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The gut microbiome and its link with human health and disease have gained a lot of attention recently. The microbiome executes its functions in the host by carrying out the transformation of dietary components and/or de novo synthesis of various essential nutrients. The presence of complex microbial communities makes it difficult to understand the host-microbiome interplay in the metabolism of dietary components. This review attempts to uncover the incredible role of the gut microbiome in the metabolism of dietary components, diet-microbiome interplay, and restoration of the microbiome. The in silico analysis performed in this study elucidates the functional description of essential/hub genes involved in the amino acid degradation pathway, which are mutually present in the host and its gut microbiome. Hence, the computational model helps comprehend the inter-and intracellular molecular networks between humans and their microbial partners. [ABSTRACT FROM AUTHOR]

Obesity and malnutrition both cause dysbiosis and dampen retinoic acid (RA) signaling pathways, which play pivotal roles in biological processes. The current study evaluates a hypothesis that colitis-associated dysbiosis also has systemic negative impacts on RA signaling. Thus, we studied the effects of inflammation, under a vitamin A-sufficient condition, on RA signaling using mouse colitis models induced by dextran sulfate sodium. That data showed that intestinal inflammation resulted in reduced RA signaling in the liver, brain, gut, and adipose tissues measured by analyzing the expression of genes encoding for the synthesis, oxidation, transport, and receptor of RA. The expression of RA-regulated gut homing molecules including α4β7 integrin, and CCR9, along with MADCAM1 were all reduced in colitis mice revealing compromised immunity due to reduced RA signaling. The data also showed that the development of colitis was accompanied by dysbiosis featured with reduced Lactobacillaceae and Verrucomicrobiaceae but an expansion of Erysipelotrichaceae and others. Colitis resulted in reduced butyrate-producing bacteria and increased methane-generating bacteria. Additionally, dysbiosis was associated with induced Il-1β, Ifn-γ, and Tnf-α mRNA but reduced Il-22, Il-17f, and Rorγt transcripts in the colon. Together, intestinal inflammation inhibits RA signaling in multiple organs. RA is essential in regulating various biological processes, it is critical to detect RA signaling reduction in tissues even when vitamin A deficiency is absent. Moreover, probiotics can potentially prevent dysbiosis and reverse compromised RA signaling, having systemic health benefits. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is the largest infectious disease with 10 million new active-TB patients and1.7 million deaths per year. Active-TB is an inflammatory disease and is increasingly viewed as an imbalance of immune responses to M. tb. infection. The mechanisms of a switch from latent infection to active disease is not well worked out but a shift in the immune responses is thought to be responsible. Increasingly, the role of gut microbiota has been described as a major influencer of the immune system. And because the gut is the largest immune organ, we aimed to analyze the gut microbiome in active-TB patients in a TB-endemic country, Pakistan. The study revealed that Ruminococcacea, Enetrobactericeae, Erysipelotrichaceae, Bifidobacterium, etc. were the major genera associated with active-TB, also associated with chronic inflammatory disease. Plasma antibody profiles against several M. tb. antigens, as specific biomarkers for active-TB, correlated closely with the patient gut microbial profiles. Besides, bcoA gene copy number, indicative of the level of butyrate production by the gut microbiome was five-fold lower in TB patients compared to healthy individuals. These findings suggest that gut health in TB patients is compromised, with implications for disease morbidity (e.g., severe weight loss) as well as immune impairment. [ABSTRACT FROM AUTHOR]

Abstract: Dysregulated bile acid (BA) synthesis or reduced farnesoid X receptor (FXR) levels are found in patients having metabolic diseases, autoimmune hepatitis, and liver cirrhosis or cancer. The objective of this study was to establish the relationship between butyrate and dysregulated BA synthesis‐induced hepatitis as well as the effect of butyrate in reversing the liver pathology. Wild‐type (WT) and FXR knockout (KO) male mice were placed on a control (CD) or western diet (WD) for 15 months. In the presence or absence of butyrate supplementation, feces obtained from 15‐month‐old WD‐fed FXR KO mice, which had severe hepatitis and liver tumors, were transplanted to 7‐month‐old WD‐fed FXR KO for 3 months. Hepatic phenotypes, microbiota profile, and BA composition were analyzed. Butyrate‐generating bacteria and colonic butyrate concentration were reduced due to FXR inactivation and further reduced by WD intake. In addition, WD‐fed FXR KO male mice had the highest concentration of hepatic β‐muricholic acid (β‐MCA) and bacteria‐generated deoxycholic acid (DCA) accompanied by serious hepatitis. Moreover, dysregulated BA and reduced SCFA signaling co‐existed in both human liver cancers and WD‐fed FXR KO mice. Microbiota transplantation using butyrate‐deficient feces derived from 15‐month‐old WD‐fed FXR KO mice increased hepatic lymphocyte numbers as well as hepatic β‐MCA and DCA concentrations. Furthermore, butyrate supplementation reduced hepatic β‐MCA as well as DCA and eliminated hepatic lymphocyte infiltration. In conclusion, reduced butyrate contributes to the development of hepatitis in the FXR KO mouse model. In addition, butyrate reverses dysregulated BA synthesis and its associated hepatitis. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Dysregulated bile acid (BA) synthesis or reduced farnesoid X receptor (FXR) levels are found in patients having metabolic diseases, autoimmune hepatitis, and liver cirrhosis or cancer. The objective of this study was to establish the relationship between butyrate and dysregulated BA synthesis-induced hepatitis as well as the effect of butyrate in reversing the liver pathology. Wild-type (WT) and FXR knockout (KO) male mice were placed on a control (CD) or western diet (WD) for 15 months. In the presence or absence of butyrate supplementation, feces obtained from 15-month-old WD-fed FXR KO mice, which had severe hepatitis and liver tumors, were transplanted to 7-month-old WD-fed FXR KO for 3 months. Hepatic phenotypes, microbiota profile, and BA composition were analyzed. Butyrate-generating bacteria and colonic butyrate concentration were reduced due to FXR inactivation and further reduced by WD intake. In addition, WD-fed FXR KO male mice had the highest concentration of hepatic β-muricholic acid (β-MCA) and bacteria-generated deoxycholic acid (DCA) accompanied by serious hepatitis. Moreover, dysregulated BA and reduced SCFA signaling co-existed in both human liver cancers and WD-fed FXR KO mice. Microbiota transplantation using butyrate-deficient feces derived from 15-month-old WD-fed FXR KO mice increased hepatic lymphocyte numbers as well as hepatic β-MCA and DCA concentrations. Furthermore, butyrate supplementation reduced hepatic β-MCA as well as DCA and eliminated hepatic lymphocyte infiltration. In conclusion, reduced butyrate contributes to the development of hepatitis in the FXR KO mouse model. In addition, butyrate reverses dysregulated BA synthesis and its associated hepatitis. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Aquaculture is one of the fastest growing food producing sectors in the world. The increase in the world population requires faster growth in aquaculture for better food availability and to overcome malnutrition. But this worldwide growth of aquaculture is overwhelmed by catastrophic fish diseases and spoilage during cultivation and preservation problems caused by pathogenic bacteria. Various remedies are available for food preservation and also from the bacterial diseases in the fish production. Due to the emergence of antibiotic resistance and adverse effects, an alternative to antibiotic is the need of the hour. The proteins such as bacteriocins, i.e. ribosomally synthesized antimicrobial peptides ( AMPs) and possess antagonistic against closely related and other bacteria. These proteins are produced by most lineages of bacteria which are playing key roles in recognition and possess a cognate immunity system for self-protection as well as host protection from infections. These proteins are potent immunomodulators with broad spectrum inhibition properties which are further used as novel therapeutic agents. In this review, we have tried to summarize the bacteriocins on the basis of their classifications, structural and functional attributes, mode of actions, bacteriocins isolated from fish and gut microbiota and presence of beneficiary bacteria in the fish gut. Further, this study highlighted where further research is a prerequisite to increase our basic understanding and search for novel bacteriocins to elucidate the proteins/peptides having antimicrobial properties for disease control in aquaculture as an alternative to antibiotics. [ABSTRACT FROM AUTHOR]

The present study investigates the anticancer and multidrug resistance (MDR) reversal potential of hydro-alcoholicEclipta albaextract (EAE) through in vivo experiments. Diethylnitrosamine (DEN) and 2-acetylaminofluorene (AAF) were used for liver cancer induction in animal model, whereas for MDR induction, AAF was used. The level of antioxidant enzymes was studied in serum along with biochemical parameters. Cancer and MDR-induced liver cells have higher levels of reactive oxygen species (ROS) and, in turn, are responsible for the maintenance of the cancer phenotype. Treatment with EAE declines the ROS level and revealed the ROS scavenging properties. Alfa feto protein levels were found to increase significantly in cancer-induced animals confirming induction and progression of liver cancer, EAE treatment was found to bring back the altered levels within normal range indicating the therapeutic effect of plant extract over liver cancer. Zymogram showed the inhibition of MMPs and RT-PCR analysis revealed that the mRNA expression of nuclear factor-kB was markedly decreased upon EAE treatment. Further, our results showed that EAE could significantly inhibit mdr1 gene encode P-glycoprotein expression. Our data suggest that EAE is a novel anticancer and potent MDR reversal agent and may be a potential adjunctive agent for tumor chemotherapy. [ABSTRACT FROM AUTHOR]

Novel therapeutic approaches are needed to combat the urinary tract infection in women. During menstruation elevated protein concentration and increase in oxygen and carbon dioxide concentrations with decrease in vaginal Lactobacilli all together contribute to urinary tract infections. Lactobacillus species are a predominant member of the vaginal microflora and are critical in the prevention of a number of urogenital diseases. In order to increase antimicrobial potential of vaginal Lactobacilli, bacteriocin colicin E2 which has specific activity against uropathogenic Escherichia coli has been overexpressed in vaginal probiotic Lactobacillus brevis DT24. Recombinant Lactobacillus brevis DT24 expressing colicin E2 showed much higher inhibitory activity against uropathogenic Escherichia coli than wild type L. brevis DT24 in vitro. Efficacy of probiotic Lactobacillus brevis DT24 expressing colicin E2 protein is required for further in vivo evaluation. [ABSTRACT FROM AUTHOR]

Novel therapeutic approaches are needed to combat the urinary tract infection in women. During menstruation elevated protein concentration and increase in oxygen and carbon dioxide concentrations with decrease in vaginal Lactobacilli all together contribute to urinary tract infections. Lactobacillus species are a predominant member of the vaginal microflora and are critical in the prevention of a number of urogenital diseases. In order to increase antimicrobial potential of vaginal Lactobacilli, bacteriocin colicin E2 which has specific activity against uropathogenic Escherichia coli has been overexpressed in vaginal probiotic Lactobacillus brevis DT24. Recombinant Lactobacillus brevis DT24 expressing colicin E2 showed much higher inhibitory activity against uropathogenic Escherichia coli than wild type L. brevis DT24 in vitro. Efficacy of probiotic Lactobacillus brevis DT24 expressing colicin E2 protein is required for further in vivo evaluation. [ABSTRACT FROM AUTHOR]

Novel therapeutic approaches are needed to combat the urinary tract infection in women. During menstruation elevated protein concentration and increase in oxygen and carbon dioxide concentrations with decrease in vaginal Lactobacilli all together contribute to urinary tract infections. Lactobacillus species are a predominant member of the vaginal microflora and are critical in the prevention of a number of urogenital diseases. In order to increase antimicrobial potential of vaginal Lactobacilli, bacteriocin colicin E2 which has specific activity against uropathogenic Escherichia coli has been overexpressed in vaginal probiotic Lactobacillus brevis DT24. Recombinant Lactobacillus brevis DT24 expressing colicin E2 showed much higher inhibitory activity against uropathogenic Escherichia coli than wild type L. brevis DT24 in vitro. Efficacy of probiotic Lactobacillus brevis DT24 expressing colicin E2 protein is required for further in vivo evaluation. [ABSTRACT FROM AUTHOR]

ABSTRACT The objective of the present study was to characterize lactobacilli isolates from the feces of male Wistar rats. Various physiological features of the candidate probiotic isolates were preliminarily investigated, including tolerance to simulated gastric juice and bile salts, antimicrobial activity, antibiotic susceptibility and in vitro aggregation. Based on their morphological and biochemical characteristics, four potential probiotic isolates (CS2, CS3, CS4, and CS7) were screened. The isolates showed good tolerance to stimulated gastric juice and bile salts. CS4 and CS7 exhibited strong antibacterial activities against the pathogens tested as assessed in neutral pH culture supernatants. All lactobacilli isolates were susceptible to all the tested antibiotics, except vancomycin. Moreover, the isolate CS4 and CS7 were found to possess stronger cell surface traits such as hydrophobicity, auto-aggregation and co-aggregation capacity. In addition, CS4 and CS7 had greater β-galactosidase activities than the others. Biochemical tests and 16S rRNA gene sequencing confirmed that CS2, CS3, CS4 and CS7 are Lactobacillus intestinalis PJ2, L. sakei PJ3, L. helveticus PJ4, and L. plantarum PJ7, respectively. Based on the obtained results, L. helveticus PJ4 and L. plantarum PJ7 are ideal in vitro probiotic candidates and require further in vivo evaluation. [ABSTRACT FROM AUTHOR]

It has been shown that the Western diet (WD) induces systemic inflammation and cognitive decline. Moreover, probiotic supplementation and antibiotic treatment reduce diet-induced hepatic inflammation. The current study examines whether shaping the gut microbes by Bifidobacterium infantis (B. infantis) supplementation and antibiotic treatment reduce diet-induced brain inflammation and improve neuroplasticity. Furthermore, the significance of bile acid (BA) signaling in regulating brain inflammation was studied. Mice were fed a control diet (CD) or WD for seven months. B. infantis was supplemented to WD-fed mice to study brain inflammation, lipid, metabolomes, and neuroplasticity measured by long-term potentiation (LTP). Broad-spectrum coverage antibiotics and cholestyramine treatments were performed to study the impact of WD-associated gut microbes and BA in brain inflammation. Probiotic B. infantis supplementation inhibited diet-induced brain inflammation by reducing IL6, TNFα, and CD11b levels. B. infantis improved LTP and increased brain PSD95 and BDNF levels, which were reduced due to WD intake. Additionally, B. infantis reduced cecal cholesterol, brain ceramide and enhanced saturated fatty acids. Moreover, antibiotic treatment, as well as cholestyramine, diminished WD-induced brain inflammatory signaling. Our findings support the theory that intestinal microbiota remodeling by B. infantis reduces brain inflammation, activates BA receptor signaling, and improves neuroplasticity. [ABSTRACT FROM AUTHOR]

We studied whether probiotics were beneficial for hormonal change-associated dysbiosis, which may influence the enteric nervous system and GI function during early pregnancy. The study was 16 days consisting of two cycles of six daily probiotics mainly Lactobacillus and 2 days without probiotics. Daily surveys were conducted to monitor GI function and life quality. A subset of the participants who contributed fecal specimens was used for microbiota metagenomic sequencing, metabolomics, and quantification of bacterial genes to understand potential underlying mechanisms. Statistical analyses were done by generalized linear mixed-effects models. Thirty-two obstetric patients and 535 daily observations were included. The data revealed that probiotic supplementation significantly reduced the severity of nausea, vomiting, constipation, and improved life quality. Moreover, a low copy number of fecal bsh (bile salt hydrolase), which generates free bile acids, was associated with high vomiting scores and probiotic intake increased fecal bsh. In exploratory analysis without adjusting for multiplicity, a low fecal α-tocopherol, as well as a high abundance of Akkemansia muciniphila, was associated with high vomiting scores and times, respectively. The potential implications of these biomarkers in pregnancy and GI function are discussed. Probiotics likely produce free bile acids to facilitate intestinal mobility and metabolism. [ABSTRACT FROM AUTHOR]

Long-term consumption of a diet with excessive fat and sucrose (Western diet, WD) leads to an elevated risk of obesity and metabolic syndrome in both males and females. However, there are sexual dimorphisms in metabolism which are apparent when considering the prevalence of complications of metabolic syndrome, such as non-alcoholic fatty liver disease. This study aimed to elucidate the impact of a WD on the metabolome and the gut microbiota of male and female mice at 5, 10, and 15 months to capture the dynamic and comprehensive changes brought about by diet at different stages of life. Here we show that there are important considerations of age and sex that should be considered when assessing the impact of diet on the gut microbiome and health. [ABSTRACT FROM AUTHOR]