Biology subjects

Ladiges, W. C.

Publications and source records attributed to Ladiges, W. C..

14 recordsLinked to original sources

bioRxiv2026

Serum protein profiling reveals hallmark-level aging trajectories and strain-specific resilience in CB6F1J and C57BL/6J male mice.

Aging is characterized by coordinated molecular and physiological changes across multiple biological systems, yet the ability to quantify these processes non-invasively within individuals remains limited. Here, we establish a framework for quantifying hallmark-level features of aging in mice using serum protein array profiles obtained from a single blood draw. Serum protein expression was profiled in groups of CB6F1J and C57BL/6J male mice at 8 and 32 months of age and mapped to established hallmarks of aging. Hallmark-level analyses revealed coordinated, pathway-specific changes in inflammatory, vascular, intercellular signaling, metabolic, and regenerative processes, with distinct patterns observed between strains. CB6F1J mice exhibited directional shifts across multiple pathways, while C57BL/6J mice showed broader but more heterogeneous changes. Cross-strain comparisons demonstrated shared pathway-level trends alongside variable protein-level concordance. This approach enables non-terminal assessment of aging within individuals and resolves heterogeneity in aging trajectories using minimally invasive sampling. These findings support the use of circulating protein signatures to quantify biological aging and provide a framework for translating non-invasive proteome-based assessment of aging to human studies.

systems biology↗

bioRxiv2026

Middle-aged mice treated with GHK-Cu peptide administered intraperitoneally or intranasally show behavioral rescue but divergent hippocampal aging programs

Age-related cognitive decline (ARCD) is driven by conserved biological mechanisms of aging, yet no gerotherapeutic directly targets these processes in the brain. Glycyl-L-histidyl-L-lysine complexed with copper (GHK-Cu) is an endogenous peptide with regenerative and anti-inflammatory properties that declines with age. Whether its effects on cognitive aging depend on delivery route or exposure duration remains unclear. Aged C57BL/6J mice (20-21 months) received GHK-Cu (15 mg/kg) via short-term intraperitoneal (IP; 5 days) or longer-term intranasal (IN; 8 weeks) administration. Hippocampal-dependent escape learning was assessed using a spatial navigation task. Molecular effects were evaluated using hippocampal immunohistochemistry and bulk RNA sequencing. Differential gene expression was analyzed using DESeq2 with false discovery rate (FDR) correction, and pathway-level changes were assessed via gene set enrichment analysis (GSEA). IN GHK-Cu improved escape latency across Trials 2-4 in both sexes (P < 0.05), whereas IP dosing produced a transient improvement in males during Trial 2 (P < 0.05) without sustained effects or improvement in females. IN treatment increased synaptophysin in females (P < 0.001) and decreased GFAP in both sexes (P < 0.01), while IP treatment reduced TGF-{beta}, GFAP, and MCP-1 in males (P < 0.05) and decreased p21 in females (P < 0.0001). Transcriptomic analysis revealed distinct molecular programs. IN GHK-Cu induced coordinated suppression of oxidative phosphorylation (male NES -5.44, female NES -4.20; FDR < 0.0001) and MYC target pathways (female NES -4.31, FDR < 0.0001), with additional attenuation of PI3K-AKT-mTOR signaling in females (NES -3.15, FDR = 0.062). In contrast, IP treatment activated oxidative phosphorylation (female NES 4.97, FDR < 0.001), DNA repair (NES 5.58, FDR < 0.001), and MYC targets (NES 4.34, FDR = 0.002), indicating engagement of acute stress-response and repair pathways. GHK-Cu improves hippocampal-dependent learning in aged mice through distinct biological modes: IP exposure activates repair and stress-response pathways, whereas IN delivery induces sustained suppression of growth and mitochondrial metabolic signaling associated with aging biology. These findings demonstrate that functional cognitive improvement can arise from divergent molecular states and identify administrative route and exposure duration as key determinants of gerotherapeutic response.

pharmacology and toxicology↗

bioRxiv2026

A composite frailty index enables quantification of functional aging and identification of gerotherapeutic drugs in the house cricket.

Frailty, defined by progressive loss of physiological resilience, neuromuscular function, and cognitive capacity, is a central manifestation of biological aging yet remains difficult to quantify in scalable experimental systems. Here, we introduce a Composite Frailty Index (CFI) in the house cricket (Acheta domesticus) that integrates automated measures of locomotion, exploratory behavior, and freezing into a unified, quantitative framework of functional decline. Ten behavioral parameters derived from automated open-field tracking, including locomotor performance, exploratory behavior, and freezing were integrated into the CFI. Locomotor states were classified using k-means clustering (k = 2) of velocity distributions, and all features were normalized to age- or treatment-matched reference populations, discretized into quintiles, and summed to generate a 0-40 frailty score. Aging cohorts (young adult: 4-6 weeks; geriatric: 10-12 weeks, N = 103) and pharmacological cohorts treated at mid-life (8-10 weeks) with rapamycin (14 ppm), acarbose (1000 ppm), or phenylbutyrate (1000 ppm) were evaluated (N = 122). Across chronological aging cohorts, CFI increased from young adults to geriatrics in both females (d = 1.14 [95% CI: 0.53, 1.76], P = 0.0003) and males (d = -1.17 [95% CI: -1.75 to -0.59], P < 0.0001). Using pharmacological intervention cohorts, mid-life rapamycin treatment reduced late-life frailty relative to controls in both females (d = -1.31 [95% CI: -2.09, -0.53], P = 0.0017) and males (d = -1.33 [95% CI: -2.09, -0.58], P = 0.0004), whereas acarbose and phenylbutyrate produced inconclusive effects (ds = -0.54 to -0.03; Ps > 0.05). Together, these findings establish the cricket CFI as a scalable, high-throughput platform for quantifying multidimensional functional aging and prioritizing candidate geroprotective interventions based on clinically relevant endpoints beyond lifespan.

animal behavior and cognition↗

bioRxiv2025

Development of an organotypic brain slice culture model using tissues collected from geriatric mice

Ex vivo organ slice cultures are attractive models to address specific biomedical research questions because they retain complex and dynamic three dimensional architecture. In addition, they require only a few animals as tissue donors thus greatly decreasing the number needed for live animal studies. The model has been most successful using tissues from very young mice, but has generally not been considered for aging research because of the challenge of maintaining viability of tissues collected from older mice. The brain is a high impact organ in aging and age-related disease research, so it was of interest to investigate the viability and related molecular and cellular characteristics of brain slice cultures (BSCs) derived from old mice. Coronal sections of 200 m thickness were collected from the middle third of the brain of 21 month old C57BL/6JN mice, cultured in a standard media concoction for seven days, exposed to chemical stressors glucose, hydrogen peroxide, lipopolysaccharide, or sodium hypochlorite for 24 to 48 hours, and then rinsed and cultured for another seven days. Results in non-treated BSCs showed cellular viability of greater than 80 percent with specific aging pathways relatively unaffected. Chemical stressors selectively targeted pathways of aging including DNA damage, autophagy, and inflammation. These preliminary observations suggest that BSCs derived from geriatric mice have potential for research into brain aging and age-related neurodegenerative conditions, and could serve as a prototype for developing organ slice cultures for other organs collected from old mice.

cell biology↗

bioRxiv2025

The gerotherapeutic drugs rapamycin, acarbose, and phenylbutyrate extend lifespan and enhance healthy aging in house crickets.

The house cricket (Acheta domesticus) is a promising preclinical geroscience model due to its short lifespan, low maintenance, age-associated functional decline, and responsiveness to geroprotective drugs. Continuous dosing with rapamycin, acarbose, and phenylbutyrate extends lifespan; whether intermittent dosing offers similar benefits remains unknown. We tested 274 sex-matched crickets given 2-week intermittent dosing of each drug starting at mid-age (8-weeks), followed by behavioral testing at 10-weeks (geriatric stage). Assays included Y-maze olfactory discrimination, open-field exploration, and treadmill performance. Locomotor gaits were identified by velocity-based K-means clustering (silhouette > 0.5). A subset was monitored for post-treatment survival using Kaplan-Meier analysis. Olfactory preference was preserved by all drugs (ds = -1.82 to -1.28, Ps < 0.01), with strongest effects in rapamycin-treated individuals. Rapamycin-treated males matched or exceeded juvenile locomotor activity; phenylbutyrate reduced male activity (d = 1.49, P < 0.05) and acarbose increased walking-to-running ratios (d = -0.75, P < 0.05). Rapamycin increased central exploration and freezing (d = -1.55, P < 0.0001), while acarbose and phenylbutyrate increased peripheral freezing (d = -0.76, P < 0.05). Rapamycin and phenylbutyrate extended maximum running time (ds = -2.30 to -1.32, Ps < 0.0001), with sex-specific jumping gains in rapamycin-treated females and acarbose-treated males. Post-treatment lifespan was prolonged by rapamycin (HR = 0.42, P < 0.001) and reduced by acarbose in females (HRs = 2.92 to 3.03, Ps < 0.05). Intermittent rapamycin preserved survival, cognition, and locomotion, while acarbose and phenylbutyrate produced selective benefits, supporting A. domesticus as a scalable model for geroprotective drug discovery.

pharmacology and toxicology↗

bioRxiv2025

Age-related cognitive decline in house crickets reveals conserved patterns of sensory and learning deficits across the lifespan

Cognitive decline with age is characterized by impairments in learning, sensory discrimination, and decision-making. While mammalian models have advanced understanding of the neural substrates of aging, their use in large-scale behavioral studies is limited. Invertebrate models, such as the house cricket (Acheta domesticus), offer short lifespans, high throughput, and conserved neurobiological pathways but remain underexplored in geroscience. We developed a dual behavioral paradigm integrating an olfactory discrimination Y-maze and an escape learning task requiring crickets to override innate odor preferences. Adult, mid-age, and geriatric crickets were tested for sensory discrimination, associative learning, and decision speed. Morphological traits, including antennal and femoral metrics, were quantified to evaluate their influence on cognitive outcomes. Data were analyzed using ANOVA, ANCOVA, and logistic regression models. Aging impaired olfactory preference and learning success, with geriatric crickets showing reduced task acquisition and memory retention. Mid-age individuals exhibited the slowest decision-making, suggesting an early onset shift in behavioral strategy. Morphological traits predicted aspects of sensory performance and physiological resilience, such as reduced weight loss in crickets with larger femoral dimensions but did not explain age-related cognitive deficits. Olfactory decline was particularly pronounced in males, mirroring sex differences observed in human cognitive aging. House crickets exhibit hallmark features of cognitive aging, including sensory decline, learning impairments, and reduced resilience, independent of morphological deterioration. These findings establish the house cricket as a scalable invertebrate model for dissecting conserved mechanisms of neural aging and testing interventions to promote cognitive health.

neuroscience↗

bioRxiv2025

Morphological features of the domestic house cricket (Acheta domesticus) for translational aging studies

Aging alters morphology and locomotor function in diverse organisms, yet standardized model systems for studying these changes remain limited to a relatively few species. Here, we present a comprehensive analysis of age- and sex-dependent morphological variations in house crickets (Acheta domesticus), integrating refined husbandry protocols to enhance reproducibility and translational relevance. We observed progressive increases in body weight, length, and appendage dimensions with age, with pronounced sexual dimorphism emerging post-maturity. Structural adaptations, including increased femoral volume and cross-sectional area, suggest compensatory mechanisms for age-related declines in muscle efficiency, while reduced hind leg-to-body length ratios indicate potential biomechanical constraints on locomotion. Antennal growth patterns highlight prolonged sensory investment, potentially offsetting declining mobility in aging individuals. To ensure data consistency, we implemented a standardized husbandry framework incorporating self-determined photoperiods, co-housing both sexes, and controlled diet and hydration strategies. Our results underscore the necessity of harmonizing environmental conditions in gerontological research, as variations in lighting, substrate availability, and microbiome exposure may significantly impact physiological resilience and behavioral fidelity. Future work should explore the influence of microbiome diversity on lifespan and stress resilience while refining methodologies for cricket rearing from egg to adulthood. By bridging invertebrate and vertebrate aging research, this study positions house crickets as a scalable, high-throughput model for investigating age-related functional decline, behavioral plasticity, and lifespan-extending interventions. Integrating behavioral assays, biomechanical analyses, and molecular markers of aging will further elucidate the interplay between morphology, function, and longevity, advancing the utility of crickets in comparative geroscience.

animal behavior and cognition↗

bioRxiv2023

Behavioral and neuropathological features of Alzheimer's disease are attenuated in 5xFAD mice treated with intranasal GHK peptide

Efforts to find disease modifying treatments for Alzheimers disease (AD) have met with limited success in part because the focus has been on testing drugs that target a specific pathogenic mechanism. Multiple pathways have been implicated in the pathogenesis of AD. Hence, the probability of more effective treatment for AD is likely increased by using an intervention that targets more than one pathway. The naturally occurring peptide GHK (glycyl-L-histidyl-L-lysine), as a GHK-Cu complex, supports angiogenesis, remodeling, and tissue repair, has anti-inflammatory and antioxidant properties, and has been shown to improve cognitive performance in aging mice. In order to test GHK-Cu as a neurotherapeutic for AD, male and female 5xFAD transgenic mice on the C57BL/6 background at 4 months of age were given 15 mg/kg GHK-Cu intranasally 3 times per week for 3 months until 7 months of age. Results showed that intranasal GHK-Cu treatment delayed cognitive impairment, reduced amyloid plaques, and lowered inflammation levels in the frontal cortex and hippocampus. These observations suggest additional studies are warranted to investigate the potential of GHK-Cu peptide as a promising treatment for AD.

neuroscience↗

bioRxiv2023

Intranasal GHK peptide enhances resilience to cognitive decline in aging mice

Brain aging and cognitive decline are aspects of growing old. Age-related cognitive impairment entails the early stages of cognitive decline, and is extremely common, affecting millions of older people. Investigation into early cognitive decline as a treatable condition is relevant to a wide range of cognitive impairment conditions, since mild age-related neuropathology increases risk for more severe neuropathology and dementia associated with Alzheimers Disease. Recent studies suggest that the naturally occurring peptide GHK (glycyl-L-histidyl-L-lysine) in its Cu-bound form, has the potential to treat cognitive decline associated with aging. In order to test this concept, male and female C57BL/6 mice, 20 months of age, were given intranasal GHK-Cu, 15 mg/kg daily, for two months. Results showed that mice treated with intranasal GHK-Cu had an enhanced level of cognitive performance in spatial memory and learning navigation tasks, and expressed decreased neuroinflammatory and axonal damage markers compared to mice treated with intranasal saline. These observations suggest that GHK-Cu can enhance resilience to brain aging, and has translational implications for further testing in both preclinical and clinical studies using an atomizer device for intranasal delivery.

neuroscience↗

bioRxiv2023

A machine learning approach for quantifying age-related histological changes in the mouse kidney.

The ability to quantify aging-related changes in histological samples is important, as it allows for evaluation of interventions intended to effect health span. We used a machine learning architecture that can be trained to detect and quantify these changes in the mouse kidney. Using additional held out data, we show validation of our model, correlation with scores given by pathologists using the Geropathology Research Network aging grading scheme, and its application in providing reproducible and quantifiable age scores for histological samples. Aging quantification also provides the insights into possible changes in image appearance that are independent of specific geropathology-specified lesions. Furthermore, we provide trained classifiers for H&E-stained slides, as well as tutorials on how to use these and how to create additional classifiers for other histological stains and tissues using our architecture.This architecture and combined resources allow for the high throughput quantification of mouse aging studies in general and specifically applicable to kidney tissues.

pathology↗

bioRxiv2022

Intermittent treatment with elamipretide preserves exercise tolerance in aged female mice

The pathology of aging impacts multiple organ systems including the kidney, skeletal, and cardiac muscle. Long-term treatment with the mitochondrial targeted peptide elamipretide has previously been shown to improve in vivo mitochondrial function in aged mice that is associated with increased fatigue resistance and treadmill performance, improved cardiovascular diastolic function, and glomerular architecture of the kidney. However, elamipretide is a short tetrameric peptide that is not orally bioavailable limiting its routes of administration. This study tested whether twice weekly intermittent injections of elamipretide could recapitulate the same functional improvements as continuous long-term infusion. We found that intermittent treatment with elamipretide for 8 months preserved endurance running in mice, skeletal muscle force production, and left ventricular mass but did not affect heart or kidney function as previously reported using continuous treatment.

physiology↗

bioRxiv2022

A cocktail of rapamycin, acarbose and phenylbutyrate prevents age-related cognitive decline in mice by altering aging pathways

Aging is a primary risk factor for cognitive dysfunction and exacerbates multiple biological processes in the brain, including but not limited to nutrient sensing dysregulation, insulin sensing dysfunction and histone deacetylation. Therefore, pharmaceutical intervention of aging targeting several distinct but overlapping pathways provides a basis for testing combinations of drugs as a cocktail. A recent study showed that middle-aged mice treated with a drug cocktail of rapamycin, acarbose, and phenylbutyrate for three months had increased resilience to age related cognitive decline. This finding provided the rationale to investigate the comprehensive transcriptomic and molecular changes within the brain of mice that received this cocktail treatment or control substance. Transcriptome profiles were generated through RNA sequencing and pathway analysis was performed by gene set enrichment analysis to evaluate the overall RNA message effect of the drug cocktail. Molecular endpoints representing aging pathways were measured through immunohistochemistry to further validate the attenuation of brain aging in the hippocampus of mice that received the cocktail treatment, each individual drug or controls. Results indicated that biological processes that enhance aging were suppressed, while autophagy was increased in the brains of mice given the drug cocktail. The molecular endpoint assessments indicated that treatment with the drug cocktail was overall more effective than any of the individual drugs for relieving cognitive impairment by targeting multiple aging pathways.

systems biology↗

bioRxiv2021

Short term treatment with a cocktail of rapamycin, acarbose and phenylbutyrate slows aging in mice

Pharmaceutical intervention of aging requires targeting multiple pathways, thus there is rationale to test combinations of drugs each targeting different but overlapping processes. In order to determine if combining drugs previously shown to improve lifespan would have greater impact than any individuyal drug, a diet containing rapamycin at 14 ppm, acarbose at 1000 ppm, and phenylbutyrate at 1000 ppm was fed to 20-month-old C57BL/6 and HET3 4-way cross mice of both sexes for three months. Mice fed the cocktail diet showed a strain and gender-dependent phenotype consistent with healthy aging including decreased body fat and blood glucose, improved cognition, and increased grip strength and walking ability compared to mice fed individual drug or control diets. A cocktail diet containing [1/2] dosing of each compound was overall less effective than the full dose. The composite age-related lesion score of heart, lungs, liver and kidney was decreased in mice fed the cocktail diet compared to mice fed individual drug or control diets suggesting an interactive advantage of the three drugs. Senescence and inflammatory cytokine levels in kidneys from mice fed the cocktail diet were lower than in kidneys from mice fed control diet, and consistent with low expression levels in kidneys from young untreated mice, suggesting the cocktail diet delayed aging partly by senolytic and anti-inflammatory effects.

systems biology↗

bioRxiv2020

Adverse neurological effects of short-term sleep deprivation in aging mice are prevented bySS31 peptide

Sleep deprivation is a potent stress factor that disrupts regulatory pathways in the brain resulting in cognitive dysfunction and increased risk of neurodegenerative disease with increasing age. Prevention of the adverse effects of sleep deprivation could be beneficial in older individuals by restoring healthy brain function. We report here on the ability of SS31, a mitochondrial specific peptide, to attenuate the negative neurological effects of short-term sleep deprivation in aging mice. C57BL/6 female mice, 20 months old, were subcutaneously injected with SS31 (3mg/kg) or saline daily for 4 days. Sleep deprivation was 4 hours daily for the last 2 days of SS31 treatment. Mice were immediately tested for learning ability followed by collection of brain and other tissues. In sleep deprived mice treated with SS31, learning impairment was prevented, brain mitochondrial ATP levels and synaptic plasticity regulatory proteins were restored, and ROS and inflammatory cytokines levels were decreased in the hippocampus. The observations suggest possible therapeutic benefits of SS31 for alleviating adverse neurological effects of acute sleep loss.Competing Interest StatementThe authors have declared no competing interest.View Full Text

pathology↗