The Impact of Obesity on Inflammatory Bowel Disease

An overview on the cellular mechanisms of anthocyanins in maintaining intestinal integrity and function

Structural and functional changes of the intestinal barrier, as a consequence of a number of (epi)genetic and environmental causes, have a main role in penetrations of pathogens and toxic agents, and lead to the development of inflammation-related pathological conditions, not only at the level of the GI tract but also in other extra-digestive tissues and organs. Anthocyanins (ACNs), a subclass of polyphenols belonging to the flavonoid group, are well known for their health-promoting properties and are widely distributed in the human diet. There is large evidence about the correlation between the human intake of ACN-rich products and a reduction of intestinal inflammation and dysfunction. Our review describes the more recent advances in the knowledge of cellular and molecular mechanisms through which ACNs can modulate the main mechanisms involved in intestinal dysfunction and inflammation, in particular the inhibition of the NF-κB, JNK, MAPK, STAT3, and TLR4 proinflammatory pathways, the upregulation of the Nrf2 transcription factor and the expression of tight junction proteins and mucins.

Surgical treatment of inflammatory bowel disease: From the gastroenterologist's stand-point

Treatment of ulcerative colitis (UC) and Crohn's disease (CD) represents, in the majority of cases, a real challenge to the gastroenterologist's abilities and skills as well as a clinical test concerning his/her levels of medical knowledge and experience. During the last two decades, our pharmaceutical arsenal was significantly strengthened, especially after the introduction of the so-called biological agents, drugs which to a large extent not only improved the results of conservative treatment but also changed the natural history of the disease. However, colectomy is still necessary for some patients with severe UC although smaller compared to the past, precisely because of the improvements achieved in the available conservative treatment. Nevertheless, surgeries to treat colon dysplasia and cancer are increasing to some extent. At the same time, satisfactory improvements in surgical techniques, the pre-and post-operative care of patients, as well as the selection of the appropriate time for performing the surgery have been noticed. Regarding patients with CD, the improvement of conservative treatment did not significantly change the need for surgical treatment since two-thirds of patients need to undergo surgery at some point in the course of their disease. On the other hand, the outcome of the operation has improved through good preoperative care as well as the wide application of more conservative surgical techniques aimed at keeping as much of the bowel in situ as possible. This article discusses the indications for surgical management of UC patients from the gastroenterologist's point of view, the results of the emerging new techniques such as transanal surgery and robotics, as well as alternative operations to the classic ileo-anal-pouch anastomosis. The author also discusses the basic principles of surgical management of patients with CD based on the results of the relevant literature. The self-evident is emphasized, that is, to achieve an excellent therapeutic result in patients with severe inflammatory bowel disease in today's era; the close cooperation of gastroenterologists with surgeons, pathologists, imaging, and nutritionists is of paramount importance.

Cellular and Molecular Determinants of Biologic Drugs Resistance and Therapeutic Failure in Inflammatory Bowel Disease

The advent of biologic drugs has revolutionized the treatment of Inflammatory Bowel Disease, increasing rates of response and mucosal healing in comparison to conventional therapies by allowing the treatment of corticosteroid-refractory cases and reducing corticosteroid-related side effects. However, biologic therapies (anti-TNFα inhibitors, anti-α4β7 integrin and anti-IL12/23) are still burdened by rates of response that hover around 40% (in biologic-naïve patients) or lower (for biologic-experienced patients). Moreover, knowledge of the mechanisms underlying drug resistance or loss of response is still scarce. Several cellular and molecular determinants are implied in therapeutic failure; genetic predispositions, in the form of single nucleotide polymorphisms in the sequence of cytokines or Human Leukocyte Antigen, or an altered expression of cytokines and other molecules involved in the inflammation cascade, play the most important role. Accessory mechanisms include gut microbiota dysregulation. In this narrative review of the current and most recent literature, we shed light on the mentioned determinants of therapeutic failure in order to pave the way for a more personalized approach that could help avoid unnecessary treatments and toxicities.

Extracellular Vesicles: Novel Potential Therapeutic Agents in Inflammatory Bowel Diseases

Patients affected by inflammatory bowel diseases (IBD) can nowadays benefit from a growing number of pharmacological options. However, in moderate-to-severe cases, the therapeutic response is still far from optimal, and treatment changes and optimizations are often required. Thus, researchers in this field are strongly engaged in studies aiming to identify new potential therapeutic targets. Extracellular vesicles (EVs) are tiny subcellular bodies with a phospholipid bilayer envelope containing bioactive molecules, which are released from different cells and are involved in intercellular communication. Recent pre-clinical data show their emerging role in the pathogenesis and treatment of IBD. In our review, we summarize current evidence about the function of EVs as active therapeutic agents in ulcerative colitis and Crohn's disease, analyzing the properties of EVs derived from different cellular sources and the mechanisms through which they may improve intestinal inflammation.