Neurological applications of belzutifan in von Hippel-Lindau disease.

Von Hippel-Lindau (VHL) disease is a tumor predisposition syndrome caused by mutations in the VHL gene that presents with visceral neoplasms and growths, including clear cell renal cell carcinoma, and central nervous system manifestations, such as hemangioblastomas of the brain and spine. The pathophysiology involves dysregulation of oxygen sensing caused by the inability to degrade HIFα, leading to the overactivation of hypoxic pathways. Hemangioblastomas are the most common tumors in patients with VHL and cause significant morbidity. Until recently, there were no systemic therapies available for patients that could effectively reduce the size of these lesions. Belzutifan, the first approved HIF-2α inhibitor, has demonstrated benefit in VHL-associated tumors, with a 30% response rate in hemangioblastomas and ~30%-50% reduction in their sizes over the course of treatment. Anemia is the most prominent adverse effect, affecting 76%-90% of participants and sometimes requiring dose reduction or transfusion. Other significant adverse events include hypoxia and fatigue. Overall, belzutifan is well tolerated; however, long-term data on dosing regimens, safety, and fertility are not yet available. Belzutifan holds promise for the treatment of neurological manifestations of VHL and its utility may influence the clinical management paradigms for this patient population.

Dopamine D1-like receptors in prelimbic, but not infralimbic, medial prefrontal cortex contribute to chronic stress-induced increases in cue-induced relapse to palatable food seeking during forced abstinence.

Chronic stress exposure causes increased vulnerability to future relapse-like behavior in male, but not female, rats with a history of palatable food self-administration. These effects are mediated by dopamine D1-like receptors, but the anatomical location of chronic stress' dopaminergic mechanism is not known. Thus, male rats were trained to respond for palatable food pellets in daily sessions. During subsequent forced abstinence from food self-administration, stress was manipulated (0 or 3 h restraint/day for 7 days). Rats also received bilateral microinjections of the D1-like receptor antagonist SCH-23390 (0.25 µg/0.5 µl/side) or vehicle (0.5 µl/side) delivered to either prelimbic or infralimbic medial prefrontal cortex prior to daily treatments. Relapse tests in the presence of food-associated cues were conducted 7 days after the last treatment. Stress caused an increase and a decrease in responding during relapse tests in rats that received prelimbic vehicle and SCH-23390 infusions, respectively, relative to unstressed rats. In rats receiving IL infusions, however, stress caused an increase in responding regardless of whether the infusion was vehicle or SCH-23390. These results establish a specific role for prelimbic D1-like receptors in chronic stress-potentiated relapse.

Association of PNPLA3 I148M with Liver Disease Biomarkers in Latinos.

INTRODUCTION: Liver disease accounts for approximately 2 million deaths per year worldwide. The majority of liver diseases are due to complications of cirrhosis, viral hepatitis, and hepatocellular carcinoma. Increased levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) may indicate liver disease. Moreover, there are additional noninvasive liver fibrosis indices that help to estimate liver damage, including AST-to-ALT ratio, AST-to-platelet ratio index (APRI), fibrosis-4 (FIB-4) score, and nonalcoholic fatty liver disease (NAFLD) fibrosis score. The aims of the present study were to (1) perform an association analysis of the patatin-like phospholipase domain containing 3 (PNPLA3) I148M (rs738409) variant with ALT, AST, and various liver fibrosis indices, and (2) determine whether there are gender-related differences in these associations. METHODS: We obtained demographic, anthropometric, and metabolic phenotypes from Latino adult participants (n = 503, 64% female, 36.4 ± 0.5 years) from the Arizona Insulin Resistance (AIR) registry. SNP genotyping of I148M was performed using the TaqMan allelic discrimination assay. We used linear regression for the association analyses of the genotypes with ALT, AST, and the various liver fibrosis indices. We included genotype, age, body mass index, and alcohol status in the linear regression model. RESULTS: The variant I148M was in Hardy-Weinberg equilibrium, with genotype distribution: non-risk CC 118, heterozygous CG 246, and risk GG 139. The G allele was significantly associated with increased ALT and AST levels (p = 7.8 × 10-7 and p = 9.7 × 10-6, respectively). Moreover, we showed that the G allele was significantly associated with higher APRI (p = 3.7 × 10-7) and FIB-4 score (p = 4.1 × 10-3). When we analyzed the data by gender, we observed similar significant trends for ALT, AST, and APRI (all, p < 0.01). In females, the G allele was significantly associated with increased FIB-4 score (p = 6.9 × 10-3), which was not observed in the males (p > 0.05). There was no association of the I148M variant with AST/ALT ratio nor NAFLD risk score, whether analyzed in all adults or by gender. DISCUSSION/CONCLUSION: Our findings provide additional evidence of an association of PNPLA3 I148M with several liver disease biomarkers in male and female Latinos residing in the Southwest of the United States.