Polypeptide from Chlamys farreri(PCF) is a novel marine bioactive product that was isolated from the gonochoric Chinese scallop Chlamys farreri,and was found to be an effective antioxidant in our recent studies.In thi...Polypeptide from Chlamys farreri(PCF) is a novel marine bioactive product that was isolated from the gonochoric Chinese scallop Chlamys farreri,and was found to be an effective antioxidant in our recent studies.In this study,we investigated the effect of PCF on ultraviolet B(UVB)-induced apoptosis of HaCaT cells and the intracellular signaling pathways involved.Pretreatment with the inducible nitric oxide synthase(iNOS) inhibitor S-methylisothiourea sulfate inhibited UVB-induced apoptosis,indicating that iNOS and NO play important roles in apoptosis.On the other hand,the inhibition of UVB-induced apoptosis in the immortalized keratinocyte(HaCaT) cells by PCF was estimated using a DNA ladder.PCF treatment inhibited UVB-induced iNOS activation,as determined by RT-PCR,NO production,as determined by ESR,and up-regulated heat shock protein(HSP) 90 activation,as determined by Western blotting.Our results indicate that iNOS and NO are involved in UVB-induced apoptosis of HaCaT cells and the protective effect of PCF against UVB irradiation is exerted by suppressing the expression of iNOS,followed by inhibition of NO release and enhanced activation of HSP90.展开更多
Early life exposure to adverse conditions such as social life issues, economic problems, health issues, death and separation of loved ones produces stress. Stressful life events (SLEs) disturb the healthy quality of l...Early life exposure to adverse conditions such as social life issues, economic problems, health issues, death and separation of loved ones produces stress. Stressful life events (SLEs) disturb the healthy quality of life in multiple ways. The biological response to SLE includes the production and activation of stress hormones. It has been reported that adrenaline, noradrenalin, pituitary, cortisol, prolactin, growth and adrenocorticotropic hormones are responsive to SLE. It is observed that under psychological stress, the circulating level of cortisol and norepinephrine (NE) is higher than in normal subjects. Under stress glucocorticoids (GC), neuroendocrine, norepinephrine and catecholamine produce reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS cause oxidative damage and lower antioxidant capacity and protection. Persistent damaged DNA may lead to the initiation of cancer. It is said that the risk factor of immune dysfunction and cancer may be increased under stress conditions by regulation of iNOS. iNOS is most widely studied as it produces large amounts of nitric oxide which affects many vital processes including apoptosis and angiogenesis in leukemia cells. The regulation of the expression of iNOS is important to control the level of reactive oxygen and nitrogen species that can be lethal to the cell and its environment. It is reported that the microenvironment of a cell affects the expression of iNOS. Therefore, it is concluded that different cells breast, colon, esophagus, bladder, lung, oral cavity and prostate might show different expressions of iNOS. Expression of iNOS is higher in tumor cells than in normal controls. Different studies have been conducted to explore the relationship between iNOS and cancer. The aim of this study is to investigate the expression of iNOS in acute lymphocytic leukemia under stress conditions. The study was performed on ALL blood samples under stress and non-stressed conditions. Polymerase chain reaction (PCR) was performed and gene- specific primers were used to see the iNOS expression. The study showed that expression of iNOS is higher in the patient than in control under stress while non-stressed patients showed significant reduction in iNOS expression. Further research is required to validate the importance of psychological factors and iNOS in cancer.展开更多
基金Supported by the National Natural Science Foundation of China (30471458)National Natural Science Foundation of Shandong Province (Z2007c09)
文摘Polypeptide from Chlamys farreri(PCF) is a novel marine bioactive product that was isolated from the gonochoric Chinese scallop Chlamys farreri,and was found to be an effective antioxidant in our recent studies.In this study,we investigated the effect of PCF on ultraviolet B(UVB)-induced apoptosis of HaCaT cells and the intracellular signaling pathways involved.Pretreatment with the inducible nitric oxide synthase(iNOS) inhibitor S-methylisothiourea sulfate inhibited UVB-induced apoptosis,indicating that iNOS and NO play important roles in apoptosis.On the other hand,the inhibition of UVB-induced apoptosis in the immortalized keratinocyte(HaCaT) cells by PCF was estimated using a DNA ladder.PCF treatment inhibited UVB-induced iNOS activation,as determined by RT-PCR,NO production,as determined by ESR,and up-regulated heat shock protein(HSP) 90 activation,as determined by Western blotting.Our results indicate that iNOS and NO are involved in UVB-induced apoptosis of HaCaT cells and the protective effect of PCF against UVB irradiation is exerted by suppressing the expression of iNOS,followed by inhibition of NO release and enhanced activation of HSP90.
文摘Early life exposure to adverse conditions such as social life issues, economic problems, health issues, death and separation of loved ones produces stress. Stressful life events (SLEs) disturb the healthy quality of life in multiple ways. The biological response to SLE includes the production and activation of stress hormones. It has been reported that adrenaline, noradrenalin, pituitary, cortisol, prolactin, growth and adrenocorticotropic hormones are responsive to SLE. It is observed that under psychological stress, the circulating level of cortisol and norepinephrine (NE) is higher than in normal subjects. Under stress glucocorticoids (GC), neuroendocrine, norepinephrine and catecholamine produce reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS cause oxidative damage and lower antioxidant capacity and protection. Persistent damaged DNA may lead to the initiation of cancer. It is said that the risk factor of immune dysfunction and cancer may be increased under stress conditions by regulation of iNOS. iNOS is most widely studied as it produces large amounts of nitric oxide which affects many vital processes including apoptosis and angiogenesis in leukemia cells. The regulation of the expression of iNOS is important to control the level of reactive oxygen and nitrogen species that can be lethal to the cell and its environment. It is reported that the microenvironment of a cell affects the expression of iNOS. Therefore, it is concluded that different cells breast, colon, esophagus, bladder, lung, oral cavity and prostate might show different expressions of iNOS. Expression of iNOS is higher in tumor cells than in normal controls. Different studies have been conducted to explore the relationship between iNOS and cancer. The aim of this study is to investigate the expression of iNOS in acute lymphocytic leukemia under stress conditions. The study was performed on ALL blood samples under stress and non-stressed conditions. Polymerase chain reaction (PCR) was performed and gene- specific primers were used to see the iNOS expression. The study showed that expression of iNOS is higher in the patient than in control under stress while non-stressed patients showed significant reduction in iNOS expression. Further research is required to validate the importance of psychological factors and iNOS in cancer.
