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Free-living ground squirrel species are sexually dimorphic in hibernation phenology. The underlying causes of these differences are not yet known. Androgens, testosterone (T) in particular, inhibit hibernation. To determine the influence of endogenous androgens on annual timing of hibernation we first measured circulating levels of T and dehydroepiandrosterone (DHEA), an adrenal androgen implicated in non-mating season aggression in other species, in free-living male arctic ground squirrels (Urocitellus parryii, AGS). We also manipulated endogenous androgen levels by surgical castration, and consequently compared body temperature records from intact (n = 24) and castrated (n = 9) males to elucidate the influence of endogenous androgens on annual body temperature cycles. The highest T levels (0.53 ± 0.10 ng/mL) were in reproductively mature male AGS in spring; whereas, both immature males in spring and all males in late summer had T levels an order of magnitude lower (0.07 ± 0.01 and 0.06 ± 0.00 ng/mL, respectively). DHEA levels were higher in males during the late summer compared to reproductively mature males in spring (120.6 ± 18.9 and 35.9 ± 2.3 pg/mL, respectively). Eliminating gonadal androgens via castration resulted in males delaying euthermy by extending heterothermy significantly in spring (Apr 22 ± 2.9) than reproductive males (Mar 28 ± 3.9) but did not change the timing of hibernation onset (castrate: Oct 12 ± 1.0 vs. intact: Oct 3 ± 3.1). We conclude that while androgens play a significant role in spring hibernation phenology of males, their role in fall hibernation onset is unclear.  相似文献   

3.
《Cytokine》2015,74(2):270-276
BackgroundOsteopontin (OPN) is a novel phosphoglycoprotein expressed in Kupffer cells that plays a pivotal role in activating natural killer cells, neutrophils and macrophages. Measuring plasma OPN levels in patients with acute liver failure (ALF) might provide insights into OPN function in the setting of massive hepatocyte injury.MethodsOPN levels were measured using a Quantikine® ELISA assay on plasma from 105 consecutive ALF patients enrolled by the US Acute Liver Failure Study Group, as well as controls including 40 with rheumatoid arthritis (RA) and 35 healthy subjects both before, and 1 and 3 days after undergoing spine fusion (SF) surgery as a model for acute inflammation.ResultsMedian plasma OPN levels across all etiologies of ALF patients were elevated 10- to 30-fold: overall median 1055 ng/mL; range: 33–19,127), when compared to healthy controls (median in pre-SF patients: 41 ng/mL; range 2.6–86.4). RA and SF post op patients had elevated OPN levels (37 ng/mL and 198 ng/mL respectively), well below those of the ALF patients. Median OPN levels were highest in acetaminophen (3603 ng/mL) and ischemia-related ALF (4102 ng/mL) as opposed to viral hepatitis (706 ng/mL), drug-induced liver injury (353 ng/mL) or autoimmune hepatitis (436 ng/mL), correlating with the degree of hepatocellular damage, as reflected by aminotransferase values (R value: 0.47 for AST, p < 0.001).ConclusionsOPN levels appeared to correlate with degree of liver necrosis in ALF. Very high levels were associated with hyperacute injury and good outcomes. Whether OPN exerts a protective effect in limiting disease progression in this setting remains uncertain.  相似文献   

4.
《Harmful algae》2011,10(6):557-562
Two species of Kareniaceae, Karlodinium veneficum (Swan and Huon River isolates) and Karlodinium conicum, and their respective purified karlotoxins (KmTx), were investigated for ichthyotoxicity on larval sheepshead minnow. Two non-karlotoxin producing species, Karenia mikimotoi and Karlodinium ballantinum were also tested. Algal treatments included live and lysed cells (homogenized and CuSO4 treated) with fish mortalities observed from lysed Ka. veneficum and Ka. conicum but none observed from K. mikimotoi and Ka. ballantinum. The variance in ichthyotoxicity between live and lysed cells of Ka. veneficum (Swan and Huon River) and Ka. conicum (Southern Ocean) confirm that toxin is cell bound and ichthyotoxicity increases upon lysis. Ichthyotoxic blooms of Ka. veneficum in situ in the Swan River, Western Australia and Chesapeake Bay, Maryland, USA are unrelated to algal cell density as mortality was observed with low densities. In laboratory treatments, no fish mortalities were observed upon exposure to live intact cells of all four species at algal concentrations up to 2.5 × 105 cells/mL in replete nutrient growth conditions. Lysed low density (3 × 104 cells/mL) Ka. veneficum (Swan and Huon River) grown under P-limited nutrients caused quicker fish mortality than those cultured in replete nutrient conditions. Pure toxin isolated from Ka. veneficum (Swan and Huon River) and Ka. conicum (Southern Ocean) were toxic to sheepshead minnow larvae, with the lethal dose lowest for KmHuonTx 2 (508.2 ng/mL), followed by KmSwanTx 2-1 (563.2 ng/mL), and KmconicumTx (762.4 ng/mL).  相似文献   

5.
The body composition of Nile tilapia (Oreochromis niloticus) collected from drainage canals in Al-Ahsa, Saudi Arabia and the concentration of four heavy metals; zinc (Zn), cadmium (Cd), cobalt (Co) and lead (Pb) in both fish muscles and the water collected from this environment were assessed across the four seasons. The body composition was found to change with the seasons, with the best body composition being recorded in autumn and winter, where higher levels of protein (17.24, 17.65%), and fat (0.58, 0.71%) and lower water content (80.15, 79.86%) respectively were noted. The concentration of heavy metals in both fish muscles and the water body also varied significantly with the seasons. In the fish muscles, the highest content of Zn (0.409 mg/kg dry weight) and Cd (4.140 mg/kg dry weight) was recorded in winter, however, the highest concentration of Co (0.318 mg/kg dry weight) and Pb (1.96 mg/kg dry weight) was observed in spring and summer respectively. On the other hand, the water samples collected in autumn showed the maximum concentration of Cd (1.385 mg/L), Co (0.762 mg/L) and Pb (0.18 mg/L) however, the maximum concentration of Zn (0.0041 mg/L) was recorded in winter. With the exception of Cd, the accumulation of the studied heavy metals in fish muscles was within the safe limits for seafood recommended by various organizations.  相似文献   

6.
《Small Ruminant Research》2007,68(2-3):257-263
Prostaglandin E2 has been shown to increase the ovine embryo hatching rate, and PGF to reduce the development of rabbit, bovine, and rat embryos. The objective was to determine the effects of PGE2 and PGF on development of caprine embryos. Estrus was synchronized in does (n = 25) with medroxyprogesterone acetate (MAP) intravaginal sponges for 12 days, and superovulated with 20 units of FSH. On day 6 following estrus, embryos were flushed (n = 128) and incubated individually per well in 25 μl droplets of TCM-199 and BSA (8 mg/ml) for 6 days at 38.5 °C in a 5% CO2: air with one of the following treatments: (1) control (0.0002% EtOH), (2) PGE2 (7 ng/ml), (3) PGF (7 ng/ml), (4) low PGE2:high PGF (3.5 ng/ml:14 ng/ml), (5) balanced PGE2:PGF (7 ng/ml:7 ng/ml), or (6) high PGE2:low PGF (14 ng/ml:3.5 ng/ml). Treatment with PGE2 alone reduced (P < 0.05) the hatching rate (1/15; 7%). The hatching rate of embryos treated with PGF alone (9/18; 50%), low PGE2:high PGF (8/16; 50%), and balanced PGE2:PGF (11/16; 69%) were similar to control (6/18; 33%). In contrast, the hatching rate was non-significantly increased (13/18; 72%) with the high PGE2:low PGF treatment. None of the treatments affected development from the morula to blastocyst stage. From the current data, it can be concluded that PGE2 alone reduced hatching rate, and PGF alone had no effect on the development of caprine embryos. High concentrations of PGE2 with PGF improved the hatching rates. Thus, uterine concentrations of PGE2 may need to reach a threshold level to improve embryo hatching, as previously reported, while increased uterine concentrations of PGF during early pregnancy would not affect development of the embryo.  相似文献   

7.
A rapid method has been developed to analyse for firocoxib (FIRO) residue in bovine milk. Milk samples were extracted with acetonitrile and sample extracts were purified on Evolute? ABN solid phase extraction cartridges. Aliquots were analysed by rapid resolution liquid chromatography tandem mass spectrometry (RRLC–MS/MS). The method was validated in bovine milk, according to the criteria defined in Commission Decision 2002/657/EC. The decision limit (CCα) was 1.18 ng/mL and for the detection capability a (CCβ) value of 2.02 ng/mL was obtained. The measurement uncertainty of the method was 27%. Fortifying bovine milk samples (n = 18) in three separate assays, show the accuracy of the method to be between 96 and 105%. The precision of the method, expressed as RSD values for the within-lab reproducibility at the three levels of fortification (5, 7.5 and 10 ng/mL) was less than 11% respectively.  相似文献   

8.
《Small Ruminant Research》2010,88(1-3):64-69
This study was done to verify if the lack of increase of milk fat content observed in Alpine dairy goats under once daily milking (ODM) compared to twice daily milking (TDM), results from disturbances of animals and/or milk ejection reflex. In this respect, we determined the milk yield and composition in the same 12 multiparous Alpine dairy goats when they were managed first under TDM (period 1: P1) and then under ODM (period 2: P2). Furthermore, oxytocin (OT) and cortisol (CORT) releases and milk emission kinetic of these goats were measured at morning milking 2 and 4 times in P1 and P2, respectively.ODM compared to TDM, caused 18 and 23% reductions, respectively in daily milk yield and milk fat content without milk protein content modification.Although baseline concentration of blood OT was lower under ODM than TDM management (7.0 pg/mL vs 17.8 ± 2.0 pg/mL, respectively), ODM did not modify the total amount of OT released during milking (15,484 pg/mL/32 min vs 18,996 ± 2865.3 pg/mL/32 min, respectively), the peak concentration of OT (57.2 pg/mL vs 73.6 ± 10.5 pg/mL, respectively) or the time to reach it (3.0 min vs 2.0 ± 0.5 min, respectively) by comparison to TDM.ODM compared to TDM, never modified the baseline concentrations of CORT (6.1 ng/mL vs 7.1 ± 1.1 ng/mL, respectively), the total amount of CORT released (11,727 ng/mL/32 min vs 10,073 ± 1522.2 ng/mL/32 min, respectively), the peak concentrations of CORT (16.1 ng/mL vs 15.1 ± 2.1 ng/mL, respectively) and the time to reach it (13.1 min vs 11.0 ± 1.5 min).During ODM, milk flow latency was reduced (−61%) while the mean flow rate was increased (+28%) by comparison to TDM. ODM compared to TDM management, did not modify the maximum flow rate (1.6 L/min vs 1.6 ± 0.2 L/min, respectively) or the time to reach this maximum (103.0 s vs 95.0 ± 10.0 s, respectively). The total milking duration at morning milking was not different (250.0 s vs 221.0 ± 22.0 s, respectively) although the morning milk yield was significantly higher under ODM management (2.63 kg/d vs 1.87 ± 0.1 kg/d, respectively).This results show that milk emission is improved under ODM management in Alpine goats without inhibition or disturbance of neuro-hypophyseal OT release pattern and lack of activation of the hypothalamic–pituitary–adrenal axis and plasma cortisol increase, disproving our initial hypotheses of a disturbance of animals and/or incomplete milk ejection to explain the low fat content of milk under ODM in this breed.  相似文献   

9.
For the first time, a highly sensitive and simple LC–MS/MS method after one-step precipitation was developed and validated for the simultaneous determination of paracetamol (PA), pseudoephedrine (PE), dextrophan (DT) and chlorpheniramine (CP) in human plasma using diphenhydramine as internal standard (IS). The analytes and IS were separated on a YMC-ODS-AQ C18 Column (100 mm × 2.0 mm, 3 μm) by a gradient program with mobile phase consisting of 0.3% (v/v) acetic acid and methanol at a flow rate of 0.30 mL/min. Detection was performed on a triple quadrupole tandem mass spectrometer via electrospray ionization in the positive ion mode. The method was validated and linear over the concentration range of 10–5000 ng/mL for PA, 2–1000 ng/mL for PE, 0.05–25 ng/mL for DT and 0.1–50 ng/mL for CP. The accuracies as determined from quality control samples were in range of ?8.37% to 3.13% for all analytes. Intra-day and inter-day precision for all analytes were less than 11.54% and 14.35%, respectively. This validated method was successfully applied to a randomized, two-period cross-over bioequivalence study in 20 healthy Chinese volunteers receiving multicomponent formulations containing 325 mg of paracetamol, 30 mg of pseudoephedrine hydrochloride, 15 mg of dextromethorphan hydrobromide and 2 mg of chlorphenamine maleate.  相似文献   

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11.
《Endocrine practice》2014,20(3):236-243
ObjectiveTo assess whether 25-hydroxyvitamin D (25[OH]D) deficiency is a risk factor for chronic kidney disease (CKD) in ambulatory indigent patients.MethodsData for all serum 25(OH)D concentrations measured during 2010 in our ambulatory nondialysis-dependent patients were analyzed along with CKD-related parameters. Patients were stratified into groups based on 25(OH)D levels of < 10, 10 to 19, 20 to 29, and ≥ 30 ng/mL. CKD was defined by estimated glomerular filtration rate (eGFR; Chronic Kidney Disease-Epidemiology Collaboration [CKD-EPI] equation) and abnormal urine protein to creatinine ratios. CKD-associated parameters included serum parathyroid hormone (PTH), 1,25-dihydroxyvitamin D (1,25[OH]2D), alkaline phosphatase, albumin, corrected calcium, and total CO2 levels.ResultsA total of 2,811 patients had 25(OH)D levels measured. Patients with 25(OH)D levels < 10 ng/mL had significantly increased relative risk (RR) of an eGFR < 15 mL/min/1.73 m2 (RR, 4.0), an eGFR of 15 to 29 mL/min/1.73 m2 (RR, 2.6), urine protein to creatinine ratio > 3.5 g/g (RR, 5.6), and serum PTH > 100 pg/mL (RR, 2.8) compared to patients with a 25(OH)D level ≥ 30 ng/mL. Patients with 25(OH)D levels of 10 to19 ng/mL had significantly increased RR of a urine protein to creatinine ratio > 3.5 g/g (RR,4.8) and serum PTH > 100 pg/mL (RR, 1.5) compared to patients with 25(OH)D levels ≥ 30 ng/mL.Conclusion25(OH)D deficiency (< 10 ng/mL) was associated with reduced eGFR, nephrotic-range proteinuria, and increased PTH levels in our population of ambulatory urban indigent patients. (Endocr Pract. 2014;20:236-243)  相似文献   

12.
Background & aims: The aim of this study was to investigate the clinical characteristics and pathophysiology of drug-induced liver injury (DILI) – acute liver failure (ALF). Methods: The patients with acute liver injury (ALI) including ALF from 2009 to 2014 were analyzed. The hepatic encephalopathy (HE) development rate was compared with the findings from a national survey in Japan. The serum cytokines levels and the findings of a liver function test were evaluated in the DILI patients. Results: The HE development rate substantially decreased for autoimmune hepatitis (AIH) – and undetermined cause-induced ALI owing to the early prediction system, but not in DILI-ALI. Among the DILI-ALF and AIH-ALF cases, the CK-18 fragment (1480.1 U/L, 3945.4 U/L), IL-8 (82.9 pg/mL, 207.5 pg/mL), IP-10 (1379.6 pg/mL, 3731.2 pg/mL) and MIP-1β (1017.7 pg/mL, 2273.3 pg/mL) levels were lower in the DILI-ALF cases. Among the DILI-ALI and DILI-ALF cases, IL-4 (19.8 pg/mL, 25.4 pg/mL) and RANTES (14028.0 pg/mL, 17804.7 pg/mL) were higher in DILI-ALI, and HMGB-1 (397.1 pg/μL, 326.2 pg/μL) and HGF (2.41 ng/mL, 0.55 ng/mL) were higher in DILI-ALF. We observed that HGF independently associated with DLI-ALF development. Conclusions: Despite the low grade apoptosis and inflammation, DILI patients progressed to ALF comparable with that of the AIH patients.  相似文献   

13.
Beginning in April 2002, three species of Florida puffer fish from around the state of Florida, USA were monitored for the presence of saxitoxin (STX). In total, 873 southern (Sphoeroides nephelus), 171 checkered (S. testudineus), and 53 bandtail (S. spengleri) puffer fish were collected between 2002 and 2006 from eight regions: Jacksonville, the Indian River Lagoon, Tequesta, the Florida Keys, Charlotte Harbor, Tampa Bay, Cedar Key, and Apalachicola. Emphasis was placed on collecting specimens from the Indian River Lagoon (IRL), where recreational harvesting of puffer fish led to 28 cases of saxitoxin puffer fish poisoning (SPFP) between January 2002 and May 2004. Southern puffer fish from the northern IRL routinely contained the highest concentrations of STX, with average levels in the skin of 1787 μg STXequiv./100 g tissue. Elevated concentrations were also found in the muscle (1102 μg STXequiv./100 g), gut contents (539 μg STXequiv./100 g), gonads (654 μg STXequiv./100 g), and liver (214 μg STXequiv./100 g). Lower, yet significant (above the action limit of 80 μg STXequiv./100 g tissue), concentrations of STX were also detected in the skin (599 μg STXequiv./100 g), muscle (233 μg STXequiv./100 g), gut contents (197 μg STXequiv./100 g), and gonads (239 μg STXequiv./100 g) of southern puffer fish from Tequesta in the southern IRL, as well as in the gonads (122 μg STXequiv./100 g) of Jacksonville southern puffer fish and the skin (265 μg STXequiv./100 g) of Tampa Bay southern puffer fish. STX concentrations above the action limit were also found in the skin of bandtail puffer fish from the IRL (620 μg STXequiv./100 g), Tequesta (374 μg STXequiv./100 g), and the Florida Keys (230 μg STXequiv./100 g). Checkered puffer fish collected from the IRL, Tequesta, and the Florida Keys on average were nontoxic, containing STX levels below the action limit in all tissues.  相似文献   

14.
A high throughput and specific method using ultra performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS) was developed for the simultaneous determination of diltiazem and its two metabolite (N-desmethyldiltiazem and O-desacetyldiltiazem) in human plasma. A one-step liquid–liquid extraction (LLE) with methyl-t-butyl ether (MTBE) involved for the extraction of diltiazem (DLTZ), metabolites (DMeD and DAcD) and internal standard. Analytes were chromatographed on a ACQUITY UPLC? BEH C18 column (100 mm × 2.1 mm, i.d., 1.7 μm) with isocratic elution at a flow rate of 0.2 mL/min using 10 mM ammonium acetate buffer–acetonitrile (25:75, v/v). The Quattro Premier XE LC–MS/MS was operated under the multiple reaction-monitoring mode (MRM) using the electrospray ionization technique. Using 300 μL plasma, the method was validated over the concentration range 0.48–639.9 ng/mL for DLTZ and 0.24–320.1 for DMeD and 0.24–320.7 ng/mL for DAcD, with a lower limit of quantification of 0.48 ng/mL for DLTZ and 0.24 ng/mL for metabolites. The intra- and inter-day precision and accuracy were within 10.0%. The recovery was 77.4%, 76.0%, 74.5% and 74.1% for DLTZ, DMeD, DAcD and Ziprasidone, respectively. Total run time was 2.0 min only.  相似文献   

15.
A study was conducted to elucidate hormonal control of leptin receptor gene expression in primary cultures of porcine hepatocytes. Hepatocytes were isolated from swine and seeded into T-25 flasks. Cultures were established in medium containing fetal bovine serum for one day and switched to serum-free medium (William's E medium and 1 ng/mL insulin) for the remainder of the 3 d culture period. For the final 24 h, medium was supplemented with porcine growth hormone (GH, 100 or 500 ng/mL), insulin-like growth factor 1 (IGF-1, 50 to 250 ng/mL) or triiodothyronine (T3, 100 ng/mL). RNA was extracted and relative quantitative RT-PCR was performed with primers for long form leptin receptor. Receptor expression was calculated relative to 18S rRNA. Insulin had no effect (P > 0.05), while T3 increased leptin receptor mRNA abundance (P < 0.05). Treatment with GH or IGF-I reduced leptin receptor expression (P < 0.05). Phosphorylation of ERK1/2 in response to acute leptin treatment was inhibited by previous exposure to GH or IGF-I. Hepatocytes secreted IGF-I under basal conditions and this was enhanced by GH addition. These data suggest porcine hepatocytes may be less sensitive to leptin stimulation due to the actions of endogenous IGF-I on leptin receptor expression.  相似文献   

16.
The catechin, epigallocatechin gallate (eGCG), found in green tea, has inhibitory activity against a number of protein toxins and was investigated in relation to its impact upon ricin toxin (RT) in vitro. The IC50 for RT was 0.08 ± 0.004 ng/mL whereas the IC50 for RT + 100 μM eGCG was 3.02 ± 0.572 ng/mL, indicating that eGCG mediated a significant (p < 0.0001) reduction in ricin toxicity. This experiment was repeated in the human macrophage cell line THP-1 and IC50 values were obtained for RT (0.54 ± 0.024 ng/mL) and RT + 100 μM eGCG (0.68 ± 0.235 ng/mL) again using 100 μM eGCG and was significant (p = 0.0013). The documented reduction in ricin toxicity mediated by eGCG was found to be eGCG concentration dependent, with 80 and 100 μg/mL (i.e. 178 and 223 μM respectively) of eGCG mediating a significant (p = 0.0472 and 0.0232) reduction in ricin toxicity at 20 and 4 ng/ml of RT in Vero and THP-1 cells (respectively). When viability was measured in THP-1 cells by propidium iodide exclusion (as opposed to the MTT assays used previously) 10 ng/mL and 5 ng/mL of RT was used. The addition of 1000 μM and 100 μM eGCG mediated a significant (p = 0.0015 and < 0.0001 respectively) reduction in ricin toxicity relative to an identical concentration of ricin with 1 μg eGCG. Further, eGCG (100 μM) was found to reduce the binding of RT B chain to lactose-conjugated Sepharose as well as significantly (p = 0.0039) reduce the uptake of RT B chain in Vero cells. This data suggests that eGCG may provide a starting point to refine biocompatible substances that can reduce the lethality of ricin.  相似文献   

17.
The analysis of pegylated-interferon-α2a in patient serum samples is of high interest for clinic research trials, as this therapeutic protein has become an important antiviral treatment. In this study, an LC–MS/MS method for the absolute quantification of pegylated-interferon-α2a in human serum was developed. The assay achieved a lower limit of quantification of 3.6 ng/mL (60 pM) with the use of a monolithic C18 solid phase extraction to enrich the target protein. The linear range of the assay was defined up to 54 ng/mL to measure the typical clinical pegylated-interferon-α2a levels, and within this range, the precision and accuracy were found to be within ±20%. The method was applied to a clinical study and found suitable for high-throughput analysis of pegylated-interferon-α2a in human serum. In addition, further investigations suggested the enrichment step may have general application to the sensitive analysis of other low molecular weight proteins.  相似文献   

18.
A rapid 2 min liquid chromatography–tandem mass spectrometry (LC–MS/MS) method operating in multiple reaction ion monitoring mode was developed and validated that allows for the characterization and simultaneous quantification of 11 phytoestrogen metabolites with mass transitions m/z 241/119 (equol), 253/132 (daidzein), 255/149 (dihydrodaidzein), 257/108 (O-desmethylangolesin), 269/133 (genistein), 283/184 (glycitein), 267/191 (formononetin), 289/109 (biochanin A), 267/91 (coumestrol), enterodiol (301/253), and enterolactone (297/253). The method was demonstrated to be specific and sensitive, and a linear response for each phytoestrogen was observed over a range of 1–5000 ng/mL in human serum with the exception of dihydrodaidzein, whose lower limit of quantification was 2 ng/mL. The separation was carried out on a Synergi Polar-RP 2.5 micron (50 mm × 2.0 mm i.d.) column at 50 °C with water and acetonitrile (both containing 10 mM ammonium acetate) as the mobile phase under gradient conditions at a flow rate of 0.75 mL/min. This LC–MS/MS method is very useful for high-throughput analysis of phytoestrogens and proved to be simple, sensitive, reproducible, and reliable.  相似文献   

19.
The 3α,5α- and 3α,5β-reduced derivatives of progesterone, deoxycorticosterone, dehydroepiandrosterone and testosterone enhance GABAergic neurotransmission and produce inhibitory neurobehavioral and anti-inflammatory effects. Despite substantial information on the progesterone derivative (3α,5α)-3-hydroxypregnan-20-one (3α,5α-THP, allopregnanolone), the physiological significance of the other endogenous GABAergic neuroactive steroids has remained elusive. Here, we describe the validation of a method using gas chromatography–mass spectrometry to simultaneously identify serum levels of the eight 3α,5α- and 3α,5β-reduced derivatives of progesterone, deoxycorticosterone, dehydroepiandrosterone and testosterone. The method shows specificity, sensitivity and enhanced throughput compared to other methods already available for neuroactive steroid quantification. Administration of pregnenolone to rats and progesterone to women produced selective effects on the 3α,5α- and 3α,5β-reduced neuroactive steroids, indicating differential regulation of their biosynthetic pathways. Pregnenolone administration increased serum levels of 3α,5α-THP (+1488%, p < 0.001), (3α,5α)-3,21-dihydroxypregnan-20-one (3α,5α-THDOC, +205%, p < 0.01), (3α,5α)-3-hydroxyandrostan-17-one (3α,5α-A, +216%, p < 0.001), (3α,5α,17β)-androstane-3,17-diol (3α,5α-A-diol, +190%, p < 0.01). (3α,5β)-3-hydroxypregnan-20-one (3α,5β-THP) and (3α,5β)-3-hydroxyandrostan-17-one (3α,5β-A) were not altered, while (3α,5β)-3,21-dihydroxypregnan-20-one (3α,5β-THDOC) and (3α,5β,17β)-androstane-3,17-diol (3α,5β-A-diol) were increased from undetectable levels to 271 ± 100 and 2.4 ± 0.9 pg ± SEM, respectively (5/8 rats). Progesterone administration increased serum levels of 3α,5α-THP (+1806%, p < 0.0001), 3α,5β-THP (+575%, p < 0.001), 3α,5α-THDOC (+309%, p < 0.001). 3α,5β-THDOC levels were increased by 307%, although this increase was not significant because this steroid was detected only in 3/16 control subjects. Levels of 3α,5α-A, 3α,5β-A and pregnenolone were not altered. This method can be used to investigate the physiological and pathological role of neuroactive steroids and to develop biomarkers and new therapeutics for neurological and psychiatric disorders.  相似文献   

20.
Sesquiterpenes, arecoic acids A–F and arecolactone, were isolated from the ethyl acetate extracts of the fermented broth of Arecophila saccharicola YMJ96022401 along with two known analogues 1,7α,10α-trihydroxyeremophil-11(13)-en-12,8-olide and 1,10α,13-trihydroxyeremophil-7(11)-en-12,8-olide. Their structures were elucidated on the basis of spectroscopic data analyses. The inhibitory effects of all of these compounds on nitric oxide (NO) production in lipopolysaccharide (LPS, 200 μg/mL)-activated murine macrophage RAW264.7 cells were also evaluated. Among these compounds, 1,7α,10α-trihydroxyeremophil-11(13)-en-12,8-olide significantly inhibited NO production without any cytotoxicity, and its average maximum inhibition (Emax) at 100 μM and median inhibitory concentration (IC50) were 85.7% ± 0.8% and 16.5 ± 1.0 μM, respectively. Arecolactone was the most potent, with the Emax at 12.5 μM and IC50 being 94.7% ± 0.8% and 1.32 ± 0.1 μM, respectively, but displayed cytotoxicity at considerable higher concentrations than 25 μM. Analyses of Western blotting indicated that arecolactone (0.8–12.5 μM) inhibited induction of inducible NO synthase (iNOS) by LPS, which involved suppression of NF-κB activation and the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun NH(2)-terminal kinase (JNK) and p38 mitogen-activated protein kinases (MAPKs) in activated RAW 264.7 cells. In addition, arecolactone concentration-dependently prevented the vascular hyporeactivity to phenylephrine induced by LPS (300 ng/mL) through iNOS pathway in isolated rat thoracic aortic rings. These results indicated that both of these naturally occurring iNOS inhibitors may provide a rationale for the potential anti-inflammatory effect of A. saccharicola YMJ96022401.  相似文献   

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