Interest toward the human microbiome, particularly gut microbiome has flourished in recent decades owing to the rapidly advancing sequence-based screening and humanized gnotobiotic model in interrogating the dynamic operations of commensal microbiota. Although this field is still at a very preliminary stage, whereby the functional properties of the complex gut microbiome remain less understood, several promising findings have been documented and exhibit great potential toward revolutionizing disease etiology and medical treatments. In this review, the interactions between gut microbiota and the host have been focused on, to provide an overview of the role of gut microbiota and their unique metabolites in conferring host protection against invading pathogen, regulation of diverse host physiological functions including metabolism, development and homeostasis of immunity and the nervous system. We elaborate on how gut microbial imbalance (dysbiosis) may lead to dysfunction of host machineries, thereby contributing to pathogenesis and/or progression toward a broad spectrum of diseases. Some of the most notable diseases namely Clostridium difficile infection (infectious disease), inflammatory bowel disease (intestinal immune-mediated disease), celiac disease (multisystemic autoimmune disorder), obesity (metabolic disease), colorectal cancer, and autism spectrum disorder (neuropsychiatric disorder) have been discussed and delineated along with recent findings. Novel therapies derived from microbiome studies such as fecal microbiota transplantation, probiotic and prebiotics to target associated diseases have been reviewed to introduce the idea of how certain disease symptoms can be ameliorated through dysbiosis correction, thus revealing a new scientific approach toward disease treatment. Toward the end of this review, several research gaps and limitations have been described along with suggested future studies to overcome the current research lacunae. Despite the ongoing debate on whether gut microbiome plays a role in the above-mentioned diseases, we have in this review, gathered evidence showing a potentially far more complex link beyond the unidirectional cause-and-effect relationship between them.
Anti-tumor necrosis factor (anti-TNF) is highly effective in inflammatory bowel disease (IBD); however, it is associated with an increased risk of infections, particularly in older adults. We reviewed 349 patients with IBD, who were observed over a 12-month period, 74 of whom had received anti-TNF therapy (71 patients were aged <60 years and 3 were aged ≥60 years). All the 3 older patients developed serious infectious complications after receiving anti-TNFs, although all of them were also on concomitant immunosuppressive therapy. One patient developed disseminated tuberculosis, another patient developed cholera diarrhea followed by nosocomial pneumonia, while the third patient developed multiple opportunistic infections (Pneumocystis pneumonia, cryptococcal septicemia and meningitis, Klebsiella septicemia). All 3 patients died within 1 year from the onset of the infection(s). We recommend that anti-TNF, especially when combined with other immunosuppressive therapy, should be used with extreme caution in older adult patients with IBD.
BACKGROUND: Little is known about autoimmune liver disease (AILD) in Asian children. We studied the clinical features and predictors of outcome in childhood AILD in an Asian population.
METHODS: Retrospective review of AILD [autoimmune hepatitis type 1 and 2 (AIH1, AIH2), primary sclerosing cholangitis (PSC) and autoimmune sclerosing cholangitis (ASC)] seen at two pediatric liver units in Malaysia.
RESULTS: At presentation, 17 (56%) of the 32 children [19 females, 59%; median (range) age 7.7 (1.8-15.5) years] with AILD (AIH1 = 18, AIH2 = 5, PSC = 0, ASC = 9) had liver cirrhosis. At final review [median (range) duration of follow-up 4.8 (0.4-12) years], 24 patients (75%) survived with a native liver. Twenty-one (66%) were in remission; 19 (AIH1 = 11; AIH2 = 4, ASC = 4) were on prednisolone and/or azathioprine, one on cyclosporine and another on mycophenolate mofetil. Three (AIH1 = 3) were in partial remission. Of the two who underwent liver transplantation (LT; 6.5%; both ASC), one died of primary graft failure after LT. Six patients (19%) died without LT (acute liver failure, n = 1; end-stage liver disease, n = 5). The overall survival rate (native liver and survival post-LT) was 78%. A delay in seeking treatment adversely affected the final outcome [survival with native liver vs. LT or death (duration between onset of disease and treatment; median ± standard error) = 2.5 ± 2.9 months vs. 24.0 ± 13.3 months; p = 0.012].
CONCLUSIONS: Although remission was achieved in the majority of patients with prednisolone and/or azathioprine therapy, delay in seeking diagnosis and treatment adversely affects the outcome of childhood AILD in Malaysia.
Inflammatory bowel diseases (IBD) encompass at least two forms of intestinal inflammation: Crohn's disease and ulcerative colitis (UC). Both conditions are chronic and inflammatory disorders in the gastrointestinal tract, with an increasing prevalence being associated with the industrialization of nations and in developing countries. Patients with these disorders are 10 to 20 times more likely to develop cancer of the colon. The aim of this study was to characterize the effects of a naturally occurring polyphenol, gallic acid (GA), in an experimental murine model of UC. A significant blunting of weight loss and clinical symptoms was observed in dextran sodium sulfate (DSS)-exposed, GA-treated mice compared with control mice. This effect was associated with a remarkable amelioration of the disruption of the colonic architecture, a significant reduction in colonic myeloperoxidase (MPO) activity, and a decrease in the expression of inflammatory mediators, such as inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and pro-inflammatory cytokines. In addition, GA reduced the activation and nuclear accumulation of p-STAT3(Y705), preventing the degradation of the inhibitory protein IκB and inhibiting of the nuclear translocation of p65-NF-κB in colonic mucosa. These findings suggest that GA exerts potentially clinically useful anti-inflammatory effects mediated through the suppression of p65-NF-κB and IL-6/p-STAT3(Y705) activation.