Treatment and Management of Gastrointestinal Disorders.

This article reviews the evaluation and management of several gastrointestinal disorders that are commonly encountered by gastroenterologists and primary care physicians. With a focus on newer therapies, we discuss the management of chronic constipation, irritable bowel syndrome, Clostridioides difficile infection, gastroparesis, steatotic liver disease, and diverticulitis.

Cirrhotic cardiomyopathy: Appraisal of the original and revised criteria in predicting posttransplant cardiac outcomes.

Cardiovascular disease (CVD) significantly contributes to morbidity and mortality after liver transplantation (LT). Cirrhotic cardiomyopathy (CCM) is a risk factor for CVD after transplant. CCM criteria were originally introduced in 2005 with a revision proposed in 2020 reflecting echocardiographic technology advancements. This study assesses the two criteria sets in predicting major adverse cardiac events (MACE) after transplant. This single-center retrospective study reviewed adult LT recipients between January 1, 2009, and December 31, 2018. Patients with insufficient pre-LT echocardiographic data, prior ischemic heart disease, portopulmonary hypertension, or longitudinal care elsewhere were excluded. The primary composite outcome was MACE (arrhythmia, heart failure, cardiac arrest, and/or cardiac death) after transplant. Of 1165 patients, 210 met the eligibility criteria. CCM was present in 162 patients (77%) per the original criteria and 64 patients (30%) per the revised criteria. There were 44 MACE and 31 deaths in the study period. Of the deaths, 38.7% occurred secondary to CVD. CCM defined by the original criteria was not associated with MACE after LT (p = 0.21), but the revised definition was significantly associated with MACE (hazard ratio [HR], 1.93; 95% confidence interval, 1.05-3.56; p = 0.04) on multivariable analysis. Echocardiographic variable analysis demonstrated low septal e' as the most predictive variable for MACE after LT (HR, 3.45; p < 0.001). CCM, only when defined by the revised criteria, was associated with increased risk for MACE after LT, validating the recently revised CCM definition. Abnormal septal e', reflecting impaired relaxation, appears to be the most predictive echocardiographic criterion for MACE after LT.

Myeloid P2Y2 receptor promotes acute inflammation but is dispensable for chronic high-fat diet-induced metabolic dysfunction.

The purinergic receptor P2Y2 binds ATP to control chemotaxis of myeloid cells, and global P2Y2 receptor knockout mice are protected in models of acute inflammation. Chronic inflammation mediated by macrophages and other immune cells in adipose tissue contributes to the development of insulin resistance. Here, we investigate whether mice lacking P2Y2 receptors on myeloid cells are protected against acute and chronic inflammation. Wild-type mice were transplanted with either wild-type or P2Y2 receptor null bone marrow and treated with a sublethal dose of endotoxin as a model of acute inflammation, or fed a high-fat diet to induce obesity and insulin resistance as a model of chronic inflammation. P2Y2-/- chimeric mice were protected against acute inflammation. However, high-fat diet feeding induced comparable inflammation and insulin resistance in both WT and P2Y2-/- chimeric mice. Of note, confocal microscopy revealed significantly fewer crown-like structures, assemblies of macrophages around adipocytes, in P2Y2-/- chimeric mice compared to WT chimeric mice. We conclude that P2Y2 receptors on myeloid cells are important in mediating acute inflammation but are dispensable for the development of whole body insulin resistance in diet-induced obese mice.

Disabled homolog 2 controls macrophage phenotypic polarization and adipose tissue inflammation.

Acute and chronic tissue injury results in the generation of a myriad of environmental cues that macrophages respond to by changing their phenotype and function. This phenotypic regulation is critical for controlling tissue inflammation and resolution. Here, we have identified the adaptor protein disabled homolog 2 (DAB2) as a regulator of phenotypic switching in macrophages. Dab2 expression was upregulated in M2 macrophages and suppressed in M1 macrophages isolated from both mice and humans, and genetic deletion of Dab2 predisposed macrophages to adopt a proinflammatory M1 phenotype. In mice with myeloid cell-specific deletion of Dab2 (Dab2fl/fl Lysm-Cre), treatment with sublethal doses of LPS resulted in increased proinflammatory gene expression and macrophage activation. Moreover, chronic high-fat feeding exacerbated adipose tissue inflammation, M1 polarization of adipose tissue macrophages, and the development of insulin resistance in DAB2-deficient animals compared with controls. Mutational analyses revealed that DAB2 interacts with TNF receptor-associated factor 6 (TRAF6) and attenuates IκB kinase ß-dependent (IKKß-dependent) phosphorylation of Ser536 in the transactivation domain of NF-κB p65. Together, these findings reveal that DAB2 is critical for controlling inflammatory signaling during phenotypic polarization of macrophages and suggest that manipulation of DAB2 expression and function may hold therapeutic potential for the treatment of acute and chronic inflammatory disorders.