501
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Maggi A. Estrogens, apoptosis and cells of neural origin. JOURNAL OF NEURAL TRANSMISSION. SUPPLEMENTUM 2001; 59:115-23. [PMID: 10961424 DOI: 10.1007/978-3-7091-6781-6_14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
In view of the relevant complexity of estradiol actions in the nervous system, we have proposed to utilize a reductionist approach and gain an insight on its role in neural cells via the identification of the genes target for this hormone. Once obtained a biochemical footprint of the responses elicited by E2 in the neural target cells we believe that the physiological effects exerted by this hormone will be more easily elucidated; in addition, we might find novel targets for drugs aimed at mimicking or blocking E2 effects. We here summarize preliminary results obtained in the cell line SK-ER3 appropriately engineered by us to express the ERalpha. We show that nip-2, one of the genes found to be regulated by E2, is involved in the mechanisms leading to cell death. This finding led us to investigate on estrogen effects on SK-ER3 apoptosis. We found that E2 has a significant anti-apoptotic activity in SKER3 cells. These results are in line with the recent reports from other laboratories indicating that E2 may prevent death of neural cells exposed to toxic stimuli. We conclude that these initial studies seem to support the strategy of our research and underline the strength of inverse genetics in the study of the physiology of sex hormone activities.
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Affiliation(s)
- A Maggi
- Center Milan Molecular Pharmacology Laboratory, Institute of Pharmacological Sciences, University of Milan, Italy
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502
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Abstract
Cellular genes that are mutated in neurodegenerative diseases code for proteins that are expressed throughout neural development. Genetic analysis suggests that these genes are essential for a broad range of normal neurodevelopmental processes. The proteins they code for interact with numerous other cellular proteins that are components of signaling pathways involved in patterning of the neural tube and in regional specification of neuronal subtypes. Further, pathogenetic mutations of these genes can cause progressive, sublethal alterations in the cellular homeostasis of evolving regional neuronal subpopulations, culminating in late-onset cell death. Therefore, as a consequence of the disease mutations, targeted cell populations may retain molecular traces of abnormal interactions with disease-associated proteins by exhibiting changes in a spectrum of normal cellular functions and enhanced vulnerability to a host of environmental stressors. These observations suggest that the normal functions of these disease-associated proteins are to ensure the fidelity and integration of developmental events associated with the progressive elaboration of neuronal subtypes as well as the maintenance of mature neuronal populations during adult life. The ability to identify alterations within vulnerable neuronal precursors present in pre-symptomatic individuals prior to the onset of irrevocable cellular injury may help foster the development of effective therapeutic interventions using evolving pharmacologic, gene and stem cell technologies.
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Affiliation(s)
- M F Mehler
- Laboratory of Developmental and Molecular Neuroscience, Department of Neurology, Rose F. Kennedy Center for Research in Mental Retardation and Developmental Disabilities, Albert Einstein College of Medicine, Bronx 10461, NY, USA.
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503
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Abstract
Primary prevention will become increasingly important as dementia prevalence increases and effective retardive therapies are developed. To date, only one randomized controlled trial (involving treatment of systolic hypertension) has demonstrated that the incidence of dementia can be reduced. Physicians should remain alert to possible secondary causes of dementia and correct these whenever possible. Primary and secondary prevention of stroke should reduce dementia related to cerebrovascular disease either directly or as a comorbid factor in Alzheimer's disease (AD). Epidemiological studies have revealed a number of risk factors for AD including genetic mutation, susceptibility genes, positive family history, Down's syndrome, age, sex, years of education, head trauma and neurotoxins. In case-control studies non-steroidal anti-inflammatory medication and estrogen replacement therapy appear to decrease the relative risk of developing AD. Further research to develop and test preventative therapies in AD and other dementias should be strongly encouraged.
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Affiliation(s)
- S E Black
- Department of Medicine, Neurology, University of Toronto, Ontario, Canada
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504
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Fillenbaum GG, Hanlon JT, Landerman LR, Schmader KE. Impact of estrogen use on decline in cognitive function in a representative sample of older community-resident women. Am J Epidemiol 2001; 153:137-44. [PMID: 11159158 DOI: 10.1093/aje/153.2.137] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The authors investigated whether postmenopausal estrogen use helps to maintain cognitive function; a brief screen, the Short Portable Mental Status Questionnaire (SPMSQ), was used. Information was gathered from a stratified, random sample of 1,907 African-American and White women (aged 65-100 years) participating in the longitudinal Duke Established Populations for Epidemiologic Studies of the Elderly project carried out in five urban and rural counties of North Carolina. All women were cognitively unimpaired in 1986-1987 and were evaluated 3 and 6 years later. Decline in cognitive function was measured as an increase of two or more errors on the SPMSQ and crossing of an SPMSQ threshold indicative of cognitive impairment. Recency and continuity of estrogen use were measured. Univariate analyses indicated that recent (crude odds ratio = 0.42, 95% confidence interval: 0.21, 0.86) and continuous (crude odds ratio = 0.32, 95% confidence interval: 0.13, 0.81) estrogen use reduced the risk of cognitive decline but not of cognitive impairment. After adjustment for demographic and health characteristics, protective effects became nonsignificant. While postmenopausal use of estrogen may be protective for Alzheimer's disease, current findings based on a brief cognitive screen suggest that it is not protective for cognitive decline related to aging.
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Affiliation(s)
- G G Fillenbaum
- Center for the Study of Aging and Human Development, Duke University Medical Center, Durham, NC 27710, USA.
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505
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Cutler NR, Sramek JJ. Review of the next generation of Alzheimer's disease therapeutics: challenges for drug development. Prog Neuropsychopharmacol Biol Psychiatry 2001; 25:27-57. [PMID: 11263756 DOI: 10.1016/s0278-5846(00)00147-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
1. AD is believed to stem from dysfunctional cholinergic signaling in the regions of the brain associated with memory and cognition. 2. The occurrence of AD in afflicted individuals correlates with an increase in the accumulation of A beta-rich senile plaques and neurofibrillary tangles in the brain. 3. Currently, the only FDA-approved AD therapies are a group of acetylcholinesterase inhibitors which slow the turnover of the neurotransmitter acetylcholine in the synapse. 4. Many other compounds which target other aspects of the disease, such as reducing neuronal damage and limiting oxidation, are in clinical trials. These include monoamine oxidase (MAO-B) inhibitors, NSAIDs, antioxidants and estrogen, among others. 5. Recent research discoveries have more completely defined the molecular nature of AD, and are generating new approaches for treatment. One idea is to limit the ability of the protein tau to become phosphorylated in hopes that this will limit the formation of neurofibrillary tangles in the brain. 6. A separate approach that is being pursued is to prevent formation and accumulation of A beta plaques. This may be accomplished by either regulating gamma-secretase activity, or using anti-beta-amyloid antibodies to reduce the size of existing plaques. 7. Employing improved procedural and technological approaches during clinical trials, such as bridging studies, dynabridge studies and PET analysis, promises to streamline the drug development process. 8. The use of biomarkers and MRI analysis may be an effective means by which to identify the disease early. Consequently, early intervention treatment therapies may be an effective way of delaying onset of the disease. 9. Long term AD studies, particularly those focusing on the MCI population, are likely to provide statistically valid results using a smaller study population.
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Affiliation(s)
- N R Cutler
- California Clinical Trials, Beverly Hills, 90211, USA.
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506
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Abstract
This review highlights recent evidence from clinical and basic science studies supporting a role for estrogen in neuroprotection. Accumulated clinical evidence suggests that estrogen exposure decreases the risk and delays the onset and progression of Alzheimer's disease and schizophrenia, and may also enhance recovery from traumatic neurological injury such as stroke. Recent basic science studies show that not only does exogenous estradiol decrease the response to various forms of insult, but the brain itself upregulates both estrogen synthesis and estrogen receptor expression at sites of injury. Thus, our view of the role of estrogen in neural function must be broadened to include not only its function in neuroendocrine regulation and reproductive behaviors, but also to include a direct protective role in response to degenerative disease or injury. Estrogen may play this protective role through several routes. Key among these are estrogen dependent alterations in cell survival, axonal sprouting, regenerative responses, enhanced synaptic transmission and enhanced neurogenesis. Some of the mechanisms underlying these effects are independent of the classically defined nuclear estrogen receptors and involve unidentified membrane receptors, direct modulation of neurotransmitter receptor function, or the known anti-oxidant activities of estrogen. Other neuroprotective effects of estrogen do depend on the classical nuclear estrogen receptor, through which estrogen alters expression of estrogen responsive genes that play a role in apoptosis, axonal regeneration, or general trophic support. Yet another possibility is that estrogen receptors in the membrane or cytoplasm alter phosphorylation cascades through direct interactions with protein kinases or that estrogen receptor signaling may converge with signaling by other trophic molecules to confer resistance to injury. Although there is clear evidence that estradiol exposure can be deleterious to some neuronal populations, the potential clinical benefits of estrogen treatment for enhancing cognitive function may outweigh the associated central and peripheral risks. Exciting and important avenues for future investigation into the protective effects of estrogen include the optimal ligand and doses that can be used clinically to confer benefit without undue risk, modulation of neurotrophin and neurotrophin receptor expression, interaction of estrogen with regulated cofactors and coactivators that couple estrogen receptors to basal transcriptional machinery, interactions of estrogen with other survival and regeneration promoting factors, potential estrogenic effects on neuronal replenishment, and modulation of phenotypic choices by neural stem cells.
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507
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Wu F, Ames R, Evans MC, France JT, Reid IR. Determinants of sex hormone-binding globulin in normal postmenopausal women. Clin Endocrinol (Oxf) 2001; 54:81-7. [PMID: 11167930 DOI: 10.1046/j.1365-2265.2001.01183.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To examine the factors influencing the levels of sex hormone-binding globulin (SHBG) in normal postmenopausal women by assessing the relationship between SHBG and measured anthropometric, metabolic and hormonal variables. DESIGN Cross-sectional, observational study. SUBJECTS AND METHODS Seventy normal postmenopausal women aged 47-71 years (mean 58 years), participated in the study. Information was collected on medical, reproductive and smoking history, alcohol use, dietary intake and physical activity. Body composition measurements using dual-energy absorptiometry, and analyses of biochemical and hormonal indices were performed. RESULTS Bivariate correlation coefficients indicated that SHBG was inversely related to body weight (r = - 0.44), fat mass (r = - 0.35), and abdominal obesity (r = - 0.42). It was also inversely related to the glucose and insulin levels during an oral glucose tolerance test (- 0.24 < r < - 0.40), serum oestradiol (r = - 0.26), and physical activity (r = - 0.24). Multiple regression analysis indicated that significant independent correlates of SHBG concentration were fat mass, physical activity, alcohol intake, serum oestradiol, and insulin-like growth factor-1, all having a negative impact on SHBG. CONCLUSIONS From these observed associations, it is concluded that maintenance of body weight, moderate alcohol consumption, and physical activity will tend to reduce SHBG concentrations in postmenopausal women, thereby increasing the levels of free oestradiol. This mechanism could mediate the beneficial effects of these factors in preventing the development of osteoporosis and cardiovascular disease.
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Affiliation(s)
- F Wu
- Department of Medicine, University of Auckland, Auckland, New Zealand
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508
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Duff SJ, Hampson E. A beneficial effect of estrogen on working memory in postmenopausal women taking hormone replacement therapy. Horm Behav 2000; 38:262-76. [PMID: 11104644 DOI: 10.1006/hbeh.2000.1625] [Citation(s) in RCA: 183] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent neurophysiological data suggest that the prefrontal cortex (PFC) may be susceptible to modulation by estrogen. In humans, the PFC mediates a number of cognitive processes that contribute to memory function, particularly working memory. The present study examined whether memory tasks that recruit PFC-dependent information processing might exhibit estrogen sensitivity in women. Performance on several memory tasks, including measures of working memory, was evaluated in three groups of postmenopausal women: (1) women who were tested when taking estrogen only (n = 38, M(age) = 55.1 years), (2) women who were tested when taking estrogen and a progestin concurrently (n = 23, M(age) = 55.9 years), and (3) women who were not taking hormone replacement therapy (n = 35, M(age) = 56.0 years). Estrogen users exhibited significantly better performance on a verbal task and on a spatial task, each with a prominent working memory component, but did not differ from nonusers on control tasks involving simple passive recall. These findings are consistent with the hypothesis that estrogen is active within PFC and is capable of influencing functions dependent on this region. The results of this study raise the possibility that estrogen may play a role in maintaining certain frontal lobe functions in women.
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Affiliation(s)
- S J Duff
- Department of Psychology, University of Western Ontario, London, Ontario N6A 5C2, Canada
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509
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Maggi A, Vegeto E, Brusadelli A, Belcredito S, Pollio G, Ciana P. Identification of estrogen target genes in human neural cells. J Steroid Biochem Mol Biol 2000; 74:319-25. [PMID: 11162940 DOI: 10.1016/s0960-0760(00)00107-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In mammals, estrogens have a multiplicity of effects ranging from control of differentiation of selected brain nuclei, reproductive functions, sexual behavior. In addition, these hormones influence the manifestation of disorders like depression and Alzheimer's. Study of the cells target for the hormone has shown that estrogen receptors (ERs) are expressed in all known neural cells, including microglia. In view of the potential interest in the use of estrogens in the therapy of several pathologies of the nervous system, it would be of interest to fully understand the mechanism of estrogen activity in the various neural target cells and get an insight on the molecular means allowing the hormone to display such a variety of effects. We have proposed the use of a reductionist approach for the systematic understanding of the estrogen activities in each specific type of target cell. Thus, we have generated a model system in which to study the activation of one of the known (ERs), estrogen receptor alpha. This system allowed us to identify a number of novel genes which expression may be influenced following the activation of this receptor subtype by estradiol (E(2)). We here report on data recently obtained by the study of one of these target genes, nip2, which encodes a proapoptotic protein product. We hypothesize that nip2 might be an important molecular determinant for estrogen anti-apoptotic activity in cells of neural origin and represents a potential target for drugs aimed at mimicking the E(2) beneficial effects in neural cells.
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Affiliation(s)
- A Maggi
- Center Milan Molecular Pharmacology Laboratory, Institute of Pharmacological Sciences, University of Milan, Via Balzaretti 9, 20133, Milan, Italy.
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510
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Paganini-Hill A, Clark LJ. Preliminary assessment of cognitive function in breast cancer patients treated with tamoxifen. Breast Cancer Res Treat 2000; 64:165-76. [PMID: 11194452 DOI: 10.1023/a:1006426132338] [Citation(s) in RCA: 188] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Tamoxifen is an anti-estrogen used in the treatment of breast cancer and to reduce the incidence of breast cancer in high risk women. Although the brain is an estrogen target organ and several studies have found a beneficial effect of estrogen on cognitive function, the effect of tamoxifen on cognition has not been reported. Therefore, we initiated a follow-up study of women who had participated in a study of breast cancer to assess the effect of tamoxifen treatment on cognitive function. METHODS We recruited previously interviewed patients who were cases in a population-based case-control study of 2,653 women with primary breast cancer diagnosed between 1987 and 1996 at ages 55-72 years in Los Angeles County, California, USA. In November 1997, each case was mailed a follow-up questionnaire. Cognitive function was assessed by (1) clock drawing. (2) copying a box drawing, and (3) narrative writing to describe a pictured scene. Women reporting treatment with tamoxifen were categorized as standard-term users (4-5 years), short-term users (< 4 years) or long-term users (6 + years) and compared to never users. Tamoxifen users were also classified as past or current users. Differences in the mean cognitive test scores were tested after adjusting for age, age at diagnosis, stage of disease, radiation therapy, chemotherapy, race, education, marital status, previous use of oral contraceptives, type of menopause, age at last menstrual period, previous use of hormone replacement therapy, and depressive symptoms using analysis of covariance. All p-values for differences in the proportion of women who had errors on the tests are 2-sided and adjusted for age, stage of disease at diagnosis, and chemotherapy. FINDINGS Information from 1,163 women aged 57-75 years of age was analyzed; 710 had taken tamoxifen. There was little difference between women who had used tamoxifen for the standard five years and never users on the three cognitive tests. However, more women who had used tamoxifen for the standard term reported seeing their physician for memory problems than non-users (3.8% vs 1.5%, p = 0.04). This was especially true for current users of standard-term (8.0%, p = 0.003). Current users also had a significantly lower mean complexity score (p = 0.03) on the narrative writing task. No differences were seen between past users and non-users. INTERPRETATION Our study suggests that current use of tamoxifen may adversely effect cognition. Further study of tamoxifen and cognition is needed so that healthy women considering tamoxifen for the primary prevention of breast cancer have comprehensive information about the side effects of the treatment.
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Affiliation(s)
- A Paganini-Hill
- Department of Preventive Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, USA.
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511
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McEwen BS. Allostasis, allostatic load, and the aging nervous system: role of excitatory amino acids and excitotoxicity. Neurochem Res 2000; 25:1219-31. [PMID: 11059796 DOI: 10.1023/a:1007687911139] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The adaptive responses of the body to challenges, often known as "stressors", consists of active responses that maintain homeostasis. This process of adaptation is known as "allostasis", meaning "achieving stability through change". Many systems of the body show allostasis, including the autonomic nervous system and hypothalamo-pituitary-adrenal (HPA) axis and they help to re-establish or maintain homeostasis through adaptation. The brain also shows allostasis, involving the activation of nerve cell activity and the release of neurotransmitters. When the individual is challenged repeatedly or when the allostatic systems remain turned on when no longer needed, the mediators of allostasis can produce a wear and tear on the body that has been termed "allostatic load". Examples of allostatic load include the accumulation of abdominal fat, the loss of bone minerals and the atrophy of nerve cells in the hippocampus. Circulating stress hormones play a key role, and, in the hippocampus, excitatory amino acids and NMDA receptors are important mediators of neuronal atrophy. The aging brain seems to be more vulnerable to such effects, although there are considerable individual differences in vulnerability that can be developmentally determined. Yet, at the same time, excitatory amino acids and NMDA receptors mediate important types of plasticity in the hippocampus. Moreover, the brain retains considerable resilience in the face of stress, and estrogens appear to play a role in this resilience. This review discusses the current status of work on underlying mechanisms for these effects.
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Affiliation(s)
- B S McEwen
- Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, Rockfeller University, New York, NY 10021, USA.
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512
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Eberling JL, Reed BR, Coleman JE, Jagust WJ. Effect of estrogen on cerebral glucose metabolism in postmenopausal women. Neurology 2000; 55:875-7. [PMID: 10994014 DOI: 10.1212/wnl.55.6.875] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
PET was used to evaluate the effect of estrogen use on regional cerebral glucose metabolism in postmenopausal women. Women receiving estrogen replacement therapy (ERT+), women not receiving estrogen (ERT-), and women with AD were studied. The ERT- group showed metabolic ratios that were intermediate to the ERT+ and AD groups, although they did not show any signs of cognitive impairment. These findings show an effect of estrogen depletion on brain metabolic activity.
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Affiliation(s)
- J L Eberling
- Center for Functional Imaging Lawrence Berkeley Laboratory, University of California, Berkeley, CA, USA.
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513
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Verghese J, Kuslansky G, Katz MJ, Sliwinski M, Crystal HA, Buschke H, Lipton RB. Cognitive performance in surgically menopausal women on estrogen. Neurology 2000; 55:872-4. [PMID: 10994013 DOI: 10.1212/wnl.55.6.872] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Estrogen replacement therapy (ERT) may help maintain normal cognitive function. Nondemented surgically menopausal women on ERT (n = 10) enrolled in a longitudinal aging study performed better than age- and education-matched control subjects (n = 25) on selected tests of verbal memory and constructional ability. These results suggest that ERT initiated soon after surgical menopause can have long-term neuroprotective effects in cognitively intact women.
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Affiliation(s)
- J Verghese
- Einstein Aging Study , Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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514
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Silva I, Mello LE, Freymüller E, Haidar MA, Baracat EC. Estrogen, progestogen and tamoxifen increase synaptic density of the hippocampus of ovariectomized rats. Neurosci Lett 2000; 291:183-6. [PMID: 10984637 DOI: 10.1016/s0304-3940(00)01410-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The effects of gonadal steroids or tamoxifen over the synaptic density of the CA1 region of the hippocampus was investigated in ovariectomized (OVX) rats. Chronic oral administration of conjugated equine estrogen, conjugated equine medroxyprogesterone, a combination of both or tamoxifen was performed in ovariectomized (OVX) rats over a period of 60 days. Synaptic density of the stratum radiatum of the CA1 region was evaluated by means of electron microscopy. Significant increases in the range of 34-49% were found for treated animals as compared to OVX controls not subject to hormonal replacement. Our results confirm previously reported effects of estradiol over synaptic density in this region and reports for the first time an effect of medroxyprogesterone (alone or in combination with estrogen) and tamoxifen. Our findings support the notion that hormonal replacement therapy and tamoxifen might have beneficial effects for cognitive function.
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Affiliation(s)
- I Silva
- Department of Gynecology, Universidade Federal de São Paulo, Rua Botucatu 862, 04023-062, São Paulo, Brazil
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515
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López-Jaramillo P, Terán E. Improvement in functions of the central nervous system by estrogen replacement therapy might be related with an increased nitric oxide production. ENDOTHELIUM : JOURNAL OF ENDOTHELIAL CELL RESEARCH 2000; 6:263-6. [PMID: 10475089 DOI: 10.3109/10623329909078493] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Estrogen promotes neurons growth, prevents neuronal cell atrophy and regulates synaptic plasticity. Administration of estrogen protects neurons against oxidative stress, excitotoxins, and beta-amyloid-induced toxicity in cell culture. It has been shown that estrogen treatment reduces the serum monoamino oxidase levels and might regulate learning and memory. Nitric oxide (NO) is a retrograde messenger and long-term potentiation can be block using NO-synthase inhibitors or can be prevent with NO-scavengers. NO synthase is widespread in the central nervous system and acts as neurotransmitter/neuromodulator. The actions of serotonin, bradykinin, endothelin, acetylcholine and noradrenaline might be linked to NO formation. Estrogen induces activity of constitutive NO synthase and estrogen replacement therapy in postmenopausal women increases significantly circulating nitrite plus nitrate levels. The effect of estrogen on NO synthesis is rapid and is maintained with repeated administration. We demonstrated the effects of estrogen replacement therapy in Andean postmenopausal women were associated with a significantly increase in plasma levels of nitrite plus nitrate. Our hypothesis is that beneficial effect of estrogen replacement therapy on involutive depression in postmenopausal women is mediated by increase in NO production by central nervous system.
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Affiliation(s)
- P López-Jaramillo
- Mineral Metabolism Unit, Faculty of Medicine, Central University of Ecuador, Quito
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516
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Raloxifene and Estrogen Effects on Quality of Life in Healthy Postmenopausal Women. Obstet Gynecol 2000. [DOI: 10.1097/00006250-200009000-00008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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517
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Ross J, Zinn A, McCauley E. Neurodevelopmental and psychosocial aspects of Turner syndrome. MENTAL RETARDATION AND DEVELOPMENTAL DISABILITIES RESEARCH REVIEWS 2000; 6:135-41. [PMID: 10899807 DOI: 10.1002/1098-2779(2000)6:2<135::aid-mrdd8>3.0.co;2-k] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Turner syndrome (TS) is the complex phenotype of human females with complete or partial absence of the second sex chromosome, or monosomy X. A characteristic neurocognitive and psychosocial profile has also been described in TS females. Typically, specific deficits in visual-spatial/perceptual abilities, nonverbal memory function, motor function, executive function, and attentional abilities occur in TS children and adults of varying races and socioeconomic status. TS-associated psychosocial difficulties occur in the areas of maturity and social skills. We hypothesize that a subset of the neurocognitive deficits (visual-spatial/perceptual abilities) are genetically determined and result from abnormal expression of one or more X chromosome genes. In addition, a different subset of these neurocognitive deficits (memory, reaction time, and speeded motor function) result from estrogen deficiency and are at least somewhat reversible with estrogen treatment. The TS-associated psychosocial problems are most likely linked to these core neurocognitive deficits and do not reflect a separate and independent component of the syndrome. Turner syndrome research has progressed significantly over the last decade. The field has moved from descriptive reports based on single individuals or small clinical samples to the use of experimental designs with larger, more diverse and representative samples. This degree of variability among individuals with Turner syndrome in all domains (karyotype or genetic constitution, physical attributes, neurocognitive and social functioning) suggests the need to identify risk and protective factors contributing to the heterogeneity in the phenotype. Active education about TS and participation in patient advocacy groups such as the Turner Syndrome Society of the United States (http://www. turner-syndrome-us.org/) has provided new information for TS adults and families as well as a supportive peer group. MRDD Research Reviews 2000;6:135-141.
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Affiliation(s)
- J Ross
- Department of Pediatrics, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
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518
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Abstract
UNLABELLED Raloxifene is a selective estrogen receptor modulator that partially mimics the effects of estrogens in bone and the cardiovascular system, while functioning as an antiestrogen in endometrial and breast tissue. In randomised placebo-controlled studies involving postmenopausal women or patients with osteoporosis, raloxifene 60 to 150 mg/day was effective in increasing bone mineral density (BMD) over 12- to 36-month periods. At the 60 mg/day recommended dosage, increases of 1.6 to 3.4%, 0.9 to 2.3% and 1.0 to 1.6% were reported in lumbar spine, femoral neck and total hip, respectively, versus < or =0.5% with placebo. Raloxifene 60 or 120 mg/day decreased the risk of vertebral fractures over a 36-month period in postmenopausal patients with osteoporosis. Significant reductions in radiographic fracture risk versus placebo (30 and 50%) occurred regardless of whether patients had existing fractures at baseline. Although raloxifene did not affect the overall incidence of nonvertebral fractures, a reduction in the incidence of ankle fracture was reported in comparison with placebo. In postmenopausal women, raloxifene 60 mg/day significantly reduced serum levels of total and low density lipoprotein cholesterol from baseline, compared with placebo. High density lipoprotein cholesterol and triglyceride levels were unaffected. Raloxifene 60 or 120 mg/day reduced the risk of invasive breast cancer by 76% during a median of 40 months' follow-up in postmenopausal patients with osteoporosis and no history of breast cancer. A relative risk reduction of 90% was reported for estrogen-receptor positive invasive breast cancers; estrogen-receptor negative cancer risk was unaffected by raloxifene. Raloxifene was generally well tolerated in clinical trials at dosages up to 150 mg/day. Adverse events thought to be related to raloxifene treatment were hot flushes and leg cramps. Venous thromboembolism was the only serious adverse event thought to be related to raloxifene treatment and a relative risk of 3.1 compared with placebo treatment was reported in patients with osteoporosis. Vaginal bleeding occurred in < or =6.4% of raloxifene-treated women but was reported by 50 to 88% of those receiving estrogens or hormone replacement therapy (HRT). Raloxifene treatment was not associated with stimulatory effects on the endometrium. CONCLUSIONS Raloxifene significantly increases BMD in postmenopausal women and reduces vertebral fracture risk in patients with osteoporosis. In clinical trials, raloxifene was generally well tolerated compared with placebo and HRT, although its propensity to cause hot flushes precludes use in women with vasomotor symptoms. In particular, the lack of stimulatory effects on the endometrium and the reduction in invasive breast cancer incidence indicate raloxifene as an attractive alternative to HRT for the management of postmenopausal osteonorosis.
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Affiliation(s)
- D Clemett
- Adis International Limited, Mairangi Bay, Auckland, New Zealand
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519
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Gandy S, Petanceska S. Regulation of Alzheimer beta-amyloid precursor trafficking and metabolism. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1502:44-52. [PMID: 10899430 DOI: 10.1016/s0925-4439(00)00031-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Alzheimer's disease (AD) is characterized by the intracranial accumulation of the 4 kDa amyloid-beta peptide (Abeta), following proteolysis of a approximately 700-amino acid, integral membrane precursor, the Alzheimer amyloid precursor protein (APP). The best evidence causally linking APP to AD has been provided by the discovery of mutations within the APP coding sequence that segregate with disease phenotypes in autosomal dominant forms of familial AD (FAD). Though FAD is rare ( < 10% of all AD), the hallmark features (amyloid plaques, neurofibrillary tangles, synaptic and neuronal loss, neurotransmitter deficits and dementia) are indistinguishable when FAD is compared with typical, common, 'non-familial', or sporadic, AD (SAD). Studies of some clinically relevant mutant APP molecules from FAD families have yielded evidence that APP mutations can lead to the enhanced generation or aggregability of Abeta, consistent with a pathogenic role in AD. Other genetic loci for FAD have been discovered which are distinct from the immediate regulatory and coding regions of the APP gene, indicating that defects in molecules other than APP can also specify cerebral amyloidogenesis and FAD. To date, all APP and non-APP FAD mutations can be demonstrated to have the common feature of promoting amyloidogenesis of Abeta. Epidemiological studies indicate that postmenopausal women on estrogen replacement therapy (ERT) have their relative risk of developing SAD diminished by about one third as compared with age-matched women not receiving ERT [M.X. Tang, D. Jacobs, Y. Stern, K. Marder, P. Schofield, B. Gurland, H. Andrews, R. Mayeux, Effect of estrogen during menopause on risk and age at onset of Alzheimer's disease, Lancet 348 (2000) 429432]. Because of the key role of cerebral Abeta accumulation in initiating AD pathology, it is most attractive that estradiol might modulate SAD risk or age-at-onset by inhibiting Abeta accumulation. A possible mechanistic basis for such a scenario is reviewed here.
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Affiliation(s)
- S Gandy
- Department of Psychiatry, The Nathan S. Kline Institute for Psychiatric Research, New York University, Orangeburg, NY 10962, USA.
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520
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Abstract
While the ovaries are the principal source of systemic estrogen in the premenopausal nonpregnant woman, other sites of estrogen biosynthesis are present throughout the body and these become the major sources of estrogen beyond menopause. These sites include the mesenchymal cells of the adipose tissue and skin, osteoblasts, and perhaps chondrocytes in bone, vascular endothelial and aortic smooth muscle cells, as well as a number of sites in the brain including the medial preoptic/anterior hypothalamus, the medial basal hypothalamus and the amygdala. These extragonadal sites of estrogen biosynthesis possess several fundamental features which differ from those of the ovaries. Principally, the estrogen synthesized within these compartments is probably only biologically active at a local tissue level in a paracrine or 'intracrine' fashion. Thus the total amount of estrogen synthesized by these extragonadal sites may be small, but the local tissue concentrations achieved are probably quite high, and exert significant biological influence locally. Thus these sources of estrogen play an important but hitherto largely unrecognized, physiological and pathophysiological role.
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Affiliation(s)
- E R Simpson
- Prince Henry's Institute of Medical Research, Clayton Vic, Australia.
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521
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Abstract
Despite a recent trend toward improvement in the U.S. breast cancer mortality rate, breast cancer incidence (182,800 new cases anticipated in 2000) and mortality figures (over 40,800 anticipated deaths) remain the highest and second highest, respectively, of all cancers in U.S. women. In 1998, the selective-estrogen-receptor-modulator (SERM) tamoxifen achieved positive results in the Breast Cancer Prevention Trial (BCPT), leading to the Food and Drug Administration (FDA) approval of tamoxifen for risk reduction in women at high risk of breast cancer (the historic first FDA approval of a cancer preventive agent). This brought about a paradigm shift in new approaches for controlling breast cancer toward pharmacologic preventive regimens, called chemoprevention. This paper presents a comprehensive clinical review of breast cancer prevention study, highlighting issues of the extensive study of tamoxifen. These issues include the record of primary tamoxifen results in several breast-cancer risk-reduction settings (primary, adjuvant, and ductal carcinoma in situ [DCIS]); critical secondary BCPT risk-benefit findings (including quality of life issues) and their effects on counseling patients on use of tamoxifen for prevention; ethic minorities; optimal tamoxifen dose/duration; and potential impact on mortality and other issues involved with potential net benefit to society. Other breast-cancer chemoprevention issues reviewed here include women at high genetic risk (especially BRCA1 mutation carriers); raloxifene in breast cancer prevention; other SERMs; SERM resistance; and new agents and combinations currently in development. Very recent developments involving PPAR-gamma ligands, COX-2 inhibitors, and RXR-ligands are discussed in the section on new drug development.
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Affiliation(s)
- P H Brown
- Breast Center, Department of Medicine, Baylor College of Medicine, Houston, Texas, USA
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522
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Grodstein F, Chen J, Pollen DA, Albert MS, Wilson RS, Folstein MF, Evans DA, Stampfer MJ. Postmenopausal hormone therapy and cognitive function in healthy older women. J Am Geriatr Soc 2000; 48:746-52. [PMID: 10894312 DOI: 10.1111/j.1532-5415.2000.tb04748.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Accumulating biologic evidence suggests that estrogen is related to cognitive function. Several epidemiologic investigations have reported that hormone therapy may reduce the risk of Alzheimer's disease. However, fewer studies have examined the relation of postmenopausal hormone use to general cognitive function in nondemented older women. Thus, we examined the association of hormone therapy to performance on four cognitive tests among healthy participants of the Nurses' Health Study. DESIGN Cohort study. SETTING The Nurses' Health Study, an ongoing prospective cohort study begun in 1976. PARTICIPANTS From the Nurses' Health Study, 2138 women aged 70-78 years. MEASUREMENTS From 1995-1999 we administered four cognitive tests (Telephone Interview for Cognitive Status (TICS), immediate and delayed recall of the East Boston Memory Test (EBMT), and verbal fluency) by telephone. Hormone use was ascertained from biennial questionnaires beginning in 1976. Linear and logistic regression models were used to calculate multivariate-adjusted differences in scores and relative risks of a low score for never users compared to current and past hormone users. RESULTS After adjustment for confounders, neither current nor long-term hormone users demonstrated better performance on an overall measure of cognition (TICS), or on three tests of verbal memory (immediate and delayed recall of the EBMT, immediate recall of the TICS 10-word list) than never users. On the test of verbal fluency, current hormone users scored significantly better than never users (linear regression estimate of the difference in score = 0.78 points, 95% confidence interval (CI) 0.19-0.38, P = .01 for any current use; and 0.91 points, 95% CI 0.28-1.54, P = .005 for > or = 5 years current use). Current hormone users also had a 30% decrease (RR = 0.70, 95% CI 0.45-1.09) in their risk of a low score on the test of verbal fluency. These results were similar for women taking estrogen alone and estrogen combined with a progestin. CONCLUSIONS Verbal fluency may be enhanced among women taking postmenopausal hormones, however, there is little support for better overall cognitive function in hormone users than nonusers.
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Affiliation(s)
- F Grodstein
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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523
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Simpson E, Rubin G, Clyne C, Robertson K, O'Donnell L, Jones M, Davis S. The role of local estrogen biosynthesis in males and females. Trends Endocrinol Metab 2000; 11:184-8. [PMID: 10856920 DOI: 10.1016/s1043-2760(00)00254-x] [Citation(s) in RCA: 160] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Natural (human) and experimental (mouse) models of estrogen insufficiency have revealed hitherto unexpected roles for estrogens in both males and females. In postmenopausal women, and in men, estrogen no longer has a major role as a circulating hormone, but rather it functions locally as a paracrine or even 'intracrine' factor in tissue sites where it is formed. As a consequence, the tissue-specific nature of aromatase production assumes physiological and pathophysiological significance. The availability of circulating precursors is also important in sites where there is no local supply of C19 precursors, particularly in elderly women. The potential clinical significance of these findings in terms of the development of new therapeutic modalities is discussed.
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Affiliation(s)
- E Simpson
- Prince Henry's Institute of Medical Research, PO Box 5152, Clayton, Victoria 3168, Australia.
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524
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Marder K, Sano M. Estrogen to treat Alzheimer's disease: too little, too late? So what's a woman to do? Neurology 2000; 54:2035-7. [PMID: 10851358 DOI: 10.1212/wnl.54.11.2035] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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525
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Wang PN, Liao SQ, Liu RS, Liu CY, Chao HT, Lu SR, Yu HY, Wang SJ, Liu HC. Effects of estrogen on cognition, mood, and cerebral blood flow in AD: a controlled study. Neurology 2000; 54:2061-6. [PMID: 10851363 DOI: 10.1212/wnl.54.11.2061] [Citation(s) in RCA: 216] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To examine the effects of estrogen therapy on cognition, mood, and cerebral blood flow in patients with AD. BACKGROUND Some studies have suggested estrogen may be effective in the treatment of AD. However, most of these studies were not controlled adequately. METHODS Fifty female AD patients were recruited in a randomized, double-blind, placebo-controlled 12-week trial. Each member of the estrogen-treated group received conjugated estrogen (Premarin) 1.25 mg/day. The primary outcome measures were the Cognitive Ability Screening Instrument (CASI), Clinical Dementia Rating (CDR), and Clinician Interview-Based Impression of Change (CIBIC-plus). The secondary outcome measures were Behavioral Pathology in Alzheimer's Disease (BEHAVE-AD), Hamilton Anxiety Rating Scale (HARS), Hamilton Depression Rating Scale (HDRS), and 99mTc hexamethylpropylene amine oxime SPECT of the brain. RESULTS No meaningful differences were found between the outcome measures (CASI, CDR, CIBIC-plus, BEHAVE-AD, HARS, HDRS, and cerebral blood flow) taken from the estrogen-treated group and those from the control group. CONCLUSION A 1.25-mg/day dose of Premarin administered for 12 consecutive weeks does not produce a meaningful effect on cognitive performance, dementia severity, behavior, mood, and cerebral perfusion in female AD patients. Because estrogen therapy has been suspected of yielding adverse effects, and its therapeutic effectiveness is in doubt, additional evaluation of its role in AD treatment ought to be conducted.
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Affiliation(s)
- P N Wang
- Neurological Institute, Department of Nuclear Medicine, Taipei Veterans General Hospital & National Yang-Ming University School of Medicine, Taipei, Taiwan
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526
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Giap BT, Jong CN, Ricker JH, Cullen NK, Zafonte RD. The hippocampus: anatomy, pathophysiology, and regenerative capacity. J Head Trauma Rehabil 2000; 15:875-94. [PMID: 10785620 DOI: 10.1097/00001199-200006000-00003] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Cognitive deficits following insults to the central nervous system-particularly those involving the hippocampus and related structures-are often persistent and severely debilitating. Progress has been made in establishing the role of the hippocampus in integrating information in the formation of memory necessary for subsequent recollection of information. The present article will review anatomic, physiological, and functional aspects of the hippocampus in reference to learning and memory. Both animal and human hippocampal pathophysiological processes will be explored. Adaptive and maladaptive central nervous system responses will be reviewed, with a special emphasis on neurogenesis. Ideally, physiological and cellular compensatory responses ought to parallel clinical observation. However, this association is not clearly established. Finally, the current understanding of neuromodulatory mechanisms (although quite preliminary) will also be discussed.
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Affiliation(s)
- B T Giap
- Brain Injury Program, Kaiser Foundation Rehabilitation Center, Vallejo, California 94589-2485, USA
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527
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Abstract
To determine whether ovariectomy exacerbates age-related cognitive decline, the performance of 6 aged monkeys that had been ovariectomized early in life (OVX-Aged) was compared to that of 8 age-matched controls with intact ovaries (INT-Aged) and that of 5 young controls with intact ovaries (INT-Young) in tasks of visual recognition memory, object and spatial memory, and executive function. The OVX-Aged monkeys were marginally more impaired than the INT-Aged monkeys on the delayed nonmatching-to-sample with a 600-s delay. In contrast, they performed significantly better than the INT-Aged controls on the spatial condition of the delayed recognition span test. The hypothesis that prolonged estrogenic deprivation may exaggerate the age-related decline in visual recognition memory will require additional support. However, the findings suggest that long-term ovariectomy may protect against the development with aging of spatial memory deficits.
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Affiliation(s)
- A Lacreuse
- Division of Neuroscience, Yerkes Regional Primate Research Center, Emory University, Atlanta, Georgia 30322, USA.
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528
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Hemminki E. Hormone replacement therapy: discrepancies between evidence and recommendations. Scand J Public Health 2000; 28:81-3. [PMID: 10954132 DOI: 10.1177/140349480002800201] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Postmenopausal hormone therapy is widely used to prevent diseases. This is not, however, based on the kind of evidence that is normally required of a preventive drug therapy: it is based on intermediary outcomes of trials and non-experimental studies. Many reasons can be postulated for the fact that we know little of this old and widely used therapy. To remedy the current situation, we should encourage randomised controlled trials, reveal the insufficiency of the current evidence, and challenge the drug industry's biased influence.
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529
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Nourhashémi F, Ousset PJ, Guyonnet S, Andrieu S, Rolland Y, Adoue D, Vellas B, Albarède JL. [Alzheimer's disease: from pathology to preventive methods?]. Rev Med Interne 2000; 21:524-32. [PMID: 10909152 DOI: 10.1016/s0248-8663(00)89228-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Sporadic Alzheimer's disease is the most frequent form of dementia and appears to be associated with increasing age and certain genetic and environmental factors. Some studies have recently been published on potential protective factors. CURRENT KNOWLEDGE AND KEY POINTS Several genes appear to be involved; one of the most common is the ApoE4 allele on chromosome 19. The physiopathology is not elucidated, but recent studies have shown a protective effect for NSAIDs, estrogen, nutritional factors (vitamins E, B6 and B12) as well as some biochemical amino acids (homocysteine). FUTURE PROSPECTS AND PROJECTS Interventional studies are now in progress and some preventive approaches will soon be available.
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Affiliation(s)
- F Nourhashémi
- Service de médecine interne et de gérontologie clinique, hôpital Purpan-Casselardit, CHU, Toulouse, France
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530
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Bartus RT. On neurodegenerative diseases, models, and treatment strategies: lessons learned and lessons forgotten a generation following the cholinergic hypothesis. Exp Neurol 2000; 163:495-529. [PMID: 10833325 DOI: 10.1006/exnr.2000.7397] [Citation(s) in RCA: 552] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Life's Journey If life is indeed a journey, then poetry must be the map that reveals all its topographic possibilitiesellipsis while science is the compass that keeps us from getting lost. -R. T. Bartus, Simple Words for Complex Lives, (c) 1998 In the nearly 20 years since the cholinergic hypothesis was initially formulated, significant progress has been achieved. Initial palliative treatments for Alzheimer's disease (AD) have proven beneficial and have gained FDA approval, the use of animal models for studying AD and other neurodegenerative diseases has achieved wider acceptance, and important insight into the potential causes and pathogenic variables associated with various neurodegenerative diseases continues to increase. This paper reviews the current status of the cholinergic hypothesis in the context of continuing efforts to improve upon existing treatments for AD and explores the role that animal models might continue to play. Using the benefit of hindsight, particular emphasis is placed on an analysis of the approaches, strategies, and assumptions regarding animal models that proved useful in developing the initial treatments and those that did not. Additionally, contemporary issues of AD are discussed within the context of the cholinergic hypothesis, with particular attention given to how they may impact the further refinement of animal models, and the development of even more effective treatments. Finally, arguments are presented that, despite the deserved enthusiasm and optimism for identifying means of halting the pathogenesis of AD, a clear need for more effective palliative treatments will continue, long after successful pathogenic treatments are available. This review, therefore, focuses on issues and experiences intended to: (a) facilitate further development and use of animal models for AD and other neurodegenerative diseases, and (b) accelerate the identification of newer, even more effective treatments.
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Affiliation(s)
- R T Bartus
- Preclinical R&D, Alkermes, Inc., 64 Sidney Street, Cambridge, Massachusetts 02139, USA
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531
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Yaffe K, Haan M, Byers A, Tangen C, Kuller L. Estrogen use, APOE, and cognitive decline: evidence of gene-environment interaction. Neurology 2000; 54:1949-54. [PMID: 10822435 DOI: 10.1212/wnl.54.10.1949] [Citation(s) in RCA: 255] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVE APOE-epsilon4 increases the risk of cognitive decline, while elderly women who take estrogen may have less risk of cognitive decline. The authors sought to determine whether estrogen use modifies the association between APOE-epsilon4 and cognitive decline. METHOD - As part of the Cardiovascular Health Study, 3,393 Medicare-eligible women (> or =65 years) were randomly selected and recruited from Sacramento County, CA; Washington County, MD; Forsyth County, NC; and Pittsburgh, PA. Cognitive testing was administered annually; the authors studied the 2,716 women with cognitive testing on > or =2 visits. They analyzed change in score on the Modified Mini-Mental State Examination (3MS) as a function of estrogen use, APOE genotype, and baseline common and internal carotid artery wall thickening. RESULTS A total of 297 (11%) women were current estrogen users and 336 (12%) were past estrogen users. Over the 6-year average follow-up, baseline current users declined 1.5 points on the 3MS whereas never users declined 2.7 points (p = 0.023). Compared with epsilon4-negative women, epsilon4-positive women had a greater adjusted hazard ratio of cognitive impairment (3MS < 80), hazard risk [HR] = 1.47; 95% CI, 1.13 to 1.90. There was an interaction between estrogen use and epsilon4 presence (p = 0.037). Among epsilon4-negative women, current estrogen use reduced the risk of adjusted cognitive impairment compared with never users by almost half (HR = 0.59; 95% CI, 0.36 to 0.99), whereas, it did not reduce the risk among epsilon4-positive women (current use, HR = 1.33; 95% CI, 0.74 to 2.42). Compared with never use, current estrogen use was associated with less internal and common carotid wall thickening in epsilon4-negative women but not in epsilon4-positive women (p for interaction < 0.05 for both). Differences remained after adjusting for age, education, race, and stroke. CONCLUSIONS Estrogen use was associated with less cognitive decline among epsilon4-negative women but not epsilon4-positive women. Potential mechanisms, including carotid atherosclerosis, by which epsilon4 may interact with estrogen and cognition warrant further investigation.
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Affiliation(s)
- K Yaffe
- Departments of Psychiatry and Neurology and the Center on Aging, University of California, San Francisco,USA
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532
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Mattix H, Singh AK. Estrogen replacement therapy: implications for postmenopausal women with end-stage renal disease. Curr Opin Nephrol Hypertens 2000; 9:207-14. [PMID: 10847319 DOI: 10.1097/00041552-200005000-00001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Little information is available about either the potential beneficial or harmful effects of estrogen replacement therapy in postmenopausal women with end-stage renal disease. Although evidence supports a role for estrogen replacement therapy in postmenopausal women in the prevention of cardiovascular disease and bone loss, possible improvement in cognitive function, and the relief of menopausal symptoms, these conclusions may not be applicable to patients with end-stage renal disease, since these studies have generally excluded such women. This issue is of considerable importance since cardiovascular causes account for more than 50% of the all-cause mortality in patients with end-stage renal disease. However, estrogen replacement therapy may also have untoward effects in patients with the disease, including an increased risk of dialysis access thrombosis and potentially worsening coronary artery disease in postmenopausal patients. Furthermore, dosing of estrogens needs to be done carefully since renal excretion is important for the elimination of estrogen metabolites. Low dose or alternate day dosing in addition to monitoring estrogen levels may be warranted when prescribing estrogen replacement therapy to women with end-stage renal disease. In this review, it is our objective to analyze the evidence published in the literature so far and to weigh the risks and benefits of estrogen therapy in postmenopausal women with end-stage renal disease.
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Affiliation(s)
- H Mattix
- Renal Unit, Massachusetts General Hospital, Boston, USA
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533
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Morley JE, Unterman TG. Hormonal fountains of youth. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 2000; 135:364-6. [PMID: 10811049 DOI: 10.1067/mlc.2000.106454] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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534
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Abstract
INTRODUCTION Considered until recently as a biological fate, menopause has evolved within a decade into a major public health issue at stake. Such an evolution results from various factors that deserve an exhaustive critical approach because the situation is much more complex than it appears to be at first analysis. CURRENT KNOWLEDGE AND KEY POINTS 1) Ninety-five percent of the available epidemiological information relies on observation or cohort studies, such as case-control studies that do not allow any certitude in regard to therapy. 2) Chronic estrogen deficiency probably plays a pathogenic role in various symptoms or pathological conditions that are associated to menopause. 3) However, behind the paradigm of menopause, there is a whole psychosocial construct that classifies what remains a physiological condition within major risk factors, just as for the most serious chronic diseases. 4) Indeed, menopause cannot be considered as a well-characterized disease, and hormone replacement therapy is undeniably a complex therapeutic intervention that requires proper prescription and careful evaluation of the benefit:risk ratio. 5) While such a treatment is now considered as the gold standard for the prevention of post-menopausal osteoporosis, this does not hold true regarding cardiovascular diseases. 6) Although hormone replacement therapy may lead to the relief of various symptoms associated with menopause, it may also result in side-effects that extreme medication cannot prevent, especially since some of them are not fully known, particularly in the case of either long-term or very long-term treatments. FUTURE PROSPECTS AND PROJECTS A more rigorous evaluation of side-effects of hormone replacement therapy in the framework of long-term controlled trials is therefore clearly required. The indications of such a treatment should only rely on objective data and not on questionable studies or impressions at clinical examination.
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Affiliation(s)
- P Tellier
- Centre de médecine nucléaire de l'Artois, clinique Sainte-Catherine, Paris, France
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535
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Luoto R, Manolio T, Meilahn E, Bhadelia R, Furberg C, Cooper L, Kraut M. Estrogen replacement therapy and MRI-demonstrated cerebral infarcts, white matter changes, and brain atrophy in older women: the Cardiovascular Health Study. J Am Geriatr Soc 2000; 48:467-72. [PMID: 10811537 DOI: 10.1111/j.1532-5415.2000.tb04990.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVE We studied the relationship between the use of estrogen replacement therapy (ERT) and cerebral magnetic resonance imaging (MRI) abnormalities among older women. DESIGN A population-based prospective study (Cardiovascular Health Study). SETTING Four regions in the United States. PARTICIPANTS A total of 2133 (62.9% of the eligible) women aged 65 to 95 years (mean age 74.8), on whom MRI was performed in 1992-1994. MEASUREMENTS Presence of global brain atrophy, white matter changes, small infarct-like lesion (ILL) (<3 mm), MRI infarcts (> or =3 mm, mostly small and asymptomatic), and cognitive function as measured by Mini-Mental State Exam (MMSE), and by ERT use (current/past/never), adjusted for a number of socioeconomic, lifestyle, and reproductive covariates. RESULTS Current use of ERT was reported by 15% and past use by another 23% of participants; 35% of all women had MRI infarcts. The prevalence of MRI infarcts did not differ in current or past users from those who had never used ERT (nonusers). Bifrontal distance, the largest distance between frontal horns, and the size of ventricles were larger among current ERT users compared to past users or nonusers (P (trend) = .01), adjusted for all other covariates, but no dose-response relationship to current or past ERT use was found. Duration of estrogen use was not associated with any atrophy measure. Cortical atrophy measure, sulcal widening, or white matter disease did not differ significantly by ERT use or duration of use. Central measures of atrophy, bifrontal distance, and ventricular size were significantly associated with cognition as measured by MMSE. CONCLUSIONS Current ERT users had much more clinically significant central atrophy than nonusers, but the implications remained unclear.
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Affiliation(s)
- R Luoto
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
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536
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Duetz MS, Abel T, Meier C, Niemann S. Self-rated health, life satisfaction and personal characteristics of post-menopausal women under estrogen replacement therapy. Maturitas 2000; 35:71-9. [PMID: 10802403 DOI: 10.1016/s0378-5122(00)00104-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES To describe the prevalence of oestrogen replacement therapy (ERT)-use among post-menopausal women in relation with personal and socio-economic characteristics and to examine the association of ERT-use with self-rated health and selected aspects of life satisfaction. METHODS Population survey data were derived from a cohort study of 511 Bernese women, aged 55-65 years. Data were collected by means of telephone interviews. Overall prevalence of ERT-use, and selected associations with personal and socio-economic characteristics were investigated using descriptive statistical methods and logistic regression. The relations of ERT-use with five self-reported health measures were explored using Spearman's correlation coefficients. The associations of ERT-use with six dichotomous variables on satisfaction with various aspects of life were tested with chi-square tests in cross tabulations. RESULTS The overall prevalence of self reported ERT-use was 17.6%. ERT was more prevalent women younger than 61 years than in women in the older age group. Women with a body mass index (BMI) under 25 reported ERT-use significantly more frequently than women with higher BMI (OR=3.16, CI 1.87-5.34). ERT-use was more prevalent in women with relatively high education: OR=2.01, CI 1.18-4.00. The self-reported health measures and the satisfaction items were not significantly associated with ERT-use. CONCLUSIONS ERT-use among post-menopausal women was found to be associated with higher educational level and lower BMI. ERT-users did not report better health or life-satisfaction.
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Affiliation(s)
- M S Duetz
- Unit for Health Research, Departement of Social and Preventive Medicine, University of Bern, Niesenweg 6, 3012, Bern, Switzerland.
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537
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538
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539
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Abstract
Menopause, the permanent cessation of menstruation, is due to ovarian failure, which may lead to oestrogen deficiency diseases, particularly osteoporosis, cardiovascular disease and cerebrovascular disease. Mortality and morbidity caused by these conditions can be modified by using hormone replacement therapy, but the benefits of this therapy must be weighed against the increased risk of breast cancer and the symptomatic side-effects the treatment may cause. The combination of transdermal oestrogen and natural progesterone offers the most favourable risk-to-benefit profile.
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540
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Abstract
Osteoporosis is a disorder of decreased bone mass, microarchitectural deterioration, and fragility fractures. Osteoporosis is widespread and can affect people of all ethnic backgrounds and many older women and men. An essential element in preventing osteoporosis is the achievement of normal peak bone mass. Adequate nutrition, appropriate calcium and vitamin D intake, regular menstrual cycles and a well balanced exercise program of exercise are essential elements in achieving peak bone mass. At menopause women undergo accelerated bone loss. Thereafter, women and men gradually lose bone mass. A loss of one standard deviation give rise to an enhanced twofold risk of spine fractures or a 2.5 risk of hip fracture. Bone mass is determined by dual energy x-ray absorptiometry, quantitative computed tomography scan, and a peripheral ultrasound. Dual energy x-ray absorptiometry has outstanding precision (within 1% to 2%), and has the ability to show the efficacy of drug intervention. Peripheral measurements may identify osteoporosis but only have a 70% correlation with hip and spine bone mass. Dual energy x-ray absorptiometry determines bone mass in a patient but the bone collagen breakdown products (N-telopeptide crosslinks) establish the current rate of bone loss. Major risk factors leading to fragility fracture include low body weight, history of fracture, family history of osteoporosis, and smoking. All individuals should ingest adequate calcium and vitamin D, exercise, and prevent falls. Women with low bone mass, high urinary bone collagen breakdown products, and/or major risk factors should consider hormone replacement therapy or a selective estrogen receptor modulator (Evista), calcitonin and bisphosphonates (alendronate). These agents successfully increase bone mass and limit fracture risk. Men at risk for fragility fractures respond similarly as women to alendronate and calcitonin. Although vertebral compression fractures can occur spontaneously, hip fractures are attributable to low bone mass coupled with a fall. Hence, fall prevention programs in addition to medical treatment are critical in the prevention of fragility fractures.
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Affiliation(s)
- J M Lane
- Department of Orthopaedic Surgery, Weill Medical College of Cornell University, Hospital for Special Surgery, New York, NY, USA
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541
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Affiliation(s)
- K P Jones
- Department of Obstetrics and Gynecology, University of Utah Health Sciences Center, Salt Lake City 84132, USA
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542
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543
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Abstract
This review outlines the basic principles of a novel interrupted progestin HRT regimen in which estrogen is administered continuously, and progestin is given in a 3-days on, 3-days off pulsed fashion. The rationale for this regimen is to prevent receptor down-regulation and allow increased estrogen and progestin sensitivity during the progestin-free periods. Background information is provided including the reasons for poor patient acceptance of HRT, and the concerns of the potential association of HRT with breast and endometrial cancer. Experimental studies in the rat are described which provide evidence in support of the rationale for the interrupted progestin regimen. Clinically, two pilot studies examining symptom control, bleeding rates and safety of the interrupted progestin regimen, as well as preliminary results of a third study examining the usefulness of this regimen for addback therapy in GnRH agonist treated patients, are outlined. The preliminary results of phase III trials are presented. These clinical studies all demonstrated good symptom control, low bleeding rates, endometrial protection, and excellent patient acceptance. The combination of continuous estrogen with interrupted progestin appears to result in increased sensitivity to estrogen and progestin in estrogen responsive tissues. As a result, lower doses of estrogen and progestin may be used for HRT with good biological effects. Further clinical studies, preferably in prospective randomized trials, are required to demonstrate an advantage of this new regimen compared to continuous combined HRT.
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Affiliation(s)
- R F Casper
- Department of Obstetrics and Gynecology, The University of Toronto, Ont., Canada.
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544
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Nourhashemi F, Gillette-Guyonnet S, Andrieu S, Ghisolfi A, Ousset PJ, Grandjean H, Grand A, Pous J, Vellas B, Albarede JL. Alzheimer disease: protective factors. Am J Clin Nutr 2000; 71:643S-649S. [PMID: 10681273 DOI: 10.1093/ajcn/71.2.643s] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Approximately 6-8% of all persons aged >65 y have Alzheimer disease and the prevalence of the disease is increasing. Any intervention strategy aimed at decreasing risks or delaying the onset of the disease will therefore have a substantial effect on health care costs. Nutrition seems to be one of the factors that may play a protective role in Alzheimer disease. Many studies suggest that oxidative stress and the accumulation of free radicals are involved in the pathophysiology of the disease. Several studies have shown the existence of a correlation between cognitive skills and the serum concentrations of folate, vitamin B-12, vitamin B-6, and, more recently, homocysteine. However, nutritional factors have to be studied not alone but with the other factors related to Alzheimer disease: genetics, estrogen, antiinflammatory drug use, and socioeconomic variables. The objective of this article was to review recent studies in this field.
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Affiliation(s)
- F Nourhashemi
- Department of Internal Medicine and Clinical Gerontology, University Hospital, Toulouse, France
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545
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546
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O'Hara R, Mumenthaler MS, Yesavage JA. Update on Alzheimer's disease: recent findings and treatments. West J Med 2000; 172:115-20. [PMID: 10693374 PMCID: PMC1070770 DOI: 10.1136/ewjm.172.2.115] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- R O'Hara
- Department of Psychiatry and Behavioral Sciences, Stanford University, CA 94305-5550, USA.
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547
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Morrison MF, Redei E, TenHave T, Parmelee P, Boyce AA, Sinha PS, Katz IR. Dehydroepiandrosterone sulfate and psychiatric measures in a frail, elderly residential care population. Biol Psychiatry 2000; 47:144-50. [PMID: 10664831 DOI: 10.1016/s0006-3223(99)00099-2] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Previous reports have found low levels of dehydroepiandrosterone sulfate (DHEA-S) in association with physical illness, and with frailty in the elderly. In a preliminary study, we also found low DHEA-S associated with increased disability and number of pain sites. However, we found the opposite relationship between DHEA-S and cognitive impairment. Therefore, we conducted a study of a second sample to confirm this unexpected finding and the expected inverse correlations between DHEA-S levels and increased disability and number of pain sites. METHODS Psychiatric symptoms and disorders were correlated with DHEA-S and related steroid levels in a second convenience sample in the nursing home population. RESULTS This sample confirmed the previous finding of a positive association of cognitive impairment with higher DHEA-S levels but the inverse association of DHEA-S levels with the numbers of pain sensations did not reach statistical significance. Cognitive impairment was also positively associated with higher dehydroepiandrosterone (DHEA) and estradiol levels (women only). Cortisol levels were inversely associated with depressive symptoms. CONCLUSIONS The anomalous positive correlation between cognitive dysfunction and DHEA-S levels, and the inverse correlation between cortisol levels and depressive symptoms, suggests that the relationships between psychiatric symptomatology and levels of steroids that are part of the hypothalamic-pituitary adrenal axis are different in the frail elderly population from that of younger and heartier populations.
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Affiliation(s)
- M F Morrison
- Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia 19104-4283, USA
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548
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Windisch M. Approach towards an integrative drug treatment of Alzheimer's disease. JOURNAL OF NEURAL TRANSMISSION. SUPPLEMENTUM 2000; 59:301-13. [PMID: 10961442 DOI: 10.1007/978-3-7091-6781-6_32] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
At present pharmacotherapy of Alzheimer's disease (AD) is limited to acetylcholinesterase inhibitors. These drugs produce small, but consistent improvements of memory and global function, some are also positively influencing activities of daily living. This therapeutic approach neglects the complexity of AD and the fact that most of the degenerating neurons are not cholinergic. Acetylcholinesterase inhibitors are symptomatic drugs, with no influence on disease progression. There is a need for disease modifying compounds, or preventive drugs. Data are indicating that vitamin E has some ability to influence the disease progression. The potency of non-steroidal anti-inflammatory drugs (NSAIDs) or estrogen as preventive agents has to be explored further in prospective clinical studies. The initial hope in the use of naturally occurring neurotrophic factors, like nerve growth factor, to rescue cholinergic neurons from degeneration and to restore cognitive function has been disappointed in first, small clinical studies. The peptidergic drug Cerebrolysin exhibiting neurotrophic stimulation, neuroimmunotrophic regulation and induction of BBB glucose transporter expression, might be able to address the pathological changes of AD at different levels simultaneously. In addition to an impressive preclinical database, results from 3 placebo-controlled, double-blind studies demonstrate significant improvements of cognitive performance, global function and activities of daily living in AD patients. In all studies persisting improvements, up to 6 months after drug withdrawal, indicate a powerful disease modifying activity.
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Affiliation(s)
- M Windisch
- JSW-Research Forschungslabor Graz, Austria
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549
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The effects of long-term ovariectomy and estrogen replacement therapy on learning and memory in monkeys (Macaca fascicularis). Behav Neurosci 2000. [DOI: 10.1037/0735-7044.114.6.1078] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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550
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Abstract
Gender-based differences in the prevalence, presentation, and treatment of coronary heart disease (CHD) defines an important area of controversy and research. Gender-based differences include age at onset of CHD, typical presentation of CHD symptoms, relative importance of coronary risk factors, and the potential relationship of ovarian function and estrogen status to the development of CHD. The American Heart Association reported in 1998 that the leading cause of death for American women is cardiovascular disease, with CHD responsible for the majority of total deaths. This article discusses the implication of elevated blood lipids in women. Special emphasis is placed on the role of hormone replacement therapy, an issue unique to women.
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Affiliation(s)
- K Berra
- Stanford Center for Research in Disease Prevention, Stanford University Medical School, Palo Alto, California, USA
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