Seizure timing and circadian patterns: a comprehensive bibliographic review / Cronometragem das crises epilépticas e padrões circadianos: uma revisão bibliográfica abrangente

Epilepsy's cyclic nature, increasingly quantified through advancements in continuous electroencephalography (cEEG), reveals robust seizure cycles including circadian, multidien, and circannual rhythms. Understanding these cycles' mechanisms and clinical implications, such as seizure forecasting and optimized treatment timing, is crucial. Despite historical observations, detailed analysis of seizure timing cycles has become feasible only recently, necessitating further research to confirm generalizability and clinical relevance. This paper reviews current literature on circadian rhythms in epilepsy, focusing on temporal seizure patterns and identifying knowledge gaps. A comprehensive review of studies, primarily using PubMed, synthesizes key findings from 20 studies on the temporal dynamics of epileptic activity. Research shows consistent circadian rhythms in seizure activity, with distinct daily peaks. Seizures often follow daily patterns, termed "seizure rush hours," with specific seizure types linked to particular times and influenced by sleep-wake cycles. These findings underscore the importance of understanding temporal patterns in epilepsy. Understanding these rhythms can enhance seizure prediction, diagnosis, and personalized treatment strategies. The significant role of biological rhythms suggests that tailored treatments based on individual circadian profiles could improve patient outcomes and quality of life. Further research is essential to elucidate the mechanisms driving these influences and validate findings across diverse cohorts.

A natureza cíclica da epilepsia, cada vez mais quantificada por meio dos avanços na eletroencefalografia contínua (cEEG), revela ciclos de crises epilépticas (CE) robustos, incluindo ritmos circadianos, multidiários e circanuais. Compreender os mecanismos e as implicações clínicas desses ciclos, como a previsão de CE e a otimização do momento do tratamento, é crucial. Apesar das observações históricas, a análise detalhada dos ciclos de tempo das CE tornou-se viável apenas recentemente, exigindo mais pesquisas para confirmar a generalização e a relevância clínica. Este artigo revisa a literatura atual sobre ritmos circadianos na epilepsia, focando nos padrões temporais das CE e identificando lacunas no conhecimento. Uma revisão abrangente dos estudos, principalmente utilizando o PubMed, sintetiza os principais achados de 20 estudos sobre a dinâmica temporal da atividade epiléptica. A pesquisa mostra ritmos circadianos consistentes na atividade das CE, com picos diários distintos. As CE frequentemente seguem padrões diários, denominados "horários de pico das convulsões" ("seizure rush hours"), com tipos específicos de CE vinculados a determinados horários e influenciados pelos ciclos sono-vigília. Esses achados destacam a importância de entender os padrões temporais na epilepsia. Compreender esses ritmos pode melhorar a previsão, o diagnóstico e as estratégias de tratamento personalizado das CE. O papel significativo dos ritmos biológicos sugere que tratamentos personalizados com base nos perfis circadianos individuais podem melhorar os resultados e a qualidade de vida dos pacientes. Mais pesquisas são essenciais para elucidar os mecanismos que impulsionam essas influências e validar os achados em diversas coortes.

Serial Home Blood Pressure and Heart Rate Measurements for Optimized Management.

BACKGROUND: Serial blood pressure and heart rate measurements, particularly obtained by the patients at home, are currently recommended for the management of patients. METHODS: Home blood pressure and heart rate measurements were obtained by an 81-year old husband and his 74-year old wife in the morning and evening, over the course of an entire month. RESULTS: Morning and evening systolic blood pressure (129.9 ± 5.5, 125.9 ± 10.2, respectively), and diastolic blood pressure (69.2 ± 4.0, 70.1 ± 5.3) were not different (P > .05), heart rate (61.2 ± 2.9, 69.0 ± 5.5) was higher in the evening (P = .00001) in the husband, while systolic blood pressure (134.7 ± 9.6, 119.0 ± 12.0) and diastolic blood pressure (78.6 ± 5.6, 72.1 ± 7.3) were higher in the morning (P = .00001, P = .00031), and heart rate (62.7 ± 4.7, 68.2 ± 4.6) was higher in the evening (P = .00017) in the wife. CONCLUSIONS: Patient-generated serial home blood pressure and heart rate logs provide essential data for the patients' management and could potentially be useful in research; circadian variation of blood pressure and heart rate calls for implementation of chronotherapeutic principles for the time of drug administration.

Impact of chrono-radiotherapy on the prognosis and treatment-related toxicity in patients with locally advanced nasopharyngeal carcinoma: A multicenter propensity-matched study.

The timing of radiotherapy (RT) delivery has been reported to affect both cancer survival and treatment toxicity. However, the association among the timing of RT delivery, survival, and toxicity in locally advanced nasopharyngeal carcinoma (LA-NPC) has not been investigated. We retrospectively reviewed patients diagnosed with LA-NPC who received definitive RT at multiple institutions. The median RT delivery daytime was categorized as morning (DAY) and night (NIGHT). Seasonal variations were classified into the darker half of the year (WINTER) and brighter half (SUMMER) according to the sunshine duration. Cohorts were balanced according to baseline characteristics using propensity score matching (PSM). Survival and toxicity outcomes were evaluated using Cox regression models. A total of 355 patients were included, with 194/161 in DAY/NIGHT and 187/168 in WINTER/SUMMER groups. RT delivered during the daytime prolonged the 5-year overall survival (OS) (90.6% vs. 80.0%, p = 0.009). However, the significance of the trend was lost after PSM (p = 0.068). After PSM analysis, the DAY cohort derived a greater benefit in 5-year progression-free survival (PFS) (85.6% vs. 73.4%, p = 0.021) and distant metastasis-free survival (DMFS) (89.2% vs. 80.8%, p = 0.051) in comparison with the NIGHT subgroup. Moreover, multivariate analysis showed that daytime RT was an independent prognostic factor for OS, PFS, and DMFS. Furthermore, daytime RT delivery was associated with an increase in the incidence of leukopenia and radiation dermatitis. RT delivery in SUMMER influenced only the OS significantly (before PSM: p = 0.051; after PSM: p = 0.034). There was no association between toxicity and the timing of RT delivery by season. In LA-NPC, the daytime of radical RT served as an independent prognostic factor. Furthermore, RT administered in the morning resulted in more severe toxic side effects than that at night, which needs to be confirmed in a future study.

Timely Questions Emerging in Chronobiology: The Circadian Clock Keeps on Ticking.

Chronobiology investigations have revealed much about cellular and physiological clockworks but we are far from having a complete mechanistic understanding of the physiological and ecological implications. Here we present some unresolved questions in circadian biology research as posed by the editorial staff and guest contributors to the Journal of Circadian Rhythms. This collection of ideas is not meant to be comprehensive but does reveal the breadth of our observations on emerging trends in chronobiology and circadian biology. It is amazing what could be achieved with various expected innovations in technologies, techniques, and mathematical tools that are being developed. We fully expect strengthening mechanistic work will be linked to health care and environmental understandings of circadian function. Now that most clock genes are known, linking these to physiological, metabolic, and developmental traits requires investigations from the single molecule to the terrestrial ecological scales. Real answers are expected for these questions over the next decade. Where are the circadian clocks at a cellular level? How are clocks coupled cellularly to generate organism level outcomes? How do communities of circadian organisms rhythmically interact with each other? In what way does the natural genetic variation in populations sculpt community behaviors? How will methods development for circadian research be used in disparate academic and commercial endeavors? These and other questions make it a very exciting time to be working as a chronobiologist.

Reflections on Several Landmark Advances in Circadian Biology.

Circadian Biology intersects with diverse scientific domains, intricately woven into the fabric of organismal physiology and behavior. The rhythmic orchestration of life by the circadian clock serves as a focal point for researchers across disciplines. This retrospective examination delves into several of the scientific milestones that have fundamentally shaped our contemporary understanding of circadian rhythms. From deciphering the complexities of clock genes at a cellular level to exploring the nuances of coupled oscillators in whole organism responses to stimuli. The field has undergone significant evolution lately guided by genetics approaches. Our exploration here considers key moments in the circadian-research landscape, elucidating the trajectory of this discipline with a keen eye on scientific advancements and paradigm shifts.

Brief Report: Clinical Outcomes by Infusion Timing of Immune Checkpoint Inhibitors in Patients With Locally Advanced NSCLC.

Introduction: Previous studies reported an association between immune checkpoint inhibitor infusion timing and the treatment effect in metastatic NSCLC. The present study assessed the association between durvalumab infusion timing and survival outcomes in patients with locally advanced NSCLC. Methods: Patients receiving durvalumab after chemoradiotherapy for locally advanced NSCLC at a single institution were retrospectively analyzed, and the association of the proportion of durvalumab infusions greater than or equal to 20% versus less than 20% after 3 PM with progression-free survival (PFS) and overall survival was assessed. Results: A total of 82 patients were included, with a median age of 69 years (interquartile range, 62-74 years); of these, 67 patients (82%) were of male sex, and 78 patients (95%) had a history of smoking. The median number of durvalumab infusions per patient was 16 (interquartile range, 8-24). Patients with at least 20% of their durvalumab infusions after 3 PM (n = 12/82, 15%) had a significantly shorter PFS than those who did not (median: 7.4 mo versus not available [NA]; hazard ratio [HR], 2.43; 95% confidence interval [CI]: 1.11-5.34, p = 0.027), whereas overall survival was shorter among the former compared with the latter group (median: 22.4 versus NA; HR, 1.80; 95% CI: 0.73-4.42, p = 0.20). In addition, both backward stepwise multivariable analysis and propensity score-matching analysis revealed that receiving at least 20% of durvalumab infusions after 3 PM was significantly associated with worse PFS (HR, 2.54; 95% CI: 1.03-5.67, p = 0.047; and HR, 4.64; 95% CI: 1.95-11.04; p < 0.001, respectively). Conclusions: The time of day of durvalumab infusions may impact survival outcomes in patients with locally advanced NSCLC.

Pioneering new frontiers in circadian medicine chronotherapies for cardiovascular health.

Cardiovascular disease (CVD) is a global health concern. Circadian medicine improves cardiovascular care by aligning treatments with our body's daily rhythms and their underlying cellular circadian mechanisms. Time-based therapies, or chronotherapies, show special promise in clinical cardiology. They optimize treatment schedules for better outcomes with fewer side effects by recognizing the profound influence of rhythmic body cycles. In this review, we focus on three chronotherapy areas (medication, light, and meal timing) with potential to enhance cardiovascular care. We also highlight pioneering research in the new field of rest, the gut microbiome, novel chronotherapies for hypertension, pain management, and small molecules that targeting the circadian mechanism.

Beyond Conventional Therapies: Molecular Dynamics of Alzheimer's Treatment through CLOCK/BMAL1 Interactions.

BACKGROUND: Alzheimer's Disease (AD) represents a neurodegenerative disorder characterized by cognitive and behavioral impairments significantly hindering social and occupational functioning. Melatonin, a hormone pivotal in regulating the body's intrinsic circadian rhythm, also acts as a catalyst in the breakdown of beta-amyloid deposits, offering a promising therapeutic approach for AD. The upregulation of Brain and Muscle ARNT-Like 1 (Bmal1) gene expression, stimulated by melatonin, emerges as a potential contributor to AD intervention. Current pharmacological interventions, such as FDA-approved cholinesterase inhibitors and the recently authorized monoclonal antibody, Lecanemab, are utilized in AD management. However, the connection between these medications and Bmal1 remains insufficiently explored. OBJECTIVE: This study aims to investigate the molecular effects of FDA-endorsed drugs on the CLOCK: Bmal1 dimer. Furthermore, considering the interactions between melatonin and Bmal1, this research explores the potential synergistic efficacy of combining these pharmaceutical agents with melatonin for AD treatment. METHODS: Using molecular docking and MM/PBSA methodologies, this research determines the binding affinities of drugs within the Bmal1 binding site, constructing interaction profiles. RESULTS: The findings reveal that, among FDA-approved drugs, galanthamine and donepezil demonstrate notably similar binding energy values to melatonin, interacting within the Bmal1 binding site through analogous amino acid residues and functional groups. CONCLUSION: A novel therapeutic approach emerges, suggesting the combination of melatonin with Lecanemab as a monoclonal antibody therapy. Importantly, prior research has not explored the effects of FDA-approved drugs on Bmal1 expression or their potential for synergistic effects.

Circadian Influences on Myocardial Ischemia-Reperfusion Injury and Heart Failure.

The impact of circadian rhythms on cardiovascular function and disease development is well established, with numerous studies in genetically modified animals emphasizing the circadian molecular clock's significance in the pathogenesis and pathophysiology of myocardial ischemia and heart failure progression. However, translational preclinical studies targeting the heart's circadian biology are just now emerging and are leading to the development of a novel field of medicine termed circadian medicine. In this review, we explore circadian molecular mechanisms and novel therapies, including (1) intense light, (2) small molecules modulating the circadian mechanism, and (3) chronotherapies such as cardiovascular drugs and meal timings. These promise significant clinical translation in circadian medicine for cardiovascular disease. (4) Additionally, we address the differential functioning of the circadian mechanism in males versus females, emphasizing the consideration of biological sex, gender, and aging in circadian therapies for cardiovascular disease.

Stroke in the Time of Circadian Medicine.

Time-of-day significantly influences the severity and incidence of stroke. Evidence has emerged not only for circadian governance over stroke risk factors, but also for important determinants of clinical outcome. In this review, we provide a comprehensive overview of the interplay between chronobiology and cerebrovascular disease. We discuss circadian regulation of pathophysiological mechanisms underlying stroke onset or tolerance as well as in vascular dementia. This includes cell death mechanisms, metabolism, mitochondrial function, and inflammation/immunity. Furthermore, we present clinical evidence supporting the link between disrupted circadian rhythms and increased susceptibility to stroke and dementia. We propose that circadian regulation of biochemical and physiological pathways in the brain increase susceptibility to damage after stroke in sleep and attenuate treatment effectiveness during the active phase. This review underscores the importance of considering circadian biology for understanding the pathology and treatment choice for stroke and vascular dementia and speculates that considering a patient's chronotype may be an important factor in developing precision treatment following stroke.

Long-term effects of environmental dynamic lighting on sleep-wake rhythm, mood and behaviour in older adults with intellectual disabilities.

BACKGROUND: Sleep-wake problems and depressive symptoms are common in people with intellectual disabilities (IDs) and are thought to be related to the unstable sleep-wake rhythm in this population. Previously, we showed that after increasing environmental light exposure, mid-sleep and sleep onset advanced, and mood improved over a period of 14 weeks after installing environmental dynamic light installations in the living room of people with IDs. We invited participants of that short-term study to take part in the current study on sleep-wake rhythm, mood and behaviour in older adults with IDs 1 year after installing environmental dynamic light installations in the common living rooms of six group homes. METHODS: A pre-post study was performed from October 2017 to February 2019. We included 45 participants (63.5 ± 8.5 years, 67% female) from six group home facilities who provided data at baseline (9, 4 and 1 weeks prior to installing light installations), short term (3, 7 and 14 weeks after installing light installations) and 1 year (54 weeks after installing light installations). Wrist activity was measured with actigraphy (GENEActiv) to derive the primary outcome of interdaily stability of sleep-wake rhythms as well as sleep estimates. Mood was measured with the Anxiety, Depression and Mood Scale. Behaviour was measured with the Aberrant Behaviour Checklist. RESULTS: One year after installing dynamic lighting, we did not find a change in interdaily stability. Total sleep time decreased (ß = -25.40 min; confidence interval: -10.99, -39.82), and sleep onset time was delayed (ß = 25.63 min; confidence interval: 11.18, 40.08). No effect on mood or behaviour was found. CONCLUSIONS: We did not find a change in sleep-wake rhythm, mood or behaviour in older persons with IDs living in care facilities 1 year after installing the light. We did find evidence for a long-term effect on sleep duration and sleep timing. The results have to be interpreted with care as the current study had a limited number of participants. The need for more research on the long-term effects of enhancing environmental light in ID settings is evident.

Circadian Rhythms of the Blood-Brain Barrier and Drug Delivery.

The blood-brain barrier (BBB) is a critical interface separating the central nervous system from the peripheral circulation, ensuring brain homeostasis and function. Recent research has unveiled a profound connection between the BBB and circadian rhythms, the endogenous oscillations synchronizing biological processes with the 24-hour light-dark cycle. This review explores the significance of circadian rhythms in the context of BBB functions, with an emphasis on substrate passage through the BBB. Our discussion includes efflux transporters and the molecular timing mechanisms that regulate their activities. A significant focus of this review is the potential implications of chronotherapy, leveraging our knowledge of circadian rhythms for improving drug delivery to the brain. Understanding the temporal changes in BBB can lead to optimized timing of drug administration, to enhance therapeutic efficacy for neurological disorders while reducing side effects. By elucidating the interplay between circadian rhythms and drug transport across the BBB, this review offers insights into innovative therapeutic interventions.

Chronodisruption and Gut Microbiota: Triggering Glycemic Imbalance in People with Type 2 Diabetes.

The desynchronization of physiological and behavioral mechanisms influences the gut microbiota and eating behavior in mammals, as shown in both rodents and humans, leading to the development of pathologies such as Type 2 diabetes (T2D), obesity, and metabolic syndrome. Recent studies propose resynchronization as a key input controlling metabolic cycles and contributing to reducing the risk of suffering some chronic diseases such as diabetes, obesity, or metabolic syndrome. In this analytical review, we present an overview of how desynchronization and its implications for the gut microbiome make people vulnerable to intestinal dysbiosis and consequent chronic diseases. In particular, we explore the eubiosis-dysbiosis phenomenon and, finally, propose some topics aimed at addressing chronotherapy as a key strategy in the prevention of chronic diseases.

Demonstrating the Benefits of Antihypertensive Nighttime Dosing and Indapamide Usage in Hypertension Management.

Background: Uncontrolled hypertension, specifically nocturnal hypertension, increases the risk for significant clinical outcomes. Evidence on the use of nighttime antihypertensives is scant and conflicting. In addition, hydrochlorothiazide continues to be the primary thiazide used despite being the least potent. Objective: The primary purpose of this study was to evaluate instituting nighttime dosing to control hypertension and compare the short-term effectiveness of blood pressure control with indapamide versus hydrochlorothiazide. Methods: This was a retrospective, observational study. Participant inclusion criteria consisted of patients 18 years of age or older, a current diagnosis of hypertension, and hypertension that required medical therapy. The investigator documented whether a patient was taking at least one antihypertensive at night versus all morning medications, as well as the use of indapamide versus hydrochlorothiazide. The patient's baseline and first follow-up blood pressure readings were documented. The primary outcome was to determine whether including nighttime dosing in antihypertensive regimens is more effective than all morning antihypertensive regimens. The secondary outcome was to determine whether indapamide was more effective than hydrochlorothiazide. Results: A total of 64 patients were included in the study. Twenty-eight patients were taking >1 nighttime antihypertensives versus 32 patients on all morning medications. Patients on at least one nighttime medication demonstrated greater systolic blood pressure reduction. There was no difference in blood pressure reduction between indapamide and hydrochlorothiazide. Conclusion: The study findings support the use of nighttime dosing to improve blood pressure management. The results on the effectiveness of indapamide versus hydrochlorothiazide conflict with previous research.

Just Let Me Sleep in: Identifying and Treating Delayed Sleep Phase Disorder in Adolescents.

Individuals with delayed sleep phase disorder (DSPD) are unable to naturally fall asleep and awake at conventional times; for this reason, DSPD is often mistaken for insomnia. However, unlike many patients with insomnia, those with DSPD struggle to get up at appropriate times. DSPD is associated with school refusal, academic difficulties, and lower employment rate. DSPD in youth has prevalence as high as 16%, and is often comorbid with other psychiatric disorders. Treatments include appropriate light exposure during the day, melatonin use, developing an evening routine that minimizes arousal-increasing activities, and gradually shifting sleep-wake times toward more functional ones.

Early morning immune checkpoint blockade and overall survival of patients with metastatic cancer: An In-depth chronotherapeutic study.

INTRODUCTION: Recent retrospective studies suggest potential large patient's benefit through proper timing of immune checkpoint blockers (ICB). The association between ICB treatment timing and patient survival, neoplastic response and toxicities was investigated, together with interactions with performance status (PS) and sex. METHODS: A cohort of patients with metastatic or locally advanced solid tumors, who received pembrolizumab, nivolumab, atezolizumab, durvalumab, or avelumab, alone or with concomitant chemotherapy, between November 2015 and March 2021, at the Centre Leon Bérard (France), was retrospectively studied. RESULTS: 361 patients were investigated (80% non-small cell lung cancer patients, mean [SD] age: 63 [11] years, 39% of women, 83% PS0-1 at first infusion, 19% received concomitant chemotherapy). ICB were administered from 07:25 to 17:21 and optimal morning/afternoon cut-off was 11:37. Morning infusions were associated with increased OS as compared to afternoon (median 30.3 vs 15.9 months, p = 0.0024; HR 1.56 [1.17-2.1], p = 0.003). A strong PS-timing interaction was found (PS0-1 patients, HR=1.53 [1.10-2.12], p = 0.011; PS2-3 patients, HR=0.50 [0.25-0.97], p = 0.042). Morning PS0-1 patients displayed increased OS (median 36.7 vs 21.3 months, p = 0.023), partial/complete response rate (58% vs 41%, p = 0.027), and grade1-3 toxicities (49% vs 34%, p = 0.028). Mortality risk ratio between infusions at worst time-of-day, estimated at 13:36 [12:48-14:23], and in early morning was equal to 4.8 ([2.3-10.1], p = 0.008). Timing differences in toxicities resulted significant only in female patients (women vs men: p < 0.001 vs 0.4). CONCLUSIONS: Early morning ICB infusion was associated with increased OS, response, and toxicities in patients with PS0-1 as compared to later infusions within the day. Prospective randomized trials are needed to confirm this retrospective study.

Effect of immunotherapy-infusion time of day on survival of patients with advanced cancers: a study-level meta-analysis.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have become the standard of care for numerous malignancies. Emerging evidence suggests that the time of day (ToD) of ICI administration could impact the outcomes of patients with cancer. The consistency of ToD effects on ICI efficacy awaits initial evaluation. MATERIALS AND METHODS: This meta-analysis integrates progression-free survival (PFS) and overall survival (OS) data from studies with a defined 'cut-off' ToD. Hazard ratios (HRs) [95% confidence interval (CI)] of an earlier progression or death according to 'early' or 'late' ToD of ICIs were collected from each report and pooled. RESULTS: Thirteen studies involved 1663 patients (Eastern Cooperative Oncology Group performance status 0-1, 83%; males/females, 67%/33%) with non-small-cell lung cancer (47%), renal cell carcinoma (24%), melanoma (20%), urothelial cancer (5%), or esophageal carcinoma (4%). Most patients received anti-programmed cell death protein 1 or anti-programmed death-ligand 1 (98%), and a small proportion also received anti-cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA-4) (18%). ToD cut-offs were 13:00 or 14:00 (i.e. ICI median infusion time), for six studies, and 16:00 or 16:30 (i.e. reported threshold for weaker vaccination responses) for seven studies. Pooled analyses revealed that the early ToD groups had longer OS (HR 0.50, 95% CI 0.42-0.58; P < 0.00001) and PFS (HR 0.51, 95% CI 0.42-0.61; P < 0.00001) compared with the late ToD groups. CONCLUSIONS: Patients with selected metastatic cancers seemed to largely benefit from early ToD ICI infusions, which is consistent with circadian mechanisms in immune-cell functions and trafficking. Prospective randomized trials are needed to establish recommendations for optimal circadian timing of ICI-based cancer therapies.

Circadian regulation of MGMT expression and promoter methylation underlies daily rhythms in TMZ sensitivity in glioblastoma.

BACKGROUND: Glioblastoma (GBM) is the most common primary brain tumor in adults. Despite extensive research and clinical trials, median survival post-treatment remains at 15 months. Thus, all opportunities to optimize current treatments and improve patient outcomes should be considered. A recent retrospective clinical study found that taking TMZ in the morning compared to the evening was associated with a 6-month increase in median survival in patients with MGMT-methylated GBM. Here, we hypothesized that TMZ efficacy depends on time-of-day and O6-Methylguanine-DNA Methyltransferase (MGMT) activity in murine and human models of GBM. METHODS AND RESULTS: In vitro recordings using real-time bioluminescence reporters revealed that GBM cells have intrinsic circadian rhythms in the expression of the core circadian clock genes Bmal1 and Per2, as well as in the DNA repair enzyme, MGMT. Independent measures of MGMT transcript levels and promoter methylation also showed daily rhythms intrinsic to GBM cells. These cells were more susceptible to TMZ when delivered at the daily peak of Bmal1 transcription. We found that in vivo morning administration of TMZ also decreased tumor size and increased body weight compared to evening drug delivery in mice bearing GBM xenografts. Finally, inhibition of MGMT activity with O6-Benzylguanine abrogated the daily rhythm in sensitivity to TMZ in vitro by increasing sensitivity at both the peak and trough of Bmal1 expression. CONCLUSION: We conclude that chemotherapy with TMZ can be dramatically enhanced by delivering at the daily maximum of tumor Bmal1 expression and minimum of MGMT activity and that scoring MGMT methylation status requires controlling for time of day of biopsy.

Clinical trial design for assessing hypertension medications: are critical circadian chronopharmacological principles being taking into account?

INTRODUCTION: Clinical hypertension trials typically rely on homeostatic principles, including single time-of-day office blood pressure (BP) measurements (OBPM), rather than circadian chronopharmacological principles, including ambulatory monitoring (ABPM) done around-the-clock to derive the asleep systolic BP (SBP) mean and sleep-time relative SBP decline - jointly the strongest prognosticators of cardiovascular disease (CVD) risk and true definition of hypertension - to qualify participants and assess outcomes. AREAS COVERED: Eight chronopharmacological elements are indispensable for design and conduct of hypertension medication trials, mainly those on ingestion-time differences in effects, and also a means of rating quality of investigations. Accordingly, we highlight the findings and shortcomings of: (i) 155 such ingestion-time trials, 83.9% finding at-bedtime/evening treatment more beneficial than conventional upon-awakening/morning treatment; (ii) HOPE and ONTARGET CVD outcomes investigations assessing in the former add-on ramipril at-bedtime and in the latter telmisartan, ramipril, or both in combination in the morning; and (iii) pragmatic TIME CVD outcomes trial. EXPERT OPINION: Failure to incorporate chronopharmacological principals - including ABPM to derive asleep SBP and SBP dipping to qualify subjects as hypertensive and assess CVD risk - results in deficient study design, dubious findings, and unnecessary medical controversy at the expense of advances in patient care.