Association between chronic kidney disease stages and changes in ambulatory blood pressure monitoring parameters / Associação entre estágios da doença renal crônica e alterações dos parâmetros da monitorização ambulatorial da pressão arterial

Abstract Introduction: Blood pressure (BP) assessment affects the management of arterial hypertension (AH) in chronic kidney disease (CKD). CKD patients have specific patterns of BP behavior during ambulatory blood pressure monitoring (ABPM). Objectives: The aim of the current study was to evaluate the associations between progressive stages of CKD and changes in ABPM. Methodology: This is a cross-sectional study with 851 patients treated in outpatient clinics of a university hospital who underwent ABPM examination from January 2004 to February 2012 in order to assess the presence and control of AH. The outcomes considered were the ABPM parameters. The variable of interest was CKD staging. Confounding factors included age, sex, body mass index, smoking, cause of CKD, and use of antihypertensive drugs. Results: Systolic BP (SBP) was associated with CKD stages 3b and 5, irrespective of confounding variables. Pulse pressure was only associated with stage 5. The SBP coefficient of variation was progressively associated with stages 3a, 4 and 5, while the diastolic blood pressure (DBP) coefficient of variation showed no association. SBP reduction was associated with stages 2, 4 and 5, and the decline in DBP with stages 4 and 5. Other ABPM parameters showed no association with CKD stages after adjustments. Conclusion: Advanced stages of CKD were associated with lower nocturnal dipping and greater variability in blood pressure.

Resumo Introdução: A avaliação da pressão arterial (PA) tem impacto no manejo da hipertensão arterial (HA) na doença renal crônica (DRC). O portador de DRC apresenta padrão específico de comportamento da PA ao longo da monitorização ambulatorial da pressão arterial (MAPA). Objetivos: O objetivo do corrente estudo é avaliar as associações entre os estágios progressivos da DRC e alterações da MAPA. Metodologia: Trata-se de um estudo transversal com 851 pacientes atendidos nos ambulatórios de um hospital universitário que foram submetidos ao exame de MAPA no período de janeiro de 2004 a fevereiro de 2012 para avaliar a presença e o controle da HA. Os desfechos considerados foram os parâmetros de MAPA. A variável de interesse foi o estadiamento da DRC. Foram considerados como fatores de confusão idade, sexo, índice de massa corporal, tabagismo, causa da DRC e uso de anti-hipertensivos. Resultados: A PA sistólica (PAS) se associou aos estágios 3b e 5 da DRC, independentemente das variáveis de confusão. Pressão de pulso se associou apenas ao estágio 5. O coeficiente de variação da PAS se associou progressivamente aos estágios 3a, 4 e 5, enquanto o coeficiente de variação da pressão arterial diastólica (PAD) não demonstrou associação. O descenso da PAS obteve associação com estágios 2, 4 e 5, e o descenso da PAD, com os 4 e 5. Demais parâmetros da MAPA não obtiveram associação com os estágios da DRC após os ajustes. Conclusão: Estágios mais avançados da DRC associaram-se a menor descenso noturno e a maior variabilidade da pressão arterial.

Transitional photoperiod induces a mania-like behavior in male mice.

This study aimed to investigate the behavioral responses and circadian rhythms of mice to both rapid and gradual increases in photoperiod, mimicking the transition from winter to summer, which is associated with a heightened prevalence of hospitalizations for mania and suicidal behavior. Behavioral tests were performed in C57BL/6 male mice exposed to a transitional photoperiod, from short to long durations. To determine if circadian rhythms are affected, we measured spontaneous locomotor activity and body temperature. Mice exhibited heightened exploratory and risk-taking behaviors compared with equatorial and static long (16:8 h of light-dark cycle for several days) groups. These behaviors were prevented by lithium. Spontaneous locomotor activity and body temperature rhythms persisted and were effectively synchronized; however, the relative amplitude of activity and interdaily stability were diminished. Additionally, the animals displayed increased activity during the light phase. Photoperiodic transition modulates behavior and circadian rhythms, mirroring certain features observed in bipolar disorder patients. This study introduces an animal model for investigating mania-like behavior induced by photoperiodic changes, offering potential insights for suicide prevention strategies and the management of mood disorders.

Circadian Rhythm-Regulated ADSC-Derived sEVs and a Triphasic Microneedle Delivery System to Enhance Tendon-to-Bone Healing.

Modulating the inflammatory microenvironment to reconstruct the fibrocartilaginous layer while promoting tendon repair is crucial for enhancing tendon-to-bone healing in rotator cuff repair (RCR), a persistent challenge in orthopedics. Small extracellular vesicles (sEVs) hold significant potential to modulate inflammation, yet the efficient production of highly bioactive sEVs remains a substantial barrier to their clinical application. Moreover, achieving minimally invasive local delivery of sEVs to the tendon-to-bone interface presents significant technical difficulties. Herein, the circadian rhythm of adipose-derived stem cells is modulated to increase the yield and enhance the inflammatory regulatory capacity of sEVs. Circadian rhythm-regulated sEVs (CR-sEVs) enhance the cyclic adenosine monophosphate signaling pathway in macrophage (Mφ) via platelet factor 4 delivery, thereby inhibiting Mφ M1 polarization. Subsequently, a triphasic microneedle (MN) scaffold with a tip, stem, and base is designed for the local delivery of CR-sEVs (CR-sEVs/MN) at the tendon-to-bone junction, incorporating tendon-derived decellularized extracellular matrix in the base to facilitate tendon repair. CR-sEVs/MN mitigates inflammation, promotes fibrocartilage regeneration, and enhances tendon healing, thereby improving biomechanical strength and shoulder joint function in a rat RCR model. Combining CR-sEVs with this triphasic microneedle delivery system presents a promising strategy for enhancing tendon-to-bone healing in clinical settings.

Circadian Temperature in Moderate to Severe Acute Stroke Patients.

Background: Stroke patients often present circadian disruption due to multiple causes e.g., primary disease, comorbidities, medication, immobilization, reduced daylight entrainment and sleep disturbances. Objective: To investigate the circadian rhythm of temperature in forehead skin in patients with moderate to severe stroke admitted for rehabilitation. Methods: A physiologic study in form of a secondary analysis of a former randomized study. In total 27 patients with moderate to severe stroke were included between May 1st 2014, and June 1st 2015. Circadian temperature was collected approx. seven days after admission at the acute stroke unit by a skin surface temperature probe as part of a Polysomnography (PSG) measurement. Results: Temperature variations show no circadian rhythm (Type 3 tests of fixed effects by SAS, p = 0.1610). The median temperature variance did fluctuate, but not significantly, and the small changes in circadian temperature variance did not follow the normal temperature variance. Conclusion: Patients with moderate to severe stroke show an abrogated circadian rhythm of temperature. There is an unmet need to understand the mechanisms for this, significance for stroke outcome and treatment.

Nobiletin promotes lipolysis of white adipose tissue in a circadian clock-dependent manner.

Nobiletin has been reported to protect against obesity-related metabolic disorders by enhancing the circadian rhythm; however its effects on lipid metabolism in adipose tissue are unclear. In this study, mice were fed with high-fat diet (HFD) for four weeks firstly and gavaged with 50 or 200 mg/kg bodyweight/day nobiletin at Zeitgeber time (ZT) 4 for another four weeks while still receiving HFD. At the end of the 8-week experimental period, the mice were sacrificed at ZT4 or ZT8 on the same day. Mature 3T3-L1 adipocytes were treated with nobiletin in the presence or absence of siBmal1, siRora, siRorc, SR8278 or SR9009. Nobiletin reduced the weight of white adipose tissue (WAT) and the size of adipocytes in WAT. At ZT4, nobiletin decreased the TG, TC and LDL-c levels and increased serum FFA level and glucose tolerance. Nobiletin triggered the lipolysis of mesenteric and epididymal WAT at both ZT4 and ZT16. Nobiletin increased the level of RORγ at ZT16, that of BMAL1 and PPARγ at ZT4, and that of ATGL at both ZT4 and ZT16. Nobiletin increased lipolysis and ATGL levels in 3T3-L1 adipocytes in Bmal1- or Rora/c- dependent manner. Dual luciferase assay indicated that nobiletin enhanced the transcriptional activation of RORα/γ on Atgl promoter and decreased the repression of RORα/γ on PPARγ-binding PPRE. Promoter deletion analysis indicated that nobiletin inhibited the suppression of PPARγ-mediated Atgl transcription by RORα/γ. Taken together, nobiletin elevated lipolysis in WAT by increasing ATGL levels through activating the transcriptional activity of RORα/γ and decreasing the repression of RORα/γ on PPARγ-binding PPRE.

Gender and circadian preferences influence emotions and motivation in secondary mathematics classrooms.

Many studies have reported poor school achievement in evening persons and general circadian fluctuations in cognition. The aim of this study was to analyze circadian fluctuations in a cross-sectional design and examine the effects of chronotype on situational emotions and intrinsic motivation. A cross-sectional survey study was conducted in three Turkish secondary schools with a total sample of 599 students (283 females and 316 males). Data were collected at the end of specific math lessons of the same grade level and content, using a form combining three scales. We found no gender-related differences in intrinsic motivation, while there were some differences in situational motivation. In math classes, female students exhibited higher level of interest, while boys scored higher on boredom. In addition, students who scored high on morning affect reported higher levels of interest, well-being, and less boredom. Students with higher stability (and lower fluctuations in mood and cognition during the day) reported a higher degree of enjoyment, perceived competence, perceived choice, and less pressure/tension in their math lessons. A positive association was observed between distinctness, interest, and well-being, while negative correlations existed between distinctness and boredom. This suggests that students with higher diurnal stability reported a higher level of interest, well-being, and a lower level of boredom. Additionally, the results of the analyses showed that morningness, distinctness, and eveningness were significant predictors of intrinsic motivation. Conversely, gender, time of application, morningness, and distinctness emerged as predictors for situational emotions in mathematics classes.

Daily Self-Monitoring and Feedback of Circadian Rhythm Measures in Major Depression and Bipolar Disorder Using Wearable Devices and Smartphones-The Circadian Rhythm for Mood (CRM®) Trial Protocol: A Randomized Sham Controlled Double-Blind Trial.

The circadian rhythm for mood (CRM) is a digital therapeutic, which aims to prevent mood episode and improve clinical course in patients with major mood disorders. Developed on the circadian rhythm hypothesis of mood disorder, CRM predicts the impending risk of mood episode with its built-in algorithm, utilizing wearable devices data and daily self-reports, and provides personalized feedback. In a pilot study of the CRM, the users experienced less frequent and shorter duration of mood episodes than the non-users. To investigate the efficacy of the upgraded CRM, a double-blind, randomized, sham-controlled, parallel-group trial is designed. Patients aged between 19 and 70, diagnosed with bipolar I disorder, bipolar II disorder, or major depressive disorder, in a euthymic state for more than two months, can participate. During this 12-month trial, participants are assessed for episode recurrence every three months, and the efficacy of the CRM as a potential digital therapeutic is evaluated. Trial registration: ClinicalTrials.gov Identifier: NCT05400785.

A Comparison of 06:00 AM Versus 09:00 AM Serum Cortisol as a Basal Morning Cortisol in Guwahati, Assam: A Pilot Study.

Introduction: Cortisol secretion is regulated by circadian rhythm, which is influenced by zeitgebers like light. In India, the entire country operates under a single time zone, Indian Standard Time, which may not align with the local sunrise timing across different regions. Aims: This study aimed to compare the basal serum cortisol levels between 06:00 AM and 09:00 AM in Guwahati, Assam, where sunrise occurs earlier compared with the western part of the country. A cross-sectional pilot study was conducted from December 2022 to June 2023 in a tertiary care hospital in Guwahati. Methods: Serum cortisol samples were collected at 06:00 AM and 09:00 AM from 25 healthy adult participants once in winter and again in summer. Descriptive statistics and paired Student's t-tests were used. Results: The mean serum cortisol levels at 06:00 AM in winter, summer and overall were 13.2, 13.4 and 13.3 µg/dL, respectively. At 09:00 AM, the mean serum cortisol levels in winter, summer and overall were 8.2, 7.7 and 8.0 µg/dL, respectively. Significant differences were observed between the 06:00 AM and 09:00 AM cortisol levels in both winter and summer (P <0.001). Conclusion: This study highlights the importance of considering the influence of earlier sunrise on circadian rhythm, cortisol secretion and sampling protocols. Recognising the impact of earlier sunrise on cortisol secretion and adapting sampling protocols accordingly to align with the local sunrise can provide a more accurate assessment of basal cortisol levels and help avoid potential misinterpretation and diagnostic challenges associated with low values.

The optimal measurement period of actigraphy for circadian rhythm in relation to adiposity: A retrospective case-control study.

BACKGROUND: This study focused on the relationship between adiposity and Rest-Activity Rhythms (RAR), utilizing both parametric cosine-based models and non-parametric algorithms. The emphasis was on the impact of varying measurement periods (7-28 days) on this relationship. METHODS: We retrieved actigraphy data from two datasets, encompassing a diverse cohort recruited from an obesity outpatient clinic and a workplace health promotion program. Participants were required to wear a research-grade wrist actigraphy device continuously for a minimum of four weeks. The final dataset included 115 individuals (mean age 40.7 ± 9.5 years, 51 % female). We employed both parametric and non-parametric methods to quantify RAR using six standard variables. Additionally, the study evaluated the correlations between three key adiposity indices - Body Mass Index (BMI), Visceral Adipose Tissue (VAT) area, and Body Fat Percentage (BF%) - and circadian rhythm indicators, controlling for factors like physical activity, age, and gender. RESULTS: The obesity group displayed a significantly lower relative amplitude (RA) as per non-parametric algorithm findings, with a decreased amplitude noted in the parametric algorithm analysis, in comparison to the overweight and control groups. The relationship between circadian rhythm indicators and adiposity metrics over 7- to 28-day periods was examined. A notable negative correlation was observed between RA and both BMI and VAT, while correlation coefficients between adiposity indicators and non-parametric circadian parameters increased with extended durations of actigraphy data. Specifically, RA over a 28-day period was significantly correlated with BF%, a trend not seen in the 7-day measurement (p = 0.094) in multivariate linear regression. The strength of the correlation between BF% and 28-day RA was more pronounced than that in the 7-day period (p = 0.044). However, replacing RA with amplitude as per parametric cosinor fitting yielded no significant correlations for any of the measurement periods. CONCLUSION: The study concludes that a 28-day measurement period more effectively captures the link between disrupted circadian rhythms and adiposity. Non-parametric algorithms, in particular, were more effective in characterizing disrupted circadian rhythms, especially when extending the measurement period beyond the standard 7 days.

Light-Dependent Circadian Rhythm Governs O-GlcNAc Cycling to Influence Cognitive Function in Adult Zebrafish.

This study explores the 24-h rhythmic cycle of protein O-GlcNAcylation within the brain and highlights its crucial role in regulating the circadian cycle and neuronal function based on zebrafish as an animal model. In our experiments, disruption of the circadian rhythm, achieved through inversion of the light-dark cycle or daytime melatonin treatment, not only impaired the rhythmic changes of O-GlcNAcylation along with altering expression patterns of O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) in zebrafish brain but also significantly impeded learning and memory function. In particular, circadian disruption affected rhythmic expression of protein O-GlcNAcylation and OGT in the nuclear fraction. Notably, the circadian cycle induces rhythmic alterations in O-GlcNAcylation of H2B histone protein that correspond to changes in H3 trimethylation. Disruption of the cycle interfered with these periodic histone code alterations. Pharmacological inhibition of OGT with OSMI-1 disrupted the wake-sleep patterns of zebrafish without affecting expression of circadian rhythm-regulating genes. OSMI-1 inhibited the expression of c-fos, bdnf, and calm1, key genes associated with brain function and synaptic plasticity, and decreased the binding of O-GlcNAcylated H2B and OGT to promoter regions of these genes. The collective findings support the potential involvement of circadian cycling of the O-GlcNAc histone code in regulating synaptic plasticity and brain function. Overall, data from this study provide evidence that protein O-GlcNAcylation serves as a pivotal posttranslational mechanism integrating circadian signals and neuronal function to regulate rhythmic physiology.

Reciprocal Coupling of Circadian Clocks in the Compound Eye and Optic Lobe in the Cricket Gryllus bimaculatus.

The circadian system comprises multiple clocks, including central and peripheral clocks. The central clock generally governs peripheral clocks to synchronize circadian rhythms throughout the animal body. However, whether the peripheral clock influences the central clock is unclear. This issue can be addressed through a system comprising a peripheral clock (compound eye clock [CE clock]) and central clock (the optic lobe [OL] clock) in the cricket Gryllus bimaculatus. We previously found that the compound eye regulates the free-running period (τ) and the stability of locomotor rhythms driven by the OL clock, as measured by the daily deviation of τ at 30°C. However, the role of the CE clock in this regulation remains unexplored. In this study, we investigated the importance of the CE clock in this regulation using RNA interference (RNAi) of the period (per) gene localized to the compound eye (perCE-RNAi). The perCE-RNAi abolished the compound eye rhythms of the electroretinogram (ERG) amplitude and clock gene expression but the locomotor rhythm driven by the OL clock was maintained. The locomotor rhythm of the tested crickets showed a significantly longer τ and greater daily variation of τ than those of control crickets treated with dsDsRed2. The variation of τ was comparable with that of crickets with the optic nerve severed. The τ was considerably longer but was comparable with that of crickets with the optic nerve severed. These results suggest that the CE clock regulates the OL clock to maintain and stabilize τ.

Gut microbiota and eating behaviour in circadian syndrome.

Eating behaviour and circadian rhythms are closely related. The type, timing, and quantity of food consumed, and host circadian rhythms, directly influence the intestinal microbiota, which in turn impacts host circadian rhythms and regulates food intake beyond homeostatic eating. This Opinion discusses the impact of food intake and circadian disruptions induced by an obesogenic environment on gut-brain axis signalling. We also explore potential mechanisms underlying the effects of altered gut microbiota on food intake behaviour and circadian rhythmicity. Understanding the crosstalk between gut microbiota, circadian rhythms, and unhealthy eating behaviour is crucial to addressing the obesity epidemic, which remains one of the biggest societal challenges of our time.

miRNA-mediated regulation of clock gene expression in men and women with colorectal cancer and possible consequences for disease management.

BACKGROUND: The incidence and mortality of colorectal cancer (CRC) are persistently higher in men than in women. CRC malignancy is strongly influenced by small non-coding RNAs (miRNAs). Moreover, deregulation of the circadian molecular oscillator has been associated with CRC facilitation. To analyse possible cumulative effects of the above-mentioned factors on CRC progression, we focused on functions of sex-biased miRNAs associated with the clock genes per2 and/or cry2, which are involved in the cell cycle control and DNA damage response. MAJOR FINDINGS: We identified miR-24, miR-92a, miR-181a, and miR-21 associated with per2 that are up-regulated in transformed colon tissue of men. miR-93, miR-17, miR-20a, and miR-24 with higher expression in males compared to females were linked to cry2. All these miRNAs possess oncogenic potential and exert their effects mainly via inhibition of the tumour suppressors phosphatase and tensin homolog (PTEN) and/or p53. Down-regulation of PTEN and p53 in men was further strengthened by inhibition of tumour suppressor per2. Oncogenic up-regulated miRNAs associated with per2 or cry2 in the transformed colon tissue of women were not detected. CONCLUSION: We conclude that the cancer-promoting, sex-biased miRNAs miR-24, miR-92a, miR-181a, miR-93, miR-17, miR-20a, and miR-21 associated with clock genes per2 and/or cry2 can contribute to the sex-dependent development of CRC via inhibition of the PTEN and p53 pathways.

Intrinsic Skeletal Muscle Function and Contraction-stimulated Glucose Uptake Do Not Vary by Time-of-day in Mice.

A growing body of data suggests that skeletal muscle contractile function and glucose metabolism vary by time-of-day, with chronobiological effects on intrinsic skeletal muscle properties being proposed as the underlying mediator. However, no studies have directly investigated intrinsic contractile function or glucose metabolism in skeletal muscle over a 24 h circadian cycle. To address this, we assessed intrinsic contractile function and endurance, as well as contraction-stimulated glucose uptake, in isolated extensor digitorum longus and soleus from mice at four times-of-day (zeitgeber times 1, 7, 13, 19). Significantly, though both muscles demonstrated circadian-related changes in gene expression, there were no differences between the four time points in intrinsic contractile function, endurance, and contraction-stimulated glucose uptake, regardless of sex. Overall, these results suggest that time-of-day variation in exercise performance and the glycemia-reducing benefits of exercise are not due to chronobiological effects on intrinsic muscle function or contraction-stimulated glucose uptake.

Influence of circadian rhythm on effects induced by mechanical strain in periodontal ligament cells.

PURPOSE: The aim of this study was to investigate the influence of mechanical strain on clock gene function in periodontal ligament (PDL) cells. Furthermore, we wanted to analyze whether effects induced by mechanical stress vary in relation to the circadian rhythm. METHODS: Human PDL fibroblasts were synchronized in their circadian rhythm with dexamethasone and stretched over 24 h. Unstretched cells served as controls. Gene expression of the core clock genes were analyzed at 4 h intervals by quantitative real-time polymerase chain reaction (qRT-PCR). Time points 0 h (group SI1) and 12 h (group SI2) after synchronization served as starting points of a 4 h force application period. Collagen-1α (COL-1α/Col-1α), interleukin-1ß (IL1-ß), and runt-related transcription factor 2 (RUNX2/Runx2) were assessed by qRT-PCR and enzyme-linked immunosorbent assay (ELISA) after 2 and 4 h. Statistical analysis comprised one-way analysis of variance (ANOVA) and post hoc tests. RESULTS: After synchronization, the typical pattern for clock genes was visible in control cells over the 24 h period. This pattern was significantly altered by mechanical strain. Under tensile stress, ARNTL gene expression was reduced, while Per1 and 2 gene expression were upregulated. In addition, mechanical stress had a differential effect on the expression of Col-1α and IL1­ß depending on its initiation within the circadian rhythm (group SI1 vs group SI2). For RUNX2, no significant differences in the two groups were observed. CONCLUSION: Our results suggest that mechanical stress affects the molecular peripheral oscillator of PDL cells. Vice versa, the circadian rhythm also seems to partially influence the effects that mechanical stress exerts on PDL cells.

Melatonin and Seasonal Synchrony in Mammals.

In mammals, seasonal opportunities and challenges are anticipated through programmed changes in physiology and behavior. Appropriate anticipatory timing depends on synchronization to the external solar year, achieved through the use of day length (photoperiod) as a synchronizing signal. In mammals, nocturnal production of melatonin by the pineal gland is the key hormonal mediator of photoperiodic change, exerting its effects via the hypothalamopituitary axis. In this review/perspective, we consider the key developments during the history of research into the seasonal synchronizer effect of melatonin, highlighting the role that the pars tuberalis-tanycyte module plays in this process. We go on to consider downstream pathways, which include discrete hypothalamic neuronal populations. Neurons that express the neuropeptides kisspeptin and (Arg)(Phe)-related peptide-3 (RFRP-3) govern seasonal reproductive function while neurons that express somatostatin may be involved in seasonal metabolic adaptations. Finally, we identify several outstanding questions, which need to be addressed to provide a much thorough understanding of the deep impact of melatonin upon seasonal synchronization.

Exploring the association between melatonin and nicotine dependence (Review).

Due to the addictive qualities of tobacco products and the compulsive craving and dependence associated with their use, nicotine dependence continues to be a serious public health concern on a global scale. Despite awareness of the associated health risks, nicotine addiction contributes to numerous acute and chronic medical conditions, including cardiovascular disease, respiratory disorders and cancer. The nocturnal secretion of pineal melatonin, known as the 'hormone of darkness', influences circadian rhythms and is implicated in addiction­related behaviors. Melatonin receptors are found throughout the brain, influencing dopaminergic neurotransmission and potentially attenuating nicotine­seeking behavior. Additionally, the antioxidant properties of melatonin may mitigate oxidative stress from chronic nicotine exposure, reducing cellular damage and lowering the risk of nicotine­related health issues. In addition to its effects on circadian rhythmicity, melatonin acting via specific neural receptors influences sleep and mood, and provides neuroprotection. Disruptions in melatonin signaling may contribute to sleep disturbances and mood disorders, highlighting the potential therapeutic role of melatonin in addiction and psychiatric conditions. Melatonin may influence neurotransmitter systems involved in addiction, such as the dopaminergic, glutamatergic, serotonergic and endogenous opioid systems. Preclinical studies suggest the potential of melatonin in modulating reward processing, attenuating drug­induced hyperactivity and reducing opioid withdrawal symptoms. Chronotherapeutic approaches targeting circadian rhythms and melatonin signaling show promise in smoking cessation interventions. Melatonin supplementation during periods of heightened nicotine cravings may alleviate withdrawal symptoms and reduce the reinforcing effects of nicotine. Further research is required however, to examine the molecular mechanisms underlying the melatonin­nicotine association and the optimization of therapeutic interventions. Challenges include variability in individual responses to melatonin, optimal dosing regimens and identifying biomarkers of treatment response. Understanding these complexities could lead to personalized treatment strategies and improve smoking cessation outcomes.

Prediction of lung adenocarcinoma prognosis and diagnosis with a novel model anchored in circadian clock-related genes.

Lung adenocarcinoma is the most common primary lung cancer seen in the world, and identifying genetic markers is essential for predicting the prognosis of lung adenocarcinoma and improving treatment outcomes. It is well known that alterations in circadian rhythms are associated with a higher risk of cancer. Moreover, circadian rhythms play a regulatory role in the human body. Therefore, studying the changes in circadian rhythms in cancer patients is crucial for optimizing treatment. The gene expression data and clinical data were sourced from TCGA database, and we identified the circadian clock-related genes. We used the obtained TCGA-LUAD data set to build the model, and the other 647 lung adenocarcinoma patients' data were collected from two GEO data sets for external verification. A risk score model for circadian clock-related genes was constructed, based on the identification of 8 genetically significant genes. Based on ROC analyses, the risk model demonstrated a high level of accuracy in predicting the overall survival times of lung adenocarcinoma patients in training folds, as well as external data sets. This study has successfully constructed a risk model for lung adenocarcinoma prognosis, utilizing circadian rhythm as its foundation. This model demonstrates a dependable capacity to forecast the outcome of the disease, which can further guide the relevant mechanism of lung adenocarcinoma and combine behavioral therapy with treatment to optimize treatment decision-making.

Circadian Rhythm and Nitrogen Metabolism Participate in the Response of Boron Deficiency in the Root of Brassica napus.

Boron (B) deficiency has been shown to inhibit root cell growth and division. However, the precise mechanism underlying B deficiency-mediated root tip growth inhibition remains unclear. In this study, we investigated the role of BnaA3.NIP5;1, a gene encoding a boric acid channel, in Brassica napus (B. napus). BnaA3.NIP5;1 is expressed in the lateral root cap and contributes to B acquisition in the root tip. Downregulation of BnaA3.NIP5;1 enhances B sensitivity in B. napus, resulting in reduced shoot biomass and impaired root tip development. Transcriptome analysis was conducted on root tips from wild-type B. napus (QY10) and BnaA3.NIP5;1 RNAi lines to assess the significance of B dynamics in meristematic cells during seedling growth. Differentially expressed genes (DEGs) were significantly enriched in plant circadian rhythm and nitrogen (N) metabolism pathways. Notably, the circadian-rhythm-related gene HY5 exhibited a similar B regulation pattern in Arabidopsis to that observed in B. napus. Furthermore, Arabidopsis mutants with disrupted circadian rhythm (hy5/cor27/toc1) displayed heightened sensitivity to low B compared to the wild type (Col-0). Consistent with expectations, B deficiency significantly disrupted N metabolism in B. napus roots, affecting nitrogen concentration, nitrate reductase enzyme activity, and glutamine synthesis. Interestingly, this disruption was exacerbated in BnaA3NIP5;1 RNAi lines. Overall, our findings highlight the critical role of B dynamics in root tip cells, impacting circadian rhythm and N metabolism, ultimately leading to retarded growth. This study provides novel insights into B regulation in root tip development and overall root growth in B. napus.

Effect of Alcohol on Clock Synchrony and Tissue Circadian Homeostasis in Mice.

Alcohol use disorder accounts for a growing worldwide health system concern. Alcohol causes damages to various organs, including intestine and liver, primarily involved in its absorption and metabolism. However, alcohol-related organ damage risk varies significantly among individuals, even when they report consuming comparable dosages of alcohol. Factor(s) that may modulate the risk of organ injuries from alcohol consumption could be responsible for inter-individual variations in susceptibility to alcohol-related organ damages. Accumulating evidence suggests disruptions in circadian rhythm can exacerbate alcohol-related organ damages. Here we investigated the interplay between alcohol, circadian rhythm, and key tissue cellular processes at baseline, after a regular and a shift in the light/dark cycle (LCD) in mice. Central/peripheral clock expression of core clock genes (CoClGs) was analyzed. We also studied circadian homeostasis of tissue cellular processes that are involved in damages from alcohol. These experiments reveal that alcohol affects the expression of CoClGs causing a central-peripheral dyssynchrony, amplified by shift in LCD. The observed circadian clock dyssynchrony was linked to circadian disorganization of key processes involved in the alcohol-related damages, particularly when alcohol was combined with LCD. These results offer insights into the mechanisms by which alcohol interacts with circadian rhythm disruption to promote organ injury.