Loss of diurnal behavioral rhythms and impaired lipid metabolism in growing pigs with mistimed feeding.

The misalignment of eating time and the endogenous circadian rhythm impairs the body's ability to maintain homeostasis. Although it is well established that children and growing animals differ from adults in their energy metabolism and behavioral patterns, little is known about how mistimed feeding disturbs the diurnal rhythms of behavior and metabolism in children and growing diurnal animals. In this study, growing pigs (diurnal animal) were randomly assigned to the daytime-restricted feeding (DRF) and nighttime-restricted feeding (NRF) groups for 5 weeks. Compared with observations in the DRF group, NRF disrupted the diurnal rhythm of behavior and clock genes and lowered the serum ghrelin, dopamine, and serotonin levels during the daytime and nighttime. Microbiome analysis results suggested that NRF altered the diurnal rhythm and composition of the gut microbiota, and increased log-ratios of Catenibacterium:Butyrivibrio and Streptococcus:Butyrivibrio. Based on the serum proteome, the results further revealed that rhythmic and upregulated proteins in NRF were mainly involved in oxidative stress, lipid metabolism, immunity, and cancer biological pathways. Serum physiological indicators further confirmed that NRF decreased the concentration of melatonin and fibroblast growth factor 21 during the daytime and nighttime, increased the diurnal amplitude and concentrations of very-low-density lipoprotein cholesterol, triglyceride, and total cholesterol, and increased the apolipoprotein B/ApoA1 ratio, which is a marker of metabolic syndrome. Taken together, this study is the first to reveal that mistimed feeding disrupts the behavioral rhythms of growing pigs, reprograms gut microbiota composition, reduces the serum levels of hormones associated with fighting depression and anxiety, and increases the risk of lipid metabolic dysregulation.

Prolonged melatonin treatment promote testicular recovery by enhancing RAC1-mediated apoptotic cell clearance and cell junction-dependent spermatogensis after heat stress.

INTRODUCTION: A decline in semen quality caused by global warming and torrid working conditions is a major cause of human male infertility, and heat stress-induced decreases in male reproductive ability results in economic losses in livestock husbandry. Increasing evidence suggests that melatonin exerts protective effects on stress-induced DNA damage and apoptosis in germ cells. However, few studies have assessed the effects of melatonin on testicular recovery during post-heat stress and the underlying mechanisms. METHODS AND RESULTS: In vivo studies using 8-week-old male CD-1 mice revealed that melatonin pretreatment (50 mg/kg for 5 days) did not alleviate heat stress-induced germ cell loss and disrupted testicular histomorphology, however, long-term melatonin administration after heat stress accelerated germ cell apoptosis, spermatogenic cell regeneration, and testicular weight recovery. In vitro studies demonstrated that melatonin enhanced RAC1 activity, resulting in increased phagocytosis of apoptotic germ cells by Sertoli cells. In addition, melatonin restored gap junctions and tight junctions after heat stress, thereby promoting hollow seminiferous tubule filling. DISCUSSION: Long-term melatonin administration accelerated testicular recovery after heat stress by enhancing the phagocytotic activity of Sertoli cells and the regeneration of spermatogenic cells. This finding suggests that melatonin is a potential therapeutic for heat stress-induced male infertility.

Night-Restricted Feeding Improves Gut Health by Synchronizing Microbe-Driven Serotonin Rhythm and Eating Activity-Driven Body Temperature Oscillations in Growing Rabbits.

The circadian misalignment of the gut microbiota caused by unusual eating times in adult animals is related to disease development. However, whether the composition and diurnal rhythm of gut microbiota can be optimized by synchronizing the window period of eating with natural eating habits to reduce the risk of diarrhea remains unclear, especially in growing animals. In this study, 108 5-week-old weaned rabbits (nocturnal animals) were randomly subjected to daytime feeding (DF) and night-restricted feeding (NRF). At age 12 weeks, six rabbits were selected from each group, and caecum and cecal contents, as well as serum samples were collected at 4-h intervals during 24 h. Overall, NRF was found to reduce the risk of diarrhea in growing rabbits, improved the diurnal rhythm and abundance of beneficial microorganisms, along with the production of beneficial metabolites, whereas reduced the abundance of potential pathogens (Synergistes, Desulfovibrio, and Alistipes). Moreover, NRF improved diurnal rhythm of tryptophan hydroxylase isoform 1 and serotonin. Furthermore, NRF strengthened the diurnal amplitude of body core temperature, and promoted the diurnal expression of intestinal clock genes (BMAL1, CLOCK, REV-ERBα, and PER1), and genes related to the regulation of the intestinal barrier (CLAUDIN-1), and intestinal epithelial cell self-proliferation and renewal (BMI1). In vitro simulation experiments further revealed that synchronization of microbial-driven serotonin rhythm and eating activity-driven body temperature oscillations, which are important zeitgebers, could promote the diurnal expression of clock genes and CLAUDIN-1 in rabbit intestinal epithelial cells (RIEC), and enhance RIEC proliferation. This is the first study to reveal that NRF reprograms the diurnal rhythm of the gut microbiome, promotes the diurnal expression of clock genes and tight junction genes via synchronization of microbial-driven serotonin rhythm and eating activity-driven body temperature oscillations, thereby improving intestinal health and reducing the risk of diarrhea in growing rabbits. Collectively, these results provide a new perspective for the healthy feeding and management of growing animals.

Night-restricted feeding improves locomotor activity rhythm and modulates nutrient utilization to accelerate growth in rabbits.

An unfavorable lifestyle disrupts the circadian rhythm, leading to metabolic dysfunction in adult humans and animals. Increasing evidence suggests that night-restricted feeding (NRF) can effectively prevent ectopic fat deposition caused by circadian rhythm disruption, and reduce the risk of metabolic diseases. However, previous studies have mainly focused on the prevention of obesity in adults by regulating dietary patterns, whereas limited attention has been paid to the effect of NRF on metabolism during growth and development. Here, we used weaning rabbits as models and found that NRF increased body weight gain without increasing feed intake, and promoted insulin-mediated protein synthesis through the mTOR/S6K pathway and muscle formation by upregulating MYOG. NRF improved the circadian clock, promoted PDH-regulated glycolysis and CPT1B-regulated fatty-acid ß-oxidation, and reduced fat content in the serum and muscles. In addition, NRF-induced body temperature oscillation might be partly responsible for the improvement in the circadian clock and insulin sensitivity. Time-restricted feeding could be used as a nondrug intervention to prevent obesity and accelerate growth in adolescents.

The hornwort genome and early land plant evolution.

Hornworts, liverworts and mosses are three early diverging clades of land plants, and together comprise the bryophytes. Here, we report the draft genome sequence of the hornwort Anthoceros angustus. Phylogenomic inferences confirm the monophyly of bryophytes, with hornworts sister to liverworts and mosses. The simple morphology of hornworts correlates with low genetic redundancy in plant body plan, while the basic transcriptional regulation toolkit for plant development has already been established in this early land plant lineage. Although the Anthoceros genome is small and characterized by minimal redundancy, expansions are observed in gene families related to RNA editing, UV protection and desiccation tolerance. The genome of A. angustus bears the signatures of horizontally transferred genes from bacteria and fungi, in particular of genes operating in stress-response and metabolic pathways. Our study provides insight into the unique features of hornworts and their molecular adaptations to live on land.

[Comparative study of primordial germ cells in male and female mouse embryos].

OBJECTIVE: To investigate the differences in the development of primordial germ cells (PGCs) between male and female mouse embryos. METHODS: The morphological changes of genital ridge development were detected in C57BL/6J mouse embryos of 11-13.5 days, and the changes of PGCs quantity and proliferation were compared between the male and female embryos using immunofluorescence histochemistry. RESULTS: The PGCs was the most numerous at 13.5 days in male and female embryos, and the quantity of proliferating PGCs reached the maximum at 13 days. The quantity of PGCs and proliferating PGCs in male embryos at 13 days was significantly larger than that in female embryos. CONCLUSION: The development of PGCs is characterized by a gender differences in early development of mouse embryos (11-13.5 days).