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1.
Mol Biochem Parasitol ; 249: 111474, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35307401

RESUMO

The rapid spread of drug resistant malaria parasites has necessitated the search for novel antimalarials and chemosensitizers capable of reversing drug resistance in the parasites. A number of studies have revealed the resistance reversal activities of pregnane glycosides and the antimalarial activity of a pregnane glycoside obtained from Gongronema species. However, the pregnane (2) and pregnane glycosides (1, 3-4) isolated from Gongronema latifolium leaf have not been evaluated for these activities. This study was therefore carried out to evaluate the antiplasmodial and chloroquine resistance reversal activities of a pregnane and three pregnane glycosides isolated from G. latifolium leaf in vitro. The compounds were evaluated for their inhibitory activities against P. falciparum 3D7 (a chloroquine-sensitive strain) and P. falciparum W2 (a chloroquine-resistant clone) in vitro. The activities of chloroquine in separate combination with each of the compounds against P. falciparum W2 were also evaluated. Moreover, the interaction of the active compounds (1 and 4) with selected P. falciparum proteins (PfProteins) were evaluated in silico. The results revealed that only 1 and 4 were active against P. falciparum 3D7 and P. falciparum W2. Also, 2 and 3 did not exhibit chloroquine resistance reversal activity. Activity of chloroquine against P. falciparum W2 was potentiated by 1 by 3200% at concentrations higher than 0.625 µg/mL. Also, 1 and 4 demonstrated similar binding patterns and higher binding tendencies to the selected PfProteins compared to chloroquine. Thus, 1 (iloneoside) is an antimalarial pregnane glycoside which can potentiate the activity of chloroquine against multidrug resistant P. falciparum.


Assuntos
Antimaláricos , Apocynaceae , Antagonistas do Ácido Fólico , Malária Falciparum , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Cloroquina/farmacologia , Resistência a Medicamentos , Antagonistas do Ácido Fólico/farmacologia , Glicosídeos/análise , Glicosídeos/farmacologia , Malária Falciparum/tratamento farmacológico , Folhas de Planta/química , Plasmodium falciparum , Pregnanos/análise , Pregnanos/farmacologia
2.
J Chromatogr Sci ; 58(5): 454-463, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32166322

RESUMO

The dried root of Asparagus cochinchinensis (RAC) has been used as an important traditional Chinese medicine for a long time in China. Steroidal saponins (SSs) are considered to be the main active ingredients of this herb. However, the isolation and structural determination of SSs from RAC are time-consuming and laborious. For this reason, the development of new methods for the separation and characterization of SSs is highly desirable. In this study, a new high-performance liquid chromatography coupled to electrospray ionization and quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS/MS) method with precursor ions and the corresponding fragment ions was developed for the identification of SSs in RAC. Finally, 30 SSs have been detected and identified, including 17 potential new compounds. This is the first systematic study of SSs in RAC by HPLC-ESI-QTOF-MS/MS method.


Assuntos
Asparagus/química , Cromatografia Líquida de Alta Pressão/métodos , Saponinas/análise , Medicamentos de Ervas Chinesas/química , Glicosídeos/análise , Glicosídeos/química , Raízes de Plantas/química , Pregnanos/análise , Pregnanos/química , Saponinas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espirostanos/análise , Espirostanos/química , Esteroides/análise , Esteroides/química , Esteróis/análise , Esteróis/química , Espectrometria de Massas em Tandem/métodos
3.
Am J Primatol ; 80(11): e22917, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30221787

RESUMO

The wild population of spectral tarsier is declining and attempts to breed the species in captivity have been of limited success. One possible reason for this is that information on the reproductive biology of Tarsius tarsier is extremely limited and data on the species reproductive physiology are completely lacking. We validated fecal estrogen (E-total) and progesterone metabolite (5-P-3OH) measurements for monitoring female ovarian activity and pregnancy. We used this approach to provide the first data on cycle and pregnancy length based on endocrine information in this species. We collected regular fecal samples in combination with observations on socio-sexual behaviors for a maximum of 15 months from three females maintained at Primate Research Center of Bogor Agricultural University, Indonesia. Hormonal profiles indicated that behavioral estrus was associated with marked elevations in fecal E-total concentrations followed by increases in 5-P-3OH levels indicating luteal function. Pregnancy was characterized by low levels of E-total and 5-P-3OH during the first month and markedly rising concentrations thereafter. An ovarian cycle length of 21.7 ± 5.7 days was found. Gestation length was 128d (live infant), 131d (stillbirth), and 164d (death of mother and infant due to dystocia). Despite the small sample size, the study demonstrates the overall validity of fecal sex hormone metabolite measurements for reproductive monitoring in female T. tarsier, as such, the methods described here may ultimately help to improve the breeding management of the species in captivity. They may also offer new opportunities for investigating basic questions of tarsier reproductive biology in the wild by using fecal hormone metabolite analysis to diagnose pregnant animals and determine reproductive rates in relation to ecological and other factors influencing tarsier reproduction. Thus, non-invasive assessment of female reproductive condition as described here may ultimately contribute to facilitate in and ex situ conservation efforts of this endangered primate species.


Assuntos
Ciclo Menstrual/fisiologia , Gravidez/fisiologia , Comportamento Sexual Animal/fisiologia , Tarsiidae/fisiologia , Animais , Distocia/mortalidade , Distocia/veterinária , Estrogênios/análise , Fezes/química , Feminino , Pregnanos/análise , Natimorto/veterinária , Tarsiidae/metabolismo
4.
Nat Prod Res ; 30(9): 1060-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26595507

RESUMO

Phytochemical investigation of Gomphocarpus fruticosus (L.) Ait. of Egyptian origin afforded the new pregnane glycoside lineolon-3-O-[ß-D-oleandropyranosyl-(1-4)-ß-D-cymaropyranosyl-(1-4)-ß-D-cymaropyranoside], along with six known compounds. The structures of the isolated compounds were elucidated on the basis of extensive spectroscopic evidences derived from 1D, 2D NMR experiments, mass spectrometry and by comparing their physical and spectroscopic data to literature. These included the triterpenoids 3ß-taraxerol, 3ß-taraxerol acetate and betulinic acid, which are identified for the first time in G. fruticosus and the cardenolides uzarigenin, gomphoside and calotropin.


Assuntos
Apocynaceae/química , Glicosídeos/análise , Pregnanos/análise , Egito , Glicosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Extratos Vegetais/análise , Pregnanos/isolamento & purificação
5.
Theriogenology ; 85(2): 216-23, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26454526

RESUMO

The Himalayan musk deer (Moschus chrysogaster), an endangered species, is facing threat of extinction globally due to severe hunting for its musk, and efforts are under way in India to breed them in captivity. However, no information is available on the reproductive cycles of the species. In this study, we aimed to standardize an enzyme immunoassay (EIA) procedure for monitoring pregnancy using fecal samples. We collected fecal samples for 12 months from five captive females maintained at the Musk Deer Research Centre, Bageshwar, Uttarakhand, India. Three of these females were observed mating and gave birth, whereas two were seen mating but did not give birth. The gestation periods for the three females were 183, 185, and 199 days, respectively. High-pressure liquid chromatography revealed the presence of immunoreactive pregnanediol-3-glucuronide (PdG), progesterone, and 5α-pregnan-3α-ol-20-one (5-alpha-pregnane) metabolites in the fecal samples. We used EIAs against progesterone, PdG, and 5-alpha-pregnane to monitor pregnancy. We found PdG EIA to be a highly accurate and sensitive assay compared with the other two assays in detecting pregnancy. We conclude that PdG EIA can be used to diagnose and monitor pregnancy in Himalayan musk deer using fecal steroid analysis, at an early stage of 3 months after mating. This study would help in conservation breeding of musk deer in captivity and in monitoring the reproductive status of the species in the wild.


Assuntos
Fezes/química , Testes de Gravidez/veterinária , Progestinas/análise , Ruminantes , Animais , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Feminino , Técnicas Imunoenzimáticas/veterinária , Índia , Gravidez , Testes de Gravidez/métodos , Pregnanodiol/análogos & derivados , Pregnanodiol/análise , Pregnanos/análise , Progesterona/análise , Sensibilidade e Especificidade
6.
Anim Reprod Sci ; 161: 89-95, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26372226

RESUMO

Unlike their wild counterparts, many white rhinoceros females in captivity fail to reproduce successfully such that current captive populations are not self-sustaining. The causes of the problem are poorly understood. Variation in cycle length and long periods of acyclicity are characteristics of the majority of these non-reproducing females in captivity but it is unknown whether these characteristics are a feature of reproductively successful free-ranging females. This study therefore aimed to monitor cyclic activity in a wild population of southern white rhinoceros at Lapalala Wilderness, South Africa, by measuring the concentrations of immunoreactive fecal progestagen metabolites (fPM). Five adult females were tracked twice per week for 20 months and if located a fresh fecal sample was collected. Reproductive events and group structural dynamics were also recorded and subsequently correlated with the fPM data. The baseline concentration of fPM was 0.69±0.20µg/g DW while concentrations during pregnancy were 30-400-fold higher. The females exhibited estrous cycle lengths of 30.6±7.7 days and, based on fPM data, gestation length in one female was 502±3 days. Year-round monitoring showed no clear evidence of seasonality in ovarian activity. During cyclic luteal activity females were often seen in the presence of a dominant bull. One female stopped cycling after removal of the local dominant bull and luteal activity only returned after a new bull was introduced. This suggests that white rhinoceros females in the wild might need external stimuli from a male to ovulate. These findings indicate that the irregular cyclicity reported for white rhinoceros housed in zoos and animal parks may result from conditions in captivity and account for reduced fertility.


Assuntos
Ciclo Estral/fisiologia , Perissodáctilos/fisiologia , Pregnanos/análise , Animais , Animais Selvagens/fisiologia , Fezes/química , Feminino
7.
Food Chem Toxicol ; 59: 111-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23770343

RESUMO

The current study aimed at evaluating the potential and mechanisms of the antidiabetic activity of the methanolic extract (ME) of Caralluma tuberculata as well as its chloroform (CF), n-butanol (BF) and the remaining water fractions (RFs) in streptozotocin-induced diabetic rats. The antidiabetic activity was evaluated through assessing fasting blood glucose (FBG), insulin levels, oral glucose tolerance test (OGTT), glucose utilization by isolated rat psoas muscle, gut glucose absorption and G-6-Pase activity in isolated rat liver microsomes. Both ME and RF showed the highest potency, where ME had superior activity. The mechanism underlying the observed antihyperglycemic activity of ME could be attributed, at least in part, to enhanced skeletal muscle utilization of glucose, inhibition of hepatic gluconeogenesis and stimulation of insulin secretion. ME was standardized through LC-MS analysis for its major pregnanes.


Assuntos
Apocynaceae/química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Modelos Animais de Doenças , Hipoglicemiantes/uso terapêutico , Fitoterapia , Componentes Aéreos da Planta/química , Extratos Vegetais/uso terapêutico , Animais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Etnofarmacologia , Gluconeogênese/efeitos dos fármacos , Glucose/metabolismo , Hipoglicemiantes/análise , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Insulina/sangue , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Absorção Intestinal/efeitos dos fármacos , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Pregnanos/análise , Pregnanos/isolamento & purificação , Pregnanos/uso terapêutico , Músculos Psoas/efeitos dos fármacos , Músculos Psoas/metabolismo , Ratos , Ratos Sprague-Dawley , Arábia Saudita , Solventes/química
8.
Theriogenology ; 78(1): 77-85, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22444560

RESUMO

Because of overpopulation of African elephants in South Africa and the consequent threat to biodiversity, the need for a method of population control has become evident. In this regard, the potential use of the porcine zona pellucida (pZP) vaccine as an effective means for population control is explored. While potential effects of pZP treatment on social behavior of African elephants have been investigated, no examination of the influence of pZP vaccination on the endocrine correlates in treated females has been undertaken. In this study, ovarian activity of free-ranging, pZP-treated African elephant females was monitored noninvasively for 1 yr at Thornybush Private Nature Reserve, South Africa, by measuring fecal 5α-pregnan-3ß-ol-20-on concentrations via enzyme immunoassay. A total of 719 fecal samples from 19 individuals were collected over the study period, averaging 38 samples collected per individual (minimum, maximum: 16, 52). Simultaneously, behavioral observations were made to record the occurrence of estrous behavior for comparison. Each elephant under study showed 5α-pregnan-3ß-ol-20-on concentrations rising above baseline at some period during the study indicating luteal activity. Average 5α-pregnan-3ß-ol-20-on concentrations were 1.61 ± 0.46 µg/g (mean ± SD). Within sampled females, 42.9% exhibited estrous cycles within the range reported for captive African elephants, 14.3% had irregular cycles, and 42.9% did not appear to be cycling. Average estrous cycle duration was 14.72 ± 0.85 wk. Estrous behavior coincided with the onset of the luteal phase and a subsequent rise in 5α-pregnan-3ß-ol-20-on concentrations. Average 5α-pregnan-3ß-ol-20-on levels positively correlated with rainfall. No association between average individual 5α-pregnan-3ß-ol-20-on concentrations or cyclicity status with age or parity were detected. Earlier determination of efficacy was established via fecal hormone analysis with no pregnancies determined 22 mo post-treatment and onward. Results indicate the presence of ovarian activity amongst pZP-treated female African elephants in 2 yr after initial immunization. Further study should now be aimed toward investigating the long-term effects of pZP vaccination on the reproductive function of female African elephants.


Assuntos
Elefantes , Fezes/química , Pregnanos/análise , Vacinas Anticoncepcionais/uso terapêutico , Zona Pelúcida/imunologia , Animais , Animais Selvagens , Comportamento Animal/fisiologia , Elefantes/imunologia , Elefantes/metabolismo , Elefantes/fisiologia , Ciclo Estral/metabolismo , Ciclo Estral/fisiologia , Feminino , Fase Luteal/metabolismo , Masculino , Concentração Osmolar , Controle da População/métodos , Pregnanos/metabolismo , África do Sul , Suínos
9.
J AOAC Int ; 94(5): 1383-90, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22165002

RESUMO

An HPLC method was developed for the quantitative determination of five pregnane derivatives from aerial parts of Caralluma species and dietary supplements. The method was validated for linearity, repeatability, LOD, and LOQ. The LOD and LOQ of five pregnane compounds were found to be in the range of 1-5 and 3-15 microg/mL, respectively, by HPLC using photodiode array detection. This method was applied to the identification of three plant materials of Caralluma species (C. fimbriata, C. umbellate, and C. attentuata) and seven dietary supplements claiming to contain C. fimbriata. An LCIMS coupled with electrospray ionization interface method was used for the identification of compounds and involved the use of [M+Na]+ ions in the positive ion mode with extracted ion chromatogram.


Assuntos
Apocynaceae/química , Pregnanos/análise , Calibragem , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Suplementos Nutricionais/análise , Micro-Ondas , Opuntia/química , Extratos Vegetais/análise , Análise de Regressão , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Ultrassom
10.
Chem Pharm Bull (Tokyo) ; 59(10): 1303-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21963644

RESUMO

Three new steroids dyscusins A-C (1-3), including a stigmastane-type sterol and two pregnanes, together with two known steroids were isolated from the leaves of Dysoxylum cumingianum (Meliaceae). Their structures were elucidated on the basis of extensive spectroscopic analyses. In a cytotoxicity assay, compound 1 showed ten-fold enhanced cytotoxicity against multi-drug resistant cancer cells (KB-C2) in the presence of 2.5 µM colchicine as compared with the absence of colchicine. This notable finding indicated that 1 possessed a multi-drug resistant reversal effect.


Assuntos
Antineoplásicos Fitogênicos/química , Meliaceae/química , Fitoterapia , Pregnanos/química , Esteroides/química , Esteróis/química , Antineoplásicos Fitogênicos/análise , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Colchicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Folhas de Planta/química , Pregnanos/análise , Pregnanos/isolamento & purificação , Pregnanos/farmacologia , Esteroides/análise , Esteroides/isolamento & purificação , Esteroides/farmacologia , Esteróis/análise , Esteróis/isolamento & purificação , Esteróis/farmacologia , Moduladores de Tubulina/farmacologia
11.
Nat Prod Res ; 25(17): 1621-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22011221

RESUMO

From the fruits and leaves of Aglaia erythrosperma (Meliaceae), 10 chemical constituents were isolated and identified, i.e. the dammarane triterpenoids cabraleadiol (1), cabraleahydroxylactone (2), ethyl eichlerianoate (3), eichlerialactone (4), aglinin A (5), cabralealactone (6), the aglaialactone 5,6-desmethylenedioxy-5-methoxy-aglalactone (7), the flavagline 4'-demethoxy-3',4'-methylenedioxy-methyl rocaglate (8) and two coumarins: scoparone and scopoletin. Flavagline 8 exhibited antimalarial activity with an IC(50) value of 7.30 µg mL(-1) and was strongly cytotoxic against small cell lung cancer (NCI-H187), epidermoid carcinoma (KB) and breast cancer (BC) cell lines, with IC(50) values of 2.17, 2.10 and 0.11 µg mL(-1), respectively. Aglinin A (5) displayed moderate cytotoxicity against all the three cancer cell lines, whereas ethyl eichlerianoate (3), cabralealactone (6) and the aglaialactone 7 were exclusively cytotoxic to NCI-H187 cell line. Cabraleahydroxylactone (2) showed antiviral activity against herpes simplex virus type-1 with an IC(50) value of 3.20 µg mL(-1), in comparison with the standard acyclovir (IC(50) = 1.90 µg mL(-1)). When tested for antimycobacterial activity against Mycobacterium tuberculosis H(37)Ra, compounds 1-4 and 6-8 displayed minimum inhibitory concentration in the range of 25-50 µg mL(-1).


Assuntos
Aglaia/química , Antibacterianos/isolamento & purificação , Antimaláricos/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Antivirais/isolamento & purificação , Benzofuranos/isolamento & purificação , Frutas/química , Folhas de Planta/química , Antibacterianos/análise , Antibacterianos/farmacologia , Antimaláricos/análise , Antimaláricos/farmacologia , Antineoplásicos Fitogênicos/análise , Antineoplásicos Fitogênicos/farmacologia , Antivirais/análise , Antivirais/farmacologia , Benzofuranos/análise , Benzofuranos/farmacologia , Linhagem Celular Tumoral , Cumarínicos/análise , Cumarínicos/isolamento & purificação , Citotoxinas/análise , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Fitosteróis/análise , Fitosteróis/isolamento & purificação , Pregnanos/análise , Pregnanos/isolamento & purificação , Espectrofotometria Ultravioleta , Tailândia
12.
Gen Comp Endocrinol ; 164(2-3): 125-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19501091

RESUMO

Avian eggs contain a variety of steroid hormones, which have been attributed as a tool for maternal phenotypic engineering. The majority of studies focuses on androgens, but also significant amounts of progesterone as well as other steroid hormones have been measured. The question if corticosterone is also present in eggs of chickens is currently under debate. The only analytical validation performed so far has failed to demonstrate corticosterone in the yolk of chickens, suggesting that antibodies for corticosterone measurement cross-react with other steroids present in the yolk. In order to investigate this assumption and to characterise potential cross-reacting hormones in more detail, we performed high-performance liquid chromatographic (HPLC) analyses of chicken yolk extracts and determined the concentration of immunoreactive corticosterone, progesterone and cortisol. The progesterone antibody revealed several immunoreactive substances, including progesterone, pregnenolone and two substances with lower polarity. The corticosterone enzyme immunoassay detected immunoreactive substances at exactly the same elution positions as the progesterone assay and a very small peak at the elution position of corticosterone. Immunoreactive cortisol was not found. In addition, inner and outer regions of the yolk sphere were analysed separately via HPLC. We found different concentrations of immunoreactive substances between the inner and outer yolk regions, probably reflecting the steroidogenic activity of the follicle cells during oocyte growth. We conclude that in homogenised yolk extracts without previous clean-up, the measured corticosterone concentrations may actually reflect those of progesterone and its precursors, most probably being 5 alpha- and 5 beta-pregnanes and pregnenolone.


Assuntos
Galinhas , Ovos/análise , Glucocorticoides/análise , Progestinas/análise , Animais , Cromatografia Líquida de Alta Pressão , Corticosterona/análise , Gema de Ovo/química , Feminino , Glucocorticoides/imunologia , Pregnanos/análise , Pregnenolona/análise , Progesterona/análise , Progestinas/imunologia
13.
Gen Comp Endocrinol ; 154(1-3): 98-104, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17632105

RESUMO

Compared to teleosts, little is known about the stress response in chondrosteans, and the glucocorticoid(s) most responsive to stress have never been definitively determined in sturgeon. In terms of cortisol production, pallid sturgeon (Scaphirhynchus albus) have a low physiological response to stress compared to other sturgeons (Acipenser s.p.). Because of this, our null hypothesis was that cortisol is not the predominant glucocorticoid secreted in response to stress in pallid sturgeon. Our objective was to identify the putative glucocorticoids present in the plasma of pallid sturgeon during the stress response. Pallid sturgeon were subjected to a severe confinement stress (12 h) with an additional handling stressor for the first 6 h. Control fish were not subjected to confinement but were handled only to collect blood. Blood plasma was collected at time 0, 6, and 12 h. Gas chromatography/mass spectrometry was used to screen the plasma for the spectrum of glucocorticoids and determine the putative steroid secreted during the stress response. Cortisol was the primary glucocorticoid detected in stressed pallid sturgeon. In addition, the cortisol metabolites cortisone, alloTHE (5alpha-pregnane-3alpha,17alpha,21-triol-11,20-dione), allo-alpha-cortolone (3alpha,17alpha,20alpha,21-tetrahydro-5alpha-pregnan-11-one), and allo-beta-cortolone (3alpha,17alpha,20beta,21-tetrahydro-5alpha-pregnan-11-one) were detected. Plasma cortisol increased from a resting concentration of 0.67 ng/ml to 10.66 ng/ml at 6h followed by a decrease to 6.78 ng/ml by 12 h. Plasma glucose increased significantly by time 6 and 12 h in both stressed and unstressed groups and remained elevated at time 12h, while resting lactate concentrations were low to non-detectable and did not increase significantly with the stressor over time. Cortisol was the primary glucocorticoid synthesized and secreted in response to a stressor in pallid sturgeon. Though the proportional increase in plasma cortisol in stressed pallid sturgeon was lower than many other species of sturgeon, the concentration was high enough to elicit a secondary stress response as seen by changes in plasma glucose.


Assuntos
Peixes/sangue , Glucocorticoides/análise , Glucocorticoides/sangue , Estresse Fisiológico/sangue , Animais , Glicemia/análise , Corticosterona/análogos & derivados , Corticosterona/análise , Corticosterona/sangue , Cromatografia Gasosa-Espectrometria de Massas , Hidrocortisona/análise , Hidrocortisona/sangue , Ácido Láctico/sangue , Pregnanos/análise , Pregnanos/sangue
14.
Theriogenology ; 67(9): 1473-84, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17451805

RESUMO

The objective of this study was to develop AI and to achieve first time pregnancy in a nulliparous rhinoceros. For this, one 24-year-old irregular cycling female white rhinoceros was selected, which had never been mated. The endocrine function was monitored by faecal and serum pregnane analysis. Ultrasound determined the optimal day for AI by measuring follicle sizes of 2.0, 2.6, 3.0, 3.2 cm on days -6, -4, -1, 0 of the induced oestrous cycle, respectively. AI was performed and ovulation induced when a pre-ovulatory-sized follicle was present using GnRH analogue, deslorelin. Fresh semen was deposited in the uterine horn using a patented AI catheter overcoming the hymeneal membrane and torturous cervical folds non-surgically. Moreover, ultrasound monitoring of the uterine involution and ovarian activity on days 16, 26, 30 postpartum facilitated the induction of and the AI on the first postpartum oestrous in a rhinoceros using GnRH analogue. Two consecutive pregnancies were achieved by AI for the first time in the rhinoceros. Pregnancies were diagnosed by elevated serum and faecal 20-oxo-pregnane concentrations. In addition ultrasound measured biometric parameters of the two foetuses on days 86 and 133 of gestation. Two female calves were born after 490 and 502 days of gestation, yet one calf was stillborn. AI in rhinoceros might now be used as assisted reproduction technology tool to boost critically small captive rhinoceros populations.


Assuntos
Hormônio Liberador de Gonadotropina/administração & dosagem , Inseminação Artificial/veterinária , Ovulação/efeitos dos fármacos , Perissodáctilos/fisiologia , Anestro , Animais , Fezes/química , Feminino , Feto/fisiologia , Inseminação Artificial/métodos , Masculino , Folículo Ovariano/diagnóstico por imagem , Período Pós-Parto , Gravidez , Resultado da Gravidez , Pregnanos/análise , Sêmen/fisiologia , Fatores de Tempo , Ultrassonografia Pré-Natal/veterinária
15.
Anal Chim Acta ; 586(1-2): 217-22, 2007 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-17386714

RESUMO

A confirmatory method has been developed and validated for the determination of chlormadinone acetate (CMA), megestrol acetate (MGA), melengestrol acetate (MLA) and medroxyprogesterone acetate (MPA) in bovine and porcine plasma. Analytes are extracted from plasma samples using matrix-assisted liquid-liquid extraction (LLE) on Extrelut NT columns followed by C18 solid-phase extraction (SPE). Analytes were analysed using liquid chromatography-tandem mass spectrometry (LC-MS/MS), and quantification was performed using matrix-matched calibration standards in combination with deuterated internal standards. In accordance with Commission Decision 2002/657/EC, two ion transitions were monitored for each analyte. Decision limits (CCalpha) were estimated by analysing 20 blank plasma samples and ranged from 0.1 to 0.2 ng mL(-1). Detection capabilities (CCbeta) were estimated using 20 plasma samples fortified at 0.5 ng mL(-1) and were <0.5 ng mL(-1). In the range 0.5-2 ng mL(-1), the mean intra-laboratory reproducibility of the analytes ranged from 6 to 18% (%R.S.D.). Analytes were shown to be stable in fortified plasma samples for >8 months when stored at -20 degrees C.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Pregnanos/análise , Pregnanos/sangue , Animais , Bovinos , Acetato de Clormadinona/sangue , Cromatografia Líquida de Alta Pressão , Resíduos de Drogas/análise , Acetato de Medroxiprogesterona/sangue , Acetato de Megestrol/sangue , Acetato de Melengestrol/sangue , Modelos Químicos , Suínos
16.
Artigo em Inglês | MEDLINE | ID: mdl-17085081

RESUMO

A sensitive liquid chromatography-electrospray ionization-tandem mass spectrometric (LC-ESI-MS-MS) method for the simultaneous determination of 5alpha-reduced pregnan-type neurosteroids, allopregnanolone (AP), epiallopregnanolone and 5alpha-dihydroprogesterone, in rat brain and serum has been developed and validated. The brain and serum steroids were extracted with methanol-acetic acid, purified using a Strata-X cartridge, derivatized with the permanently charged reagent, 2-hydrazino-1-methylpyridine (HMP), and subjected to LC-positive ESI-MS-MS. The limits of quantitation (LOQ) for brain (0.25 ng/g tissue) and serum (0.25 ng/ml) assays using the derivatization-ESI-MS-MS method are 60-150-fold lower than the LOQs for their atmospheric pressure chemical ionization-MS method without derivatization. [17Alpha,21,21,21-2H4]-AP was used as an internal standard. This method allowed the reproducible and accurate quantification of the brain or serum neurosteroids using a 20 mg or 20 microl sample, respectively. That is, the intra- and inter-assay coefficients of variation were below 8.2 and 6.0%, respectively, and the % accuracy values were 98.5-103.0% for all the steroids in both the brain and serum. The application of the developed method to the analysis of changes in the brain and serum neurosteroid levels by immobilization stress and ethanol administration is also presented.


Assuntos
Encéfalo/metabolismo , Cromatografia Líquida/métodos , Pregnanos/análise , Espectrometria de Massas em Tandem/métodos , Animais , Masculino , Estrutura Molecular , Pregnanos/sangue , Pregnanos/química , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/métodos
17.
J AOAC Int ; 90(6): 1526-31, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18193728

RESUMO

Hoodia gordonii, family Asclepiadaceae, is a succulent plant and is traditionally used in southern Africa for its appetite-suppressant properties. A high-performance liquid chromatographic (HPLC) method with UV detection for analysis of 11 oxypregnane glycosides from H. gordonii has been developed. The simultaneous analysis of 11 oxypregnane glycosides was achieved with a Phenomenex (Torrance, CA) reversed-phase C18 column using gradient mobile phase of water and acetonitrile, both containing 0.025% trifluoroacetic acid. The developed method was applied to the identification of oxypregnane glycosides in 3 different species of Hoodia and 23 related genera. The HPLC profiles of various plant samples were compared for the presence of oxypregnane glycosides.


Assuntos
Apocynaceae/química , Cromatografia Líquida de Alta Pressão , Glicosídeos/análise , Indicadores e Reagentes , Pregnanos/análise , Padrões de Referência , Soluções , Especificidade da Espécie , Espectrofotometria Ultravioleta
18.
J Chromatogr A ; 1116(1-2): 83-8, 2006 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-16574132

RESUMO

A high-performance liquid chromatography coupled with an evaporative light scattering detector (HPLC-ELSD) has been developed for the simultaneous determination of seven polyoxypregnane glycosides, tenacissosides A, B, G, H, I and marsdenosides C, G, in the stem of Marsdenia tenacissima, a Chinese herbal medicine. With a C18 analytical column, the analytes were separated efficiently using methanol-water as the mobile phase in a gradient program. The method limits of detection ranged from ca. 0.3 microg for marsdenoside C to ca. 0.5 microg for marsdenoside G and the method limits of quantitation from 1.0 microg for marsdenoside C to 1.7 microg for marsdenoside G, respectively. The intra- and inter-day precisions of the method were evaluated and all were less than 4%. All the recoveries for the spiked analytes exceeded 90%. This method was successfully used to analyze 19 samples of the stem of M. tenacissima.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Glicosídeos/análise , Marsdenia/química , Pregnanos/análise , Glicosídeos/química , Luz , Pregnanos/química , Reprodutibilidade dos Testes , Espalhamento de Radiação , Sensibilidade e Especificidade
19.
Rapid Commun Mass Spectrom ; 20(3): 403-11, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16381063

RESUMO

The stems of the Chinese traditional medicine Stephanotis mucronata were screened for immunologically active pregnane glycosides using high-performance liquid chromatography (HPLC) coupled with electrospray ionization tandem mass spectrometry. In the mass spectra of pregnane glycosides, predominant [M+Na]+ ions were observed and used to determine the molecular masses, while fragmentation reactions of the [M+Na]+ ions were recorded to provide information on the primary sequences of oligosaccharide chains in terms of classes of monosaccharide. Fragment ions from the side-chain cleavage of aglycone portions can provide mass information about side-chain substitutions. To further confirm the fragment ion structures, Fourier transform ion cyclotron resonance tandem mass spectrometry (MSn) with low-energy collision-induced dissociation was performed using samples collected from HPLC fractions, which provided accurate elemental compositions of fragment ions. Based on fragmentation patterns and comparison with standards, ten pregnane glycosides were identified as stemucronatosides C, D, F, and G, mucronatosides A, B, and C, stephanoside E, and two glycosides that are identified in the S. mucronata extracts for the first time. The latter two pregnane glycosides are 12-O-cinnamoyldeacetylmetaplexigenin-3-O-6-deoxy-3-O-methyl-beta-D-allopyranosyl-(1 --> 4)-beta-D-cymaropyranosyl-(1 --> 4)-beta-D-cymaropyranoside and 12-O-cinnamoyl-20-O-acetyl (20S)-pregn-6-ene-3beta,5alpha,8beta,12beta,14beta,17beta,20-heptaol 3-O-beta-D-thevetopyranosyl-(1 --> 4)-beta-D-cymaropyranosyl-(1 --> 4)-beta-D-cymaropyranoside.


Assuntos
Glicosídeos/análise , Glicosídeos/imunologia , Caules de Planta/química , Pregnanos/análise , Pregnanos/imunologia , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Glicosídeos/química , Conformação Molecular , Estrutura Molecular , Pregnanos/química , Espectrometria de Massas por Ionização por Electrospray
20.
Gen Comp Endocrinol ; 141(3): 271-81, 2005 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15804514

RESUMO

Gestation and lactation can impose substantial energetic costs on female mammals. We developed a non-invasive means to determine reproductive condition in female giraffe using fecal steroid analysis. Giraffe may be especially challenged during their reproductive cycle because of two characteristics: they are impregnated while lactating and they do not breed seasonally. We studied the social behavior and endocrinology of seven female giraffe in a large naturalistic outdoor enclosure in order to chart connections between maternal physiology and behavior across the reproductive cycle. We found that giraffe gestation averages 448 days among females producing a calf that survived, with fecal pregnane concentrations reaching a zenith during the last trimester of pregnancy. Resumption of ovarian cyclicity following parturition was accelerated after neonatal calf mortality, but ovarian cycles resumed as early as 39 days postparturition while nursing. Although time spent feeding was unaffected by reproductive state, pregnant females significantly reduced time allocated to social behavior and had a tendency to locomote less than when cycling or acyclic. We suggest that modifications in foraging strategies as a function of reproductive state among wild giraffe derive from antipredator activity rather than from metabolic demands. Female giraffe probably cope with simultaneous lactation and gestation by producing high quality milk for neonatal calves commensurate with slow fetal growth and accelerating fetal growth simultaneous with weaning of nursing calves.


Assuntos
Animais de Zoológico/fisiologia , Artiodáctilos/fisiologia , Sistema Endócrino/fisiologia , Pregnanos/metabolismo , Reprodução/fisiologia , Animais , Fezes/química , Feminino , Lactação/fisiologia , Comportamento Materno/fisiologia , Gravidez , Pregnanos/análise , Comportamento Social , Gerenciamento do Tempo , Desmame
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