Circadian Influence on Metabolism and Inflammation in Atherosclerosis

Uncovering the Penile Clock: Expression of Molecular Clock Proteins in Human Penile Cavernous Tissue

PURPOSE

To evaluate the expression of core molecular clock genes/proteins in penile cavernous tissue from healthy male subjects and to determine whether their expression has circadian variation.

MATERIALS AND METHODS

Corpus cavernosum biopsy samples were obtained from 10 healthy males with penile deviation or fracture who underwent surgical intervention during the day and night. The daytime group (n=5) underwent corpus cavernosum tissue sampling during zeitgeber time (ZT) 8-12, while the nighttime group (n=5) underwent sampling during ZT 20-24. The expression and localization of BMAL1, CLOCK, PER1, PER2, PER3, CRY1, and CRY2 proteins were analyzed using immunohistochemistry and quantified using H-score analysis. RT-qPCR analysis was performed to assess the expression of core molecular clock genes in the corpus cavernosum tissue of 5 additional daytime patients.

RESULTS

The expression of core molecular clock proteins was detected in vascular endothelial cells (VECs) and smooth muscle cells (SMCs) in corpus cavernosum during daytime and nighttime. BMAL1 exhibited the most significant nuclear expression during daytime in both cell types, whereas its expression decreased significantly at night. In VECs, a significant decrease in the nuclear expression of CRY1 was observed at night. In SMCs, a significant decrease in the cytoplasmic expression of PER3 was observed at night. The expression patterns of the core molecular clock genes were ascertained through a RT-qPCR analysis.

CONCLUSIONS

Our research provides compelling evidence that core molecular clock genes are distinctly expressed in penile tissue in humans. Furthermore, we observed the expression of molecular clock proteins within the VECs and SMCs of the corpus cavernosum, with BMAL1 being the most prominently expressed. The discovery of core molecular clock genes in penile tissue, as well as proteins within the SMCs and VECs of the corpus cavernosum, introduces the potential significance of the molecular clock mechanism in the physiology of penile erection.

Circadian gene CLOCK accelerates atherosclerosis by promoting endothelial autophagy

Atherosclerosis (AS) is a chronic inflammatory disease which gives rise to life-threatening complications like ischemic stroke. Rupture of carotid atherosclerotic plaque is the main cause of ischemic stroke. Emerging evidence has demonstrated that disturbed circadian rhythms could accelerate the progression of atherosclerosis by regulating endothelial function. Moreover, our previous study implicated the circadian gene circadian locomotor output cycles kaput (CLOCK) in the pathogenesis of unstable plaques. In this study, we explored the underlying mechanism that CLOCK mediates endothelial cell autophagy involved in the progression of AS. Circadian and autophagy gene expression was analyzed in the GSE41571 dataset and human carotid atherosclerotic plaque samples. Then we used ox-LDL to treat HUVECs, and analyzed CLOCK and autophagy gene in endothelial cells. Besides that, we comprehensively analyzed in vivo experiments to explore the function of CLOCK in autophagy and atherosclerosis using different staining including HE, MT and IF staining. In the dataset and patient samples, CLOCK expression and autophagy were decreased in the unstable plaque group compared with the stable group. Decreased Beclin1, ATG5, LC3, and CLOCK were also observed in HUVECs under oxidative stress condition which also enhances cell proliferation. In vivo, we also found decreasing level of CLOCK, Beclin1, LC3 and ATG5 in ApoE-/- mice compared with WT mice. Silencing of CLOCK in ApoE-/- mice may further aggravate atherosclerosis including decreased cap thickness and collagens. Our findings implicated that downregulation CLOCK would impair endothelial cell autophagy and accelerate atherosclerotic plaque, which provides a novel strategy for treatment of progression in AS.

Equisetin protects from atherosclerosis in vivo by binding to STAT3 and inhibiting its activity

Atherosclerosis is a chronic inflammatory vascular disease characterized by lipid metabolism disorder and lipid accumulation. Equisetin (EQST) is a hemiterpene compound isolated from fungus of marine sponge origin, which has antibacterial, anti-inflammatory, lipid-lowering, and weight loss effects. Whether EQST has anti-atherosclerotic activity has not been reported. In this study, we revealed that EQST displayed anti- atherosclerosis effects through inhibiting macrophage inflammatory response, lipid uptake and foam cell formation in vitro, and finally ameliorated high-fat diet (HFD)-induced atherosclerosis in AopE-/- mice in vivo. Mechanistically, EQST directly bound to STAT3 with high-affinity by forming hydrophobic bonds at GLN247 and GLN326 residues, as well as hydrogen bonds at ARG325 and THR346 residues. EQST interacted with STAT3 physically, and functionally inhibited the transcription activity of STAT3, thereby regulating atherosclerosis. Therefore, these results supports EQST as a candidate for developing anti-atherosclerosis therapeutic agent.

Sleep duration irregularity and risk for incident cardiovascular disease in the UK Biobank

Background

Emerging evidence supports a link between circadian disruption as measured by higher night-to-night variation in sleep duration and increased risk of cardiovascular disease (CVD). It remains unclear whether this association varies by CVD types or may be modified by average sleep duration and genetic risk for CVD.

Methods

Our prospective analysis included 86,219 UK Biobank participants who were free from CVD when completing 7 days of accelerometer measurement in 2013-2016. Sleep irregularity was evaluated by the standard deviation (SD) of accelerometer-measured sleep duration over 7 days. Incident major CVD events, defined as fatal or nonfatal myocardial infarction (MI) and stroke, were identified through linkage to Hospital Episode Statistics data until May 31, 2022. Multivariable-adjusted Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% CIs for associations of sleep duration SD with risk for major CVD events overall and for MI and stroke separately.

Results

We documented 2,310 incident cases of major CVD events (MI: 1,183, stroke: 1,175) over 636,258 person-years of follow-up. After adjusting for sociodemographic factors and family history of CVD, the HR (95% CI) associated with a 1-hour increase in sleep duration SD was 1.19 (1.10, 1.27) for CVD (p-trend<0.0001), 1.23 (1.11, 1.35) for MI (p-trend<0.0001), and 1.17 (1.05, 1.29) for stroke (p-trend=0.003). Additional adjustment for lifestyle factors, co-morbidities and sleep-related factors modestly attenuated these associations. Higher sleep irregularity was associated with higher CVD risk irrespective of genetic risk (p-interaction=0.43), but this association was stronger among individuals with longer average sleep duration >8 hours (p-interaction=0.006).

Conclusions

Higher night-to-night variation in accelerometer-measured sleep duration was associated with consistently higher risks for major CVD events. The association did not seem to be modified by genetic risk for CVD and was more pronounced in long sleepers.

The association between time-restricted eating and arterial stiffness status in community-dwelling elderly Chinese individuals

BACKGROUND AND AIMS

Emerging studies indicate that time-restricted eating (TRE) may protect against cardiovascular disease (CVD); however, studies performed in elderly adults are limited. This study aimed to analyze the association of TRE with arterial stiffness (AS) in community-dwelling elderly Chinese individuals.

METHODS AND RESULTS

This cross-sectional study recruited 3487 participants aged ≥60 y from Shanghai, China. TRE was determined by calculating the end time of the last meal minus the start time of the first meal of the average day. Participants were then categorized into those with a time-restricted window lasting ≤11 h (TRE) and >11 h (non-TRE). The mean age of the sample was 71.78 ± 5.75 y, and 41.2 % were men. Having a TRE pattern was 72.2 %. In the logistic analysis, TRE was associated with borderline arterial stiffness (OR = 1.419; 95 % CI = 1.077-1.869) and elevated arterial stiffness (OR = 1.699; 95 % CI = 1.276-2.263). In a subgroup analysis, the significance remained in the group at risk of malnutrition (with borderline arterial stiffness: OR = 2.270; 95 % CI = 1.229-4.190; with elevated arterial stiffness: OR = 2.459; 95 % CI = 1.287-4.700), while in well-nourished participants, the association only remained with elevated arterial stiffness (OR = 1.530; 95 % CI = 1.107-2.115) and not with borderline arterial stiffness.

CONCLUSIONS

TRE is a risk factor for both borderline and elevated arterial stiffness in community-dwelling Chinese individuals and varies by nutritional status. (Protocol code 2019-WJWXM-04-310108196508064467.).

A review for the impacts of circadian disturbance on urological cancers

Circadian rhythm is an internal timing system and harmonizes a variety of cellular, behavioral, and physiological processes to daily environment. Circadian disturbance caused by altered life style or disrupted sleep patterns inevitably contributes to various disorders. As the rapidly increased cancer occurrences and subsequent tremendous financial burdens, more researches focus on reducing the morbidity rather than treating it. Recently, many epidemiologic studies demonstrated that circadian disturbance was tightly related to the occurrence and development of cancers. For urinary system, numerous clinical researches observed the incidence and progress of prostate cancer were influenced by nightshift work, sleep duration, chronotypes, light exposure, and meal timing, this was also proved by many genetic and fundamental findings. Although the epidemiological studies regarding the relationship between circadian disturbance and kidney/bladder cancers were relative limited, some basic researches still claimed circadian disruption was closely correlated to these two cancers. The role of circadian chemotherapy on cancers of prostate, kidney, and bladder were also explored, however, it has not been regularly recommended considering the limited evidence and poor standard protocols. Finally, the researches for the impacts of circadian disturbance on cancers of adrenal gland, penis, testis were not found at present. In general, a better understanding the relationship between circadian disturbance and urological cancers might help to provide more scientific work schedules and rational lifestyles which finally saving health resource by reducing urological tumorigenesis, however, the underlying mechanisms are complex which need further exploration.

Circadian disturbance induces erectile dysfunction by impairing endothelial function

In order to explore the impact of circadian disturbance on erectile function, we randomly divided 24 adult male rats into groups of control (light on at 8:00 a.m. and off at 8:00 p.m.), dark/dark (DD; constant dark), light/light (LL; constant light), and shift dark/light (DL; light off at 8:00 a.m. and on at 8:00 p.m.). Four weeks later, erectile function was measured and corpora cavernosa were harvested for analysis. The maximum intracavernous pressure (mICP) and mICP/mean arterial pressure (MAP) ratio in the DD, LL, and DL groups were significantly lower than that in the control group. The LL and DL groups showed significantly attenuated endothelial nitric oxide synthase (eNOS), while DD, LL, and DL showed reduced neuronal nitric oxide synthase (nNOS) at both mRNA and protein levels. The production of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) was inhibited by altered light/dark cycles to varying degrees. Circadian disturbance impaired endothelial function and contributed to erectile dysfunction. For the core circadian elements, mRNA expression of circadian locomotor output cycles kaput ( Clock ) and brain/muscle aryl-hydrocarbon receptor nuclear translocator-like protein 1 ( Bmal1 ) was elevated in the DL group, but their protein expression was not significantly changed. DD, LL, and DL increased period 1 ( Per1 ) and Per3 levels, while LL and DL increased PER1 levels. No significant difference was found for Per2 levels, and PER2 and PER3 concentrations were not significantly changed. Moreover, LL and DL significantly increased cryptochrome-1 (CRY1) and CRY2 at both mRNA and protein levels. The altered light/dark rat model showed that circadian disturbance contributed to erectile dysfunction probably by impairing endothelial function. Meanwhile, the core circadian elements were detected in the corpora cavernosa, but these were disrupted. However, which circadian element regulates erectile function and how it works need further analysis.

Sleep and circadian rhythm disturbance in kidney stone disease: a narrative review

The circadian rhythm generated by circadian clock genes functions as an internal timing system. Since the circadian rhythm controls abundant physiological processes, the circadian rhythm evolved in organisms is salient for adaptation to environmental change. A disturbed circadian rhythm is a trigger for numerous pathological events. Recently, accumulated data have indicated that kidney stone disease (KSD) is related to circadian rhythm disturbance. However, the mechanism between them has not been fully elucidated. In this narrative review, we summarized existing evidence to illustrate the possible association between circadian rhythm disturbance and KSD based on the epidemiological studies and risk factors that are linked to circadian rhythm disturbance and discuss some chronotherapies for KSD. In summary, KSD is associated with systemic disorders. Metabolic syndrome, inflammatory bowel disease, and microbiome dysbiosis are the major risk factors supported by sufficient data to cause KSD in patients with circadian rhythm disturbance, while others including hypertension, vitamin D deficiency, parathyroid gland dysfunction, and renal tubular damage/dysfunction need further investigation. Then, some chronotherapies for KSD were confirmed to be effective, but the molecular mechanism is still unclear.

The Role of the Circadian Rhythm in Dyslipidaemia and Vascular Inflammation Leading to Atherosclerosis

Cardiovascular diseases (CVD) are among the leading causes of death worldwide. Many lines of evidence suggest that the disturbances in circadian rhythm are responsible for the development of CVDs; however, circadian misalignment is not yet a treatable trait in clinical practice. The circadian rhythm is controlled by the central clock located in the suprachiasmatic nucleus and clock genes (molecular clock) located in all cells. Dyslipidaemia and vascular inflammation are two hallmarks of atherosclerosis and numerous experimental studies conclude that they are under direct influence by both central and molecular clocks. This review will summarise the results of experimental studies on lipid metabolism, vascular inflammation and circadian rhythm, and translate them into the pathophysiology of atherosclerosis and cardiovascular disease. We discuss the effect of time-respected administration of medications in cardiovascular medicine. We review the evidence on the effect of bright light and melatonin on cardiovascular health, lipid metabolism and vascular inflammation. Finally, we suggest an agenda for future research and recommend on clinical practice.

Disturbance of suprachiasmatic nucleus function improves cardiac repair after myocardial infarction by IGF2-mediated macrophage transition

Suprachiasmatic nucleus (SCN) in mammals functions as the master circadian pacemaker that coordinates temporal organization of physiological processes with the environmental light/dark cycles. But the causative links between SCN and cardiovascular diseases, specifically the reparative responses after myocardial infarction (MI), remain largely unknown. In this study we disrupted mouse SCN function to investigate the role of SCN in cardiac dysfunction post-MI. Bilateral ablation of the SCN (SCNx) was generated in mice by electrical lesion; myocardial infarction was induced via ligation of the mid-left anterior descending artery (LAD); cardiac function was assessed using echocardiography. We showed that SCN ablation significantly alleviated MI-induced cardiac dysfunction and cardiac fibrosis, and promoted angiogenesis. RNA sequencing revealed differentially expressed genes in the heart of SCNx mice from D0 to D3 post-MI, which were functionally associated with the inflammatory response and cytokine-cytokine receptor interaction. Notably, the expression levels of insulin-like growth factor 2 (Igf2) in the heart and serum IGF2 concentration were significantly elevated in SCNx mice on D3 post-MI. Stimulation of murine peritoneal macrophages in vitro with serum isolated from SCNx mice on D3 post-MI accelerated the transition of anti-inflammatory macrophages, while antibody-mediated neutralization of IGF2 receptor blocked the macrophage transition toward the anti-inflammatory phenotype in vitro as well as the corresponding cardioprotective effects observed in SCNx mice post-MI. In addition, disruption of mouse SCN function by exposure to a desynchronizing condition (constant light) caused similar protective effects accompanied by elevated IGF2 expression on D3 post-MI. Finally, mice deficient in the circadian core clock genes (Ckm-cre; Bmal1f/f mice or Per1/2 double knockout) did not lead to increased serum IGF2 concentration and showed no protective roles in post-MI, suggesting that the cardioprotective effect observed in this study was mediated particularly by the SCN itself, but not by self-sustained molecular clock. Together, we demonstrate that inhibition of SCN function promotes Igf2 expression, which leads to macrophage transition and improves cardiac repair post-MI.

Circadian rhythm in cardiovascular diseases: a bibliometric analysis of the past, present, and future

BACKGROUND

One of the most prominent features of living organisms is their circadian rhythm, which governs a wide range of physiological processes and plays a critical role in maintaining optimal health and function in response to daily environmental changes. This work applied bibliometric analysis to explore quantitative and qualitative trends in circadian rhythm in cardiovascular diseases (CVD). It also aims to identify research hotspots and provide fresh suggestions for future research.

METHODS

The Web of Science Core Collection was used to search the data on circadian rhythm in CVD. HistCite, CiteSpace, and VOSviewer were used for bibliometric analysis and visualization. The analysis included the overall distribution of yearly outputs, top nations, active institutions and authors, core journals, co-cited references, and keywords. To assess the quality and efficacy of publications, the total global citation score (TGCS) and total local citation score (TLCS) were calculated.

RESULTS

There were 2102 papers found to be associated with the circadian rhythm in CVD, with the overall number of publications increasing year after year. The United States had the most research citations and was the most prolific country. Hermida RC, Young ME, and Ayala DE were the top three writers. The three most notable journals on the subject were Chronobiology International, Hypertension Research, and Hypertension. In the early years, the major emphasis of circadian rhythm in CVD was hormones. Inflammation, atherosclerosis, and myocardial infarction were the top developing research hotspots.

CONCLUSION

Circadian rhythm in CVD has recently received a lot of interest from the medical field. These topics, namely inflammation, atherosclerosis, and myocardial infarction, are critical areas of investigation for understanding the role of circadian rhythm in CVD. Although they may not be future research priorities, they remain of significant importance. In addition, how to implement these chronotherapy theories in clinical practice will depend on additional clinical trials to get sufficient trustworthy clinical evidence.

BMAL1 Promotes Valvular Interstitial Cells’ Osteogenic Differentiation through NF-κ B/AKT/MAPK Pathway

Objectives: Calcific aortic valve disease (CAVD) is most common in the aging population and is without effective medical treatments. Brain and muscle ARNT-like 1 (BMAL1) is related to calcification. It has unique tissue-specific characteristics and plays different roles in different tissues’ calcification processes. The purpose of the present study is to explore the role of BMAL1 in CAVD. Methods: The protein levels of BMAL1 in normal and calcified human aortic valves and valvular interstitial cells (VICs) isolated from normal and calcified human aortic valves were checked. HVICs were cultured in osteogenic medium as an in vitro model, and BMAL1 expression and location were detected. TGF-β and RhoA/ROCK inhibitors and RhoA-siRNA were applied to detect the mechanism underlying the source of BMAL1 during HVICs’ osteogenic differentiation. ChIP was applied to check whether BMAL1 could directly interact with the runx2 primer CPG region, and the expression of key proteins involved in the TNF signaling pathway and NF-κ B pathway was tested after silencing BMAL1. Results: In this study, we found that BMAL1 expression was elevated in calcified human aortic valves and VICs isolated from calcified human aortic valves. Osteogenic medium could promote BMAL1 expression in HVICs and the knockdown of BMAL1 induced the inhibition of HVICs’ osteogenic differentiation. Furthermore, the osteogenic medium promoting BMAL1 expression could be blocked by TGF-β and RhoA/ROCK inhibitors and RhoA-siRNA. Meanwhile, BMAL1 could not bind with the runx2 primer CPG region directly, but knockdown of BMAL1 led to decreased levels of P-AKT, P-IκBα, P-p65 and P-JNK. Conclusions: Osteogenic medium could promote BMAL1 expression in HVICs through the TGF-β/RhoA/ROCK pathway. BMAL1 could not act as a transcription factor, but functioned through the NF-κ B/AKT/MAPK pathway to regulate the osteogenic differentiation of HVICs.

Screening for key genes in circadian regulation in advanced atherosclerosis: A bioinformatic analysis

Background

Atherosclerosis (AS) is the most important cardiovascular disease threatening human health, leading to adverse events such as myocardial infarction and stroke. The research on the pathogenesis and causes of AS is being improved step by step, and many factors are associated with AS. However, the relationship between circadian regulation and the pathogenesis of AS is still unclear. Our study identified 2 key genes of circadian regulation in AS by bioinformatics analysis, which provides new perspectives to understand the relationship between circadian rhythm and AS.

Methods

We downloaded samples of early and advanced AS from public databases, screened key genes by weighted gene co-expression network analysis (WGCNA) and Lasso, calculated the immune cell content of the samples using "CIBERSORT," and analyzed the relationship between key genes and immune cells.

Results

We obtained the most relevant core modules for advanced AS and analyzed the functions of these modules. Two circadian rhythm-related genes were obtained, which influence the immune infiltration of this late AS. ROC curves demonstrated the efficacy of key genes to differentiate between early and advanced AS.

Conclusion

We identified 2 genes most associated with circadian rhythms in advanced AS, whose association with AS has not been elucidated and may become the next therapeutic target.

The time dimension to stroke: Circadian effects on stroke outcomes and mechanisms

The circadian system is widely involved in the various pathological outcomes affected by time dimension changes. In the brain, the master circadian clock, also known as the "pacemaker," is present in the hypothalamus's suprachiasmatic nucleus (SCN). The SCN consists of molecular circadian clocks that operate in each neuron and other brain cells. These circadian mechanisms are controlled by the transcription and translation of specific genes such as the clock circadian regulator (Clock) and brain and muscle ARNT-Like 1 (Bmal1). Period (Per1-3) and cryptochrome (Cry1 and 2) negatively feedback and regulate the clock genes. Variations in the circadian cycle and these clock genes can affect stroke outcomes. Studies suggest that the peak stroke occurs in the morning after patients awaken from sleep, while stroke severity and poor outcomes worsen at midnight. The main risk factor associated with stroke is high blood pressure (hypertension). Blood pressure usually dips by 15-20% during sleep, but many hypertensives do not display this normal dipping pattern and are non-dippers. A sleep blood pressure is the primary determinant of stroke risk. This article discusses the possible mechanism associated with circadian rhythm and stroke outcomes.

Protective effects of brain and muscle ARNT-like gene 1 on oxidized low-density lipoprotein-induced human brain microvascular endothelial cell injury by alleviating ferroptosis

Ferroptosis plays an important role in atherosclerotic cerebrovascular diseases. The brain and muscle ARNT-like gene 1 (BMAL1) is an important mediator in the progression of cerebrovascular diseases. However, whether BMAL1 regulates ferroptosis in atherosclerotic cerebrovascular diseases remains obscure. Here, human brain microvascular endothelial cells (HBMECs) were exposed to oxidized low-density lipoprotein (ox-LDL) to imitate cerebrovascular atherosclerosis. It was found that ox-LDL treatment induced ferroptosis events and reduced BMAL1 expression in HBMECs, which could be reversed by ferroptosis inhibitor ferrostatin-1. Furthermore, BMAL1 overexpression markedly mitigated ox-LDL-induced ferroptosis events and cell damage. Moreover, BMAL1 overexpression significantly promoted nuclear factor erythroid 2-related factor 2 (Nrf2) expression in HBMECs under ox-LDL conditions. And, Nrf2 silencing attenuated the protective effects of BMAL1 on ox-LDL-stimulated HBMEC damage and ferroptosis. Altogether, our findings delineate the cerebrovascular protective role of BMAL1/Nrf2 by antagonizing ferroptosis in response to ox-LDL stimulation and provide novel perspectives for therapeutic strategies for atherosclerotic cerebrovascular diseases.

Identification and characterization of non-coding RNA networks in infected macrophages revealing the pathogenesis of F. nucleatum-associated diseases

BACKGROUND

F. nucleatum, as an important periodontal pathogen, is not only closely associated with the development of periodontitis, but also implicated in systemic diseases. Macrophages may act as an important mediator in the pathogenic process of F. nucleatum infection. As non-coding RNAs (ncRNAs) have attracted extensive attention as important epigenetic regulatory mechanisms recently, we focus on the competing endogenous RNA (ceRNA) regulatory networks to elucidate the pathogenesis of F. nucleatum-associated diseases.

RESULTS

We screen abnormally expressed mRNAs, miRNAs, lncRNAs and circRNAs in macrophages after F. nucleatum infection via the whole transcriptome sequencing technology, including 375 mRNAs, 5 miRNAs, 64 lncRNAs, and 180 circRNAs. The accuracy of RNA-seq and microRNA-seq result was further verified by qRT-PCR analysis. GO and KEGG analysis show that the differentially expressed genes were mainly involved in MAPK pathway, Toll-like receptor pathway, NF-κB pathway and apoptosis. KEGG disease analysis reveals that they were closely involved in immune system diseases, cardiovascular disease, cancers, inflammatory bowel disease (IBD) et al. We constructed the underlying lncRNA/circRNA-miRNA-mRNA networks to understand their interaction based on the correlation analysis between the differentially expressed RNAs, and then screen the core non-coding RNAs. In which, AKT2 is controlled by hsa_circ_0078617, hsa_circ_0069227, hsa_circ_0084089, lncRNA NUP210, lncRNA ABCB9, lncRNA DIXDC1, lncRNA ATXN1 and lncRNA XLOC_237387 through miR-150-5p; hsa_circ_0001165, hsa_circ_0008460, hsa_circ_0001118, lncRNA XLOC_237387 and lncRNA ATXN1 were identified as the ceRNAs of hsa-miR-146a-3p and thereby indirectly modulating the expression of MITF.

CONCLUSIONS

Our data identified promising candidate ncRNAs responsible for regulating immune response in the F. nucleatum-associated diseases, offering new insights regarding the pathogenic mechanism of this pathogen.

Erfüllte Gegenwart und Rhythmus des Lebens

Der Zusammenhang von Zeit und gutem Leben wurde bereits für eine Reihe medizinischer Disziplinen und Praktiken herausgearbeitet. Doch welche Rolle spielt die Zeitlichkeit des guten Lebens für die Medizin insgesamt? Das ist die leitende Frage dieses Artikels. Dabei wird das gute Leben als sinnvolles Leben verstanden. In diesem Sinne wird für eine zweifache medizinische Relevanz der Zeitlichkeit des guten Lebens argumentiert: Erstens besteht der Sinn medizinischer Behandlungen in der Ermöglichung erfüllter Gegenwart. Zweitens kann und sollte ebendies u. a. durch die Wahrung und Wiederherstellung der chronobiologischen Rhythmen geschehen.

Cardioprotective Properties of Phenolic Compounds: A Role for Biological Rhythms

Cardiovascular diseases (CVD) are the leading cause of deaths worldwide and their prevalence is continuously increasing. Available treatments may present several side effects and therefore the development of new safer therapeutics is of interest. Phenolic compounds have shown several cardioprotective properties helpful in reducing different CVD risk factors such as inflammation, elevated blood pressure, hyperlipidemia, or endothelial dysfunction. These factors are significantly influenced by biological rhythms which are in fact emerging as key modulators of important metabolic and physiological processes. Thus, increased events of CVD have been observed under circadian rhythm disruption or in winter versus other seasons. These rhythms can also affect the functionality of phenolic compounds. Indeed, different effects have been observed depending on the administration time or under different photoperiods. Therefore, in this review the focus will be on the potential of phenolic compounds as therapeutics to prevent CVD via biological rhythm modulation.

Metabolic profiling of night shift work - The HORMONIT study

Mechanistic studies are needed to understand how rotating shift work perturbs metabolic processing. We collected plasma samples (n = 196) from 49 males, rotating car factory shift workers at the beginning and end of a night-shift (22:00-06:00 h) and day-shift (06:00 h-14:00 h). Samples underwent targeted LC-MS/MS metabolomics and concentrations of 130 metabolites were log2-transformed and pareto-scaled. An elastic net selected the most influential metabolites for linear mixed models examining within-person variation in metabolite levels at night-shift end (06:00 h) compared to day-shift start (06:00 h). Quantitative enrichment analysis explored differentially enriched biological pathways between sample time points. We included 20 metabolites (amino acids, biogenic amines, acylcarnitines, glycerophospholipids) in mixed models. Night-shift was associated with changes in concentrations of arginine (geometric mean ratio [GMR] 2.30, 95%CI 1.25, 4.23), glutamine (GMR 2.22, 95%CI 1.53, 3.24), kynurenine (GMR 3.22, 95%CI 1.05, 9.87), lysoPC18:2 (GMR 1.86, 95%CI 1.11, 3.11), lysoPC20:3 (GMR 2.48, 95%CI 1.05, 5.83), PCaa34:2 (GMR 2.27, 95%CI 1.16, 4.44), and PCae38:5 (GMR 1.66, 95%CI 1.02, 2.68). Tryptophan metabolism, glutathione metabolism, alanine metabolism, glycine and serine metabolism, and urea cycle were pathways differing between shifts. Night shift work was associated with changes in metabolites and the perturbation of metabolic and biochemical pathways related to a variety of health outcomes.

Leukocyte telomere length, allelic variations in related genes and risk of coronary heart disease in people with long-standing type 1 diabetes

Background

Type 1 diabetes is associated with accelerated vascular aging and advanced atherosclerosis resulting in increased rates of cardiovascular disease and premature death. We evaluated associations between Leukocyte telomere length (LTL), allelic variations (SNPs) in LTL-related genes and the incidence of coronary heart disease (CHD) in adults with long-standing type 1 diabetes.

Methods

We assessed associations of LTL, measured at baseline by RT–PCR, and of SNPs in 11 LTL-related genes with the risk of coronary heart disease (CHD: myocardial infarction or coronary revascularization) and all-cause death during follow-up in two multicenter French-Belgian prospective cohorts of people with long-standing type 1 diabetes.

Results

In logistic and Cox analyses, the lowest tertile of LTL distribution (short telomeres) at baseline was associated with the prevalence of myocardial infarction at baseline and with increased risk of CHD (Hazard ratio 3.14 (1.39–7.70), p = 0.005, for shorter vs longer tertile of LTL) and all-cause death (Hazard ratio 1.63 (95% CI 1.04–2.55), p = 0.03, for shorter vs combined intermediate and longer tertiles of LTL) during follow-up. Allelic variations in six genes related to telomere biology (TERC, NAF1, TERT, TNKS, MEN1 and BICD1) were also associated with the incidence of CHD during follow-up. The associations were independent of sex, age, duration of diabetes, and a range of relevant confounding factors at baseline.

Conclusions

Our results suggest that short LTL is an independent risk factor for CHD in people with type 1 diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01635-0.

Combining body mass index with waist circumference to assess coronary microvascular function in patients with non-obstructive coronary artery disease

BACKGROUND

Coronary microvascular dysfunction (CMD) may precede clinically overt coronary artery disease (CAD). Overall and central obesity (CO) are major risk factors for CAD. This study sought to investigate the subclinical significance of body adiposity patterns based on the CMD risk.

METHODS

A total of 128 patients with non-obstructive CAD were prospectively enrolled. Patients were categorized into 4 anthropometric groups: normal weight and non-CO (NWNCO, n = 41), normal weight and CO (NWCO, n = 20), excess weight and non-CO (EWNCO, n = 26), and excess weight and CO (EWCO, n = 41). Patients underwent rest/stress electrocardiography-gated 13N-ammonia positron emission tomography to measure absolute myocardial blood flow (MBF), myocardial flow reserve (MFR), hemodynamic parameters, and cardiac function.

RESULTS

Resting MBF did not differ between groups (P = .36). Compared with the NWNCO group, hyperemic MBF and MFR were significantly lower in the NWCO and EWCO groups. Notably, patients with NWCO presented the lowest hyperemic MBF and MFR and the highest incidence of CMD. Waist circumference was an independent risk factor for CMD (OR 1.05, 95% CI 1.01 to 1.10, P = .02).

CONCLUSION

In patients with non-obstructive CAD, CO may be associated with an increased risk of CMD to better fit the study findings which did not assess management or monitoring of MBF and MFR.

Circadian rhythms in ischaemic heart disease: key aspects for preclinical and translational research: position paper of the ESC working group on cellular biology of the heart

Circadian rhythms are internal regulatory processes controlled by molecular clocks present in essentially every mammalian organ that temporally regulate major physiological functions. In the cardiovascular system, the circadian clock governs heart rate, blood pressure, cardiac metabolism, contractility, and coagulation. Recent experimental and clinical studies highlight the possible importance of circadian rhythms in the pathophysiology, outcome, or treatment success of cardiovascular disease, including ischaemic heart disease. Disturbances in circadian rhythms are associated with increased cardiovascular risk and worsen outcome. Therefore, it is important to consider circadian rhythms as a key research parameter to better understand cardiac physiology/pathology, and to improve the chances of translation and efficacy of cardiac therapies, including those for ischaemic heart disease. The aim of this Position Paper by the European Society of Cardiology Working Group Cellular Biology of the Heart is to highlight key aspects of circadian rhythms to consider for improvement of preclinical and translational studies related to ischaemic heart disease and cardioprotection. Applying these considerations to future studies may increase the potential for better translation of new treatments into successful clinical outcomes.

Disruption of cellular immune response among male rotating night shift workers in Spain– The HORMONIT study

Introduction

Preliminary studies suggest that night shift work is associated with a desynchronization of rhythmic immune markers, possibly explaining the increased risk of infection, cardiometabolic disorders, and cancer in shift workers.

Methods

This study included 51 male rotating shift workers from a car industry in Barcelona, Spain, sampled twice toward the end of a 3-week night shift (22:00-06:00 h) and a 3-week day shift (06:00-14:00 h) rotation. We collected four blood samples per worker, at the start and end of each shift. We measured 27 cytokines, chemokines and growth factors in plasma samples by luminex using the Cytokine Human Magnetic 30-Plex Panel LHC6003M and applied linear mixed models to examine within-person associations between shift work and analytes’ concentrations, comparing samples taken at 06:00 h on a day and night shift. We also conducted a factor analysis using analyte concentrations from all 4 time points for each individual to identify common factors and determine if these factors were altered by shift work.

Results

We observed lower levels of 15 analytes in the night shift compared to the day shift including cytokines (pro-inflammatory TNF-α, IL-2R; anti-inflammatory IL1-RA; Th1 IL-2, Th2 IL-4 and Th17 Il-17), chemokines (IP-10, MIP-1α, MIP-1β, RANTES) and growth factors (EGF, G-CSF, HGF, VEGF, FGF). In a factor analysis, three factors were identified. The main factor (Factor 1), explaining 57% of the variance and including IL-1β, IL-12, IL-15, MIP-1α, MIP-1β, EGF and FGF; and another factor (Factor 3) explaining 10% of the variance and including the Th1 cytokine IL-12, were inversely associated with the night shift (coefficient: -0.17, 95%CI -0.32 to -0.01 and coefficient: -0.22, 95%CI -0.38, -0.06, for Factors 1 and 3, respectively). Our results indicate that night shift disrupts the levels of several immune markers, which could contribute to the increased risk of infections and cancer reported in night shift workers.

Conclusion

Night shift is associated with disruption of multiple immune response pathways.

Association between rotating night shift work and carotid intima-media thickness among Chinese steelworkers: a cross-sectional survey

OBJECTIVE

This study aimed to examine the association between rotating night shift work and subclinical athero-sclerosis among Chinese steelworkers.

METHODS

We evaluated 3582 steelworkers who participated in the legally required health examination in 2017. Carotid intima-media thickness (CIMT) was measured using ultrasonography. Different exposure metrics of night shifts collected by face-to-face personal interviews were used to examine the relationship between night shift work and the mean CIMT.

RESULTS

The mean CIMT values were 0.66 (standard deviation 0.22) mm in the study population. Current shift workers shown higher mean CIMT compared to day workers. There were no significant associations between the current shift status, the duration of night shifts, the cumulative number of night shifts, the average frequency of night shifts, and the mean CIMT after all confounding factors adjusted both in male and female.

CONCLUSIONS

Rotating night shift work is not associated with subclinical atherosclerosis among steelworkers. Further large-scale prospective longitudinal studies are warranted to confirm our findings.

The PAICE suite reveals circadian posttranscriptional timing of noncoding RNAs and spliceosome components in Mus musculus macrophages

Circadian rhythms broadly regulate physiological functions by tuning oscillations in the levels of mRNAs and proteins to the 24-h day/night cycle. Globally assessing which mRNAs and proteins are timed by the clock necessitates accurate recognition of oscillations in RNA and protein data, particularly in large omics data sets. Tools that employ fixed-amplitude models have previously been used to positive effect. However, the recognition of amplitude change in circadian oscillations required a new generation of analytical software to enhance the identification of these oscillations. To address this gap, we created the Pipeline for Amplitude Integration of Circadian Exploration suite. Here, we demonstrate the Pipeline for Amplitude Integration of Circadian Exploration suite's increased utility to detect circadian trends through the joint modeling of the Mus musculus macrophage transcriptome and proteome. Our enhanced detection confirmed extensive circadian posttranscriptional regulation in macrophages but highlighted that some of the reported discrepancy between mRNA and protein oscillations was due to noise in data. We further applied the Pipeline for Amplitude Integration of Circadian Exploration suite to investigate the circadian timing of noncoding RNAs, documenting extensive circadian timing of long noncoding RNAs and small nuclear RNAs, which control the recognition of mRNA in the spliceosome complex. By tracking oscillating spliceosome complex proteins using the PAICE suite, we noted that the clock broadly regulates the spliceosome, particularly the major spliceosome complex. As most of the above-noted rhythms had damped amplitude changes in their oscillations, this work highlights the importance of the PAICE suite in the thorough enumeration of oscillations in omics-scale datasets.

Dark-light cycle disrupts bone metabolism and suppresses joint deterioration in osteoarthritic rats

Background

Light alteration affects the internal environment and metabolic homeostasis of the body through circadian rhythm disorders (CRD). CRD is one of the factors that induce and accelerate osteoarthritis (OA). Therefore, the aim of this study was to evaluate the effects of continuous dark-light (DL) cycle on joint inflammation, bone structure, and metabolism in normal and OA Sprague-Dawley (SD) rats.

Methods

Interleukin (IL)-1β, IL-6, inducible nitric oxide synthase (iNOS), and tumor necrosis factor (TNF)-α were used to evaluate the systemic inflammation in rats. The pathological changes and inflammatory reactions of the cartilage and synovium of the knee joint in rats were evaluated by Safranin O-fast green and immunological staining. Bone turnover was assessed by histomorphometry and μCT scanning, as well as bone metabolism markers and proteins. The expression changes of clock proteins BMAL1, NR1D1, PER3, and CRY1 in representative tissues were detected by western blotting.

Results

DL cycle significantly inhibited body weight gain in normal and OA rats. The levels of proinflammatory factors in the peripheral blood circulation and degradation enzymes in the cartilage were significantly decreased in OA+DL rats. DL cycle significantly destroyed the structure of subchondral bone in hindlimbs of OA rats and reduced trabecular bone numbers. The decrease of bone mineral density (BMD), percent bone volume with respect to total bone volume (BV/TV), trabecular number (TB.N), osteoclast number, and mineralization could also be found. The ratio of the receptor activator of nuclear factor-kappa B ligand/osteoprotegerin (RANKL/OPG) in the bone marrow of OA rats was markedly increased under DL, along with the activation of the mononuclear/phagocyte system. The expression of representative clock proteins and genes BMAL1, PER3, and CRY1 were markedly changed in the tissues of OA+DL rats.

Conclusions

These results suggested that DL cycle dampened the arthritis and promoted bone resorption and bone mass loss.

Graphical abstract

DL cycle affects bone turnover by regulating osteoclast production in osteoarthritic rats.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02832-8.

Shift Work, Genetic Factors, and the Risk of Heart Failure: A Prospective Study of the UK Biobank

OBJECTIVE

To quantify the association of combined shift work and genetic factors with the incidence of heart failure (HF).

PARTICIPANTS AND METHODS

This study included 242,754 participants with complete shift work information in the UK Biobank. Participants were followed from baseline (2006 to 2010) through January 31, 2018. The association between shift work and HF incidence was investigated separately in males and females using a Cox proportional hazards model adjusted for covariates. In addition, we established a polygenic risk score and assessed whether shift work alters genetic susceptibility to HF.

RESULTS

The results showed a significant association of permanent night shift work with incident HF among females (hazard ratio, 2.25; 95% CI, 1.34 to 3.76; P=.002) after adjusting for age, and the association was attenuated in the fully adjusted model. Among men, we did not detect an association between shift work and HF. In addition, we observed that the association between the risk of HF and shift work was strengthened by high genetic risk. Permanent night shift work paired with high genetic risk, compared with low genetic risk, was suggested to be associated with the risk of HF in females (hazard ratio, 2.89; 95% CI, 1.05 to 7.94) but not in males.

CONCLUSION

Shift work, particularly permanent night shift work, may increase the risk of HF in females, especially in those with high genetic risk.

Circadian rhythm disorders elevate macrophages cytokines release and promote multiple tissues/organs dysfunction in mice

BACKGROUND

Circadian rhythm disorders are severe threats to human health. The negative impact of circadian rhythm disorders on tissues/organs has not been systematically analyzed. Therefore, there is an urgent need to evaluate the damage caused by circadian rhythm disorders and explore the possible mechanisms.

METHODS

Six-week-old male mice were divided into the control (Con) group (normal circadian rhythm), L24 group (constant light), D12L12 group (weekly shift light/dark cycle), and D24 group (constant dark). Body weight was recorded every 10 days. Ninety days after model construction, the serum lipid and cytokine level, liver function, fat accumulation, carotid artery stenosis, and cardiomyopathological changes were detected in mice. Macrophages in the liver, subscapular fat, and heart tissues were labeled with immunofluorescence staining. Mouse peritoneal macrophages were then isolated. Inflammatory cytokine levels were measured in the macrophage supernatant. The ability of macrophages to form foam cells was also tested. The supernatant from macrophages in different groups was added to AML12 (hepatocytes), 3T3-L1 (preadipocytes), or HL-1 (cardiomyocytes). Effects of conditioned media on recipient cells were determined.

RESULTS

Body weight, serum lipids and cytokines, subscapular fat accumulation, liver enzymes, carotid artery stenosis, and myocardial fibrosis levels of the L24, D12L12, and D24 groups mice were significantly higher than those in the Con group. Macrophages were significantly increased in the liver, heart, and subscapular fat of mice with circadian rhythmdisorders. Cytokine secretion by peritoneal macrophages was enhanced in the L24, D12L12, and D24 groups. Under oxidized low density lipoprotein (oxLDL) stimulation, macrophages with circadian rhythm disorders are more likely to form foam cells. Conditioned media from the L24, D12L12, and D24 groups significantly promoted AML12 apoptosis and lipid intake, accelerated the adipogenic differentiation of 3T3-L1, and up-regulated collagen I in HL-1.

CONCLUSION

These findings reveal that macrophages are increased in the tissues/organs under circadian rhythm disorders, and these macrophages could aggravate obesity, promote liver disease, accelerate atherosclerosis, and increase myocardial fibrosis through the paracrine effect.

Light-Control over Casein Kinase 1δ Activity with Photopharmacology: A Clear Case for Arylazopyrazole-Based Inhibitors

Protein kinases are responsible for healthy cellular processes and signalling pathways, and their dysfunction is the basis of many pathologies. There are numerous small molecule inhibitors of protein kinases that systemically regulate dysfunctional signalling processes. However, attaining selectivity in kinase inhibition within the complex human kinome is still a challenge that inspires unconventional approaches. One of those approaches is photopharmacology, which uses light-controlled bioactive molecules to selectively activate drugs only at the intended space and time, thereby avoiding side effects outside of the irradiated area. Still, in the context of kinase inhibition, photopharmacology has thus far been rather unsuccessful in providing light-controlled drugs. Here, we present the discovery and optimisation of a photoswitchable inhibitor of casein kinase 1δ (CK1δ), important for the control of cell differentiation, circadian rhythm, DNA repair, apoptosis, and numerous other signalling processes. Varying the position at which the light-responsive azobenzene moiety has been introduced into a known CK1δ inhibitor, LH846, revealed the preferred regioisomer for efficient photo-modulation of inhibitory activity, but the photoswitchable inhibitor suffered from sub-optimal (photo)chemical properties. Replacement of the bis-phenyl azobenzene group with the arylazopyrazole moiety yielded a superior photoswitch with very high photostationary state distributions, increased solubility and a 10-fold difference in activity between irradiated and thermally adapted samples. The reasons behind those findings are explored with molecular docking and molecular dynamics simulations. Results described here show how the evaluation of privileged molecular architecture, followed by the optimisation of the photoswitchable unit, is a valuable strategy for the challenging design of the photoswitchable kinase inhibitors.

Investigating the relationship between melatonin patterns and methylation in circadian genes among day shift and night shift workers

OBJECTIVES

Mechanisms underlying the carcinogenicity of night shift work remain uncertain. One compelling yet understudied cancer mechanism may involve altered DNA methylation in circadian genes due to melatonin secretion patterns. The objective of this study was to explore the relationship between melatonin secretion patterns and circadian gene methylation among day and night shift workers.

METHODS

Female healthcare employees (n=38 day workers, n=36 night shift workers) for whom we had urinary 6-sulfatoxymelatonin secretion data from a previous study were recontacted. New blood samples were collected and used to measure methylation levels at 1150 CpG loci across 22 circadian genes using the Illumina Infinium MethylationEPIC beadchip. Linear regression was used to examine the association between melatonin (acrophase and mesor) and M values for each CpG site (false discovery rate, q=0.2), while testing for effect modification by shift work status.

RESULTS

Among night shift workers, a higher mesor (24 hours of mean production of melatonin) was associated with increased methylation in the body of RORA (q=0.02) and decreased methylation in the putative promoter region of MTNR1A (q=0.03). Later acrophase (ie, time of peak concentration) was associated with increased methylation in the putative promoter region of MTNR1A (q=0.20) and decreased methylation in the body of PER3 (q=0.20). No associations were identified among day workers.

CONCLUSIONS

In conclusion, patterns in melatonin secretion were associated with differential circadian gene methylation among night shift workers. Melatonin and alteration of DNA methylation in circadian genes may be one pathway towards increased cancer risk, although larger-scale studies examining multiple time points are needed.

Relationships between Indicators of Lower Extremity Artery Disease and miRNA Expression in Peripheral Blood Mononuclear Cells

Lower extremity artery disease (LEAD) is an underdiagnosed and globally underestimated vascular disease caused by the progressive and chronic formation of atherosclerotic plaques in the arteries of the lower limbs. Much evidence indicates that the abnormal course of pathophysiological processes underlying LEAD development is associated with altered miRNA modulatory function. In the presented study, relationships between miRNA expression and clinical indicators of this disease (ABI, claudication distance, length of arterial occlusion, Rutherford category, and plaque localization) were identified. MiRNA expression profiles were obtained using next-generation sequencing in peripheral blood mononuclear cells (PBMCs) of 40 LEAD patients. Correlation analysis performed using the Spearman rank correlation test revealed miRNAs related to ABI, claudication distance, and length of arterial occlusion. In the DESeq2 analysis, five miRNAs were found to be dysregulated in patients with Rutherford category 3 compared to patients with Rutherford category 2. No miRNAs were found to be differentially expressed between patients with different plaque localizations. Functional analysis performed using the miRNet 2.0 website tool determined associations of selected miRNAs with processes underlying vascular pathology, such as vascular smooth muscle cell differentiation, endothelial cell apoptosis, response to hypoxia, inflammation, lipid metabolism, and circadian rhythm. The most enriched functional terms for genes targeted by associated miRNAs were linked to regulation of the cell cycle, regulation of the transcription process, and nuclear cellular compartment. In conclusion, dysregulations of miRNA expression in PBMCs of patients with LEAD are indicative of the disease and could potentially be used in the prediction of LEAD progression.

Association between insomnia and subclinical atherosclerosis among Chinese steelworkers: a cross-sectional survey

Background

Insomnia is a common prevalent sleep disorder. Difficulty maintaining sleep or poor in quality in insomnia caused by disrupted or misaligned circadian rhythms may play an important role in the development of atherosclerosis. This study aimed to examine the association between insomnia and subclinical atherosclerosis in Chinese steelworkers.

Methods

A total of 3240 subjects from a large enterprise located in northern China were included in this study. The Athens Insomnia Scale (AIS) was used to assess the status of insomnia. Subclinical atherosclerosis was evaluated using ultrasonographic measurements of carotid plaque. Multivariable logistic regression was used to identify association between insomnia and carotid atherosclerosis.

Results

The overall prevalence of insomnia and carotid plaque were 35.3 and 31.7% in the study population. Compared with non-insomnia workers, significantly increased odds of carotid plaque were observed among insomnia workers after adjusting for potential confounders, odds ratio (OR) = 1.38, 95% confidence interval (CI): 1.17 to 1.63. Exposure to current shift work and insomnia simultaneously can significantly elevated the odds of carotid plaque.

Conclusion

Insomnia is associated with elevated odds of carotid atherosclerosis in male steelworkers. Insomnia problems of workers should receive further attention in occupational worker health interventions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13690-022-00834-1.

Cosmeceutical Therapy: Engaging the Repercussions of UVR Photoaging on the Skin's Circadian Rhythm

Sunlight is an important factor in regulating the central circadian rhythm, including the modulation of our sleep/wake cycles. Sunlight had also been discovered to have a prominent influence on our skin's circadian rhythm. Overexposure or prolonged exposure to the sun can cause skin photodamage, such as the formation of irregular pigmentation, collagen degradation, DNA damage, and even skin cancer. Hence, this review will be looking into the detrimental effects of sunlight on our skin, not only at the aspect of photoaging but also at its impact on the skin's circadian rhythm. The growing market trend of natural-product-based cosmeceuticals as also caused us to question their potential to modulate the skin's circadian rhythm. Questions about how the skin's circadian rhythm could counteract photodamage and how best to maximize its biopotential will be discussed in this article. These discoveries regarding the skin's circadian rhythm have opened up a completely new level of understanding of our skin's molecular mechanism and may very well aid cosmeceutical companies, in the near future, to develop better products that not only suppress photoaging but remain effective and relevant throughout the day.

Association Between Na, K, and Lipid Intake in Each Meal and Blood Pressure

Cardiovascular diseases (CVDs) are one of the leading causes of death worldwide, and one of the most significant risk factors for CVDs is high blood pressure. Blood pressure is associated with various nutrients, such as sodium, potassium, and cholesterol. However, research focusing on the timing of intake of these nutrients and blood pressure has not been conducted. In this study, we used dietary data and a questionnaire asking about the sleep, physical activity, and blood pressure, collected from the food-log app “Asken” (total N = 2,402), to investigate the relationship between the dietary data of nutrient intake in the breakfast, lunch, and dinner and blood pressure. Daily total intake of various nutrients such as sodium, sodium-to-potassium ratio, total energy, lipid, carbohydrate, and saturated fat showed a significant association with blood pressure depending on the meal timing. From multiple regression analysis, eliminating the confounding factors, lunch sodium-to-potassium ratio, dinner energy, lipid, cholesterol, saturated fat, and alcohol intake were positively associated with blood pressure, whereas breakfast protein and lunch fiber intake showed a negative association with blood pressure. Our results suggest that nutrient intake timing is also an important factor in the prevention of high blood pressure. Our study provides possibilities to prevent hypertension by changing the timing of nutrient intake, especially sodium, together with potassium and lipids. However, because our research was limited to food-log app users, broader research regarding the general population needs to be conducted.

Association between rotating night shift work and carotid atherosclerosis among Chinese steelworkers: a cross-sectional survey

This study aimed to examine the association between rotating night shift work and carotid atherosclerosis in Chinese steelworkers. A total of 3582 subjects were included in this study. Different exposure metrics of night shifts, including current shift status, duration of night shifts (years), the cumulative number of night shifts (nights), cumulative length of night shifts (hours) and average frequency of night shifts (nights/month), were used to examine the relationship between night shift work and carotid atherosclerosis, including carotid plaque and carotid plaque scores. The prevalence of carotid plaque was 29.9% in the study population. Compared with day workers, significantly increased odds of carotid plaque were observed among shift workers in each quartile of the duration of night shifts after adjusting for potential confounders, especially in the third and fourth quartiles: odds ratio (OR) = 1.91, 95% confidence interval (CI): 1.46 to 2.49, in the third quartiles; OR = 1.69, 95% CI: 1.30 to 2.20, in the fourth quartiles. Positive associations of different exposure metrics of night shifts (continuous) with the odds of carotid plaque and the carotid plaque score were observed in the restricted cubic spline (RCS) models. No significant association was found in female workers between night shift work and carotid plaque. Rotating night shift work is associated with elevated odds of carotid atherosclerosis in male steelworkers.

Abnormal Sleep Duration as Predictor for Cardiovascular Diseases: A Systematic Review of Prospective Studies

Methods

We searched the online database PubMed on 30 August 2020 for our data collection. We used the following keywords: sleep duration AND (cardiovascular disease OR cardiovascular event) AND (cohort OR prospective OR retrospective). We identified 653 studies, and after excluding studies that were published before 2015, we obtained 306 studies. After filtering the 306 studies through title and abstract screening and applying the inclusion and exclusion criteria, we further reviewed fourteen studies with full-text reading. We excluded three studies because of insufficient data required and included eleven studies in this systematic review.

Results

A total of 361,041 participants from ten studies were included in this systematic review. The incidence of hypertension, myocardial infarction, coronary artery disease, heart failure, cardiovascular events, and cardiovascular diseases in the short sleep duration group is 46.12%, 0.59%, 5.43%, 0.09%, 7.18%, 1.48%, and 6.8%, consecutively, while the incidence of hypertension, myocardial infarction, coronary artery disease, and heart failure in the long sleep duration group is 30.71%, 0.61%, 6.55%, 1.11%, and 6.04%, consecutively. Nine studies reported an association between sleep duration and cardiovascular diseases while one study reported no association. Seven studies reported that short sleep duration was significantly associated with CVD. Short sleep duration in this study was associated with hypertension and heart failure. Atrial fibrillation and coronary artery disease were associated with both short and long sleep duration.

Conclusion

Abnormal sleep duration (short and long sleep duration) may act as the predictor of cardiovascular diseases. The importance of having normal sleep duration should be stressed with other lifestyle modification to avoid the risk of getting cardiovascular diseases. However, further studies are needed to overcome the limitation of this systematic review.

Mucosal circadian rhythm pathway genes altered by aging and periodontitis

As circadian processes can impact the immune system and are affected by infections and inflammation, this study examined the expression of circadian rhythm genes in periodontitis.

METHODS

Macaca mulatta were used with naturally-occurring and ligature-induced periodontitis. Gingival tissue samples were obtained from healthy, diseased, and resolved sites in four groups: young (≤3 years), adolescent (3-7 years), adult (12-26) and aged (18-23 years). Microarrays targeted circadian rhythm (n = 42), inflammation/tissue destruction (n = 11), bone biology (n = 8) and hypoxia pathway (n = 7) genes.

RESULTS

The expression of many circadian rhythm genes, across functional components of the pathway, was decreased in healthy tissues from younger and aged animals, as well as showing significant decreases with periodontitis. Negative correlations of the circadian rhythm gene levels with inflammatory mediators and tissue destructive/remodeling genes were particularly accentuated in disease. A dominance of positive correlations with hypoxia genes was observed, except HIF1A, that was uniformly negatively correlated in health, disease and resolution.

CONCLUSIONS

The chronic inflammation of periodontitis exhibits an alteration of the circadian rhythm pathway, predominantly via decreased gene expression. Thus, variation in disease expression and the underlying molecular mechanisms of disease may be altered due to changes in regulation of the circadian rhythm pathway functions.

Potential Effect of the Circadian Clock on Erectile Dysfunction

The circadian rhythm is an internal timing system, which is generated by circadian clock genes. Because the circadian rhythm regulates numerous cellular, behavioral, and physiological processes, organisms have evolved with intrinsic biological rhythms to adapt the daily environmental changes. A variety of pathological events occur at specific times, while disturbed rhythms can lead to metabolic syndrome, vascular dysfunction, inflammatory disorders, and cancer. Therefore, the circadian clock is considered closely related to various diseases. Recently, accumulated data have shown that the penis is regulated by the circadian clock, while erectile function is impaired by an altered sleep-wake cycle. The circadian rhythm appears to be a novel therapeutic target for preventing and managing erectile dysfunction (ED), although research is still progressing. In this review, we briefly summarize the superficial interactions between the circadian clock and erectile function, while focusing on how disturbed rhythms contribute to risk factors of ED. These risk factors include NO/cGMP pathway, atherosclerosis, diabetes mellitus, lipid abnormalities, testosterone deficiency, as well as dysfunction of endothelial and smooth muscle cells. On the basis of recent findings, we discuss the potential role of the circadian clock for future therapeutic strategies on ED, although further relevant research needs to be performed.

The potential impacts of circadian rhythm disturbances on male fertility

A circadian rhythm is an internalized timing system that synchronizes the cellular, behavioral, and physiological processes of organisms to the Earth's rotation. Because all physiological activities occur at a specific time, circadian rhythm disturbances can lead to various pathological disorders and diseases. Growing evidence has shown that the circadian clock is tightly connected to male fertility, and circadian perturbations contribute to infertility. The night shiftwork, insufficient sleep, and poor sleep quality are common causes of circadian disturbances, and many studies have reported that they impair sperm quality and increase the risk of male infertility. However, research on the impacts of light, body temperature, and circadian/circannual rhythms is relatively lacking, although some correlations have been demonstrated. Moreover, as the index of sperm quality was diverse and study designs were non-uniform, the conclusions were temporarily inconsistent and underlying mechanisms remain unclear. A better understanding of whether and how circadian disturbances regulate male fertility will be meaningful, as more scientific work schedules and rational lifestyles might help improve infertility.

Exercise as a Peripheral Circadian Clock Resynchronizer in Vascular and Skeletal Muscle Aging

Aging is characterized by several progressive physiological changes, including changes in the circadian rhythm. Circadian rhythms influence behavior, physiology, and metabolic processes in order to maintain homeostasis; they also influence the function of endothelial cells, smooth muscle cells, and immune cells in the vessel wall. A clock misalignment could favor vascular damage and indirectly also affect skeletal muscle function. In this review, we focus on the dysregulation of circadian rhythm due to aging and its relationship with skeletal muscle changes and vascular health as possible risk factors for the development of sarcopenia, as well as the role of physical exercise as a potential modulator of these processes.

Chronic Circadian Rhythm Disturbance Accelerates Knee Cartilage Degeneration in Rats Accompanied by the Activation of the Canonical Wnt/β-Catenin Signaling Pathway

With the gradual deepening of understanding of systemic health and quality of life, the factors affecting osteoarthritis (OA) are not limited to mechanical injury, metabolic abnormality, age and obesity, etc., but circadian rhythm, which plays a non-negligible role in human daily life. The purpose of this study was to explore the molecular mechanism of chronic circadian rhythm disturbance (CRD) inducing cartilage OA-like degeneration. Rats with the anterior cruciate ligament excision transection (ACLT) were used to establish the early-stage OA model (6-week). The light/dark (LD) cycle shifted 12 h per week for 22 weeks in order to establish a chronic CRD model. BMAL1 knockdown (KD) and Wnt/β-catenin pathway inhibition were performed in chondrocytes. The contents of proinflammatory factors and OA biomarkers in serum and chondrocyte secretions were detected by ELISA. Pathological and immunohistochemical staining of articular cartilage indicated the deterioration of cartilage. WB and qPCR were used to evaluate the relationship between matrix degradation and the activation of Wnt/β-catenin signaling pathway in chondrocytes. We found that chronic CRD could cause OA-like pathological changes in knee cartilage of rats, accelerating cartilage matrix degradation and synovial inflammation. The expression of MMP-3, MMP-13, ADAMTS-4, and β-catenin increased significantly; BMAL1, Aggrecan, and COL2A1 decreased significantly in either LD-shifted cartilage or BMAL1-KD chondrocytes. The expression of β-catenin and p-GSK-3β elevated, while p-β-catenin and GSK-3β diminished. The inhibitor XAV-939 was able to mitigated the increased inflammation produced by transfected siBMAL1. Our study demonstrates that chronic CRD disrupts the balance of matrix synthesis and catabolic metabolism in cartilage and chondrocytes, and it is related to the activation of the canonical Wnt/β-catenin signaling pathway.

Exploring the impact of night shift work on methylation of circadian genes

Night shift work is associated with increased breast cancer risk, but the molecular mechanisms are not well-understood. The objective of this study was to explore the relationship between night shift work parameters (current status, duration/years, and intensity) and methylation in circadian genes as a potential mechanism underlying the carcinogenic effects of night shift work. A cross-sectional study was conducted among 74 female healthcare employees (n = 38 day workers, n = 36 night shift workers). The Illumina Infinium MethylationEPIC beadchip was applied to DNA extracted from blood samples to measure methylation using a candidate gene approach at 1150 CpG loci across 22 circadian genes. Linear regression models were used to examine the association between night shift work parameters and continuous methylation measurements (β-values) for each CpG site. The false-discovery rate (q = 0.2) was used to account for multiple comparisons. Compared to day workers, current night shift workers demonstrated hypermethylation in the 5'UTR region of CSNK1E (q = 0.15). Individuals that worked night shifts for ≥10 years exhibited hypomethylation in the gene body of NR1D1 (q = 0.08) compared to those that worked <10 years. Hypermethylation in the gene body of ARNTL was also apparent in those who worked ≥3 consecutive night shifts a week (q = 0.18). These findings suggest that night shift work is associated with differential methylation in core circadian genes, including CSNK1E, NR1D1 and ARNTL. Future, larger-scale studies with long-term follow-up and detailed night shift work assessment are needed to confirm and expand on these findings.

Interactions between remote ischemic conditioning and post-stroke sleep regulation

Sleep disturbances are common in patients with stroke, and sleep quality has a critical role in the onset and outcome of stroke. Poor sleep exacerbates neurological injury, impedes nerve regeneration, and elicits serious complications. Thus, exploring a therapy suitable for patients with stroke and sleep disturbances is imperative. As a multi-targeted nonpharmacological intervention, remote ischemic conditioning can reduce the ischemic size of the brain, improve the functional outcome of stroke, and increase sleep duration. Preclinical/clinical evidence showed that this method can inhibit the inflammatory response, mediate the signal transductions of adenosine, activate the efferents of the vagal nerve, and reset the circadian clocks, all of which are involved in sleep regulation. In particular, cytokines tumor necrosis factor α (TNFα) and adenosine are sleep factors, and electrical vagal nerve stimulation can improve insomnia. On the basis of the common mechanisms of remote ischemic conditioning and sleep regulation, a causal relationship was proposed between remote ischemic conditioning and post-stroke sleep quality.

Brazilian passion fruit as a new healthy food: from its composition to health properties and mechanisms of action

The Brazilian biodiversity is one of the largest in the world, with about 41 000 species cataloged within two global biodiversity hotspots: Atlantic Forest and Cerrado, the Brazilian savannah. Passiflora, known also as passion flowers, is a genus of which 96% of its species are distributed in the Americas, mainly Brazil and Colombia. Passion fruit extracts have a commercial value on a global scale through the pharmaceutical, nutraceutical, self-care, and food and beverage industries. Passiflora are widely studied due to their potential antioxidant, anti-inflammatory, anxiolytic, antidepressant and vascular and neuronal protective effects, probably owing to their content of polyphenols. Passiflora setacea DC is a species of wild passion fruit from the Brazilian Cerrado, rich in flavonoid C-glycosides, homoorientin, vitexin, isovitexin and orientin. Intake of these plant food bioactives has been associated with protection against chronic non-communicable diseases (CNDCs), including cardiovascular diseases, cancers, and neurodegenerative diseases. In this review, we aimed to discuss the varieties of Passiflora, their content in plant food bioactives and their potential molecular mechanisms of action in preventing or reversing CNDCs.

Alzheimer's Disease, Sleep Disordered Breathing, and Microglia: Puzzling out a Common Link

Sleep Disordered Breathing (SDB) and Alzheimer's Disease (AD) are strongly associated clinically, but it is unknown if they are mechanistically associated. Here, we review data covering both the cellular and molecular responses in SDB and AD with an emphasis on the overlapping neuroimmune responses in both diseases. We extensively discuss the use of animal models of both diseases and their relative utilities in modeling human disease. Data presented here from mice exposed to intermittent hypoxia indicate that microglia become more activated following exposure to hypoxia. This also supports the idea that intermittent hypoxia can activate the neuroimmune system in a manner like that seen in AD. Finally, we highlight similarities in the cellular and neuroimmune responses between SDB and AD and propose that these similarities may lead to a pathological synergy between SDB and AD.

Telomere Attrition and Clonal Hematopoiesis of Indeterminate Potential in Cardiovascular Disease

Clinical evidence suggests that conventional cardiovascular disease (CVD) risk factors cannot explain all CVD incidences. Recent studies have shown that telomere attrition, clonal hematopoiesis of indeterminate potential (CHIP), and atherosclerosis (telomere-CHIP-atherosclerosis, TCA) evolve to play a crucial role in CVD. Telomere dynamics and telomerase have an important relationship with age-related CVD. Telomere attrition is associated with CHIP. CHIP is commonly observed in elderly patients. It is characterized by an increase in blood cell clones with somatic mutations, resulting in an increased risk of hematological cancer and atherosclerotic CVD. The most common gene mutations are DNA methyltransferase 3 alpha (DNMT3A), Tet methylcytosine dioxygenase 2 (TET2), and additional sex combs-like 1 (ASXL1). Telomeres, CHIP, and atherosclerosis increase chronic inflammation and proinflammatory cytokine expression. Currently, their epidemiology and detailed mechanisms related to the TCA axis remain incompletely understood. In this article, we reviewed recent research results regarding the development of telomeres and CHIP and their relationship with atherosclerotic CVD.

Nuclear Receptors and Clock Components in Cardiovascular Diseases

Cardiovascular diseases (CVD) are still the first cause of death worldwide. Their main origin is the development of atherosclerotic plaque, which consists in the accumulation of lipids and inflammatory leucocytes within the vascular wall of large vessels. Beyond dyslipidemia, diabetes, obesity, hypertension and smoking, the alteration of circadian rhythms, in shift workers for instance, has recently been recognized as an additional risk factor. Accordingly, targeting a pro-atherogenic pathway at the right time window, namely chronotherapy, has proven its efficiency in reducing plaque progression without affecting healthy tissues in mice, thus providing the rationale of such an approach to treat CVD and to reduce drug side effects. Nuclear receptors are transcriptional factors involved in the control of many physiological processes. Among them, Rev-erbs and RORs control metabolic homeostasis, inflammatory processes and the biological clock. In this review, we discuss the opportunity to dampen atherosclerosis progression by targeting such ligand-activated core clock components in a (chrono-)therapeutic approach in order to treat CVD.

The Vascular Circadian Clock in Chronic Kidney Disease

Chronic kidney disease is associated with extremely high cardiovascular mortality. The circadian rhythms (CR) have an impact on vascular function. The disruption of CR causes serious health problems and contributes to the development of cardiovascular diseases. Uremia may affect the master pacemaker of CR in the hypothalamus. A molecular circadian clock is also expressed in peripheral tissues, including the vasculature, where it regulates the different aspects of both vascular physiology and pathophysiology. Here, we address the impact of CKD on the intrinsic circadian clock in the vasculature. The expression of the core circadian clock genes in the aorta is disrupted in CKD. We propose a novel concept of the disruption of the circadian clock system in the vasculature of importance for the pathology of the uremic vasculopathy.