Sleep deprivation alters pubertal timing in humans and rats: the role of the gut microbiome.

STUDY OBJECTIVES: Evidence implied that sleeping duration is associated with the timing of puberty and that sleep deprivation triggers early pubertal onset in adolescents. Sleep deprivation can affect metabolic changes and gut microbiota composition. This study investigated the effects of sleep deprivation on pubertal onset and gut microbiota composition in animal models and a human cohort. METHODS: This study comprised 459 boys and 959 girls from the Taiwan Pubertal Longitudinal Study. Sleep duration was evaluated using the self-report Pittsburgh Sleep Quality Index questionnaire. Early sexual maturation was defined by pediatric endocrinologist assessments. Mediation analyses were done to examine the association between sleep parameters, obesity, and early sexual maturation. Besides, Sprague Dawley juvenile rats were exposed to 4 weeks of chronic sleep deprivation. Vaginal opening (VO) and preputial separation (PS) were observed every morning to determine pubertal onset in female and male rats. RESULTS: The sleep-deprived juvenile rats in the sleep-deprived-female (SDF) and sleep-deprived-male (SDM) groups experienced delayed VO (mean VO days: 33 days in control; 35 days in SDF; p-value < 0.05) and PS (mean PS days: 42 days in control; 45 days in SDM; p-value < 0.05), respectively. Relative to their non-sleep-deprived counterparts, the sleep-deprived juvenile rats exhibited lower body weight and body fat percentage. Significant differences in relative bacterial abundance at genus levels and decreased fecal short-chain-fatty-acid levels were identified in both the SDF and SDM groups. In the human cohort, insufficient sleep increased the risk of early sexual maturation, particularly in girls (OR, 1.44; 95% CI: 1.09 to 1.89; p-value < 0.01). Insufficient sleep also indirectly affected early sexual maturation in girls, with obesity serving as the mediator. CONCLUSIONS: Overall, sleep deprivation altered the timing of puberty in both animal and human models but in different directions. In the rat model, sleep deprivation delayed the pubertal onset in juvenile rats through gut dysbiosis and metabolic changes, leading to a low body weight and body fat percentage. In the human model, sleep deprivation led to fat accumulation, causing obesity in girls, which increased the risk of early puberty.

Maternal Omega-3 Supplementation During Pregnancy, but Not Childhood Supplementation, Reduces the Risk of Food Allergy Diseases in Offspring.

BACKGROUND: Omega-3 supplementation has been reported to modulate immune responses and prevent food allergies among children; however, findings are inconsistent, and the timing of supplementation, which is critical, has not been thoroughly investigated. OBJECTIVE: To assess optimal timing (maternal vs childhood intake) of omega-3 supplementation for reducing food allergy risk among children in 2 periods (the first 3 years and beyond 3 years of age). METHODS: We performed a meta-analysis to assess the effects of maternal or childhood omega-3 supplementation on preventing the development of infant food allergies and food sensitizations. The PubMed/MEDLINE, Embase, Scopus, and Web of Science databases were searched for related studies published until October 30, 2022. We conducted dose-response and subgroup analyses to investigate the effects of omega-3 supplementation. RESULTS: We found that maternal omega-3 supplementation during pregnancy and lactation was significantly associated with decreased risks of infant egg sensitization (relative risk [RR]: 0.58, 95% confidence interval [95% CI]: 0.47-0.73, P < .01) and peanut sensitization (RR: 0.62, 95% CI: 0.47-0.80, P < .01) among children. Similar results were found in subgroup analyses for food allergy, egg sensitization, and peanut sensitization during the first 3 years of age and peanut sensitization and cashew nut sensitization beyond 3 years of age. Dose-response analysis showed a linear relationship between maternal omega-3 supplementation and infant egg sensitization risk during early life. By contrast, intake of omega-3 polyunsaturated fatty acid during childhood did not appear to significantly protect against food allergies. CONCLUSIONS: Maternal omega-3 supplementation during pregnancy and lactation, rather than childhood intake, reduces the risk of infant food allergy and food sensitization.

Effects of Resveratrol on Muscle Inflammation, Energy Utilisation, and Exercise Performance in an Eccentric Contraction Exercise Mouse Model.

Eccentric contraction can easily cause muscle damage and an inflammatory response, which reduces the efficiency of muscle contraction. Resveratrol causes anti-inflammatory effects in muscles, accelerates muscle repair, and promotes exercise performance after contusion recovery. However, whether resveratrol provides the same benefits for sports injuries caused by eccentric contraction is unknown. Thus, we explored the effects of resveratrol on inflammation and energy metabolism. In this study, mice were divided into four groups: a control group, an exercise group (EX), an exercise with low-dose resveratrol group (EX + RES25), and an exercise with high-dose resveratrol group (EX + RES150). The results of an exhaustion test showed that the time before exhaustion of the EX + RES150 group was greater than that of the EX group. Tumour necrosis factor-α (Tnfα) mRNA expression was lower in the EX + RES150 group than in the EX group. The energy utilisation of the EX + RES150 group was greater than that of the EX + RES25 group in different muscles. High-dose resveratrol intervention decreased Tnfα mRNA expression and enhanced the mRNA expressions of sirtuin 1, glucose transporter 4, AMP-activated protein kinase α1, and AMP-activated protein kinase α2 in muscles. These results revealed that high-dose resveratrol supplementation can reduce inflammation and oxidation and improve energy utilisation during short-duration high-intensity exercise.

Diagnostic Accuracy of Female Pelvic Ultrasonography in Differentiating Precocious Puberty From Premature Thelarche: A Systematic Review and Meta-analysis.

Background: The gonadotropin-releasing hormone (GnRH) stimulation test is the benchmark for diagnosing precocious puberty (PP). However, it is invasive, time-consuming, costly, and may create an unpleasant experience for participants. Moreover, some overlaps may occur between PP and premature thelarche (PT) in the early stage of PP. Female pelvic ultrasonography may provide additional information to help differentiate PP from PT and subsequently initiate early treatment. In this study, we aimed to first directly compare pelvic ultrasonography parameters between PP and PT groups and secondly, investigate their diagnostic accuracy compared with the GnRH stimulation test. Methods: A systematic search of the PubMed/MEDLINE, EMBASE, Scopus, and Cochrane Library databases was performed up to March 31, 2021. All types of studies, except for case reports and review articles, were included. The GnRH stimulation test was used to confirm PP diagnosis. Those whose organic conditions might cause PP were excluded. The mean, standard deviation, sensitivity, and specificity of each parameter were documented. Forest plots were constructed to display the estimated standardized mean differences (SMDs) from each included study and the overall calculations. A bivariate model was used to calculate the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR). Results: A total of 13 studies were included for analysis. The SMDs (95% confidence interval - CI) in ovarian volume, fundal-cervical ratio, uterine length, uterine cross-sectional area, and uterine volume between PP and PT groups were 1.12 (0.78-1.45; p < 0.01), 0.90 (0.07-1.73; p = 0.03), 1.38 (0.99-1.78; p < 0.01), 1.06 (0.61-1.50; p < 0.01), and 1.21 (0.84-1.58; p <0.01), respectively. A uterine length of 3.20 cm yielded a pooled sensitivity of 81.8% (95% CI 78.3%-84.9%), specificity of 82.0% (95% CI 61.0%-93.0%), PLR of 4.56 (95% CI 2.15-9.69), NLR of 0.26 (95% CI 0.17-0.39), and DOR of 19.62 (95% CI 6.45-59.68). The area under the summary receiver operating characteristics curve was 0.82. Conclusion: Female pelvic ultrasonography may serve as a complementary tool to the GnRH stimulation test in differentiating PP from PT. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021232427, ID: CRD42021232427.