Search results for "Ovariectomized rat"
showing 10 items of 24 documents
Decreased bioavailability of nitric oxide in aorta from ovariectomized senescent mice. Role of cyclooxygenase.
2015
This study investigates the effects of aging and/or ovariectomy on vascular reactivity to thromboxane A2 (TXA2) receptor stimulation with U46619, and the modulation by nitric oxide (NO) and cyclooxygenase (COX) in aorta from female senescence-accelerated mice (SAMP8) and from senescence resistant mice (SAMR1). Five-month-old female SAMR1 and SAMP8 were divided into three groups: sham-operated, ovariectomized and ovariectomized plus estradiol. Twenty-eight days after surgery, thoracic aortic rings were mounted for isometric recording of tension and concentration-response curves for U46619 (10(-10)-3 × 10(-7) M) were performed in the absence and in the presence of the NO synthase inhibitor N(…
Low-energy extracorporeal shockwave therapy (ESWT) improves metaphyseal fracture healing in an osteoporotic rat model.
2017
Purpose As result of the current demographic changes, osteoporosis and osteoporotic fractures are becoming an increasing social and economic burden. In this experimental study, extracorporeal shock wave therapy (ESWT), was evaluated as a treatment option for the improvement of osteoporotic fracture healing. Methods A well-established fracture model in the metaphyseal tibia in the osteoporotic rat was used. 132 animals were divided into 11 groups, with 12 animals each, consisting of one sham-operated group and 10 ovariectomized (osteoporotic) groups, of which 9 received ESWT treatment. Different energy flux intensities (0.15 mJ/mm2, 0.35 mJ/mm2, or 0.55 mJ/mm2) as well as different numbers o…
Long-term vitamin D treatment decreases human uterine leiomyoma size in a xenograft animal model
2019
Objective To study the effects of short- and long-term vitamin D treatment on uterine leiomyomas in vivo through cell proliferation, extracellular matrix (ECM) degradation, and apoptosis. Design Preclinical study of human leiomyoma treatment with vitamin D in an nonhuman animal model. Setting Hospital and university laboratories. Patient(s)/Animal(s) Human leiomyomas were collected from patients and implanted in ovariectomized NOD-SCID mice. Intervention(s) Mice were treated with vitamin D (0.5 μg/kg/d or 1 μg/kg/d) or vehicle for 21 or 60 days. Main Outcome Measure(s) Vitamin D effect in xenograft tissue was assessed by monitoring tumor size (18F-FDG positron-emission tomography/computeriz…
Can a healthy life prevent us from post-menopausal osteoporosis? Myths and truths
2016
Abstract Postmenopausal osteoporosis is related to unmodifiable risk factors (genetics, race, gender and age). However, other controllable factors such as activity, body mass, hormone and calcium levels and dietary habits can reduce fracture risk. For example, significant increases in bone mass density have been linked to physical activity in children, supplements of Vitamin C taken for more than 10 years, or high consumption of fish, olive oil or dried plums. This review establishes the scientific basis behind these non-pharmaceutical practices and summarizes a number of basic studies and clinical trials involving them as well as discusses their potential for the osteoporosis treatment. A …
Menopause and ovariectomy cause a low grade of systemic inflammation that may be prevented by chronic treatment with low doses of estrogen or losarta…
2009
Abstract The incidence of cardiovascular diseases in premenopausal women is lower than in men or postmenopausal women. This study reports the discovery of a low grade of systemic inflammation, including monocyte adhesion to arterial endothelium, elicited by menopause or estrogen depletion. Chronic treatment with low dose of 17-β-estradiol or inhibition of the renin-angiotensin system reduced this inflammation. Using an in vitro flow chamber system with human arterial and venous endothelial cells, we found that leukocytes from healthy postmenopausal women were more adhesive to the arterial endothelium than those from premenopausal women regardless of the stimulus used on endothelial cells. I…
Effects of Nrf2 deficiency on bone microarchitecture in an experimental model of osteoporosis
2014
Objective. Redox imbalance contributes to bone fragility. We have evaluated the in vivo role of nuclear factor erythroid derived 2-related factor-2 (Nrf2), an important regulator of cellular responses to oxidative stress, in bone metabolism using a model of postmenopausal osteoporosis. Methods. Ovariectomy was performed in both wild-type and mice deficient in Nrf2 (Nrf2-/-). Bone microarchitecture was analyzed by CT. Serum markers of bone metabolism were also measured. Reactive oxygen species production was determined using dihydrorhodamine 123. Results. Sham-operated or ovariectomized Nrf2 -/- mice exhibit a loss in trabecular bone mineral density in femur, accompanied by a reduction in co…
Effects of locally applied Insulin-like Growth Factor-I on osseointegration.
2019
Background The aim of this study was to assess the effect of local application of IGF-I on osseointegration of dental implants placed in osteoporotic bones. Material and Methods 16 rabbits were randomly distributed into two groups: eight animals were ovariectomized and fed a low-calcium diet for six weeks, in order to induce experimental osteoporosis, and the others were sham-operated and fed a standard diet. A titanium implant was inserted into the tibiae in both groups. In half of the rabbits, 4 μg of IGF-I was applied into the ostectomy, prior to the implant insertion. A total of 32 implants were placed. Animals were sacrificed two weeks after surgery and decalcified samples were process…
Gene expression profile induced by ovariectomy in bone marrow of mice: a functional approach to identify new candidate genes associated to osteoporos…
2013
Osteoporosis is a multifactorial skeletal pathology with a main genetic component. To date, however, the majority of genes associated with this pathology remain unknown since genes cataloged to date only explain a part of the heritability of bone phenotypes. In the present study, we have used a genome-wide gene expression approach by means of microarrays to identify new candidate genes involved in the physiopathology of osteoporosis, using as a model the ovariectomized (OVX) mice by comparing global bone marrow gene expression of the OVX mice with those of SHAM operated mice. One hundred and eighty transcripts were found to be differentially expressed between groups. The analysis showed 23 …
Estrogenic effects of food wrap packaging xenoestrogens and flavonoids in female Wistar rats : a comparative study
2003
International audience; The objective of this study was to compare the estrogenicity of xenoestrogens found in food wrap packaging and phytoestrogen flavonoids. Uterotrophic and vaginal cornification assays were performed on immature and ovariectomized rats. Genistein, bisphenol F, and octylphenol were identified as estrogenic only in immature rats. Using vaginal cornification as a more specific estrogenic parameter, all tested compounds except tangeretin were active in immature rats. While apigenin and kaempferol appeared to have low estrogenic activity, they potentialized the uterotrophic effect of 17β-estradiol in immature rats. These data showed that (i) phytoestrogens like genistein ca…
Sex Differences in Age-Associated Type 2 Diabetes in Rats—Role of Estrogens and Oxidative Stress
2019
Females live longer than males, and the estrogens are one of the reasons for this difference. We reported some years ago that estrogens are able to protect rats against oxidative stress, by inducing antioxidant genes. Type 2 diabetes is an age-associated disease in which oxidative stress is involved, and moreover, some studies show that the prevalence is higher in men than in women, and therefore there are sex-associated differences. Thus, the aim of this study was to evaluate the role of estrogens in protecting against oxidative stress in type 2 diabetic males and females. For this purpose, we used Goto-Kakizaki rats, which develop type 2 diabetes with age. We found that female diabetic ra…