1
|
Birkhaeuser M, Bitzer J, Braat S, Ramos Y. Esmirtazapine treatment of postmenopausal vasomotor symptoms: two randomized controlled trials. Climacteric 2019; 22:312-322. [DOI: 10.1080/13697137.2018.1561664] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- M. Birkhaeuser
- Division of Gynaecological Endocrinology and Reproductive Medicine, Department of Obstetrics & Gynaecology, University of Bern, Bern, Switzerland
| | - J. Bitzer
- Department of Obstetrics and Gynecology, University Hospital, Basel, Switzerland
| | - S. Braat
- MSD, Oss, The Netherlands
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - Y. Ramos
- MSD, Munich, Germany
- Ramos Pharma Consulting, Munich, Germany
- Formerly Organon GmbH, Oberschleissheim, Germany
| |
Collapse
|
2
|
Xu Y, Li X, Chen T, Qu Y, Zheng H, Zhang Z, Zhao Y, Lin N. Retracted
: Radix Paeoniae Alba increases serum estrogen level and up‐regulates estrogen receptor expression in uterus and vagina of immature/ovariectomized mice. Phytother Res 2018; 33:117-129. [DOI: 10.1002/ptr.6205] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 09/05/2018] [Accepted: 09/08/2018] [Indexed: 11/07/2022]
Affiliation(s)
- Ying Xu
- Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing China
| | - Xin Li
- Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing China
| | - Ting Chen
- Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing China
| | - Ya‐kun Qu
- Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing China
| | - Hong‐xia Zheng
- Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing China
| | - Zi‐jia Zhang
- Institute of Chinese Materia Medica Shanghai University of Traditional Chinese Medicine Shanghai China
| | - Yuan Zhao
- Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing China
| | - Na Lin
- Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing China
| |
Collapse
|
3
|
Meléndez-Gallardo J, Eblen-Zajjur A. Thermo-dependence of noxious mechanical heterotopic stimulation-dependent modulation of the spinal dorsal horn response to somatosensory stimulation. J Integr Neurosci 2018; 17:413-424. [PMID: 29562550 DOI: 10.3233/jin-180076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Despite the frequent clinical hyper- or hypothermia cases, thermal-dependence of the endogenous pain modulation system at the spinal cord is not well understood. We evaluate spinal dorsal horn neuronal network responses during mechanical heterotopic noxious stimuli (HNS) at three different body temperatures (34; 37 or 40°C) by measuring lumbar cord dorsum potentials activated by electrical stimulation of the ipsilateral sural nerve in adult thiopental anesthetized rats. A noxious clamp was applied randomly to the tail, right hindpaw, right forepaw, muzzle and left forepaw. HNS induced a decrease of the N wave amplitude and duration at 37°C. This effect was reduced at 40°C for both amplitude (-18.2% for 37-40°C; P<0.0005) and duration (-16.4% for 37-40°C; P<0.0001). P wave did not show neither amplitude nor duration changes at neither 3 tested temperatures. Clinical range changes of temperature could modify pain sensation, moreover, hyperthermia increases nociceptive sensory input to dorsal horn, and could exacerbate pain sensation in individuals with fever.
Collapse
Affiliation(s)
- J Meléndez-Gallardo
- Centro de Biofísica y Bioquímica del Instituto Venezolano de Investigaciones Científicas, IVIC, Caracas, Venezuela.,Centro de Biofísica y Neurociencias, CBN-UC, Facultad de Ciencias de la Salud, Universidad de Carabobo, Valencia, Venezuela
| | - A Eblen-Zajjur
- Centro de Biofísica y Neurociencias, CBN-UC, Facultad de Ciencias de la Salud, Universidad de Carabobo, Valencia, Venezuela.,Instituto de Ingeniería Biológica y Médica, Facultades de Ingeniería, Medicina y Biología, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, P.O. 7820436, Santiago de Chile, Chile
| |
Collapse
|
4
|
Krajewski-Hall SJ, Blackmore EM, McMinn JR, Rance NE. Estradiol alters body temperature regulation in the female mouse. Temperature (Austin) 2017; 5:56-69. [PMID: 29687044 DOI: 10.1080/23328940.2017.1384090] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Revised: 09/18/2017] [Accepted: 09/18/2017] [Indexed: 10/18/2022] Open
Abstract
Hot flushes are due to estrogen withdrawal and characterized by the episodic activation of heat dissipation effectors. Recent studies (in humans and rats) have implicated neurokinin 3 (NK3) receptor signaling in the genesis of hot flushes. Although transgenic mice are increasingly used for biomedical research, there is limited information on how 17β-estradiol and NK3 receptor signaling alters thermoregulation in the mouse. In this study, a method was developed to measure tail skin temperature (TSKIN) using a small data-logger attached to the surface of the tail, which, when combined with a telemetry probe for core temperature (TCORE), allowed us to monitor thermoregulation in freely-moving mice over long durations. We report that estradiol treatment of ovariectomized mice reduced TCORE during the light phase (but not the dark phase) while having no effect on TSKIN or activity. Estradiol also lowered TCORE in mice exposed to ambient temperatures ranging from 20 to 36°C. Unlike previous studies in the rat, estradiol treatment of ovariectomized mice did not reduce TSKIN during the dark phase. Subcutaneous injections of an NK3 receptor agonist (senktide) in ovariectomized mice caused an acute increase in TSKIN and a reduction in TCORE, consistent with the activation of heat dissipation effectors. These changes were reduced by estradiol, suggesting that estradiol lowers the sensitivity of central thermoregulatory pathways to NK3 receptor activation. Overall, we show that estradiol treatment of ovariectomized mice decreases TCORE during the light phase, reduces the thermoregulatory effects of senktide and modulates thermoregulation differently than previously described in the rat.
Collapse
Affiliation(s)
- Sally J Krajewski-Hall
- Departments of Pathology (S.J.K-H., E.M.B., J.R.M. and N.E.R.), Cellular and Molecular Medicine (N.E.R.), Neurology (N.E.R.) and the Evelyn F. McKnight Brain Institute (N.E.R.) University of Arizona College of Medicine, Tucson, AZ, USA
| | - Elise M Blackmore
- Departments of Pathology (S.J.K-H., E.M.B., J.R.M. and N.E.R.), Cellular and Molecular Medicine (N.E.R.), Neurology (N.E.R.) and the Evelyn F. McKnight Brain Institute (N.E.R.) University of Arizona College of Medicine, Tucson, AZ, USA
| | - Jessi R McMinn
- Departments of Pathology (S.J.K-H., E.M.B., J.R.M. and N.E.R.), Cellular and Molecular Medicine (N.E.R.), Neurology (N.E.R.) and the Evelyn F. McKnight Brain Institute (N.E.R.) University of Arizona College of Medicine, Tucson, AZ, USA
| | - Naomi E Rance
- Departments of Pathology (S.J.K-H., E.M.B., J.R.M. and N.E.R.), Cellular and Molecular Medicine (N.E.R.), Neurology (N.E.R.) and the Evelyn F. McKnight Brain Institute (N.E.R.) University of Arizona College of Medicine, Tucson, AZ, USA
| |
Collapse
|
5
|
El-Tanbouly DM, Wadie W, Sayed RH. Modulation of TGF-β/Smad and ERK signaling pathways mediates the anti-fibrotic effect of mirtazapine in mice. Toxicol Appl Pharmacol 2017. [DOI: 10.1016/j.taap.2017.06.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
6
|
Marques DA, de Carvalho D, da Silva GSF, Szawka RE, Anselmo-Franci JA, Bícego KC, Gargaglioni LH. Influence of estrous cycle hormonal fluctuations and gonadal hormones on the ventilatory response to hypoxia in female rats. Pflugers Arch 2017; 469:1277-1286. [PMID: 28660294 DOI: 10.1007/s00424-017-2022-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 06/18/2017] [Accepted: 06/19/2017] [Indexed: 12/12/2022]
Abstract
Sex hormones may influence many physiological processes. Recently, we demonstrated that hormonal fluctuations of cycling female rats do not affect respiratory parameters during hypercapnia. However, it is still unclear whether sex hormones and hormonal fluctuations that occur during the estrous cycle can affect breathing during a hypoxic challenge. Our study aimed to evaluate respiratory, metabolic, and thermal responses to hypoxia in female rats on different days of the estrous cycle (proestrus, estrus, metestrus, and diestrus) and in ovariectomized rats that received replacement with oil (OVX), estradiol (OVX + E2), or a combination of estradiol and progesterone (OVX + E2P). Ventilation (V E), tidal volume (V T), respiratory frequency (fR), oxygen consumption (VO2), and V E/VO2 were not different during the estrous cycle in normoxia or hypoxia. Body temperature (Tb) was higher during estrus, but decreased similarly in all groups during hypoxia. Compared with intact females in estrus, gonadectomized rats also had lower Tb in normoxia, but not in hypoxia. OVX rats experienced a significant drop in the ventilatory response to hypoxia, but hormonal replacement did not restore values to the levels of an intact animal. Our data demonstrate that the different phases of the estrous cycle do not alter ventilation during normoxia and hypoxia, but OVX animals display lower ventilatory responses to hypoxia compared with ovary-intact rats. Because estradiol and progesterone replacement did not cause significant differences in ventilation, our findings suggest that a yet-to-be-defined non-steroidal ovarian hormone is likely to stimulate the ventilatory responses to hypoxia in females.
Collapse
Affiliation(s)
- Danuzia A Marques
- Department of Animal Morphology and Physiology, São Paulo State University, UNESP FCAV at Jaboticabal, São Paulo, Brazil
| | | | - Glauber S F da Silva
- Department of Animal Morphology and Physiology, São Paulo State University, UNESP FCAV at Jaboticabal, São Paulo, Brazil
| | - Raphael E Szawka
- Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Minas Gerais, Brazil
| | - Janete A Anselmo-Franci
- Department of Morphology, Stomatology and Physiology, Dental School of Ribeirao Preto, University of São Paulo, São Paulo, Brazil
| | - Kênia C Bícego
- Department of Animal Morphology and Physiology, São Paulo State University, UNESP FCAV at Jaboticabal, São Paulo, Brazil
| | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, São Paulo State University, UNESP FCAV at Jaboticabal, São Paulo, Brazil.
| |
Collapse
|
7
|
Wuttke W, Seidlová-Wuttke D. Black cohosh (Cimicifuga racemosa) is a non-estrogenic alternative to hormone replacement therapy. CLINICAL PHYTOSCIENCE 2015. [DOI: 10.1186/s40816-015-0013-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|
8
|
Montrezor LH, de Carvalho D, Dias MB, Anselmo-Franci JA, Bícego KC, Gargaglioni LH. Hypoxic and hypercapnic ventilatory responses in rats with polycystic ovaries. Respir Physiol Neurobiol 2015; 217:17-24. [DOI: 10.1016/j.resp.2015.06.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 06/20/2015] [Accepted: 06/21/2015] [Indexed: 01/11/2023]
|
9
|
Xu Y, Ma XP, Ding J, Liu ZL, Song ZQ, Liu HN, Lin N. Treatment with qibaomeiran, a kidney-invigorating Chinese herbal formula, antagonizes estrogen decline in ovariectomized rats. Rejuvenation Res 2015; 17:372-81. [PMID: 24773352 DOI: 10.1089/rej.2014.1557] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Traditional Chinese medicines (TCM) contain multi-interactive compounds that have been used for treatment of peri-menopausal syndrome and have become a new phytoestrogens resource. The QiBaoMeiRan formula (QBMR), including Polygoni multiflori radix, Angelicae sinensis radix, Achyranthis bidentatae radix, semen Cuscutae, fructus Lycii, Poria, and fructus Psoraleae, has been used clinically for treating osteoporosis in post-menopausal women by virtue of its kidney-invigorating function. However, no evidence base links QBMR to estrogen replacement therapy. In this study, we undertook a characterization of estrogenic activity of QBMR using ovariectomized (OVX) rats. OVX rats were treated with QBMR at doses of 0.875, 1.75, and 3.5 grams/kg per day for 8 weeks. QBMR treatments demonstrated significant estrogenic activity, as indicated by vaginal cornification, reversal of atrophy of uterus, vagina, and mammary gland, and up-regulation of estrogen receptor α (ERα) and estrogen receptor β (ERβ) expression in the reproductive target tissues, where ERβ up-regulation was stronger than that of ERα. Meanwhile, treatment with QBMR significantly increased adrenal weight and serum estradiol levels and tended to decrease serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels in a dose-dependent manner. Moreover, QBMR significantly decreased weight gain and rectal temperature increase caused by ovariectomy, and the largest changes in rectal temperature were found at the lowest dose. The data suggest that QBMR's estrogenic responses show tissue variation that reflects different affinities of ERs for QBMR components. This study demonstrates that QBMR activity is mediated through estrogenic components and provides an evidence base for QBMR treatment of post-menopausal symptoms.
Collapse
Affiliation(s)
- Ying Xu
- 1 Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences , Beijing, China
| | | | | | | | | | | | | |
Collapse
|
10
|
Wuttke W, Jarry H, Haunschild J, Stecher G, Schuh M, Seidlova-Wuttke D. The non-estrogenic alternative for the treatment of climacteric complaints: Black cohosh (Cimicifuga or Actaea racemosa). J Steroid Biochem Mol Biol 2014; 139:302-10. [PMID: 23459142 DOI: 10.1016/j.jsbmb.2013.02.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Revised: 02/05/2013] [Accepted: 02/18/2013] [Indexed: 01/19/2023]
Abstract
In postmenopausal women estrogens in combination with progestins have beneficial effects on climacteric complaints and on osteoporosis but this hormone replacement therapy (HRT) bears the risk of increased mammary carcinomas and cardiovascular diseases. Phytoestrogens at low doses have little or no effects on climacteric complaints, at high doses they mimic the effects of estrogens. Therefore other plant derived substances are currently intensively investigated. Extracts of the rhizome of black cohosh (Cimicifuga racemosa=CR) did not bind to estrogen receptors and were shown to be devoid of estrogenic effects on mammary cancer cells in vitro and on mammary gland and uterine histology in ovariectomized rats. In addition in this rat model the special extract CR BNO 1055 inhibited the occurrence of hot flushes and development of osteoporosis. In postmenopausal women CR BNO 1055 reduced major climacteric complaints as effectively as conjugated estrogens and significantly more than placebo. Similar data were published for other European CR preparations whereas 2 US American preparations were ineffective. This was most likely due to the too high doses or due to the adulteration with Asian Cimicifuga preparations. In all European studies neither effects in the uterus nor in mammary glands were observed. The effective compounds in CR are most likely neurotransmitter-mimetic in nature: dopaminergic, noradrenergic, serotoninergic and GABAergic effects were demonstrated and some have been structurally identified. We conclude that CR extracts at low doses are effective to ameliorate climacteric complaints but are devoid of adverse estrogenic effects. These finding strengthens the role of CR extracts as substitutes for HRT. This article is part of a special issue entitled: Special Issue on Phytoestrogens.
Collapse
Affiliation(s)
- Wolfgang Wuttke
- Hormone and Obesity Center Goettingen, Bahnhofsallee 1d, 37081 Göttingen, Germany.
| | | | | | | | | | | |
Collapse
|
11
|
Rance NE, Dacks PA, Mittelman-Smith MA, Romanovsky AA, Krajewski-Hall SJ. Modulation of body temperature and LH secretion by hypothalamic KNDy (kisspeptin, neurokinin B and dynorphin) neurons: a novel hypothesis on the mechanism of hot flushes. Front Neuroendocrinol 2013; 34:211-27. [PMID: 23872331 PMCID: PMC3833827 DOI: 10.1016/j.yfrne.2013.07.003] [Citation(s) in RCA: 201] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 07/09/2013] [Accepted: 07/12/2013] [Indexed: 12/31/2022]
Abstract
Despite affecting millions of individuals, the etiology of hot flushes remains unknown. Here we review the physiology of hot flushes, CNS pathways regulating heat-dissipation effectors, and effects of estrogen on thermoregulation in animal models. Based on the marked changes in hypothalamic kisspeptin, neurokinin B and dynorphin (KNDy) neurons in postmenopausal women, we hypothesize that KNDy neurons play a role in the mechanism of flushes. In the rat, KNDy neurons project to preoptic thermoregulatory areas that express the neurokinin 3 receptor (NK3R), the primary receptor for NKB. Furthermore, activation of NK₃R in the median preoptic nucleus, part of the heat-defense pathway, reduces body temperature. Finally, ablation of KNDy neurons reduces cutaneous vasodilatation and partially blocks the effects of estrogen on thermoregulation. These data suggest that arcuate KNDy neurons relay estrogen signals to preoptic structures regulating heat-dissipation effectors, supporting the hypothesis that KNDy neurons participate in the generation of flushes.
Collapse
Affiliation(s)
- Naomi E Rance
- Department of Pathology and the Evelyn F. McKnight Brain Research Institute, University of Arizona College of Medicine, Tucson, AZ 85724, USA.
| | | | | | | | | |
Collapse
|
12
|
Endpoints of drug discovery for menopausal vasomotor symptoms: interpretation of data from a proxy of disease. Menopause 2012; 19:909-15. [PMID: 22473248 DOI: 10.1097/gme.0b013e318245533f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Estrogen supplementation is considered a reliable therapeutic approach to symptoms of vasomotor dysregulation (hot flashes) associated with the menopausal transition and sex hormone deprivation. Implication of changes in central neurotransmission in the pathogenesis of hot flashes has prompted the off-label use of serotonergic and γ-aminobutyric acid-ergic drugs as a therapeutic alternative, claiming similarity of outcomes to those of estrogen treatment. METHODS Using telemetric recordings in a rat model of estrogen deficit-induced vasomotor dysregulation, we compared the long- and short-term effects of estrogen supplementation and treatment with neuropharmaceuticals (venlafaxine, desvenlafaxine, fluoxetine, agomelatine, gabapentin) on endpoints of thermoregulation. RESULTS Among the tested drugs, only fluoxetine was capable to emulate the restorative action of estradiol on the diurnal oscillations in skin temperature and control of heat dissipation. Unlike estradiol, several of the tested compounds produced marked transient decreases in skin temperature within the first 2 hours of application while being unable to restore physiological diurnal patterns of thermoregulation. CONCLUSIONS Our findings suggest that in this animal model of impaired thermoregulation, neuropharmaceuticals may simulate therapeutic effects by eliciting immediate but transient hypothermia, which is not associated with the recovery of physiological control of heat dissipation. Therefore, short-term monitoring of drug actions in this disease model may considerably bias readouts of drug discovery for menopausal vasomotor symptoms.
Collapse
|
13
|
Role for kisspeptin/neurokinin B/dynorphin (KNDy) neurons in cutaneous vasodilatation and the estrogen modulation of body temperature. Proc Natl Acad Sci U S A 2012; 109:19846-51. [PMID: 23150555 DOI: 10.1073/pnas.1211517109] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Estrogen withdrawal in menopausal women leads to hot flushes, a syndrome characterized by the episodic activation of heat dissipation effectors. Despite the extraordinary number of individuals affected, the etiology of flushes remains an enigma. Because menopause is accompanied by marked alterations in hypothalamic kisspeptin/neurokinin B/dynorphin (KNDy) neurons, we hypothesized that these neurons could contribute to the generation of flushes. To determine if KNDy neurons participate in the regulation of body temperature, we evaluated the thermoregulatory effects of ablating KNDy neurons by injecting a selective toxin for neurokinin-3 expressing neurons [NK(3)-saporin (SAP)] into the rat arcuate nucleus. Remarkably, KNDy neuron ablation consistently reduced tail-skin temperature (T(SKIN)), indicating that KNDy neurons facilitate cutaneous vasodilatation, an important heat dissipation effector. Moreover, KNDy ablation blocked the reduction of T(SKIN) by 17β-estradiol (E(2)), which occurred in the environmental chamber during the light phase, but did not affect the E(2) suppression of T(SKIN) during the dark phase. At the high ambient temperature of 33 °C, the average core temperature (T(CORE)) of ovariectomized (OVX) control rats was significantly elevated, and this value was reduced by E(2) replacement. In contrast, the average T(CORE) of OVX, KNDy-ablated rats was lower than OVX control rats at 33 °C, and not altered by E(2) replacement. These data provide unique evidence that KNDy neurons promote cutaneous vasodilatation and participate in the E(2) modulation of body temperature. Because cutaneous vasodilatation is a cardinal sign of a hot flush, these results support the hypothesis that KNDy neurons could play a role in the generation of flushes.
Collapse
|
14
|
Girbig D, Keller K, Prelle K, Patchev V, Vonk R, Igl BW. A dynamic model of circadian rhythms in rodent tail skin temperature for comparison of drug effects. J Circadian Rhythms 2012; 10:1. [PMID: 22221596 PMCID: PMC3398330 DOI: 10.1186/1740-3391-10-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Accepted: 01/05/2012] [Indexed: 11/10/2022] Open
Abstract
Menopause-associated thermoregulatory dysfunction can lead to symptoms such as hot flushes severely impairing quality of life of affected women. Treatment effects are often assessed by the ovariectomized rat model providing time series of tail skin temperature measurements in which circadian rhythms are a fundamental ingredient. In this work, a new statistical strategy is presented for analyzing such stochastic-dynamic data with the aim of detecting successful drugs in hot flush treatment. The circadian component is represented by a nonlinear dynamical system which is defined by the van der Pol equation and provides well-interpretable model parameters. Results regarding the statistical evaluation of these parameters are presented.
Collapse
Affiliation(s)
- Dorothee Girbig
- Global Drug Discovery Statistics and Experimental Medicine Statistics, Bayer HealthCare, Berlin, Germany.
| | | | | | | | | | | |
Collapse
|
15
|
Uchida Y, Tokizawa K, Nakamura M, Mori H, Nagashima K. Estrogen in the medial preoptic nucleus of the hypothalamus modulates cold responses in female rats. Brain Res 2010; 1339:49-59. [PMID: 20416284 DOI: 10.1016/j.brainres.2010.04.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 04/08/2010] [Accepted: 04/09/2010] [Indexed: 12/01/2022]
Abstract
The present study examined the effect of the central administration of estrogen on responses to the cold. Estrogen or cholesterol was applied locally to the medial preoptic nucleus (MPO) or dorsomedial hypothalamic nucleus (DMH) of the hypothalamus in free-moving ovariectomized rats. Forty-eight hours after the application, rats had 2-h exposure at 10 or 25 degrees C. Body temperature (T(b)) and the tail surface temperature (T(tail)) were continuously measured by telemetry and thermography, respectively. The change of T(b) at 10 degrees C from the 25 degrees C baseline was higher in the estrogen application in the MPO than that in the cholesterol application; however, such difference was not observed in the DMH application. The uncoupling 1 protein mRNA level in the interscapular brown adipose tissue involved in non-shivering thermogenesis was not different between the estrogen and cholesterol applications in the MPO and DMH. T(tail) decreased in the cold, which was greater after the estrogen application in the MPO than after the cholesterol application. These results show that estrogen affects the MPO in female rats, changing T(b) in the cold. Moreover, suppression of heat loss from the tail may be involved in the mechanism.
Collapse
Affiliation(s)
- Yuki Uchida
- Faculty of Human Sciences, Waseda University, Tokorozawa, Saitama, Japan
| | | | | | | | | |
Collapse
|
16
|
Ikeda M, Egawa T, Yamauchi A, Sohda Y, Koga A, Tominaga K, Shuto H, Kataoka Y. Selective serotonin reuptake inhibitors fluvoxamine and paroxetine restore forced exercise-induced temperature dysregulation in ovariectomized mice. Eur J Pharmacol 2007; 579:439-44. [PMID: 18155696 DOI: 10.1016/j.ejphar.2007.11.043] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2007] [Revised: 11/06/2007] [Accepted: 11/15/2007] [Indexed: 10/22/2022]
Abstract
Hot flushes are one of the most frequent symptoms in menopausal women. Selective serotonin reuptake inhibitors (SSRIs) are considered to be first-line therapy for the treatment of hot flushes in women for whom hormone therapy is contraindicated. Recently, we have proposed forced exercise-induced flushing of tail skin in ovariectomized mice as a new experimental model of temperature dysregulation in menopausal hot flushes. In the present study, to validate this animal model as a tool for testing potential compounds for the treatment of menopausal hot flushes, we examined the effects of two SSRIs (fluvoxamine and paroxetine) on forced exercise-induced flushing of tail skin in ovariectomized mice, and compared it with that of estradiol replacement (1 mg/kg/week for 3 weeks, i.m.). Treatment with fluvoxamine (20 mg/kg, i.p.) or paroxetine (10 mg/kg, i.p.) completely inhibited forced exercise-induced flushing of tail skin in ovariectomized mice, and the effect of each was comparable to that of estradiol replacement. It is believed that the present findings provide the first experimental evidence to support the anti-flushing effects of SSRIs, such as fluvoxamine and paroxetine, in a clinical setting. An animal model with forced exercise probably serves as a useful experimental tool for evaluating the effects of different agents on hot flushes.
Collapse
Affiliation(s)
- Munehiko Ikeda
- Department of Pharmaceutical Care and Health Sciences, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Pawlyk AC, Cosmi S, Alfinito PD, Maswood N, Deecher DC. Effects of the 5-HT2A antagonist mirtazapine in rat models of thermoregulation. Brain Res 2006; 1123:135-44. [PMID: 17067560 DOI: 10.1016/j.brainres.2006.09.050] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2006] [Revised: 09/11/2006] [Accepted: 09/17/2006] [Indexed: 02/05/2023]
Abstract
Thermoregulation is a complex intercommunicative function requiring coordination between core body temperature (CBT), the central nervous system, and peripheral vasculature. In menopausal women, dysregulation of thermoregulatory mechanisms leads to hot flushes and night sweats. A previous study in ovariectomized (OVX) rats has suggested that mirtazapine can alleviate thermoregulatory dysfunction by blocking 5-HT(2A) receptor signaling. This is in opposition to other work in which 5-HT(2A) receptor blockade appeared to exacerbate thermoregulatory dysfunction in OVX rats. Thus, the goals of the present study were to reexamine the effects of mirtazapine on temperature regulation in OVX rat models and explore further the role of 5-HT(2A) receptor blockade. Mirtazapine exhibited potent functional antagonism (EC(50)=0.62 nM) at the cloned human 5-HT(2A) receptor. In the morphine-dependent model of thermoregulatory dysfunction, mirtazapine (10 mg/kg, i.p.) induced an increase in tail-skin temperature (TST) prior to naloxone administration. In the telemetry model, mirtazapine (0.3-3 mg/kg, i.p.) caused an increase in TST. However, at the highest dose tested (10 mg/kg, i.p.), mirtazapine induced a small but significant decrease in TST followed by an increase in TST. To examine this finding further, mirtazapine's effect on CBT was determined. Administration of mirtazapine (1-3 mg/kg, i.p.) resulted in a slight decrease in CBT but at the 10 mg/kg dose a dramatic decrease (-3.6 degrees C) in CBT was observed. These data support the concept that 5-HT(2A) receptors play a role in temperature regulation but that functional blockade of these receptors by mirtazapine is not a likely mechanism for restoring thermoregulatory processes in OVX rats.
Collapse
Affiliation(s)
- Aaron C Pawlyk
- Women's Health and Musculoskeletal Biology, Wyeth Research N3148B, 500 Arcola Rd., Collegeville, PA 19426, USA.
| | | | | | | | | |
Collapse
|
18
|
Bekku N, Yoshimura H, Araki H. Factors producing a menopausal depressive-like state in mice following ovariectomy. Psychopharmacology (Berl) 2006; 187:170-80. [PMID: 16788811 DOI: 10.1007/s00213-006-0395-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2005] [Accepted: 03/23/2006] [Indexed: 11/28/2022]
Abstract
RATIONALE Bilateral ovariectomy in female mice produces a menopausal depressive-like state but the factors responsible for the phenomenon are unknown. OBJECTIVES We elucidated methodological issues related to establishing this mouse model and investigated a possible mechanism underlying the depressive-like state of ovariectomized mice. METHODS We removed both ovaries of female ICR mice at 9 weeks of age. Changes in the immobility time during the forced swimming test as a function of the time interval between ovariectomy and behavioral testing were determined on nine different days after surgery. To assess behavioral specificity, the elevated plus-maze (EPM) behavior and spontaneous activity were measured. With respect to the effect of ovariectomy on the immobility time, we compared ICR mice with three other strains of mice (C57BL/6J, DBA/2N, and CD-1). Finally, we investigated the effects of (-)-2,5-dimethoxy-4-iodoamphetamine (DOI) and (+/-)-8-hydroxy-2-(N,N-di-n-propylamino) tetralin (8-OH-DPAT) on the immobility time of ovariectomized mice. RESULTS A significant effect on the prolongation of immobility was observed between 12 and 18 days after ovariectomy. Ovariectomy did not alter either the EPM behavior or spontaneous activity. Of the four strains of mice, only DBA mice did not show any significant prolongation of immobility after ovariectomy. Acute or chronic treatment with DOI (0.5 or 1.0 mg kg(-1)) significantly prevented the prolongation of immobility time, whereas acute and chronic treatments with 8-OH-DPAT (0.05, 0.5, or 1.0 mg kg(-1)) were ineffective. CONCLUSION The present findings have potentially important implications for evaluating a candidate substance for the management of mood disorders in menopausal women.
Collapse
Affiliation(s)
- Naoko Bekku
- Department of Pharmacology and Pharmacy, Ehime University Graduate School of Medicine, Shitsukawa, Toon-City, Ehime 791-0295, Japan
| | | | | |
Collapse
|
19
|
Sipe K, Leventhal L, Burroughs K, Cosmi S, Johnston GH, Deecher DC. Serotonin 2A receptors modulate tail-skin temperature in two rodent models of estrogen deficiency-related thermoregulatory dysfunction. Brain Res 2005; 1028:191-202. [PMID: 15527744 DOI: 10.1016/j.brainres.2004.09.012] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/10/2004] [Indexed: 10/26/2022]
Abstract
Menopause-associated thermoregulatory dysfunction, including hot flushes and night sweats, is effectively treated by hormonal therapies that include estrogens. Evidence suggests that estrogen regulates serotonin 2A (5-HT(2A)) receptor expression and that 5-HT(2A) receptors are involved in thermoregulation. Therefore, the role of 5-HT(2A) receptors in thermoregulation was assessed in two rat models of ovariectomy-induced thermoregulatory dysfunction. The first model is based on measurement of the tail-skin temperature (TST) increase following naloxone-induced withdrawal in morphine-dependent ovariectomized (OVX) rats (MD model), while the second model relies on telemetric assessment of diurnal TST changes in ovariectomized rats (telemetry model). Treatment with a 5-HT(2A/2C) receptor agonist, (-)-2,5-dimethoxy-4-iodoamphetamine hydrochloride (DOI), prevented the naloxone-induced TST increase in the MD model and restored normal active-phase TST in the telemetry model. The selective 5-HT(2A) receptor antagonist, MDL-100907, had no effect on the naloxone-induced flush when administered alone in the MD model, but it decreased DOI's ability to abate the flush. In the telemetry model, MDL-100907 attenuated the DOI-induced decrease in active-phase TST. Interestingly, MDL-100907 increased TST in both models when given alone, with the TST increase occurring prior to the naloxone-induced flush in the MD model. To evaluate the role of central nervous system (CNS) 5-HT(2A) receptors in TST regulation, DOI was administered in combination with a known peripheral 5-HT(2A/2C) receptor antagonist, xylamidine, in the MD model. Xylamidine had no effect on DOI's ability to abate the naloxone-induced flush. These results indicate that activation of central 5-HT(2A) receptors restores temperature regulation in two rodent models of ovariectomy-induced thermoregulatory dysfunction.
Collapse
Affiliation(s)
- Kimberly Sipe
- Women's Health Research Institute, Wyeth Research N3151A, 500 Arcola Rd., Collegeville, PA 19426, USA
| | | | | | | | | | | |
Collapse
|