Circadian Clock Gene bmal1 Acts as a Tumor Suppressor Gene in a Mice Model of Human Glioblastoma.

Glioblastomas derived from malignant astrocytes are the most common primary tumors of the central nervous system in humans, exhibiting very bad prognosis. Treatment with surgery, radiotherapy, and chemotherapy (mainly using temozolomide), generates as much one-year survival. The circadian clock controls different aspects of tumor development, and its role in GBM is beginning to be explored. Here, the role of the canonic circadian clock gene bmal1 was studied in vivo in a nude mice model bearing human GBMs from LN229 cells xenografted orthotopically in the dorsal striatum. For that aim, a bmal1 knock-down was generated in LN229 cells by CRISPR/Cas9 gene editing tool, and tumor progression was followed in male mice by measuring survival, tumor growth, cell proliferation and prognosis with CD44 marker, as well as astrocyte activation in the tumor microenvironment with GFAP and nestin markers. Disruption of bmal1 in the tumor decreased survival, increased tumor growth and CD44 expression, worsened motor performance, as well as increased GFAP expression in astrocytes at tumor microenvironment. In addition, survival and tumor progression was not affected in mice bearing LN229 wild type GBM that underwent circadian disruption by constant light, as compared to mice synchronized to 12:12 light-dark cycles. These results consistently demonstrate in an in vivo orthotopic model of human GBM, that bmal1 has a key role as a tumor suppressor gene regulating GBM progression.

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.

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.

Chronic circadian desynchronization of feeding-fasting rhythm generates alterations in daily glycemia, LDL cholesterolemia and microbiota composition in mice.

Introduction: The circadian system synchronizes behavior and physiology to the 24-h light- dark (LD) cycle. Timing of food intake and fasting periods provide strong signals for peripheral circadian clocks regulating nutrient assimilation, glucose, and lipid metabolism. Mice under 12 h light:12 h dark (LD) cycles exhibit behavioral activity and feeding during the dark period, while fasting occurs at rest during light. Disruption of energy metabolism, leading to an increase in body mass, was reported in experimental models of circadian desynchronization. In this work, the effects of chronic advances of the LD cycles (chronic jet-lag protocol, CJL) were studied on the daily homeostasis of energy metabolism and weight gain. Methods: Male C57 mice were subjected to a CJL or LD schedule, measuring IPGTT, insulinemia, microbiome composition and lipidemia. Results: Mice under CJL show behavioral desynchronization and feeding activity distributed similarly at the light and dark hours and, although feeding a similar daily amount of food as compared to controls, show an increase in weight gain. In addition, ad libitum glycemia rhythm was abolished in CJL-subjected mice, showing similar blood glucose values at light and dark. CJL also generated glucose intolerance at dark in an intraperitoneal glucose tolerance test (IPGTT), with increased insulin release at both light and dark periods. Low-density lipoprotein (LDL) cholesterolemia was increased under this condition, but no changes in HDL cholesterolemia were observed. Firmicutes/Bacteroidetes ratio was analyzed as a marker of circadian disruption of microbiota composition, showing opposite phases at the light and dark when comparing LD vs. CJL. Discussion: Chronic misalignment of feeding/fasting rhythm leads to metabolic disturbances generating nocturnal hyperglycemia, glucose intolerance and hyperinsulinemia in a IPGTT, increased LDL cholesterolemia, and increased weight gain, underscoring the importance of the timing of food consumption with respect to the circadian system for metabolic health.

Cysteine Oxidation Promotes Dimerization/Oligomerization of Circadian Protein Period 2.

The molecular circadian clock is based on a transcriptional/translational feedback loop in which the stability and half-life of circadian proteins is of importance. Cysteine residues of proteins are subject to several redox reactions leading to S-thiolation and disulfide bond formation, altering protein stability and function. In this work, the ability of the circadian protein period 2 (PER2) to undergo oxidation of cysteine thiols was investigated in HEK-293T cells. PER2 includes accessible cysteines susceptible to oxidation by nitroso cysteine (CysNO), altering its stability by decreasing its monomer form and subsequently increasing PER2 homodimers and multimers. These changes were reversed by treatment with 2-mercaptoethanol and partially mimicked by hydrogen peroxide. These results suggest that cysteine oxidation can prompt PER2 homodimer and multimer formation in vitro, likely by S-nitrosation and disulphide bond formation. These kinds of post-translational modifications of PER2 could be part of the redox regulation of the molecular circadian clock.

"CUIDARAS " : A Nominal and Personalized Health Care Model. Effectiveness of a Massive Screening for Colorectal Cancer Detection at Community level.

Health systems provides care only to those people who spontaneous demand for attention; excluding those who dont perceive illness or are not aware enough to consult. Alternative healthcare models based on the nominal-personalized care like "University Center for Integrated Care of Referred Health Care" (CUIDARAS) may have better results. In order to demonstrate benefits of this model, it was performed an experience based in colorectal cancer (CRC) detection and care that focused the entire population of the town. METHODS: It is an intervention study for early detection of CRC. A survey and a physical examination were performed in each adult from "CH" town. Two visits were made. Blood in stool test (BIST) was self-collected, analyzed and results delivered with appointment for a programmed video-colonoscopy (VCC) when test was positive. RESULTS: people enrolled (n546) had 59.9+/-6.4 yrs. Adherence was 93.8% of the target population; 99.2% performed BIST; while 95.3% a positive BIST had access to VCC and treatment. Overall cost of the experience (stool test, VCC, biopsy, local treatment) was 7685 USD, while costs associated to an advanced CRC classic treatment was USD 9577/patient (USD 26098 if treatment included bevacizumab). CONCLUSION: The present study based on preventive actions like blood in stool test, applied as a screening to all inhabitants in town, had 93.8% of adherence and high level of CRC early detection. A health model based on personalized care (CUIDARAS), achieved more effective results in terms health care and disease prevention, with a favorable benefit/cost ratio compared with classical health care provide by current system. Key words: Model of care; colorectal cancer; CUIDARAS; personalized care.

Acompañamiento Telefónico en Salud Mental, Consumos Problemáticos y Violencias. Co-visión: cuidar a los que cuidan / Transformation process of the Telephone Counseling and Support Service in Mental Health, Problematic Consumption and Violence. Joint vision: caring for those who care

El Servicio de Orientación y Acompañamiento Telefónico en Salud Mental, Consumos Problemáticos y Violencias en el ámbito de la salud pública en el marco de la Subsecretaría de Salud Mental PBA, integrado por trabajadores, profesionales y técnicos, cuya función se basa en la recepción de llamados telefónicos de los habitantes de la Provincia de Buenos Aires, con padecimiento relacionado a la Salud Mental, Consumos Problemáticos y Violencias. En la primera jornada describimos el proceso de transformación del Servicio concerniente a las prácticas en clave de derechos y ejes que nos propusimos como rectores de dicho proceso. En esta segunda oportunidad, el objetivo se relaciona con la puesta en común de los avances y obstáculos del dispositivo de "Co-visión" que estamos construyendo y atravesando colectivamente junto a la consolidación del equipo. La "Co-visión" se presenta como un proceso de acompañamiento para el equipo del Servicio en pos de promover la reflexividad en torno a las intervenciones que se llevan adelante. Consideramos que dicha metodología es plausible pensarla en perspectiva de "cuidar a quienes cuidan" como un espacio a construir para la atención y la escucha. Ello, se fundamenta en que muchas de las situaciones que requieren acompañamiento, derivación y orientación generan múltiples impactos en la subjetividad de los trabajadores que lo conforman. En relación a la construcción del equipo, nos encontramos con trabajadores de larga trayectoria habituados a las llamadas de carácter anónimo y con la finalidad de escucha focalizada en la derivación, enmarcada en prácticas que asociaban el consumo de sustancias con la inseguridad y con la salud individual. Trabajadores de la Red de Salud provenientes de otros espacios y nuevos/as profesionales con la primera experiencia de inserción en el Servicio. Nuevas demandas, orientaciones, acompañamientos para múltiples problemáticas que significaron y continúan representando la necesidad de generar un espacio democrático y de circulación de la palabra como el dispositivo de "co-visión"

Timing of Novel Drug 1A-116 to Circadian Rhythms Improves Therapeutic Effects against Glioblastoma.

The Ras homologous family of small guanosine triphosphate-binding enzymes (GTPases) is critical for cell migration and proliferation. The novel drug 1A-116 blocks the interaction site of the Ras-related C3 botulinum toxin substrate 1 (RAC1) GTPase with some of its guanine exchange factors (GEFs), such as T-cell lymphoma invasion and metastasis 1 (TIAM1), inhibiting cell motility and proliferation. Knowledge of circadian regulation of targets can improve chemotherapy in glioblastoma. Thus, circadian regulation in the efficacy of 1A-116 was studied in LN229 human glioblastoma cells and tumor-bearing nude mice. METHODS: Wild-type LN229 and BMAL1-deficient (i.e., lacking a functional circadian clock) LN229E1 cells were assessed for rhythms in TIAM1, BMAL1, and period circadian protein homolog 1 (PER1), as well as Tiam1, Bmal1, and Rac1 mRNA levels. The effects of 1A-116 on proliferation, apoptosis, and migration were then assessed upon applying the drug at different circadian times. Finally, 1A-116 was administered to tumor-bearing mice at two different circadian times. RESULTS: In LN229 cells, circadian oscillations were found for BMAL1, PER1, and TIAM1 (mRNA and protein), and for the effects of 1A-116 on proliferation, apoptosis, and migration, which were abolished in LN229E1 cells. Increased survival time was observed in tumor-bearing mice when treated with 1A-116 at the end of the light period (zeitgeber time 12, ZT12) compared either to animals treated at the beginning (ZT3) or with vehicle. CONCLUSIONS: These results unveil the circadian modulation in the efficacy of 1A-116, likely through RAC1 pathway rhythmicity, suggesting that a chronopharmacological approach is a feasible strategy to improve glioblastoma treatment.

Redox and Antioxidant Modulation of Circadian Rhythms: Effects of Nitroxyl, N-Acetylcysteine and Glutathione.

The circadian clock at the hypothalamic suprachiasmatic nucleus (SCN) entrains output rhythms to 24-h light cycles. To entrain by phase-advances, light signaling at the end of subjective night (circadian time 18, CT18) requires free radical nitric oxide (NO•) binding to soluble guanylate cyclase (sGC) heme group, activating the cyclic guanosine monophosphate (cGMP)-dependent protein kinase (PKG). Phase-delays at CT14 seem to be independent of NO•, whose redox-related species were yet to be investigated. Here, the one-electron reduction of NO• nitroxyl was pharmacologically delivered by Angeli's salt (AS) donor to assess its modulation on phase-resetting of locomotor rhythms in hamsters. Intracerebroventricular AS generated nitroxyl at the SCN, promoting phase-delays at CT14, but potentiated light-induced phase-advances at CT18. Glutathione/glutathione disulfide (GSH/GSSG) couple measured in SCN homogenates showed higher values at CT14 (i.e., more reduced) than at CT18 (oxidized). In addition, administration of antioxidants N-acetylcysteine (NAC) and GSH induced delays per se at CT14 but did not affect light-induced advances at CT18. Thus, the relative of NO• nitroxyl generates phase-delays in a reductive SCN environment, while an oxidative favors photic-advances. These data suggest that circadian phase-locking mechanisms should include redox SCN environment, generating relatives of NO•, as well as coupling with the molecular oscillator.

Role of G-Substrate in the NO/cGMP/PKG Signal Transduction Pathway for Photic Entrainment of the Hamster Circadian Clock.

The mammalian circadian clock at the hypothalamic suprachiasmatic nuclei (SCN) entrains biological rhythms to the 24-h cyclic environment, by encoding light-dark transitions in SCN neurons. Light pulses induce phase shifts in the clock and in circadian rhythms; photic signaling for circadian phase advances involves a nitric oxide (NO)/cyclic guanosine monophosphate (cGMP)/cGMP-dependent protein kinase (PKG) pathway, increasing the expression of Period (Per) genes. Effectors downstream of PKG remain unknown. Here we investigate the role of G-substrate (GS), a PKG substrate, in the hamster SCN. GS and phosphorylated G-substrate (p-GS) were present in a subset of SCN cells. Moreover, GS phosphorylation (p-GS/GS ratio) increased in SCN homogenates after light pulses delivered at circadian time (CT) 18 and intraperitoneal treatment with sildenafil, an inhibitor of phosphodiesterase 5 (a cGMP-specific phosphodiesterase). On the other hand, intracerebroventricular treatment with the PKG inhibitor KT5823, reduced photic phosphorylation of GS to basal levels. Since p-GS could act as a protein phosphatase 2 A (PP2A) inhibitor, we demonstrated physical interaction between p-GS and PP2A in SCN homogenates, and also a light-pulse dependent decrease of PP2A activity. Intracerebroventricular treatment with okadaic acid, a PP2A inhibitor, increased the magnitude of light-induced phase advances of locomotor rhythms. We provide evidence on the physiological phosphorylation of GS as a new downstream effector in the NO/cGMP/PKG photic pathway in the hamster SCN, including its role as a PP2A inhibitor.

Outcomes of a nine-month regimen for rifampicin-resistant tuberculosis up to 24 months after treatment completion in nine African countries.

BACKGROUND: Treatment outcomes of the shorter regimen for rifampicin-resistant tuberculosis are not completely established. We report on these outcomes two years after treatment completion among patients enrolled in an observational cohort study in nine African countries. METHODS: 1,006 patients treated with the nine-month regimen were followed every six months with sputum cultures up to 24 months after treatment completion. The risk of any unfavourable outcome, of failure and relapse, and of death during and after treatment was analysed according to patient's characteristics and initial drug susceptibility by Cox proportional hazard models. FINDINGS: Respectively 67.8% and 57.2% patients had >=1 culture result six months and 12 months after treatment completion. Fourteen relapses were diagnosed. The probability of relapse-free success was 79.3% (95% confidence interval [CI] 76.6-82.0%) overall, 80.9% (95% CI 78.0-84.0%) among HIV-negative and 72.5% (95% CI 66.5-78.9%) among HIV-infected patients. Initial fluoroquinolone (adjusted hazard ratio [aHR] 6.7 [95% CI 3.4-13.1]) and isoniazid resistance (aHR 9.4 [95% CI 1.3-68.0]) were significantly associated with increased risk of failure/relapse and of any unfavourable outcome. INTERPRETATION: The close to 80% relapse-free success indicates the good outcome of the regimen in low-and middle-income settings. Results confirm the lesser effectiveness of the regimen in patients with initial resistance to fluoroquinolones and support the use of high-dose isoniazid, but do not support exclusion of patients for resistance to drugs other than fluoroquinolones. FUNDING: Expertise-France and Agence Française de Développement.

Tuberculosis contact investigation and short-course preventive therapy among young children in Africa.

SETTING: The largest cities in Benin, Burkina Faso, Cameroon and Central African Republic.OBJECTIVE: To demonstrate the feasibility and document the effectiveness of household contact investigation and preventive therapy in resource-limited settings.DESIGN: Children under 5 years living at home with adults with bacteriologically confirmed pulmonary tuberculosis (TB) were screened using questionnaire, clinical examination, tuberculin skin test and chest X-ray. Children free of active TB were offered preventive treatment with a 3-month rifampicin-isoniazid (3RH) or 6-month isoniazid (6H) regimen in Benin. Children were followed-up monthly during treatment, then quarterly over 1 year. Costs of transportation, phone contacts and chest X-rays were covered.RESULTS: A total of 1965 children were enrolled, of whom 56 (2.8%) had prevalent TB at inclusion. Among the 1909 children free of TB, 1745 (91%) started preventive therapy, 1642 (94%) of whom completed treatment. Mild adverse reactions, mostly gastrointestinal, were reported in 2% of children. One case of incident TB, possibly due to a late TB infection, was reported after completing the 3RH regimen.CONCLUSION: Contact investigation and preventive therapy were successfully implemented in these resource-limited urban settings in programmatic conditions with few additional resources. The 3RH regimen is a valuable alternative to 6H for preventing TB.

World Health Organization 2018 treatment guidelines for rifampicin-resistant tuberculosis: uncertainty, potential risks and the way forward.

The 2018 World Health Organization (WHO) treatment guidelines for multidrug-/rifampicin-resistant tuberculosis (MDR/RR-TB) give preference to all-oral long regimens lasting for 18-20 months. The guidelines strongly recommend combining bedaquiline, levofloxacin (or moxifloxacin) and linezolid, supplemented by cycloserine and/or clofazimine. The effectiveness of this combination in a long regimen has not been tested in any study to date, with corresponding uncertainty. The guidelines indicate that, ideally, all MDR-TB patients should have - as a minimum - the isolate tested for fluoroquinolones, bedaquiline and linezolid susceptibility before the start of treatment. Unfortunately, the capacity for drug susceptibility testing is insufficient in resource-limited settings. The risk of acquired bedaquiline resistance cannot be ignored, especially in patients with undetected resistance to fluoroquinolones. Both linezolid and cycloserine are known for their high frequency of serious adverse events. The combination of bedaquiline, moxifloxacin and clofazimine in the same regimen may excessively increase the QT interval. These expected adverse effects are difficult to monitor and manage in resource-limited settings, and may result in frequent modifications and a less effective regimen. The final STREAM results have confirmed the non-inferiority of the short regimen compared with the long regimen. Before evidence on the all-oral long and modified all-oral short treatment regimens is available, the WHO-recommended short MDR-TB regimens, with monitoring for ototoxicity, remain a better treatment option for the management of MDR/RR-TB patients who are eligible for short regimens in low- and middle-income countries. National tuberculosis programmes should also strengthen their capacity in the detection and management of fluoroquinolone-resistant MDR-TB following the WHO guidelines.

Standardised shorter regimens versus individualised longer regimens for rifampin- or multidrug-resistant tuberculosis.

We sought to compare the effectiveness of two World Health Organization (WHO)-recommended regimens for the treatment of rifampin- or multidrug-resistant (RR/MDR) tuberculosis (TB): a standardised regimen of 9-12 months (the "shorter regimen") and individualised regimens of ≥20 months ("longer regimens").We collected individual patient data from observational studies identified through systematic reviews and a public call for data. We included patients meeting WHO eligibility criteria for the shorter regimen: not previously treated with second-line drugs, and with fluoroquinolone- and second-line injectable agent-susceptible RR/MDR-TB. We used propensity score matched, mixed effects meta-regression to calculate adjusted odds ratios and adjusted risk differences (aRDs) for failure or relapse, death within 12 months of treatment initiation and loss to follow-up.We included 2625 out of 3378 (77.7%) individuals from nine studies of shorter regimens and 2717 out of 13 104 (20.7%) individuals from 53 studies of longer regimens. Treatment success was higher with the shorter regimen than with longer regimens (pooled proportions 80.0% versus 75.3%), due to less loss to follow-up with the former (aRD -0.15, 95% CI -0.17- -0.12). The risk difference for failure or relapse was slightly higher with the shorter regimen overall (aRD 0.02, 95% CI 0-0.05) and greater in magnitude with baseline resistance to pyrazinamide (aRD 0.12, 95% CI 0.07-0.16), prothionamide/ethionamide (aRD 0.07, 95% CI -0.01-0.16) or ethambutol (aRD 0.09, 95% CI 0.04-0.13).In patients meeting WHO criteria for its use, the standardised shorter regimen was associated with substantially less loss to follow-up during treatment compared with individualised longer regimens and with more failure or relapse in the presence of resistance to component medications. Our findings support the need to improve access to reliable drug susceptibility testing.

Short-Course Regimen for Multidrug-Resistant Tuberculosis: A Decade of Evidence.

About ten years ago, the first results of the so-called "Bangladesh regimen", a short regimen lasting nine months instead of 20 months, revolutionized multidrug-resistant tuberculosis (MDR-TB) treatment. Similar short regimens were studied in different settings, relying for their efficacy on a later generation fluoroquinolone, either gatifloxacin, moxifloxacin, or levofloxacin. We review the published material on short MDR-TB regimens, describe their different compositions, their results in national tuberculosis programs in middle- and low-income countries, the risk of acquiring resistance to fluoroquinolone, and the occurrence of adverse events. With over 80% success, the regimen performs much better than longer regimens (usually around 50%). Monitoring of adverse events allows adapting its composition to prevent severe adverse events such as deafness. We discuss the current applicability and usefulness of the short injectable-containing regimen given the 2019 recommendation of the World Health Organization (WHO) for a new long all-oral regimen. We conclude that the most effective fluoroquinolone is gatifloxacin, currently not listed as an essential medicine by WHO. It is a priority to restore its status as an essential medicine.

Progress in global rollout of new multidrug-resistant tuberculosis treatments.

SETTING: The global multidrug-resistant tuberculosis (MDR-TB) epidemic has grown over the past decade and continues to be difficult to manage. In response, new drugs and treatment regimens have been recommended.OBJECTIVE: In 2017 and again in 2018, the International Union Against Tuberculosis and Lung Disease (The Union) drug-resistant (DR) TB Working Group collaborated with RESIST-TB to implement an internet survey to members of The Union around the world to assess access to these new treatment strategies.DESIGN: A nine-question survey was developed using SurveyMonkey®. The survey was open for participation to all members of The Union registered under the TB Section. Two reminders were sent during each survey. The responses were analyzed taking into account the WHO Region to which the respondent belonged.RESULTS: The 2018 survey showed a global increase in implementation of the shorter (9-month) MDR-TB regimen (from 33% to 56% of respondents, P < 0.001) and an increase in the use of bedaquiline and/or delamanid (from 25% to 41% of respondents, P < 0.001) compared to 2017. There were substantial variations in roll-out between WHO regions.CONCLUSION: These results demonstrate improvement in global implementation of the new treatment strategies over a 1-year period.