Bone remodeling is performed under the joint action of osteoblasts and osteoclasts. Since the effect of osteoclasts has been gradually recognized on bone and joint diseases, targeted researches toward osteoclasts have...Bone remodeling is performed under the joint action of osteoblasts and osteoclasts. Since the effect of osteoclasts has been gradually recognized on bone and joint diseases, targeted researches toward osteoclasts have become a hot research field. This article reviews the relevant medical literature concerning the possible effects of the fluid shear stress (FSS) on the osteoclastogenesis chiefly from the aspects of RANKL-RANK-OPG system, the macrophage colony-stimulating factor (M-CSF), and calcitonin receptor (CTR). On the basis of the changes of the expression of osteoclastic activities, it is suggested that FSS is a potent, important regulator of bone metabolism.展开更多
Estrogen deficiency has been proposed as a risk factor for alveolar bone loss, but whether or not estrogen will influcence the bone rebuilting process during orthodontic tooth movement and what the mechanisms involved...Estrogen deficiency has been proposed as a risk factor for alveolar bone loss, but whether or not estrogen will influcence the bone rebuilting process during orthodontic tooth movement and what the mechanisms involved remain unclear. The paper aims to provide new information that may elucidate the modulatory effect of estrogen on the bone-resorbing cytokines RANKL and its anti-resorptive factor OPG secrected by HPLFs which are already force-stimulated. The expression of OPG mRNA is rising after mechanical loading either with or without stimulated by estrogen before. But HPDL cells exposured to estrogen for 24 h before loaded tend to express more OPG mRNA. Compared with the no-estrogen group, the inhibit trend of RANKL mRNA is much more apparent in with-estrogen group. Moreover, estrogen and mechanic force time-dependently increased OPG expression and attenuated the RANKL expression.展开更多
Objective To study the effect of the serum derived from the rats treated with electroacupunctre at Stomach Meridian acupoints on the EGFR signal transduction pathway in gastric mucosal cells. Methods Sixty rats were r...Objective To study the effect of the serum derived from the rats treated with electroacupunctre at Stomach Meridian acupoints on the EGFR signal transduction pathway in gastric mucosal cells. Methods Sixty rats were randomly divided into 5 groups： model group, Stomach （ST） Meridian group, Gallbladder （GB） Meridian group, ST＋ PD153035 group and GB＋ PD153035 group. Water-immersion and restrained stress method was adopted for preparation of the stress-induced gastric ulcer rat model, and the gastric mucosa cells were separated by using pronase digestion method. Gastric mucosa cells were incubated respectively with PD153035, EGFR inhibitor and the serum; PLCγ-1＇s expression level in gastric mucosa cells was tested by enzyme-linked immunosorbant assay （ELISA）, and PKC activity by isotope mingling method; and reverse transcription polymerase chain reaction assay （RT-PCR） was used for testing expression level of c-myc gene. Results The expression levels of PLCγ-1 ,PKC and c- myc gene were lower in gastric mucosa cells in the model group; there were relatively high expression levels of PLCγ-1 ,PKC and c-myc gene in the ST Meridian group and the GB Meridian group, with the highest expression levels of PLCγ-1 ,PKC and c-myc gene in the ST Meridian, and with a significant difference between the ST Meridian group and the GB Meridian group （P〈0.01 ） ; and relative lower expression levels of PLCγ-1, PKC and c-myc gene were seen in the ST ＋ PD153035 group and the GB ＋ PD153035 group; and there was a significant difference between the ST Meridian group and the ST ＋ PD153035 group （P〈0.01）. Conclusion There was a close correlation between the healing effect of electroacupuncture and activation of the EGFR signal transduction pathway in the impaired gastric mucosa cells, which was also one proof for the TCM theory： ＂There is relative specificity between the meridians and viscera＂.展开更多
Since the discovery of leptin as an adipokine in 1994, much progress has been made in the research about leptin. Circulating leptin binds to leptin receptor, activates STAT3-dependent and STAT3-independent signaling p...Since the discovery of leptin as an adipokine in 1994, much progress has been made in the research about leptin. Circulating leptin binds to leptin receptor, activates STAT3-dependent and STAT3-independent signaling pathways, and plays an effective role in energy home- ostasis, neuroendocrine function and metabolism mainly through acting on the central nervous system, especially the hypothalamus. Leptin resistance is considered as a key risk factor for obesity. Various mechanisms have been formu- lated in order to explain leptin resistance, including impairment in leptin transport, attenuation in leptin sig- naling, ER stress, inflammation and deficiency in autop- hagy. Here, we review our current knowledge about leptin action, leptin signaling and leptin resistance, hoping to provide new ideas for the battle against obesity.展开更多
Quercetin, a phenolic phytochemical widely present in vegetables and fruits, has antioxidant, anti-inflammatory, antiviral, and immunomodulatory activities, and it has been successfully used in the treatment of acute ...Quercetin, a phenolic phytochemical widely present in vegetables and fruits, has antioxidant, anti-inflammatory, antiviral, and immunomodulatory activities, and it has been successfully used in the treatment of acute and chronic diseases. In the present study, we aimed to investigate the alleviation effect of quercetin on rat liver fibrosis and explore its mechanism of action. Healthy male SD rats were randomly divided into the normal group, model group, and quercetin group, with six rats in each group. Liver fibrosis was induced by intraperitoneal injection of 1 m L/kg carbon tetrachloride(50% v/v in olive oil) twice a week for 6 weeks, and quercetin(100 mg/kg/d) was administered orally in the 7th week until the end of the 12th week. Blood and liver samples were collected at 1 h after the last administration. Serum liver function parameters(AST, ALT, ALP, GGT, and TBA) were detected by an automatic biochemical analyzer. H&E, Masson, and Sirius red staining were used to observe the pathological morphology of liver tissue. Western blotting analysis was used to evaluate the expressions of liver fibrotic factors(TGF-β1, α-SMA, MMP2, and MMP9) and bile acid-related regulatory proteins(FXR, CYP7A1, CYP8B1, and CYP27A1). The oxidative stress markers(GSH, GSH-Px, GR, SOD, and MDA) in the liver tissue were detected using corresponding kits. The contents of bile acids in the liver tissue were determined by LC-MS/MS. The results showed that compared with the model group, quercetin treatment could significantly reduce serum AST, ALT, and TBA levels(P < 0.05). The fibrotic liver injury was significantly improved, and the expressions of fibrotic factors TGF-β1, α-SMA, MMP2, and MMP9 were significantly decreased(P < 0.05). Liver GSH, GSH-Px, GR, and SOD levels were significantly increased(P < 0.05), and the MDA level was significantly decreased(P < 0.05). The contents of hepatic bile acids were significantly decreased(P < 0.05), the expression of FXR was significantly increased(P < 0.05), and the expressions of CYP7A1 and CYP8B1 were significantly decreased(P < 0.05). This study suggested that quercetin could effectively alleviate carbon tetrachloride-induced liver fibrosis injury, and its mechanism of action was related to improving the liver’s ability to resist oxidative stress and reducing the expressions of fibrotic factors and bile acid synthesis.展开更多
文摘Bone remodeling is performed under the joint action of osteoblasts and osteoclasts. Since the effect of osteoclasts has been gradually recognized on bone and joint diseases, targeted researches toward osteoclasts have become a hot research field. This article reviews the relevant medical literature concerning the possible effects of the fluid shear stress (FSS) on the osteoclastogenesis chiefly from the aspects of RANKL-RANK-OPG system, the macrophage colony-stimulating factor (M-CSF), and calcitonin receptor (CTR). On the basis of the changes of the expression of osteoclastic activities, it is suggested that FSS is a potent, important regulator of bone metabolism.
文摘Estrogen deficiency has been proposed as a risk factor for alveolar bone loss, but whether or not estrogen will influcence the bone rebuilting process during orthodontic tooth movement and what the mechanisms involved remain unclear. The paper aims to provide new information that may elucidate the modulatory effect of estrogen on the bone-resorbing cytokines RANKL and its anti-resorptive factor OPG secrected by HPLFs which are already force-stimulated. The expression of OPG mRNA is rising after mechanical loading either with or without stimulated by estrogen before. But HPDL cells exposured to estrogen for 24 h before loaded tend to express more OPG mRNA. Compared with the no-estrogen group, the inhibit trend of RANKL mRNA is much more apparent in with-estrogen group. Moreover, estrogen and mechanic force time-dependently increased OPG expression and attenuated the RANKL expression.
基金Supported by the Natural Science Foundation of Jiangxi Province (No :2008 GZY0022)the Technology Plan of Jiangxi Provincial Department of Education (No :GJJ09280)
文摘Objective To study the effect of the serum derived from the rats treated with electroacupunctre at Stomach Meridian acupoints on the EGFR signal transduction pathway in gastric mucosal cells. Methods Sixty rats were randomly divided into 5 groups： model group, Stomach （ST） Meridian group, Gallbladder （GB） Meridian group, ST＋ PD153035 group and GB＋ PD153035 group. Water-immersion and restrained stress method was adopted for preparation of the stress-induced gastric ulcer rat model, and the gastric mucosa cells were separated by using pronase digestion method. Gastric mucosa cells were incubated respectively with PD153035, EGFR inhibitor and the serum; PLCγ-1＇s expression level in gastric mucosa cells was tested by enzyme-linked immunosorbant assay （ELISA）, and PKC activity by isotope mingling method; and reverse transcription polymerase chain reaction assay （RT-PCR） was used for testing expression level of c-myc gene. Results The expression levels of PLCγ-1 ,PKC and c- myc gene were lower in gastric mucosa cells in the model group; there were relatively high expression levels of PLCγ-1 ,PKC and c-myc gene in the ST Meridian group and the GB Meridian group, with the highest expression levels of PLCγ-1 ,PKC and c-myc gene in the ST Meridian, and with a significant difference between the ST Meridian group and the GB Meridian group （P〈0.01 ） ; and relative lower expression levels of PLCγ-1, PKC and c-myc gene were seen in the ST ＋ PD153035 group and the GB ＋ PD153035 group; and there was a significant difference between the ST Meridian group and the ST ＋ PD153035 group （P〈0.01）. Conclusion There was a close correlation between the healing effect of electroacupuncture and activation of the EGFR signal transduction pathway in the impaired gastric mucosa cells, which was also one proof for the TCM theory： ＂There is relative specificity between the meridians and viscera＂.
基金Acknowledgments This work was supported by the National Basic Research Program of China （2013CB530601, 2011CB910201）, the National Natural Science Foundation of China （31571401, 81270954, 31030048, 81390350）, the Shanghai Rising Star Program （13QH1400800）. The Department of Biochemistry and Molecular Biology at Fudan University Shanghai Medical College is supported by the Shanghai Leading Academic Discipline Projects B 110 and by ＂985＂ Project 985III-YFX0302.
文摘Since the discovery of leptin as an adipokine in 1994, much progress has been made in the research about leptin. Circulating leptin binds to leptin receptor, activates STAT3-dependent and STAT3-independent signaling pathways, and plays an effective role in energy home- ostasis, neuroendocrine function and metabolism mainly through acting on the central nervous system, especially the hypothalamus. Leptin resistance is considered as a key risk factor for obesity. Various mechanisms have been formu- lated in order to explain leptin resistance, including impairment in leptin transport, attenuation in leptin sig- naling, ER stress, inflammation and deficiency in autop- hagy. Here, we review our current knowledge about leptin action, leptin signaling and leptin resistance, hoping to provide new ideas for the battle against obesity.
基金Natural Science Foundations of China (Grant No. 81960680)Lanzhou Chengguan District Science and Technology Project (Grant No. 2019RCCX0039)Intra-hospital Fund of the First Hospital of Lanzhou University (Grant No. ldyyyn2018-10),China。
文摘Quercetin, a phenolic phytochemical widely present in vegetables and fruits, has antioxidant, anti-inflammatory, antiviral, and immunomodulatory activities, and it has been successfully used in the treatment of acute and chronic diseases. In the present study, we aimed to investigate the alleviation effect of quercetin on rat liver fibrosis and explore its mechanism of action. Healthy male SD rats were randomly divided into the normal group, model group, and quercetin group, with six rats in each group. Liver fibrosis was induced by intraperitoneal injection of 1 m L/kg carbon tetrachloride(50% v/v in olive oil) twice a week for 6 weeks, and quercetin(100 mg/kg/d) was administered orally in the 7th week until the end of the 12th week. Blood and liver samples were collected at 1 h after the last administration. Serum liver function parameters(AST, ALT, ALP, GGT, and TBA) were detected by an automatic biochemical analyzer. H&E, Masson, and Sirius red staining were used to observe the pathological morphology of liver tissue. Western blotting analysis was used to evaluate the expressions of liver fibrotic factors(TGF-β1, α-SMA, MMP2, and MMP9) and bile acid-related regulatory proteins(FXR, CYP7A1, CYP8B1, and CYP27A1). The oxidative stress markers(GSH, GSH-Px, GR, SOD, and MDA) in the liver tissue were detected using corresponding kits. The contents of bile acids in the liver tissue were determined by LC-MS/MS. The results showed that compared with the model group, quercetin treatment could significantly reduce serum AST, ALT, and TBA levels(P < 0.05). The fibrotic liver injury was significantly improved, and the expressions of fibrotic factors TGF-β1, α-SMA, MMP2, and MMP9 were significantly decreased(P < 0.05). Liver GSH, GSH-Px, GR, and SOD levels were significantly increased(P < 0.05), and the MDA level was significantly decreased(P < 0.05). The contents of hepatic bile acids were significantly decreased(P < 0.05), the expression of FXR was significantly increased(P < 0.05), and the expressions of CYP7A1 and CYP8B1 were significantly decreased(P < 0.05). This study suggested that quercetin could effectively alleviate carbon tetrachloride-induced liver fibrosis injury, and its mechanism of action was related to improving the liver’s ability to resist oxidative stress and reducing the expressions of fibrotic factors and bile acid synthesis.
