Current Opinion in Endocrinology, Diabetes & Obesity:
GASTROINTESTINAL HORMONES: Edited by H. Christian Weber
Weber, H. Christian
Boston University School of Medicine, Section of Gastroenterology, Boston, Massachusetts, USA
Correspondence to H. Christian Weber, MD, Boston University School of Medicine, Section of Gastroenterology, 650 Albany Street, EBRC Room 508, Boston, MA 02118, USA. Tel: +1 617 638 8330; fax: +1 617 638 7785; e-mail: firstname.lastname@example.org
Gastrointestinal peptides interact with their target cells through binding to specific cell surface receptors or ion channels thereby exerting biological effects that regulate a broad range of digestive functions, including hormone release, acid and enzyme secretion, gut motility, satiety and appetite behaviour and energy homeostasis [1,2]. These peptides are synthesized in and secreted from enteroendocrine cells found scattered throughout the gastrointestinal tract. They respond to a variety of stimuli, including various constituents of the luminal gastrointestinal tract, and communicate to their target cells via paracrine, endocrine, neurocrine and autocrine routes [2,3].
In this issue, we provide an important clinical update on the possible link of the use of proton pump inhibitors (PPI) with various reported long-term side-effects. This is relevant in daily medical practice because hypochlorhydria due to ineffective or pharmacologically inhibited acid secretion occurs frequently. Owing to widespread use and frequent overutilization of PPI therapy, the main clinical concerns refer to a possible association with an increased risk of impaired bone health and the potential acquisition of certain enteric infections albeit causal relationships still remain elusive [4–12].
The biological heterogeneity of the scattered enteroendocrine cell system along the tubular intestinal tract is also reflected in the varied biology of malignancies derived from this system, the gastrointestinal neuroendocrine tumors (GI-NET) . This update on recent investigation of their genetic abnormalities and molecular pathology discusses putative new targets for specific pharmacological treatment options and novel blood-based diagnostic testing . These advances might be critical for the development of biologically more relevant criteria categorizing patients with NETs for randomized clinical trials. In previous clinical trials patients with NETs of considerable biological heterogeneity were combined and results may therefore not truly reflect outcomes for specific, biologically more homogenous GI-NETs.
Another new line of research has naturally engulfed the field of gastroenterology, namely, the rapidly expanding gathering of novel insights regarding the human gut microbiome. Gastroenterologists are confronted with patients every day in clinical practice wherein some aspects of this emerging field may be involved. Undoubtedly, the human gut microbiome has an important role in human health and disease likely affecting a large number of gastrointestinal conditions including inflammatory bowel disease, obesity, fatty liver, cancer and functional bowel disorders. At present, cause and effect of dysbiosis, the underlying mechanisms in the pathophysiology of disease and possible therapeutic interventions such as dietary modifications still remain to be elucidated [15–20]. Owing to the importance of this line of work and the anticipated large impact in future clinical practice of gastroenterology, this issue discusses specifically recent updates regarding the role of the gut microbiome in inflammatory bowel disease and irritable bowel syndrome.
Conflicts of interest
There are no conflicts of interest.
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