Therapies Aimed at the Gut Microbiota and Inflammation: Antibiotics, Prebiotics, Probiotics, Synbiotics, Anti-inflammatory Therapies

Several lines of evidence suggest that the gut microbiome may represent a valid target for new therapeutic interventions in relation to disorders of the gut–brain axis. Indeed, the concept of a microbiome–gut–brain axis has gained considerable traction in recent years. While several diseases and disorders may reflect disruption of, or dysfunction along, the microbiome–gut–brain axis this chapter will focus on one very common and challenging disorder long perceived as representing dysfunction along the gut–brain axis: irritable bowel syndrome (IBS). Recognizing the frequency with which patients report exacerbation of their IBS symptoms on eating there has been, of late considerable interest in diet in the treatment of IBS. A variety of dietary approaches have been advocated with the diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) achieving most traction. The physiological basis for its efficacy as well as evidence to support its efficacy are reviewed. While comparisons between the low FODMAP diet and other dietary approaches to IBS have yielded variable results, interest in the gluten-free diet has receded somewhat though it may be of benefit to certain select populations. Various therapeutic strategies have been employed to address gut microbial factors that may contribute to IBS and include probiotics, prebiotics, and postbiotics. With regard to prebiotics and probiotics, while a considerable volume of experimental data attests to their ability to address various pathophysiologic parameters relevant to IBS, the interpretation of clinical trials continues to pose challenges. Thus, while probiotics, in general, appear to be beneficial in IBS, less is known about ideal strain, preparation, and dosage; for prebiotics and postbiotics, data are scant but appear promising. More high-quality clinical trials are needed.

In December 2019, a pneumonia outbreak of unknown etiology was reported which caused panic in Wuhan city of central China, which was later identified as Coronavirus disease (COVID-19) caused by a novel coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) by the Chinese Centre for Disease Control and Prevention (CDC) and WHO. To date, the SARS-CoV-2 spread has already become a global pandemic with a considerable death toll. The associated symptoms of the COVID-19 infection varied with increased inflammation as an everyday pathological basis. Among various other symptoms such as fever, cough, lethargy, gastrointestinal (GI) symptoms included diarrhea and IBD with colitis, have been reported. Currently, there is no sole cure for COVID-19, and researchers are actively engaged to search out appropriate treatment and develop a vaccine for its prevention. Antiviral for controlling viral load and corticosteroid therapy for reducing inflammation seems to be inadequate to control the fatality rate. Based on the available related literature, which documented GI symptoms with diarrhea, inflammatory bowel diseases (IBD) with colitis, and increased deaths in the intensive care unit (ICU), conclude that dysbiosis occurs during SARS−COV-2 infection as the gut-lung axis cannot be ignored. As probiotics play a therapeutic role for GI, IBD, colitis, and even in viral infection. So, we assume that the inclusion of studies to investigate gut microbiome and subsequent therapies such as probiotics might help decrease the inflammatory response of viral pathogenesis and respiratory symptoms by strengthening the host immune system, amelioration of gut microbiome, and improvement of gut barrier function.

The human colon absorbs water and electrolytes stores feces until elimination is socially convenient, and salvages nutrients by bacterial metabolism of nutrients that were not absorbed in the small intestine. Colonic motility is characterized by patterned contractions of longitudinal and circular muscle layers, which result from interactions between several types of cells in the gut wall (neurons, glia, interstitial cells of Cajal, smooth muscle cells, enteroendocrine cells, resident white blood cells, and fibroblast-like cells) and which are regulated by the extrinsic nervous system. Motility is closely integrated with colonic secretion and absorption. This chapter reviews colonic motility and where possible, relates anatomy, coordinated motor patterns, and propulsion of material to their underlying cellular and molecular mechanisms. Since there are considerable interspecies differences in colonic anatomy and function, the emphasis is on colonic sensorimotor functions in health and disease in humans, supplemented by data from other species, where necessary.

Fructooligosaccharides (FOS) is a generic term of oligosaccharides with beta (2→1) fructosyl-fructose glycosidic bonds. They can be obtained either by extraction from plants or enzymatically synthesized. As one of the most widely commercially available prebiotics, the health benefits of dietary FOS in consumer's health have long been appreciated, including immune modulation, improvement of gastrointestinal condition and uptake of mineral, protection against colon cancer, and decreased risk of obesity-associated disorders. Dietary FOS have resistance to hydrolysis by human salivary and small intestinal digestive enzymes, and reach the colon structurally unchanged where they are selectively fermented by probiotics. This review focuses on the effects and mechanisms of FOS with emphasis in the potential causal relationship between the prebiotic effects and the benefits to health.

Evidence suggests that the gut microbiome represents a target for new therapeutic interventions for disorders of the gut-brain axis. The concept of a microbiome-gut-brain axis has gained considerable traction. Although several diseases and disorders may reflect disruption of, or dysfunction along, the microbiome-gut-brain axis, this chapter will focus on one very common and challenging disorder long perceived as representing dysfunction along the gut-brain axis: irritable bowel syndrome (IBS). That the microbiome may be relevant to the genesis of symptoms in IBS is supported by clinical and experimental observations. Various therapeutic strategies have been used in IBS: diet, probiotics, prebiotics, and antibiotics. With regard to probiotics, although a considerable volume of experimental data attests to their ability to address the various pathophysiologic parameters that appear relevant to IBS, the quality of clinical data is less impressive and higher quality clinical trials are needed.