIM: To explore the changes of nuclear factor-kappa B (NF-κB) DNA-binding activity, the expression of intercellular adhesion molecule-1 (ICAM-1) regulated by NF-κB at various times and to evaluate the effects of pyrrolidine dithiocarbamate (PDTC) on trinitrobenzene sulfonic acid (TNBS)-induced rat colitis.METHODS: TNBS of 0.6 mL was mixed with ethanol of 0.3 mL solution and instilled into the lumen of the rat colon. The rat models were divided into 6 groups, which were killed at 24 h, 3, 7, 14, and 21 d after enema. Colonic inflammation and damage were assessed by macroscopical and histological criteria. Activity of NF-κB DNA-binding was analyzed by electrophoresis mobility shift assays (EMSA).Expression of ICAM-1 was detected by in situ hybridization (ISH) and immunohistochemistry (IH). Then various doses of PDTC were injected into rat abdomen 30 min before enema with TNBS/ethanol as pretreatment. The rats were killed 4 h after enema and the colonic inflammation,myeloperoxidase (MPO) activity, malondialdehyde (MDA)level, and DNA-binding activity of NF-κB were assessed.Finally, PDTC was injected intraperitoneally after colitis was induced. Changes of morphology were assayed.RESULTS: During the first week, hyperemia, hemorrhage,edema and ulceration of the colonic mucosa appeared with predominant infiltration of leukocytes. Neutrophils,macrophages, lymphocytes infiltrated in mucosa and submucosa 14 d later. Fibroblasts and granuloma-like structures were also obviously seen. The binding activity of NF-κB began to increase at 24 h time point and reached a peak at 14 d, then decreased but still was higher than control group at 21 d (P＜0.01). Levels of tCAM-1 mRNA and protein significantly elevated at 24 h and the peak was at 21 d. Pretreatment with PDTC could attenuate the development of inflammation but not by reducing NF-κB activity. This attenuation of inflammation had a positive relationship with the dose of PDTC. PDTC at the dose of 100 mg/kg had no therapeutic effect after colitis was induced.CONCLUSION: NF-κB activation is an important event that may be involved in acute and chronic inflammation development and may contribute to self-protection against early inflammation damage. NF-κB also regulates ICAM-1expression during colonic inflammation. Pretreatment of PDTC may attenuate the inflammation development. But PDTC has no therapeutic effect after the colitis is induced.展开更多
AIM: To evaluate the effect of pyrrolidine dithio- carbamate (PDTC; an NF-κB inhibitor) administered at low (50 mg/kg) and high (100 mg/kg) doses in suppressing colitis in mice with dextran sodium sulfate (DSS)-induc...AIM: To evaluate the effect of pyrrolidine dithio- carbamate (PDTC; an NF-κB inhibitor) administered at low (50 mg/kg) and high (100 mg/kg) doses in suppressing colitis in mice with dextran sodium sulfate (DSS)-induced colitis. METHODS: Mice were divided into a DSS-untreated group (normal group), DSS-treated control group, DSS+PDTC-treated groupⅠ(low-dose group), and DSS+PDTC-treated groupⅡ (high-dose group). In each group, the disease activity index score (DAI score), intestinal length, histological score, and the levels of activated NF-κB and inflammatory cytokines (IL-1β and TNF-α) in tissue were measured. RESULTS: The DSS+PDTC-treated groupⅡ exhibited suppression of shortening of intestinal length and reduction of DAI score. Activated NF-κB level and IL-1β and TNF-α levels were significantly lower in DSS+PDTC- treated groupⅡ. CONCLUSION: These findings suggest that PDTC is useful for the treatment of ulcerative colitis.展开更多
Objective: To evaluate the antioxidant, immunomodulatory and anti-inflammatory activities of pyrrolidine dithiocarbamate and saxagliptin in rats with thioacetamide-induced ulcerative colitis. Methods: Animals were ora...Objective: To evaluate the antioxidant, immunomodulatory and anti-inflammatory activities of pyrrolidine dithiocarbamate and saxagliptin in rats with thioacetamide-induced ulcerative colitis. Methods: Animals were orally administered with a vehicle, sulfasalazine(500 mg/kg), pyrrolidine dithiocarbamate(100 mg/kg), and saxagliptin(10 mg/kg) for two weeks. Ulcerative colitis was induced by a single intrarectal instillation of thioacetamide on day 8. Colon samples were collected to assess mitogen-activated protein kinase(MAPK), phosphorylated extracellular signal-regulated kinase(ERK), c AMP response element-binding protein(CREB), interleukin-12(IL-12), caspase-3, β-defensin, inducible nitric oxide synthase(i NOS) and glucagon like peptide-1(GLP-1). Moreover, histopathological examination was performed. Results: Rats treated with thioacetamide caused increases in colonic MAPK, phosphorylated ERK, CREB, caspase-3, IL-12, β-defensin, i NOS, as well as decreases in body weight and GLP-1. In addition, distortion of colonic structure was found by histopathological examination. Pyrrolidine dithiocarbamate and saxagliptin mitigated colitis severity by improving body weight decrease and GLP-1, and reducing colonic MAPK, phosphorylated ERK, CREB, caspase-3, IL-12, β-defensin and i NOS. Conclusions: Pyrrolidine dithiocarbamate and saxagliptin are efficient against thioacetamide induced colitis through improving inflammatory and oxidative changes.展开更多
目的研究高糖毒性对INS-1细胞胰岛素基因及其转录因子PDX-1和Maf A表达的影响,及NF-κB抑制剂吡咯烷二硫基甲酸盐(PDTC)的保护作用,探讨"糖毒性"的生化机制。方法分别以4.0 mmol/L葡萄糖(NG组)、16.7mmol/L葡萄糖(HG组)及16.7...目的研究高糖毒性对INS-1细胞胰岛素基因及其转录因子PDX-1和Maf A表达的影响,及NF-κB抑制剂吡咯烷二硫基甲酸盐(PDTC)的保护作用,探讨"糖毒性"的生化机制。方法分别以4.0 mmol/L葡萄糖(NG组)、16.7mmol/L葡萄糖(HG组)及16.7 mmol/L葡萄糖+50μmol/L PDTC(HG+P组)培养INS-1细胞,48 h后,离心收集细胞,提取总RNA,以real-ti me PCR法检测胰岛素基因及转录因子PDX-1和Maf A的mRNA水平。结果HG组与NG组比较,胰岛素mRNA的表达下降了64.9%(P<0.05);PDX-1 mRNA的表达下降了82.3%(P<0.01);Maf A mRNA的表达下降了80.9%(P<0.01)。HG+P组与HG组相比,胰岛素mRNA的表达则提高了6.67倍(P<0.05);PDX-1mRNA的表达提高了7.52倍(P<0.05);Maf A mRNA的表达提高了5.70倍(P<0.01);而与NG组相比,胰岛素、PDX-1和Maf A mRNA的表达差异均无统计学意义(均P>0.05)。结论"糖毒性"可以通过激活INS-1细胞内的NF-κB途径,使胰岛素转录因子PDX-1和Maf A的表达下降,而导致胰岛素基因表达下降,抑制NF-κB可起到保护作用。展开更多
文摘Studies have indicated that flavonoid luteolin is a potential inhibitor of tumor cell proliferation and may function as an anticarcinogenic agent. Pyrrolidine dithiocarbamate (PDTC), a synthetic compound, may exhibit biphasic effects on apoptosis depending on the experimental context. Previously, we found that luteolin induced the activation of the proapoptotic proteins, such as Bad, Bid, and Bax, in HL-60 human leukemia cells. We also explored the modulatory effects and molecular mechanisms of PDTC on the cytotoxicity of luteolin in HL-60 cells;PDTC could interfere with luteolin’s ability to cleave poly(ADP-ribose)-polymerase (PARP) and DNA fragmentation of factor-45 (DFF-45). In the current study, we further investigated the effect of PDTC on the luteolin-induced death-receptor pathway and the cleavage of the Bcl-2 family members. We found that the combination of luteolin and PDTC increased the survival of the HL-60 cells such that PDTC inhibited both extrinsic and intrinsic pathways in luteolin-induced apoptosis.
基金supported by Surface Project of Shandong Provincial Natural Science Foundation(No.ZR2014HM081)
文摘Objective:To study the effect of pyrrolidine dithiocarbamate(PDTC) on the anti-tuberculosis drug-induced liver injury and the molecular mechanism. Methods:Clean male SD rats were selected as experimental animals and randomly divided into normal group,model group,PDTC group and AG490 group. Animal model of anti-tuberculosis drug-induced liver injury was established by intragastric administration isoniazid + rifampicin. PDTC group received intraperitoneal injection of PDTC,and AG490 group received intraperitoneal injection of AG490. Twenty-eight days after intervention,the rats were executed,and the liver injury indexes,inflammation indexes and oxidative stress indexes in serum as well as JAK2/STAT3 expression,liver injury indexes,inflammation indexes and oxidative stress indexes in liver tissue were determined. Results:p-JAK2,p-STAT3,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA expression in liver tissue as well as TBIL,ALT,AST,γ-GT,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA levels in serum of model group were significantly higher than those of normal group while p-JAK2,p-STAT3,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA expression in liver tissu as well as TBIL,ALT,AST,γ-GT,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA levels in serum of PDTC group and AG490 group were significantly lower than those of model group. Conclusions:PDTC can inhibit the inflammation and oxidative stress mediated by JAK2/STAT3 signaling pathway to alleviate the anti-tuberculosis drug-induced liver injury.
文摘BACKGROUND: The nuclear translocation of transcription factors may be a critical factor in the intracellular pathway involved in ischemia/reperfusion(I/R) injury. The aim of the study was to evaluate the role of nuclear factor-kappa B (NF-κB) in the pathogenesis of liver injury induced by intestinal ischemia/reperfusion (IIR) and to investigate the effect of pyrrolidine dithiocarbamate (PDTC) on this liver injury. METHODS: Male Wistar rats were divided randomly into three experimental groups (8 rats in each): sham operation group (control group); intestinal/reperfusion group(I/R group): animals received 1-hour of intestinal ischemia and 2-hour reperfusion; and PDTC treatment group (PDTC group): animals that received I/R subject to PDTC treatment (100 mg/kg). The histological changes in the liver and intestine were observed, and the serum levels of tumor necrosis factor-α (TNF-α), alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver superoxide dismutase (SOD), and nitrite/nitrate (NO) were measured. The immunohistochemical expression and Western blot analysis of liver NF-κB and intercellular adhesion molecule-1(ICAM-1) were observed. RESULTS: IIR induced liver injury characterized by the histological changes of liver edema, hemorrhage, polymorphonuclear neutrophil (PMN) infiltration, and elevated serum levels of AST and ALT. The serum TNF-α level was significantly higher than that of the control group(P<0.01) and a high level of liver oxidant product was observed (P<0.01). These changes were parallel to the positive expression of NF-κB and ICAM-1. After the administration of PDTC, the histological changes after liver injury were improved; the levels of SOD and NO in the liver were elevated and reduced, respectively (P<0.01). The expressions of ICAM-1 and NF-κB in the liver were weakened (P<0.01). CONCLUSION: NF-κB plays an important role in the pathogenesis of liver injury induced by HR. PDTC, an agent known to inhibit the activation of NF-κB, can reduce and prevent this injury.
基金Supported by a Grant From Health Department Foundation of Guangdong Province, No. A2003554
文摘AIM: To explore the changes of nuclear factor-kappa B (NF-κB) DNA-binding activity, the expression of intercellular adhesion molecule-1 (ICAM-1) regulated by NF-κB at various times and to evaluate the effects of pyrrolidine dithiocarbamate (PDTC) on trinitrobenzene sulfonic acid (TNBS)-induced rat colitis.METHODS: TNBS of 0.6 mL was mixed with ethanol of 0.3 mL solution and instilled into the lumen of the rat colon. The rat models were divided into 6 groups, which were killed at 24 h, 3, 7, 14, and 21 d after enema. Colonic inflammation and damage were assessed by macroscopical and histological criteria. Activity of NF-κB DNA-binding was analyzed by electrophoresis mobility shift assays (EMSA).Expression of ICAM-1 was detected by in situ hybridization (ISH) and immunohistochemistry (IH). Then various doses of PDTC were injected into rat abdomen 30 min before enema with TNBS/ethanol as pretreatment. The rats were killed 4 h after enema and the colonic inflammation,myeloperoxidase (MPO) activity, malondialdehyde (MDA)level, and DNA-binding activity of NF-κB were assessed.Finally, PDTC was injected intraperitoneally after colitis was induced. Changes of morphology were assayed.RESULTS: During the first week, hyperemia, hemorrhage,edema and ulceration of the colonic mucosa appeared with predominant infiltration of leukocytes. Neutrophils,macrophages, lymphocytes infiltrated in mucosa and submucosa 14 d later. Fibroblasts and granuloma-like structures were also obviously seen. The binding activity of NF-κB began to increase at 24 h time point and reached a peak at 14 d, then decreased but still was higher than control group at 21 d (P＜0.01). Levels of tCAM-1 mRNA and protein significantly elevated at 24 h and the peak was at 21 d. Pretreatment with PDTC could attenuate the development of inflammation but not by reducing NF-κB activity. This attenuation of inflammation had a positive relationship with the dose of PDTC. PDTC at the dose of 100 mg/kg had no therapeutic effect after colitis was induced.CONCLUSION: NF-κB activation is an important event that may be involved in acute and chronic inflammation development and may contribute to self-protection against early inflammation damage. NF-κB also regulates ICAM-1expression during colonic inflammation. Pretreatment of PDTC may attenuate the inflammation development. But PDTC has no therapeutic effect after the colitis is induced.
文摘AIM: To evaluate the effect of pyrrolidine dithio- carbamate (PDTC; an NF-κB inhibitor) administered at low (50 mg/kg) and high (100 mg/kg) doses in suppressing colitis in mice with dextran sodium sulfate (DSS)-induced colitis. METHODS: Mice were divided into a DSS-untreated group (normal group), DSS-treated control group, DSS+PDTC-treated groupⅠ(low-dose group), and DSS+PDTC-treated groupⅡ (high-dose group). In each group, the disease activity index score (DAI score), intestinal length, histological score, and the levels of activated NF-κB and inflammatory cytokines (IL-1β and TNF-α) in tissue were measured. RESULTS: The DSS+PDTC-treated groupⅡ exhibited suppression of shortening of intestinal length and reduction of DAI score. Activated NF-κB level and IL-1β and TNF-α levels were significantly lower in DSS+PDTC- treated groupⅡ. CONCLUSION: These findings suggest that PDTC is useful for the treatment of ulcerative colitis.
文摘Objective: To evaluate the antioxidant, immunomodulatory and anti-inflammatory activities of pyrrolidine dithiocarbamate and saxagliptin in rats with thioacetamide-induced ulcerative colitis. Methods: Animals were orally administered with a vehicle, sulfasalazine(500 mg/kg), pyrrolidine dithiocarbamate(100 mg/kg), and saxagliptin(10 mg/kg) for two weeks. Ulcerative colitis was induced by a single intrarectal instillation of thioacetamide on day 8. Colon samples were collected to assess mitogen-activated protein kinase(MAPK), phosphorylated extracellular signal-regulated kinase(ERK), c AMP response element-binding protein(CREB), interleukin-12(IL-12), caspase-3, β-defensin, inducible nitric oxide synthase(i NOS) and glucagon like peptide-1(GLP-1). Moreover, histopathological examination was performed. Results: Rats treated with thioacetamide caused increases in colonic MAPK, phosphorylated ERK, CREB, caspase-3, IL-12, β-defensin, i NOS, as well as decreases in body weight and GLP-1. In addition, distortion of colonic structure was found by histopathological examination. Pyrrolidine dithiocarbamate and saxagliptin mitigated colitis severity by improving body weight decrease and GLP-1, and reducing colonic MAPK, phosphorylated ERK, CREB, caspase-3, IL-12, β-defensin and i NOS. Conclusions: Pyrrolidine dithiocarbamate and saxagliptin are efficient against thioacetamide induced colitis through improving inflammatory and oxidative changes.
文摘目的研究高糖毒性对INS-1细胞胰岛素基因及其转录因子PDX-1和Maf A表达的影响,及NF-κB抑制剂吡咯烷二硫基甲酸盐(PDTC)的保护作用,探讨"糖毒性"的生化机制。方法分别以4.0 mmol/L葡萄糖(NG组)、16.7mmol/L葡萄糖(HG组)及16.7 mmol/L葡萄糖+50μmol/L PDTC(HG+P组)培养INS-1细胞,48 h后,离心收集细胞,提取总RNA,以real-ti me PCR法检测胰岛素基因及转录因子PDX-1和Maf A的mRNA水平。结果HG组与NG组比较,胰岛素mRNA的表达下降了64.9%(P<0.05);PDX-1 mRNA的表达下降了82.3%(P<0.01);Maf A mRNA的表达下降了80.9%(P<0.01)。HG+P组与HG组相比,胰岛素mRNA的表达则提高了6.67倍(P<0.05);PDX-1mRNA的表达提高了7.52倍(P<0.05);Maf A mRNA的表达提高了5.70倍(P<0.01);而与NG组相比,胰岛素、PDX-1和Maf A mRNA的表达差异均无统计学意义(均P>0.05)。结论"糖毒性"可以通过激活INS-1细胞内的NF-κB途径,使胰岛素转录因子PDX-1和Maf A的表达下降,而导致胰岛素基因表达下降,抑制NF-κB可起到保护作用。
