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Pregnenolone 孕烯醇酮 其他通用名稱：無 科學/醫學名稱：3-羥基孕-5-en-20-一 描述 孕烯醇酮是人體產生的一種類固醇，是其他類固醇激素的前體，例如黃體酮、DHEA（參見DHEA）、鹽皮質激素（調節電解質平衡）、皮質類固醇（影響發炎和新陳代謝）、雌激素和雄激素。 概述 現有的科學證據並不支持孕烯醇酮有助於治療關節炎、多發性硬化症和癌症等疾病的說法。 一些動物研究顯示孕烯醇酮可能有助於改善記憶力，但尚未報告人類研究。 如何推廣使用？ 孕烯醇酮主要作為一種替代療法來推廣，可以提高記憶力和警覺性，並減輕壓力、憂鬱和疲勞。 一些推廣者聲稱孕烯醇酮也有助於治療多種其他疾病，如關節炎、癌症、骨質疏鬆症、肥胖症、多發性硬化症、經前症候群和更年期。 它涉及什麼？ 孕烯醇酮補充劑以片劑、膠囊和外用乳膏的形式出售。 儘管有 5 至 50 毫克的規格，但沒有標準劑量。 它背後的歷史是什麼？ 孕烯醇酮是 20 世紀 40 年代多項動物和人類研究的主題。 有些人提出了對關節炎的潛在臨床用途以及透過減輕壓力來提高表現。 隨後的研究表明，孕烯醇酮是人體產生所有類固醇激素的前驅物。 隨著研究人員對這些其他荷爾蒙了解更多，對孕烯醇酮作為治療方法的興趣下降了。 例如，皮質醇（另一種由前烯醇酮製成的荷爾蒙）可用於治療關節炎發炎和其他疾病，醫生認為皮質醇治療比使用前烯醇酮治療更有意義，後者不僅被身體用來產生皮質醇，也會產生雌激素、雄性激素和其他激素。 天然類固醇激素的化學修飾或合成形式已被開發出來並在臨床試驗中作為藥物進行測試，那些被發現更有效且具有更具體效果的藥物現已成為臨床醫學的首選。 最近，一些替代療法從業者對孕烯醇酮作為一種治療方法的興趣增加，許多網站目前提倡將其用於關節炎、阿茲海默症、運動訓練和癌症。 證據是什麼？ 一些推廣者聲稱孕烯醇酮也有助於治療多種其他疾病，如關節炎、癌症、骨質疏鬆症、肥胖症、多發性硬化症、經前症候群和更年期。 現有的臨床證據並不支持這些說法。 對小鼠的研究表明記憶力可能會增強，但尚不清楚這種益處是否會發生在人類身上。 20 世紀 40 年代進行的臨床研究表明，孕烯醇酮可能會增強注意力以及身心表現。 儘管 1997 年作為摘要（但不是完整文章）報告的一項小型研究發現對力量、平衡或記憶沒有影響，但這些研究尚未用現代臨床研究方法進行複製。 一些動物研究表明孕烯醇酮可能有助於改善記憶力，但現有的同行評審醫學文獻中尚未報告人體研究來證實這一點。 天然類固醇激素的化學修飾或合成形式已被開發出來並在臨床試驗中作為藥物進行測試，那些被發現更有效且具有更具體效果的藥物現已成為臨床醫學的首選。 最近，一些替代療法從業者對孕烯醇酮作為一種治療方法的興趣增加，許多網站目前提倡將其用於關節炎、阿茲海默症、運動訓練和癌症。
人們對補充劑的安全性或長期使用的影響知之甚少。 一些針對癌細胞和動物的實驗室研究表明，孕烯醇酮可能會刺激荷爾蒙反應性癌症（例如前列腺癌和乳腺癌）的生長。 身體使用孕烯醇酮來製造類固醇激素，例如 DHEA 和睪固酮。 高劑量可能會導致女性出現攻擊性、易怒、睡眠困難以及身體或臉部毛髮生長。 它還可能會停止月經並降低高密度脂蛋白或「好」膽固醇的水平，這可能會增加心臟病的風險。 其他可能的副作用包括痤瘡、心律問題、肝臟問題、頭皮脫髮和油性皮膚。 儘管一些研究表明它可能會幹擾某些安眠藥物或鎮靜藥物（苯二氮平類藥物）的作用，但人們對藥物交互作用知之甚少。 請務必告訴您的醫生和藥劑師您正在服用的任何補充劑或草藥。 懷孕或哺乳的婦女不應使用孕烯醇酮。 僅依賴這種類型的治療並避免或延遲傳統的癌症醫療護理可能會產生嚴重的健康後果。 其他資源 來自美國癌症協會的更多信息 以下有關補充和替代療法的資訊也可能對您有所幫助。 這些資料可以在我們的網站 (www.cancer.org) 上找到或透過我們的免費電話 (1-800-ACS-2345) 訂購。 使用補充和替代方法的指南 如何知道什麼是安全的：選擇和使用膳食補充劑 ACS 關於癌症治療補充和替代方法的操作聲明 癌症治療的補充和替代方法 安慰劑效應 了解治療癌症的新方法 了解預防癌症的新方法 參考 Flood JF，Morley JE，Roberts E。孕烯醇酮和代謝衍生的類固醇對雄性小鼠的記憶增強作用。 美國國家科學院院刊，1992；89：1567-1571。 Grigoryev DN、Long BJ、Njar VC、Brodie AH。 孕烯醇酮透過突變的雄性激素受體刺激 LNCaP 前列腺癌細胞生長。 J 類固醇生物化學分子生物學雜誌。 2000；75：1-10。 Meieran SE、Reus VI、Webster R、Shafton R、Wolkowitz OM。 孕烯醇酮對正常人的慢性影響：苯二氮平類藥物引起的鎮靜作用減弱。 精神神經內分泌學。 2004；29：486-500。 PDR健康。 孕烯醇酮。 請造訪：www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/pre_0211.shtml，2008 年 6 月 11 日。 Roberts E. Pregneolone－從 Selye 到阿茲海默症以及 GABAA 受體上硫酸孕烯醇酮結合位點的模型。 生物化學藥理學。 1995；49：1-16。 Sih R、Morley JE、Kaiser FE、Herning M。孕烯醇酮對老化的影響。 J 調查醫學。 1997；45：348A。 塔里克·SH、卡邁勒·H、莫利·JE。 脫氫表雄酮和孕烯醇酮。 請參閱：Meikle AW，編輯。 臨床實務中的內分泌替代療法。 新澤西州托托瓦； 哈馬納出版社； 2003 年：307-368。 注意：此資訊可能不涵蓋所有可能的聲明、用途、行動、預防措施、副作用或交互作用。 它並非醫療建議，也不應取代您向熟悉您的醫療狀況的醫生諮詢。 最後一次醫療審查：2008 年 11 月 1 日 最後修訂日期：2008 年 11 月 1 日 Other common name(s): none Scientific/medical name(s): 3-hydroxypregn-5-en-20-one Description Pregnenolone is a steroid the body makes as a precursor to other steroid hormones, such as progesterone, DHEA (see DHEA), mineralocorticoids (which regulate electrolyte balance), corticosteroids (which influence inflammation and metabolism), estrogens, and androgens. Overview Available scientific evidence does not support claims that pregnenolone can help treat conditions such as arthritis, multiple sclerosis, and cancer. Some research in animals has suggested that pregnenolone may help improve memory, but no research in humans has been reported. How is it promoted for use? Pregnenolone is mainly promoted as an alternative treatment that improves memory and alertness and reduces stress, depression, and fatigue. Some promoters claim pregnenolone also helps treat a variety of other conditions such as arthritis, cancer, osteoporosis, obesity, multiple sclerosis, premenstrual syndrome, and menopause. What does it involve? Pregnenolone supplements are sold in tablet and capsule form and as a topical cream. There is no standard dose, although it is available in strengths ranging from 5 to 50 milligrams. What is the history behind it? Pregnenolone was the subject of several animal and human studies during the 1940s. Some suggested potential clinical use for arthritis as well as for improving performance by reducing stress. Subsequent research demonstrated that pregnenolone is the precursor used by the body in producing all steroid hormones. As researchers learned more about these other hormones, interest in pregnenolone as a treatment decreased. For example, cortisol (another hormone made from pregenolone) is useful in treating inflammation of arthritis and other diseases, and doctors felt treatment with cortisol made more sense than treatment with pregenolone, which was used by the body in producing not only cortisol but also estrogens, androgens, and other hormones. Chemically modified or synthetic versions of natural steroid hormones have been developed and tested as drugs in clinical trials, and those found to be more potent and to have more specific effects are now preferred in clinical medicine. Interest in pregnenolone as a treatment has increased recently among some alternative practitioners, and a number of websites currently advocate its use for arthritis, Alzheimer disease, athletic training, and cancer. What is the evidence? Some promoters claim pregnenolone also helps treat a variety of other conditions such as arthritis, cancer, osteoporosis, obesity, multiple sclerosis, premenstrual syndrome, and menopause. Available clinical evidence does not support these claims. Studies in mice suggest possible enhancement of memory, but it is unclear whether this benefit would occur in humans. Clinical studies done during the 1940s suggested that pregnenolone might enhance attention and physical and mental performance. These studies have not been replicated with modern clinical research methods, although a small study reported in 1997 as an abstract (but not a full article) found no effect on strength, balance, or memory. Some animal studies have suggested that pregnenolone may help improve memory, but no human studies have been reported in the available peer-reviewed medical literature to confirm this. Are there any possible problems or complications? Very little is known about the safety of the supplements or the effects of long-term use. Some laboratory studies in cancer cells and animals have suggested that pregnenolone may stimulate the growth of hormone-responsive cancers such as prostate and breast cancer. The body uses pregnenolone to make steroid hormones such as DHEA and testosterone. High doses may cause aggressiveness, irritability, trouble sleeping, and the growth of body or facial hair on women. It also may stop menstruation and lower the levels of HDL, or "good," cholesterol, which could raise the risk of heart disease. Other possible side effects include acne, heart rhythm problems, liver problems, loss of hair from the scalp, and oily skin. Little is known about drug interactions, although some studies suggest it may interfere with the action of certain sleeping medicines or calming medicines (benzodiazepines). Always tell your doctor and pharmacist about any supplements or herbs you are taking. Women who are pregnant or breastfeeding should not use pregnenolone. Relying on this type of treatment alone and avoiding or delaying conventional medical care for cancer may have serious health consequences. Additional Resources More information from your American Cancer Society The following information on complementary and alternative therapies may also be helpful to you. These materials may be found on our Web site (www.cancer.org) or ordered from our toll-free number (1-800-ACS-2345). Guidelines for Using Complementary and Alternative Methods How to Know What Is Safe: Choosing and Using Dietary Supplements The ACS Operational Statement on Complementary and Alternative Methods of Cancer Management Complementary and Alternative Methods for Cancer Management Learning About New Ways to Treat Cancer Learning About New Ways to Prevent Cancer References Flood JF, Morley JE, Roberts E. Memory-enhancing effects in male mice of pregnenolone and steroids metabolically derived from it. Proc Natl Acad Sci U S A. 1992;89:1567-1571. Grigoryev DN, Long BJ, Njar VC, Brodie AH. Pregnenolone stimulates LNCaP prostate cancer cell growth via the mutated androgen receptor. J Steroid Biochem Mol Biol. 2000;75:1-10. Meieran SE, Reus VI, Webster R, Shafton R, Wolkowitz OM. Chronic pregnenolone effects in normal humans: attenuation of benzodiazepine-induced sedation. Psychoneuroendocrinology. 2004;29:486-500. PDRhealth. Pregnenolone. Accessed at: www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/pre_0211.shtml on June 11, 2008. Roberts E. Pregneolone--from Selye to Alzheimer and a model of the pregnenolone sulfate binding site on the GABAA receptor. Biochem Pharmacol. 1995;49:1-16. Sih R, Morley JE, Kaiser FE, Herning M. Effects of pregnenolone on aging. J Investig Med. 1997;45:348A. Tariq SH, Kamel H, Morley JE. Dehydroepiandrosterone and pregnenolone. In: Meikle AW, ed. Endocrine Replacement Therapy in Clinical Practice. Totowa, NJ; Humana Press; 2003: 307-368. Note: This information may not cover all possible claims, uses, actions, precautions, side effects or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for consultation with your doctor, who is familiar with your medical situation. Last Medical Review: 11/01/2008 |
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