Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0086543 (cataract)
 29,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A detailed study was initiated to investigate thoroughly the possibility that any significant ophthalmologic changes might have occurred in patients using oral contraceptives (OCs) for varying periods. There were 212 patients and 50 control patients who were selected at random, 1/2 from private ophthalmology practice and 1/2 from Planned Parenthood Centers in Los Angeles. During eye examinations, the visual acuity and tonometric measurements were recorded. After pupillary dilation, slit-lamp and funduscopic examinations were performed. Among the compounds being taken by patients in this program were norethynodrel-mestranol combinations, norethindrone-mestranol preparations, medroxyprogesterone acetate with ethinyl estradiol, norethindrone acetate-ethinyl estradiol, and norethindrone-mestranol sequential. None of the control patients were using any medication similar to that of the patients under study, and all were given the same examination by the same opthalmologist. A substantial percentage of patients using OCs had some degree of ocular pathology. Much of this was of an insignificant variety and could in no way be related to OC use. In 212 patients (424 eyes) there were 6 instances in which there were potentially progressive lens conditions of unknown cause. None was of the classic complicated or toxic types of cataract. In the small group of control patients, 4% of the eyes had subcapsular vacuoles of the lens. In the contraceptive-treated group, there were only approximately 1.5% showing similar potentially progressive lens pathology. There was 1 case of potential galucoma in the control group and 1 in the contraceptive-treated group. No papilledema was observed in this series.
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PMID:Ophthalmologic findings in patients using oral contraception. 590 Oct 10

A comprehensive review of the ophthalmic literature on cataracts during the past year is presented. Topics covered include new epidemiologic associations, diabetic cataracts, and syndromes involving cataracts. Data from the Beaver Dam Eye Study suggest the presence of a recessive gene for nuclear sclerosis. Estrogen exposure may decrease the risk of nuclear sclerosis. The effects of amiodarone, propranolol, and lovastatin on the lens are discussed. Electron microscopy studies have furthered our understanding of diabetic cataracts and the rare Christmas tree cataract. Two new studies support the adverse effect of extracapsular cataract extraction on diabetic retinopathy. New associations between neurofibromatosis 2 and the lens will aid in the diagnosis of this condition. Other ocular and systemic syndromes are discussed.
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PMID:Cataracts in systemic diseases and syndromes. 1015 Aug 40

HRT (Hormone Replacement Therapy) is the administration of low estrogen preparation to post-menopausal women. This therapy is considered to be effective in protecting various human tissues from aging processes, which are also related to the decrease in endogenous estrogen level. Estrogen receptors were found in many human tissues and organs, including the eye. Therefore HRT may also have a beneficial effect on the eye and its adnexa. This review presents the ever growing data accumulated over the past years concerning the beneficial effects of HRT on various eye pathologies. It was found that HRT may relieve dry eye symptoms in post-menopausal women, may decrease the intraocular pressure and may delay cataract formation in treated women. In the retina, HRT may play a role in decreasing the incidence of Aging Macular Degeneration (AMD) in post-menopausal women.
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PMID:[The effects of hormone replacement therapy (HRT) on the human eye]. 1194 25

Cataract is the leading cause of visual impairment in older adults in the world. Age-related lens opacities are common and are frequent causes of loss of vision. The incidence of cataract increases significantly with increasing age in women only. The onset coincides with estrogen deficiency that occurs after menopause. Hormone replacement therapy has proven beneficial to selected postmenopausal women. Estrogen effects on biological system are modulated via the estrogen receptors (ER) and/or estrogen metabolites. Although ER have been detected in ocular tissue, whether ER polymorphism is related to cataract is not known at present. The polymorphisms of estrogen metabolizing enzymes are also related to the serum concentration and activity of estrogen. Polymorphism such as cytochrome P450c17 (A2/A2), cytochrome P450c1A (vt/vt) will result in increased formation of catechol estrogen, while people with catechol-O-methyltransferase (COMT) polymorphism COMT (L/L) will have decreased metabolism of catechol estrogen and decreased level of methoxyestradiol. COMT was also involved in tamoxifen metabolism which may further decrease the activity of COMT in breast cancer patients treated with tamoxifen. It is known that a 4-7% increase in cataract was found in tamoxifen-treated breast cancer patients than non-user. The 7.0% COMT (L/L) genotype in general population corresponded well with the 4-7% of cataract formation in tamoxifen-treated breast cancer patients. Our hypothesis is that breast cancer patients with COMT (L/L) genotype may be at increased risk of cataract formation after tamoxifen treatment.
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PMID:Polymorphism of estrogen metabolism genes and cataract. 1528 75

A number of epidemiologic studies have demonstrated that senior age at menarche and junior age at menopause are associated with an increased incidence of cataract, and that endogenous estrogen or postmenopausal hormone replacement therapy (HRT) may prevent cataract development. The molecular mechanisms behind this phenomenon are largely undetermined. Estrogen confers protection against cataract through antioxidative impairment, maintains normal function of lenticular membrane, TGF-beta mediated and estrogen receptor mediated effects. The research of these effects and its interactions may lead to a better understanding of the protective mechanism of estrogen and also provide a new thought for treatment and prevention of cataract.
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PMID:[Preventive effect of estrogen on cataract development]. 1716 24

Cataractogenesis is a complication of radiotherapy when the eye is included in the treatment field. Low doses of densely ionizing space radiation may also result in an increased risk of cataracts in astronauts. We previously reported that estrogen (17-beta-estradiol), when administered to ovariectomized rats commencing 1 week before gamma irradiation of the eye and continuously thereafter, results in a significant increase in the rate and incidence of cataract formation and a decreased latent period compared to an ovariectomized control group. We therefore concluded that estrogen accelerates progression of radiation-induced opacification. We now show that estrogen, if administered continuously, but commencing after irradiation, protects against radiation cataractogenesis. Both the rate of progression and incidence of cataracts were greatly reduced in ovariectomized rats that received estrogen treatment after irradiation compared to ovariectomized rats. As in our previous study, estradiol administered 1 week prior to irradiation at the time of ovariectomy and throughout the period of observation produced an enhanced rate of cataract progression. Estrogen administered for only 1 week prior to irradiation had no effect on the rate of progression but resulted in a slight reduction in the incidence. We conclude that estrogen may enhance or protect against radiation cataractogenesis, depending on when it is administered relative to the time of irradiation, and may differentially modulate the initiation and progression phases of cataractogenesis. These data have important implications for astronauts and radiotherapy patients.
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PMID:Estrogen protects against radiation-induced cataractogenesis. 1913 41

Age-related macular degeneration (AMD) is a multifactorial eye disease that is associated with aging, family history, smoking, obesity, cataract surgery, arteriosclerosis, hypertension, hypercholesterolemia and unhealthy diet. Gender has commonly been classified as a weak or inconsistent risk factor for AMD. This disease is characterized by degeneration of retinal pigment epithelial (RPE) cells, Bruch's membrane, and choriocapillaris, which secondarily lead to damage and death of photoreceptor cells and central visual loss. Pathogenesis of AMD involves constant oxidative stress, chronic inflammation, and increased accumulation of lipofuscin and drusen. Estrogen has both anti-oxidative and anti-inflammatory capacity and it regulates signaling pathways that are involved in the pathogenesis of AMD. In this review, we discuss potential cellular signaling targets of estrogen in retinal cells and AMD pathology.
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PMID:Estrogen signalling in the pathogenesis of age-related macular degeneration. 2491 83