Capsaicin alleviates the hepatic clock gene disruption and gut microbiota dysbiosis in circadian rhythm disorder mouse model

As the body’s internal clock,the circadian rhythm regulates the energy expenditure,appetite,and sleep.There exists a close relationship between the host circadian rhythm and gut microbiota.In this work,a circadian disorder mouse model induced by constant darkness(CD)was constructed to investigate the regulating effects of capsaicin(CAP)on disturbances of metabolism homeostasis and gut microbiota in the respect of circadian rhythm-related mechanisms.Our results indicated that CAP reduced weight gain induced by circadian rhythm disorder in mice by inhibiting fat accumulation in liver and adipose tissue.The rhythmic expressions of circadian clock genes and lipid-metabolism related genes in liver were also recovered by CAP.Microbial study using 16S rRNA sequencing revealed that CAP modulated the gut microbiota richness,diversity and composition,and restored diurnal oscillations of gut microbes at the phylum and family level.These results indicated that CAP could alleviate CD-induced hepatic clock gene disruption and gut microbiota dysbiosis in mice,providing theoretical basis for CAP to be used as a muti-functional ingredient with great healthpromoting effects.

Clock genes:Their role in colorectal cancer

Clock genes create a complicated molecular time-keeping system consisting of multiple positive and negative feedback loops at transcriptional and translational levels. This circadian system coordinates and regulates multiple cellular procedures implicated in cancer development such as metabolism, cell cycle and DNA damage response. Recent data support that molecules such as CLOCK1, BMAL1 and PER and CRY proteins have various effects on c-Myc/p21 and Wnt/β-catenin pathways and influence multiple steps of DNA damage response playing a critical role in the preservation of genomic integrity in normal and cancer cells. Notably, all these events have already been related to the development and progression of colorectal cancer (CRC). Recent data highlight critical correlations between clock genes’ expression and pathogenesis, progression, aggressiveness and prognosis of CRC. Increased expression of positive regulators of this circadian system such as BMAL1 has been related to decrease overall survival while decreased expression of negative regulators such as PER2 and PER3 is connected with poorer differentiation, increased aggressiveness and worse prognosis. The implications of these molecules in DNA repair systems explain their involvement in the development of CRC but at the same time provide us with novel targets for modern therapeutic approaches for patients with advanced CRC.

The Clock gene clone and its circadian rhythms in Pelteobagrus vachelli

The Clock gene,a key molecule in circadian systems,is widely distributed in the animal kingdom. We isolated a 936-bp partial c DNA sequence of the C lock gene( Pva- clock) from the darkbarbel catfish P elteobagrus vachelli that exhibited high identity with C lock genes of other species of fish and animals(65%–88%). The putative domains included a basic helix-loop-helix(b HLH) domain and two period-ARNT-single-minded(PAS) domains,which were also similar to those in other species of fish and animals. P va- Clock was primarily expressed in the brain,and was detected in all of the peripheral tissues sampled. Additionally,the pattern of P va- Clock expression over a 24-h period exhibited a circadian rhythm in the brain,liver and intestine,with the acrophase at zeitgeber time 21:35,23:00,and 23:23,respectively. Our results provide insight into the function of the molecular C lock of P. vachelli.

Effects of Chronotherapy of Benazepril on the Diurnal Profile of RAAS and Clock Genes in the Kidney of 5/6 Nephrectomy Rats

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.

Effect of Xiaoaiping on the expression of circadian clock genes in human hepatoma HepG2 cells

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.

Exploitation of host clock gene machinery by hepatitis viruses B and C

Many aspects of cellular physiology display circadian(approximately 24-h)rhythms.Dysfunction of the circadian clock molecular circuitry is associated with human health derangements,including neurodegeneration,increased risk of cancer,cardiovascular diseases and the metabolic syndrome.Viruses triggering hepatitis depend tightly on the host cell synthesis machinery for their own replication,survival and spreading.Recent evidences support a link between the circadian clock circuitry and viruses’biological cycle within host cells.Currently,in vitro models for chronobiological studies of cells infected with viruses need to be implemented.The establishment of such in vitro models would be helpful to better understand the link between the clock gene machinery and viral replication/viral persistence in order to develop specifically targeted therapeutic regimens.Here we review the recent literature dealing with the interplay between hepatitis B and C viruses and clock genes.

Effects of 72 Hours Sleep Deprivation on Liver Circadian Clock Gene Expression and Oxidative Stress in Rats

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.

The clock gene,period,influences migratory flight and reproduction of the oriental armyworm,Mythimna separata(Walker)

The oriental armyworm,Mythimna separata,is a major long-distance migratory insect pest of grain crops in China and other Asian countries.Migratory flights and reproductive behavior usually occur at night,regulated by a circadian rhythm.However,knowledge about the linkages between adult flight,reproduction,and clock genes is still incomplete.To fill this important gap in our knowledge,a clock gene(designated Msper)was identified and phylogenetic analysis indicated that the encoded protein(MsPER)was highly similar to PER proteins from other insect species.Quantitative RT-PCR assays demonstrated that significantly different spatiotemporal and circadian rhythmic accumulations of mRNA encoding MsPER occurred during development under steady 14 h:10 h light:dark conditions.The highest mRNA accumulation occurred in adult antennae and the lowest in larvae.Msper was expressed rhythmically in adult antennae,relatively less in photophase and more entering scotophase.Injecting small interference RNA(siRNA)into adult heads effectively knocked down Msper mRNA levels within 72 h.Most siRNA-injected adults reduced their evening flight activity significantly and did not exhibit a normal evening peak of flight activity.They also failed to mate and lay eggs within 72 h.Adult mating behavior was restored to control levels by 72 h post injection.We infer that Msper is a prominent clock gene that acts in regulating adult migratory flight and mating behaviors of M.separata.Because of its influence on migration and mating,Msper may be a valuable gene to target for effective management of this migratory insect.

Effects of biological clock gene BMAL1 and hypoxia-inducible factor HIF-1αon proliferation,migration and radiotherapy sensitivity of nasopharyngeal carcinoma cells HONE1

Objective To understand the effects of clock gene BMAL1 and HIF-1α(Hypoxia inducible factor-1α)on proliferation,migration and sensitivity to radiotherapy of nasopharyngeal carcinoma cells HONE1.At the same time,whether the biological clock gene BMAL1 can affect the expression of HIF-1αprotein was investigated.It will lay the foundation for further study on the correlation between clock gene BMAL1 and HIF pathway.Methods BMAL1 gene overexpression and interference lentivirus and HIF-1αgene interference lentivirus were constructed respectively,and were transfected into nasopharyngeal carcinoma cells HONE1.Western blot was used to verify the establishment of overexpressed and knockdown BMAL1 cell lines and HIF-1αgene knockdown cell line,and to investigate the expression of HIF-1αprotein in overexpressed and knockdown BMAL1 cell lines.CCK-8 cell proliferation test and scratch test were used to analyze the proliferation and migration ability of cells.Cell apoptosis after radiotherapy was analyzed by flow cytometry.The effects of BMAL1 and HIF-1αon the sensitivity of HONE1 radiotherapy in nasopharyngeal carcinoma cells after X-ray irradiation at different doses(0Gy,2Gy,4Gy,6Gy)were detected by clone formation assay.Results The overexpression of BMAL1 gene and lentivirus interference were constructed to effectively up regulate and down regulate the expression of BMAL1 protein in nasopharyngeal carcinoma cells HONE1.Meanwhile,HIF-1αgene interference lentivirus was constructed to effectively down-regulate the expression of HIF-1αprotein in nasopharyngeal carcinoma cell line HONE1,and successfully screen out stable nasopharyngeal carcinoma cell lines.Western blot results showed that overexpression of BMAL1 gene could inhibit the expression of HIF-1αprotein in HONE1 of nasopharyngeal carcinoma cells,while knockdown of BMAL1 gene promoted the expression of HIF-1αprotein in HONE1 of nasopharyngeal carcinoma cells(P<0.05).CCK-8 cell proliferation and scratch test showed that overexpression of BMAL1 gene or knockdown of HIF-1αgene could inhibit the proliferation and migration of HONE1 cells(P<0.05).Flow cytometry results showed that after 8Gy irradiation for 72 h,the apoptosis rate of BMALl gene overexpression group was higher than that of the overexpression control group,similarly,the apoptosis rate of HIF-1αgene knockdown group was higher than that of the knockdown control group(P<0.05).After X-ray irradiation at different doses(0Gy,2Gy,4Gy,6Gy),clon-formation experiment showed that the clon-formation rate and cell survival fraction of BMALl overexpression group or HIF-1αknockdown group were lower than those of negative control group(P<0.05).Sigmaplot analysis showed that the D0,Dq and SF2 of the BMAL1 overexpression group or HIF-1αknockdown group were lower than those of the negative control group,and the radiosensitization ratios were 1.381 and 1.063,respectively.Conclusion Overexpression of BMAL1 gene can inhibit the proliferation and migration of nasopharyngeal carcinoma cell line HONE1,increase apoptosis after radiotherapy and improve radiosensitivity.Knock down HIF-1αGene can inhibit the proliferation and migration of nasopharyngeal carcinoma cell line HONE1,increase apoptosis after radiotherapy and improve radiosensitivity.In nasopharyngeal carcinoma cells HONE1,overexpression of BMAL1 gene can inhibit the expression of HIF-1αprotein while knockdown of BMAL1 gene can promote the expression of HIF-1αprotein.

亲子关系与CLOCK基因rs1801260多态性对学前儿童亲社会行为的交互影响:性别的调节作用

研究探讨了亲子关系与CLOCK基因rs1801260多态性对学前儿童亲社会行为的交互影响及性别的调节作用。以694名学前儿童(M_(年龄)=5.06岁,SD=0.87)及其父母为测试对象,收集儿童的唾液样本进行基因分型,由儿童父母填写亲子关系和儿童亲社会行为量表。研究结果发现,亲子亲密与亲子冲突对亲社会行为的主效应显著。亲子冲突、CLOCK基因rs1801260多态性和性别三重交互影响儿童的亲社会行为,即与携带C等位基因的男孩相比,携带TT基因型的男孩在低亲子冲突下会表现出更多的亲社会行为,在高亲子冲突下则表现出更少的亲社会行为。但亲子冲突与CLOCK基因rs1801260多态性对女孩亲社会行为的交互作用不显著。研究结果为深入理解学前儿童亲社会行为形成的基因-环境交互作用机制提供了证据。

Co-regulation of circadian clock genes and microRNAs in bone metabolism

Mammalian bone is constantly metabolized from the embryonic stage,and the maintenance of bone health depends on the dynamic balance between bone resorption and bone formation,mediated by osteoclasts and osteoblasts.It is widely recognized that circadian clock genes can regulate bone metabolism.In recent years,the regulation of bone metabolism by non-coding RNAs has become a hotspot of research.MicroRNAs can participate in bone catabolism and anabolism by targeting key factors related to bone metabolism,including circadian clock genes.However,research in this field has been conducted only in recent years and the mechanisms involved are not yet well established.Recent studies have focused on how to target circadian clock genes to treat some diseases,such as autoimmune diseases,but few have focused on the co-regulation of circadian clock genes and microRNAs in bone metabolic diseases.Therefore,in this paper we review the progress of research on the co-regulation of bone metabolism by circadian clock genes and microRNAs,aiming to provide new ideas for the prevention and treatment of bone metabolic diseases such as osteoporosis.

大负荷运动后骨骼肌核心时钟基因Bmal1/Clock、Cry1/Per1的节律性振荡变化趋势

目的:探讨大负荷运动对骨骼肌核心时钟基因节律性表达的影响。方法:将208只8周龄SD大鼠随机分为对照(control,C)组与运动(Exercise,E)组,E组予以一次大负荷运动训练。每6 h取各组比目鱼肌,采用透射电镜观察骨骼肌纤维超微结构,通过实时荧光定量PCR实验测定骨骼肌核心时钟基因Bmal1、Clock、Cry1、Per1表达量,并使用余弦分析软件circacompare(R package)获取拟合余弦曲线参数,分析其节律性振荡的变化趋势。结果:1)C组Bmal1、Clock、Cry1、Per1 mRNA在72 h内呈现3个完整近日节律周期;E组Bmal1 mRNA、Cry1和Per1mRNA在0~24 h、Clock mRNA在0~72 h近日节律消失。2)与C组相比,E组Bmal1 mRNA在0、6、12和18 h显著升高,Clock mRNA在0 h时显著升高;Cry1、Per1 mRNA在0、12 h显著降低。3)C组各时相肌纤维超微结构正常,E组0、24和48 h均出现不同程度肌小节结构破坏、线粒体肿胀及聚集等改变,72 h有所缓解。结论:一次大负荷运动可诱发骨骼肌核心时钟基因Bmal1/Clock、Cry1/Per1节律振荡紊乱,其变化趋势与肌纤维超微结构损伤时相基本一致。

电针对昼夜节律紊乱C57BL/6J小鼠肝脏基因Clock、Bmal1表达的影响

目的 观察电针肝俞对昼夜节律紊乱小鼠外周时钟基因的影响,分析各实验条件下,不同时间点Clock、Bmal1基因的分布规律,为外周生物钟基因时间分布提供参考,并探讨电针治疗睡眠节律紊乱的潜在机制。方法 将72只C57BL/6J小鼠按随机数字表法分成空白组、模型组、肝俞组和非经非穴组,每组18只。空白组常规饲养;其余3组采取光暗交替法L(光)∶D(暗)=2 h∶2 h造模法持续5 d,模型组只捆绑不针刺;肝俞组针刺肝俞穴;非经非穴组选取非经非穴部位进行针刺。电针干预5 d后,于第6天02∶00开始,每组每4 h取材1次,共取材6次。采用PCR法以及Western blot法检测各组小鼠肝脏内的Clock和Bmal1基因mRNA的表达水平和蛋白表达含量,同时用余弦函数计算出各组基因的节律性。结果 与模型组比较,肝俞组中Clock与Bmal1基因表达恢复时间节律(P<0.05)。与模型组比较,非经非穴组内Clock与Bmal1基因表达无时序性(P>0.05);肝俞组Clock、Bmal1的蛋白表达量较模型组明显降低且恢复节律性(P<0.05)。结论 小鼠肝脏中Clock和Bmal1时钟基因呈时序性变化,电针肝俞穴可改善小鼠睡眠,其机制可能与调节时钟基因Clock和Bmal1,降低两种基因及蛋白表达,恢复正常睡眠节律有关。

生物钟相关基因CLOCK及褪黑素受体MT1和MT2基因与2型糖尿病患者肠道菌群及炎症因子相关性分析

目的:探讨生物钟基因CLOCK及褪黑素受体MT1和MT2基因与2型糖尿病(T2DM)患者肠道菌群及炎症因子的相关性。方法:选择T2DM患者80例为观察组,选择同期进行健康体检者80例为对照组。检测两组血清CLOCK、MT1和MT2基因水平,以及超敏C反应蛋白(hs-CRP)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)和IL-18水平。检测两组粪便中肠杆菌、双歧杆菌、乳杆菌、肠球菌、双歧杆菌/肠杆菌丰度。分析观察组血清CLOCK、MT1和MT2基因水平与T2DM患者肠道菌群及炎症因子的相关性。结果:观察组血清CLOCK、MT1、MT2基因水平明显较对照组低(均P<0.05)。观察组肠杆菌水平明显较对照组高,双歧杆菌、乳杆菌、双歧杆菌/肠杆菌水平明显较对照组低(均P<0.05)。观察组hs-CRP、IL-6、TNF-α、IL-18水平明显较对照组高(均P<0.05)。观察组血清CLOCK、MT1、MT2基因水平与肠杆菌、hs-CRP、IL-6、TNF-α、IL-18水平呈负相关,与双歧杆菌、乳杆菌、双歧杆菌/肠杆菌水平呈正相关(均P<0.05)。结论:血清生物钟相关基因CLOCK、MT1和MT2基因与T2DM患者肠道菌群及炎症因子均有一定相关性,可作为潜在的诊断指标及治疗靶点。

异齿裂腹鱼Clock基因cDNA的克隆与组织表达特征

异齿裂腹鱼广布于雅鲁藏布江,产卵期为每年的3—5月,表现出明显的季节性繁殖行为,Clock基因被认为是自然选择塑造日节律以及与动物繁殖等生活史特性有关潜在的目标基因,异齿裂腹鱼Clock蛋白C末端Poly-Q长度的变异可能与其产卵开始的时间关联。以采自雅鲁藏布江的异齿裂腹鱼为对象,采用反转录PCR和cDNA末端快速扩增技术克隆异齿裂腹鱼Clock基因cDNA全长序列,通过实时荧光定量PCR对其在异齿裂腹鱼雌、雄个体不同组织中的表达特征进行分析。试验结果显示:异齿裂腹鱼Clock基因cDNA全长为4291 bp(Genbank登录号MT774361),5′非编码区为539 bp,3′非编码区为1046 bp,编码序列为2706 bp,共编码901个氨基酸,所编码的氨基酸在末端具有典型的Poly-Q结构;Clock基因在异齿裂腹鱼雌、雄个体的肝脏、脾脏、心脏、脑、性腺和肌肉中均有表达,且以性腺中的相对表达量最高,肌肉次之,脾脏最低;Clock基因除在心脏组织中的相对表达量雄鱼高于雌鱼,在其他组织的相对表达量均表现为雌鱼高于雄鱼。异齿裂腹鱼雌、雄个体的Clock基因在性腺组织中均高表达,表明Clock基因在异齿裂腹鱼的繁殖过程中发挥着更大的作用,异齿裂腹鱼Clock蛋白大片段的插入也可能是为了适应高海拔某些条件而特化的。

Circadian Clock Genes Universally Control Key Agricultural Traits

Circadian clocks are endogenous timers that enable plants to synchronize biological processes with daily and seasonal environmental conditions in order to allocate resources during the most beneficial times of day and year. The circadian clock regulates a number of central plant activities, including growth, develop- ment, and reproduction, primarily through controlling a substantial proportion of transcriptional activity and protein function. This review examines the roles that alleles of circadian clock genes have played in domestication and improvement of crop plants. The focus here is on three groups of circadian clock genes essential to clock function in Arabidopsis thaliana： PSEUDO-RESPONSE REGULATORs, GIGANTEA, and the evening complex genes EARL Y FLOWERING 3, EARLY FLOWERING 4, and LUX ARRHYTHMO. Homol- ogous genes from each group underlie quantitative trait loci that have beneficial influences on key agricul- tural traits, especially flowering time but also yield, biomass, and biennial growth habit. Emerging insights into circadian clock regulation of other fundamental plant processes, including responses to abiotic and biotic stresses, are discussed to highlight promising avenues for further crop improvement.

柴胡皂苷A调节cAMP/PKA/CREB信号通路对失眠大鼠的改善作用及机制研究

目的基于cAMP/PKA/CREB通路探讨柴胡皂苷A对失眠大鼠的改善作用及机制。方法将75只SD大鼠随机分为空白组、模型组、柴胡皂苷A低剂量组(0.625 mg·kg^(-1))、柴胡皂苷A高剂量组(2.500 mg·kg^(-1))、艾司唑仑组(0.1 mg·kg^(-1)),每组15只。采用腹腔注射苯丙氨酸(PCPA,0.1 mg·kg^(-1))复制失眠大鼠模型。观察大鼠一般情况及昼夜节律;采用戊巴比妥钠翻正实验测定大鼠睡眠潜伏期及睡眠持续时间;观测大鼠睡眠时相,记录慢波睡眠第1期(SWS1)、慢波睡眠第2期(SWS2)、快速眼球运动睡眠期(REMS)时长以及总睡眠时长(TST);qRT-PCR法测定下丘脑节律基因Clock、Bmal1 mRNA及钟控基因Rev-erbα、RorαmRNA的表达水平;免疫荧光法测定海马组织NeuN表达水平;ELISA法测定脑组织中的cAMP水平;Western Blot法测定脑组织中Clock、Bmal1、Rev-erbα、Rorα及cAMP/PKA/CREB通路相关蛋白表达水平。结果与空白组比较,模型组大鼠昼伏夜出的节律紊乱,极度兴奋,易激惹,睡眠减少;睡眠潜伏期明显延长(P<0.05),睡眠持续时间及SWS1、SWS2、REMS、TST均明显缩短(P<0.05);神经元排列紊乱,NeuN阳性神经元IOD值明显降低(P<0.05);脑组织Clock、Bmal1、Rev-erbα、RorαmRNA及蛋白表达水平明显降低(P<0.05);脑组织cAMP、p-PKA/PKA、p-CREB/CREB蛋白表达水平明显降低(P<0.05)。与模型组比较,给药组大鼠的攻击性明显减弱,昼伏夜出有节律性,活动减少,睡眠增多;睡眠潜伏期明显缩短(P<0.05),睡眠持续时间及SWS1、SWS2、REMS、TST均明显延长(P<0.05);神经元排列紊乱情况有所恢复,NeuN阳性神经元IOD值明显升高(P<0.05);脑组织Clock、Bmal1、Rev-erbα、RorαmRNA及蛋白表达水平明显升高(P<0.05);脑组织cAMP、p-PKA/PKA、p-CREB/CREB蛋白表达水平明显升高(P<0.05)。结论柴胡皂苷A可能通过激活cAMP/PKA/CREB通路改善失眠大鼠的昼夜节律。

Knockdown the Circadian Clock Gene period and timeless arrest the Photoperiodic Induction of Summer Diapause in Colaphellus bowringi Baly

In insects,facultative diapause is a state of developmental arrest mainly induced by photoperiod or temperature that allows insects to survive adverse environmental conditions.Understanding how insect initiates facultative diapause and prepares diapause can provide us new insights to study developmental and evolutionary biology.It has been shown that the circadian clock genes can participate in photoperiodic measurement and regulate reproductive diapause initiation through JH signaling in short-day-induced winter diapause.However,how circadian clock genes translate photoperiodic information into downstream JH signaling for diapause destiny and then affect diapause preparation remains largely unknown.In the present study,we investigate this in the cabbage beetle Colaphellus bowringi which undergoes reproductive diapause under long-day condition.We respectively knocked down two circadian clock negative regulators,period(per)and timeless(tim),in the 3-day-old larvae(most sensitive to photoperiod),and dsgfp treatment was served as a control.Under the diapause-inducing photoperiod(16L:8D),knocking down per and tim significantly decreased the rate of burrowing behavior.And mtany female beetles of the per and tim RNAi showed developed ovary,decreased lipid accumulation and downregulated expression of stress resistance genes.The JHinduced genes,Kr-h1,JHE1,Vg1,and Vg2, significantly increased in the females with suppression of per and tim.It implied that suppression of per and tim during diapause initiation phase(DIP)could activate the JH signaling in the female adults.Before the beetles enter into diapause preparation phase(DPP),we used RNA sequencing to analyize gene expression profiles after per and tim RNAi.It showed that many differentially expressed genes were enriched in environmental information processing,such as mTOR and TGF-beta signaling pathway.To ask whether per and tim also regulate diapause preparation,we knocked down these two genes in the female adults during DPP.It showed that the diapause destiny was not af-fected,but the lipid storage in diapause-destined females was significantly reduced after per and tim RNAi.Interestingly,per-and tim-regulated lipid storage during DPP was independent on JH signaling.We further found that per and tim promoted lipid storage by regulating the expression of genes that control lipogenesis and lipolysis.In summary,these results suggest that per and tim participate in photoperiodic measurement and initiate reproductive diapause through JH signaling during DIP in long-day-induced summer diapause.The mTOR and TGF-beta signaling pathways may be involved in the regulation of JH signaling by circadian clock genes.Meanwhile,per and tim transduce photoperiodic signal and promote lipid storage during DPP in a JH-independent manner.These results provide us new clues to study the molecular mechanism of photoperiod-regulated diapause induction in insects.

生物节律与子痫前期的相关性

子痫前期(preeclampsia,PE)是一种常见的妊娠并发症,危害母婴健康,更是一个严重的国际公共卫生问题。尽管已证实PE的高危因素包括肥胖、糖尿病和妊娠前高血压等,但其发病机制仍未完全阐明。哺乳动物中绝大多数的生理过程由生物节律调控,生物节律的破坏被证实与众多疾病相关,如心血管疾病、糖尿病和乳腺癌等。尽管PE具有一系列时间生物节律的特征性表现,如PE患者的血压24 h节律变异性、“反勺状”血压与更严重的靶器官损伤有关、夜间服用阿司匹林的预防保护作用更优异等,但生物节律的变异是否为PE的危险因素,抑或PE本身是否与异常的生物节律相关,目前尚未明确。综述生物节律与PE的相关性,包括胎盘的钟基因表达及其与PE的关系、血压的生物节律、PE预防的时间治疗学、生物节律的破坏与PE风险性,以启示今后深入研究生物节律/钟基因与PE之间潜在关联的必要性。

辛伐他汀预防小鼠高脂血症合并脑缺血损伤及其对时钟基因的调控

目的探讨辛伐他汀对小鼠高血脂合并脑缺血再灌注损伤(CIRI)的预防作用及机制。方法将60只C57BL/6J小鼠分为假手术组、CIRI组〔采用大脑中动脉阻塞再灌注法(MCAO/R)制备小鼠CIRI模型〕、高脂组(ip给予泊洛沙姆407)、高脂+CIRI组(ip给予泊洛沙姆407,24 h后MCAO/R造模)、高脂+CIRI+辛伐他汀5和10 mg·kg^(-1)组(先ig给予辛伐他汀连续7 d,后按照高脂+CIRI组处理)。再灌注24 h后,对各组小鼠进行神经功能缺损评分;转棒实验测定掉落潜伏期;自主活动测试小鼠活动次数;TTC染色测定脑梗死体积;激光散斑血流成像检测小鼠脑血流量;取全血分离血清,并测定总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、丙二醛(MDA)和谷胱甘肽过氧化物酶(GSH-PX)含量;实时荧光定量PCR和Westen印迹法检测小鼠右脑皮质时钟基因Rev-erbα和Bmal1 mRNA及蛋白表达水平。结果与假手术组相比,CIRI组小鼠神经功能缺损评分升高(P<0.01),掉落潜伏期缩短(P<0.01),活动次数减少(P<0.01)。与CIRI组相比,高脂+CIRI组小鼠神经功能损伤加重(P<0.01);脑梗死体积显著增加(P<0.01);脑血流量显著降低(P<0.01);血清中TC,TG,LDL-C及MDA含量显著升高(P<0.01),GSH-PX水平显著降低(P<0.01);脑皮质Rev-erbαmRNA和蛋白表达水平显著下调(P<0.01);Bmal1 mRNA和蛋白表达水平显著上调(P<0.01)。与高脂+CIRI组相比,高脂+CIRI+辛伐他汀5和10 mg·kg^(-1)组小鼠神经功能损伤减轻(P<0.01);脑梗死体积显著减小(P<0.01);脑血流量显著增加(P<0.01);血清中TC,TG,LDL-C及MDA含量显著降低(P<0.01),GSH-PX水平显著升高(P<0.01);脑皮质Rev-erbαmRNA和蛋白表达水平显著上调(P<0.01);Bmal1 mRNA和蛋白表达水平显著下调(P<0.01)。结论辛伐他汀预防性给药能有效减轻小鼠高脂血症合并CIRI,其机制与其降血脂及调节时钟基因表达有关。