Non-alcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver disease and is highly correlated with metabolic disease. NAFLD results from environmental exposures acting on a susceptible polygenic background. This study performed the largest multiethnic investigation of exonic variation associated with NAFLD and correlated metabolic traits and diseases. An exome array meta-analysis was carried out among eight multiethnic population-based cohorts (n = 16 492) with computed tomography (CT) measured hepatic steatosis. A fixed effects meta-analysis identified five exome-wide significant loci (P < 5.30x10−7); including a novel signal near TOMM40/APOE. Joint analysis of TOMM40/APOE variants revealed the TOMM40 signal was attributed to APOE rs429358-T; APOE rs7412 was not associated with liver attenuation. Moreover, rs429358-T was associated with higher serum alanine aminotransferase, liver steatosis, cirrhosis, triglycerides and obesity; as well as, lower cholesterol and decreased risk of myocardial infarction (MI) and Alzheimer’s disease (ad) in phenome-wide association analyses in the Michigan Genomics Initiative, United Kingdom Biobank and/or public datasets. These results implicate APOE in imaging-based identification of NAFLD. This association may or may not translate to non-alcoholic steatohepatitis (NASH); however, these results indicate a significant association with advanced liver disease and hepatic cirrhosis. These findings highlight allelic heterogeneity at the APOE locus and demonstrate an inverse link between NAFLD and ad at the exome level in the largest analysis to date.

Context Glycogen storage diseases are rare. Increased glycogen in the liver results in increased attenuation. Objective Investigate the association and function of a noncoding region associated with liver attenuation but not histologic nonalcoholic fatty liver disease. Design Genetics of Obesity-associated Liver Disease Consortium Setting Population-based Main Outcome: Computed tomography measured liver attenuation. Results Carriers of rs4841132-A (frequency 2-19%) do not show increased hepatic steatosis; they have increased liver attenuation indicative of increased glycogen deposition. rs4841132 falls in a noncoding RNA LOC157273 ~190kb upstream of PPP1R3B. We demonstrate that rs4841132-A increases PPP1R3B through a cis genetic effect. Using CRISPR/Cas9 we engineered a 105bp deletion including rs4841132-A in human hepatocarcinoma cells which increases PPP1R3B, decreases LOC157273 and increases glycogen perfectly mirroring the human disease. Overexpression of PPP1R3B or knockdown of LOC157273 increased glycogen but did not result in decreased LOC157273 or increased PPP1R3B, respectively, suggesting that the effects may not all occur via affecting RNA levels. Based on EHR data, rs4841132-A associates with all components of the metabolic syndrome (MetS). However, rs4841132-A associated with decreased low-density lipoprotein (LDL) cholesterol and risk for myocardial infarction (MI). A metabolic signature for rs4841132-A includes increased glycine, lactate, triglycerides and decreased acetoacetate and beta-hydroxybutyrate. Conclusions These results show that rs4841132-A promotes a hepatic glycogen storage disease by increasing PPP1R3B and decreasing LOC157273. rs4841132-A promotes glycogen accumulation and development of MetS but lowers LDL cholesterol and risk for MI. These results suggest that elevated hepatic glycogen is one cause of MetS that does not invariably promote MI.

Iatrogenic injury to the oesophagus is a serious complication which is increasingly seen in clinical practice secondary to expansion and greater acceptability of surgical and endoscopic oesophageal procedures. Morbidity and mortality following such injury is high. This is mostly due to an inflammatory response to gastric contents in the mediastinum, and the negative intrathoracic pressures that may further draw out oesophageal contents into the mediastinum leading to mediastinitis. Subsequently, pulmonary complications such as pneumonia or abscess may ensue leading to rapid clinical deterioration. Optimized and timely cross-sectional imaging evaluation is necessary for early and aggressive management of these complications. The goal of this review is to make the radiologist aware of the importance of early and accurate identification of postoperative oesophageal injury using optimized CT imaging protocols and use of oral contrast. Specifically, it is critical to differentiate benign post-operative findings, such as herniated viscus or redundant anastomosis, from clinically significant postoperative complications as this helps guide appropriate management. Advantages and drawbacks of other diagnostic methods, such as contrast oesophagogram, are also discussed.

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Background: Transfemales are biological males at birth, but identify as female by gender. Gender-Affirming Hormone Therapy ( GAHT ) is used to alter hormone levels to match gender identity. GAHT in transfemales involves administration of estradiol ( E2 ) with an androgen antagonist ( AA ) or orchiectomy. Sex is an independent predictor of cardiovascular ( CV ) risk, but the role of sex hormones on CV risk in transfemales is unknown. Thus, this study tested the hypothesis that GAHT in male rats increases CV risk. Methods: Male Sprague Dawley ( SD ) rats were randomly assigned at 14 weeks of age to three groups that underwent either mean arterial pressure ( MAP , N=3-5/group) or metabolic (N=8/group) monitoring. Control ( C ): empty silastic capsule. E2+AA: silastic capsule with 17-beta E2 benzoate (5 mg/21 days) plus AA, spironolactone (10 mg/kg/day, incorporated in diet). E2+CTX: silastic capsule with E2 plus castration ( CTX ). Silastic capsules (+/- E2) were replaced every 21 days starting at 14 weeks. AA, started at 14 weeks of age, was continued in E2+AA but discontinued after CTX at 16 weeks of age in E2+CTX. Results: (Table 1) : The pressor response to angiotensin II ( ANG II ) was similar in C and E2+CTX but was blunted in E2+AA despite similar baseline MAP, increase in E2 and decrease in testosterone. Cholesterol was only increased in E2+AA. Conclusion: These results suggest that feminizing therapy in male rats is associated with similar changes in sex steroids but the pressor response to ANG II and lipid profile differ based on the method of androgen reduction. The use of a transfemale rodent model will allow study of the pathophysiology of increased CV risk associated with GAHT across the lifespan.

Migration of monocytes‐macrophages play an important role in phagocytosis of pathogens and cellular debris in a variety of pathophysiological conditions. While Epithelial Na+ Channels (ENaC) are required for normal migratory responses in glial, trophoblast, and vascular smooth muscle cells, their role in monocyte‐macrophage migration signaling is unknown. The Human Protein Atlas data base (http://www.proteinatlas.org/) shows ENaC message in peripheral blood mononuclear cells and tissue resident macrophages in human populations. We used an in vitro model to determine the importance of ENaC in chemotactic migration of monocytes‐macrophages using a standard Boyden chamber assay. Cells were suspended in 0.4% FBS ± amiloride (0.1‐10 µM) or benzamil (0.01‐1 µM) to inhibit ENaC channels, then migrated for 4 hr towards a 10% FBS gradient. In mouse RAW cells, migration responses were inhibited by amiloride (65±6 – 46±4% of control at 0.1 and 10 µM, p=0.0001) and benzamil (55±6 – 55±5% of control at 0.01 and 1.0 µM, p<0.0001). In human THP‐1 cells, migration responses were similarly inhibited by amiloride (73±5 ‐ 40±6% of control at 0.1 and 10 µM, p<0.0001) and benzamil (68±7 – 53±4% of control at 0.01 and 1.0 µM, p<0.0001). Since benzamil and amiloride are selective for ENaC at sub and low micromolar concentrations, respectively, our findings indicate ENaC signaling is required for migration of unstimulated monocyte‐macrophage cells. To determine if pro‐inflammatory cytokines, such as tumor necrosis factor alpha (TNFα) and interferon gamma (INFγ), regulate ENaC expression and function, we used TaqMan quantitative PCR, western blotting and chemotactic migration. Cells were exposed to a standard protocol to activate macrophages: INFγ for 48 hr plus TNFα (10 ng/mL each) during the last 24 hr. Expression of α and βENaC and GAPDH was calculated as fold change using the delta delta CT method (2‐∆∆CT). INFγ48hr + TNFα24hr increased α and βENaC message (9±2 and 5±1, n=4‐6, p=0.01). γENaC was undetectable. Despite increased message, whole cell αENaC protein expression was inhibited 50% by western blotting. The mechanism underlying message stimulation and protein inhibition remains to be determined. A similar effect on message upregulation and migration inhibition also occurred with 18 hr INFγ or TNFα alone (0‐10 ng/mL). Activation with INFγ/TNFα inhibited migration up to 70% and abolished the amiloride (1 µM) sensitive component. In unstimulated cells, amiloride (1 µM) coculture induced a rebound increase in migration following withdrawal, which was abolished by INFγ/TNFα treatment. This finding suggests cytokine induced ENaC loss mediates the migration inhibition. In summary, ENaC mediates monocyte migration, however, monocyte activation by INFγ/TNFα inhibits migration by inhibiting ENaC. Since pro‐inflammatory cytokines initiate monocyte differentiation and polarization to the phagocytic M1 phenotype, future studies will determine if ENaC is required for the phenotypic switch.

The diheme enzyme MauG catalyzes oxidative posttranslational modifications of a protein substrate, preMADH, that binds to the surface of MauG. The high-spin heme iron of MauG is located 40 Å from preMADH. The ferric heme is an equilibrium of five- and six-coordinate states. PreMADH binding increases the proportion of five-coordinate heme three-fold. On reaction of MauG with H2O2 both hemes become FeIV. In the absence of preMADH the hemes autoreduce to ferric in a multistep process involving multiple electron and proton transfers. Binding of preMADH in the absence of catalysis alters the mechanism of autoreduction of the ferryl heme. Thus, substrate binding alters the environment in the distal heme pocket of the high-spin heme over very long distance.