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Tina Kellercosta - One of the best experts on this subject based on the ideXlab platform.
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a multi component pheromone in the urine of dominant male tilapia oreochromis mossambicus reduces aggression in rivals
2016Co-Authors: Tina Kellercosta, Joao Saraiva, Peter C Hubbard, Eduardo N Barata, Adelino V M CanarioAbstract:Males often use scent to communicate their dominance, and to mediate aggressive and breeding behaviors. In teleost fish, however, the chemical composition of male pheromones is poorly understood. Male Mozambique tilapia, Oreochromis mossambicus, use urine that signals social status and primes females to spawn. The urinary sex pheromone directed at females consists of 5β-pregnane-3α,17α,20β-triol 3-glucuronate and its 20α-epimer. The concentration of these is positively correlated with male social rank. This study tested whether dominant male urine reduces aggression in receiver males, and whether the Pregnanetriol 3-glucuronates also reduce male-male aggression. Males were allowed to fight their mirror image when exposed to either: i) water control or a chemical stimulus; ii) dominant male urine (DMU); iii) C18-solid phase (C18-SPE) DMU eluate; iv) C18-SPE DMU eluate plus filtrate; v) the two Pregnanetriol 3-glucuronates (P3Gs); or vi) P3Gs plus DMU filtrate. Control males mounted an increasingly aggressive fight against their image over time. However, DMU significantly reduced this aggressive response. The two urinary P3Gs did not replicate the effect of whole DMU. Neither did the C18-SPE DMU eluate, containing the P3Gs, alone, nor the C18-SPE DMU filtrate to which the two P3Gs were added. Only exposure to reconstituted DMU (C18-SPE eluate plus filtrate) restored the aggression-reducing effect of whole DMU. Olfactory activity was present in the eluate and the polar filtrate in electro-olfactogram studies. We conclude that P3Gs alone have no reducing effect on aggression and that the urinary signal driving off male competition is likely to be a multi-component pheromone, with components present in both the polar and non-polar urine fractions.
Adelino V M Canario - One of the best experts on this subject based on the ideXlab platform.
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a multi component pheromone in the urine of dominant male tilapia oreochromis mossambicus reduces aggression in rivals
2016Co-Authors: Tina Kellercosta, Joao Saraiva, Peter C Hubbard, Eduardo N Barata, Adelino V M CanarioAbstract:Males often use scent to communicate their dominance, and to mediate aggressive and breeding behaviors. In teleost fish, however, the chemical composition of male pheromones is poorly understood. Male Mozambique tilapia, Oreochromis mossambicus, use urine that signals social status and primes females to spawn. The urinary sex pheromone directed at females consists of 5β-pregnane-3α,17α,20β-triol 3-glucuronate and its 20α-epimer. The concentration of these is positively correlated with male social rank. This study tested whether dominant male urine reduces aggression in receiver males, and whether the Pregnanetriol 3-glucuronates also reduce male-male aggression. Males were allowed to fight their mirror image when exposed to either: i) water control or a chemical stimulus; ii) dominant male urine (DMU); iii) C18-solid phase (C18-SPE) DMU eluate; iv) C18-SPE DMU eluate plus filtrate; v) the two Pregnanetriol 3-glucuronates (P3Gs); or vi) P3Gs plus DMU filtrate. Control males mounted an increasingly aggressive fight against their image over time. However, DMU significantly reduced this aggressive response. The two urinary P3Gs did not replicate the effect of whole DMU. Neither did the C18-SPE DMU eluate, containing the P3Gs, alone, nor the C18-SPE DMU filtrate to which the two P3Gs were added. Only exposure to reconstituted DMU (C18-SPE eluate plus filtrate) restored the aggression-reducing effect of whole DMU. Olfactory activity was present in the eluate and the polar filtrate in electro-olfactogram studies. We conclude that P3Gs alone have no reducing effect on aggression and that the urinary signal driving off male competition is likely to be a multi-component pheromone, with components present in both the polar and non-polar urine fractions.
Cedric H L Shackleton - One of the best experts on this subject based on the ideXlab platform.
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dehydrosteroid measurements in maternal urine or serum for the prenatal diagnosis of smith lemli opitz syndrome slos
2007Co-Authors: Cedric H L Shackleton, Richard I. Kelley, Lisa E Kratz, Josep Marcos, Wendy Y Craig, Glenn E Palomaki, James E HaddowAbstract:In a large multi-center trial involving prenatal screening for Smith–Lemli–Opitz syndrome (SLOS), we evaluated maternal urine and serum steroid analysis as a non-invasive diagnostic alternative to amniotic fluid sterol analysis. Candidate steroid ratios included: 7-dehydroPregnanetriol/Pregnanetriol (7-PT/PT), 8-dehydroPregnanetriol/PT (8-PT/PT), the sum of these two (7 + 8-PT/PT), and dehydroestriol/estriol (DHE3/E3). Results are presented from 19 SLOS pregnancies, and 732 reference pregnancies that were screen positive for SLOS but negative on testing in amniotic fluid. Steroid ratios are expressed as multiples of the 75th centile (MoS), rather than multiples of the median, as most reference measurements were undetectable. All four urine ratios were available in 12 SLOS pregnancies; the median 7-PT/PT MoS was 94, with no overlap between affected and reference pregnancies in the second trimester. The separation between these groups increased by 27% per week. The other three ratios performed similarly in urine, with (7 + 8)-PT/PT ratios being marginally superior, due to fewer high reference outliers. All four steroid ratios in urine were diagnostic for SLOS between 14 and 22 weeks' gestation. In six SLOS pregnancies in which all serum analytes were measured, the median 7-PT/PT MoS was 71, and there was slight overlap in the second trimester. The separation increased by 28% per week. Steroid ratios in serum were less definitive than in urine but might be useful in certain circumstances, at 14 weeks gestation or later. Urine testing performance prior to 14 weeks gestation appears promising, but reference data are sparse. © 2007 Wiley-Liss, Inc.
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identification of 7 8 and 8 9 unsaturated adrenal steroid metabolites produced by patients with 7 dehydrosterol δ7 reductase deficiency smith lemli opitz syndrome
2002Co-Authors: Cedric H L Shackleton, Esther Roitman, William K Wilson, Forbes D PorterAbstract:Patients with Smith–Lemli–Opitz syndrome have impaired ability to synthesize cholesterol due to attenuated activity of 7-dehydrosterol-Δ7-reductase which catalyses the final step in cholesterol synthesis. Accumulation of 7- and 8-dehydrocholesterol is a result of the disorder and potentially these sterols could be used as precursors of a novel class of Δ7 and Δ8 unsaturated adrenal steroids and their metabolites. In this study, we have analyzed urine from SLOS patients in the anticipation of characterizing such metabolites. Gas chromatography/mass spectrometry (GC/MS) was used in the identification of two major metabolites as 7- and 8-dehydroversions of the well-known steroid Pregnanetriol. Other steroids, such as 8-dehydro dehydroepiandrosterone (8-dehydro DHEA) and 7- or 8-dehydroandrostenediol were also identified, and several more steroids are present in urine but remain uncharacterized. As yet, the study provides no evidence for the production of ring-B unsaturated metabolites of complex steroids, such as cortisol. We believe that the following transformations can utilize ring-B dehydroprecursors: StAR transport of cholesterol, p450 side chain cleavage, 17-hydroxylase/17,20-lyase, 3β-hydroxysteroid dehydrogenase, 3α-hydroxysteroid dehydrogenase, 17β-hydroxysteroid dehydrogenase, 20α-hydroxysteroid dehydrogenase and 5β-reductase. We have yet to prove the activity of adrenal 21-hydroxylase, 11β-hydroxylase or 5α-reductase towards 7- or 8-dehydroprecursors.
W M Teller - One of the best experts on this subject based on the ideXlab platform.
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urinary excretion of 17 hydroxypregnanolones in patients with different forms of congenital adrenal hyperplasia due to steroid 21 hydroxylase deficiency
1992Co-Authors: J Homoki, J Solyom, Ulrich Wachter, W M TellerAbstract:To improve diagnostic criteria in different (classical salt-wasting (SW), classical simple virilizing (SV) and non classical late onset (LO)) forms of congential adrenal hyperplasia (CAH) due to steroid 21-hydroxylase deficiency, we investigated the urinary excretion of 17-hydroxypregnanolones (17OH-PO(5β) and (5α), 15β-hydroxypregnanolone(15βOH-PO), Pregnanetriol(PT) and 11-oxo-Pregnanetriol (11-O-PT) compared to hydrocortisone metabolities During the 1st month of life newborn infants with CAH-SW excreted from barely detectable to very large amounts of 17OH-PO(5β), 15βOH-PO and PT, and, in 12 of 14 cases, also 11-O-PT in their urines. From the 1st to the 28th day of life, cortisol metabolites were virtually absent in urines of CAH-SW infants. This was in contrast of 36 healthy newborn infants. We measured the excretion of 17OH-PO(5α) in children with CAH of whom 19 patients with CAH-SV had a median 17OH-PO(5α) excretion of 1110 μg/day (range: 152–5515). In 21patients with CAH-LO, median excretion of 17OH-PO(5α) was 294μg/day (range: 66–1273). Besides the conventional metabolites of 17-hydroxyprogesterone (17OH-PO(5β), PT and 11-O-PT),no 17OH-PO(5α) was detected in the urines of 14 patients with precocious pubarche, in 14 patients with virilization of unknown origin and in 94 healthy children of comparable age. The ratio of 17OH-PO(5α) to tetrahydrocortisone (THE) discriminated between CAH-SV and CAH-LO from the 1st to the 18th year of age. The determination of urinary 17OH-PO(5α) is an excellent diagnostic method in CAH-SV as well as CAH-LO.
Forbes D Porter - One of the best experts on this subject based on the ideXlab platform.
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identification of 7 8 and 8 9 unsaturated adrenal steroid metabolites produced by patients with 7 dehydrosterol δ7 reductase deficiency smith lemli opitz syndrome
2002Co-Authors: Cedric H L Shackleton, Esther Roitman, William K Wilson, Forbes D PorterAbstract:Patients with Smith–Lemli–Opitz syndrome have impaired ability to synthesize cholesterol due to attenuated activity of 7-dehydrosterol-Δ7-reductase which catalyses the final step in cholesterol synthesis. Accumulation of 7- and 8-dehydrocholesterol is a result of the disorder and potentially these sterols could be used as precursors of a novel class of Δ7 and Δ8 unsaturated adrenal steroids and their metabolites. In this study, we have analyzed urine from SLOS patients in the anticipation of characterizing such metabolites. Gas chromatography/mass spectrometry (GC/MS) was used in the identification of two major metabolites as 7- and 8-dehydroversions of the well-known steroid Pregnanetriol. Other steroids, such as 8-dehydro dehydroepiandrosterone (8-dehydro DHEA) and 7- or 8-dehydroandrostenediol were also identified, and several more steroids are present in urine but remain uncharacterized. As yet, the study provides no evidence for the production of ring-B unsaturated metabolites of complex steroids, such as cortisol. We believe that the following transformations can utilize ring-B dehydroprecursors: StAR transport of cholesterol, p450 side chain cleavage, 17-hydroxylase/17,20-lyase, 3β-hydroxysteroid dehydrogenase, 3α-hydroxysteroid dehydrogenase, 17β-hydroxysteroid dehydrogenase, 20α-hydroxysteroid dehydrogenase and 5β-reductase. We have yet to prove the activity of adrenal 21-hydroxylase, 11β-hydroxylase or 5α-reductase towards 7- or 8-dehydroprecursors.