👤 H C Martin

To compare two 16-week high-load, velocity-intentional resistance training programs-elastic bands (HL-VIRT-EB) vs. water-based (HL-VIRT-AQ)-combined with creatine or placebo supplementation on neuroplasticity, oxidative stress, inflammation, strength, physical function, cognition, and quality of life in older adults. In a randomized controlled trial, 103 community-dwelling older adults (57 women, 46 men; 68.2 ± 4.6 y) were assigned to HL-VIRT-EB + Creatine, HL-VIRT-EB + Placebo, HL-VIRT-AQ + Creatine, HL-VIRT-AQ + Placebo, Control+Creatine, or Control+Placebo. Training was performed 3×/week (60 min). Creatine was consumed daily (3 g). Outcomes included brain-derived neurotrophic factor, F2-isoprostanes (F2-iso), glutathione peroxidase (GPx), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), isokinetic strength (knee/elbow, 60°·s Both training modalities produced significant improvements in neurocognitive biomarkers, oxidative/inflammatory profiles, strength, functional performance and quality of life (p < 0.05). HL-VIRT-AQ yielded greater reductions in F2-iso and TNF-α and larger gains in functional tests compared to HL-VIRT-EB (d = 0.12-1.18), which elicited superior upper-limb strength gains. Creatine provided additional benefits, increasing GPx, reducing IL-6/TNF-α and improving strength and function when combined with exercise modalities. Creatine alone reduced F2-iso and TNF-α and improved perceived health versus placebo. High-load, velocity-intentional resistance training-on land or in water-effectively improves neurocognition, oxidative balance, inflammation, strength, function, and quality of life in older adults. Aquatic training is particularly effective for attenuating oxidative stress and inflammation. Creatine supplementation confers complementary, modality-specific benefits and supports their use in combination to high-speed resistance exercise to promote healthy aging. NCT06620666 (ClinicalTrials.gov). Show less

To systematically examine the available literature on circulating biomarkers of performance resilience in a military environment, with the goal of identifying the most promising circulating biomarkers. The construct 'resilience' is hypothesized to play an important role in increasing Special Operations Forces' and other military personnel's capacity for withstanding exposure to various military-specific stressors. However, objectively measuring resilience is challenging. Some of the most important and well-studied circulating biomarkers that affect military-specific resilience are cortisol, dehydroepiandrosterone (sulfate) [DHEA(S)], noradrenaline, serotonin, neuropeptide-Y (NPY) and brain-derived neurotrophic factor. Despite growing evidence, the available knowledge is yet to be summarized and reviewed while considering the intensity and duration of military-specific stressors, military experience, and methodological differences between studies. Cortisol, Insulin-like growth factor-1 (IGF-1), NPY and DHEA(S) provide a physiological window into military-specific resilience. In general, individuals who exhibit a pronounced but controlled biomarker response to an acute stressor, combined with a quick recovery to baseline, demonstrate physiological flexibility that is associated with greater military-specific resilience. Future research will need to determine relative thresholds for the acute stressor-related change in circulating biomarkers and relative timing to stressor, to correctly interpret 'a pronounced but controlled biomarker response' and 'quick recovery to baseline'. Show less

Microglia are the brain's resident immune cells that respond to injury and disease by transitioning between homeostatic and reactive states. These cell state transitions determine whether microglia promote or resolve inflammation in the central nervous system (CNS). In this study, we explored the role of Ca Show less

Glaucoma is a progressive neurodegenerative disease that affects retinal ganglion cells (RGCs), ultimately leading to vision loss. In this study, we investigated gene therapy-mediated transduction of RGCs and examined axonal transport changes in the optic nerve using a viral vector designed to upregulate tropomyosin receptor kinase B (TrkB) expression. TrkB expression was evaluated in retinae and optic nerves of rats following genetic intravitreal delivery of AAV2-TrkB. Axonal transport and preliminary mitochondrial changes were assessed in optic nerves by immunohistochemical staining for kinesin and voltage-dependent anion channel (VDAC), a mitochondrial component. The results revealed an approximately 30% increase in TrkB expression in the retina, which was confirmed to be vector-driven by a P2A tag attached to the TrkB protein. This increased protein expression could be seen independent of injury and in eyes with elevated intraocular pressure. Observations along the optic nerve of rats treated with AAV2-TrkB revealed elevated transport of TrkB along axons (50% in TrkB, 120% in P2A tag) and significant increases in kinesin (12%) and VDAC (16%) immunoreactivity. This study provides early indications that improving TrkB expression in the eye may increase anterograde transport of motor proteins, which in turn could improve mitochondrial transport within the optic nerve. Show less

Although increased maternal androgens, such as those in polycystic ovary syndrome (PCOS), are associated with a higher incidence of autism spectrum disorder (ASD) in offspring, a causal link has yet to be established. We assessed whether perinatal hyperandrogenization in a murine model recapitulates core ASD traits and compared this model to the maternal immune activation (MIA) model of ASD. Both models produced ASD-like phenotypes, yet they exhibited distinct behavioral subtypes and neurodevelopmental trajectories. Hyperandrogenized offspring showed greater reductions in social communication (neonatal USVs, d = 0.633-0.773; juvenile USVs, d = 1.103-1.216; social preference, d = 0.715), whereas only MIA offspring showed increased repetitive behaviors (d = 0.599). Ex vivo magnetic resonance imaging revealed volume increases in specific cortical regions in both models, with MIA additionally showing absolute cingulate cortex enlargement, and hyperandrogenized mice displaying focal increases in sexually dimorphic regions, despite a 36% reduction in overall brain volume (FDR 10%). Placentas from both groups showed reduced LIX (CXCL5), but distinct immune shifts also emerged: MIA placentas exhibited elevated IL-4 and IL-1β, whereas hyperandrogenized placentas showed increased TNFα. In neonatal brains, both conditions were associated with reduced IL-2, with MIA additionally decreasing IL-17A and IL-12p70, suggesting suppression of Th1/Th17-type cytokine signaling that normally supports proinflammatory and immune-neural interactions. DRD2 and BDNF protein were upregulated in hyperandrogenized fetal brains but downregulated with MIA. These results suggest that hyperandrogenization and MIA act through distinct mechanisms, producing subtle neurodevelopmental and behavioral differences consistent with human ASD subtypes. Show less

Elevated atherogenic lipoproteins increase risk of atherosclerotic cardiovascular disease (ASCVD), though long-term risk for adults without ASCVD who have low-normal levels has not been well described. This study used pooled data from 16,384 individuals in 3 population-based prospective cohorts. At baseline all participants were without ASCVD and were not taking lipid-lowering therapy. We evaluated ASCVD events by baseline LDL-C, non-HDL-C and apoB, including low-normal values. ASCVD risk was assessed using multivariable Cox proportional hazards. The study cohort had a mean age of 52 (SD 18) years with 56.5% women, 64.7% of White race and 35.3% of Black race. Over a median follow-up of 18.8 years, unadjusted ASCVD event incidence was similar for adults with baseline LDL-C < 70 mg/dL and 70 to 99 mg/dL, and higher with LDL-C ≥ 100 mg/dL; trends were similar for non-HDL-C and apoB categories. Compared to having baseline LDL-C 70 to 99 mg/dL, LDL-C < 70 mg/dL was associated with similar ASCVD risk (adjusted HR 1.16 [95% Confidence Interval, 95% CI 0.90-1.50]) and LDL-C ≥ 130 mg/dL was associated with higher risk (adjusted HR 1.31 [95% CI 1.14-1.50]) after multivariable adjustment; adults with non-HDL-C ≥ 160 mg/dL or apoB ≥ 90 mg/dL also had higher risk after multivariable adjustment. Among adults without ASCVD not taking lipid-lowering therapy at baseline, ASCVD risk for adults with low-normal and high-normal LDL-C, non-HDL-C and apoB was similar, and their risk remained less than in adults with elevated lipoproteins. These findings emphasize the importance of achieving normal atherogenic lipoprotein levels for primary prevention of ASCVD from early adulthood through middle age. Show less

Subjective cognitive complaints (SCC) can precede cognitive decline and are associated with demographic, exposure, lifestyle, and psychological factors. Prevalences of SCC and their correlates in individuals with repetitive head impacts (RHI) are poorly understood. This study characterized SCC in former elite American football players by frequency, mood and behavioral correlates, concordance with informant reports, and associations with neuropsychological test performance, cerebrospinal fluid (CSF), and magnetic resonance imaging (MRI) markers of neurodegeneration. Former American football players ( Rates of SCC ranged from 43 to 77% depending on the domain. Symptoms of depression, impulsivity, and anxiety were strongly associated with SCC. Self- and informant-reported SCC showed moderate inter-rater agreement. Adjusting for age, race, education, SCC are strongly associated with neuropsychiatric factors in former American football players. SCC may also be a marker of cognitive decline and neurodegeneration. Show less

The APOE-ε4 allele is the strongest genetic risk factor for late-onset Alzheimer's disease. However, APOE-ε4 is not deterministic, highlighting the need to identify additional genetic and environmental factors. APOE-ε4 has been linked to accelerated cognitive decline, so we sought to investigate genetic factors that modify APOE-ε4-associated cognitive decline. We conduct cross-ancestry APOE-ε4-stratified and interaction GWAS using harmonized cognitive data from 32,778 participants, including 29,354 non-Hispanic White and 3,424 non-Hispanic Black individuals. Our primary outcome is late-life cognition, measured using harmonized composite scores for memory, executive function, and language, modeled as continuous traits reflecting both normative cognitive aging and disease-related decline. We identify two genome-wide significant loci in APOE-ε4 carriers, reaching genome-wide significance for executive function. These loci also demonstrate nominal associations across the other domains, suggesting broad effects on cognition. In non-carriers, we identify a genome-wide significant association at ITGB8 restricted to executive function, and another locus associated with language. We further link these loci to SEMA6D, GRIN3A, and ITGB8 through expression and methylation databases. Post-GWAS analyses implicate additional genes including SLCO1A2, and DNAH11. Genetic correlation analyses reveal differences by APOE-ε4 status for immune-related traits, suggesting immune-related predispositions may exacerbate cognitive risk in APOE-ε4 carriers. Show less

CNS diseases are a prevailing cause of morbidity and mortality worldwide, and are influenced by environmental and biological factors, including genetic risk. Here, we generated genome-wide genetic data on a large cohort of brain tissue donors with in-depth clinical and neuropathological phenotyping, allowing for broad investigations into the risk and mechanisms of these neurological, neurodevelopmental, and psychiatric conditions. This resource consists of 9,663 donors with array-based genotyping and 9,543 donors with whole-genome sequencing completed. The clinical diagnoses of these donors include 148 central nervous system diseases clustered into 15 broad categories by International Classification of Diseases-10 (ICD-10) coding. These donors were collected by six repositories comprising the National Institutes of Health NeuroBioBank, with an average participant age of 60 years. While primarily older individuals of European descent, the cohort also contains younger donors and individuals from non-European backgrounds. Variants were detected in whole-genome sequencing (WGS), normalized and annotated to describe their functional impact, resulting in 171,121,209 unique variants and 1,078,774 non-silent variants. These raw and normalized data have been made available as a neurogenomics resource in the National Institute of Mental Health Data Archive (NIMH NDA) (nda.nih.gov), combined with donor-matched deep demographic and phenotypic data from the NeuroBioBank Portal (neurobiobank.nih.gov). To illustrate applications, we replicated the strong association observed in previous studies between pathogenic CAG nucleotide repeat expansions in the HTT gene with the clinical diagnosis of Huntington's disease, as well as associations of the APOE gene with Alzheimer's disease, and examined the association of polygenic risk scores with the three most common disease diagnoses in the cohort. Show less

Understanding the genetic foundations of dementia is critical to unraveling its complex molecular basis. Given that a clinical diagnosis of Alzheimer's disease (AD) dementia often results from interplay between multiple underlying neuropathologic co-morbidities, previous genome-wide association studies (GWAS) of clinically diagnosed AD are restricted in their ability to translate genetic associations to potential targeted therapeutics. The current study seeks to address these limitations by presenting the largest GWAS to date (n=12,509) of neuropathologic hallmarks of AD and AD related dementias (ADRDs). We further performed a candidate-variant analysis using loci previously identified in GWAS of clinically diagnosed AD dementia and Parkinson's disease (PD). Finally, we conducted heritability and genetic correlation analyses using linkage disequilibrium (LD) score regression. We found broad genome-wide significant associations with Clinically diagnosed Alzheimer's disease (AD) dementia is commonly associated with its hallmark pathologic changes plus neuropathologic features of prevalent co-morbid diseases such as cerebrovascular disease, Lewy body disease, and more recently discovered abnormalities in protein called TDP-43 (collectively, AD related dementias; ADRD). As a result, previous studies that associated clinical diagnosis of AD with specific genes may not tell us the whole story. For this study, we gathered autopsy and genetic data to identify relationships between genes and dementia-associated brain changes. We found some relationships between these diseases and genes that had been previously identified as contributing to clinical dementia, as well as some new relationships that had been previously unknown. We also found that some genes that had previously been identified in relation to AD were associated with different dementia-associated brain lesions. Finally, we found that the various brain lesions differ in the proportion that can be attributed to genetic vs. environmental differences. These results support that the pathway to a diagnosis of dementia can be caused by multiple factors and are an important step in beginning to identify individually based dementia treatments. Show less

Cognitive impairment is a common non-motor symptom of Parkinson's disease (PD), yet its underlying mechanisms remain poorly understood. Apolipoprotein E4 (APOE4), a genetic risk factor of Alzheimer's Disease, has been associated with PD-related cognitive impairment. However, findings are inconsistent, highlighting the need for further investigation. Neuroimaging studies have found gray matter abnormalities, mainly reductions in gray matter volume (GMV) and cortical thickness (CTh), in both cognitively impaired PD patients and APOE4 carriers. Yet, APOE4's role in these structural changes and their cognitive impact in PD is underexplored. This study aimed to determine whether APOE4 influences early structural brain differences in terms of GMV and CTh in PD prior to the emergence of cognitive dysfunction. A total of 51 PD APOE4 carriers and 120 non-carriers who were cognitively unimpaired from the Parkinson's Progression Markers Initiative (PPMI) database were included. T1-weighted MRI scans were used to calculate GMV and CTh in regions previously associated with PD-related cognitive impairment, including hippocampal subregions. Cognitive scores assessing global cognition and specific cognitive domains were used to examine associations between regions showing significant GMV or CTh group differences and cognitive performance. PD APOE4 carriers showed increased GMV in the left angular gyrus (AnG) and decreased GMV in the left nucleus accumbens (NAcc) compared to non-carriers, though neither survived multiple comparison correction. Left AnG GMV correlated with visuospatial function in both groups but did not remain significant after co-variate adjustment. Left NAcc GMV correlated with visuospatial function and working memory, but only in non-carriers even after co-variate adjustment. No group differences were observed in CTh measures and hippocampal subregion GMVs. This study suggests that APOE4 may not influence cognitive function in PD by affecting GMV and CTh. However, longitudinal analyses must confirm these observations. Show less

"SuperAgers" are oldest-old adults (ages 80+) whose memory performance more closely resembles middle-aged adults. The present study examined apolipoprotein E (APOE) allele frequency in non-Hispanic Black (NHB) and non-Hispanic White (NHW) SuperAgers compared to controls and Alzheimer's disease dementia cases. In 18,080 participants from eight cohorts, harmonized clinical diagnostics and memory, executive function, and language domain scores were used to identify SuperAgers, cases, and controls across age-defined bins. NHW SuperAgers had significantly lower frequency of APOE-ε4 alleles and higher frequency of APOE-ε2 alleles compared to all cases and controls, including oldest-old controls. Similar patterns were found in a small yet substantial sample of NHB SuperAgers; however, not all comparisons with controls reached significance. We demonstrated strong evidence that APOE allele frequency relates to SuperAger status. Further research is needed with a larger sample of NHB SuperAgers to determine if mechanisms conferring cognitive resilience differ across race groups. Apolipoprotein E (APOE) allele frequency differs between SuperAgers and cases APOE allele frequency differs between non-Hispanic White SuperAgers and controls The relationship of APOE and non-Hispanic Black SuperAger status is unclear. Show less

Cognitive reserve (CR) refers to differences in the adaptability of cognitive processes that modify the impact of Alzheimer's disease (AD) pathology on cognitive performance. Currently there are no established blood-based biomarkers of CR in prodromal AD. In this study, we operationalize CR as memory reserve, defined as moderation (attenuation) of the CSF pTau181-memory association. DNA methylation (DNAm) integrates genetic and environmental influences and may capture biological processes that mitigate the impact of AD pathology on memory. We aimed to identify blood DNAm loci that moderate the association between cerebrospinal fluid (CSF) phosphorylated tau (pTau181) and memory in mild cognitive impairment (MCI). We also sought to determine if a DNAm-based signature of memory reserve predicts future memory decline. We analyzed 92 amyloid positive MCI participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) with blood DNAm, CSF pTau181, and memory scores (PHC_MEM) collected at the same visit. We first regressed memory scores on covariates (age, sex, number of After removing CpGs with low variability, we identified 6 CpGs with suggestive significance for DNAm×pTau181 interaction ( Blood DNAm patterns that moderate the pTau-memory relationship capture biology underlying memory reserve involving synaptic, vascular, immune, and metabolic pathways, and can be summarized into an MRS that predicts longitudinal memory trajectories in MCI. These findings support blood DNAm as a promising, non-invasive biomarker of cognitive resilience to AD pathology. Show less

BackgroundPrevious whole exome and whole genome sequencing (WES/WGS) studies identified genome-wide significant associations for late-onset Alzheimer's disease (AD) with rare variants but highlighted the need for larger samples.ObjectiveIdentify associations of rare coding variants with AD risk in a large-scale, multi-ancestry exome-wide.MethodsWe combined non-overlapping portions of the Alzheimer's Disease Sequencing Project (ADSP) WES (n = 18 717) and WGS (n = 35 014) datasets obtaining a sample (n = 34 202) including participants ages ≥ 60 from four genomic similarity clusters consistent with European ancestry (EA, 9 744 AD cases and 9 095 controls), African American (AA, 1 944 AD cases and 4 215 controls), Caribbean Hispanic (CH 2 344 AD cases and 3 465 controls), and Native American Hispanic (NAH 743 AD cases and 2 652 AD controls) populations. Association of AD with 253,421 bi-allelic variants with minor allele count ≥ 20 in the total sample and each population group was evaluated using GENESIS. Gene-based tests comprising predicted moderate and high-impact variants were performed using SAIGE.ResultsNovel study-wide significant associations (p < 1.97 × 10 Show less

Childhood obesity is associated with alterations in lipoprotein metabolism and increased oxidative stress, assessed by lipid peroxidation products, reactive oxygen species (ROS) and nitric oxide (NO) levels, oxidized/reduced glutathione (GSH/GSSG) ratio, and the activities of superoxide dismutase (SOD) and catalase. High-density lipoproteins (HDL) play an antioxidant role, conditioned by cholesteryl ester transfer protein (CETP), paraoxonase (PON) 1, lecithin:cholesterol acyltransferase (LCAT), lipoprotein-associated phospholipase A This study aims to evaluate HDL antioxidant capacity in children and adolescents with obesity and the status of its conditioning factors. Thirty children and adolescents, 15 with obesity and 15 normal-weight controls were studied in a cross-sectional observational study. Lipid profile and high-sensitivity C-reactive protein were assessed using standardized methods. Lipid peroxidation products, ROS, NO, GSH and GSSG levels, and catalase, SOD, CETP, LCAT, PON 1 (PON and arylesterase [ARE]) and Lp-PLA Children with obesity showed lower HDL cholesterol and apo A-I levels (P < .01), reduced CETP (P < .05), ARE (Lp-PLA Children and adolescents with obesity exhibited reduced HDL antioxidant activity, alterations in its conditioning factors, intrinsic oxidative modification of HDL particles, and increased oxidative stress. These alterations may affect long-term cardiovascular risk in children and adolescents with obesity. Show less

The maternal environment during gestation influences fetal development, with long-lasting effects on postnatal health and productivity. This study evaluated the effect of prenatal heat stress (PNHS) on blood DNA methylation of dairy calves immediately after birth and whether such modifications persist into early life. Holstein calves were born to dams exposed to either PNHS (n = 36, temperature-humidity index >68, access to shade of a freestall barn) or prenatal cooling (PNTN; n = 37, access to shade and evaporative cooling) during the last 54 ± 5 d of gestation. Whole-genome enzymatic DNA methyl sequencing was performed on blood samples collected at birth (d 0; n = 3 PNHS, n = 5 PNTN) and 1 wk post-weaning (d 63 of age; n = 8 PNHS, n = 8 PNTN). From birth onward, all calves were actively cooled and managed under the same conditions. At birth, 682,898 differentially methylated cytosines (DMC) were identified genome-wide. Principal component analysis using 55,304 DMC located in genes expressed in blood cells revealed a clear clustering by prenatal treatment. However, at weaning, clear clustering by treatment was no longer observed using 23,977 treatment-associated DMC in blood-expressed genes, despite 97,289 DMC persisting genome-wide from birth to weaning. Immune cell deconvolution showed only minor differences in granulocytes (d 0) and CD4/CD8 Show less

Fibroblast growth factor 23 (FGF23) is a phosphate-regulating hormone produced by osteocytes. In iron deficiency anemia (IDA) and in chronic kidney disease (CKD), FGF23 is also produced by erythroid cells. Recent studies have suggested that rising circulating FGF23 is negatively associated with erythropoiesis in IDA and CKD. However, the distinct contributions of bone- and erythroid-produced FGF23 to anemia in IDA remain unclear. Using the conditional deletion of Fgf23 in osteocytes (Fgf23Dmp1-cKO) and in erythroid cells (Fgf23HbB-cKO) in mice fed a control (Ctr) or an iron deficient (ID) diet, we first determined that in ID, osteocytes and erythroid cells are distinct sources of circulating intact FGF23 (iFGF23) and FGF23 cleaved peptides, respectively. We further show that erythroid-specific deletion of Fgf23 corrected anemia in ID mice, and overexpression induced anemia in Ctr mice unlike osteocyte-specific deletion or overexpression of Fgf23. Importantly, erythroid-specific deletion of Furin (FurinHbB-cKO), the enzyme responsible for FGF23 cleavage, led to increased production of iFGF23 from erythroid cells and aggravated ID-induced anemia. iFGF23 also dose-dependently blocked the differentiation of erythroid progenitors in culture triggering mitochondrial dysfunction leading to impaired erythropoiesis. These effects were fully suppressed by co-treatment with an FGFR1 inhibitor. Finally, erythroid-specific deletion of Fgf23 in an animal model of progressive CKD prevented the development of anemia of CKD. In aggregate, our results show that erythroid-expressed FGF23 is a negative regulator of erythropoiesis that contributes to anemia via direct paracrine FGFR1 activation in erythroid precursors. Show less

Building on the identification of ABCB5 as a marker of limbal stem cells (LSCs), this study examines CD63, a newly identified molecule co-expressed with ABCB5 in limbal epithelial cells, to define its role in maintaining corneal epithelial cell identity. RNA sequencing (RNA-seq) was performed on flow cytometry-sorted Abcb5-positive and Abcb5-negative murine corneal epithelial cells. CD63 expression in human corneal tissue was assessed by immunostaining. CD63 was silenced in cultured human limbal epithelial cells using siRNA-mediated knockdown and resulting molecular and cellular changes were analyzed by qRT-PCR, flow cytometry, RNA-seq, Western blotting, and cell proliferation assays. RNA-seq analysis revealed increased expression of LSC markers, including Krt15, Krt6b, Fgfr1, Gpha2, Ifitm3, Ifitm1, and Cd63, and decreased expression of differentiation-associated markers, such as Krt12, Gja1, and Ovol1 in Abcb5-positive cells. Immunostaining of human corneal tissue demonstrated strong CD63 expression localized to the limbal region. Knockdown of CD63 in cultured human limbal epithelial cells resulted in reduced cell proliferation and significantly decreased expression of corneal epithelium-enriched genes, including KRT12, CLU, ALDH1A1, ALDH3A1, TGFBI, and MYEOV. Notably, CD63 knockdown led to an approximately 50% reduction in expression of PAX6, a key transcriptional regulator of corneal epithelial identity. CD63 is highly expressed in the human limbus and is required for maintaining cell proliferation and the expression of corneal epithelium-specific proteins, likely through regulation of PAX6. These findings establish CD63 as a functionally important component of limbal stem cell biology and a key contributor to corneal epithelial homeostasis. Show less

Phosphatidic acid (PA) is increasingly recognized as an important endogenous regulator of cell proliferation and migration, playing relevant roles in physiology and pathology. However, the potential and prominence of extracellular PA in controlling cell functions are not so well established. The present review article has been undertaken to update and discuss the latest findings on extracellular PA as regulator of cell homeostasis, with special attention being paid to its role in the regulation of cell growth and migration. Specifically, exogenous PA potently stimulates myoblast proliferation and lung cancer cell migration, pointing to a critical role of this glycerophospholipid in the regulation of muscle cell regeneration and lung cancer dissemination. Interestingly, both of these actions are mediated through interaction of PA with lysophosphatidic acid (LPA) receptors and the subsequent activation of different signal transduction pathways. In particular, PA induces mitogen-activated protein kinase kinase (MEK)/extracellularly regulated kinases (ERK) 1 and 2, phosphatidylinositol 3-kinase (PI3K)/Akt, focal adhesion kinase (FAK)/Rac1, and Janus kinase-2 (JAK2)/signal transducer and activator of transcription 3 (STAT3). These findings may contribute to a better understanding of muscle cell biology and may help to develop new therapeutic strategies to treat lung cancer dissemination. Show less

Ischemic stroke (IS) remains a leading cause of long-term disability and mortality worldwide, with recovery outcomes shaped by the interplay between acute vascular injury, pre-existing comorbidities, and individual molecular profiles. Common risk factors-such as diabetes mellitus, atrial fibrillation, hypertension, and dyslipidemia-not only increase stroke susceptibility but also impair neurovascular repair by perpetuating systemic inflammation, endothelial dysfunction, and impaired neuroplasticity. Aging remains an underexplored determinant of epigenetic remodeling in stroke. Beyond these clinical determinants, genetic and epigenetic mechanisms contribute substantially to stroke heterogeneity. Genome-wide association studies (GWAS) have identified loci such as HDAC9, PATJ, PTCH1, and ABO that modulate inflammation, oxidative stress, and vascular remodeling. Complementary epigenetic pathways, including DNA methylation, histone acetylation, and circular RNAs (circRNAs), dynamically regulate gene expression in response to ischemia and comorbid influences, encoding a persistent "molecular memory" that shapes both injury and repair. Functional studies reveal that circRNAs orchestrate apoptosis, angiogenesis, and synaptic remodeling, while selective DNMT and HDAC inhibition can restore neurovascular integrity in experimental models. Recent multi-omics and longitudinal approaches demonstrate that these molecular signatures evolve across acute, subacute, and chronic phases of recovery, yet clinical translation remains limited. Aging and chronic comorbidities further modify epigenetic programs, reducing repair capacity. Although genotype-guided antiplatelet therapy illustrates the feasibility of personalized stroke care, broader genomics- and epigenetics-informed interventions require rigorous validation. This review integrates current knowledge on the interplay between vascular comorbidities, genetic predisposition, and epigenetic regulation in shaping stroke recovery. Understanding these interactions is essential for developing precision medicine approaches that enhance functional outcomes and reduce recurrence in stroke survivors.Integrating multi-omics profiling with comorbidity stratification, functional validation, and longitudinal biomarker tracking will be pivotal to achieving actionable precision medicine and improving outcomes in stroke survivors. Show less

Focal damage to articular cartilage incurred during joint injuries frequently progresses to post-traumatic osteoarthritis (PTOA) due to the limited intrinsic repair capacity of cartilage. Chondrogenic progenitor cells (CPCs) residing within the cartilage can contribute to repair if effectively recruited and activated. Early interventions that enhance CPC homing and their subsequent chondrogenesis offer a regenerative strategy to prevent PTOA progression, addressing the current lack of effective early clinical therapies. GDF5 stands out as a key protein involved in cartilage development, yet its potential to mobilize CPC-mediated regeneration remains underexplored. We evaluated the effects of GDF5 on CPC migration, proliferation, chondrogenic differentiation, and anti-catabolic activity using in vitro CPC models. To assess CPC chemotaxis in a clinically relevant biomaterial context, GDF5 was incorporated into a hyaluronic acid/fibrin interpenetrating network (IPN) hydrogel and tested in an ex vivo cartilage defect model. GDF5 acted as a potent chemoattractant for CPCs, promoting their recruitment toward cartilage defects when delivered via a hyaluronic acid/fibrin IPN hydrogel in an ex vivo model. GDF5 also enhanced CPC proliferation, consistent with activation of a glycolysis-associated transcriptional program. In addition, GDF5 significantly upregulated chondrogenic markers, including SOX9, COL2a1, and ACAN, and elevated extracellular matrix components in CPCs, potentially through activation of the PI3K/AKT signaling pathway. Furthermore, GDF5 reduced expression of a key catabolic enzyme ADAMTS5, possibly through the WWP2/miR-140 axis. These findings highlight the versatile role of GDF5 on endogenous CPCs. When combined with a hydrogel platform, GDF5 may serve as an early therapeutic strategy to convert injured cartilage from a passive site of degeneration into one of active regeneration. Show less

The genetic component of early-onset Alzheimer disease (EOAD), accounting for ~10% of all Alzheimer's disease (AD) cases, is largely unexplained. Recent studies suggest that EOAD may be enriched for variants acting in the lipid pathway. The current study examines the shared genetic heritability between EOAD and the lipid pathway using genome-wide multi-trait genetic covariance analyses. Summary statistics were obtained from the GWAS meta-analyses of EOAD by the Alzheimer's Disease Genetics Consortium (n=19,668) and five blood lipid traits by the Global Lipids Genetics Consortium (n=1,320,016). The significant results were compared between the EOAD and lipids GWAS and genetic covariance analyses were performed via SUPERGNOVA. Genes in linkage disequilibrium (LD) with top EOAD hits in identified regions of covariance with lipid traits were scored and ranked for causality by combining evidence from gene-based analysis, AD-risk scores incorporating transcriptomic and proteomic evidence, eQTL data, eQTL colocalization analyses, DNA methylation data, and single-cell RNA sequencing analyses. Direct comparison of GWAS results showed 5 loci overlapping between EOAD and at least one lipid trait harboring APOE, TREM2, MS4A4E, LILRA5, and LRRC25. Local genetic covariance analyses identified 3 regions of covariance between EOAD and at least one lipid trait. Gene prioritization nominated 3 likely causative genes at these loci: ANKDD1B, CUZD1, and MS4A64.The current study identified genetic covariance between EOAD and lipids, providing further evidence of shared genetic architecture and mechanistic pathways between the two traits. Show less

Amyloidosis derived from apolipoprotein C-II (AApoCII) is a recently discovered, rare form of amyloidosis. Data on clinical presentations and natural history are very limited. This study defines the clinicopathologic, proteomic, and outcome characteristics of renal AApoCII. Case series. Twenty-five renal AApoCII cases were identified from the Mayo Clinic Tissue Proteomics Laboratory archives from January 2008 through January 2024. All patients were White, 19 were≥65 years old at diagnosis, and 18 were female. Seven had a family history of chronic kidney disease (CKD). Patients presented with proteinuria (median 3.3g/day) and reduced kidney function (n=16; median creatinine, 1.6mg/dL). No patients had clinical evidence of other organ involvement by amyloidosis or features of monogenic hypertriglyceridemia. Histologically, amyloid deposits were often weakly positive for Congo red and involved glomeruli in all cases (with a nodular pattern in 22), whereas extraglomerular involvement was less common and generally mild. Proteomic analysis revealed abundant spectra for Apo C-II and for all 3 amyloid signature proteins (apolipoprotein E, apolipoprotein A-IV, and serum amyloid P) in all cases and detected an Apo C-II variant in 14 (K19T [p.Lys41Thr] in 12 and E47V [p.Glu69Val] in 2). Among 22 patients with follow-up information available, there were 12 end-stage kidney disease (ESKD) events and 2 deaths without ESKD during an average follow-up period of 75.5±12.5 (SE) months. Retrospective design, small sample size, APOC2 gene sequencing performed in a smaller subset. AApoCII mostly affects the kidney and manifests in the elderly with proteinuria and CKD. A minority of these patients had a family history of kidney disease. Kidney failure occurred in about half, whereas overall survival was more favorable. Amyloidosis derived from apolipoprotein C-II (AApoCII) is very rare, and data on clinicopathologic and outcome characteristics are scant. This study of 25 patients with AApoCII diagnosed by mass spectrometry at the Mayo Clinic Tissue Proteomics Laboratory revealed that most patients were elderly White females who presented with proteinuria and reduced kidney function, without involvement of other organs. A family history of kidney disease was often lacking. Pathologically, most cases exhibited nodular glomerular involvement. Proteomic analysis revealed abundant protein spectra for Apo C-II and amyloid signature proteins, and identified an Apo C-II variant in over half of cases (most commonly the p.Lys41Thr variant). The cumulative incidence of kidney failure was over 50% at 5 years follow-up. Only 4 deaths occurred over an average follow-up period of 76 months. Show less

Type 2 diabetes (T2D) is a complex metabolic disorder driven by genetic and environmental factors. While genome-wide association studies (GWAS) have identified numerous T2D-associated variants, many remain functionally uncharacterized. Integration of GWAS with molecular phenotyping offers a path to revealing biological relevance. We investigated the influence of GWAS-variants, including sub-threshold T2D-associated variants (GWAS p-value ≤ 0.0001), on gene and protein expression to assign functional relevance. Genetic variants associated with T2D in the GWAS Catalog and present in our whole-genome sequencing (WGS) data were used to perform expression quantitative trait loci (eQTL) analysis in 242 whole-blood mRNA-sequenced samples. The same variants were used to perform protein quantitative trait loci (pQTL) analysis in a set of 362 plasma samples profiled on the Olink platform. For each analysis, the datasets were randomly split into discovery and validation subsets. Associations between variants and mRNA or protein levels were tested by multiple linear regression, and only QTLs that reached a false discovery rate adjusted p-value ≤ 0.05 in the discovery dataset and replicated in the validation dataset (p ≤ 0.05) with same direction of effect were carried forward. QTL-linked mRNAs and proteins were subsequently evaluated for their relationship with T2D status to connect them with T2D pathophysiology. We identified 1,291 eQTLs linked to 97 mRNAs and 1,273 pQTLs linked to 22 proteins. Among these, 10 mRNAs and 5 proteins were differentially expressed between non-diabetic and diabetic individuals. Notably, LPL, APOBR, APOM (lipid metabolism), NOTCH2, TREH (β-cell/endocrine regulation), and HLA-A, OAS3 (immune response) converged on three biological axes central to T2D pathophysiology. The directionality of molecular effects was consistent with known disease mechanisms, including insulin resistance (LPL, APOBR), β-cell stress (TREH, NOTCH2), and chronic inflammation (OAS3). Our findings indicate that variants falling below conventional GWAS significance thresholds can have demonstrable effects on gene expression and protein levels. This underscores the importance of prioritizing biological relevance alongside statistical significance, rather than relying solely on rigid p-value cutoffs. Show less

As dementia cases continue to rise, effective prevention strategies are urgently needed. However, objective biomarkers that directly reflect lifestyle factors remain limited. Life's Essential 8 (LE8) is a composite of modifiable cardiovascular health metrics, and lower LE8 has been consistently associated with increased risk of dementia. In this study, we aimed to identify DNA methylation biomarkers associated with LE8 scores and investigate their relevance for dementia risk. We performed an epigenome-wide association study of 273 stroke-free, self-identified Hispanic adults aged 40 and older from the Northern Manhattan Study (NOMAS), a community-based urban cohort study. DNA methylation (DNAm) was assessed using Illumina MethylationEPIC arrays. Robust linear models identified CpGs associated with LE8 score, a composite score on eight health metrics including diet quality, physical activity, nicotine exposure, sleep health, body mass index, blood lipids, blood glucose, and blood pressure. Differentially methylated regions were identified by combining P-values in sliding windows while accounting for spatial correlations across the genome. We also performed functional annotation, pathway analyses, and integrative analyses with gene expression, genetic variants, brain-blood correlations, and comparisons with previous dementia studies to identify the most biologically meaningful DNAm sites. After adjusting for age, sex, APOE ε4, immune cell composition, and ancestry, we found 11 CpGs with suggestive evidence of association with LE8 (P-value < 1 × 10 Our comparison with published results showed that a number of LE8-associated DNA methylation sites are associated with dementia, highlighting the possible connection between cardiovascular health and dementia risk and pointing to potential actionable targets for dementia prevention. Moreover, DNAm biomarkers have clinical potential as objective measures to identify individuals at elevated risk, stratify participants based on biologically informed risk profiles, and monitor epigenetic responses to lifestyle interventions in dementia prevention trials. Future studies in larger and more diverse cohorts are needed to validate and refine these methylation biomarkers for clinical applications. Show less

Telomere length (TL), a biomarker of biological aging, but its association with Alzheimer's disease (AD) remains unclear. We estimated TL in whole-genome sequencing data from 35,014 Alzheimer's Disease Sequencing Project participants using TelSeq, which after quality control yielded a dataset including 6,973 persons of European ancestry (EA), 4,188 African Americans (AA), 4,005 Caribbean Hispanics (CH), and 4,170 Native American Hispanics (NAH). TL was log-transformed, adjusted for age and blood cell counts, and z-scaled. Scaled TL was dichotomized into long and short groups according to the median. An AD GWAS for the interaction of TL with variants having a minor allele count >20 was performed in each ancestry group using logistic regression models including SNP and TL main effects and a SNP×TL interaction term. AD risk was associated with shorter TL (β = -0.18, We identified variants that significantly impact AD risk through their interaction with TL, suggesting that TL maintenance pathways may be central to AD pathogenesis. Show less

Protein truncating variants (PTVs) in To identify high-priority missense variants (HPVs), we applied ‘domain mapping of disease mutations’ for the 637 unique coding In this sample, PTVs and HPVs associated with respectively a 35- and 10-fold increased risk of early onset AD and 17- and 6-fold increased risk of overall AD. The median age at onset (AAO) of PTV- and HPV-carriers was 62 and 64 years, and Our results justify a debate on whether HPV carriers should be considered for clinical counseling. The online version contains supplementary material available at 10.1186/s13024-025-00907-z. Show less

A large fraction of the genome interacts with the nuclear periphery through lamina-associated domains (LADs), repressive regions which play an important role in genome organization and gene regulation across development. Despite much work, LAD structure and regulation are not fully understood, and a mounting number of studies have identified numerous genetic and epigenetic differences within LADs, demonstrating they are not a uniform group. Here, we profile lamin B1, CBX1 (also known as HP1B), H3K9me3, H3K9me2, H3K27me3, H3K14ac, H3K27ac, and H3K9ac in MEF cell lines derived from the same mouse colony, and cluster LADs based on the abundance and distribution of these features across LADs. We find that LADs fall into three groups, each enriched in a unique set of histone modifications and genomic features. Each group is defined by a different heterochromatin modification (H3K9me3, H3K9me2, or H3K27me3), suggesting that all three of these marks play important roles in regulation of LAD chromatin and potentially of lamina association. We also discover unique features of LAD borders, including a LAD border-specific enrichment of H3K14ac. These results reveal important distinctions between LADs and highlight the rich diversity and complexity in LAD structure and regulatory mechanisms. Show less