The Loss of Tafazzin Transacetylase Activity Is Sufficient to Drive Testicular Infertility.

Barth syndrome (BTHS) is a rare, infantile-onset, X-linked mitochondriopathy exhibiting a variable presentation of failure to thrive, growth insufficiency, skeletal myopathy, neutropenia, and heart anomalies due to mitochondrial dysfunction secondary to inherited TAFAZZIN transacetylase mutations. Although not reported in BTHS patients, male infertility is observed in several () mouse alleles and in a mutant. Herein, we examined the male infertility phenotype in a BTHS-patient-derived point-mutant knockin mouse () allele that expresses a mutant protein lacking transacetylase activity.

Cardiac Applications of CRISPR/AAV-Mediated Precise Genome Editing.

The ability to efficiently make precise genome edits in somatic tissues will have profound implications for gene therapy and basic science. CRISPR/Cas9 mediated homology-directed repair (HDR) is one approach that is commonly used to achieve precise and efficient editing in cultured cells. Previously, we developed a platform capable of delivering CRISPR/Cas9 gRNAs and donor templates via adeno-associated virus to induce HDR (CASAAV-HDR).

PDGFRA is a conserved HAND2 effector during early cardiac development.

The basic helix-loop-helix transcription factor HAND2 has multiple roles during vertebrate organogenesis, including cardiogenesis. However, much remains to be uncovered about its mechanism of action. Here, we show the generation of several hand2 mutant alleles in zebrafish and demonstrate that dimerization-deficient mutants display the null phenotype but DNA-binding-deficient mutants do not.

Changes in immunofluorescence staining during islet regeneration in a cystic fibrosis-related diabetes (CFRD) ferret model.

Background: Knockout (KO) ferrets with the cystic fibrosis transmembrane conductance regulator (CFTR) exhibit distinct phases of dysglycemia and pancreatic remodeling prior to cystic fibrosis-related diabetes (CFRD) development. Following normoglycemia during the first month of life (Phase l), hyperglycemia occurs during the subsequent 2 months (Phase Il) with decreased islet mass, followed by a period of near normoglycemia (Phase Ill) in which the islets regenerate. We aimed to characterize islet hormone expression patterns across these Phases.

Combating PDAC Drug Resistance: The Role of Ref-1 Inhibitors in Accelerating Progress in Pancreatic Cancer Research.

Pancreatic Ductal Adenocarcinoma (PDAC) remains one of the most lethal solid tumor diagnoses given its limited treatment options and dismal prognosis. Its complex tumor microenvironment (TME), heterogeneity, and high propensity for drug resistance are major obstacles in developing effective therapies. Here, we highlight the critical role of Redox effector 1 (Ref-1) in PDAC progression and drug resistance, focusing on its redox regulation of key transcription factors (TFs) such as STAT3, HIF1α, and NF-κB, which are pivotal for tumor survival, proliferation, and immune evasion.

G protein-coupled receptor 17 inhibits glucagon-like peptide-1 secretion via a Gi/o-dependent mechanism in enteroendocrine cells.

Gut peptides, including glucagon-like peptide-1 (GLP-1), regulate metabolic homeostasis and have emerged as the basis for multiple state-of-the-art diabetes and obesity therapies. We previously showed that G protein-coupled receptor 17 (GPR17) is expressed in intestinal enteroendocrine cells (EECs) and modulates nutrient-induced GLP-1 secretion. However, the GPR17-mediated molecular signaling pathways in EECs have yet to be fully deciphered.

Heterogeneous endocrine cell composition defines human islet functional phenotypes.

Phenotyping and genotyping initiatives within the Integrated Islet Distribution Program (IIDP), the largest source of human islets for research in the U.S., provide standardized assessment of islet preparations distributed to researchers, enabling the integration of multiple data types.

Polycomb group protein Mel18 inhibits hematopoietic stem cell self-renewal through repressing the transcription of self-renewal and proliferation genes.

Polycomb group (PcG) proteins play important roles in hematopoietic stem cell (HSC) self-renewal. Mel18 and Bmi1 are homologs of the PCGF subunit within the Polycomb repressive complex 1 (PRC1). Bmi1 (PCGF4) enhances HSC self-renewal and promotes terminal differentiation.

Trajectory of beta cell function and insulin clearance in stage 2 type 1 diabetes: natural history and response to teplizumab.

Aims/hypothesis: We aimed to analyse TrialNet Anti-CD3 Prevention (TN10) data using oral minimal model (OMM)-derived indices to characterise the natural history of stage 2 type 1 diabetes in placebo-treated individuals, to describe early metabolic responses to teplizumab and to explore the predictive capacity of OMM measures for disease-free survival rate.

Methods: OMM-estimated insulin secretion, sensitivity and clearance and the disposition index were evaluated at baseline and at 3, 6 and 12 months post randomisation in placebo- and teplizumab-treated groups, and, within each group, in slow- and rapid-progressors (time to stage 3 disease >2 or 2 years). OMM metrics were also compared with the standard AUC C-peptide.

Projected epidemiological trends and burden of liver cancer by 2040 based on GBD, CI5plus, and WHO data.

Incidence of liver cancer as one of the most common cancers worldwide and become the significant contributor for the mortality among cancer patients. The disease burden, risk factors, and trends in incidence and mortality of liver cancer globally was described subsequently estimated the projections of liver cancer incidence or mortality by 2040. Data regarding age-standardized incidence and mortality rates for liver cancer was obtained from multiple databases, including GLOBOCAN 2020, CI5 volumes I-XI, WHO mortality database, and Global Burden of Disease (GBD)-2019.

Beta cell extracellular vesicle PD-L1 as a novel regulator of CD8 T cell activity and biomarker during the evolution of type 1 diabetes.

Aims/hypothesis: Surviving beta cells in type 1 diabetes respond to inflammation by upregulating programmed death-ligand 1 (PD-L1) to engage immune cell programmed death protein 1 (PD-1) and limit destruction by self-reactive immune cells. Extracellular vesicles (EVs) and their cargo can serve as biomarkers of beta cell health and contribute to islet intercellular communication. We hypothesised that the inflammatory milieu of type 1 diabetes increases PD-L1 in beta cell EV cargo and that EV PD-L1 may protect beta cells against immune-mediated cell death.

Emerging insights into epigenetics and hematopoietic stem cell trafficking in age-related hematological malignancies.

Background: Hematopoiesis within the bone marrow (BM) is a complex and tightly regulated process predominantly influenced by immune factors. Aging, diabetes, and obesity are significant contributors to BM niche damage, which can alter hematopoiesis and lead to the development of clonal hematopoiesis of intermediate potential (CHIP). Genetic/epigenetic alterations during aging could influence BM niche reorganization for hematopoiesis or clonal hematopoiesis.

The gut microbiome is associated with susceptibility to febrile malaria in Malian children.

Malaria is a major public health problem, but many of the factors underlying the pathogenesis of this disease are not well understood, including protection from the development of febrile symptoms, which is observed in individuals residing in areas with moderate-to-high transmission by early adolescence. Here, we demonstrate that susceptibility to febrile malaria following Plasmodium falciparum infection is associated with the composition of the gut microbiome prior to the malaria season in 10-year-old Malian children, but not in younger children. Gnotobiotic mice colonized with the fecal samples of malaria-susceptible children were shown to have a significantly higher parasite burden following Plasmodium infection compared to gnotobiotic mice colonized with the fecal samples of malaria-resistant children.

CRISPR-Cas9-mediated homology-directed repair for precise gene editing.

CRISPR-Cas9-mediated homology-directed repair (HDR) is a versatile platform for creating precise site-specific DNA insertions, deletions, and substitutions. These precise edits are made possible through the use of exogenous donor templates that carry the desired sequence. CRISPR-Cas9-mediated HDR can be widely used to study protein functions, disease modeling, and gene therapy.

Emerging Concepts and Success Stories in Type 1 Diabetes Research: A Road Map for a Bright Future.

Type 1 diabetes treatment stands at a crucial and exciting crossroad since the 2022 U.S. Food and Drug Administration approval of teplizumab to delay disease development.

Beta cell extracellular vesicle PD-L1 as a novel regulator of CD8+ T cell activity and biomarker during the evolution of Type 1 Diabetes.

Aims/hypothesis: Surviving beta cells in type 1 diabetes respond to inflammation by upregulating programmed death-ligand 1 (PD-L1) to engage immune cell programmed death-1 (PD-1) and limit destruction by self-reactive immune cells. Extracellular vesicles (EVs) and their cargo can serve as biomarkers of beta cell health and contribute to islet intercellular communication. We hypothesized that the inflammatory milieu of type 1 diabetes increases PD-L1 in beta cell EV cargo and that EV PD-L1 may protect beta cells against immune-mediated cell death.

miR-146a-5p mediates inflammation-induced β cell mitochondrial dysfunction and apoptosis.

We previously showed that miR-146a-5p is upregulated in pancreatic islets treated with proinflammatory cytokines. Others have reported that miR-146a-5p overexpression is associated with β cell apoptosis and impaired insulin secretion. However, the molecular mechanisms mediating these effects remain elusive.