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2.
Plant Sci ; 311: 110992, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482906

RESUMO

Previous studies demonstrated that flower opening time (FOT) is a stable trait and precisely controlled by a circadian clock responsive to the environment. It plays a vital role in improving fertility. Hemerocallis spp. has different FOTs divided into two types: nocturnal and diurnal. To explore the regulatory mechanisms of their FOTs, we carried out a transcriptome sequencing experiment at different developmental stages of an F1 population with different FOTs. 55,883 unigenes were obtained, and 9234 differential genes were identified. Co-expression was analyzed by K-means clustering and weighted gene co-expression network analysis. Results showed that after entering reproductive growth, two FOT types of Hemerocallis had increased expression of genes related to photosynthetic metabolism and sensitivity to environmental response such as light and hormone signal transmission. Circadian rhythm-related activities were enriched in hub genes during the flowering stage. Genes showing differential expression between the two Hemerocallis groups were related to environmental response and photosynthesis pathways. Putative circadian clock genes displayed differences in expression across the flower opening stage in both groups of Hemerocallis. Twenty-three key circadian clock genes were identified, which related to sensitivity to light signal input and gating. These genes might closely relate to FOTs in Hemerocallis.


Assuntos
Relógios Circadianos/genética , Relógios Circadianos/fisiologia , Ritmo Circadiano/genética , Ritmo Circadiano/fisiologia , Flores/crescimento & desenvolvimento , Hemerocallis/genética , Hemerocallis/fisiologia , Adaptação Ocular , Escuridão , Flores/genética , Regulação da Expressão Gênica de Plantas , Fatores de Tempo
3.
Nutrients ; 13(7)2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34371807

RESUMO

The endocannabinoid system is involved in the regulation of a variety of physiological and cognitive processes. While the endocannabinoids 2-arachidonoylglycerol (2-AG) and anandamide (N-arachidonoylethanolamine, AEA) have been found in breast milk, their role(s) have yet to be determined. This study determined the normal concentration ranges of endocannabinoids (2-AG and AEA) in breast milk and the influences, if any, of obesity and diurnal rhythms on their levels. Milk samples were collected from 36 breastfeeding mothers at 4-8 weeks postpartum at each feed over a 24-h period, and further stratified into three groups based on body mass index (BMI). The samples were analyzed using liquid chromatography mass spectrometry. AEA was below the limit of detection and 2-AG levels averaged 59.3 ± 18.3 ng/mL (± SD) in women with normal BMI. Wide-ranging 2-AG concentrations in the overweight (65.5 ± 41.9 ng/mL) /obese (66.1 ± 40.6 ng/mL) groups suggest BMI may be a contributing factor influencing its levels. Following a diurnal pattern, there was a significantly higher 2-AG concentration observed during the day, as compared to night time samples. In conclusion, our study clearly suggests that appropriate milk collection and storage conditions are critical. Further, body weight and diurnal rhythm appear to influence levels of 2-AG. Based on these results, future studies are underway to determine what specific roles endocannabinoids may play in human milk and how elevated levels of 2-AG may modulate infant appetite and health.


Assuntos
Ácidos Araquidônicos/análise , Ritmo Circadiano/fisiologia , Endocanabinoides/análise , Glicerídeos/análise , Leite Humano/química , Obesidade/metabolismo , Alcamidas Poli-Insaturadas/análise , Adulto , Índice de Massa Corporal , Cromatografia Líquida , Feminino , Humanos , Estudos Longitudinais , Espectrometria de Massas , Fenômenos Fisiológicos da Nutrição Materna , Sobrepeso/fisiopatologia
4.
Nutrients ; 13(8)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34444685

RESUMO

Time-Restricted Eating is an eating pattern based on the circadian rhythm which limits daily food intake (usually to ≤12 h/day), unique in that no overt restriction is imposed on the quality, nor quantity, of food intake. This paper aimed to examine the effects of two patterns of TRE, traditional TRE, and Ramadan fasting, on two markers of circadian rhythm, cortisol and melatonin. PubMed and Web of Science were searched up to December 2020 for studies examining the effects of time restricted eating on cortisol and melatonin. Fourteen studies met our inclusion criteria. All Ramadan papers found statistically significant decrease in melatonin (p < 0.05) during Ramadan. Two out of the three Ramadan papers noted an abolishing of the circadian rhythm of cortisol (p < 0.05). The non-Ramadan TRE papers did not examine melatonin, and cortisol changes were mixed. In studies comparing TRE to control diets, Stratton et al. found increased cortisol levels in the non-TRE fasting group (p = 0.0018) and McAllister et al. noted no difference. Dinner-skipping resulted in significantly reduced evening cortisol and non-significantly raised morning cortisol. Conversely, breakfast skipping resulted in significantly reduced morning cortisol. This blunting indicates a dysfunctional HPA axis, and may be associated with poor cardio-metabolic outcomes. There is a paucity of research examining the effects of TRE on cortisol and melatonin. The contrasting effect of dinner and breakfast-skipping should be further examined to ascertain whether timing the feeding window indeed has an impact on circadian rhythmicity.


Assuntos
Ritmo Circadiano/fisiologia , Jejum/fisiologia , Comportamento Alimentar/fisiologia , Hidrocortisona/sangue , Melatonina/sangue , Fenômenos Fisiológicos da Nutrição/fisiologia , Adulto , Desjejum/fisiologia , Feminino , Humanos , Masculino , Refeições/fisiologia , Pessoa de Meia-Idade , Religião , Fatores de Tempo
5.
FASEB J ; 35(9): e21802, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34383984

RESUMO

Mutations in transcription factors often exhibit pleiotropic effects related to their complex expression patterns and multiple regulatory targets. One such mutation in the zinc finger homeobox 3 (ZFHX3) transcription factor, short circuit (Sci, Zfhx3Sci/+ ), is associated with significant circadian deficits in mice. However, given evidence of its retinal expression, we set out to establish the effects of the mutation on retinal function using molecular, cellular, behavioral and electrophysiological measures. Immunohistochemistry confirms the expression of ZFHX3 in multiple retinal cell types, including GABAergic amacrine cells and retinal ganglion cells including intrinsically photosensitive retinal ganglion cells (ipRGCs). Zfhx3Sci/+ mutants display reduced light responsiveness in locomotor activity and circadian entrainment, relatively normal electroretinogram and optomotor responses but exhibit an unexpected pupillary reflex phenotype with markedly increased sensitivity. Furthermore, multiple electrode array recordings of Zfhx3Sci/+ retina show an increased sensitivity of ipRGC light responses.


Assuntos
Ritmo Circadiano/fisiologia , Proteínas de Homeodomínio/metabolismo , Retina/metabolismo , Células Amácrinas/metabolismo , Animais , Luz , Locomoção/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estimulação Luminosa/métodos , Células Ganglionares da Retina/metabolismo , Visão Ocular/fisiologia
6.
Nat Plants ; 7(9): 1314-1322, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34462576

RESUMO

Photosynthesis in deserts is challenging since it requires fast adaptation to rapid night-to-day changes, that is, from dawn's low light (LL) to extreme high light (HL) intensities during the daytime. To understand these adaptation mechanisms, we purified photosystem I (PSI) from Chlorella ohadii, a green alga that was isolated from a desert soil crust, and identified the essential functional and structural changes that enable the photosystem to perform photosynthesis under extreme high light conditions. The cryo-electron microscopy structures of PSI from cells grown under low light (PSILL) and high light (PSIHL), obtained at 2.70 and 2.71 Å, respectively, show that part of light-harvesting antenna complex I (LHCI) and the core complex subunit (PsaO) are eliminated from PSIHL to minimize the photodamage. An additional change is in the pigment composition and their number in LHCIHL; about 50% of chlorophyll b is replaced by chlorophyll a. This leads to higher electron transfer rates in PSIHL and might enable C. ohadii PSI to act as a natural photosynthesiser in photobiocatalytic systems. PSIHL or PSILL were attached to an electrode and their induced photocurrent was determined. To obtain photocurrents comparable with PSIHL, 25 times the amount of PSILL was required, demonstrating the high efficiency of PSIHL. Hence, we suggest that C. ohadii PSIHL is an ideal candidate for the design of desert artificial photobiocatalytic systems.


Assuntos
Adaptação Ocular/fisiologia , Proliferação de Células/fisiologia , Chlorella/metabolismo , Chlorella/ultraestrutura , Ritmo Circadiano/fisiologia , Temperatura Alta , Complexo de Proteína do Fotossistema I/metabolismo
7.
Nat Commun ; 12(1): 4672, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344864

RESUMO

Circadian rhythms have natural relative variations among humans known as chronotype. Chronotype or being a morning or evening person, has a specific physiological, behavioural, and also genetic manifestation. Whether and how chronotype modulates human brain physiology and cognition is, however, not well understood. Here we examine how cortical excitability, neuroplasticity, and cognition are associated with chronotype in early and late chronotype individuals. We monitor motor cortical excitability, brain stimulation-induced neuroplasticity, and examine motor learning and cognitive functions at circadian-preferred and non-preferred times of day in 32 individuals. Motor learning and cognitive performance (working memory, and attention) along with their electrophysiological components are significantly enhanced at the circadian-preferred, compared to the non-preferred time. This outperformance is associated with enhanced cortical excitability (prominent cortical facilitation, diminished cortical inhibition), and long-term potentiation/depression-like plasticity. Our data show convergent findings of how chronotype can modulate human brain functions from basic physiological mechanisms to behaviour and higher-order cognition.


Assuntos
Encéfalo/fisiologia , Ritmo Circadiano/fisiologia , Cognição/fisiologia , Adulto , Atenção/fisiologia , Comportamento/fisiologia , Excitabilidade Cortical , Feminino , Humanos , Aprendizagem/fisiologia , Masculino , Memória de Curto Prazo/fisiologia , Plasticidade Neuronal , Sono/fisiologia , Estimulação Magnética Transcraniana , Adulto Jovem
8.
Nutrients ; 13(7)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34371977

RESUMO

The effectiveness of weight loss treatment displays dramatic inter-individual variabilities, even with well-controlled energy intake/expenditure. This study aimed to determine the association between daily rhythms of cardiac autonomic control and weight loss efficiency and to explore the potential relevance to weight loss resistance in humans carrying the genetic variant C at CLOCK 3111T/C. A total of 39 overweight/obese Caucasian women (20 CLOCK 3111C carriers and 19 non-carriers) completed a behaviour-dietary obesity treatment of ~20 weeks, during which body weight was assessed weekly. Ambulatory electrocardiographic data were continuously collected for up to 3.5 days and used to quantify the daily rhythm of fractal cardiac dynamics (FCD), a non-linear measure of autonomic function. FCD showed a 24 h rhythm (p < 0.001). Independent of energy intake and physical activity level, faster weight loss was observed in individuals with the phase (peak) of the rhythm between ~2-8 p.m. and with a larger amplitude. Interestingly, the phase effect was significant only in C carriers (p = 0.008), while the amplitude effect was only significant in TT carriers (p < 0.0001). The daily rhythm of FCD and CLOCK 3111T/C genotype is linked to weight loss response interactively, suggesting complex interactions between the genetics of the circadian clock, the daily rhythm of autonomic control, and energy balance control.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Proteínas CLOCK/genética , Ritmo Circadiano/genética , Coração/inervação , Sobrepeso/terapia , Perda de Peso/genética , Adulto , Estudos de Casos e Controles , Ritmo Circadiano/fisiologia , Eletrocardiografia Ambulatorial , Ingestão de Energia , Exercício Físico , Feminino , Fractais , Genótipo , Coração/fisiopatologia , Humanos , Pessoa de Meia-Idade , Obesidade/genética , Obesidade/fisiopatologia , Obesidade/terapia , Sobrepeso/genética , Sobrepeso/fisiopatologia , Polimorfismo de Nucleotídeo Único/genética
9.
Nat Plants ; 7(7): 877-887, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34211130

RESUMO

Diurnal cycling of plant carbon uptake and water use, and their responses to water and heat stresses, provide direct insight into assessing ecosystem productivity, agricultural production and management practices, carbon and water cycles, and feedbacks to the climate. Temperature, light, atmospheric water demand, soil moisture and leaf water potential vary over the course of the day, leading to diurnal variations in stomatal conductance, photosynthesis and transpiration. Earth observations from polar-orbiting satellites are incapable of studying these diurnal variations. Here, we review the emerging satellite observations that have the potential for studying how plant functioning and ecosystem processes vary over the course of the diurnal cycle. The recently launched ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) and Orbiting Carbon Observatory-3 (OCO-3) provide land surface temperature, evapotranspiration (ET), gross primary production (GPP) and solar-induced chlorophyll fluorescence data at different times of day. New generation operational geostationary satellites such as Himawari-8 and the GOES-R series can provide continuous, high-frequency data of land surface temperature, solar radiation, GPP and ET. Future satellite missions such as GeoCarb, TEMPO and Sentinel-4 are also planned to have diurnal sampling capability of solar-induced chlorophyll fluorescence. We explore the unprecedented opportunities for characterizing and understanding how GPP, ET and water use efficiency vary over the course of the day in response to temperature and water stresses, and management practices. We also envision that these emerging observations will revolutionize studies of plant functioning and ecosystem processes in the context of climate change and that these observations and findings can inform agricultural and forest management and lead to improvements in Earth system models and climate projections.


Assuntos
Ritmo Circadiano/fisiologia , Ecossistema , Monitoramento Ambiental/métodos , Desenvolvimento Vegetal/fisiologia , Tecnologia de Sensoriamento Remoto
10.
Eur J Endocrinol ; 185(4): K1-K6, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34324429

RESUMO

Background: Many hormones display distinct circadian rhythms, driven by central regulators, hormonal bioavailability, and half-life. A set of 11-oxygenated C19 steroids (11-oxyandrogens) and pregnenolone sulfate (PregS) are elevated in congenital adrenal hyperplasia and other disorders, but their circadian patterns have not been characterized. Participants and methods: Peripheral blood was collected every 2 h over 24 h from healthy volunteer men (10 young, 18-30 years, and 10 older, 60-80 years). We used mass spectrometry to quantify 15 steroids, including androstenedione (A4), testosterone (T), 11ß-hydroxy- and 11-ketotestosterone (11OHT, 11KT),11ß-hydroxy- and 11-ketoandrostenedione (11OHA4, 11KA4), and 4 ∆5-steroid sulfates. Diurnal models including mesor (rhythm adjusted median), peak, and nadir concentrations, acrophase, and amplitude were computed. Results: 11OHA4 followed a rhythm similar to cortisol: acrophase 8:00 h, nadir 21:00 h and were similar in young and old men. 11KT had similar diurnal patterns, but the peak was lower in older than in young men, as was the case for A4. All four steroid sulfates were higher in young vs older men. PregS and 17-hydroxypregnenolone sulfate (17OHPregS) showed sustained elevations between 8:00 and 18:00 h, and nadirs around midnight, while DHEAS and AdiolS displayed minimal diurnal variations. All 4 11-oxyandrogens correlated tightly with cortisol (r from 0.54 for 11OHT to 0.81 for 11OHA4, P < 0.0001 for all), but very weakly with T, supporting their adrenal origin and ACTH governance. Conclusions: 11-Oxyandrogens, PregS, and 17OHPregS display distinct circadian and age variations, which should be accounted for when used as clinical biomarkers.


Assuntos
Androgênios/sangue , Ritmo Circadiano/fisiologia , Sulfatos/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Androgênios/química , Análise Química do Sangue/métodos , Voluntários Saudáveis , Humanos , Hidroxiesteroides/sangue , Cetosteroides/sangue , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Adulto Jovem
11.
Biomolecules ; 11(6)2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34207942

RESUMO

Blood pressure (BP) follows a circadian rhythm, it increases on waking in the morning and decreases during sleeping at night. Disruption of the circadian BP rhythm has been reported to be associated with worsened cardiovascular and renal outcomes, however the underlying molecular mechanisms are still not clear. In this review, we briefly summarized the current understanding of the circadian BP regulation and provided therapeutic overview of the relationship between circadian BP rhythm and cardiovascular and renal health and disease.


Assuntos
Pressão Sanguínea/fisiologia , Doenças Cardiovasculares/fisiopatologia , Ritmo Circadiano/fisiologia , Nefropatias/fisiopatologia , Doenças Cardiovasculares/metabolismo , Sistema Cardiovascular/fisiopatologia , China , Humanos , Hipertensão/fisiopatologia , Rim/fisiopatologia , Nefropatias/metabolismo
12.
Int J Mol Sci ; 22(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202781

RESUMO

Breastfeeding protects against adverse cardiovascular outcomes in the long term. Melatonin is an active molecule that is present in the breast milk produced at night beginning in the first stages of lactation. This indoleamine appears to be a relevant contributor to the benefits of breast milk because it can affect infant health in several ways. The melatonin concentration in breast milk varies in a circadian pattern, making breast milk a chrononutrient. The consumption of melatonin can induce the first circadian stimulation in the infant's body at an age when his/her own circadian machinery is not functioning yet. This molecule is also a powerful antioxidant with the ability to act on infant cells directly as a scavenger and indirectly by lowering oxidant molecule production and enhancing the antioxidant capacity of the body. Melatonin also participates in regulating inflammation. Furthermore, melatonin can participate in shaping the gut microbiota composition, richness, and variation over time, also modulating which molecules are absorbed by the host. In all these ways, melatonin from breast milk influences weight gain in infants, limiting the development of obesity and comorbidities in the long term, and it can help shape the ideal cellular environment for the development of the infant's cardiovascular system.


Assuntos
Sistema Cardiovascular/metabolismo , Melatonina/metabolismo , Fenômenos Fisiológicos da Nutrição , Animais , Aleitamento Materno , Sistema Cardiovascular/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Suscetibilidade a Doenças , Microbioma Gastrointestinal , Humanos , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Lactação , Melatonina/farmacologia , Redes e Vias Metabólicas , Estresse Oxidativo/efeitos dos fármacos
13.
Nutrients ; 13(7)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209002

RESUMO

Chronotype (CT) has been associated with predisposition to chronic noncommunicable diseases (CNCDs), such as diabetes mellitus and obesity. However, the effects of CT on individuals assisted by public health systems (PHSs) in middle-up economies are still poorly explored. The objective of this study was to evaluate the relationship between CT and clinical, sociobehavioral and nutritional aspects in adults assisted by a PHS in Brazil. This is a population-based cross-sectional study. The sample consisted of 380 individuals, selected through probabilistic sampling by clusters, in all health units in a city of approximately 100 thousand inhabitants. Data collection was performed during home visits, by means of general and nutritional interviews, anthropometric measurements and the Morningness-Eveningness Questionnaire (MEQ). Statistical analysis comprised chi-square test and principal component analysis (CPA) followed by Fisher's discriminant analysis to determine aspects associated with each CT (morning, evening or intermediate). With the aim of explaining the variation in the CT scores, the consumption of micronutrients (corrected to the total energy intake) and other individual and sociodemographic variables were used as explanatory factors in the adjustment of a linear regression model. The morning group was characterized by older men, with less than eight years of schooling, with low body mass index (BMI) and with low intake of omega-6, omega-3, sodium, zinc, thiamine, pyridoxine and niacin. The evening group, on the other hand, was composed of younger individuals, with a high consumption of these same nutrients, with high BMI and a higher frequency of heart diseases (p < 0.05). It was concluded that most morning CT individuals were elderly thin males with lower consumption of omega-6 and -3, sodium, zinc, thiamine, pyridoxine and niacin, whereas evening individuals were younger, had higher BMI and had higher consumption of the studied micronutrients. The identification of circadian and behavioral risk groups can help to provide preventive and multidisciplinary health promotion measures.


Assuntos
Ritmo Circadiano/fisiologia , Atenção à Saúde , Fenômenos Fisiológicos da Nutrição , Saúde Pública , Comportamento Social , Adulto , Brasil , Feminino , Humanos , Masculino , Micronutrientes/análise , Análise de Componente Principal
14.
Sleep Med Clin ; 16(3): 523-531, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34325828

RESUMO

The original rationale for the adoption of daylight saving time (DST) was to conserve energy; however, the effects of DST on energy consumption are questionable or negligible. Conversely, there is substantial evidence that DST transitions have the cumulative effect on sleep deprivation with its adverse health effects. In light of current evidence, the European Commission in 2018 decided that biannual clock change in Europe would be abolished. Current indirect evidence supports the adoption of perennial standard time, which aligns best with the human circadian system and has the potential to produce benefits for public health and safety.


Assuntos
Ritmo Circadiano , Fotoperíodo , Privação do Sono , Tempo , Ritmo Circadiano/fisiologia , Humanos , Privação do Sono/epidemiologia
15.
Nat Metab ; 3(6): 829-842, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34059820

RESUMO

The mammalian circadian system consists of a central clock in the brain that synchronizes clocks in the peripheral tissues. Although the hierarchy between central and peripheral clocks is established, little is known regarding the specificity and functional organization of peripheral clocks. Here, we employ altered feeding paradigms in conjunction with liver-clock mutant mice to map disparities and interactions between peripheral rhythms. We find that peripheral clocks largely differ in their responses to feeding time. Disruption of the liver-clock, despite its prominent role in nutrient processing, does not affect the rhythmicity of clocks in other peripheral tissues. Yet, unexpectedly, liver-clock disruption strongly modulates the transcriptional rhythmicity of peripheral tissues, primarily on daytime feeding. Concomitantly, liver-clock mutant mice exhibit impaired glucose and lipid homeostasis, which are aggravated by daytime feeding. Overall, our findings suggest that, upon nutrient challenge, the liver-clock buffers the effect of feeding-related signals on rhythmicity of peripheral tissues, irrespective of their clocks.


Assuntos
Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Ingestão de Energia , Fígado/fisiologia , Animais , Encéfalo/fisiologia , Metabolismo Energético , Comportamento Alimentar , Regulação da Expressão Gênica , Glucose/metabolismo , Metabolismo dos Lipídeos , Camundongos , Mutação , Especificidade de Órgãos , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Transdução de Sinais
16.
J Alzheimers Dis ; 82(3): 899-904, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34120906

RESUMO

Diurnal salivary cortisol was measured in 334 older adults without dementia, at four times on two separate days, under quiet and stressful conditions. In multivariate Cox proportional hazard models, higher global diurnal cortisol secretion was associated with incident dementia (HR = 1.09 [1.02-1.15] per one-unit increase in cortisol measure, p = 0.007) and Alzheimer's disease (HR = 1.12 [1.04-1.21], p = 0.003) over a mean (SD) of 8.1 (4.0) years, independent of potential confounders and stressful conditions. Individuals with incident dementia had a slower rate of cortisol elimination under non-stressful conditions, reflected by higher cortisol levels in the evening, and an abnormal response to stress (blunted evening stress response).


Assuntos
Ritmo Circadiano/fisiologia , Demência/metabolismo , Demência/psicologia , Hidrocortisona/metabolismo , Achados Incidentais , Vida Independente/psicologia , Idoso , Idoso de 80 Anos ou mais , Demência/diagnóstico , Feminino , Seguimentos , Humanos , Hidrocortisona/análise , Vida Independente/tendências , Masculino , Sintomas Prodrômicos , Estudos Prospectivos , Saliva/química , Saliva/metabolismo , Estresse Psicológico/diagnóstico , Estresse Psicológico/metabolismo , Estresse Psicológico/psicologia
17.
Nat Commun ; 12(1): 3482, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108488

RESUMO

Hyperplastic expansion of white adipose tissue (WAT) relies in part on the proliferation of adipocyte precursor cells residing in the stromal vascular cell fraction (SVF) of WAT. This study reveals a circadian clock- and feeding-induced diurnal pattern of cell proliferation in the SVF of visceral and subcutaneous WAT in vivo, with higher proliferation of visceral adipocyte progenitor cells subsequent to feeding in lean mice. Fasting or loss of rhythmic feeding eliminates this diurnal proliferation, while high fat feeding or genetic disruption of the molecular circadian clock modifies the temporal expression of proliferation genes and impinges on diurnal SVF proliferation in eWAT. Surprisingly, high fat diet reversal, sufficient to reverse elevated SVF proliferation in eWAT, was insufficient in restoring diurnal patterns of SVF proliferation, suggesting that high fat diet induces a sustained disruption of the adipose circadian clock. In conclusion, the circadian clock and feeding simultaneously impart dynamic, regulatory control of adipocyte progenitor proliferation, which may be a critical determinant of adipose tissue expansion and health over time.


Assuntos
Tecido Adiposo Branco/citologia , Proliferação de Células , Ritmo Circadiano/fisiologia , Adipócitos/citologia , Animais , Proliferação de Células/genética , Relógios Circadianos/genética , Relógios Circadianos/fisiologia , Ritmo Circadiano/genética , Dieta Hiperlipídica , Epididimo/citologia , Jejum , Humanos , Masculino , Camundongos , Células Estromais/citologia , Gordura Subcutânea/citologia , Gordura Subcutânea/fisiologia
18.
Am J Physiol Renal Physiol ; 321(2): F195-F206, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34151591

RESUMO

The spontaneously hypertensive rat (SHR), a genetic model of high blood pressure, has also been studied as a potential model of overactive bladder. In vivo studies have confirmed the presence of surrogate markers of overactive bladder, including detrusor overactivity, increased urinary frequency, decreased bladder capacity and voided volume (VV), and afferent hypersensitivity to bladder irritation. However, these observations were during awake cystometry using implanted bladder catheters tethered to an infusion pump and artificially filled. We conducted experiments in awake unrestrained untethered age-matched female SHRs and Wistar rats to quantify naïve consumption and voiding behavior and the effect of capsaicin desensitization on consumption and voiding behavior. Food and water consumption, body weight, voiding frequency, and VV were recorded. Rats were placed in metabolism cages for 24 h, up to twice a week, from 17 to 37 wk of age. Compared with Wistar rats, SHRs exhibited decrease in VV and did not exhibit diurnal variation in VV between light and dark periods, suggesting that SHRs may have bladder hypersensitivity. Furthermore, SHRs may also have smaller bladder capacities, as they consumed less water, voided less volume (regardless of light cycle), and had equal urinary frequencies compared with age-matched Wistar rats. We detected no change in SHR voiding behavior following capsaicin desensitization, which was in contrast to a prior awake in vivo cystometry study describing increased VV and micturition interval in SHRs and suggests that C-fiber activity may not contribute to bladder hypersensitivity in SHRs.NEW & NOTEWORTHY We characterized the long-term (20 wk) voiding, defecation, and consumption behavior of age-matched spontaneously hypertensive and Wistar rats without the influence of anesthesia or catheters. Spontaneously hypertensive rats exhibited bladder hypersensitiviy that persisted for the 20-wk duration and was unaffected by capsacin desensitization.


Assuntos
Ritmo Circadiano/fisiologia , Hipertensão/fisiopatologia , Bexiga Urinária Hiperativa/fisiopatologia , Micção/fisiologia , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Capsaicina/farmacologia , Ritmo Circadiano/efeitos dos fármacos , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Líquidos/fisiologia , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Micção/efeitos dos fármacos
19.
FASEB J ; 35(7): e21722, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34160105

RESUMO

Retinal photoreceptors undergo daily renewal of their distal outer segments, a process indispensable for maintaining retinal health. Photoreceptor outer segment (POS) phagocytosis occurs as a daily peak, roughly about 1 hour after light onset. However, the underlying cellular and molecular mechanisms which initiate this process are still unknown. Here we show that, under constant darkness, mice deficient for core circadian clock genes (Per1 and Per2) lack a daily peak in POS phagocytosis. By qPCR analysis, we found that core clock genes were rhythmic over 24 hours in both WT and Per1, Per2 double mutant whole retinas. More precise transcriptomics analysis of laser capture microdissected WT photoreceptors revealed no differentially expressed genes between time points preceding and during the peak of POS phagocytosis. In contrast, we found that microdissected WT retinal pigment epithelium (RPE) had a number of genes that were differentially expressed at the peak phagocytic time point compared to adjacent ones. We also found a number of differentially expressed genes in Per1, Per2 double mutant RPE compared to WT ones at the peak phagocytic time point. Finally, based on STRING analysis, we found a group of interacting genes that potentially drive POS phagocytosis in the RPE. This potential pathway consists of genes such as: Pacsin1, Syp, Camk2b, and Camk2d among others. Our findings indicate that Per1 and Per2 are necessary clock components for driving POS phagocytosis and suggest that this process is transcriptionally driven by the RPE.


Assuntos
Relógios Circadianos/genética , Ritmo Circadiano/genética , Proteínas Circadianas Period/genética , Fagocitose/genética , Células Fotorreceptoras de Vertebrados/fisiologia , Retina/fisiologia , Animais , Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fagocitose/fisiologia , Células Fotorreceptoras/fisiologia , Epitélio Pigmentado da Retina/fisiologia , Transcrição Genética/genética , Transcrição Genética/fisiologia
20.
Nat Commun ; 12(1): 3796, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34145278

RESUMO

The cell biology of circadian clocks is still in its infancy. Here, we describe an efficient strategy for generating knock-in reporter cell lines using CRISPR technology that is particularly useful for genes expressed transiently or at low levels, such as those coding for circadian clock proteins. We generated single and double knock-in cells with endogenously expressed PER2 and CRY1 fused to fluorescent proteins allowing us to simultaneously monitor the dynamics of CRY1 and PER2 proteins in live single cells. Both proteins are highly rhythmic in the nucleus of human cells with PER2 showing a much higher amplitude than CRY1. Surprisingly, CRY1 protein is nuclear at all circadian times indicating the absence of circadian gating of nuclear import. Furthermore, in the nucleus of individual cells CRY1 abundance rhythms are phase-delayed (~5 hours), and CRY1 levels are much higher (>5 times) compared to PER2 questioning the current model of the circadian oscillator.


Assuntos
Proteínas CLOCK/metabolismo , Relógios Circadianos/fisiologia , Criptocromos/metabolismo , Proteínas Circadianas Period/metabolismo , Análise de Célula Única/métodos , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Ritmo Circadiano/fisiologia , Criptocromos/genética , Técnicas de Introdução de Genes/métodos , Genes Reporter/genética , Células HCT116 , Humanos , Proteínas Circadianas Period/genética
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