👤 Clarence Hale

White matter hyperintensities (WMH) on T2-weighted brain magnetic resonance imaging (MRI) are common in aging and associated with small vessel cerebrovascular disease. Standard segmentation methods treat these lesions as uniform binary entities, fundamentally reducing WMH signal by flattening a complex spectrum of tissue damage into a single label. Most WMH methods threshold voxel intensities to estimate lesion volume, missing richer characterization achievable by combining fluid-attenuated inversion recovery (FLAIR) with diffusion MRI. We introduce Voxel-wise Correlation of Neighbors (VCON), a cross-modal framework that quantifies voxel-level relationships between intensity values on T2-weighted FLAIR scans and fractional anisotropy (FA) on diffusion MRI within individuals. VCON generates hypothesis-driven WMH labels by identifying regions where increased FLAIR signal is negatively correlated with FA, suggesting underlying microstructural damage. Using MRI data from over 2,500 participants in community-based aging cohorts, we validated VCON through multi-scale analysis, age-association modeling, scanner comparisons, and intensity-based clustering of WMH into spatially coherent zones with distinct microstructural profiles. VCON revealed a gradient of WMH signal variation that tracks with age and diffusion metrics across scanners and segmentation methods. These results demonstrate that binary WMH masks may obscure clinically important variation in lesion characteristics. VCON reframes lesion segmentation as characterizing microstructural heterogeneity, offering additional structure-informed characterization beyond conventional binary methods by leveraging multimodal MRI signal variation. Show less

To compare components of the 24-hour movement behaviors (physical activity, sedentary behavior, sleep) across sex and race/ethnic groups among a diverse sample of adolescents to identity potential gaps and opportunities for intervention. The sample consisted of 704 adolescents (15.4 ± 0.6 years; 51% Black; 53% female) from year 15 of the Future of Families and Child Wellbeing Study. Twenty-four-hour movement behaviors were measured over a week-long period using waist- and wrist-worn accelerometry. Sex, racial, and ethnic differences in 24-hour movement behaviors were examined with chi-square and t-test analyses. Female adolescents, on average, spent less time in light physical activity (LPA) and in moderate-to-vigorous physical activity (MVPA) than male adolescents. Additionally, female adolescents spent more time in sedentary behavior and had longer daily total sleep time than adolescent males. Black adolescents had higher average LPA than White adolescents. Black adolescents also had higher average MVPA and LPA than Hispanic/Latino adolescents. Hispanic/Latino youth had longer total sleep time, and more sedentary time than Black youth. No other significant differences were observed across these demographic groups. There is a continued need for interventions to promote physical activity and sleep among adolescents, with a particular focus on increasing sleep duration among boys and physical activity among girls and Hispanic/Latino adolescents. Show less

Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) regulate glucose and energy homeostasis. Targeting both pathways with GIP receptor (GIPR) antagonist antibody (GIPR-Ab) and GLP-1 receptor (GLP-1R) agonist, by generating GIPR-Ab/GLP-1 bispecific molecules, is an approach for treating obesity and its comorbidities. In mice and monkeys, these molecules reduce body weight (BW) and improve many metabolic parameters. BW loss is greater with GIPR-Ab/GLP-1 than with GIPR-Ab or a control antibody conjugate, suggesting synergistic effects. GIPR-Ab/GLP-1 also reduces the respiratory exchange ratio in DIO mice. Simultaneous receptor binding and rapid receptor internalization by GIPR-Ab/GLP-1 amplify endosomal cAMP production in recombinant cells expressing both receptors. This may explain the efficacy of the bispecific molecules. Overall, our GIPR-Ab/GLP-1 molecules promote BW loss, and they may be used for treating obesity. Show less

Glioblastoma (GBM) displays marked cellular and metabolic heterogeneity that varies among cellular microenvironments within a tumor. Metabolic targeting has long been advocated as a therapy against many tumors including GBM, but how lipid metabolism is altered to suit different microenvironmental conditions and whether cancer stem cells (CSCs) have altered lipid metabolism are outstanding questions in the field. We interrogated gene expression in separate microenvironments of GBM organoid models that mimic the transition between nutrient-rich and nutrient-poor pseudopalisading/perinecrotic tumor zones using spatial-capture RNA-sequencing. We revealed a striking difference in lipid processing gene expression and total lipid content between diverse cell populations from the same patient, with lipid enrichment in hypoxic organoid cores and also in perinecrotic and pseudopalisading regions of primary patient tumors. This was accompanied by regionally restricted upregulation of hypoxia-inducible lipid droplet-associated (HILPDA) gene expression in organoid cores and pseudopalisading regions of clinical GBM specimens, but not lower-grade brain tumors. CSCs have low lipid droplet accumulation compared to non-CSCs in organoid models and xenograft tumors, and prospectively sorted lipid-low GBM cells are functionally enriched for stem cell activity. Targeted lipidomic analysis of multiple patient-derived models revealed a significant shift in lipid metabolism between GBM CSCs and non-CSCs, suggesting that lipid levels may not be simply a product of the microenvironment but also may be a reflection of cellular state. CSCs had decreased levels of major classes of neutral lipids compared to non-CSCs, but had significantly increased polyunsaturated fatty acid production due to high fatty acid desaturase (FADS1/2) expression which was essential to maintain CSC viability and self-renewal. Our data demonstrate spatially and hierarchically distinct lipid metabolism phenotypes occur clinically in the majority of patients, can be recapitulated in laboratory models, and may represent therapeutic targets for GBM. Show less

Glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) has been identified in multiple genome-wide association studies (GWAS) as a contributor to obesity, and GIPR knockout mice are protected against diet-induced obesity (DIO). On the basis of this genetic evidence, we developed anti-GIPR antagonistic antibodies as a potential therapeutic strategy for the treatment of obesity and observed that a mouse anti-murine GIPR antibody (muGIPR-Ab) protected against body weight gain, improved multiple metabolic parameters, and was associated with reduced food intake and resting respiratory exchange ratio (RER) in DIO mice. We replicated these results in obese nonhuman primates (NHPs) using an anti-human GIPR antibody (hGIPR-Ab) and found that weight loss was more pronounced than in mice. In addition, we observed enhanced weight loss in DIO mice and NHPs when anti-GIPR antibodies were codosed with glucagon-like peptide-1 receptor (GLP-1R) agonists. Mechanistic and crystallographic studies demonstrated that hGIPR-Ab displaced GIP and bound to GIPR using the same conserved hydrophobic residues as GIP. Further, using a conditional knockout mouse model, we excluded the role of GIPR in pancreatic β-cells in the regulation of body weight and response to GIPR antagonism. In conclusion, these data provide preclinical validation of a therapeutic approach to treat obesity with anti-GIPR antibodies. Show less

Owing to the loss of heterochromatin integrity that occurs during thyroid tumorigenesis, the expression of Heterochromatin Protein 1 isoforms HP1α and HP1β was assessed by immunohistochemistry in 189 thyroid tumors and non-neoplastic tissues. Expression of HP1β was significantly decreased in all thyroid lesions, except in follicular adenomas, when compared with matched adjacent normal tissue. This loss of HP1β expression may in part be caused by microRNA dysregulation. An example is miR-205, a microRNA that is abundantly upregulated in thyroid carcinomas and shown to reduce the expression of HP1β. In contrast to HP1β, HP1α expression was only reduced in metastatic carcinomas and poorly differentiated lesions. These results suggest the reduction of HP1β followed by a decrease in HP1α contributes to the pathogenesis of thyroid carcinomas, and their loss is a potential marker of thyroid malignancy and metastatic potential, respectively. Show less