BACKGROUND Study shows that signal transducer and activator of transcription 3(STAT3) can increase the Warburg effect by stimulating hexokinase 2 in breast cancer and upregulate lactate dehydrogenase A and pyruvate de...BACKGROUND Study shows that signal transducer and activator of transcription 3(STAT3) can increase the Warburg effect by stimulating hexokinase 2 in breast cancer and upregulate lactate dehydrogenase A and pyruvate dehydrogenase kinase 1 in myeloma. STAT3 and pyruvate kinase M2(PKM2) can also be activated and enhance the Warburg effect in hepatocellular carcinoma. Precancerous lesions are critical to human and rodent hepatocarcinogenesis. However, the underlying molecular mechanism for the development of liver precancerous lesions remains unknown. We hypothesized that STAT3 promotes the Warburg effect possibly by upregulating p-PKM2 in liver precancerous lesions in rats.AIM To investigate the mechanism of the Warburg effect in liver precancerous lesions in rats.METHODS A model of liver precancerous lesions was established by a modified Solt-Farber method. The liver pathological changes were observed by HE staining and immunohistochemistry. The transformation of WB-F344 cells induced with Nmethyl-N'-nitro-N-nitrosoguanidine and hydrogen peroxide was evaluated by the soft agar assay and aneuploidy. The levels of glucose and lactate in the tissue and culture medium were detected with a spectrophotometer. The protein levels of glutathione S-transferase-π, proliferating cell nuclear antigen(PCNA), STAT3,and PKM2 were examined by Western blot and immunofluorescence.RESULTS We found that the Warburg effect was increased in liver precancerous lesions in rats. PKM2 and p-STAT3 were upregulated in activated oval cells in liverprecancerous lesions in rats. The Warburg effect, p-PKM2, and p-STAT3 expression were also increased in transformed WB-F344 cells. STAT3 activation promoted the clonal formation rate, aneuploidy, alpha-fetoprotein expression,PCNA expression, G1/S phase transition, the Warburg effect, PKM2 phosphorylation, and nuclear translocation in transformed WB-F344 cells.Moreover, the Warburg effect was inhibited by stattic, a specific inhibitor of STAT3, and further reduced in transformed WB-F344 cells after the intervention for PKM2.CONCLUSION The Warburg effect is initiated in liver precancerous lesions in rats. STAT3 activation promotes the Warburg effect by enhancing the phosphorylation of PKM2 in transformed WB-F344 cells.展开更多
The Janus kinase and signal transducer and activator of transcription （JAK/STAT） signal transduction pathway is involved in sepsis-induced functional damage to the heart, liver, kidney, and other organs. However, th...The Janus kinase and signal transducer and activator of transcription （JAK/STAT） signal transduction pathway is involved in sepsis-induced functional damage to the heart, liver, kidney, and other organs. However, the cellular and molecular mechanisms underlying sepsis-induced brain damage remain elusive. In the present study, we found severe loss of neurons in the hippocampal CA1 region in rats with sepsis-induced brain damage following intraperitoneal injection of endotoxin, The expression of toll-like receptor 4, tumor necrosis factor a, and interleukin-6 was significantly increased in brain tissues following lipopolysaccharide exposure. AG490 （JAK2 antagonist） and rapamycin （STAT3 antagonist） significantly reduced neuronal loss and suppressed the increased expression of toll-like receptor 4, tumor necrosis factor a, and interleukin-6 in the hippocampal CA1 region in sepsis-induced brain damaged rats. Overall, these data suggest that blockade of the JAK/STAT signal transduction pathway is neuroprotective in sepsis-induced brain damage via the inhibition of toll-like receptor 4, tumor necrosis factor a, and interleukin-6 exoression.展开更多
Hepatocellular carcinoma is one of the most common cancers worldwide,and a leading cause of cancer-related death.Owing to unsatisfactory clinical outcomes under the current standard of care,there is a need to search f...Hepatocellular carcinoma is one of the most common cancers worldwide,and a leading cause of cancer-related death.Owing to unsatisfactory clinical outcomes under the current standard of care,there is a need to search for and identify novel and potent therapeutic targets to improve patient outcomes.Sorafenib is the first and only approved targeted therapy for the treatment of hepatocellular carcinoma.Besides functioning as a multiple tyrosine kinase,sorafenib also acts via a kinase-independent mechanism to target signal transducer and activator of transcription 3(STAT3) signaling in hepatocellular carcinoma cells.STAT3 is a key regulator of inflammation,cell survival,and tumorigenesis of liver cells,and the high percentage of hepatocellular carcinoma cells with constitutively active STAT3 justifies targeting it for the development of novel therapeutics.Sorafenib inactivates STAT3 and STAT3-related signaling by inducing a conformational change in and releasing the autoinhibition of Src homology region 2 domaincontaining phosphatase-1.This phosphatase negatively regulates STAT3 activity,which leads to the subsequent apoptosis of cancer cells.The novel anti-cancer property of sorafenib will be discussed in this review,not only adding information regarding its mechanism of action but also providing an innovative approach for the development of cancer therapeutics in the future.展开更多
Objective: To investigate the effects of Yanghe Pingchuan Granules on airway remodeling in asthmatic rats, and to explore the mechanism of Interleukin-6/Janus kinase 2/ Signal transducing activator of transcription 3(...Objective: To investigate the effects of Yanghe Pingchuan Granules on airway remodeling in asthmatic rats, and to explore the mechanism of Interleukin-6/Janus kinase 2/ Signal transducing activator of transcription 3(IL-6/JAK2/STAT3) signal axis. Methods: We separated 42 healthy male SD rats into two groups, a control group (7) and a model group (35).The model group was sensitized with a combination of ovalbumin (OVA) and aluminum hydroxide for 2 weeks, while the control group was given an equal amount of physiological saline.After 2 weeks, the modeling group was randomly divided into Model group, Yanghe Pingchuan Granules high, medium and low dose groups and Dexamethasone group, each group consisted of 7 animals. After 4 weeks, OVA atomization and gavage were used for stimulation and treatment. Yanghe Pingchuan Granules high, middle and low groups were given 15.48, 7.74, 3.87 g∙kg-1 Yanghe Pingchuan Granules daily, dexamethasone group was given 0.0625 mg∙kg-1 dexamethasone daily, and the other groups were given the same amount of normal saline. HE, PAS and Masson staining were used to observe the lung histopathological changes in rats. The levels of interleukin-6, IL-23 and IL-17A were detected by ELISA. The expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 in lung tissues were detected by Western blot. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the mRNA expression levels of IL-6, JAK2 and STAT3 in rat lung tissue. Results: The lung tissue structure of the model group was severely damaged compared to the control group, accompanied by a great many of inflammatory cell infiltration, goblet cell hyperplasia, subepithelial collagen fiber deposition and airway epithelial thickening were more obvious. The expressions of IL-6, IL- 23 and IL-17A in serum were significantly increased (P<0.01), the protein expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 and the mRNA expression levels of IL-6, JAK2 and STAT3 in lung tissue were significantly increased (P<0.01);Compared with the model group, inflammatory cell infiltration, goblet cell proliferation, subepithelial collagen fiber deposition and airway epithelial thickening were significantly reduced in each administration group, and the expressions of IL-6, IL-23 and IL-17A in serum were significantly decreased (P< 0.01). The protein expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 and mRNA expression levels of IL-6, JAK2 and STAT3 in lung tissue were significantly decreased (P<0.01). Conclusion: Yanghe Pingchuan Granules can significantly alleviate airway remodeling in asthmatic rats, and its mechanism may be through inhibiting the IL-6/JAK2/STAT3 signal axis.展开更多
Objective:To observe the effects of puerarin on the expressions of leptin receptor mRNA and phosphorylated Janus kinase 2 / phosphorylated signal transducers and activators of transcription 3 (P-JAK2/P-STAT3) proteins...Objective:To observe the effects of puerarin on the expressions of leptin receptor mRNA and phosphorylated Janus kinase 2 / phosphorylated signal transducers and activators of transcription 3 (P-JAK2/P-STAT3) proteins in the liver of rats with non-alcoholic fatty liver (NAFLD). Methods: A rat model of NAFLD was successfully established by feeding high-fat diet. All SD rats were randomly divided into blank control group, untreated group, simvastatin-treated group and puerarin-treated group. After four-week treatment, the levels of hepatic triglyceride and total cholesterol were analyzed by using an automatic biochemical analyzer. The pathology of the liver tissue was observed by light microscopy. Serum leptin level was detected by enzyme-linked immunosorbent assay, and the expressions of leptin receptor mRNA and P-JAK2/P-STAT3 proteins in the liver of NAFLD rats were quantified by reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis respectively. Results: Puerarin significantly decreased the levels of hepatic triglyceride and total cholesterol in NAFLD rats. Fat degeneration and inflammatory reaction in liver tissues of NAFLD rats were ameliorated after puerarin treatment. The serum leptin level was increased and the expressions of leptin receptor mRNA and P-JAK2/P-STAT3 proteins were up-regulated in puerarin-treated group. Conclusion: Puerarin can effectively attenuate liver lipid disorder and inflammation by improving the leptin resistance and enhancing the expressions of leptin receptor mRNA and P-JAK2/P-STAT3展开更多
目的:研究Janus激酶(Janus kinase,JAK)抑制剂AG490对人视网膜母细胞瘤HXO-RB44细胞株体外抗增殖及细胞周期的作用,探讨其对JAK2/信号转导与转录激活因子3(signal transducer and activator of transcription 3,STAT3)信号通路蛋白表达...目的:研究Janus激酶(Janus kinase,JAK)抑制剂AG490对人视网膜母细胞瘤HXO-RB44细胞株体外抗增殖及细胞周期的作用,探讨其对JAK2/信号转导与转录激活因子3(signal transducer and activator of transcription 3,STAT3)信号通路蛋白表达的影响。方法:本实验分为实验组和对照组,实验组又根据不同浓度(6.25,12.50,25.00,50.00,100.00,200.00μmol/L)的AG490处理分为6个不同浓度的实验组。采用细胞的活力测定法检测各组细胞增殖状态。应用流式细胞术对各组中细胞凋亡及周期进行分析。采用Western印迹检测处理后STAT3,p-STAT3及血管内皮生长因子(vascular endothelial growth factor,VEGF)蛋白的表达。结果:AG490处理HXO-RB44细胞株48 h后,随着药物浓度的增加,细胞抑制率增加,细胞存活率下降(均P<0.05)。除6.25μmol/L实验组外,其余5组与对照组两两比较,差异均有统计学意义(均P<0.05)。流式细胞术显示:随着AG490药物浓度的增加,细胞凋亡率呈逐渐增高趋势,与对照组相比,差异均有统计学意义(均P<0.05)。其中,50.00和100.00μmol/L实验组G1期细胞比例显著增多,相应地处于S期的细胞比例减少。Western印迹显示:随着AG490药物浓度的增加,STAT3和p-STAT3蛋白的表达量逐渐下降,与对照组相比,差异均有统计学意义(均P<0.05);VEGF表达量逐渐下降,与对照组相比,6.25和12.50μmol/L实验组的VEGF差异均无统计学意义(均P>0.05),其余各实验组差异均有统计学意义(均P<0.05)。结论:JAK抑制剂AG490能抑制HXORB44细胞株生长及增殖,促进细胞的凋亡增加;并通过阻断JAK2/STAT3信号通路而下调STAT3,p-STAT3和VEGF的表达,从而抑制HXO-RB44细胞株的增殖,加速其凋亡。展开更多
基金Supported by the National Natural Science Foundation of China,No.81070319the Beijing Natural Science Foundation of China,No.7102013the Beijing Municipal Education Commission Research Program,China,No.KM201610025004
文摘BACKGROUND Study shows that signal transducer and activator of transcription 3(STAT3) can increase the Warburg effect by stimulating hexokinase 2 in breast cancer and upregulate lactate dehydrogenase A and pyruvate dehydrogenase kinase 1 in myeloma. STAT3 and pyruvate kinase M2(PKM2) can also be activated and enhance the Warburg effect in hepatocellular carcinoma. Precancerous lesions are critical to human and rodent hepatocarcinogenesis. However, the underlying molecular mechanism for the development of liver precancerous lesions remains unknown. We hypothesized that STAT3 promotes the Warburg effect possibly by upregulating p-PKM2 in liver precancerous lesions in rats.AIM To investigate the mechanism of the Warburg effect in liver precancerous lesions in rats.METHODS A model of liver precancerous lesions was established by a modified Solt-Farber method. The liver pathological changes were observed by HE staining and immunohistochemistry. The transformation of WB-F344 cells induced with Nmethyl-N'-nitro-N-nitrosoguanidine and hydrogen peroxide was evaluated by the soft agar assay and aneuploidy. The levels of glucose and lactate in the tissue and culture medium were detected with a spectrophotometer. The protein levels of glutathione S-transferase-π, proliferating cell nuclear antigen(PCNA), STAT3,and PKM2 were examined by Western blot and immunofluorescence.RESULTS We found that the Warburg effect was increased in liver precancerous lesions in rats. PKM2 and p-STAT3 were upregulated in activated oval cells in liverprecancerous lesions in rats. The Warburg effect, p-PKM2, and p-STAT3 expression were also increased in transformed WB-F344 cells. STAT3 activation promoted the clonal formation rate, aneuploidy, alpha-fetoprotein expression,PCNA expression, G1/S phase transition, the Warburg effect, PKM2 phosphorylation, and nuclear translocation in transformed WB-F344 cells.Moreover, the Warburg effect was inhibited by stattic, a specific inhibitor of STAT3, and further reduced in transformed WB-F344 cells after the intervention for PKM2.CONCLUSION The Warburg effect is initiated in liver precancerous lesions in rats. STAT3 activation promotes the Warburg effect by enhancing the phosphorylation of PKM2 in transformed WB-F344 cells.
文摘The Janus kinase and signal transducer and activator of transcription （JAK/STAT） signal transduction pathway is involved in sepsis-induced functional damage to the heart, liver, kidney, and other organs. However, the cellular and molecular mechanisms underlying sepsis-induced brain damage remain elusive. In the present study, we found severe loss of neurons in the hippocampal CA1 region in rats with sepsis-induced brain damage following intraperitoneal injection of endotoxin, The expression of toll-like receptor 4, tumor necrosis factor a, and interleukin-6 was significantly increased in brain tissues following lipopolysaccharide exposure. AG490 （JAK2 antagonist） and rapamycin （STAT3 antagonist） significantly reduced neuronal loss and suppressed the increased expression of toll-like receptor 4, tumor necrosis factor a, and interleukin-6 in the hippocampal CA1 region in sepsis-induced brain damaged rats. Overall, these data suggest that blockade of the JAK/STAT signal transduction pathway is neuroprotective in sepsis-induced brain damage via the inhibition of toll-like receptor 4, tumor necrosis factor a, and interleukin-6 exoression.
文摘Hepatocellular carcinoma is one of the most common cancers worldwide,and a leading cause of cancer-related death.Owing to unsatisfactory clinical outcomes under the current standard of care,there is a need to search for and identify novel and potent therapeutic targets to improve patient outcomes.Sorafenib is the first and only approved targeted therapy for the treatment of hepatocellular carcinoma.Besides functioning as a multiple tyrosine kinase,sorafenib also acts via a kinase-independent mechanism to target signal transducer and activator of transcription 3(STAT3) signaling in hepatocellular carcinoma cells.STAT3 is a key regulator of inflammation,cell survival,and tumorigenesis of liver cells,and the high percentage of hepatocellular carcinoma cells with constitutively active STAT3 justifies targeting it for the development of novel therapeutics.Sorafenib inactivates STAT3 and STAT3-related signaling by inducing a conformational change in and releasing the autoinhibition of Src homology region 2 domaincontaining phosphatase-1.This phosphatase negatively regulates STAT3 activity,which leads to the subsequent apoptosis of cancer cells.The novel anti-cancer property of sorafenib will be discussed in this review,not only adding information regarding its mechanism of action but also providing an innovative approach for the development of cancer therapeutics in the future.
基金The Sixth Batch of Special Support Plans in Anhui Province(No.dlPtzjh20200050)Key Natural Science Research Project of Higher Education Institutions in Anhui Province(No.KJ2020A0426)。
文摘Objective: To investigate the effects of Yanghe Pingchuan Granules on airway remodeling in asthmatic rats, and to explore the mechanism of Interleukin-6/Janus kinase 2/ Signal transducing activator of transcription 3(IL-6/JAK2/STAT3) signal axis. Methods: We separated 42 healthy male SD rats into two groups, a control group (7) and a model group (35).The model group was sensitized with a combination of ovalbumin (OVA) and aluminum hydroxide for 2 weeks, while the control group was given an equal amount of physiological saline.After 2 weeks, the modeling group was randomly divided into Model group, Yanghe Pingchuan Granules high, medium and low dose groups and Dexamethasone group, each group consisted of 7 animals. After 4 weeks, OVA atomization and gavage were used for stimulation and treatment. Yanghe Pingchuan Granules high, middle and low groups were given 15.48, 7.74, 3.87 g∙kg-1 Yanghe Pingchuan Granules daily, dexamethasone group was given 0.0625 mg∙kg-1 dexamethasone daily, and the other groups were given the same amount of normal saline. HE, PAS and Masson staining were used to observe the lung histopathological changes in rats. The levels of interleukin-6, IL-23 and IL-17A were detected by ELISA. The expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 in lung tissues were detected by Western blot. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the mRNA expression levels of IL-6, JAK2 and STAT3 in rat lung tissue. Results: The lung tissue structure of the model group was severely damaged compared to the control group, accompanied by a great many of inflammatory cell infiltration, goblet cell hyperplasia, subepithelial collagen fiber deposition and airway epithelial thickening were more obvious. The expressions of IL-6, IL- 23 and IL-17A in serum were significantly increased (P<0.01), the protein expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 and the mRNA expression levels of IL-6, JAK2 and STAT3 in lung tissue were significantly increased (P<0.01);Compared with the model group, inflammatory cell infiltration, goblet cell proliferation, subepithelial collagen fiber deposition and airway epithelial thickening were significantly reduced in each administration group, and the expressions of IL-6, IL-23 and IL-17A in serum were significantly decreased (P< 0.01). The protein expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 and mRNA expression levels of IL-6, JAK2 and STAT3 in lung tissue were significantly decreased (P<0.01). Conclusion: Yanghe Pingchuan Granules can significantly alleviate airway remodeling in asthmatic rats, and its mechanism may be through inhibiting the IL-6/JAK2/STAT3 signal axis.
文摘Objective:To observe the effects of puerarin on the expressions of leptin receptor mRNA and phosphorylated Janus kinase 2 / phosphorylated signal transducers and activators of transcription 3 (P-JAK2/P-STAT3) proteins in the liver of rats with non-alcoholic fatty liver (NAFLD). Methods: A rat model of NAFLD was successfully established by feeding high-fat diet. All SD rats were randomly divided into blank control group, untreated group, simvastatin-treated group and puerarin-treated group. After four-week treatment, the levels of hepatic triglyceride and total cholesterol were analyzed by using an automatic biochemical analyzer. The pathology of the liver tissue was observed by light microscopy. Serum leptin level was detected by enzyme-linked immunosorbent assay, and the expressions of leptin receptor mRNA and P-JAK2/P-STAT3 proteins in the liver of NAFLD rats were quantified by reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis respectively. Results: Puerarin significantly decreased the levels of hepatic triglyceride and total cholesterol in NAFLD rats. Fat degeneration and inflammatory reaction in liver tissues of NAFLD rats were ameliorated after puerarin treatment. The serum leptin level was increased and the expressions of leptin receptor mRNA and P-JAK2/P-STAT3 proteins were up-regulated in puerarin-treated group. Conclusion: Puerarin can effectively attenuate liver lipid disorder and inflammation by improving the leptin resistance and enhancing the expressions of leptin receptor mRNA and P-JAK2/P-STAT3
