Intrastriatal injection (16microg) of the neurotoxic dopaminergic agent 6-hydroxydopamine (6-OHDA) in ovariectomized rats caused important reductions in striatal dopamine (DA) and serotonin (5-HT) levels and an increase in GABA content. Treatment of ovariectomized rats with estradiol (5 mg 17-beta-estradiol administered by a subcutaneous cannula) before 6-OHDA injection maintained the control levels of these neurotransmitters. The administration of estradiol after 6-OHDA injection did not lead to their recovery. These findings suggest that estradiol acts as a neuroprotectant--but not as a neuroreparatory agent--and that it might be able to attenuate striatal dopaminergic neuron degeneration caused by neurotoxic agents.
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http://dx.doi.org/10.1016/j.tox.2004.06.021 | DOI Listing |
J Reprod Dev
January 2025
Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan.
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View Article and Find Full Text PDFBiol Pharm Bull
January 2025
Division of Bio-Analytical Chemistry, Faculty of Medical Technology, Niigata University of Pharmacy and Medical and Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata 956-8603, Japan.
Postmenopausal women are at a higher risk of developing dyslipidemia and osteoporosis due to estrogen deficiency, necessitating regular vitamin D supplementation and the use of cholesterol inhibitors, respectively, to prevent these conditions. Despite current treatments, alternatives are needed to address both conditions simultaneously. Ergosterol, a precursor of vitamin D, is a fungal sterol converted to brassicasterol by 7-dehydrocholesterol reductase, a cholesterol biosynthesis enzyme that converts 7-dehydrocholesterol (a precursor of vitamin D) into cholesterol.
View Article and Find Full Text PDFHorm Behav
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Department of Psychology, University of Houston, Houston, TX 77204-5022, United States; Houston Methodist Research Institute, Houston, TX 77030, United States.
The benefits of estrogen treatment on cognition in middle-aged and older women are dependent on many factors, including the timing of treatment. Moreover, the potential interactive effects with other lifestyle factors, such as exercise, are poorly understood. In this study, we tested for lasting benefits of independent and combined treatment with estrogen and voluntary exercise initiated in midlife, using a rat model of menopause.
View Article and Find Full Text PDFChin J Nat Med
January 2025
The First Clinical Academy, Guangzhou University of Chinese Medicine, Guangzhou 510405, China; The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510407, China; Lingnan Medical Research Center of Guangzhou University of Chinese Medicine, Guangzhou 510405, China. Electronic address:
Osteoporosis is a prevalent skeletal condition characterized by reduced bone mass and strength, leading to increased fragility. Buqi-Tongluo (BQTL) decoction, a traditional Chinese medicine (TCM) prescription, has yet to be fully evaluated for its potential in treating bone diseases such as osteoporosis. To investigate the mechanism by which BQTL decoction inhibits osteoclast differentiation in vitro and validate these findings through in vivo experiments.
View Article and Find Full Text PDFBiochem Biophys Res Commun
January 2025
Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, Shenzhen-Hong Kong Institute of Brain Science, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China; CAS Key Laboratory of Brain Connectome and Manipulation, The Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China; University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address:
Parathyroid hormone (PTH) is critical for regulating calcium and phosphate homeostasis, and its dysregulation contributes to osteoporosis. Current methods for precise control of PTH secretion are limited. This study explores chemogenetic tools to regulate PTH secretion in parathyroid chief cells via Gq/Gi signaling.
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