Abnormal Eating Patterns Cause Circadian Disruption and Promote Alcohol-Associated Colon Carcinogenesis

Chronobiology of the Tumor Microenvironment: Implications for Therapeutic Strategies and Circadian-Based Interventions

Numerous research works have emphasized the critical role that circadian rhythm plays in the tumor microenvironment (TME). The goal of clarifying chrono-pharmacological strategies for improving cancer treatment in clinical settings is a continuous endeavor. Consequently, to enhance the use of time-based pharmaceutical therapies in oncology, combining existing knowledge on circadian rhythms' roles within the TME is essential. This perspective elucidates the functions of circadian rhythms in the TME across various stages of cancer development, progression, and metastasis. Specifically, aging, angiogenesis, and inflammation are implicated in modulating circadian rhythm within the TME. Furthermore, circadian rhythm exerts a profound influence on current cancer treatments and thereby generates chronotheray to manage tumors. From a TME perspective, circadian rhythm offers promising opportunities for cancer prevention and treatment; nevertheless, further study is needed to address unanswered scientific problems.

Distinct intestinal microbial signatures linked to accelerated systemic and intestinal biological aging

BACKGROUND

People living with HIV (PLWH), even when viral replication is controlled through antiretroviral therapy (ART), experience persistent inflammation. This inflammation is partly attributed to intestinal microbial dysbiosis and translocation, which may lead to non-AIDS-related aging-associated comorbidities. The extent to which living with HIV - influenced by the infection itself, ART usage, sexual orientation, or other associated factors - affects the biological age of the intestines is unclear. Furthermore, the role of microbial dysbiosis and translocation in the biological aging of PLWH remains to be elucidated. To investigate these uncertainties, we used a systems biology approach, analyzing colon and ileal biopsies, blood samples, and stool specimens from PLWH on ART and people living without HIV (PLWoH) as controls.

RESULTS

PLWH exhibit accelerated biological aging in the colon, ileum, and blood, as measured by various epigenetic aging clocks, compared to PLWoH. Investigating the relationship between microbial translocation and biological aging, PLWH had decreased levels of tight junction proteins in the intestines, along with increased microbial translocation. This intestinal permeability correlated with faster biological aging and increased inflammation. When investigating the relationship between microbial dysbiosis and biological aging, the intestines of PLWH had higher abundance of specific pro-inflammatory bacteria, such as Catenibacterium and Prevotella. These bacteria correlated with accelerated biological aging. Conversely, the intestines of PLWH had lower abundance of bacteria known for producing the anti-inflammatory short-chain fatty acids, such as Subdoligranulum and Erysipelotrichaceae, and these bacteria were associated with slower biological aging. Correlation networks revealed significant links between specific microbial genera in the colon and ileum (but not in feces), increased aging, a rise in pro-inflammatory microbe-related metabolites (e.g., those in the tryptophan metabolism pathway), and a decrease in anti-inflammatory metabolites like hippuric acid.

CONCLUSIONS

We identified specific microbial compositions and microbiota-related metabolic pathways that are intertwined with intestinal and systemic biological aging. This microbial signature of biological aging is likely reflecting various factors including the HIV infection itself, ART usage, sexual orientation, and other aspects associated with living with HIV. A deeper understanding of the mechanisms underlying these connections could offer potential strategies to mitigate accelerated aging and its associated health complications. Video Abstract.

Distinct Intestinal Microbial Signatures Linked to Accelerated Biological Aging in People with HIV

Background

People with HIV (PWH), even with controlled viral replication through antiretroviral therapy (ART), experience persistent inflammation. This is partly due to intestinal microbial dysbiosis and translocation. Such ongoing inflammation may lead to the development of non-AIDS-related aging-associated comorbidities. However, there remains uncertainty regarding whether HIV affects the biological age of the intestines and whether microbial dysbiosis and translocation influence the biological aging process in PWH on ART. To fill this knowledge gap, we utilized a systems biology approach, analyzing colon and ileal biopsies, blood samples, and stool specimens from PWH on ART and their matched HIV-negative counterparts.

Results

Despite having similar chronological ages, PWH on ART exhibit accelerated biological aging in the colon, ileum, and blood, as measured by various epigenetic aging clocks, compared to HIV-negative controls. Investigating the relationship between microbial translocation and biological aging, PWH on ART had decreased levels of tight junction proteins in the colon and ileum, along with increased microbial translocation. This increased intestinal permeability correlated with faster intestinal and systemic biological aging, as well as increased systemic inflammation. When investigating the relationship between microbial dysbiosis and biological aging, the intestines of PWH on ART had higher abundance of specific pro-inflammatory bacterial genera, such as Catenibacterium and Prevotella. These bacteria significantly correlated with accelerated local and systemic biological aging. Conversely, the intestines of PWH on ART had lower abundance of bacterial genera known for producing short-chain fatty acids and exhibiting anti-inflammatory properties, such as Subdoligranulum and Erysipelotrichaceae, and these bacteria taxa were associated with slower biological aging. Correlation networks revealed significant links between specific microbial genera in the colon and ileum (but not in feces), increased aging, a rise in pro-inflammatory microbial-related metabolites (e.g., those in the tryptophan metabolism pathway), and a decrease in anti-inflammatory metabolites like hippuric acid and oleic acid.

Conclusions

We identified a specific microbial composition and microbiome-related metabolic pathways that are intertwined with both intestinal and systemic biological aging in PWH on ART. A deeper understanding of the mechanisms underlying these connections could potentially offer strategies to counteract premature aging and its associated health complications in PWH.

Regulatory effects of ketogenic diet on the inflammatory response in obese Saudi women

Objective

In recent years, the use of a ketogenic diet (KD) against obesity has gained popularity in KSA. This study was designed to determine the impact of KD on anthropometric indices and on the abnormal regulation of inflammatory activities in obese Saudi women. Moreover, we investigated the potential of beta-hydroxybutyrate (BHB) supplementation on the inhibition of pro-inflammatory activities.

Methods

We enrolled 31 Saudi women (aged, 35.3 ± 8.4 years) with an average BMI of 33.96 ± 4.44 kg/m² underwent an 8-week KD (8KD) from January to March 2021. Changes in anthropometric measurements were collected at baseline and after 4-8 weeks of intervention. Compliance with the dietary regimen was monitored weekly by plasma BHB level.

Results

Twenty-nine females commenced the diets and 23 completed the study (a 79% completion rate). In comparison to pre-intervention, the 8KD resulted in a significant increase in the levels of plasma BHB (P < 0.001) throughout the duration of the trial. This was accompanied by a significant reduction in weight loss (7.7 kg ± 11.3; P < 0.001), BMI, waist circumference (P < 0.001), and levels of the inflammatory cytokine IL-1β (P < 0.001).

Conclusions

An 8-week KD was found to be useful in producing a positive impact on anthropometric indices, biochemical and inflammatory processes. This study indicated that the intake of a KD by obese Saudi women induced the release of BHB in the blood without stimulation of an overall starvation response. This may be useful to alleviate the severity of chronic inflammatory disorders associated with obesity.

Overview of the Gut-Brain Axis: From Gut to Brain and Back Again

The gut-brain axis refers to a bidirectional communication pathway linking the gastrointestinal system to the central nervous system. The hardware of this multifaceted pathway takes many forms, at once structural (neurons, microglia, intestinal epithelial cell barrier), chemical (neurotransmitters, enteroendocrine hormones, bacterial metabolites), and cellular (immune signaling, inflammatory pathways). The gut-brain axis is exquisitely influenced by our environment, diet, and behaviors. Here, we will describe recent progress in understanding the gut-brain axis in neurological disease, using Parkinson's disease as a guide. We will see that each component of the gut-brain axis is heavily mediated by intestinal microbiota and learn how gut-brain communication can go awry in microbial dysbiosis.

"Time" for obesity-related cancer: The role of the circadian rhythm in cancer pathogenesis and treatment

The circadian rhythm is regulated by an intrinsic time-tracking system, composed both of a central and a peripheral clock, which influences the cycles of activities and sleep of an individual over 24 h. At the molecular level, the circadian rhythm begins when two basic helix-loop-helix/Per-ARNT-SIM (bHLH-PAS) proteins, BMAL-1 and CLOCK, interact with each other to produce BMAL-1/CLOCK heterodimers in the cytoplasm. The BMAL-1/CLOCK target genes encode for the repressor components of the clock, cryptochrome (Cry1 and Cry2) and the Period proteins (Per1, Per2 and Per3). It has been recently demonstrated that the disruption of circadian rhythm is associated with an increased risk of developing obesity and obesity-related diseases. In addition, it has been demonstrated that the disruption of the circadian rhythm plays a key role in tumorigenesis. Further, an association between the circadian rhythm disruptions and an increased incidence and progression of several types of cancer (e.g., breast, prostate, colorectal and thyroid cancer) has been found. As the perturbation of circadian rhythm has adverse metabolic consequences (e.g., obesity) and at the same time tumor promoter functions, this manuscript has the aim to report how the aberrant circadian rhythms affect the development and prognosis of different types of obesity-related cancers (breast, prostate, colon rectal and thyroid cancer) focusing on both human studies and on molecular aspects.

Circadian disruption: from mouse models to molecular mechanisms and cancer therapeutic targets

The circadian clock is a timekeeping system for numerous biological rhythms that contribute to the regulation of numerous homeostatic processes in humans. Disruption of circadian rhythms influences physiology and behavior and is associated with adverse health outcomes, especially cancer. However, the underlying molecular mechanisms of circadian disruption-associated cancer initiation and development remain unclear. It is essential to construct good circadian disruption models to uncover and validate the detailed molecular clock framework of circadian disruption in cancer development and progression. Mouse models are the most widely used in circadian studies due to their relatively small size, fast reproduction cycle, easy genome manipulation, and economic practicality. Here, we reviewed the current mouse models of circadian disruption, including suprachiasmatic nuclei destruction, genetic engineering, light disruption, sleep deprivation, and other lifestyle factors in our understanding of the crosstalk between circadian rhythms and oncogenic signaling, as well as the molecular mechanisms of circadian disruption that promotes cancer growth. We focused on the discoveries made with the nocturnal mouse, diurnal human being, and cell culture and provided several circadian rhythm-based cancer therapeutic strategies.

Colonic Epithelial Circadian Disruption Worsens Dextran Sulfate Sodium-Induced Colitis

BACKGROUND

Disruption of central circadian rhythms likely mediated by changes in microbiota and a decrease in gut-derived metabolites like short chain fatty acids (SCFAs) negatively impacts colonic barrier homeostasis. We aimed to explore the effects of isolated peripheral colonic circadian disruption on the colonic barrier in a mouse model of colitis and explore the mechanisms, including intestinal microbiota community structure and function.

METHODS

Colon epithelial cell circadian rhythms were conditionally genetically disrupted in mice: TS4Cre-BMAL1lox (cBMAL1KO) with TS4Cre as control animals. Colitis was induced through 5 days of 2% dextran sulfate sodium (DSS). Disease activity index and intestinal barrier were assessed, as were fecal microbiota and metabolites.

RESULTS

Colitis symptoms were worse in mice with peripheral circadian disruption (cBMAL1KO). Specifically, the disease activity index and intestinal permeability were significantly higher in circadian-disrupted mice compared with control animals (TS4Cre) (P < .05). The worsening of colitis appears to be mediated, in part, through JAK (Janus kinase)-mediated STAT3 (signal transducer and activator of transcription 3), which was significantly elevated in circadian-disrupted (cBMAL1KO) mice treated with DSS (P < .05). Circadian-disrupted (cBMAL1KO) mice also had decreased SCFA metabolite concentrations and decreased relative abundances of SCFA-producing bacteria in their stool when compared with control animals (TS4Cre).

CONCLUSIONS

Disruption of intestinal circadian rhythms in colonic epithelial cells promoted more severe colitis, increased inflammatory mediators (STAT3 [signal transducer and activator of transcription 3]), and decreased gut microbiota-derived SCFAs compared with DSS alone. Further investigation elucidating the molecular mechanisms behind these findings could provide novel circadian directed targets and strategies in the treatment of inflammatory bowel disease.

Complex physiology and clinical implications of time-restricted eating

Time-restricted eating (TRE) is a dietary intervention that limits food consumption to a specific time window each day. The effect of TRE on body weight and physiological functions has been extensively studied in rodent models, which have shown considerable therapeutic effects of TRE and important interactions among time of eating, circadian biology, and metabolic homeostasis. In contrast, it is difficult to make firm conclusions regarding the effect of TRE in people because of the heterogeneity in results, TRE regimens, and study populations. In this review, we 1) provide a background of the history of meal consumption in people and the normal physiology of eating and fasting; 2) discuss the interaction between circadian molecular metabolism and TRE; 3) integrate the results of preclinical and clinical studies that evaluated the effects of TRE on body weight and physiological functions; 4) summarize other time-related dietary interventions that have been studied in people; and 4) identify current gaps in knowledge and provide a framework for future research directions.

Behavioral circadian phenotypes are associated with the risk of elevated body mass index

BACKGROUND

Metabolic dysfunction and obesity rates are on the rise. Although the central modes of circadian disruption has been studied in relation to the risk of obesity, the role of eating time has remained unclear. Here, we aimed to assess circadian behavioral phenotypes and their association with the risk of elevated body mass index (BMI).

METHODS

This was a prospective cross-sectional study of individuals presenting for colorectal cancer screening colonoscopy. Participants completed demographic questionnaires, The Munich ChronoType Questionnaire (MCTQ), and Food Timing Screener (FTS). The primary outcome of the study was the association between circadian phenotypes and elevated BMI.

RESULTS

A total of 488 individuals completed the survey, with a mean (SD) age of 57.5 (10.8) years. The mean body mass index (BMI) was 28.8 (6.1) kg/m², with 72.3% of individuals met criteria for elevated BMI. Four circadian behavioral phenotypes were generated: early chronotype with regular food timing (ER) (34.7%), early chronotype with irregular food timing (EI) (11.7%), intermediate/late chronotype with regular food timing (LR) (33.9%), and intermediate/late chronotype with irregular food timing (LI) (19.7%). In a multivariable regression analysis, LI phenotype had 2.9 times higher odds of elevated BMI as compared to ER phenotype (OR 2.9, 95% CI 1.3-6.7, P = 0.01).

CONCLUSION

The combination of late chronotype and irregular food timing, representative of a behavioral circadian rhythm disruption, is associated with higher rates of elevated BMI. The majority of individuals with this abnormal circadian phenotype were younger than 60 years old. This observation is especially relevant because of the ongoing rise in the obesity rates among young adults.

LEVEL III

Evidence obtained from well-designed cohort or case-control analytic studies.

Gut microbiota and immunity relevance in eubiosis and dysbiosis

Human gut is colonized by numerous microorganisms, in which bacteria present the highest proportion of this colonization that live in a symbiotic relationship with the host. This microbial collection is commonly known as the microbiota. The gut microbiota can mediate gut epithelial and immune cells interaction through vitamins synthesis or metabolic products. The microbiota plays a vital role in growth and development of the main components of human’s adaptive and innate immune system, while the immune system regulates host-microbe symbiosis. On the other hand, negative alteration in gut microbiota composition or gut dysbiosis, can disturb immune responses. This review highlights the gut microbiota-immune system cross-talk in both eubiosis and dysbiosis.

Novel role of the Mu-opioid receptor in pancreatic cancer: potential link between opioid use and cancer progression

Opioids are the most popular drugs for both acute and chronic pain management. The G protein-coupled mu-opioid receptor (MOR) is the therapeutic target for most clinically used opioids, including morphine. A mounting number of publications suggest a relationship between the MOR and possible cancer progression and recurrence extending to managing chronic cancer pain. In this study, we studied the possible link between opioid use and pancreatic cancer (PC) progression. We found increased MOR expression in murine and human PC cell lines, human PC-derived organoids, and in the undifferentiated or poorly differentiated areas of surgically resected PC tissues. Direct stimulation of MOR by morphine (MOR agonist) caused a significant dose-dependent increase in proliferation, invasion, and levels of stemness markers in PC cells. In a co-culture system, MOR stimulation of macrophages also resulted in increased proliferation of PC cells. MOR overexpression increased proliferation and cancer stemness, whereas knock-down of MOR followed opposite results in the PC cells. Morphine induced chemoresistance to conventional chemotherapeutic agents used for PC treatment. Overall, our results suggest that MOR is expressed in pancreatic cancer and may be involved in tumor progression and chemoresistance.

Inconsistent eating time is associated with obesity: A prospective study

Obesity is characterized by an accumulation of redundant body fat linked to metabolic dysregulation and low-grade systemic inflammation. Lifestyle choices are imperative determining factors of obesity. The contemporary lifestyle is associated with behaviors that disrupt circadian rhythms, impacting metabolic homeostasis. Our animal and human studies suggest that circadian phenotypes could be related to the risk of metabolic dysregulation and obesity. The purpose of this study is to examine the role of inconsistent eating habits on body weight in adults. Individuals who presented for colon cancer screening were enrolled. Subjects received structured questionnaires to capture 7-day eating and sleeping times in a week prospectively. Bodyweight and height were extracted from medical records, and Body Mass Index (BMI) was calculated. Inconsistent eating times were defined as an average difference of >2 hours between the largest meal on weekdays and weekends. Forty-nine of the 61 (80.3 %) individuals enrolled in the study completed the questionnaires. The mean age and standard deviation (SD) were 60.8 (7.9), and 27 (55.1 %) were male. Subjects with inconsistent eating times had a significantly higher BMI (33.8 ± 3.6 SD, n = 9) than subjects who did not (27.5 ± 6.5 SD, n = 40; p = 0.001). The highest BMI was observed in subjects who ate inconsistently and late (35.8 ± 4.6 SD). In this cross-sectional study, time of eating habits was associated with BMI. Controlled cohort studies are needed to determine the potential link between eating time and the risk of obesity in the long term.

Unrestrained eating behavior and risk of mortality: A prospective cohort study

BACKGROUND & AIMS

Unrestrained eating behavior has been thought to be a proxy for diet frequency, timing, and caloric intake. We investigated the association of unrestrained eating with mortality risk in the Nurses' Health Study prospectively.

METHODS

During follow-up (1994-2016), 21,953 deaths were documented among 63,999 eligible participants in analyses of eating anything at any time, 22,120 deaths were documented among 65,839 participants in analyses of no concern with figure change. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards models.

RESULTS

Eating anything at any time was associated with an increased mortality from cancer (overall HR, 95%CI: 1.07, 1.00-1.13; driven by gastrointestinal tract cancer: 1.30, 1.10-1.54) and respiratory disease (1.16, 1.05-1.29), and decreased cardiovascular disease-specific mortality (0.92, 0.86-0.99), compared to those without this behavior; however, no association was observed between this behavior and all-cause mortality (1.02, 0.99-1.05). Women who reported having no concern with figure change experienced higher risk of mortality from all-cause (1.08, 1.05-1.11), cancer (1.08, 1.02-1.14), and respiratory disease (1.18, 1.08-1.30), compared to those not reporting this behavior. Their combined effect was associated with a higher all-cause (1.09, 1.04-1.14), cancer-specific (overall: 1.18, 1.09-1.28; gastrointestinal tract cancer: 1.36, 1.08-1.71; lung cancer: 1.09; 1.04-1.14), and respiratory disease-specific (1.30, 1.13-1.50) mortality, and was inversely associated with cardiovascular disease-specific mortality (0.88, 0.80-0.98), compared to those exhibiting the opposite.

CONCLUSIONS

Unrestrained eating was associated with increased risk of all-cause, cancer-specific (particularly for gastrointestinal tract cancer and lung cancer), and respiratory disease-specific mortality, and decreased risk of cardiovascular disease-specific mortality.

Unrestrained eating behavior and risk of digestive system cancers: a prospective cohort study

BACKGROUND

Unrestrained eating behavior, as a potential proxy for diet frequency, timing, and caloric intake, has been questioned as a plausible risk factor for digestive system cancers, but epidemiological evidence remains sparse.

OBJECTIVES

We investigated prospectively the associations between unrestrained eating behavior and digestive system cancer risk.

METHODS

Participants in the Nurses' Health Study who were free of cancer and reported dietary information in 1994 were followed for ≤18 y. Cox models were used to estimate HRs and 95% CIs for unrestrained eating (eating anything at any time, no concern with figure change, or both) and risk of digestive system cancers.

RESULTS

During follow-up, 2064 digestive system cancer cases were documented among 70,450 eligible participants in analyses of eating anything at any time, In total, 2081 digestive system cancer cases were documented among 72,468 eligible participants in analyses of no concern with figure change. In fully adjusted analyses, women with the behavior of eating anything at any time had a higher risk of overall digestive system cancer (HR: 1.22; 95% CI: 1.10, 1.35), overall gastrointestinal tract cancer ((HR: 1.33; 95% CI: 1.18, 1.50), buccal cavity and pharynx cancer (HR: 1.50; 95% CI: 1.02, 2.21), esophageal cancer (HR: 1.62; 95% CI: 1.01, 2.62), small intestine cancer (HR: 1.92; 95% CI: 1.02,3. 59), and colorectal cancer (HR: 1.20; 95% CI: 1.04, 1.38), and a non-statistically significant increased risk of stomach cancer (HR: 1.54; 95% CI: 0.96,2.48), compared with women without this behavior. No statistically significant association was observed for pancreatic cancer and liver and gallbladder cancer. The combined effect of eating anything at any time and having no concern with figure change was associated with a significantly increased risk of overall digestive system cancer (HR: 1.27; 95% CI: 1.10, 1.46), overall gastrointestinal tract cancer (HR: 1.45; 95% CI: 1.23, 1.71), and colorectal cancer (HR: 1.34; 95% CI: 1.11, 1.63), compared with women exhibiting the opposite.

CONCLUSIONS

Unrestrained eating behavior was independently associated with increased risk of gastrointestinal tract cancers. The potential importance of unrestrained eating behavior modification in preventing gastrointestinal tract cancers should be noted.

Does chronic inflammation cause acute inflammation to spiral into hyper-inflammation in a manner modulated by diet and the gut microbiome, in severe Covid-19?

We propose that hyper-inflammation (HYPi) is a ''runaway'' consequence of acute inflammation (ACUi) that arises more easily (and also abates less easily) in those who host a pre-existing chronic inflammation (CHRi), because (i) most factors involved in generating an ACUi to limit viral proliferation are already present when there is an underlying CHRi, and also because (ii) anti-inflammatory (AI) mechanisms for the abatement of ACUi (following containment of viral proliferation) are suppressed and desensitized where there is an underlying CHRi, with this causing the ACUi to spiral into a HYPi. Stress, pollution, diet, and gut microbiomes (alterable in weeks through dietary changes) have an intimate and bidirectional cause-effect relationship with CHRi. We propose that avoidance of CHRi-promoting foods and adoption of CHRi-suppressing foods could reduce susceptibility to HYPi, in Covid-19 and in other viral diseases, such as influenza, which are characterized by episodic and unpredictable HYPi.

Exploring the link between chronobiology and drug delivery: effects on cancer therapy

Circadian clock is an impressive timing system responsible for the control of several metabolic, physiological and behavioural processes. Nowadays, the connection between the circadian clock and cancer occurrence and development is consensual. Therefore, the inclusion of circadian timing into cancer therapy may potentially offer a more effective and less toxic approach. This way, chronotherapy has been shown to improve cancer treatment efficacy. Despite this relevant finding, its clinical application is poorly exploited. The conception of novel anticancer drug delivery systems and the combination of chronobiology with nanotechnology may provide a powerful tool to optimize cancer therapy, instigating the incorporation of the circadian timing into clinical practice towards a more personalized drug delivery. This review focuses on the recent advances in the field of cancer chronobiology, on the link between cancer and the disruption of circadian rhythms and on the promising targeted drug nanodelivery approaches aiming the clinical application of cancer chronotherapy.

The circadian clock gene PER2 enhances chemotherapeutic efficacy in nasopharyngeal carcinoma when combined with a targeted nanosystem

Treatment failure occurs in more than 40% of advanced nasopharyngeal carcinoma (NPC) patients including local recurrence and distant metastasis due to chemoradioresistance. Circadian clock genes were identified as regulating cancer progression and chemoradiosensitivity in a time-dependent manner. A novel nanosystem can ensure the accumulation and controllable release of chemotherapeutic agents at the tumour site at a set time. In this study, we investigated the expression of circadian clock genes and identified that period circadian regulator 2 (PER2) as a tumour suppressor plays a key role in NPC progression. A label-free proteomic approach showed that PER2 overexpression can inhibit the ERK/MAPK pathway. The chemotherapeutic effect of PER2 overexpression was assessed in NPC together with the nanosystem comprising folic acid (FA), upconverting nanoparticles covalently coupled with Rose Bengal (UCNPs-RB), 10-hydroxycamptothecin (HCPT) and lipid-perfluorohexane (PFH) (FURH-PFH-NPs). PER2 overexpression combined with the targeted and controlled release of nanoagents elevated chemotherapeutic efficacy in NPC, which has potential application value for the chronotherapy of tumours.

Diet-induced dysbiosis of the maternal gut microbiome in early life programming of neurodevelopmental disorders

The maternal gut microbiome plays a critical role in fetal and early postnatal development, shaping fundamental processes including immune maturation and brain development, among others. Consequently, it also contributes to fetal programming of health and disease. Over the last decade, epidemiological studies and work in preclinical animal models have begun to uncover a link between dysbiosis of the maternal gut microbiome and neurodevelopmental disorders in offspring. Neurodevelopmental disorders are caused by both genetic and environmental factors, and their interactions; however, clinical heterogeneity, phenotypic variability, and comorbidities make identification of underlying mechanisms difficult. Among environmental factors, exposure to maternal obesity in utero confers a significant increase in risk for neurodevelopmental disorders. Obesogenic diets in humans, non-human primates, and rodents induce functional modifications in maternal gut microbiome composition, which animal studies suggest are causally related to adverse mental health outcomes in offspring. Here, we review evidence linking maternal diet-induced gut dysbiosis to neurodevelopmental disorders and discuss how it could affect pre- and early postnatal brain development. We are hopeful that this burgeoning field of research will revolutionize antenatal care by leading to accessible prophylactic strategies, such as prenatal probiotics, to improve mental health outcomes in children affected by maternal diet-induced obesity.

Abnormal food timing and predisposition to weight gain: Role of barrier dysfunction and microbiota

Obesity has become a common rising health care problem, especially in "modern" societies. Obesity is considered a low-grade systemic inflammation, partly linked to leaky gut. Circadian rhythm disruption, a common habit in modern life, has been reported to cause gut barrier impairment. Abnormal time of eating, defined by eating close to or during rest time, is shown to cause circadian rhythm disruption. Here, using a non-obesogenic diet, we found that abnormal feeding time facilitated weight gain and induced metabolic dysregulation in mice. The effect of abnormal time of eating was associated with increased gut permeability, estimated by sucralose and/or lactulose ratio and disrupted intestinal barrier marker. Analysis of gut microbiota and their metabolites, as important regulators of barrier homeostasis, revealed that abnormal food timing reduced relative abundance of butyrate-producing bacteria, and the colonic butyrate level. Overall, our data supported that dysbiosis was characterized by increased intestinal permeability and decreased beneficial barrier butyrate-producing bacteria and/or metabolite to mechanistically link the time of eating to obesity. This data provides basis for noninvasive microbial-targeted interventions to improve intestinal barrier function as new opportunities for combating circadian rhythm disruption induced metabolic dysfunction.

Circadian Rhythm Disruption Influenced Hepatic Lipid Metabolism, Gut Microbiota and Promoted Cholesterol Gallstone Formation in Mice

BACKGROUND

Hepatic lipid metabolism regulates biliary composition and influences the formation of cholesterol gallstones. The genes Hmgcr and Cyp7a1, which encode key liver enzymes, are regulated by circadian rhythm-related transcription factors. We aimed to investigate the effect of circadian rhythm disruption on hepatic cholesterol and bile acid metabolism and the incidence of cholesterol stone formation.

METHODS

Adult male C57BL/6J mice were fed either a lithogenic diet (LD) only during the sleep phase (time-restricted lithogenic diet feeding, TRF) or an LD ad libitum (non-time-restricted lithogenic diet feeding, nTRF) for 4 weeks. Food consumption, body mass gain, and the incidence of gallstones were assessed. Circulating metabolic parameters, lipid accumulation in the liver, the circadian expression of hepatic clock and metabolic genes, and the gut microbiota were analyzed.

RESULTS

TRF caused a dysregulation of the circadian rhythm in the mice, characterized by significant differences in the circadian expression patterns of clock-related genes. In TRF mice, the circadian rhythms in the expression of genes involved in bile acid and cholesterol metabolism were disrupted, as was the circadian rhythm of the gut microbiota. These changes were associated with high biliary cholesterol content, which promoted gallstone formation in the TRF mice.

CONCLUSION

Disordered circadian rhythm is associated with abnormal hepatic bile acid and cholesterol metabolism in mice, which promotes gallstone formation.

Circadian rhythms and the gut microbiota: from the metabolic syndrome to cancer

The metabolic syndrome is prevalent in developed nations and accounts for the largest burden of non-communicable diseases worldwide. The metabolic syndrome has direct effects on health and increases the risk of developing cancer. Lifestyle factors that are known to promote the metabolic syndrome generally cause pro-inflammatory alterations in microbiota communities in the intestine. Indeed, alterations to the structure and function of intestinal microbiota are sufficient to promote the metabolic syndrome, inflammation and cancer. Among the lifestyle factors that are associated with the metabolic syndrome, disruption of the circadian system, known as circadian dysrhythmia, is increasingly common. Disruption of the circadian system can alter microbiome communities and can perturb host metabolism, energy homeostasis and inflammatory pathways, which leads to the metabolic syndrome. This Perspective discusses the role of intestinal microbiota and microbial metabolites in mediating the effects of disruption of circadian rhythms on human health.

Metabolite Sensing GPCRs: Promising Therapeutic Targets for Cancer Treatment?

G-protein-coupled receptors constitute the most diverse and largest receptor family in the human genome, with approximately 800 different members identified. Given the well-known metabolic alterations in cancer development, we will focus specifically in the 19 G-protein-coupled receptors (GPCRs), which can be selectively activated by metabolites. These metabolite sensing GPCRs control crucial processes, such as cell proliferation, differentiation, migration, and survival after their activation. In the present review, we will describe the main functions of these metabolite sensing GPCRs and shed light on the benefits of their potential use as possible pharmacological targets for cancer treatment.

Summary of the 2019 alcohol and immunology research interest group (AIRIG) meeting: Alcohol-mediated mechanisms of multiple organ injury

On November 15, 2019, the 24th annual Alcohol and Immunology Research Interest Group (AIRIG) meeting was held as a satellite conference during the annual Society for Leukocyte Biology meeting in Boston, Massachusetts. The 2019 meeting focused on alcohol, immunity, and organ damage, and included two plenary sessions. The first session highlighted new research exploring the mechanisms of alcohol-induced inflammation and liver disease, including effects on lipidomics and lipophagy, regulatory T cells, epigenetics, epithelial cells, and age-related changes in the gut. The second session covered alcohol-induced injury of other organs, encompassing diverse areas of research ranging from neurodegeneration, to lung barrier function, to colon carcinogenesis, to effects on viral infection. The discussions also highlighted current laboratory and clinical research used to identify biomarkers of alcohol use and disease.

Alcohol-Induced Immune Dysregulation in the Colon Is Diurnally Variable

Introduction

Alcohol increases the risk of colon cancer. Colonic inflammation mediates the effects of alcohol on colon carcinogenesis. Circadian rhythm disruption enhances the alcohol's effect on colonic inflammation and cancer.

Objective

Here, we investigate the diurnal variation of lymphocyte infiltration in the colonic mucosa in response to alcohol.

Methods

Sixty C57BL6/J mice were fed a chow diet, and gavaged with alcohol at a specific time once per day for 3 consecutive days. Immunohistochemistry and immunofluorescence staining were used to quantify total, effector, and regulatory T cells in the colon. Student's t test, one-way ANOVA, and two-way ANOVA were used to determine significance.

Results

Following the alcohol binge, the composition of immune T cell subsets in the mouse colon was time-dependent. Alcohol did not alter the total number of CD3⁺ T cells. However, upon alcohol treatment, T-bet⁺ T helper 1 (Th1) cells appeared to dominate the T cell population following a reduction in Foxp3⁺ regulatory T cell (Treg) numbers. Depletion of Tregs was time-dependent, and their numbers were dramatically reduced when alcohol was administered during the rest phase. A reduction in Tregs significantly increased the Th1/Treg ratio, resulting in a more proinflammatory milieu.

Conclusions

Alcohol enhanced the proinflammatory profile in the colon mucosa, as demonstrated by a higher T-bet⁺/Foxp3⁺ ratio, especially during the rest phase. These findings may partly account for the interaction of circadian rhythm disruption with alcohol in colon inflammation and cancer.

Microglia, inflammation and gut microbiota responses in a progressive monkey model of Parkinson's disease: A case series

Inflammation has been linked to the development of nonmotor symptoms in Parkinson's disease (PD), which greatly impact patients' quality of life and can often precede motor symptoms. Suitable animal models are critical for our understanding of the mechanisms underlying disease and the associated prodromal disturbances. The neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkey model is commonly seen as a "gold standard" model that closely mimics the clinical motor symptoms and the nigrostriatal dopaminergic loss of PD, however MPTP toxicity extends to other nondopaminergic regions. Yet, there are limited reports monitoring the MPTP-induced progressive central and peripheral inflammation as well as other nonmotor symptoms such as gastrointestinal function and microbiota. We report 5 cases of progressive parkinsonism in non-human primates to gain a broader understanding of MPTP-induced central and peripheral inflammatory dysfunction to understand the potential role of inflammation in prodromal/pre-motor features of PD-like degeneration. We measured inflammatory proteins in plasma and CSF and performed [¹⁸F]FEPPA PET scans to evaluate translocator proteins (TSPO) or microglial activation. Monkeys were also evaluated for working memory and executive function using various behavior tasks and for gastrointestinal hyperpermeability and microbiota composition. Additionally, monkeys were treated with a novel TNF inhibitor XPro1595 (10 mg/kg, n = 3) or vehicle (n = 2) every three days starting 11 weeks after the initiation of MPTP to determine whether XPro1595 would alter inflammation and microglial behavior in a progressive model of PD. The case studies revealed that earlier and robust [¹⁸F]FEPPA PET signals resulted in earlier and more severe parkinsonism, which was seen in male cases compared to female cases. Potential other sex differences were observed in circulating inflammation, microbiota diversity and their metabolites. Additional studies with larger group sizes of both sexes would enable confirmation and extension of these findings. If these findings reflect potential differences in humans, these sex differences have significant implications for therapeutic development of inflammatory targets in the clinic.

Abnormal Food Timing Promotes Alcohol-Associated Dysbiosis and Colon Carcinogenesis Pathways

Background: Alcohol consumption is an established risk factor for colorectal cancer (CRC). Identifying cofactor(s) that modulate the effect of alcohol on colon inflammation and carcinogenesis could help risk stratification for CRC. Disruption of circadian rhythm by light/dark shift promotes alcohol-induced colonic inflammation and cancer. More recently, we found that abnormal food timing causes circadian rhythm disruption and promotes alcohol associated colon carcinogenesis. In this study, we examined the interaction of wrong-time feeding (WTF) and alcohol on CRC-related pathways, in relation to changes in microbial community structure. Methods: Polyposis mice (TS4Cre ×cAPC Δ468) underwent four conditions: alcohol or water and feeding during the light (wrong-time fed/WTF) or during the dark (right-time fed). Colonic cecum mucosal gene expression was analyzed by RNA-seq. Microbiota 16S ribosomal RNA sequencing analysis was used to examine colonic feces. Modeling was used to estimate the extent of the gene expression changes that could be related to the changes in the colonic microbial composition. Results: The circadian rhythm pathway was the most altered pathway by the WTF treatment, indicating that WTF is disruptive to the colonic circadian rhythm. Pathway analysis revealed interaction of WTF with alcohol in dysregulating pathways related to colon carcinogenesis. Similarly, the interaction of alcohol and WTF was detected at multiple parameters of the colonic microbiota including α and β diversity, as well as the community structure. Our modeling revealed that almost a third of total gene alterations induced by our treatments could be related to alterations in the abundance of the microbial taxa. Conclusion: These data support the promoting effect of abnormal food timing alcohol-associated CRC-related pathways in the colon and suggest colon dysbiosis as a targetable mechanism.

Spotlight on Circadian Genes and Colorectal Cancer Crosstalk

Mammalian physiology is regulated by circadian clock through oscillating feedback loops controlling cellular processes and behaviors. Recent findings have led to an interesting connection between circadian disruption and colorectal cancer progression and incidence through controlling the hallmarks of cancer, namely cell cycle, cell metabolism and cell death. Deeper understanding of the circadian mechanisms that define the colorectal cancer pathophysiology is the need of the hour to define a chronotherapy for improving colorectal cancer patient survival. This review identifies the key areas in which circadian genes interact with cellular pathways to modify the outcome with respect to colorectal cancer incidence and progression.

Interaction between microbiota and immunity in health and disease

The interplay between the commensal microbiota and the mammalian immune system development and function includes multifold interactions in homeostasis and disease. The microbiome plays critical roles in the training and development of major components of the host's innate and adaptive immune system, while the immune system orchestrates the maintenance of key features of host-microbe symbiosis. In a genetically susceptible host, imbalances in microbiota-immunity interactions under defined environmental contexts are believed to contribute to the pathogenesis of a multitude of immune-mediated disorders. Here, we review features of microbiome-immunity crosstalk and their roles in health and disease, while providing examples of molecular mechanisms orchestrating these interactions in the intestine and extra-intestinal organs. We highlight aspects of the current knowledge, challenges and limitations in achieving causal understanding of host immune-microbiome interactions, as well as their impact on immune-mediated diseases, and discuss how these insights may translate towards future development of microbiome-targeted therapeutic interventions.

Interaction between microbiota and immunity in health and disease

The interplay between the commensal microbiota and the mammalian immune system development and function includes multifold interactions in homeostasis and disease. The microbiome plays critical roles in the training and development of major components of the host's innate and adaptive immune system, while the immune system orchestrates the maintenance of key features of host-microbe symbiosis. In a genetically susceptible host, imbalances in microbiota-immunity interactions under defined environmental contexts are believed to contribute to the pathogenesis of a multitude of immune-mediated disorders. Here, we review features of microbiome-immunity crosstalk and their roles in health and disease, while providing examples of molecular mechanisms orchestrating these interactions in the intestine and extra-intestinal organs. We highlight aspects of the current knowledge, challenges and limitations in achieving causal understanding of host immune-microbiome interactions, as well as their impact on immune-mediated diseases, and discuss how these insights may translate towards future development of microbiome-targeted therapeutic interventions.