Maintain host health with time-restricted eating and phytochemicals: A review based on gut microbiome and circadian rhythm

A scenario of unhealthy life cycle: The role of circadian rhythms in health

Circadian rhythms are oscillations in physiology and behavior caused by the circadian regulator. Cryptochromes, Periods, and Bmal1 are circadian clock genes that have been linked to aging and cancer. Human pathologies alter circadian clock gene expression, and transgenic rats with clock gene defects progress to cancer and age prematurely. In the growth of age-linked pathologies and carcinogenesis, cell proliferation and genome integrity play critical roles. The relationship concerning the cell cycle regulation and circadian clock is discussed in this article. The circadian clock controls the behavior and countenance of many main cell cycle and cell cycle check-point proteins, and cell cycle-associated proteins, in turn, control the activity and expression of circadian clock proteins. The circadian clock can be reset by DNA disruption, providing a molecular mechanism for mutual control amid the cell cycle and the clock. This circadian clock-dependent regulation of cell proliferation, composed with other circadian clock-dependent physiological functions including metabolism control, genotoxic and oxidative stress response, and DNA repair, unlocks new avenues for studying the processes of aging and carcinogenesis.

Piperine Improves Lipid Dysregulation by Modulating Circadian Genes Bmal1 and Clock in HepG2 Cells

Metabolic disorders are closely associated with the dysregulation of circadian rhythms. Many bioactive components with lipid metabolism-regulating effects have been reported to function through circadian clock-related mechanisms. As the main pungent principle of black pepper, piperine (PIP) has been demonstrated to possess anti-obesity bioactivity by affecting hepatic lipid metabolism-related factors. However, whether the circadian clock genes Bmal1 and Clock are involved in the protective effect of PIP against lipid metabolism disorders remains unknown. In this work, oleic acid (OA) induced lipid accumulation in HepG2 cells. The effect of PIP on redox status, mitochondrial functions, and circadian rhythms of core clock genes were evaluated. Results revealed that PIP alleviated circadian desynchrony, ROS overproduction, and mitochondrial dysfunction. A mechanism study showed that PIP could activate the SREBP-1c/PPARγ and AMPK/AKT-mTOR signaling pathways in a Bmal1/Clock-dependent manner in HepG2 cells. These results indicated that Bmal1 and Clock played important roles in the regulating effect of PIP on hepatic lipid homeostasis.

Mechanisms Underlying the Interaction Between Chronic Neurological Disorders and Microbial Metabolites via Tea Polyphenols Therapeutics

The number of hydroxyl groups and existence of characteristic structural groups in tea polyphenols (TP) make them have antioxidant activity, which gives TP anti-inflammatory effects, toward protecting the intestinal flora and brain neurons. Host-associated microbial metabolites are emerging as dominant modifiers of the central nervous system. As yet, the investigations on host-microbiota crosstalking remain challenging, studies focusing on metabolites such as serotonin, short-chain fatty acids, and others have pinpointed multiple actionable signaling pathways relevant to host health. However, there are still complexities and apparent limitations inherent in transforming complex human diseases to corresponding animal models. Here, we choose to discuss several intestinal metabolites with research value, as crucial areas for assessing TP-mediated chronic brain diseases interactions with microbial.

Tea combats circadian rhythm disorder syndrome via the gut-liver-brain axis: potential mechanisms speculated

Circadian rhythm is an intrinsic mechanism developed by organisms to adapt to external environmental signals. Nowadays, owing to the job and after-work entertainment, staying up late - Circadian rhythm disorders (CRD) are common. CRD is linked to the development of fatty liver, type 2 diabetes, and chronic gastroenteritis, which affecting the body's metabolic and inflammatory responses via multi-organ crosstalk (gut-liver-brain axis, etc.). However, studies on the mechanisms of multi-organ interactions by CRD are still weak. Current studies on therapeutic agents for CRD remain inadequate, and phytochemicals have been shown to alleviate CRD-induced syndromes that may be used for CRD-therapy in the future. Tea, a popular phytochemical-rich beverage, reduces glucolipid metabolism and inflammation. But it is immature and unclear in the mechanisms of alleviation of CRD-mediated syndrome. Here, we have analyzed the threat of CRD to hosts and their offspring' health from the perspective of the "gut-liver-brain" axis. The potential mechanisms of tea in alleviating CRD were further explored. It might be by interfering with bile acid metabolism, tryptophan metabolism, and G protein-coupled receptors, with FXR, AHR, and GPCR as potential targets. We hope to provide new perspectives on the role of tea in the prevention and mitigation of CRD.HighlightsThe review highlights the health challenges of CRD via the gut-liver-brain axis.CRD research should focus on the health effects on healthy models and its offspring.Tea may prevent CRD by regulating bile acid, tryptophan, and GPCR.Potential targets for tea prevention and mitigation of CRD include FXR, AHR and GPCR.A comprehensive assessment mechanism for tea in improving CRD should be established.

The interaction effect between tea polyphenols and intestinal microbiota: Role in ameliorating neurological diseases

Tea polyphenols (TP) are one of the most functional and bioactive substances in tea. The interactions between TP and intestinal microbiota suggest that probiotics intervention is a useful method to ameliorate neurological diseases. Now, numerous researches have suggested that TP plays a significant role in modulating intestinal bacteria, especially in the area of sustaining a stable state of intestinal microbial function and abundance. Furthermore, homeostatic intestinal bacteria can enhance the immunity of the host. The close reciprocity between intestinal microbiota and the central nervous system provides a new chance for TP to modulate neural-related diseases depending on intestinal microbiota. Therefore, based on the bidirectional relationship between the brain and the intestines, this review provides a new clue to solve insomnia symptoms and related neurological diseases that will enable us to better study the bidirectional effects of TP and intestinal microbiota on the improvement of host health. PRACTICAL APPLICATIONS: This review provides a new clue to solve insomnia symptoms and related neurological diseases that will enable us to better study bidirectional effects of TP and intestinal microbiota on the improvement of host health.

Health benefits of dietary chronobiotics: beyond resynchronizing internal clocks

The internal circadian clock in mammals drives whole-body biological activity rhythms. The clock reflects changes in external signals by controlling enzyme functions and the release of hormones involved in metabolic processes. Thus, misalignments between the circadian clock and an individual's daily schedule are recognized to be related to various metabolic diseases, such as obesity and diabetes. Although evidence has shown the existence of a complex relationship between circadian clock regulation and daily food intake, the regulatory effects of phytochemicals on the circadian clock remain unclarified. To better elucidate these relationships/effects, the circadian system components in mammals, circadian misalignment-related metabolic diseases, circadian rhythm-adjusting phytochemicals (including the heterocycles, acids, flavonoids and others) and the potential mechanisms (including the regulation of clock genes/proteins, metabolites of gut microbiota and secondary metabolites) are reviewed here. The bioactive components of functional foods discussed in this review could be considered potentially effective factors for the prevention and treatment of metabolic disorders related to circadian misalignment.