Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002453 (amenorrhea)
 6,245 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The concentrations of plasma melatonin and cortisol were determined every 20 min during a 24 h period in 6 women aged 24 to 45 years with Cushing's syndrome of differing aetiologies (4 adrenal adenomas, 2 adrenal hyperplasia). Melatonin was assayed after chloroform extraction according to the method of Rollag and Niswender (1976). Abnormal melatonin secretory patterns were found in all the patients; 24 h melatonin concentration means varied from 130 to 413 pg/ml and were not significantly higher than the 24 h mean in 4 controls (215 +/- 126 pg/ml). All six subjects however showed a significant increase of melatonin during the day period (302 +/- 109 as compared with controls 129 +/- 65 mg/ml, mean +/- SD; P less than 0.005). No relationship could be found between abnormal melatonin levels and the sexual status of the patients (4 with amenorrhoea, 2 normally menstruating women). An alteration of melatonin secretory pattern is present in Cushing's syndrome, whatever the aetiology. It is suggested that hypercortisolism, by itself, may modify the pattern of melatonin secretion.
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PMID:24 hour melatonin secretory pattern in Cushing's syndrome. 668 4

Premature ovarian insufficiency (POI) is defined as the cessation of ovarian function under the age of 40 years and is characterized by amenorrhea, hypoestrogenism, and elevated serum gonadotrophin concentration (FSH). It is a heterogeneous disorder with a multicausal pathogenesis; however, majority of cases are idiopathic. In idiopathic POI, involvement of unknown mechanisms may increase rate of oocyte apoptosis. Studies have shown that elevated reactive oxygen species (ROS) levels affect the quality of gametes. Mitochondrial mutations in different complexes of electron transport chain have been reported to disrupt the electron flow which lead to formation of more superoxide ions or increased levels of ROS. This study was aimed to screen the mitochondrial genome for variations in idiopathic POI (n = 25) and occult ovarian insufficiency (OI) (n = 5) patients. 30 patients diagnosed with POI and occult OI were enrolled in this study. Blood samples were collected from the patients and controls. DNA was extracted using phenol chloroform method. A total of 102 nucleotide variations were observed in patients as compared with 58 nucleotide variations in controls. 24% variations were found to be non-synonymous and 76% were synonymous. It was found that 48% variations were in complex I, 8% in complex III, 24% in complex IV, and 20% in complex V of electron transport chain. We found most of the non-synonymous mitochondrial variations in complex I (48%) of the respiratory chain which is the largest enzyme complex and is associated with oxidative stress. Some non-synonymous pathogenic alterations (p.M31T, p.W239C, p.L128Q) and non pathogenic alterations (ATPase6:p.T53I, ATPase6:p.L190F, ATPase6:p.L199L) were found to be significantly higher in cases as compared with controls. The preliminary data suggest that the mitochondrial mutations and subsequent decline in ATP levels may accelerate follicular atresia and lead to POI. The results of this preliminary study highlight the need to extend this study by analyzing large number of samples in different ethnic populations and analyze for ROS levels and mitochondrial mutations in oocytes as they are of different embryonic origin and develop in a different microenvironment.
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PMID:Nucleotide variations in mitochondrial DNA and supra-physiological ROS levels in cytogenetically normal cases of premature ovarian insufficiency. 2068 Mar 10