Project description:To search for the role of microRNAs in postmenopausal osteoporosis, we used an experimental ovariectomized (OVX) mice moldel. We operated ovariectomy in 3-month-old C57BL/6 mice and collected the femurs after 6months to perform miRNA microarray analysis to identify dysregulated microRNAs.
Project description:In general, women are more susceptible to xerostomia than men. Clinical studies have indicated a noteworthy increase in the incidence of xerostomia following menopause, along with a negative correlation between saliva estrogen levels and the severity of xerostomia symptoms. Similarly, ovariectomy (OVX) in rodents not only decreases saliva secretion but also triggers pathological alterations in the SG. We used microarrays to detail the global programme of gene expression underlying OVX-mediated SG dysfuction.
Project description:To study the differentially expressed genes in postmenopausal osteoporosis , a postmenopausal osteoporosis rat model were constructed by bilateral ovariectomy. We then performed gene expression profiling analysis using data obtained from RNA-seq of the rat femur tissues.
Project description:The loss of skeletal muscle strength mid-life in females is associated with the decline of estrogen. Here, we questioned how estrogen deficiency might impact the overall skeletal muscle phosphoproteome after contraction, as force production induces phosphorylation of several muscle proteins. Phosphoproteomic analyses of the tibialis anterior muscle after contraction in two mouse models of estrogen deficiency, ovariectomy (Ovariectomized [Ovx] vs Sham) and natural aging-induced ovarian senescence (Older Adult [OA] vs Young Adult [YA]), identified a total of 2,593 and 3,507 phosphopeptides in Ovx/Sham and OA/YA datasets, respectively. Further analysis of estrogen deficiency-associated proteins and phosphosites identified 66 proteins and 21 phosphosites from both datasets. Of these, 4 estrogen deficiency-associated proteins and 4 estrogen deficiency-associated phosphosites were significant and differentially phosphorylated or regulated, respectively. Comparative analyses between Ovx/Sham and OA/YA using Ingenuity Pathway Analysis (IPA) found parallel patterns of inhibition and activation across IPA-defined canonical signaling pathways and physiological functional analysis, which were similarly observed in downstream GO, KEGG, and Reactome pathway overrepresentation analysis pertaining to muscle structural integrity and contraction, including AMPK and calcium signaling. IPA Upstream regulator analysis identified MAPK1 and PRKACA as candidate kinases and calcineurin as a candidate phosphatase sensitive to estrogen. Our findings highlight key molecular signatures and pathways in contracted muscle suggesting that the similarities identified across both datasets could elucidate molecular mechanisms that may contribute to skeletal muscle strength loss due to estrogen deficiency.
Project description:The peri- and postmenopausal periods in women are associated with decreases in circulating estrogen levels, marked acceleration of age-related bone loss and increased risk of fracture. However, despite the clinical importance of postmenopausal bone loss, our molecular understanding of this process is incomplete. Here, we used co-expression network analysis to gain novel insight into the molecular mechanisms mediating bone loss in ovariectomized (OVX) mice, a model of human menopause. Expression profiles from intact and OVX mice from a panel of inbred strains were used to generate a co-expression network consisting of 29 modules. Genes in network module 25 were decreased by OVX in all strains. Module 25 was enriched for genes involved in the response to oxidative stress, a process known to be an upstream causal factor for OVX-induced bone loss. It was also found that module 25 homologs were co-expressed in human bone marrow and were enriched for genes with evidence of genetic association with bone mineral density (BMD) in women. Alpha synuclein (Snca) was the most highly connected “hub” genes in module 25 and its in vivo knockout resulted in a 40% reduction in OVX-induced bone loss. Furthermore, protection was associated with the targeted alteration of genes in specific network modules, including module 10. Our results identify a gene module associated with OVX-induced bone loss and demonstrate that Snca regulates ovariectomy-induced bone loss by controlling bone network dynamics.
Project description:The risk of developing glaucoma has recently been associated with the age of menopause. This study examines how age and surgical menopause via ovariectomy (OVX) impact gene expression in the posterior eye, including the sclera and optic nerve head. We examined how age and OVX impacted expression pathways linked to glaucoma, such as extracellular matrix (ECM) remodeling and TGF-β signaling. To compare these changes across different tissue regions, we also examined the retina. Using bulk RNA sequencing, we analyzed these changes in young (3-4 months) and middle-aged (9-10 months) Long-Evans rats. Our results demonstrate that both aging and OVX significantly alter gene expression in these ocular tissues. Specifically, OVX in young rats led to significant enrichment of ECM and TGF-β gene sets, while these effects were diminished in middle-aged rats, indicating an age-dependent influence. Early OVX triggered significantly enriched ECM remodeling and immune responses compared to later OVX. These findings underscore the critical role of menopause timing in modulating molecular pathways associated with glaucoma, suggesting that early menopause may heighten the risk of developing this condition. Notably, FOS was downregulated in the posterior eye and retina in aging and OVX animals. FOS is a major regulator of cell proliferation and survival, and its dysregulation may play an important role in aging and menopause for women. This study highlights the importance of considering women's health factors, such as menopause, in understanding and managing glaucoma risk.
Project description:Postmenopausal osteoporosis (PMOP) is a disease with a high prevalence in postmenopausal women and is characterized by an imbalance in bone metabolism, reduced bone mass, and increased risk of fracture due to estrogen deficiency. Jiangu granules (JG) is a compound prescription used in traditional Chinese medicine to treat PMOP. We used a 4D label-free quantitative proteomics method to explore the potential therapeutic mechanism of JG in an ovariectomy (OVX) rats’ model.
Project description:The peri- and postmenopausal periods in women are associated with decreases in circulating estrogen levels, marked acceleration of age-related bone loss and increased risk of fracture. However, despite the clinical importance of postmenopausal bone loss, our molecular understanding of this process is incomplete. Here, we used co-expression network analysis to gain novel insight into the molecular mechanisms mediating bone loss in ovariectomized (OVX) mice, a model of human menopause. Expression profiles from intact and OVX mice from a panel of inbred strains were used to generate a co-expression network consisting of 29 modules. Genes in network module 25 were decreased by OVX in all strains. Module 25 was enriched for genes involved in the response to oxidative stress, a process known to be an upstream causal factor for OVX-induced bone loss. It was also found that module 25 homologs were co-expressed in human bone marrow and were enriched for genes with evidence of genetic association with bone mineral density (BMD) in women. Alpha synuclein (Snca) was the most highly connected “hub” genes in module 25 and its in vivo knockout resulted in a 40% reduction in OVX-induced bone loss. Furthermore, protection was associated with the targeted alteration of genes in specific network modules, including module 10. Our results identify a gene module associated with OVX-induced bone loss and demonstrate that Snca regulates ovariectomy-induced bone loss by controlling bone network dynamics.