Chronic Jet Lag Exacerbates Jejunal and Colonic Microenvironment in Mice

Colonic Submucosa Targeted Delivery of Probiotic and Rhein for Ulcerative Colitis Treatment

Ulcerative colitis (UC) is a chronic disease. A significant challenge for the management of UC is to achieve delivery of drugs to the multi-layer colonic barriers, as existing drugs are difficult to penetrate these depths. In this study, a novel drug delivery system using yeast cell wall microparticles (YPs) are developed to co-encapsulate Bacillus subtilis (BS) and Rhein (Rh) termed Rh-YBS. This system specifically targets colonic microfold cells, enabling direct delivery of BS to the colonic submucosa. Additionally, Rh enhances BS colonization in the submucosa through floral regulation. Studies indicate that Rh-YBS can effectively reach and proliferate within the submucosa in vivo. In a DSS-induced UC mouse model, Rh-YBS stimulates the CGRP-related neural pathway; BS activation in the submucosa leads to increased CGRP secretion, prompting goblet cells to secrete mucus and thereby repairing the mucosa. Furthermore, the Rh-YBS also provide a preventive benefit against UC. In summary, Rh-YBS represents an innovative drug delivery system for mucosal repair in UC treatment, activating a unique mechanism involving the CGRP-related neural pathway.

In Vitro Biotransformation of Ziziphi Spinosae Semen Saponins by Gut Microbiota from Healthy and Insomniac Groups

Ziziphi Spinosae Semen saponins (ZSSS) show sedative-hypnotic activity but have very low bioavailability, potentially due to their conversion into bioactive metabolites by gut microbiota. In this study, the biotransformation of ZSSS by gut microbiota from healthy humans and patients with insomnia in vitro was analyzed. A total of 21 prototype compounds and 49 metabolites were identified using UHPLC-Q-Orbitrap-MS. Deglycosylation, deoxygenation, dehydration, and deacylation were detected in both healthy individuals and insomniacs. However, oxidation and hydrogenation were uniquely observed in insomniacs. ZSSS can enhance beneficial bacteria, such as Veillonella, Dialister, and Bacteroides. ZSSS can promote the synthesis of short-chain fatty acids (SCFAs), especially acetic acid, propionic acid, and butyric acid. Furthermore, it was found that the sedative-hypnotic activity of ZSSS was enhanced after biotransformation, as determined by a sodium pentobarbital-induced sleeping test (SPST), open-field behavior test (OFBT), and molecular docking experiment (MDE). These results collectively offer valuable insight into the mechanism of action of ZSSS.

Frequent Shifts During Chronic Jet Lag Uncouple Liver Rhythms From the Light Cycle in Male Mice

Circadian disruption is pervasive in modern society and associated with increased risk of disease. Chronic jet lag paradigms are popular experimental tools aiming to emulate human circadian disruption experienced during rotating and night shift work. Chronic jet lag induces metabolic phenotypes tied to liver and systemic functions, yet lack of a clear definition for how rhythmic physiology is impaired under these conditions hinders the ability to identify the underlying molecular mechanisms. Here, we compared 2 common chronic jet lag paradigms and found that neither induced arrythmicity of the liver and each had distinct effects on rhythmicity. Instead, more frequent 8-h forward shifts of the light schedule induced more severe misalignment and non-fasted hyperglycemia. Every other day shifts eventually uncoupled behavioral and hepatic rhythms from the light cycle, reminiscent of free-running conditions. These results point to misalignment, not arrhythmicity, as the initial disturbance tied to metabolic dysfunction in environmental circadian disruption and highlight considerations for the interpretation and design of chronic jet lag studies.

Correlation analysis of the impact of Clonorchis sinensis juvenile on gut microbiota and transcriptome in mice

Clonorchiasis remains a non-negligible global zoonosis, imposing serious socio-economic burdens in endemic regions. The interplay between gut microbiota and the host transcriptome is crucial for maintaining health; however, the impact of Clonorchiasis sinensis juvenile infection on these factors is still poorly understood. This study aimed to investigate their relationship and potential pathogenic mechanisms. The BALB/c mouse model of early infection with C. sinensis juvenile was constructed. Pathological analyses revealed that C. sinensis juvenile triggered liver inflammation, promoted intestinal villi growth, and augmented goblet cell numbers in the ileum. Additionally, the infection altered the diversity and structure of gut microbiota, particularly affecting beneficial bacteria that produce short-chain fatty acids, such as Lactobacillus and Muribaculaceae, and disrupted the Firmicutes/Bacteroidetes ratio. Gut transcriptome analysis demonstrated an increase in the number of differentially expressed genes (DEGs) as infection progressed. Enriched Gene Ontology items highlighted immune and detoxification-related processes, including immunoglobulin production and xenobiotic metabolic processes. Kyoto Encyclopedia of Genes and Genomes pathway analysis further indicated involvement in circadian rhythm, as well as various detoxification and metabolic-related pathways (e.g., glutathione metabolism and glycolysis/gluconeogenesis). Prominent DEGs associated with these pathways included Igkv12-41, Mcpt2, Arntl, Npas2, Cry1, and Gsta1. Correlation analysis additionally identified Bacteroides_sartorii as a potential key regulator in the interaction between gut microbiota and transcriptome. This study sheds light on the alterations in gut microbiota and transcriptome in mice following C. sinensis juvenile infection, as well as their correlation, laying a foundation for a better understanding of their interaction during infection.

IMPORTANCE

This study highlighted the impact of C. sinensis juvenile infection on the gut microbiota and transcriptome of BALB/c mice. It induced liver inflammation, promoted intestinal villi growth, and altered goblet cell numbers. The infection also disrupted the diversity and structure of gut microbiota, particularly affecting beneficial bacteria. Transcriptome analysis revealed increased expression of genes related to immune response and detoxification processes. Important pathways affected included circadian rhythm, glutathione metabolism, and glycolysis/gluconeogenesis. Notable genes implicated included Igkv12-41, Mcpt2, Arntl, Npas2, Cry1, and Gsta1. Bacteroides_sartorii emerged as a potential key regulator in this interaction.

The circadian clock gene period regulates the composition and daily bacterial load of the gut microbiome in Drosophila melanogaster

While Drosophila melanogaster serves as a crucial model for investigating both the circadian clock and gut microbiome, our understanding of their relationship in this organism is still limited. Recent analyses suggested that the Drosophila gut microbiome modulates the host circadian transcriptome to minimize rapid oscillations in response to changing environments. Here, we examined the composition and abundance of the gut microbiota in wild-type and arrhythmic per01 flies, under 12 h:12 h light: dark (12:12 LD) and constant darkness (DD) conditions. The gut microbiota of wild-type and per01 flies showed differences in composition, suggesting that the D. melanogaster circadian gene per has a role in shaping the gut microbiome. In 12:12 LD and DD conditions, per01 mutants showed significant daily variations in gut bacterial quantity, unlike wild-type flies. This suggests that per is involved in maintaining the daily stability of gut microbiome load in D. melanogaster. Expanding these analyses to other fly strains with disrupted circadian clocks will clarify whether these effects originate from a circadian function of per or from its possible pleiotropic effects. Finally, some gut bacteria exhibited significant 24 h fluctuations in their relative abundance, which appeared independent from the fly circadian clock, suggesting that certain gut commensal bacteria in Drosophila may possess a host-independent circadian clock.

Melatonin Alleviates Circadian Rhythm Disruption-Induced Enhanced Luteinizing Hormone Pulse Frequency and Ovarian Dysfunction

Circadian rhythm disruption (CRD), stemming from sleep disorders and/or shift work, is a risk factor for reproductive dysfunction. CRD has been reported to disturb nocturnal melatonin signaling, which plays a crucial role in female reproduction as a circadian regulator and an antioxidant. The hypothalamic-pituitary-ovarian (HPO) axis regulates female reproduction, with luteinizing hormone (LH) pulse pattern playing a pivotal role in folliculogenesis and steroidogenesis. However, the effect of CRD on the HPO axis and the involvement of melatonin remains unclear. Female CBA/CaJ mice underwent CRD modeling, which involves alternating between standard light conditions and an 8-h advance schedule every 3 days for 8 weeks, whereas control mice were maintained under a standard 12:12-h light/dark (LD) cycle. Subsequent measurements of diurnal melatonin levels, LH pulse patterns assessments via serial tail-tip blood sampling and evaluations of ovarian function were conducted. CRD altered the circadian rhythms of wheel-running activity and melatonin secretion in mice and led to an augmented LH pulse pattern, evidenced by increased LH pulse frequency, mean LH levels, and pituitary LH beta-subunit (LHβ) expression, irregular estrous cycles, abnormal luteal function, altered endocrine function, and ovarian oxidative stress. Melatonin treatment (10 mg/kg/day for 4 weeks) significantly improved the HPO axis disorder in CRD mice, decreasing the enhanced LH pulse frequency and pituitary LHβ expression. These findings were further validated using an in vitro LβT2 cell perfusion model. Furthermore, melatonin restored ovarian function and scavenged reactive oxygen species, thereby preventing apoptosis and preserving ovarian function. This study offers new insights into the impact of CRD on the HPO axis and emphasizes the potential of melatonin supplementation in mitigating its effects on female reproduction.

Exploring gut microbiota diurnal fluctuation in alcohol-dependent patients with sleep disturbance

Introduction. Alcohol dependence (AD) and sleep disturbance (SD) independently affect gut microbiota, potentially disrupting the circadian rhythm of the microbiota and the host. However, the impact of SD on the composition and rhythmicity of gut flora in AD patients remains poorly understood.Gap Statement. Characteristics of gut flora and diurnal oscillations in AD patients experiencing SD are unknown.Aim. This study aims to explore alterations in gut flora and diurnal oscillations in AD patients experiencing SD.Methodology. Thirty-two AD patients and 20 healthy subjects participated, providing faecal samples at 7 : 00 AM, 11 : 00 AM, 3 : 00 PM and 7 : 00 PM for gut microbiota analysis using 16S rDNA sequencing. AD patients were further categorized into those with poor sleep (ADwPS) and those with good sleep (ADwGS) for further analyses.Results. The ADwPS group demonstrated elevated levels of anxiety, depression and withdrawal severity compared to the ADwGS group (all P<0.05). The β-diversity of gut microbiota in the ADwPS group differed from that in the ADwGS group (P<0.05). Bacterial abundances at various taxonomic levels, including Cyanobacteria and Pseudomonadales, differed between the ADwPS and ADwGS groups (all P<0.05). Utilizing unweighted UniFrac analysis, the β-diversity of gut microbiota in the ADwPS group demonstrated robust diurnal oscillation (P<0.05), whereas this pattern was statistically insignificant in the ADwGS group. Notably, the abundance of pathogenic bacteria like Pseudomonadales and Pseudomonadaceae exhibited marked diurnal fluctuation in the ADwPS group (all P<0.05).Conclusion. SD in AD patients extends beyond alcohol-induced alterations, impacting gut microbiota composition, function and diurnal oscillation patterns. This highlights its add-on influence, supplementing AD-related changes.

Gut microbiota and sleep: Interaction mechanisms and therapeutic prospects

Sleep is crucial for wellness, and emerging research reveals a profound connection to gut microbiota. This review explores the bidirectional relationship between gut microbiota and sleep, exploring the mechanisms involved and the therapeutic opportunities it presents. The gut-brain axis serves as a conduit for the crosstalk between gut microbiota and the central nervous system, with dysbiosis in the microbiota impairing sleep quality and vice versa. Diet, circadian rhythms, and immune modulation all play a part. Specific gut bacteria, like Lactobacillus and Bifidobacterium, enhance sleep through serotonin and gamma-aminobutyric acid production, exemplifying direct microbiome influence. Conversely, sleep deprivation reduces beneficial bacteria, exacerbating dysbiosis. Probiotics, prebiotics, postbiotics, and fecal transplants show therapeutic potential, backed by animal and human research, yet require further study on safety and long-term effects. Unraveling this intricate link paves the way for tailored sleep therapies, utilizing microbiome manipulation to improve sleep and health. Accelerated research is essential to fully tap into this promising field for sleep disorder management.

Sleep and circadian rhythm disturbance in kidney stone disease: a narrative review

The circadian rhythm generated by circadian clock genes functions as an internal timing system. Since the circadian rhythm controls abundant physiological processes, the circadian rhythm evolved in organisms is salient for adaptation to environmental change. A disturbed circadian rhythm is a trigger for numerous pathological events. Recently, accumulated data have indicated that kidney stone disease (KSD) is related to circadian rhythm disturbance. However, the mechanism between them has not been fully elucidated. In this narrative review, we summarized existing evidence to illustrate the possible association between circadian rhythm disturbance and KSD based on the epidemiological studies and risk factors that are linked to circadian rhythm disturbance and discuss some chronotherapies for KSD. In summary, KSD is associated with systemic disorders. Metabolic syndrome, inflammatory bowel disease, and microbiome dysbiosis are the major risk factors supported by sufficient data to cause KSD in patients with circadian rhythm disturbance, while others including hypertension, vitamin D deficiency, parathyroid gland dysfunction, and renal tubular damage/dysfunction need further investigation. Then, some chronotherapies for KSD were confirmed to be effective, but the molecular mechanism is still unclear.

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.

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.