Hormone replacement therapy did not alleviate temporomandibular joint inflammatory pain in ovariectomized rats.

This study had the aim of examining the relationships between variations in estrogen levels resulting from ovariectomy, and estrogen hormone replacement therapy (HRT) in rats subjected to an orofacial inflammatory pain model. Eighty adult female Wistar rats were initially divided into 2 groups: Sham or ovariectomy (OVX-D1). Seven days later (D7), the rats were subjected to an unilateral infiltration of Freund's Complete Adjuvant (CFA) or saline solution into the right temporomandibular joint (TMJ). Then, rats received 17ß-estradiol (28 µg/kg/day) or placebo for 21 days (D10-D31). Nociception was evaluated by the von Frey (VF) and the Hot Plate (HP) tests, and depressive-like behavior by the Forced Swimming (FS) test. On D32 all rats were euthanized and serum, hippocampus and brainstem were collected. The CFA groups presented a mechanical hyperalgesia until day 21 (p ≤ 0.05). No differences were observed among groups in the HP (p = 0.735), and in the immobility and swimming time of the FS (p = 0.800; p = 0.998, respectively). In the brainstem, there was a significant difference in the TNF-ɑ levels (p = 0.043), and a marginal significant difference in BDNF levels (p = 0.054), without differences among groups in the hippocampal BDNF and TNF-ɑ levels (p = 0.232; p = 0.081, respectively). In conclusion, the hormone replacement therapy did not alleviate orofacial pain in ovariectomized rats. However, there is a decrease in brainstem TNF-ɑ levels in the animals submitted to both models, which was partially reverted by HRT.

Investigating the Impact of Intracerebroventricular Streptozotocin on Female Rats with and without Ovaries: Implications for Alzheimer's Disease.

To contribute to research on female models of Alzheimer's disease (AD), our aim was to study the effect of intracerebroventricular (ICV) injection of streptozotocin (STZ) in female rats, and to evaluate a potential neuroprotective action of ovarian steroids against STZ. Female rats were either ovariectomized (OVX) or kept with ovaries (Sham) two weeks before ICV injections. Animals were injected with either vehicle (artificial cerebrospinal fluid, aCSF) or STZ (3 mg/kg) and separated into four experimental groups: Sham + aCSF, Sham + STZ, OVX + aCSF and OVX + STZ. Nineteen days post-injection, we assessed different behavioral aspects: burying, anxiety and exploration, object recognition memory, spatial memory, and depressive-like behavior. Immunohistochemistry and Immunoblot analyses were performed in the hippocampus to examine changes in AD-related proteins and neuronal and microglial populations. STZ affected burying and exploratory behavior depending on ovarian status, and impaired recognition but not spatial memory. STZ and ovariectomy increased depressive-like behavior. Interestingly, STZ did not alter the expression of ß-amyloid peptide or Tau phosphorylated forms. STZ affected the neuronal population from the Dentate Gyrus, where immature neurons were more vulnerable to STZ in OVX rats. Regarding microglia, STZ increased reactive cells, and the OVX + STZ group showed an increase in the total cell number. In sum, STZ partially affected female rats, compared to what was previously reported for males. Although AD is more frequent in women, reports about the effect of ICV-STZ in female rats are scarce. Our work highlights the need to deepen into the effects of STZ in the female brain and study possible sex differences.

Estrogen deficiency reduces maximal running capacity and affects serotonin levels differently in the hippocampus and nucleus accumbens in response to acute exercise.

Introduction: Estrogen deficiency is associated with unfavorable changes in body composition and metabolic health. While physical activity ameliorates several of the negative effects, loss of ovarian function is associated with decreased physical activity levels. It has been proposed that the changes in brain neurochemical levels and /or impaired skeletal muscle function may underlie this phenomenon. Methods: We studied the effect of estrogen deficiency induced via ovariectomy (OVX) in female Wistar rats (n = 64). Rats underwent either sham or OVX surgery and were allocated thereafter into four groups matched for body mass and maximal running capacity: sham/control, sham/max, OVX/control, and OVX/max, of which the max groups had maximal running test before euthanasia to induce acute response to exercise. Metabolism, spontaneous activity, and maximal running capacity were measured before (PRE) and after (POST) the surgeries. Three months following the surgery, rats were euthanized, and blood and tissue samples harvested. Proteins were analyzed from gastrocnemius muscle and retroperitoneal adipose tissue via Western blot. Brain neurochemical markers were measured from nucleus accumbens (NA) and hippocampus (HC) using ultra-high performance liquid chromatography. Results: OVX had lower basal energy expenditure and higher body mass and retroperitoneal adipose tissue mass compared with sham group (p ≤ 0.005). OVX reduced maximal running capacity by 17% (p = 0.005) with no changes in muscle mass or phosphorylated form of regulatory light chain (pRLC) in gastrocnemius muscle. OVX was associated with lower serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA) level in the NA compared with sham (p = 0.007). In response to acute exercise, OVX was associated with low serotonin level in the HC and high level in the NA (p ≤ 0.024). Discussion: Our results highlight that OVX reduces maximal running capacity and affects the response of brain neurochemical levels to acute exercise in a brain region-specific manner. These results may offer mechanistic insight into why OVX reduces willingness to exercise.

The effects of estrogens on spatial learning and memory in female rodents - A systematic review and meta-analysis.

Estrogens have inconsistent effects on learning and memory in both the clinical and preclinical literature. Preclinical literature has the advantage of investigating an array of potentially important factors contributing to the varied effects of estrogens on learning and memory, with stringently controlled studies. This study set out to identify specific factors in the animal literature that influence the effects of estrogens on cognition, for possible translation back to clinical practice. The literature was screened and studies meeting strict inclusion criteria were included in the analysis. Eligible studies included female ovariectomized rodents with an adequate vehicle for the estrogen treatment, with an outcome of spatial learning and memory in the Morris water maze. Training days of the Morris water maze were used to assess acquisition of spatial learning, and the probe trial was used to evaluate spatial memory recall. Continuous outcomes were pooled using a random effects inverse variance method and reported as standardized mean differences with 95 % confidence intervals. Subgroup analyses were developed a priori to assess important factors. The overall analysis favoured treatment for the later stages of training and for the probe trial. Factors including the type of estrogen, route, schedule of administration, age of animals, timing relative to ovariectomy, and duration of treatment were all found to be important. The subgroup analyses showed that chronic treatment with 17ß-estradiol, either cyclically or continuously, to young animals improved spatial recall. These results, observed in animals, can inform and guide further clinical research on hormone replacement therapy for cognitive benefits.

Ovariectomy in mouflons under field conditions: a comparative assessment of midventral and flank laparotomy approaches.

Ovariectomy is the best method to control the density of wild ungulate populations. The present study aimed to compare two surgical approaches of ovariectomy, via the flank and midventral, in mouflons under field conditions. A total of 20 female mouflons were enrolled in the study. The animals were divided randomly into two equal groups; group F animals were gonadectomized via the flank approach, while group L animals were sterilized via the linea alba access. The parameters evaluated were duration of surgery, duration of anesthesia, recovery time, intraoperative and postoperative complications, intraoperative nociception, and pain during the postoperative period. There were no intraoperative and postoperative complications. The evaluated parameters showed a very similar trend in both groups. Both techniques were found to be effective and safe in execution.

Impact of ovariectomy on neurotransmitter receptors BDNF/TrkB and endoplasmic reticulum molecular chaperones in rat hypoglossal nucleus.

Currently hypoglossal nerve-genioglossus axis is the major research core of OSA pathogenesis. The pathogenesis of OSA incidence changes before and after menopause needs to be clarified further. Little is known about the influences of ovariectomy on hypoglossal motoneurons. In the research, we utilized a rat ovariectomy model to evaluate the expression changes of 5-HT2A and α1-Adrenergic receptors in the hypoglossal nucleus and to explore the involvement of BDNF/TrkB signaling and endoplasmic reticulum molecular chaperones in the hypoglossal nucleus. Results indicated that the expression of 5-HT2A and α1-Adrenergic receptors reduced dramatically in the hypoglossal nucleus of ovariectomized rats. The apoptosis level of hypoglossal motor neurons increased markedly in the OVX groups. The up-regulated expression of BDNF and down-regulated expression of TrkB were found in the OVX groups. Ovarian insufficiency resulted in the activation of UPR and the loss of CANX-CALR cycle. Estrogen replacement could restore these changes partially. Estrogen level influences the expression of neurotransmitter receptors, and regulates BDNF/TrkB signaling compensation and endoplasmic reticulum homeostasis, which might be one of the pathogenesis of menopausal female OSA. The results reveal a new perspective for studying female OSA from the view of hypoglossal nerve and hormonal changes and attempt to propel 17ß-estradiol toward a feasible therapy for female OSA. Supplementary Information: The online version contains supplementary material available at 10.1007/s41105-024-00520-5.

Anti-osteoporotic effects of Boswellia serrata gum resin extract in vitro and in vivo.

BACKGROUND/OBJECTIVES: This study evaluated the beneficial effects of an ethanol extract of Boswellia serrata gum resin (FJH-UBS) in osteoporosis. MATERIALS/METHODS: MC3T3-E1 osteoblastic cells and RAW 264.7 osteoclastic cells were treated with FJH-UBS. The alkaline phosphatase (ALP) activity, mineralization, collagen synthesis, osteocalcin content, and Runt-related transcription factor 2 (RUNX2) and Osterix expression were measured in MC3T3-E1 cells. The actin ring structures, tartrate-resistant acid phosphatase (TRAP) activity, and the nuclear factor of activator T-cells, cytoplasm 1 (NFATc1) expression were evaluated in RAW 264.7 cells. Ovariectomized ICR mice were orally administered FJH-UBS for eight weeks. The bone mineral density (BMD) and the serum levels of osteocalcin, procollagen 1 N-terminal propeptide (P1NP), osteoprotegerin, and TRAP 5b were analyzed. RESULTS: FJH-UBS increased the ALP activity, collagen, osteocalcin, mineralization, and RUNX2 and osterix expression in MC3T3-E1 osteoblastic cells, whereas it decreased the TRAP activity, actin ring structures, and NFATc1 expression in RAW 264.7 osteoclastic cells. In ovariectomy-induced osteoporosis mice, FJH-UBS positively restored all of the changes in the bone metabolism biomarkers (BMD, osteocalcin, P1NP, osteoprotegerin, and TRAP 5b) caused by the ovariectomy. CONCLUSION: FJH-UBS has anti-osteoporotic activity by promoting osteoblast activity and inhibiting osteoclast activity in vitro and in vivo, suggesting that FJH-UBS is a potential functional food ingredient for osteoporosis.

Postoperative pain in dogs undergoing either laparoscopic or open ovariectomy.

A prospective, quasi-experimental, clinical trial was performed to assess acute postoperative pain in healthy female dogs following elective ovariectomy by either laparoscopy (n=13) or laparotomy (n=14). Pain was assessed by both a veterinarian at the hospital, and by the owner once the patient was discharged. The Spanish version of the short form of the Glasgow Composite Measuring Pain Scale (CMPS-SF) was used. Pain scores were assessed by the veterinarian preoperatively and at 1, 2, 4, and 6 h after extubation, whilst owner-assessed scores were performed preoperatively and at postoperative days 0, 1, 2, 3, 5 and 7. Data were compared with Mann-Whitney-U test. Veterinarian-assessed CMPS-SF scores were different between both groups at all postoperative times but not at baseline, being below 6/24 in all dogs in the laparoscopy group, but equal to or greater than 6/24 in the laparotomy group at 1 h (n=12), and 4 h (n=4) (P<0.001 and P=0.029, respectively). There were also differences in pain scores between both groups at 2 h (P=0.012) and 6 h (P=0.007), being below 6/24 in all of them. However, there were no differences in owner assessments between groups. In conclusion, ovariectomy performed by laparoscopy induced lower pain scores that were below the pain threshold set by the CMPS-SF during the first 6 h postoperatively. After discharge, and up to one week later, ongoing owner-assessed scores suggest no pain was induced with neither of the techniques. Owners were proactive allowing real-time pain assessment to be reported. The development and validation of instruments for acute pain assessment by owners is warranted, as these tools are currently lacking.

NOX4 and its association with myeloperoxidase and osteopontin in regulating endochondral ossification.

IMPORTANCE: Endochondral ossification plays an important role in skeletal development. Recent studies have suggested a link between increased intracellular reactive oxygen species (ROS) and skeletal disorders. Moreover, previous studies have revealed that increasing the levels of myeloperoxidase (MPO) and osteopontin (OPN) while inhibiting NADPH oxidase 4 (NOX4) can enhance bone growth. This investigation provides further evidence by showing a direct link between NOX4 and MPO, OPN in bone function. OBJECTIVE: This study investigates NOX4, an enzyme producing hydrogen peroxide, in endochondral ossification and bone remodeling. NOX4's role in osteoblast formation and osteogenic signaling pathways is explored. METHODS: Using NOX4-deficient (NOX4-/-) and ovariectomized (OVX) mice, we identify NOX4's potential mediators in bone maturation. RESULTS: NOX4-/- mice displayed significant differences in bone mass and structure. Compared to the normal Control and OVX groups. Hematoxylin and eosin staining showed NOX4-/- mice had the highest trabecular bone volume, while OVX had the lowest. Proteomic analysis revealed significantly elevated MPO and OPN levels in bone marrow-derived cells in NOX4-/- mice. Immunohistochemistry confirmed increased MPO, OPN, and collagen II (COLII) near the epiphyseal plate. Collagen and chondrogenesis analysis supported enhanced bone development in NOX4-/- mice. CONCLUSIONS AND RELEVANCE: Our results emphasize NOX4's significance in bone morphology, mesenchymal stem cell proteomics, immunohistochemistry, collagen levels, and chondrogenesis. NOX4 deficiency enhances bone development and endochondral ossification, potentially through increased MPO, OPN, and COLII expression. These findings suggest therapeutic implications for skeletal disorders.

Caffeine regulates both osteoclast and osteoblast differentiation via the AKT, NF-κB, and MAPK pathways.

Background: Although caffeine generally offers benefits to human health, its impact on bone metabolism remains unclear. Aim and Methods: This study aimed to systematically evaluate the long-term effects of caffeine administration on osteoclasts, osteoblasts, and ovariectomy-induced postmenopausal osteoporosis (OP). Results: Our in vitro findings revealed that 3.125 and 12.5 µg/mL caffeine inhibited RANKL-mediated osteoclastogenesis in RAW 264.7 cells through the MAPK and NF-κB pathways, accompanied by the inactivation of nuclear translocation of nuclear factor NFATc1. Similarly, 3.125 and 12.5 µg/mL of caffeine modulated MC3T3-E1 osteogenesis via the AKT, MAPK, and NF-κB pathways. However, 50 µg/mL of caffeine promoted the phosphorylation of IκBα, P65, JNK, P38, and AKT, followed by the activation of NFATc1 and the inactivation of Runx2 and Osterix, ultimately disrupting the balance between osteoblastogenesis and osteoclastogenesis. In vivo studies showed that gavage with 55.44 mg/kg caffeine inhibited osteoclastogenesis, promoted osteogenesis, and ameliorated bone loss in ovariectomized mice. Conclusion: Conversely, long-term intake of high-dose caffeine (110.88 mg/kg) disrupted osteogenesis activity and promoted osteoclastogenesis, thereby disturbing bone homeostasis. Collectively, these findings suggest that a moderate caffeine intake (approximately 400 mg in humans) can regulate bone homeostasis by influencing both osteoclasts and osteoblasts. However, long-term high-dose caffeine consumption (approximately 800 mg in humans) could have detrimental effects on the skeletal system.

The Effect of Ovariectomy and Estradiol Substitution on the Metabolic Parameters and Transcriptomic Profile of Adipose Tissue in a Prediabetic Model.

Menopause brings about profound physiological changes, including the acceleration of insulin resistance and other abnormalities, in which adipose tissue can play a significant role. This study analyzed the effect of ovariectomy and estradiol substitution on the metabolic parameters and transcriptomic profile of adipose tissue in prediabetic females of hereditary hypertriglyceridemic rats (HHTgs). The HHTgs underwent ovariectomy (OVX) or sham surgery (SHAM), and half of the OVX group received 17ß-estradiol (OVX+E2) post-surgery. Ovariectomy resulted in weight gain, an impaired glucose tolerance, ectopic triglyceride (TG) deposition, and insulin resistance exemplified by impaired glycogenesis and lipogenesis. Estradiol alleviated some of the disorders associated with ovariectomy; in particular, it improved insulin sensitivity and reduced TG deposition. A transcriptomic analysis of perimetrial adipose tissue revealed 809 differentially expressed transcripts in the OVX vs. SHAM groups, mostly pertaining to the regulation of lipid and glucose metabolism, and oxidative stress. Estradiol substitution affected 1049 transcripts with overrepresentation in the signaling pathways of lipid metabolism. The principal component and hierarchical clustering analyses of transcriptome shifts corroborated the metabolic data, showing a closer resemblance between the OVX+E2 and SHAM groups compared to the OVX group. Changes in the adipose tissue transcriptome may contribute to metabolic abnormalities accompanying ovariectomy-induced menopause in HHTg females. Estradiol substitution may partially mitigate some of these disorders.

Can a Sacrococcygeal Epidural of 0.25% Bupivacaine Prevent the Activation of the Sympathetic Nervous System during Feline Ovariectomy?

The ovariectomy (OVE) procedure can trigger somatosensory and visceral peritoneal nociception. Sacrococcygeal epidural (ScE) anesthesia may complement or replace systemic analgesia used for feline OVE, reducing opioid consumption and their related undesirable adverse effects and consequently reducing or completely blocking the sympathetic nervous system activation during this procedure. The present study aimed to evaluate the activation of the sympathetic nervous system resulting from adding an ScE injection of bupivacaine 0.25% (0.3 mL kg-1) in feline OVE and identify whether this translates to hemodynamic variables stability. A Parasympathetic Tone Activity (PTA) monitor was applied given that it performs analysis of heart rate variability (HRV) detecting changes in sympathetic and parasympathetic tone, making it a good tool for detecting activation of the sympathetic nervous system during the study. Two groups of animals were evaluated in five perioperative times, namely, the control group (CG) (n = 18) with systemic analgesia alone and the sacrococcygeal epidural group (ScEG) (n = 20) with 0.25% bupivacaine combined with systemic analgesia. Thirty-eight female cats were selected. All animals assigned to CG and ScEG were premedicated with dexmedetomidine (20 µg kg-1 IM) and methadone (0.2 mg kg-1 IM). General anesthesia was induced with propofol IV ad effectum and maintained with isoflurane in 100% oxygen. Heart rate, non-invasive systolic and median blood pressure, respiratory rate, and instantaneous parasympathetic tone activity were recorded. Compared to systemic analgesia alone (CG), sacrococcygeal epidural (ScEG) reduced the rise of common hemodynamic variables but did not prevent sympathetic nervous system activation.

Treatment with brain specific estrogen prodrug ameliorates cognitive effects of surgical menopause in mice.

Menopause is an endocrine shift leading to increased vulnerability for cognitive impairment and dementia risk factors, in part due to loss of neuroprotective circulating estrogens. Systemic replacement of estrogen post-menopause has limitations, including risk for estrogen-sensitive cancers. A promising therapeutic approach therefore might be to deliver estrogen only to the brain. We examined whether we could enhance cognitive performance by delivering estrogen exclusively to the brain in ovariectomized mice (a surgical menopause model). We treated mice with the prodrug 10ß,17ß-dihydroxyestra-1,4-dien-3-one (DHED), which can be administered systemically but is converted to 17ß-estradiol only in the brain. Young and middle-aged C57BL/6 J mice received ovariectomy and subcutaneous implant containing vehicle or DHED and underwent cognitive testing to assess memory after 1-3.5 months of treatment. Low and medium doses of DHED did not alter metabolic status in middle-aged mice. In both age groups, DHED treatment improved spatial memory in ovariectomized mice. Additional testing in middle-aged mice showed that DHED treatment improved working and recognition memory in ovariectomized mice. These results lay the foundation for future studies determining if this intervention is as efficacious in models of dementia with comorbid risk factors.

Estrogen deficiency affects synchronized neural connectivity in the olfactory bulb-nucleus accumbens circuit: A local field potential study in ovariectomized mouse model.

Estrogen plays a crucial role in regulating various brain functions, including cognitive, emotional, and social behaviors. Menopausal women face a decline in estrogen levels, which has been linked to several physical and mental health issues. However, the impact of estrogen on the olfactory bulb-nucleus accumbens (OB-NAc) circuit, which is essential for regulating emotions and cognitive behaviors, remains poorly understood. To test the hypothesis that estrogen deficiency affects signal processing, we recorded local field potentials (LFPs) using intracranial electrodes implanted in four-week-old ovariectomized (OVX) mice during an open-field test (OFT). The results showed a decrease in locomotor activity and increase in anxiety-like behaviors in OVX mice. Furthermore, we found a decrease in high-gamma power in the OB. We analyzed coherence and inter-region phase-amplitude coupling (ir-PAC) to explore the connectivity between the OB and NAc. We observed a decrease in low-gamma and high-gamma coherence in OVX mice. Additionally, we found that the direction of connectivity from the NAc to the OB was disrupted in OVX mice. In summary, our study provides evidence that estrogen deficiency is linked to synchronized neural connectivity changes in the OB-NAc circuit. These findings have implications for our understanding of the roles played by the OB-NAc neural circuit and estrogen in the regulation of general exploratory behavior and anxiety-like behavior.

Alleviation of Menopausal Symptoms by Yam (Dioscorea japonica Thunb.) and Gromwell (Lithospermum erythrorhizon Sieb. Et Zucc.) Extracts in Ovariectomized Mice.

SCOPE: The decline in estrogen during menopause contributes to a variety of menopausal symptoms, for which hormone replacement therapy (HRT) has been extensively applied. Regarding side effects and limited effectiveness of HRT for specific individuals, there is a growing interest in safe alternatives such as phytoestrogens which are structurally analogous to estrogens. This study aims to investigate the efficacy of yam and gromwell extracts, rich in bioactive compounds, and the synergistic effect of extracts on symptoms induced by estrogen deficiency in ovariectomized (OVX) mice. METHODS AND RESULTS: OVX mice receive dietary intervention of either yam, gromwell extract, or their mixture for 14 weeks. Sham-operated mice and E2-injected OVX mice serve as positive controls. Following 14 weeks of oral administration, blood, adipose tissue, vagina, uterus, femurs, and tibias are harvested for further investigation. Consequently, yam and gromwell extracts ameliorate menopausal conditions such as weight gain, glucose intolerance, dyslipidemia, and osteoporosis in estrogen-deficient OVX mice. In addition, the mixture of yam and gromwell extracts synergistically aids in the relief of the indications. CONCLUSION: These results indicate the potential use of yam and gromwell extracts, as well as their mixture, for the development of healthy functional foods to modulate menopausal symptoms.

Estrogen alleviates liver fibrosis and restores metabolic homeostasis in ovariectomy-induced liver injury and carbon tetrachloride (CCl4) exposure.

AIM: Given estrogen's recognized regulatory influence on diverse metabolic and immune functions, this study sought to explore its potential impact on fibrosis and elucidate the underlying metabolic regulations. METHODS: Female mice underwent ovary removal surgery, followed by carbon tetrachloride (CCl4) administration to induce liver injury. Biochemical index analysis and histopathological examination were then conducted. The expression levels of alpha-smooth muscle actin (α-SMA), transforming growth factor-ß (TGF-ß), and collagen type 1 alpha 1 chain (COL1A1) were assessed using western blotting to further elucidate the extent of liver injury. Finally, metabolite extraction and metabolomic analysis were performed to evaluate metabolic changes. RESULTS: Ovary removal exacerbated CCl4-induced liver damage, while estrogen supplementation provided protection against hepatic changes resulting from OVX. Furthermore, estrogen mitigated liver injury induced by CCl4 treatment in vivo. Estrogen supplementation significantly restored liver damage induced by OVX and CCl4. Comparative analysis revealed significant alterations in pathways including aminoacyl-tRNA biosynthesis, glycine, serine, and threonine metabolism, lysine degradation, and taurine and hypotaurine metabolism in estrogen treatment. CONCLUSION: Estrogen supplementation alleviates liver injury induced by OVX and CCl4, highlighting its protective effects against fibrosis and associated metabolic alterations.

A murine model of hypertensive heart disease in older women.

We propose a new mouse (C57Bl6/J) model combining several features of heart failure with preserved ejection fraction encountered in older women, including hypertension from Angiotensin II infusion (AngII), menopause, and advanced age. To mimic menopause, we delayed ovariectomy (Ovx) at 12 months of age. We also studied the effects of AngII infusion for 28 days in younger animals and the impact of losing gonadal steroids earlier in life. We observed that AngII effects on heart morphology were different in younger and adult mice (3- and 12-month-old; 20 and 19% increase in heart weight. P < 0.01 for both) than in older animals (24-month-old; 6%; not significant). Ovariectomy at 12 months restored the hypertrophic response to AngII in elderly females (23%, p = 0.0001). We performed a bulk RNA sequencing study of the left ventricle (LV) and left atrial gene expression in elderly animals, controls, and Ovx. AngII modulated (|Log2 fold change| ≥ 1) the LV expression of 170 genes in control females and 179 in Ovx ones, 64 being shared. In the left atrium, AngII modulated 235 genes in control females and 453 in Ovx, 140 shared. We observed many upregulated genes associated with the extracellular matrix regulation in both heart chambers. Many of these upregulated genes were shared between the ventricle and the atrium as well as in control and Ovx animals, namely for the most expressed Ankrd1, Nppb, Col3a1, Col1a1, Ctgf Col8a1, and Cilp. Several circadian clock LV genes were modulated differently by AngII between control and Ovx females (Clock, Arntl, Per2, Cry2, and Ciart). In conclusion, sex hormones, even in elderly female mice, modulate the heart's hypertrophic response to AngII. Our study identifies potential new markers of hypertensive disease in aging female mice and possible disturbances of their cardiac circadian clock.

Sinomenine increases osteogenesis in mice with ovariectomy-induced bone loss by modulating autophagy.

BACKGROUND: A decreased autophagic capacity of bone marrow mesenchymal stromal cells (BMSCs) has been suggested to be an important cause of decreased osteogenic differentiation. A pharmacological increase in autophagy of BMSCs is a potential therapeutic option to increase osteoblast viability and ameliorate osteoporosis. AIM: To explore the effects of sinomenine (SIN) on the osteogenic differentiation of BMSCs and the underlying mechanisms. METHODS: For in vitro experiments, BMSCs were extracted from sham-treated mice and ovariectomized mice, and the levels of autophagy markers and osteogenic differentiation were examined after treatment with the appropriate concentrations of SIN and the autophagy inhibitor 3-methyladenine. In vivo, the therapeutic effect of SIN was verified by establishing an ovariectomy-induced mouse model and by morphological and histological assays of the mouse femur. RESULTS: SIN reduced the levels of AKT and mammalian target of the rapamycin (mTOR) phosphorylation in the phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR signaling pathway, inhibited mTOR activity, and increased autophagy ability of BMSCs, thereby promoting the osteogenic differentiation of BMSCs and effectively alleviating bone loss in ovariectomized mice in vivo. CONCLUSION: The Chinese medicine SIN has potential for the treatment of various types of osteoporosis, bone homeostasis disorders, and autophagy-related diseases.

Ricinodendron heudelotii (Euphorbiaceae) seed oil prevents DMBA-induced breast cancer under menopause-like conditions in Wistar rats.

Despite efforts, breast cancer remains associated with a high incidence and mortality rate. Ricinodendron heudelotii also known as "Njansang," is a plant used for cancer treatment. While several reports on the anticancer potential of its leaves exist, little is known about its seed oil. This study aimed to evaluate the in vitro and in vivo anti-breast cancer activity of "Njansang" seed oil. The inhibitory effect of "Njansang" seed oil was determined using MTT and CCK-8 dye reduction assays. Breast cancer was induced with DMBA and promoted with E2V (1 mg/kg) for 4 weeks in ovariectomized rats (menopausal condition). Evaluated parameters included tumor incidence, tumor mass and volume, histopathology, breast cancer biomarker CA 15-3, antioxidant status (CAT, GSH, MDA, NO, SOD), TNF-α and INFγ levels, lipid profile (total cholesterol, LDL-cholesterol, triglycerides and HDL-cholesterol), as well as toxicity parameters (ALT, AST, creatinine). "Njansang" oil significantly reduced the growth of ER+ (MCF-7) and triple negative (MDA-MB 231) adenocarcinoma cells in vitro as well as tumor incidence, tumor mass and CA 15-3 levels in vivo. It exhibited antioxidant activity, characterized by an increase in SOD and catalase activities, GSH levels and decreased MDA levels compared to the DMBA group. TNF-α and INF-γ levels were reduced following oil treatment, while total cholesterol, LDL-cholesterol and triglyceride levels were reduced. The aforementioned findings confirm the protective effects of "Njansang" oil on induced breast cancer in ovariectomized rats.

The lack of EphB3 receptor prevents bone loss in mouse models of osteoporosis.

Bone homeostasis is a complex process in which some Eph kinase receptors and their ephrin ligands appear to be involved. In the present study we address this issue by examining, both in vitro and in vivo, the role of EphB2 and EphB3 in MSC differentiation into bone tissue. This was firstly evaluated by RT-qPCR and histological staining in MSCs cultured in specific mediums revealing that, whereas EphB2-/- MSCs mainly expressed pro-adipogenic transcription factors, EphB3-/- MSCs showed abundant osteogenic transcripts, such as Runx2, Msx2 and Sp7. To clarify the underlying molecular mechanisms, we found that the lack of EphB3 signaling alters the genetic profile of differentiating MSCs, reducing the expression of many inhibitory molecules and antagonists of the BMP signaling pathway, and increasing Bmp7 expression, a robust bone inductor. Then, to confirm the osteogenic role of EphB3 in vivo, we studied the condition of two mouse models of induced bone loss (ovariectomy or long-term glucocorticoid treatment). Interestingly, in both models, both WT and EphB2-/- mice equally developed the disease but EphB3-/- mice did not exhibit the typical bone loss, nor an increase in urine Ca2+ or blood serum CTX-1. This phenotype in EphB3-KO mice could be due to their significantly higher proportions of osteoprogenitor cells and preosteoblasts, and their lower number of osteoclasts, as compared with WT and EphB2-KO mice. Thus, we conclude that EphB3 acts as a negative regulator of the osteogenic differentiation, and its absence prevents bone loss in mice subjected to ovariectomy or dexamethasone treatment.

Osteoporosis affects more than 200 million people, mostly women. Our work shows that the EphB3 receptor restricts bone formation, and its absence prevents bone loss in osteoporotic mice. The bone protection observed in EphB3-deficient mice is due to the presence of more bone-forming cells and fewer bone-degrading cells. Molecularly, we found that when there's no EphB3 in mesenchymal stem cells, some bone-promoting genes are increased while many inhibitors are reduced. Therefore, this receptor could become a key target for new therapies that would help to improve the quality of life for those suffering from bone diseases. We're really excited to share our findings with a broad audience, including patients, healthcare professionals, researchers, and the life sciences industry.