Biological rhythms controlled by the circadian clock are absent in embryonic stem cells (ESCs). However, they start to develop during the differentiation of pluripotent ESCs to downstream cells. Conversely, biologic...Biological rhythms controlled by the circadian clock are absent in embryonic stem cells (ESCs). However, they start to develop during the differentiation of pluripotent ESCs to downstream cells. Conversely, biological rhythms in adult somatic cells disappear when they are reprogrammed into induced pluripotent stem cells (iPSCs). These studies indicated that the development of biological rhythms in ESCs might be closely associated with the maintenance and differentiation of ESCs. The core circadian gene Clock is essential for regulation of biological rhythms. Its role in the development of biological rhythms of ESCs is totally unknown. Here, we used CRISPR/CAS9-mediated genetic editing techniques, to completely knock out the Clock expression in mouse ESCs. By AP, teratoma formation, quantitative real-time PCR and Immunofluorescent staining, we did not find any dif- ference between Clock knockout mESCs and wild type mESCs in morphology and pluripotent capability under the pluripotent state. In brief, these data indicated Clock did not influence the maintaining of pluripotent state. However, they exhibited decreased proliferation and increased apoptosis. Furthermore, the biological rhythms failed to develop in Clock knockout mESCs after spontaneous differentiation, which indicated that there was no compensational factor in most peripheral tissues as described in mice models before (DeBruyne et ah, 2007b). After spontaneous differentiation, loss of CLOCK protein due to Clock gene silencing induced spontaneous differentiation of mESCs, indicating an exit from the pluripotent state, or its differentiating ability. Our findings indicate that the core circadian gene Clock may be essential during normal mESCs differentiation by regulating mESCs proliferation, apoptosis and activity.展开更多
Objective: To investigate the effects of 72 hours continuous sleep deprivation (SD) on circadian clock gene expression and oxidative stress in the rat liver. Methods: Twenty healthy male Sprague-Dawley rats were divid...Objective: To investigate the effects of 72 hours continuous sleep deprivation (SD) on circadian clock gene expression and oxidative stress in the rat liver. Methods: Twenty healthy male Sprague-Dawley rats were divided into 2 groups (n = 10 each) using a random number table: normal control group (group C), sleep deprivation group (group SD). Group SD was treated with a modified multiple platform water environment method. After 72 hours sleep deprived, the levels of AST (Aspartate transaminase ) and ALT (Alanine aminotransferase) in serum were determined. The contents of malondialdehyde (MDA), the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the liver tissue of the rats were examined in both two groups. The expression levels of CLOCK, BMAL1 and CRY1 protein in liver tissue were examined by Western blotting. Results: Compared with group C, the content of MDA, and the levels of AST and ALT in serum were significantly increased (P Conclusion: 72 hours continuous sleep deprivation can downregulate the expression of circadian clock gene and promote oxidative stress in rats.展开更多
Objective: Investigation of the effect of Xiaoaiping on the expression of circadian clock genes in human hepatoma HepG2 cells. Methods: Selecting the HepG2 cells in the logarithmic growth phase and assigning them to...Objective: Investigation of the effect of Xiaoaiping on the expression of circadian clock genes in human hepatoma HepG2 cells. Methods: Selecting the HepG2 cells in the logarithmic growth phase and assigning them to Xiaoaiping injection (XAP) group and control group. The two groups were treated with 75 mg/mL XAP or the same dose of normal saline. After 72 h of treatment, real-time PCR was used to detect the expression of circadian clock genes in HepG2 cells and Western Blot technology was used to detect the expression of related proteins. Results: The mRNA expression levels of PER1, NPAS2, NR1D1, and DEC1 in the XAP group was significantly higher than that in the control group (P〈 0.05), while the mRNA expression levels of PER3, BMAL1, DEC2, and RORA were significantly lower in the XAP group than in the control group (P 〈 0.05), and there was no significant difference between the mRNA expression levels of PER2, CRY1, CRY2, and TIM. Of course, the proteins' expression levels of the genes we had detected such as PERle3, CRYI-2, CLOCK, BMAL1 by Western Blot were consistent with the real-time PCR results above. Conclusion: XAP affects the expression of circadian clock genes in HepG2 cells.展开更多
Colorectal cancer is the most prevalent among digestive system cancers.Carcinogenesis relies on disrupted control of cellular processes,such as metabolism,proliferation,DNA damage recognition and repair,and apoptosis....Colorectal cancer is the most prevalent among digestive system cancers.Carcinogenesis relies on disrupted control of cellular processes,such as metabolism,proliferation,DNA damage recognition and repair,and apoptosis.Cell,tissue,organ and body physiology is characterized by periodic fluctuations driven by biological clocks operating through the clock gene machinery.Dysfunction of molecular clockworks and cellular oscillators is involved in tumorigenesis,and altered expression of clock genes has been found in cancer patients.Epidemiological studies have shown that circadian disruption,that is,alteration of bodily temporal organization,is a cancer risk factor,and an increased incidence of colorectal neoplastic disease is reported in shift workers.In this review we describe the involvement of the circadian clock circuitry in colorectal carcinogenesis and the therapeutic strategies addressing temporal deregulation in colorectal cancer.展开更多
Summary: This study investigated the effects of benazepril administered in the morning or evening on the diurnal variation of renin-angiotensin-aldosterone system (RAAS) and clock genes in the kidney. The male Wist...Summary: This study investigated the effects of benazepril administered in the morning or evening on the diurnal variation of renin-angiotensin-aldosterone system (RAAS) and clock genes in the kidney. The male Wistar rat models of 5/6 subtotal nephrectomy (STNx) were established. Animals were ran- domly divided into 4 groups: sham STNx group (control), STNx group, morning benazepril group (MB) and evening benazepril group (EB). Benazepril was intragastfically administered at a dose of 10 mg/kg/day at 07:00 and 19:00 in the MB group and EB group respectively for 12 weeks. All the animals were synchronized to the light:dark cycle of 12:12 for 12 weeks. Systolic blood pressure (SBP), 24-h urinary protein excretion and renal function were measured at 11 weeks. Blood samples and kidneys were collected every 4 h throughout a day to detect the expression pattern of renin activity (RA), angio- tensin Ⅱ (Ang Ⅱ ) and aldosterone (Aid) by radioimmunoassay (RIA) and the mRNA expression profile of clock genes (bmall, dbp and per2) by real-time PCR at 12 weeks. Our results showed that no signifi- cant differences were noted in the SBP, 24-h urine protein excretion and renal function between the MB and EB groups. There were no significant differences in average Aid and RA content of a day between the MB group and EB group. The expression peak of bmall mRNA was phase-delayed by 4 to 8 h, and the diurnal variation of per2 and dbp mRNA diminished in the MB and EB groups compared with the control and STNx groups. It was concluded when the similar SBP reduction, RAAS inhibition and clock gene profile were achieved with optimal dose of benazepril, morning versus evening dosing of benazepril has the same renoprotection effects.展开更多
文摘Biological rhythms controlled by the circadian clock are absent in embryonic stem cells (ESCs). However, they start to develop during the differentiation of pluripotent ESCs to downstream cells. Conversely, biological rhythms in adult somatic cells disappear when they are reprogrammed into induced pluripotent stem cells (iPSCs). These studies indicated that the development of biological rhythms in ESCs might be closely associated with the maintenance and differentiation of ESCs. The core circadian gene Clock is essential for regulation of biological rhythms. Its role in the development of biological rhythms of ESCs is totally unknown. Here, we used CRISPR/CAS9-mediated genetic editing techniques, to completely knock out the Clock expression in mouse ESCs. By AP, teratoma formation, quantitative real-time PCR and Immunofluorescent staining, we did not find any dif- ference between Clock knockout mESCs and wild type mESCs in morphology and pluripotent capability under the pluripotent state. In brief, these data indicated Clock did not influence the maintaining of pluripotent state. However, they exhibited decreased proliferation and increased apoptosis. Furthermore, the biological rhythms failed to develop in Clock knockout mESCs after spontaneous differentiation, which indicated that there was no compensational factor in most peripheral tissues as described in mice models before (DeBruyne et ah, 2007b). After spontaneous differentiation, loss of CLOCK protein due to Clock gene silencing induced spontaneous differentiation of mESCs, indicating an exit from the pluripotent state, or its differentiating ability. Our findings indicate that the core circadian gene Clock may be essential during normal mESCs differentiation by regulating mESCs proliferation, apoptosis and activity.
文摘Objective: To investigate the effects of 72 hours continuous sleep deprivation (SD) on circadian clock gene expression and oxidative stress in the rat liver. Methods: Twenty healthy male Sprague-Dawley rats were divided into 2 groups (n = 10 each) using a random number table: normal control group (group C), sleep deprivation group (group SD). Group SD was treated with a modified multiple platform water environment method. After 72 hours sleep deprived, the levels of AST (Aspartate transaminase ) and ALT (Alanine aminotransferase) in serum were determined. The contents of malondialdehyde (MDA), the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the liver tissue of the rats were examined in both two groups. The expression levels of CLOCK, BMAL1 and CRY1 protein in liver tissue were examined by Western blotting. Results: Compared with group C, the content of MDA, and the levels of AST and ALT in serum were significantly increased (P Conclusion: 72 hours continuous sleep deprivation can downregulate the expression of circadian clock gene and promote oxidative stress in rats.
文摘Objective: Investigation of the effect of Xiaoaiping on the expression of circadian clock genes in human hepatoma HepG2 cells. Methods: Selecting the HepG2 cells in the logarithmic growth phase and assigning them to Xiaoaiping injection (XAP) group and control group. The two groups were treated with 75 mg/mL XAP or the same dose of normal saline. After 72 h of treatment, real-time PCR was used to detect the expression of circadian clock genes in HepG2 cells and Western Blot technology was used to detect the expression of related proteins. Results: The mRNA expression levels of PER1, NPAS2, NR1D1, and DEC1 in the XAP group was significantly higher than that in the control group (P〈 0.05), while the mRNA expression levels of PER3, BMAL1, DEC2, and RORA were significantly lower in the XAP group than in the control group (P 〈 0.05), and there was no significant difference between the mRNA expression levels of PER2, CRY1, CRY2, and TIM. Of course, the proteins' expression levels of the genes we had detected such as PERle3, CRYI-2, CLOCK, BMAL1 by Western Blot were consistent with the real-time PCR results above. Conclusion: XAP affects the expression of circadian clock genes in HepG2 cells.
基金Supported by The"5x1000"voluntary contribution and by a grant to GM from the Italian Ministry of Health through Department of Medical Sciences,Division of Internal Medicine and Chronobiology Unit,IRCCS Scientific Institute and Regional General Hospital"Casa Sollievo della Sofferenza",Opera di Padre Pio da Pietrelcina,San Giovanni Rotondo(FG),Italy,Nos.RC1203ME46 and RC1302ME31by a grant to AP from the Italian Ministry of Health through Department of Medical Sciences,Division of Gastroenterology and Research Laboratory,Nos.RC1203GA55 and RC1203GA56by a grant to MV from AIRC,No.MFAG-AIRC2012-13419
文摘Colorectal cancer is the most prevalent among digestive system cancers.Carcinogenesis relies on disrupted control of cellular processes,such as metabolism,proliferation,DNA damage recognition and repair,and apoptosis.Cell,tissue,organ and body physiology is characterized by periodic fluctuations driven by biological clocks operating through the clock gene machinery.Dysfunction of molecular clockworks and cellular oscillators is involved in tumorigenesis,and altered expression of clock genes has been found in cancer patients.Epidemiological studies have shown that circadian disruption,that is,alteration of bodily temporal organization,is a cancer risk factor,and an increased incidence of colorectal neoplastic disease is reported in shift workers.In this review we describe the involvement of the circadian clock circuitry in colorectal carcinogenesis and the therapeutic strategies addressing temporal deregulation in colorectal cancer.
基金supported by grants from the Department of Public Health of Hubei Province of China (No. 2012Z-B08)the Health Bureau of Wuhan City of China (No. WX12C10)
文摘Summary: This study investigated the effects of benazepril administered in the morning or evening on the diurnal variation of renin-angiotensin-aldosterone system (RAAS) and clock genes in the kidney. The male Wistar rat models of 5/6 subtotal nephrectomy (STNx) were established. Animals were ran- domly divided into 4 groups: sham STNx group (control), STNx group, morning benazepril group (MB) and evening benazepril group (EB). Benazepril was intragastfically administered at a dose of 10 mg/kg/day at 07:00 and 19:00 in the MB group and EB group respectively for 12 weeks. All the animals were synchronized to the light:dark cycle of 12:12 for 12 weeks. Systolic blood pressure (SBP), 24-h urinary protein excretion and renal function were measured at 11 weeks. Blood samples and kidneys were collected every 4 h throughout a day to detect the expression pattern of renin activity (RA), angio- tensin Ⅱ (Ang Ⅱ ) and aldosterone (Aid) by radioimmunoassay (RIA) and the mRNA expression profile of clock genes (bmall, dbp and per2) by real-time PCR at 12 weeks. Our results showed that no signifi- cant differences were noted in the SBP, 24-h urine protein excretion and renal function between the MB and EB groups. There were no significant differences in average Aid and RA content of a day between the MB group and EB group. The expression peak of bmall mRNA was phase-delayed by 4 to 8 h, and the diurnal variation of per2 and dbp mRNA diminished in the MB and EB groups compared with the control and STNx groups. It was concluded when the similar SBP reduction, RAAS inhibition and clock gene profile were achieved with optimal dose of benazepril, morning versus evening dosing of benazepril has the same renoprotection effects.
基金This work was supported by the National Natural Science Foundation of China(No.30170295),Medical Developmental Foundation of Soochow University(No.EEl 34031) and Young Teacher's Research Foundation of Soochow University(No.Q3134044).
基金This work was supported by the National Natural Science Foundation of China (No.30170295) Medical Developmental Foun- dation of Soochow University (No.EE134031)Young Teacher's Research Foundation of Soochow University (No.Q3134044)