In nature, plants constantly have to face pathogen attacks. However, plant disease rarely occurs due to efficient immune systems possessed by the host plants. Pathogens are perceived by two different recognition syste...In nature, plants constantly have to face pathogen attacks. However, plant disease rarely occurs due to efficient immune systems possessed by the host plants. Pathogens are perceived by two different recognition systems that initiate the so-called pattern-triggered immunity (PTI) and effector-triggered immunity (ETI), both of which are accompanied by a set of induced defenses that usually repel pathogen attacks. Here we discuss the complex network of signaling pathways occurring during PTI, focusing on the involvement of mitogen-activated protein kinases.展开更多
Liver diseases are caused by different etiological agents, mainly alcohol consumption, viruses, drug intoxication or malnutrition. Frequently, liver diseases are initiated by oxidative stress and inflammation that lea...Liver diseases are caused by different etiological agents, mainly alcohol consumption, viruses, drug intoxication or malnutrition. Frequently, liver diseases are initiated by oxidative stress and inflammation that lead to the excessive production of extracellular matrix(ECM), followed by a progression to fibrosis, cirrhosis and hepatocellular carcinoma(HCC). It has been reported that some natural products display hepatoprotective properties. Naringenin is a flavonoid with antioxidant, antifibrogenic, anti-inflammatory and anticancer properties that is capable of preventing liver damage caused by different agents. The main protective effects of naringenin in liver diseases are the inhibition of oxidative stress, transforming growth factor(TGF-β) pathway and the prevention of the transdifferentiation of hepatic stellate cells(HSC), leading to decreased collagen synthesis. Other effects include the inhibition of the mitogen activated protein kinase(MAPK), toll-like receptor(TLR) and TGF-β non-canonical pathways, the inhibition of which further results in a strong reduction in ECM synthesis and deposition. In addition, naringenin has shown beneficial effects on nonalcoholic fatty liver disease(NAFLD) through the regulation of lipid metabolism, modulating the synthesis and oxidation of lipids and cholesterol. Moreover, naringenin protects from HCC, since it inhibits growth factors such as TGF-β and vascular endothelial growth factor(VEGF), inducing apoptosis and regulating MAPK pathways. Naringenin is safe and acts by targeting multiple proteins. However, it possesses low bioavailability and high intestinal metabolism. In this regard, formulations, such as nanoparticles or liposomes, have been developed to improve naringenin bioavailability. We conclude that naringenin should be considered in the future as an important candidate in the treatment of different liver diseases.展开更多
丝裂原活化蛋白激酶(mitogen-actived protein kinase,MAPK)是真核生物信号传递网络中的重要途径之一,在基因表达调控和细胞质功能活动中发挥关键作用。在哺乳动物机体中,5种不同的MAPK信号转导通路中ERK1/2信号转导通路调控细胞生长和...丝裂原活化蛋白激酶(mitogen-actived protein kinase,MAPK)是真核生物信号传递网络中的重要途径之一,在基因表达调控和细胞质功能活动中发挥关键作用。在哺乳动物机体中,5种不同的MAPK信号转导通路中ERK1/2信号转导通路调控细胞生长和分化,JNK和p38MAPK信号转导通路在炎症与细胞凋亡等应激反应中发挥重要作用。信号转导途径的活化是类风湿性关节炎(rheumatoid arthritis,RA)慢性滑膜炎的典型特征,通过这一途径诱导滑膜细胞胞质蛋白磷酸化,使转录因子和核蛋白如c-Fos、c-Jun、AP-1和NF-κB等磷酸化,从而促进细胞增殖和活化。上述机制研究对于RA发病机制的深入了解以及研制开发治疗RA的新型药物具有重要的意义。展开更多
Simple regulation of c-Jun N-terminal kinase(JNK) or p38 mitogen-activated protein kinase(MAPK) pathways is not enough to trigger cell apoptosis.However,activation of the stress activated pathway(JNK/p38 MAPK) t...Simple regulation of c-Jun N-terminal kinase(JNK) or p38 mitogen-activated protein kinase(MAPK) pathways is not enough to trigger cell apoptosis.However,activation of the stress activated pathway(JNK/p38 MAPK) together with inhibition of the growth factor activated extracellular signal-regulated kinase(ERK) pathway can promote cell apoptosis.We hypothesized that inhibition of the JNK or p38 pro-apoptotic pathway and activating the ERK pathway could be the mechanism of anti-apoptosis following cerebral ischemia/reperfusion injury.To investigate the mechanism of the protective effect of electroacupuncture on cerebral ischemia/reperfusion injury in JNK knockout mice,mouse models of cerebral ischemia/reperfusion injury were established by Longa’s method.Electroacupuncture was conducted at acupoints Chize(LU5),Hegu(LI4),Sanyinjiao(SP6) and Zusanli(ST36) 1.5 hours after ischemia/reperfusion injury for 20 minutes,once a day.The neurological function was evaluated using neurological deficit scores.The expression of phospho-extracellular signal-regulated kinase(p-ERK) and phospho-p38(p-p38) in JNK knockout mice was detected using double-labeling immunofluorescence and western blot assay.The m RNA expression of ERK and p38 was measured by quantitative real-time polymerase chain reaction.Electroacupuncture improved neurological function,increased the immunoreactivity and relative expression of p-ERK and reduced that of p-p38 in the cerebral cortex and hippocampus on the injured side.Electroacupuncture increased m RNA expression of ERK,but decreased that of p38 in the cerebral cortex and hippocampus on the injured side.In conclusion,electroacupuncture upregulated the protective ERK pathway and inhibited the pro-apoptotic p38 pathway,thereby exerting a neuroprotective effect and improving the neurological function in JNK knockout mice.展开更多
文摘In nature, plants constantly have to face pathogen attacks. However, plant disease rarely occurs due to efficient immune systems possessed by the host plants. Pathogens are perceived by two different recognition systems that initiate the so-called pattern-triggered immunity (PTI) and effector-triggered immunity (ETI), both of which are accompanied by a set of induced defenses that usually repel pathogen attacks. Here we discuss the complex network of signaling pathways occurring during PTI, focusing on the involvement of mitogen-activated protein kinases.
基金Supported by National Council of Science and Technology(Conacyt)of Mexico,No.253037
文摘Liver diseases are caused by different etiological agents, mainly alcohol consumption, viruses, drug intoxication or malnutrition. Frequently, liver diseases are initiated by oxidative stress and inflammation that lead to the excessive production of extracellular matrix(ECM), followed by a progression to fibrosis, cirrhosis and hepatocellular carcinoma(HCC). It has been reported that some natural products display hepatoprotective properties. Naringenin is a flavonoid with antioxidant, antifibrogenic, anti-inflammatory and anticancer properties that is capable of preventing liver damage caused by different agents. The main protective effects of naringenin in liver diseases are the inhibition of oxidative stress, transforming growth factor(TGF-β) pathway and the prevention of the transdifferentiation of hepatic stellate cells(HSC), leading to decreased collagen synthesis. Other effects include the inhibition of the mitogen activated protein kinase(MAPK), toll-like receptor(TLR) and TGF-β non-canonical pathways, the inhibition of which further results in a strong reduction in ECM synthesis and deposition. In addition, naringenin has shown beneficial effects on nonalcoholic fatty liver disease(NAFLD) through the regulation of lipid metabolism, modulating the synthesis and oxidation of lipids and cholesterol. Moreover, naringenin protects from HCC, since it inhibits growth factors such as TGF-β and vascular endothelial growth factor(VEGF), inducing apoptosis and regulating MAPK pathways. Naringenin is safe and acts by targeting multiple proteins. However, it possesses low bioavailability and high intestinal metabolism. In this regard, formulations, such as nanoparticles or liposomes, have been developed to improve naringenin bioavailability. We conclude that naringenin should be considered in the future as an important candidate in the treatment of different liver diseases.
文摘丝裂原活化蛋白激酶(mitogen-actived protein kinase,MAPK)是真核生物信号传递网络中的重要途径之一,在基因表达调控和细胞质功能活动中发挥关键作用。在哺乳动物机体中,5种不同的MAPK信号转导通路中ERK1/2信号转导通路调控细胞生长和分化,JNK和p38MAPK信号转导通路在炎症与细胞凋亡等应激反应中发挥重要作用。信号转导途径的活化是类风湿性关节炎(rheumatoid arthritis,RA)慢性滑膜炎的典型特征,通过这一途径诱导滑膜细胞胞质蛋白磷酸化,使转录因子和核蛋白如c-Fos、c-Jun、AP-1和NF-κB等磷酸化,从而促进细胞增殖和活化。上述机制研究对于RA发病机制的深入了解以及研制开发治疗RA的新型药物具有重要的意义。
基金supported by the National Natural Science Foundation of China,No.81173355
文摘Simple regulation of c-Jun N-terminal kinase(JNK) or p38 mitogen-activated protein kinase(MAPK) pathways is not enough to trigger cell apoptosis.However,activation of the stress activated pathway(JNK/p38 MAPK) together with inhibition of the growth factor activated extracellular signal-regulated kinase(ERK) pathway can promote cell apoptosis.We hypothesized that inhibition of the JNK or p38 pro-apoptotic pathway and activating the ERK pathway could be the mechanism of anti-apoptosis following cerebral ischemia/reperfusion injury.To investigate the mechanism of the protective effect of electroacupuncture on cerebral ischemia/reperfusion injury in JNK knockout mice,mouse models of cerebral ischemia/reperfusion injury were established by Longa’s method.Electroacupuncture was conducted at acupoints Chize(LU5),Hegu(LI4),Sanyinjiao(SP6) and Zusanli(ST36) 1.5 hours after ischemia/reperfusion injury for 20 minutes,once a day.The neurological function was evaluated using neurological deficit scores.The expression of phospho-extracellular signal-regulated kinase(p-ERK) and phospho-p38(p-p38) in JNK knockout mice was detected using double-labeling immunofluorescence and western blot assay.The m RNA expression of ERK and p38 was measured by quantitative real-time polymerase chain reaction.Electroacupuncture improved neurological function,increased the immunoreactivity and relative expression of p-ERK and reduced that of p-p38 in the cerebral cortex and hippocampus on the injured side.Electroacupuncture increased m RNA expression of ERK,but decreased that of p38 in the cerebral cortex and hippocampus on the injured side.In conclusion,electroacupuncture upregulated the protective ERK pathway and inhibited the pro-apoptotic p38 pathway,thereby exerting a neuroprotective effect and improving the neurological function in JNK knockout mice.