Current and potential status of probiotics in inflammatory bowel diseases
The gut microbiota may play an important role in the aetiology of inflammatory bowel disease (IBD), such that reduced diversity and imbalance between commensal and pathogenic microorganisms leads to reduced function of the intestinal defence barrier and subsequent inflammation resulting from overstimulation of the intestinal immune system. Probiotic bacteria may shift the dysbiotic gut microbiota towards homeostasis, thus mitigating or repairing damage to the intestinal barrier, leading to symptom reduction and disease remission. However, clinical trials of probiotics in IBD have yielded disappointing results. The current article aims to address the issues and challenges facing the development of probiotics for clinical use in IBD.
PREVALENCE OF INFLAMMATORY BOWEL DISEASE (IBD)
Inflammatory Bowel Disease (IBD) manifests as chronic intestinal inflammation, characterised by periods of remission and relapse (1). The two main forms, Ulcerative Colitis (UC) and Crohn’s disease (CD) are differentiated by distinct histological and regional presentation (2). Extra-intestinal manifestations are also common; affecting joints, eyes and skin (3). Estimated prevalence of IBD in Europe may appear low at approximately 0.3% of general population (4), and worldwide incidence and prevalence continue to increase (5). The associated, often lifelong, morbidity has a significant social and economic impact on both individual and society. Prevalence is highest in industrialised nations, though incidence is increasing in Asia and Eastern Europe; perhaps linked to Westernisation of diet. Further, there appears to be a geographical split within Europe, indicating increased incidence within the North and West compared to the South and East (4).
GUT MICROBIOTA IN THE AETIOLOGY OF IBD
The human gut may host up to 100 trillion bacteria (6). The gut microbiota is normally transferre ...