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Circadian rhythms are intrinsic biological processes that regulate a wide range of physiological functions, aligning them with the 24-hour day-night cycle. Animal models play a pivotal role in elucidating the molecular mechanisms underlying circadian rhythms and their disruption, providing valuable insights into translational approaches for managing circadian-related disorders. This review explores the strengths and limitations of various animal models, including rodents, zebrafish, and non-human primates, highlighting their contributions to understanding circadian regulation and their translational relevance to human health. We discuss innovative methodologies, such as multi-omics, systems biology, and gene editing that enhance the utility of these models, as well as the emerging role of humanized animal models and organoids in bridging the gap between preclinical research and clinical application. Additionally, we examine the potential of circadian animal models to inform chronotherapeutic strategies, offering new perspectives on optimizing treatment timing to improve patient outcomes. [ABSTRACT FROM AUTHOR]

Chronotype refers to individual differences in the circadian phase that affect a person's biological and psychological functioning. One of the most useful tools for measuring chronotype in children aged 4 – 11 years is the Children's Chronotype Questionnaire (CCTQ). Therefore, due to the importance of measuring chronotype in children and also the lack of a standard scale in Iran, this study aimed to examine the reliability and validity of the Persian version of this questionnaire for children. The participants of this cross-sectional study were 272 Iranian children aged five to eleven years with their parents, selected by convenience sampling method. To collect data, all participants completed the CCTQ and the Children's Sleep Habits Questionnaire (CSHQ), which were examined by the researchers for their construct and concurrent validity. Over a period of three weeks, 50 mothers participated in a test of the test-retest reliability of the CCTQ. During this time, their sleep patterns were monitored using a sleep diary to test for reliability. The Cronbach's alpha of the CCTQ-M/E was 0.71. Test-retest reliability using the Spearman correlation coefficient between two observations with an interval of three weeks was 0.83. The MSFsc index was significantly correlated with M/E, CT, and most of the parent-reported sleep/wake parameters. In addition, the three indicators of the CCTQ were significantly associated with most of the sleep/wake parameters of the sleep diary and the components of the CSHQ. The Persian version of the CCTQ has desirable psychometric properties for the assessment of chronotype in five- to eleven-year-old children. [ABSTRACT FROM AUTHOR]

Modern societies grapple with an escalating prevalence of sleep problems and addiction. This nexus warrants exploration, particularly concerning preventive strategies. Hence, this study endeavors to elucidate the interplay between sleep problems, social jet lag, chronotype, and addiction susceptibility. The present research, applying a cross-sectional correlational design, employed 180 Iranian adults through internet invitations. Research data were collected using the Iranian Addiction Potential Scale (IAPS), MCTQ, ESS, and rMEQ. The findings highlight the predictive role of ESS, weekly sleep duration, social jet lag, and rMEQ in addiction potential. It is worth mentioning that there was no significant association between MSFsc and morning/evening chronotype and addiction potential. The results indicate the importance of identifying and supporting individuals predisposed to addiction. According to the results, it seems that sleep problems, sleep duration, and social jet lag are more important variables in preventing addiction, so sleep hygiene programs are suggested. [ABSTRACT FROM AUTHOR]

Purpose: Currently, the most useful questionnaire for determining the chronotype is the Munich ChronoType Questionnaire (MCTQ). It determines chronotype based on sleep–wake behavior on workdays and work-free days and uses the mid-sleep time on free days (MSF), corrected for accumulated sleep debt over the work week to classify chronotype (MSFsc). Our study aimed at validating Persian version of the MCTQ. Methods: Participants completed the Persian version of the MCTQ, reduced Morningness-Eveningness Questionnaire (rMEQ), Epworth sleepiness scale (ESS), and demographic characteristics. Results: The study sample was comprised of 250 Iranian men and women (mean age 34 years, age range 30 to 58 years, 113 men). Results showed that there is a significant negative relationship between the components of MCTQ and rMEQ, and the strongest relationship related to the MSF index. The results also showed that MCTQ parameters were not significantly related to the ESS scale. Cut-off values of MSFsc for chronotype categories were determined by inter-quartile range (Q25% = 3.44, Q50% = 4.68, and Q75% = 5.75). Conclusions: Like the MCTQ in other languages, the Persian version of the MCTQ is a reliable tool for assessing chronotype. [ABSTRACT FROM AUTHOR]

Background: The Yale Food Addiction Scale version 2.0 (YFAS 2.0) is used for the assessment of food addiction (FA). This research intended to evaluate the validity of the Persian translation of the questionnaire and to investigate the psychological properties and the association between FA and anthropometric indices. Methods: In a sample of 473 nonclinical participants, FA, binge eating, and objectively measured anthropometric indices were assessed. Internal consistency, convergent, and validity of the PYFAS 2.0 were examined. Also, the factor structure (confirmatory factor analysis following the 11 diagnostic indicators in addition to the significant distress) and the construct of the scale were evaluated. Findings: The frequencies of mild, moderate, and severe FA based on PYFAS 2.0 were 0.2%, 10%, and 5.5%, respectively. The findings supported a one-factor structure. The confirmatory factor analysis revealed a good construct validity (RMSEA = 0.043, χ2 = 76.38, df = 41, χ2 (CMIN)/df = 1.862, GFI = 0.975, AGFI = 0.957, IFI = 0.986, RFI = 0.958, ECVI = 0.319, TLI = 0.978). For both the diagnostic and symptom count versions, the PYFAS 2.0 presented acceptable internal consistency (IC) (Kuder-Richardson 20 = 0.99 and McDonald omega = 0.91). Conclusion: The PYFAS 2.0 was a psychometrically sound instrument in an Iranian non-clinical population. This questionnaire can be used to study FA in Persian non-clinical populations. Future research should study the psychometric characteristics of this scale in high-risk groups. [ABSTRACT FROM AUTHOR]

Investigations have demonstrated that circadian rhythm can affect animal curiosity, also a significant correlation has been reported between curiosity and addiction. So the aim of this study is to evaluate the effect of circadian fluctuation in curiosity on addiction. For this purpose, we used the open field (OF) test and conditioned place preference (CPP) biased paradigm. In the OF we evaluated animals curiosity in the morning (ZT 1-2) and in the evening (ZT 11-12). In the CPP, during six training sessions held either in the morning or evening, morphine was injected in a specific compartment. Rats were subsequently tested for preferring the drug-paired chamber at the circadian time that either matched or was different from that of training. The evening rats, compared with the morning groups more spent their time in the center of the OF and also showed a higher preference for staying in the white box in CPP apparatus, and if received morphine at this time, they were conditioned more than morning. The finding of this study showed that the curiosity in rats is higher in the evening and zeitgeber time is more potent for conditioned to morphine than in the morning. [ABSTRACT FROM AUTHOR]

Chronotype refers to individual differences in the circadian phase that affect a person's biological and psychological functioning. One of the most useful tools for measuring chronotype in children aged 4 – 11 years is the Children's Chronotype Questionnaire (CCTQ). Therefore, due to the importance of measuring chronotype in children and also the lack of a standard scale in Iran, this study aimed to examine the reliability and validity of the Persian version of this questionnaire for children. The participants of this cross-sectional study were 272 Iranian children aged five to eleven years with their parents, selected by convenience sampling method. To collect data, all participants completed the CCTQ and the Children's Sleep Habits Questionnaire (CSHQ), which were examined by the researchers for their construct and concurrent validity. Over a period of three weeks, 50 mothers participated in a test of the test-retest reliability of the CCTQ. During this time, their sleep patterns were monitored using a sleep diary to test for reliability. The Cronbach's alpha of the CCTQ-M/E was 0.71. Test-retest reliability using the Spearman correlation coefficient between two observations with an interval of three weeks was 0.83. The MSFsc index was significantly correlated with M/E, CT, and most of the parent-reported sleep/wake parameters. In addition, the three indicators of the CCTQ were significantly associated with most of the sleep/wake parameters of the sleep diary and the components of the CSHQ. The Persian version of the CCTQ has desirable psychometric properties for the assessment of chronotype in five- to eleven-year-old children. [ABSTRACT FROM AUTHOR]

Objective: Prenatal alcohol exposure causes fetal developmental abnormalities via mitochondrial dysfunction, reactive oxygen species (ROS) formation, and oxidative stress. Therefore, we aimed to investigate the potential of hesperidin as a mitochondrial protective and antioxidative agent in newborn male rats as a model for fetal alcohol syndrome (FAS). Method: Newborn male rats were divided randomly into five groups: a sham group (receiving 27.8 ml/kg milk solution, orally), an ethanol group (5.25 g/kg in milk solution, orally, 2-10 days after birth), an ethanol + hesperidin group (25 mg/kg/day orally), an ethanol + hesperidin group (50 mg/kg/day orally), and an ethanol + hesperidin group (100 mg/kg/day orally). Thirty-six days after birth, newborn male rats were sacrificed and brain mitochondria were isolated using differential centrifugation. Mitochondrial toxicity biomarkers of succinate dehydrogenase (SDH) activity, mitochondrial swelling, mitochondrial membrane potential (MMP), and ROS were measured. Results: Offspring neonatally exposed to ethanol showed a significant reduction in SDH activity, mitochondrial swelling, MMP collapse, induction of ROS formation, and lipid peroxidation in isolated mitochondria. Oral administration of hesperidin restored SDH activity, improved MMP collapse and mitochondrial swelling, and reduced ROS formation. Conclusions: This study demonstrates that hesperidin exerts a potent protective effect against alcohol-induced mitochondrial toxicity in the FAS model. Moreover, these findings indicate that hesperidin might be a useful compound for prevention of alcohol-induced fetal developmental abnormalities during pregnancy. [ABSTRACT FROM AUTHOR]

Objective: Ellagic acid (EA) exerts neuroprotective, mitoprotective, anti-oxidative, and anti-inflammatory effects. We evaluated the protective effect of EA on ethanol-induced fetal alcohol spectrum disorders (FASD)., Method: A total of 35 newborn male rats were used, divided into five groups, including control (normal saline), ethanol (5.25 g/kg per day), ethanol (5.25 g/kg per day) + EA (10 mg/kg), ethanol (5.25 g/kg per day) + EA (20 mg/kg), and ethanol (5.25 g/kg per day) + EA (40 mg/kg). Thirty-six days after birth, behavioral tests (Morris water maze and Elevated Plus Maze), tumor necrosis factor-alpha (TNF-alpha) levels, oxidative markers (malondialdehyde, glutathione, and superoxide dismutase), and mitochondrial examination such as succinate dehydrogenases activity, mitochondrial swelling, mitochondrial membrane potential, and reactive oxygen species formation were analyzed., Results: The results revealed that ethanol exposure adversely affected cognitive and mitochondrial functions and induced oxidative stress and inflammation in brain tissue. However, EA (20 and 40 mg/kg) administration effectively prevented the toxic effects of ethanol in the FASD model., Conclusions: These findings demonstrate that ethanol application significantly impairs brain development via mitochondrial dysfunction and induction of oxidative stress. These data indicate that EA might be a useful compound for the prevention of alcohol-induced FASD.