JCI insight

Even with long-term HIV treatment keeping the virus down, a damaged gut barrier may stay vulnerable—and compounds from broccoli were linked to a shift in repair signals. @JCI_Insight medicalxpress.com/news/2026-05-b…

@UCLA Behind the scenes from the Butte lab: Greg Whitehill, MD (left), and Timothy Thauland, PhD (right), the first authors of the companion papers.

@UCLA Manish J. Butte & team @UCLA report severe Valley fever occurring in males often features heightened allergy-like immunity, predisposed in some by genetic mutations, which suggests that targeted immune treatments can strengthen defenses: doi.org/10.1172/jci.in…

#ValleyFever is a respiratory infection caused by Coccidioides fungus spores that can range in severity from self-limiting to disseminated. doi.org/10.1172/jci.in… & doi.org/10.1172/jci.in… Two Research articles in this issue explore immune phenotypes from individuals with coccidioidomycosis including those with severe, life-threatening disease.

What happens when GLP-1 weight-loss drugs are stopped and then restarted? Thomas H. Leung @realthomasleung & team @PennMedicine asked this question in mice, reporting that cycling treatment made the drugs less effective over time and increased fat gain compared with continuous treatment: doi.org/10.1172/jci.in… #GLP1 #Weightloss

From earlier this week: Suggesting a simple dietary fix for hospitalized patients doi.org/10.1172/jci.in… Michael J. Morowitz @morowitzmj & team @ChildrensPgh found plant-based tube feeding helps rebuild healthy gut bacteria and restore immune cells after antibiotics in mice and humans. #GutMicrobiome #ClinicalNutrition

ICYMI: This Research Letter showcases an innovative murine model of aortic regurgitation: doi.org/10.1172/jci.in… Robert Lakin @mrlakin13 et al. use a model for graded aortic regurgitation and find the severity of AR correlates with atrial stretch and fibrillation. The figure shows post-AR mitral inflow changes consistent with restrictive left ventricular (LV) filling. #Afib #CardioX

This model summarizes the biochemical properties of WT and ΔF48 PKCγ.

Introducing a new mouse model of spinocerebellar ataxia type 14 with a clinically relevant mutation in PKCγ: doi.org/10.1172/jci.in… This issue’s Cover features work by Alexandra C. Newton & team @UCSanDiego reporting on the underlying drivers of #SCA14 and potential neuroprotection in females. The cover image shows Purkinje cell staining in the cerebellum, a cell type and brain region strongly affected by spinocerebellar ataxia type 14. Image credit: Sarah Wolfe, Yuliang Ma, and Alexandra Newton.

The rates of #OpioidUseDisorder in pregnancy have risen sharply over the last 20 years doi.org/10.1172/jci.in… Ilhem Messaoudi & team @UKYMedicine collected maternal and fetal placental tissues, finding opioid use disorder during pregnancy disrupts placenta structure and immune function with implications for adverse impacts to maternal and fetal health. The figure shows maternal opioid use disorder ± hepatitis C virus (HCV) is associated with inflammation and fetal/maternal vascular malperfusion.

Revealing a precise therapeutic target in X-linked #CentronuclearMyopathy: doi.org/10.1172/jci.in… Jocelyn Laporte & team @IGBMC perform in vivo studies of DNM2 functions in mice, identifing lipid binding as the principal driver of #MyotubularMyopathy. The image: Tibialis anterior muscle from Mtm1-/y Dnm2K562E/+ mice shows improved histology. #MuscleResearch

Epithelial TMPRSS2 impairs glucose homeostasis in obese mice by regulating ghrelin–GLP-1 receptor signaling pathway

GLP-1-based therapeutics have revolutionized anti-diabetic and anti-obesity treatments. doi.org/10.1172/jci.in… Here, Wolfram Ruf & team identify the intestinal protease TMPRSS2 as a critical regulator of #GLP1 in an obesity-induced diabetes preclinical model. The image shows colocalization of PAR2 and TMPRSS2 in the mouse small intestine. #Metabolism

Position-5–driven reorientation of an immunodominant HLA-A*24:02 SARS-CoV-2 epitope drives universal T cell escape: doi.org/10.1172/jci.in…

How can a single mutation in #SARS-CoV-2 abolish recognition by T cell receptors? doi.org/10.1172/jci.in… Andrew K. Sewell & team show that a substitution in the NF9 spike epitope flips a viral fragment, hiding it from T-cells and allowing the virus to evade an important immune response. The figure: Structural basis for position-5–driven reorientation of the NF9 peptide within HLA-A*24:02. #Immunology #ViralEvolution

What do aging, inflammation, and mechanical stretch have in common? They all set the stage for atrial fibrillation (AF). We've long studied AF risk in endurance athletes, who paradoxically develop the same atrial remodeling as elderly patients with heart disease. The culprit?

Behind the scenes from the Backx lab at York University with first author Robert Lakin @mrlakin13 doing real-time echo-derived assessments of aortic regurgitation severity, intracardiac arrhythmia vulnerability, and optical mapping assessments of arrhythmogenesis in isolated atria.

This Research Letter showcases an innovative murine model of aortic regurgitation: doi.org/10.1172/jci.in… Robert Lakin @mrlakin13 et al. use a model for graded aortic regurgitation and find the severity of AR correlates with atrial stretch and fibrillation. The figure shows post-AR mitral inflow changes consistent with restrictive left ventricular (LV) filling. #Afib #CardioX

@Inserm Progressive HNF1A-MODY pathophysiology revealed by a translational mouse model: doi.org/10.1172/jci.in…

Existing mouse models fail to recapitulate human disease progression in the most common form of #MonogenicDiabetes. doi.org/10.1172/jci.in… Caroline Bonner & team @Inserm present a new mouse model, revealing HNF1A-MODY diabetes involves early insulin resistance and testosterone deficiency before β-cell failure and affects multiple organs beyond the pancreas. The figure shows staining in Hnf1a+/Δe4-10 livers compared with Hnf1a+/+ livers with progressive hepatic steatosis and fibrosis.