Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042755 (masculinization)
 2,562 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 60-year-old woman with a progressive virilization for about 5 yr developed diabetes mellitus with elevated insulin levels (fasting insulinemia ranging 32.4-45.8 microU/ml). The marked increase of plasma testosterone (total 5.7-8.2 ng/ml; free 11.5 pg/ml) and other endocrine markers clearly indicated the ovarian origin of hyperandrogenism. Pelvic ultrasonography, computerized axial tomography, and direct examination of ovaries during laparotomy, showed no evidence of neoplasia. Microscopic examination and immunocytochemical investigations confirmed the diagnosis of hyperthecosis. After oophorectomy and regression of hyperandrogenism, fasting and postprandial blood glucose concentrations normalized in spite of persistently elevated levels of insulinemia (fasting values ranging 32.0-61.0 microU/ml). The present case suggests that pathological increase of testosterone can interfere with insulin-glucose balance impairing the peripheral sensitivity to insulin.
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PMID:Reduction of insulin resistance after correction of nonneoplastic ovarian virilization. 851 85

Current therapeutic approaches to postmenopausal bone loss or established osteoporosis vary widely among the different regions of the world. Because no treatment of osteoporosis has unequivocally demonstrated full prevention of the appearance or the recurrence of axial or peripheral fractures so far, many investigational compounds are being developed. Anabolic steroids act mainly as inhibitors of bone resorption with very few, if any, effects on bone formation. Because of the high occurrence of signs of virilization and the weak effects on bone structure, the risk/benefit ratio in osteoporosis should be considered at least problematic. If ongoing large-scale trials confirm the expected benefits of estrogen antagonist/agonists on the skeleton and confirm no cardiovascular risk to postmenopausal women with optimal uterine safety, these substances are likely to become the most prominent alternative to hormonal replacement therapy after the menopause. Additional studies are requested to evaluate the potential benefit of growth hormone or insulin-like growth factors in treatment of osteoporosis. Ipriflavone acts predominantly as an inhibitor of bone resorption. To confirm the efficacy of ipriflavone on the prevention of vertebral fractures and its effects on bone mineral density in women with postmenopausal established osteoporosis, a large multicentric European study is being conducted. Treatment with parathyroid peptides induces a significant gain in bone mass, mainly in the axial skeleton. Long-term studies that compare peptides, doses, and regimes are needed to better understand the exact position of parathyroid peptides as treatment of osteoporosis. Prolonged administration of strontium to postmenopausal osteoporotic women resulted in a decoupling between bone resorption and formation that yielded a significant increase in the lumbar spine bone mineral density of treated subjects. In the view of these promising results and of the excellent tolerance of strontium during preliminary trials, additional investigations of this compound in prevention and treatment of osteoporosis should be promptly initiated. Several other compounds have been punctually suggested for treatment of osteoporosis or are at very early stages of development. Finally, besides pharmacologic approaches to the treatment of osteoporosis, hip fractures may also be reduced by the use of hip protectors.
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PMID:Miscellaneous and experimental agents. 900 Nov 64

The cardinal clinical features of PCOS are hirsutism and menstrual irregularity from anovulation. Obesity occurs in approximately 50% of hyperandrogenic anovulatory women, some of whom also have non-insulin-dependent diabetes mellitus. Underlying these clinical findings are several biochemical abnormalities, including LH hypersecretion, hyperandrogenism, acyclic estrogen production, decreased SHBG capacity, and hyperinsulinemia, all of which contribute to increased ovarian production of androgens, particularly T. A fundamental mechanism of ovarian hyperandrogenism in PCOS is LH hypersecretion. Whether the central nervous system is a possible locus for initiating LH hypersecretion remains unclear, because exaggerated LH secretion is temporarily reversed by induced ovulatory cycles or physiologic luteal concentrations of progesterone. On the other hand, desynchronization of pulsatile LH secretion from sleep in girls with PCOS and an exaggerated (e.g., masculinized) early LH response to GnRHa testing in women with hyperandrogenic anovulation and congenital adrenal virilizing disorders suggest that events occurring before puberty, perhaps during fetal life, may irreversibly alter neuroendocrine function. Hyperinsulinemia from insulin resistance is an important regulatory mechanism governing ovarian hyperandrogenism. Hyperinsulinemia in hyperandrogenic anovulatory women potentiates ovarian hyperandrogenism by enhancing LH secretion; potentiating 17-hydroxylase and, to a lesser extent, 17,20-lyase activity; and suppressing SHBG capacity. It is a key component of hyperandrogenic anovulation caused by a type of insulin resistance that in independent and additive to that of obesity alone. Although the mechanisms governing insulin action on ovarian steroidogenesis are unknown, abnormalities of intracellular insulin signaling or cytochrome P450c 17[alpha] activity may render the 17-hydroxylase/17,20-lyase enzyme complex more sensitive to insulin. Hyperinsulinemia in hyperandrogenic anovulatory women is accompanied by upper-body obesity characterized by an increased amount of abdominal fat. Upper-body obesity is an important independent risk factor for CVD and diabetes. Although genetic and environmental factors affect fat distribution, sex steroids, particularly androgens, regulate lipid metabolism, suggesting yet another link between the hormonal and metabolic abnormalities of hyperandrogenic anovulation. A careful history and physical examination guide the extent of diagnostic testing. Slowly progressive hirsutism with anovulation of peripubertal onset usually reflects hyperandrogenic anovulation. This type of clinical presentation requires an evaluation to rule out other endocrinopathies (e.g., virilizing tumors, adult-onset CAH, hyperprolactinemia, and Cushing's syndrome). Virilization or severe rapidly progressive hirsutism requires immediate investigation to rule out a possible virilizing tumor. The ultimate goals of therapy for hyperandrogenic anovulatory women are to normalize the endometrium, antagonize androgen action at target tissues, reduce insulin resistance, and correct anovulation, if necessary.
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PMID:Polycystic ovary syndrome. 942 64

The goals of this presentation are to review the essential roles of aromatase, estrogens and the estrogen receptor in pubertal growth. Estrogen deficiency due to mutations in the aromatase gene (CYP19) and estrogen resistance due to disruptive mutations in the estrogen receptor gene have no effect on normal male sexual maturation in puberty. However, they lead to absence of the pubertal growth spurt, delayed bone maturation, unfused epiphyses, continued growth into adulthood and very tall adult stature in both sexes. Gonadotropin and androgen levels are elevated in patients with either estrogen deficiency (aromatase deficiency) or estrogen resistance (estrogen receptor mutation). Glucose intolerance, hyperinsulinemia and lipid abnormalities are also present. Skeletal integrity is compromised. Increased bone turnover, reduced bone mineral density and osteoporosis develop in both sexes. Sexual orientation is appropriate in males and females. In females, aromatase deficiency in the ovary causes pubertal virilization and multicystic ovaries because of elevated gonadotropins and androgens. Simultaneously, secondary sexual maturation fails to occur. Placental aromatase deficiency results in virilization of the mother and her female fetus because of the accumulation of potent androgens which are not converted to estrogens. The male fetus has normal genitalia. In conclusion, estrogens are essential for normal female secondary sexual maturation, bone maturation, epiphyseal fusion, pubertal growth spurt and achievement of normal bone mineral mass. Estrogens also influence insulin sensitivity and lipid homeostasis. However, estrogens do not appear to be essential for fetal survival, placental growth, or female sexual differentiation.
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PMID:Pediatric endocrinology update: an overview. The essential roles of estrogens in pubertal growth, epiphyseal fusion and bone turnover: lessons from mutations in the genes for aromatase and the estrogen receptor. 955 63

The fundamental clinical features of PCOS include hirsutism and menstrual irregularities from the time of menarche. Obesity is present in approximately 50% of these patients, some of whom also carry a diagnosis of NIDDM. The biochemical abnormalities associated with the clinical picture include LH hypersecretion, hyperandrogenism, acyclic estrogen production, subnormal SHBG levels, and hyperinsulinemia. Hirsutism usually progresses slowly in patients with PCOS; however, the clinical presentation can resemble virilizing tumors, late-onset CAH, or Cushing syndrome. Virilization or rapidly progressive hirsutism requires immediate investigation to rule out a virilizing tumor. Goals of therapy for teenage patients include decreasing levels of bioavailable androgen, blockade of androgen action at target tissues, stabilization of the endometrium, and reduction of insulin resistance. Although the original description of PCOS by Stein and Leventhal was published in 1935, the cause of PCOS remains unknown. This reason, coupled with the fact that PCOS-related insulin resistance is an important cause of NIDDM in women, has caused this disorder to become one of interest and active investigation. Future research will likely be able to delineate mechanisms behind the defects of carbohydrate metabolism and ascertain large multigeneration kindreds for linkage analyses to identify affected genes. Future studies are also likely to confirm whether young women with PCOS are at increased risk for cardiovascular disease and other long-term health complications. As new pathophysiologic mechanisms are identified, the promise of new therapies arises, including treatments that could potentially reduce the long-term incidence of adverse health consequences.
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PMID:Menstrual disorders in adolescents. Excess androgens and the polycystic ovary syndrome. 1038 5

Polycystic ovary syndrome(PCOS) is characterized by clinical symptoms such as menstrual dysfunction, unovulatory infertility, masculinization, obesity, polycystic ovary by ultrasound, and endocrine abnormalities such as hyperandrogenism, and elevated LH to FSH ratio. Recent reports suggest that insulin resistance plays an important role in the pathogenesis of PCOS, and several insulin sensitizing agents have been used for the treatment of PCOS. Troglitazone, one of the thiazolidinediones, improves not only insulin sensitivity but also hyperandrogenism and ovulatory function. Troglitazone appears to be useful in treating women with PCOS. Further investigations are needed to assess the effectiveness and safety.
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PMID:[Troglitazone for treatment of polycystic ovary syndrome]. 1070 78

Aromatase enzyme is the product of the CYP19 gene. Human aromatase deficiency is a rare disorder and is usually caused by single base-pair changes resulting in amino acid substitution or premature stop codons. In most cases, the affected mother presents with virilization in the third trimester of pregnancy. Affected female newborns have pseudohemaphrodism with clitoromegaly and hypospadias. The cause of these presentations in pregnancy is the inability to convert fetal dehydroepiandrosterone to estrogen in the placenta and subsequent conversion to androgens in the periphery. Affected male newborns present with tall stature secondary to failed epiphyseal fusion. They also have delayed bone age, osteopenia, and undermineralization, which can be corrected with the addition of estrogen, highlighting estrogen's critical role in men as well as women. The aromatase knock-out male mouse (ArKO) has shortened femur length and bone undermineralization. Female ArKO mice at 10-12 weeks have multiple ovarian follicles arrested in the antral phase and stromal hyperplasia. By 1 year the ovaries become grossly dysmorphic with numerous cystic follicles and fibrous stroma. Male ArKO mice testes demonstrate arrest of spermatogenesis at the level of round spermatids and Leydig cell hyperplasia. ArKO mice also exhibit evidence of insulin resistance and visceral adiposity.
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PMID:Genetic mutations resulting in loss of aromatase activity in humans and mice. 1073 24

Male sexual differentiation relies upon testicular secretion of the hormones testosterone, Mullerian inhibiting substance, and insulin-3 (Insl3). Insl3 is responsible for testicular descent through virilization and outgrowth of the embryonic gubernaculum. In mouse, prenatal exposure to 17beta-estradiol and the nonsteroidal synthetic estrogen diethylstilbestrol (DES) disturbs the endocrine balance, causing demasculinizing and feminizing effects in the male embryo, including impaired testicular descent (cryptorchidism). In the current study, we show that maternal exposure to estrogens, including 17alpha- and beta-estradiol, as well as DES, specifically down regulates Insl3 expression in embryonic Leydig cells, thereby providing a mechanism for cryptorchidism. These experiments may have implications for the widespread use of estrogenic substances in agriculture and the environment.
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PMID:A molecular basis for estrogen-induced cryptorchidism. 1092 72

Congenital lipodystrophy is an uncommon autosomal recessive disorder that occurs mainly in females and is characterized by loss of subcutaneous fat, insulin-dependent diabetes mellitus, and masculinization due to defective metabolism of fat. Acquired lipodystrophy is now most commonly encountered in patients infected with HIV who take protease inhibitors. We present an illustrative case of lipodystrophy and review the presenting signs allowing for an accurate clinical diagnosis.
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PMID:Lipodystrophy. 1123 28

HAIR-AN syndrome is an acronym for an unusual multisystem disorder in women that consists of hyperandrogenism (HA), insulin resistance (IR) and acanthosis nigricans (AN). The precipitating abnormality is thought to be insulin resistance, with a secondary increase in insulin levels and subsequent overproduction of androgens in the ovaries. Long periods of hyperinsulinism and, some suspect, hyperandrogenism can result in the cutaneous manifestation of acanthosis nigricans. Patients are often concerned about the physical manifestations of this disorder, including virilization and acanthosis nigricans, and may be less aware of systemic problems. Physicians should assess women with these problems for an underlying endocrine abnormality. Although a treatment regimen for the HAIR-AN syndrome has not been established, antiandrogen therapy and weight loss are useful.
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PMID:HAIR-AN syndrome: a multisystem challenge. 1143 Apr 53


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