Liver-specific ceramide reduction alleviates steatosis and insulin resistance in alcohol-fed mice.

Alcohol's impairment of both hepatic lipid metabolism and insulin resistance (IR) are key drivers of alcoholic steatosis, the initial stage of alcoholic liver disease (ALD). Pharmacologic reduction of lipotoxic ceramide prevents alcoholic steatosis and glucose intolerance in mice, but potential off-target effects limit its strategic utility. Here, we employed a hepatic-specific acid ceramidase (ASAH) overexpression model to reduce hepatic ceramides in a Lieber-DeCarli model of experimental alcoholic steatosis. We examined effects of alcohol on hepatic lipid metabolism, body composition, energy homeostasis, and insulin sensitivity as measured by hyperinsulinemic-euglycemic clamp. Our results demonstrate that hepatic ceramide reduction ameliorates the effects of alcohol on hepatic lipid droplet (LD) accumulation by promoting VLDL secretion and lipophagy, the latter of which involves ceramide cross-talk between the lysosomal and LD compartments. We additionally demonstrate that hepatic ceramide reduction prevents alcohol's inhibition of hepatic insulin signaling. These effects on the liver are associated with a reduction in oxidative stress markers and are relevant to humans, as we observe peri- LD ASAH expression in human ALD. Together, our results suggest a potential role for hepatic ceramide inhibition in preventing ALD.

A novel role for ceramide synthase 6 in mouse and human alcoholic steatosis.

Perilipin 2 (PLIN2) is a lipid-droplet protein that is up-regulated in alcoholic steatosis and associated with hepatic accumulation of ceramides, bioactive lipids implicated in alcoholic liver disease pathogenesis. The specific role of ceramide synthetic enzymes in the regulation of PLIN2 and promotion of hepatocellular lipid accumulation is not well understood. We examined the effects of pharmacologic ceramide synthesis inhibition on hepatic PLIN2 expression, steatosis, and glucose and lipid homeostasis in mice with alcoholic steatosis and in ethanol-incubated human hepatoma VL17A cells. In cells, pharmacologic inhibition of ceramide synthase reduced lipid accumulation by reducing PLIN2 RNA stability. The subtype ceramide synthase (CerS)6 was specifically up-regulated in experimental alcoholic steatosis in vivo and in vitro and was up-regulated in zone 3 hepatocytes in human alcoholic steatosis. In vivo ceramide reduction by inhibition of de novo ceramide synthesis reduced PLIN2 and hepatic steatosis in alcohol-fed mice, but only de novo synthesis inhibition, not sphingomyelin hydrolysis, improved glucose tolerance and dyslipidemia. These findings implicate CerS6 as a novel regulator of PLIN2 and suggest that ceramide synthetic enzymes may promote the earliest stage of alcoholic liver disease, alcoholic steatosis.-Williams, B., Correnti, J., Oranu, A., Lin, A., Scott, V., Annoh, M., Beck, J., Furth, E., Mitchell, V., Senkal, C. E., Obeid, L., Carr, R. M. A novel role for ceramide synthase 6 in mouse and human alcoholic steatosis.

Intestinal Inflammation Does Not Predict Nonalcoholic Fatty Liver Disease Severity in Inflammatory Bowel Disease Patients.

BACKGROUND AND AIM: Nonalcoholic fatty liver disease (NAFLD) is a common cause of hepatic steatosis in patients with inflammatory bowel disease (IBD). Both metabolic syndrome (MetS) and intestinal inflammation are implicated in NAFLD pathogenesis. METHODS: We performed a retrospective cohort study of patients with IBD and NAFLD seen in our health system from January 1997 to December 2011 to examine associations between IBD severity and phenotype; MetS; and NAFLD fibrosis as estimated by the NAFLD Fibrosis Score (NFS). RESULTS: A total of 84 patients were included in our analysis (24 UC, 60 CD). 23% of patients had MetS. IBD patients with MetS were significantly older at the time of IBD diagnosis (44 vs. 33, p = 0.005) and NAFLD diagnosis (55 vs. 47, p = 0.018). IBD patients with MetS had higher ALT (54 vs. 38 U/L, p = 0.02) and AST (52 vs. 35 U/L, p = 0.004). Comparing MetS patients to non-MetS IBD patients, there was no significant difference between IBD medication use (i.e., steroids, anti-TNFs, and immunomodulators) or NAFLD medication use, other than statins. Both UC and CD patients with concomitant MetS had significantly higher NFS scores than non-MetS patients: UC (-0.4 vs. -2.5, p = 0.02) and CD (-0.8 vs. -2.3, p = 0.03). IBD disease severity, disease location, or IBD medication use was associated with NAFLD severity. CONCLUSIONS: To our knowledge, this is the first study to demonstrate that NAFLD severity in both UC and CD IBD patients is associated with the presence of MetS but not with the severity of IBD.

Prevalence and Impact of Gastrointestinal Manifestations in COVID-19 Patients: A Systematic Review.

Background and objective: The aim of this study is to systematically analyze and summarize the implications of COVID-19 on the digestive system by quantitatively evaluating the prevalence of gastrointestinal symptoms such as nausea, vomiting, abdominal pain, constipation, diarrhea, anorexia. reported in COVID-19 cases. We simultaneously investigated other variables to determine the association of such symptoms in COVID-19 patients which can potentially influence the disease prognosis and outcome. This systematic review presents an updated literature on the issue as it requires more scientific discussion in order to better inform the medical community and authorities so that appropriate measures can be taken to control the virus outbreak. Methods: MEDLINE database was searched to identify relevant articles. Data was analyzed and synthesized from the 16 eligible studies which exclusively reported GI symptoms in COVID-19 patients along with the disease prognosis. A meta-analysis of studies having adequate information regarding the prevalence of specific GI symptoms in association with other relevant independent variables was performed. Results: From the search strategy, we identified 16 articles which fit our eligibility criteria comprising of 10 cross-sectional studies, 2 cohort study, 1 RCT and 3 observational studies. From these pooled studies, 6 articles exclusively talked about COVID-19 patients in which GI symptoms were reported and adequately discussed. In a total of 3646 patients, GI symptoms were documented in (16.2%-10.1%) patients. The most prevalent GI symptom was diarrhea (47%) but the most common clinical manifestation reported was fever (77.4%). Among the adult patients, hypertension (11.6%) was the most frequently reported comorbidity. Presence of viral RNA in stool sample was noted in 16.7% patients with GI symptom. In patients who complained of having GI symptoms, an abnormal liver function was largely observed, with an elevated ALT level in (10.9%) and an elevated AST in (8.8%) of the patients. Evidence of vertical transmission (14.2%) was reported in one study which highlights the extent and mode of viral transmission. It was observed that a great majority of the patients in the 6 studies reporting specifically on patients with GI symptoms were on antiviral therapy (68.6%) as the standard disease management protocol but the eventual disease outcome as in this case died (8.4%), discharged (45.6%) was not linked to just one therapeutic factor but other indicators of disease severity such as positive chest CT findings (87.82%) have led to a poor disease prognosis which was noted in (28.9%) severe patients with GI symptoms compared to (71.1%) non-severe COVID-19 patients with GI symptom. Conclusion: Presence of GI symptoms in COVID-19 patients has shown to have a positive association with the poor disease prognosis likely as a result of direct viral toxicity. It is important for the physicians to recognize digestive symptoms as an important characteristic in COVID-19 patients. Hence, precise and targeted documentation of GI symptoms and viral stool sample investigations should be performed in order to understand the rapidly evolving disease symptomology.

Esophagitis Dissecans Superficialis: A Frequently Missed and Rarely Reported Diagnosis.

Esophagitis dissecans superficialis (EDS) is a rare esophageal disease with a wide spectrum of presentations from asymptomatic to debilitating symptoms. There is a strong association of EDS with autoimmune diseases, smoking, and medications, but it can also be idiopathic. Due to the sporadic occurrence of EDS, identification requires a high index of suspicion to avoid frequent misdiagnoses. Herein, we present a case of EDS associated with the long-standing use of oral diclofenac with a favorable outcome after therapy with a proton pump inhibitor (PPI).

Gastrointestinal Hemorrhage Due to Duodenal Varix: A Case Report.

We report a case of a 72-year-old female with a past medical condition of non-alcoholic steatohepatitis who presented in the emergency department with altered mentation. An Esophagogastroduodenoscopy was performed which showed a normal esophagus and stomach, but revealed grade III varices which were appreciable in the second portion of the duodenum. Her colonoscopy report revealed multiple small and large mouthed diverticula in the sigmoid colon along with hematin throughout the colon, yet no evidence of active bleeding, mass or inflammation. We discuss the patient's rarity of the clinical entity, clinical development, and elements used for diagnosis along with the treatment modalities involved.

Caution about overinterpretation of symptom indexes in reflux monitoring for refractory gastroesophageal reflux disease.

BACKGROUND & AIMS: Symptom index (SI) and symptom association probability (SAP) are indexes used to analyze data collected from ambulatory pH and/or impedance monitoring and quantify the association between symptoms and reflux events. However, their characteristics are not well defined. We measured factors that affect SI and SAP values to determine their utility in assessing patients with refractory gastroesophageal reflux disease (GERD). METHODS: We conducted a cross-sectional study of 254 patients with poor responses to proton pump inhibitor (PPI) therapy. Participants underwent esophagogastroduodenoscopy and wireless pH (n = 127) or impedance/pH monitoring when they were not receiving PPI therapy (n = 41) or impedance/pH monitoring while they received twice-daily PPI therapy (n = 86). SI and SAP values were calculated individually; ranges of values for each cell in the 2 × 2 contingency table were determined. Monte Carlo simulation was conducted to determine how varying reflux and symptom rates within the contingency table impacted the expected value and variability in SI and SAP. RESULTS: At best, only 33% of patients who were refractory to PPI therapy had positive SI or SAP scores for acid or nonacid reflux events. Abnormal SAP (>95%) and SI (>50%) scores required high rates of reflux. At reflux rates less than 10%, observed in 70% of the studied population, SI and SAP values were largely determined by chance occurrences, rather than the relationship between symptoms and reflux. The values for each index varied significantly day-to-day. CONCLUSIONS: SI or SAP indexes can be overinterpreted, unless patients with gastroesophageal reflux disease who are refractory to PPI therapy have high rates of reflux.

Unusual case of dysphagia in a male.

Plummer Vinson Syndrome, a triad of dysphagia, esophageal web, and iron-deficiency anemia, is a rarely reported diagnosis in current literature. The exact etiology of the syndrome remains controversial, but it has been linked to complicated nutritional deficiencies, autoimmune disorders, and hereditary factors, and has a remarkably high female to male ratio. This paper describes an atypical case presentation in a 53-year-old male with a remote history of peptic ulcer disease surgery.

Rapid Lipid Droplet Isolation Protocol Using a Well-established Organelle Isolation Kit.

Lipid droplets (LDs) are bioactive organelles found within the cytosol of the most eukaryotic and some prokaryotic cells. LDs are composed of neutral lipids encased by a monolayer of phospholipids and proteins. Hepatic LD lipids, such as ceramides, and proteins are implicated in several diseases that cause hepatic steatosis. Although previous methods have been established for LD isolation, they require a time-consuming preparation of reagents and are not designed for the isolation of multiple subcellular compartments. We sought to establish a new protocol to enable the isolation of LDs, endoplasmic reticulum (ER), and lysosomes from a single mouse liver. Further, all reagents used in the protocol presented here are commercially available and require minimal reagent preparation without sacrificing LD purity. Here we present data comparing this new protocol to a standard sucrose gradient protocol, demonstrating comparable purity, morphology, and yield. Additionally, we can isolate ER and lysosomes using the same sample, providing detailed insight into the formation and intracellular flux of lipids and their associated proteins.

Ethanol and C2 ceramide activate fatty acid oxidation in human hepatoma cells.

Obesogenic lipids and the sphingolipid ceramide have been implicated as potential cofactors in alcoholic liver disease (ALD) patients. However, the mechanisms by which these lipids modulate lipid trafficking in ethanol-treated human liver cells to promote steatosis, an early stage of ALD, are poorly understood. We measured fatty acid (FA) uptake, triglyceride export, FA synthesis and FA oxidation in human hepatoma (VL-17A) cells in response to ethanol and the exogenous lipids oleate, palmitate and C2 ceramide. We found that in combination with ethanol, both oleate and palmitate promote lipid droplet accumulation while C2 ceramide inhibits lipid droplet accumulation by enhancing FA oxidation. Further, using both a pharmacologic and siRNA approach to reduce peroxisome proliferator-activated receptors α (PPARα) gene expression, we demonstrate that C2 ceramide abrogates ethanol-mediated suppression of FA oxidation through an indirect PPARα mechanism. Together, these data suggest that lipids interact differentially with ethanol to modulate hepatocellular lipid droplet accumulation and may provide novel targets for preventing the earliest stage of alcoholic liver disease, alcoholic steatosis.

Nonalcoholic Fatty Liver Disease: Pathophysiology and Management.

Nonalcoholic fatty liver disease (NAFLD) is an important cause of morbidity and mortality worldwide and is rapidly becoming the leading cause of end-stage liver disease and liver transplant. With a prevalence of 30% in the United States, it has reached epidemic proportions. The clinical syndrome of NAFLD spans from bland steatosis to steatohepatitis, which can progress to fibrosis and cirrhosis. The pathogenesis includes the roles of hormones, nutritional and intestinal dysbiosis, insulin resistance, lipotoxicity, hepatic inflammation, and genes. Noninvasive testing and liver biopsy indications are reviewed. Approved and investigational therapies for NAFLD and nonalcoholic steatohepatitis are outlined in this article.

UHRF1 phosphorylation by cyclin A2/cyclin-dependent kinase 2 is required for zebrafish embryogenesis.

Ubiquitin-like, containing PHD and RING finger domains 1 (uhrf1) is regulated at the transcriptional level during the cell cycle and in developing zebrafish embryos. We identify phosphorylation as a novel means of regulating UHRF1 and demonstrate that Uhrf1 phosphorylation is required for gastrulation in zebrafish. Human UHRF1 contains a conserved cyclin-dependent kinase 2 (CDK2) phosphorylation site at Ser-661 that is phosphorylated in vitro by CDK2 partnered with cyclin A2 (CCNA2), but not cyclin E. An antibody specific for phospho-Ser-661 recognizes UHRF1 in both mammalian cancer cells and in nontransformed zebrafish cells, but not in zebrafish bearing a mutation in ccna2. Depleting Uhrf1 from zebrafish embryos by morpholino injection causes arrest before gastrulation and early embryonic death. This phenotype is rescued by wild-type UHRF1, but not by UHRF1 in which the phospho-acceptor site is mutated, demonstrating that UHRF1 phosphorylation is essential for embryogenesis. UHRF1 was detected in the nucleus and cytoplasm, whereas nonphosphorylatable UHRF1 is unable to localize to the cytoplasm, suggesting the importance of localization in UHRF1 function. Together, these data point to an essential role for UHRF1 phosphorylation by CDK/CCNA2 during early vertebrate development.

Noncardiac chest pain: gastroesophageal reflux disease.

Noncardiac chest pain (NCCP) is not only a difficult disorder to define but is also complex in characterization and treatment. Patients with NCCP are a challenge to primary care and subspecialty services such as cardiology and gastroenterology. NCCP is often a heterogeneous disorder with many potential causes including gastroenterologic diagnoses. This article presents the current evidence for gastroesophageal reflux disease as a cause of NCCP and highlights the best currently available tests for this group of patients.

Eosinophilic pleural effusion: a rare manifestation of hypereosinophilic syndrome.

Several causes of eosinophilic pleural effusions have been described with malignancy being the commonest cause. Hypereosinophilic syndrome (HES) is a rare disease and very few cases have been reported of HES presenting as eosinophilic pleural effusion (EPE). We report a case of a 26-year-old male who presented with shortness of breath. He had bilateral pleural effusions, generalized lymphadenopathy, splenomegaly, and leukocytosis with marked peripheral blood eosinophilia. The pleural fluid was exudative, with 25%-30% eosinophilis, and absence of neoplastic cells. Hypereosinophilic syndrome was diagnosed after other causes of eosinophilia were excluded. He continued to be dyspneic with persistent accumulation of eosinophilic pleural fluid, even after his peripheral eosinophil count had normalized in response to treatment. This patient represents a very unusual presentation of HES with dyspnea and pleural effusions and demonstrates that treatment based on response of peripheral eosinophil counts, as is currently recommended, may not always be clinically adequate.