Whether we are aware or not, diverse microorganisms are living on almost all environmentally exposed surfaces on our body without eliciting harmful immune responses. In fact, recent understanding from numerous studies indicates that our health is highly dependent on the contribution of intestinal commensal bacteria. It appears through its symbiotic interaction with the host, which is the result of millions of years of co-evolution, the microbiota shapes the immune system. In this review, we discuss the relationship between host physiology and commensal bacteria and explore the molecular mechanisms by which the adaptive immune system is influenced by the intestinal microbiota.
Bacteria ; Dysbiosis ; Immune System* ; Microbiota* ; Physiology

With the development of intestinal flora, short chain fatty acid(SCFA), produced by the intestinal microbiota, has been found to be important for the host. It also plays an important role in the part of the occurrence and development of some diseases. The relationship between SCFA produced by intestinal microbiota and the host body has become the research focus in recent years. The physiological function and clinical application of SCFA were reviewed in this article.
Fatty Acids, Volatile ; biosynthesis ; physiology ; Humans ; Intestines ; microbiology ; Microbiota

Co-culture systems consisted of photosynthetic microorganisms and others heterotrophic microbes have attracted great attention in recent years. These systems show many advantages when compared with single culture grown under autotrophic conditions, such as less vulnerable to pollution and more stability, thus have been applied to wastewater treatment, soil remediation, biodegradable harmful substances, and production of high value-added products. In order to explore basic theory and further applications, we summarize here recent progresses in artificial co-culture systems of using photosynthetic microorganisms, to provide a current scientific understanding for the rational design of the co-culture system based on photosynthetic microorganisms using synthetic biology.
Coculture Techniques ; Heterotrophic Processes ; Microbiological Techniques ; trends ; Microbiota ; physiology ; Photosynthesis ; physiology ; Synthetic Biology ; trends

A cure for type 2 diabetes was once a mere dream but has now become a tangible and achievable goal with the unforeseen success of bariatric surgery in the treatment of both obesity and type 2 diabetes. Popular bariatric procedures such as Roux-en-Y gastric bypass and sleeve gastrectomy exhibit high rates of diabetes remission or marked improvement in glycemic control. However, the mechanism of diabetes remission following these procedures is still elusive and appears to be very complex and encompasses multiple anatomical and physiological changes. In this article, calorie restriction, improved beta-cell function, improved insulin sensitivity, and alterations in gut physiology, bile acid metabolism, and gut microbiota are reviewed as potential mechanisms of diabetes remission after Roux-en-Y gastric bypass and sleeve gastrectomy.
Bariatric Surgery* ; Bile ; Diabetes Mellitus, Type 2 ; Gastrectomy ; Gastric Bypass ; Insulin Resistance ; Metabolism ; Microbiota ; Obesity ; Physiology

Human physiology and pathology can be affected by different nutritional conditions. At cellular level, the availability of a nutritional component not only mediates metabolic reactions but also transmits signals for diverse biological activities. Epigenetic regulation such as DNA methylation and histone post-translational modifications is considered as one of the nutrient-mediated signaling receivers as almost all of the epigenetic enzyme activities require intermediary metabolites as cofactors. The gut microbiome as “forgotten organ” has been suggested as a metabolite generator as well as a nutrient sensor for its host organism, affecting human health and diseases. Given the metabolite-dependent activities of epigenetic regulators, the gut microbiome has a high potential to influence the epigenetics in human physiology. Here, I review the involvement of gut microbiome in diverse human diseases and the mechanisms of epigenetic regulation by different metabolites. Thereafter, I discuss how the gut microbiome-generated metabolites affect host epigenetics, raising a possibility to develop a therapeutic intervention based on the interaction between the microbiome and epigenetics for human health.
DNA Methylation ; Epigenomics* ; Gastrointestinal Microbiome* ; Histones ; Humans* ; Metabolism ; Microbiota ; Pathology ; Physiology ; Protein Processing, Post-Translational

Complex communities of microorganisms, termed commensal microbiota, inhabit mucosal surfaces and profoundly influence host physiology as well as occurrence of allergic diseases. Perturbing factors such as the mode of delivery, dietary fibers and antibiotics can influence allergic diseases by altering commensal microbiota in affected tissues as well as in intestine. Here, we review current findings on the relationship between commensal microbiota and allergic diseases, and discuss the underlying mechanisms that contribute to the regulation of allergic responses by commensal microbiota.
Anti-Bacterial Agents ; Asthma ; Dermatitis, Atopic ; Dietary Fiber ; Food Hypersensitivity ; Hygiene* ; Intestines ; Microbiota* ; Physiology

Microbes appear in every corner of human life, and microbes affect every aspect of human life. The human oral cavity contains a number of different habitats. Synergy and interaction of variable oral microorganisms help human body against invasion of undesirable stimulation outside. However, imbalance of microbial flora contributes to oral diseases and systemic diseases. Oral microbiomes play an important role in the human microbial community and human health. The use of recently developed molecular methods has greatly expanded our knowledge of the composition and function of the oral microbiome in health and disease. Studies in oral microbiomes and their interactions with microbiomes in variable body sites and variable health condition are critical in our cognition of our body and how to make effect on human health improvement.
Human Body ; Humans ; Microbiota ; physiology ; Mouth ; microbiology ; Mouth Diseases ; microbiology ; therapy

In the last decade, it has become increasingly recognized that a balanced gut microbiota plays an important role in maintaining the health of the host. Numerous clinical and preclinical studies have shown that changes in gut microbiota composition are associated with a variety of neurological diseases, e.g., Parkinson's disease, Alzheimer's disease, and myasthenia gravis. However, the underlying molecular mechanisms are complex and remain unclear. Behavioral phenotypes can be transmitted from humans to animals through gut microbiota transplantation, indicating that the gut microbiota may be an important regulator of neurological diseases. However, further research is required to determine whether animal-based findings can be extended to humans and to elucidate the relevant potential mechanisms by which the gut microbiota regulates neurological diseases. Such investigations may aid in the development of new microbiota-based strategies for diagnosis and treatment and improve the clinical management of neurological disorders. In this review, we describe the dysbiosis of gut microbiota and the corresponding mechanisms in common neurological diseases, and discuss the potential roles that the intestinal microbiome may play in the diagnosis and treatment of neurological disorders.
Animals ; Humans ; Gastrointestinal Microbiome/physiology* ; Nervous System Diseases ; Parkinson Disease ; Microbiota ; Brain

Alcoholic liver disease is a leading cause of morbidity and liver-related death worldwide. Intestinal bacterial overgrowth and dysbiosis induced by ethanol ingestion play an important role in the pathogenesis of alcoholic liver disease. After exposure to alcohol in the lumen, enteric bacteria alter their metabolism and thereby disturb intestinal homeostasis. Disruption of the mucosal barrier results in the translocation of microbial products that contribute to liver disease by inducing hepatic inflammation. In this review, we will discuss the effects of alcohol on the intestinal microbiome, and in particular, its effects on bacterial metabolism, bacterial translocation and ecological balance. A better understanding of the interactions among alcohol, the host and the microbiome will reveal new targets for therapy and lead to new treatments.
Bacterial Translocation/physiology ; Central Nervous System Depressants/metabolism ; Ethanol/metabolism ; Humans ; Intestines/*microbiology ; Lipopolysaccharides/physiology ; Liver Diseases, Alcoholic/*microbiology ; Microbiota/*physiology ; Permeability

Microorganisms coexist in the human body and its function is essential to maintain normal physiology and homeostasis. Microbiota refers to the entire population of microorganisms that colonizes a particular location; includes not just bacteria but also other microbes. Gut microbiota is vast and complex. It could be changed dynamically according to the variable factors. Well balanced host-microbial symbiotic state is a harmonious ecosystem in the stable individual. But, dysbiosis is a state of deviation in composition or function from the usual gut microbiota. It has been found that this condition is associated with many gastrointestinal, metabolic, allergic and the other diseases. Dysbiosis plays an important role in the pathophysiology of functional bowel disease, such as irritable bowel syndrome and functional constipation. Probiotics is microorganism which, when administrated in adequate amounts, confer a health benefit on the host. Probiotics have beneficial effects to reduce several symptoms of functional bowel diseases. Currently, complementary and alternative medicine therapies with probiotics is recommended for symptomatic relief from functional bowel disease.
Bacteria ; Colon ; Complementary Therapies ; Constipation ; Dysbiosis ; Ecosystem ; Gastrointestinal Microbiome* ; Homeostasis ; Human Body ; Insurance Benefits ; Irritable Bowel Syndrome ; Microbiota ; Physiology ; Probiotics*