Project description:Ovarian aging is characterized by declines in follicular reserve and the emergence of mitochondrial dysfunction, reactive oxygen species production, inflammation, and fibrosis, which eventually results in menopause. Menopause is associated with increased systemic aging and the development of numerous comorbidities; therefore, the attenuation of ovarian aging could also delay systemic aging processes in women. Recent work has established that the anti-diabetic drug Canagliflozin (Cana), a sodium-glucose transporter 2 inhibitor, elicits benefits on aging-related outcomes, likely through the modulation of nutrient-sensing pathways and metabolic homeostasis. Given that nutrient-sensing pathways play a critical role in controlling primordial follicle activation, we sought to determine if chronic Cana administration would delay ovarian aging and curtail the emergence of pathological hallmarks associated with reproductive senescence. We found that mice receiving Cana maintained their ovarian reserve through 12 months of age, which was associated with declines in primordial follicles FoxO3a phosphorylation, a marker of activation, when compared to the age-matched controls. Furthermore, Cana treatment led to decreased collagen, lipofuscin, and T cell accumulation at 12 months of age. Whole ovary transcriptomic and proteomic analyses revealed subtle improvements, predominantly in mitochondrial function and the regulation of cellular proliferation. Pathway analyses of the transcriptomic data revealed a downregulation in cell proliferation and mitochondrial dysfunction signatures, with an upregulation of oxidative phosphorylation. Pathway analyses of the proteomic data revealed declines in signatures associated with PI3K/AKT activity and lymphocyte accumulation. Collectively, we demonstrate that Cana treatment can delay ovarian aging in mice and could potentially have efficacy for delaying ovarian aging in women.
Project description:Current models used to study skin aging, including in vivo murine models, ex vivo human skin, and in vitro 2D cell cultures, present significant limitations in replicating the complexity of chronological human skin aging. To address this gap, we developed a novel 3D human full-thickness skin aging model using primary dermal fibroblasts and epidermal keratinocytes harvested from the same aged donors (average age 80 years). Comprehensive histological, immunostaining, and transcriptomic analyses of this aging model, compared to a young 3D skin model (average age 20 years), revealed distinct hallmarks of chronological skin aging, including reduced epidermal and dermal thickness, decreased extracellular matrix content, diminished cell proliferation, and increased cellular senescence. Furthermore, 3D aging skin model also showed reduced IGF-1 expression and induction of AP1/JunB, which were consistent with observations in aged human skin. Transcriptomic profiling further identified upregulated pathways associated with extracellular matrix degradation, cellular senescence, and immune responses, aligning closely with published data from human aged skin. This novel in vitro model faithfully recapitulates several key features of chronological skin aging, offering a robust platform for studying aging mechanisms and testing therapeutic interventions. We have used microarray to study the gene expression profile of 3D skin models
Project description:Molecular mechanisms underlying aging associated impairments in learning and long-term memory storage are poorly understood. Here we leveraged an identified motor neuron L7, mediating long-term sensitization of siphon-withdrawal reflex, a form of non-associative learning in sea slug Aplysia, to assess the impact of aging on transcriptional changes during learning. RNAseq analysis of single L7 motor neuron isolated following short-term or long-term sensitization training from 8,10 and 12 months old Aplysia corresponding to mature, late mature and senescent stages have identified progressive impairments in transcriptional plasticity during aging. Specifically, we uncover modulation of the expression of multiple lncRNAs, and mRNAs encoding transcription factors, regulators of translation, RNA methylation, and cytoskeletal rearrangements during learning and their deficits during aging. Our comparative gene expression analysis also revealed the recruitment of specific transcriptional changes in two other neurons, a motor neuron L11 and giant cholinergic neuron R2 whose roles in long-term sensitization were previously not known. Taken together, our analyses establish cell type specific escalating impairments in the expression of learning and LTM relevant components of transcriptomes during aging.
Project description:Energy metabolism dysfunction is highly connected with aging. Aged mice could exhibit multiple energy metabolism disorders, such as insulin resistance, inhibition of fatty acid degradation and lipid accumulation. PPARα is a key transcriptional factor regulating genes of fatty acid β-oxidation, playing a crucial role in lipid metabolism and ATP production. However, the role of PPARα in retarding organ aging has not been fully elucidated. Herein, we investigated the beneficial effects of Omega-3 PUFAs, endogenous agonists of PPARα, in naturally aging mice, accelerated aging mice as well as several kinds of cells cultures. Moreover, we performed studies in mfat-1 transgenic mice at 24 months of age to explore the anti-aging effects of Omega-3 PUFAs. We found that Omega-3 PUFAs and fat-1 gene restored fatty acid β-oxidation and ATP production, reduced lipid accumulation, inhibited age-related pathological changes, preserved organ functions to delay aging process. Our results suggest Omega-3 PUFAs is a promising therapeutic approach to promote healthy aging in the elderly.
Project description:Objective: Aging and early degeneration of the intervertebral disc (IVD) involves the substition of notochordal cells (NCs) in the nucleus pulposus (NP) by chondrocyte-like cells (CLCs). This study investigated the gene expression profiles involved in this process using NP tissue from both non-chondrodystrophic and chondrodystrophic dogs, a species with naturally occuring IVD degeneration. Methods: Dual channel DNA microarrays were used to compare 1) healthy NP tissue, 2) NP tissue with a mixed population of NCs and CLCs, and 3) NP tissue containing solely CLCs. Canonical Wnt-signaling was validated using qPCR of relevant Wnt target genes. Caveolin-1, a known regulator of canonical Wnt signaling, was investigated further in tissue sections using qPCR and immunohistochemistry, and in cultured NCs by qPCR and immunofluorescence. Also, the NP of 3-month-old caveolin-1 knock-out mice was histopathologically evaluated and compared with wild type mice of the same age. Results: Early IVD degeneration involved significant regulations in numerous pathways, such as extracellular matrix remodeling, Bone Morphogenetic Protein- , and Wnt/beta-catenin-signaling. With regard to Wnt/beta-catenin signaling, axin2 gene expression was significantly higher in chondrodystrophic dogs compared with non-chondrodystrophic dogs. IVD degeneration involved significant downregulation of axin2 gene expression and caveolin-1 gene and protein expression. NCs showed abundant caveolin-1 expression in vivo and in vitro, whereas CLCs did not. The NP of 3-month-old WT mice were rich in viable NCs, whereas the NPs of 3-month-old caveolin-1 knock-out mice contained chondroid-like matrix with small, rounded cells, the majority of which showed morphological signs of apoptosis. Conclusions: Aging and the onset of degeneration of the IVD involve significant downregulation of canonical Wnt signaling and caveolin-1, which appears to be essential in the physiology and preservation of NCs. DNA microarrays were used to compare nucleus palposus (NP) tissue of healthy and chondrodystrophic individuals. Furthermore, the situation of the tissue was divided into three stages: NCR: notochordal cell(NC) rich; CR: tissue containing solely chondrocyte-like-cells (CLC) and T: tissue with a mixed population of NCs and CLCs. Comparisons were analysed on a 2-color platform against a common reference sample, consisting of a multitude of canine organs, including liver, spleen, kidney, lung, hart, intestine and bone.
Project description:U3A cells stably expressing wild-type STAT1 or STAT1-CC were treated with interferon beta (10U/ml) or control for 24 hours to assess effects of stat1 modifications, interferon, and the interaction on gene expression. Keywords: interferon, STAT1, STAT1-CC, STAT1CC, STAT-1C, antiviral RNA was isolated from stable U3A-STAT1 lines stably expressing wild-type STAT1 or STAT1CC, after 24 hour treatment with interferon beta (10U/ml) or control.