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Van Wyk, A.

Publications and source records attributed to Van Wyk, A..

2 recordsLinked to original sources

Targeting PFKFB3 Metabolic Gatekeeping of β-Cell Dysfunctional States Enables Durable Glucose Tolerance in Type 2 Diabetes

Progressive {beta}-cell dysfunction underlies type 2 diabetes (T2D), yet existing therapies fail to correct the dysfunctional cellular states that accumulate during disease progression. We show that pharmacological inhibition of PFKFB3 markedly reduced the population of PFKFB3 dysfunctional {beta}-cells while preserving functional islet mass, consistent with selective depletion or phenotypic reprogramming of compromised {beta}-cells. In transgenic diabetic mice expressing human IAPP, PFKFB3 inhibitor AZ67 improved glucose-stimulated insulin secretion and glucose tolerance through a mechanism consistent with direct restoration of {beta}-cell function and distinct from incretin-based therapy. Critically, glycemic improvement persisted after treatment withdrawal, consistent with durable remodeling of islet functional states rather than transient pharmacological suppression. In human islet microtissues under glucotoxic and cytokine stress, AZ67 and its analogue AZ26 improved insulin secretion and proinsulin processing in a stress- and compound-dependent manner while reducing PFKFB3 dysfunctional endocrine populations. Transcriptomic profiling identified suppression of inflammatory programs and activation of cholesterol homeostasis and adaptive metabolic pathways. These findings establish PFKFB3 inhibition as a potential disease-modifying therapeutic strategy for T2D.

cell biology↗

β-Blockers for ED Presentations with Recent Cocaine Use: A Systematic Review

BackgroundCocaine produces cardiovascular toxicity through intense sympathetic stimulation and direct myocardial injury, generating presentations ranging from hypertension and tachycardia to coronary vasospasm, arrhythmia, and myocardial depression. {beta}-blockers are foundational therapies in acute coronary syndromes, yet their use after cocaine exposure remains controversial due to concerns about unopposed -adrenergic stimulation. MethodsA systematic review was conducted in accordance with PRISMA guidelines. PubMed and Google Scholar (2000-2026) were searched for observational studies of adults ([≥]18 years) presenting to acute care with recent cocaine use that compared outcomes between {beta}-blocker recipients and non-recipients. Eligible studies reported in-hospital mortality, myocardial infarction/troponin rise, clinically significant arrhythmia, or haemodynamic instability. Risk of bias was assessed using the Newcastle-Ottawa Scale, and certainty of evidence using GRADE. ResultsFour retrospective ED cohorts (n = 1,140) met inclusion criteria; 503 patients received at least one {beta}-blocker dose. Across studies, {beta}-blocker use was not associated with increased in-hospital mortality or malignant arrhythmias. Myocardial infarction was heterogeneous and sensitive to definition and timing. Haemodynamic data showed no hypertensive surge and modest systolic blood pressure reductions. Risk of bias was moderate, and certainty of evidence very low to low. ConclusionsIn typical ED presentations of recent cocaine use, {beta}-blocker administration does not appear to increase mortality, myocardial infarction, or malignant arrhythmias, and available haemodynamic data do not support a reproducible unopposed- response. However, mechanistic and preclinical evidence suggests potential harm in severe intoxication or myocardial depression. A selective, phenotype-guided approach is warranted, and prospective mechanistic studies are needed. Key PointsO_LIBeta-blockers did not increase deaths, heart attacks, or dangerous heart rhythms in adults who came to the emergency department after recent cocaine use. C_LIO_LIBlood pressure generally decreased after beta-blocker treatment, and no consistent "unopposed alpha" reaction was seen in typical presentations. C_LIO_LICaution is still needed in severe intoxication or cases with heart muscle weakness, but for most emergency presentations, beta-blockers appear safe when used appropriately. C_LI

pharmacology and toxicology↗