Sterols of the unicellular algae Nematochrysopsis roscoffensis and Chrysotila lamellosa: isolation of (24E)-24-n-propylidenecholesterol and 24-n-propylcholesterol

Two rare C₃₀-sterols, (24E)-24-n-propylidenecholest-5-en-3β-ol and 24-n-propylcholest-5-en-3β-ol, and (24S)-24-ethylcholesta-5,22-dien- 3β-ol (stigmasterol) are the major sterols of Nematochrysopsis roscoffensis, a Chrysophyte of the Sarcinochrysidales order. This unique sterol composition is different from the sterol contents of other Chrysophytes and justifies the peculiar position of the Sarcinochrysidales, which are by some characteristics morphologically and biologically related to the Phaeophyceae. The presence of (24S)-24-methylcholesta-5,22-dien-3β-ol (24-epibrassicasterol) as a major sterol in Chrysotila lamellosa is in accordance with the few previous results obtained from other Prymnesiophyceae, although the presence of the other major sterol, (24R)-24-ethylcholesta-5,22-dien-3β-ol (poriferasterol) has never been reported in these algae.     

Interactions of adrenocorticotropic hormone with its adrenal receptors. Degradation of ACTH-1-24 and ACTH-11-24.

Crude membranes (20,000 times g pellet) prepared from human, rat, and ovine adrenals bind 125-I-corticotropin-(1-24)-tetracosapeptide (125-I-ACTH-1-24) and degrade unbound hormone. The degradation is dependent on temperature and the concentration of membrane proteins. The degradation of 125-I-[9-tryptophan(o-nitrophenylsulfenyl)]-corticotropin-(1-24)-tetracosapeptide (125-I-NPS-ACTH-1-24) is similar to 125-I-ACTH-1-24, but that of 125-I-corticotropin-(11-24)-tetradecapeptide (125-I-ACTH-1-24 is inhibited by ACTH-1-24 and corticotropin-(1-10)-decapeptide (ACTH-1-10), but ACTH-11-24 at the same molar concentration has no effect. On the other hand, the degradation of 125-I-ACTH-11-24 is protected by ACTH-11-24 and ACTH-1-24, but not by ACTH-1-10. This suggests two systems of degradation, one will have the NH-2-terminal sequence of ACTH-1-24 as substrate, and the other the 11-24 COOH-terminal sequence. The main label product from the degradation of the 125-I-ACTH-1-24 and 125-I-ACTH-11-24 behaves as [125-I]monoiodotyrosine on Sephadex G-50 and paper chromatography. The independence of ACTH binding to its receptor and degradation is demonstrated by the following facts. (a) Calcium and pancreatic trypsin inhibitor completely inhibit the binding at concentrations when the degradation is not altered; (b) the sequences of peptides of ACTH which inhibit the binding and degradation of 125-I-ACTH-1-24 are different.     

Bone resorbing activities of 24-hydroxy stereoisomers of 24-hydroxyvitamin D3 and 24,25-dihydroxyvitamin D3.

R and S isomers of 24-OH-D₃ and 24,25-(OH)₂D₃ were tested for their effects on bone resorption $\text{in vitro}$. 24(R), 25-(OH)₂D₃ was more active than 24(S),25-(OH)₂D₃. Likewise, 24(R)-OH-D₃ was more active than 24(S)-OH-D₃. The bone resorbing activity of 24(R)-OH-D₃ was equivalent to that of 25-OH-D₃; 24(R),25-(OH)₂D₃ was somewhat less potent. The results indicate that there is discrimination between the isomers of these compounds at the level of the responding tissue.     

Adverse effects of fullerenes on endothelial cells: fullerenol C60(OH)24 induced tissue factor and ICAM-I membrane expression and apoptosis in vitro

We studied the effects of a C60 water suspension at 4 microg/mL (nC60) and the water soluble fullerenol C60(OH)24 at final concentrations of 1-100 microg/mL on human umbilical vein endothelial cells (HUVECs) in culture. We found that a 24 hr treatment of HUVECs with C60(OH)24 at 100 microg/mL significantly increased cell surface expression of ICAM-1(CD54) (67 +/- 4% CD54+ cells vs. 19 +/- 2 % CD540 cells in control; p < 0.001). In addition, this treatment induced the expression of tissue factor (CD142) on HUVECs (54 +/- 20% CD142+ cells vs 4 +/- 2% CD142+ cells in control; p = 0.008) and increased exposure of phosphatidylserine (PS) (29 +/- 2% PS+ cells vs. 12 +/- 5% PS+ cells in control; p < 0.001). Analysis of cell cycle and DNA fragmentation (TUNEL) showed that both nC60 and C60(OH)24 caused G1 arrest of HUVECs and C60(OH)24 induced significant apoptosis (21 +/- 2% TUNEL+ cells at 100 microg/mL of C60(OH)24 vs. 4 +/- 2% TUNEL+ cells in control; p < 0.001). We also demonstrated that both nC60 and C60(OH)24 induced a rapid concentration dependent elevation of intracellular calcium [Ca2+]i. This could be inhibited by EGTA, suggesting that the source of [Ca2+]i in fullerene stimulated calcium flux is predominantly from the extracellular environment. In conclusion, fullerenol C60(OH)24 had both pro-inflammatory and pro-apoptotic effects on HUVECs, indicating possible adverse effects of fullerenes on the endothelium.     

Chemical synthesis, spectral properties, and chromatography of 4alpha-methyl and 4beta-methyl isomers of (24R)-24-ethyl-5alpha-cholestan-3beta-ol and (24S)-24-ethyl-cholesta-5,22-dien-3beta-ol.

Described herein are chemical syntheses of the following compounds: 4-methyl-(24S)-24-ethyl-cholesta-4,22-dien-3-one, 4,4-dimethyl-(24S)-24-ethyl-cholesta-5,22-dien-3-one, 4beta-methyl-(24R)-24-ethyl-5alpha-cholestan-3beta-ol, 4alpha-methyl-(24R)-24-ethyl-5alpha-cholestan-3beta-ol, 4alpha-methyl-(24S)-24-ethyl-5alpha-cholest-22-en-3beta-ol, 4-methyl-6beta-bromo-(24S)-24-ethyl-cholesta-4,22-dien-3-one, 4alpha-methyl-(24S)-24-ethyl-cholesta-5,22-dien-3beta-ol, 4alpha,5alpha-epoxy-(24S)-24-ethyl-cholesta-4,22-dien-3beta-yl acetate, 4beta-methyl-(24S)-24-ethyl-cholest-22-en-3beta,5alpha-diol, 4beta-methyl-5alpha-hydroxy-(24S)-24-ethyl-cholest-22-en-3beta-yl acetate, 4beta-methyl-(24S)-24-ethyl-cholesta-5,22-dien-3beta-yl acetate and 4beta-methyl-(24S)-24-ethyl-cholesta-5,22-dien-3beta-ol. Chromatographic, nuclear magnetic resonance, and mass spectral data are presented for the compounds under consideration.     

Triterpenoid saponins and acylated prosapogenins from Harpullia austro-caledonica

Three new triterpenoid saponins have been isolated from the stem bark of Harpullia austro-caledonica and identified as 24-O-[alpha-L-rhamnopyranosyl-(1->2)-beta-D-glucopyranosyl]-28-O-[beta-D-glucopyranosyl-(1->2)-beta-D-glucopyranosyl]-protoaescigenin, 24-O-[alpha-L-rhamnopyranosyl-(1->2)-beta-D-glucopyranosyl]-28-O-[beta-D-glucopyranosyl-(1->2)-beta-D-glucopyranosyl]-16-desoxyprotoaescigenin, 24-O-[alpha-L-rhamnopyranosyl-(1->2)-beta-D-glucopyranosyl]-28-O-[beta-D-glucopyranosyl-(1->2)-beta-D-glucopyranosyl]-24-oxo-camelliagenin D. The 21,22-di-O-angeloate esters of protoaescigenin and barringtogenol C were isolated in the acid hydrolysate of the saponin extract together with a new prosapogenin identified as 21beta,22alpha-di-O-angeloyl camelliagenin D. The structures were established using one- and two- dimensional NMR and mass spectrometry.     

Transcript profiling and lipidomic analysis of ceramide subspecies in mouse embryonic stem cells and embryoid bodies

Ceramides (Cers) are important in embryogenesis, but no comprehensive analysis of gene expression for Cer metabolism nor the Cer amounts and subspecies has been conducted with an often used model: mouse embryonic stem cells (mESCs) versus embroid bodies (EBs). Measuring the mRNA levels by quantitative RT-PCR and the amounts of the respective metabolites by LC-ESI/MS/MS, notable differences between R1 mESCs and EBs were: EBs have higher mRNAs for CerS1 and CerS3, which synthesize C18- and C≥24-carbons dihydroceramides (DH)Cer, respectively; EBs have higher CerS2 (for C24:0- and C24:1-); and EBs have lower CerS5 + CerS6 (for C16-). In agreement with these findings, EBs have (DH)Cer with higher proportions of C18-, C24- and C26- and less C16-fatty acids, and longer (DH)Cer are also seen in monohexosylCers and sphingomyelins. EBs had higher mRNAs for fatty acyl-CoA elongases that produce C18-, C24-, and C26-fatty acyl-CoAs (Elovl3 and Elovl6), and higher amounts of these cosubstrates for CerS. Thus, these studies have found generally good agreement between genomic and metabolomic data in defining that conversion of mESCs to EBs is accompanied by a large number of changes in gene expression and subspecies distributions for both sphingolipids and fatty acyl-CoAs.     

Stereochemical aspects of the biosynthesis of the side chain of 9beta, 19-cyclopropyl sterols in maize seedlings treated with tridemorph

9β, 19-Cyclopropyl sterols such as 24-methyl pollinastanol accumulate dramatically in maize (Zea mays L. var LG 11) seedlings treated with Tridemorph (2,6-dimethyl-N-tridecyl-morpholine), a systemic fungicide (M. Bladocha, P. Benveniste, Plant Physiol 1983 41: 756-762). In contrast to the situation in control plants where 24-ethyl sterols predominate largely, 24-methyl sterols were more than 98% of total cyclopropyl sterols. In addition, 24-methyl cyclopropyl sterols were a mixture of (24-R)- and (24-S)-24-methyl epimers and are similar in that respect to the 24-methyl cholesterol of control plants. The presence of two epimers at C-24 has been previously explained by the operation of two routes (M. Zakelj, L. J. Goad, Phytochemistry 1983 22: 1931-1936). One may proceed via Δ²⁴⁽²⁸⁾- and Δ²⁴⁽²⁵⁾-sterols to produce the (24-R)-24-methyl epimer. The other route may involve reduction of either a Δ²⁴⁽²⁸⁾-, a Δ²³-, or a Δ²⁵-sterol intermediate to give the (24-S)-24-methyl epimer. Such intermediates have been searched for in excised Zea mays axes grown aseptically in the presence of Tridemorph and either [5-¹⁴C]mevalonic acid, or [Me-¹⁴C]-l-methionine. Whereas Δ²⁴⁽²⁸⁾- and Δ²⁴⁽²⁵⁾-cyclopropyl sterols were found in relatively large amounts, only traces of radioactivity were associated with Δ²⁵-sterols. Gas chromatography/mass spectrometry analysis of the sterols from axes grown in the presence of [Me-²H₃]-l-methionine showed that Δ²⁴⁽²⁸⁾-cyclopropyl sterols contained only two ²H atoms at C-28 as expected and that the 24-methyl pollinastanol fraction contained species with two ²H atoms and no species with three ²H atoms. These results indicate that both (24-R)- and (24-S)-epimers originate from a common Δ²⁴⁽²⁸⁾ precursor. After incubation of the axis with [5-¹⁴C,(4-R)-4-³H₁]mevalonic acid, the 24-methyl pollinastanol had a ³H:¹⁴C atomic ratio of 4:6 which is consistent with the intermediacy of a Δ²⁴⁽²⁵⁾-sterol. All these data are in accordance with a pathway where Δ²⁴⁽²⁸⁾-cyclopropyl sterols are isomerized to give Δ²⁴⁽²⁵⁾-cyclopropyl sterols which in turn would be reduced nonregiospecifically to yield both (24-R)- and (24-S)-24-methyl pollinastanols. A plausible mechanism for the reduction step is discussed.     

Comparing Glaucoma Progression on 24-2 and 10-2 Visual Field Examinations

PurposeTo compare the rate of mean deviation (MD) change on 24-2 versus 10-2 VFs in treated glaucomatous eyes with 5 or more examinations.MethodsIn a retrospective study, 24-2 and 10-2 VFs of 131 glaucoma patients (167 eyes) who had undergone at least 5 VFs examinations during their follow-up were analyzed. All these patients had VF defects both on 24-2 and 10-2 VFs. Rates of MD change were calculated using best linear unbiased predictions (BLUP).ResultsMedian age, MD on 24-2 VF at baseline, number of VFs performed during follow-up and follow-up duration were 55 years, -16.9 dB, 9 and 9 years respectively. Median rate of MD change was significantly greater (p<0.001) on 10-2 VF (-0.26 dB/year; interquartile range [IQR]: -0.47, -0.11) compared to 24-2 VFs (-0.19 dB/year; IQR: -0.41, -0.03). Comparing the rates of MD change in eyes with different severities of VF loss (early [MD better than -6 dB], moderate [-6 dB to -12 dB], advanced [-12 to -20 dB] and severe [MD worse than -20 dB]) at baseline (based on the MD on 24-2 VF), median rate of MD change was comparable between 10-2 and 24-2 VFs in mild (-0.45 dB/year vs. -0.40 dB/year, P = 0.42) and moderate (-0.32 dB/year vs. -0.40 dB/year, P = 0.26) VF loss categories, while the same were significantly greater on 10-2 VFs in advanced (-0.28 dB/year vs. -0.21 dB/year, P = 0.04) and severe (-0.18 dB/year vs. -0.06 dB/year, P<0.001) VF loss categories.ConclusionsIn patients with VF defects both on 24-2 and 10-2 VFs, evaluating the rate of MD change on 10-2 VFs may help in better estimation of glaucoma progression, especially so in eyes with advanced glaucoma at baseline.     

The effectiveness of the stereomicroscopic evaluation of embryo quality in vitrified-warmed porcine blastocysts: an ultrastructural and cell death study

The objective of this study was to analyze the validity of the stereomicroscopic evaluation of vitrified-warmed (V-W) porcine blastocysts. Unhatched blastocysts were obtained from Large-white gilts (n=10). Blastocysts (n=156) were vitrified using the Open Pulled Straw technology. After warming, V-W blastocysts were cultured for 24h (V24). Then, their developmental progression was morphologically assessed by stereomicroscopy and classified as: V24 viable re-expanded blastocysts; V24 viable hatched blastocysts or V24 degenerated. Blastocysts which re-expanded or hatched after warming were considered viable. Some fresh blastocysts were not vitrified and were evaluated after 24h in culture (F24). By stereomicroscopic analysis all the fresh blastocysts were considered viable. Some F24, V24 re-expanded viable, V24 hatched viable and V24 degenerated blastocysts were processed for transmission electron microscopy (n=13, 19, 9 and 9, respectively) or assessed by TUNEL for cell-death evaluation (n=16, 21, 11 and 21, respectively). All V24 hatched blastocysts showed similar ultrastructure to fresh blastocysts. However, some V24 re-expanded blastocysts considered viable (6/19) revealed ultrastructural alterations. Degenerated V24 blastocysts showed ultrastructural disintegration. Hatched V24 blastocysts did not differ (p>0.05) from F24 hatched blastocysts with regard to the ratio of dead cells (2.8+/-0.5% versus 1.9+/-0.3%, respectively). However, V24 expanded blastocysts had higher (p<0.01) cell death levels (4.3+/-3.4%) than those observed in the F24 expanded blastocysts (1.1+/-0.3%). The degenerated blastocysts showed the highest cell-death index (19.4+/-6.3%). In summary, V-W blastocyst hatching during in vitro culture appears to coincide with good ultrastructure and low cell-death index, suggesting that the hatching rate assessed by stereomicroscopy is more appropriate than embryo re-expansion for an evaluation of V-W blastocyst quality.     

Evidence for separate intermediates in the biosynthesis of 24α- and 24β-alkylsterols in tracheophytes

When mevalonate-[2-¹⁴C] was incubated with seeds of Pinus pinea, 23% of the label in sterols was found in trans-24-ethylidenecholesterol, 12% in a mixture of 24α- and 24β-methylcholesterol, and 65% in 24α-ethylcholesterol. However, when the radioactive substrate was lanosterol-[24-³H], label appeared only in the 24-ethylidene- (85%) and the epimeric 24-methylsterols (15%). From the ratios of labels in the ethylidene- and methyl-sterols it was possible to show that the tritium in the 24-C₁ -mixture was incorporated only into the 24β-methyl epimer. The labelling patterns are consistent with a pathway to 24β-alkylsterols via Δ²⁵⁽²⁷⁾-sterols bypassing 24-ethylidenesterols and to 24α-alkylsterols via Δ²⁴⁽²⁸⁾-sterols which are isomerized to Δ²⁴⁽²⁵⁾-sterols prior to reduction.     

Bile acids. LXVIII. Allylic and benzylic photo-chemical oxidation of steroids

To provide 7-oxocholesterol derivatives in yields superior to those obtained by chemical oxidation, the preparation of steroidal allylic or benzylic ketones was studied. Air-induced oxidation was investigated with a highly selective low energy UV lamp in the presence of mercuric bromide. With this procedure cholesteryl acetate, 5-cholestene-3β, 27-diol diacetate, 24(R)-24-methyl-5-cholesten-3β-yl acetate, 24(R)-24-ethyl -5-cholesten-3β-yl acetate and 24(R)-24-ethyl-(22E)-cholesta-5, 22-dien -3β-yl acetate were oxidized to the allylic keto-derivative in good yields; estradiol-17β diacetate was similarly converted to the 6-oxo-product in improved yield. This method can be very useful in the synthesis of 7-oxocholesteryl acetate and its analogs and 6-oxoestratrienes.     

Intrathymic and intrasplenic oxidative stress mediates thymocyte and splenocyte damage in acutely exercised mice.

Reactive oxygen species may contribute to apoptosis in lymphoid tissues observed after exercise. Thymic and splenic tissues excised from control mice (C) or mice immediately after (t0) or 24 h after (t24) a run to exhaustion (RTE) were assayed for biochemical indexes of oxidative stress [thymic and splenic membrane lipid peroxides, superoxide dismutase, catalase, plasma uric acid (UA), and ascorbic acid (AA)]. There were significant increases in membrane lipid peroxides in thymus (P < 0.001) and spleen (P < 0.001) in acutely exercised mice relative to controls (thymus: C = 2.74 +/- 0.80 microM; t0 = 7.45 +/- 0.48 microM; t24 = 9.44 +/-1.41 microM; spleen: C = 0.48 +/- 0.22 microM; t0 = 1.78 +/- 0.28 microM; t24 = 2. 81 +/- 0.34 microM). The thymic and splenic tissue antioxidant enzymes concentrations of superoxide dismutase and catalase were significantly lower in samples collected at t0 relative to C and t24 mice (P < 0.001). Plasma UA and AA levels were used to assess the impact of the RTE on the peripheral antioxidant pool. There was no significant change in UA levels and a significant reduction in plasma AA concentrations (P < 0.001); the reduction in plasma AA occurred at t24 (6.53 +/- 1.64 microM) relative to t0 (13.11 +/- 0. 71 microM) and C (13.26 +/- 1.2 microM). These results suggest that oxidative damage occurs in lymphoid tissues after RTE exercise and that such damage may contribute to lymphocyte damage observed after acute exercise.     

The interaction of the steroidal antagonist faslodex and methotrexate.

Faslodex (FAS, ICI 182, 780), a novel steroidal estrogen antagonist decreased high-dose methotrexate (MTX) cytotoxicity in MCF-7 breast cancer cells. When FAS is given at least 24 hr prior to MTX, the resultant interaction is antagonistic. However, when breast cancer cells are exposed to FAS 24 hr after MTX, the interaction between FAS and MTX is not antagonistic. The proliferation of cells exposed to 0.1 microM FAS and 10 microM MTX alone or in combination with FAS 24 hr prior to MTX was in the following order: FAS>FAS 24 hr prior to MTX>MTX. MTX administration 24 hr prior to FAS had the following inhibitory effects on the growth of cells: MTX 24 hr prior to FAS >MTX>FAS 24 hr prior to MTX>FAS>control (no drug exposure). To determine if the antagonistic interaction between FAS and MTX was a function of sequence and time, cells were exposed to FAS 24 hr and 36 hr prior to MTX exposure. The percentages of control rates were 42.70 +/- 4.60% and 57.89 +/- 0.55%, respectively, from a 24 hr and 36 hr exposure of FAS prior to MTX. The growth rates after 24 and 36 hr exposures to MTX alone were 30.30 +/- 0.61% and 33.11 +/- 2.57% of control rates, respectively. These studies suggest that: a) the interactions between FAS and MTX are sequence-dependent; b) FAS antagonizes the effect of MTX when FAS administration precedes MTX, and c) FAS antagonism to MTX is a function of time.     

Structural and functional organization of ACTH: synthesis and properties of analogs of ACTH-(11-24)-tetradeca- and ACTH-(1-24)-tetracosapeptides containing hexa-amino acids instead of a natural sequence of ACTH 19-24 amino acids

To assess the role of amino acid sequence ACTH 19-24 in the corticotropin structure and steroidogenic activity, the analogues of ACTH-(11-24)-tetradeca- and ACTH-(1-24)-tetracosapeptides containing hexaglycine, hexaphenylalanine, hexaglutamic acid or hexalysine instead of the natural 19-24 sequence have been synthesized by conventional methods. All these compounds in water have the CD curves characteristic of random coil, CD spectra of analogue ACTH-(1-24)-tetracosapeptide and hexalysine-containing analogue ACTH-(11-24)-tetradecapeptide in trifluoroethanol indicate the presence of alpha-helices. The latter compound manifested higher steroidogenic activity than ACTH-(11-24)-tetradecapeptide. All the other analogues were either less active than ACTH-(1-24)-tetracosapeptide or inactive over the concentration range 10(-5)-10(2) mg/ml, thereby testifying to functional importance of the 19-24 sequence for manifesting full steroidogenic activity.     

Dissociation between metabolic and vascular insulin resistance in aging

Physiological actions of insulin via activation of the phosphatidylinositol 3-kinase/Akt pathway in the endothelium serve to couple regulation of hemodynamic and metabolic homeostasis. Insulin resistance, endothelial dysfunction, and hypertension increase in prevalence with aging. We investigated the metabolic and endothelial actions of insulin in 24- vs. 3-mo Sprague-Dawley rats. With the use of the hyperinsulinemic euglycemic clamp, the rate of glucose infusion necessary to maintain equivalent plasma glucose (5.5 mmol/l) was similar in 24- vs. 3-mo rats, as was fasting glucose (5.2 +/- 0.33 vs. 4.4 +/- 0.37 mmol/l; mean +/- SE) and insulin (0.862 +/- 0.193 vs. 1.307 +/- 0.230 mg/l). Systolic blood pressure was higher in 24-mo rats (133 +/- 5 vs. 110 +/- 4 mmHg; P = 0.005). Endothelial nitric oxide (NO)-dependent relaxation to insulin was impaired in aortas of 24- vs. 3-mo rats (maximal response 8.9 +/- 4.3 vs. 34.9 +/- 3.9%; P = 0.002); N(G)-nitro-l-arginine methyl ester abolished insulin-mediated relaxation in 3- but not 24-mo rats. Endothelium NO-dependent (acetylcholine) and -independent (sodium nitroprusside) relaxation, as well as NADPH oxidase activity, were similar in 3- and 24-mo rats. Insulin increased aortic serine phosphorylation of Akt in 3-mo rats by 120% over 24-mo rats (P < 0.05) and serine phosphorylation of endothelial NO synthase (eNOS) in 3-mo rats by 380% over 24-mo rats (P < 0.05). Aortic expression of phosphorylated c-Jun NH(2)-terminal kinase-1 and serine phosphorylated insulin receptor substrate-1, known mediators of metabolic insulin resistance, was similar in 3- and 24-mo rats. Expression of caveolin-1, a regulator of eNOS activity and insulin signaling, was 55% lower in 24- than 3-mo rats (P = 0.002). In summary, impaired vasorelaxation to insulin in aging was independent of metabolic insulin sensitivity and associated with impaired insulin-mediated activation of the Akt/eNOS pathway, but intact activation of the acetylcholine-mediated Ca(2+)-calmodulin/eNOS pathway. Vascular insulin resistance in aging may add to the increased susceptibility of this population to vascular injury induced by traditional cardiovascular risk factors.     

Urinary 18,19-dihydroxycorticosterone and 18-hydroxy-19-norcorticosterone excretion in patients with primary and secondary aldosteronism.

18,19-Dihydroxycorticosterone (18,19(OH)2-B) and 18-hydroxy-19-norcorticosterone (18-OH-19-nor-B) measurements were carried out on the urine of patients with primary aldosteronism (PA), essential hypertension (EHT), and liver cirrhosis with (LC, SA (+)) and without (LC, SA (-)) aldosteronism. The separation of these steroids was performed by extraction and high-performance liquid chromatography followed by radioimmunoassay (RIA) with specific antibodies prepared in our laboratory. 18,19(OH)2-B excretion was elevated in patients with PA (24 +/- 5.9 [+/- SE] micrograms/24 hr; n = 15) and LC, SA (+) (83 +/- 9.4 micrograms/24 hr; n = 8). Values in LC, SA (-) (3.1 +/- 1.2 micrograms/24 hr; n = 8) and in EHT (3.7 +/- 0.4 micrograms/24 hr; n = 42) were found to be similar to those in normal subjects (5.5 +/- 0.9 micrograms/24 hr; n = 30). The values of urinary 18-OH-19-nor-B in PA and LC, SA (+) were higher than in LC, SA (-) EHT and normal subjects (P less than 0.05). Values in the latter three groups, as compared with each other, did not show significant alterations. Nothing is known about the biologic relevance of 18,19(OH)2-B and very little about that of 18-OH-19-nor-B, but the latter steroid seems to potentiate experimental renal hypertension. One can speculate about possible roles of both steroids as precursors of other steroids, e.g., the biologically potent mineralocorticoid 19-noraldosterone. The data obtained suggest that it is not relevant to measure the urinary levels of either steroid in these clinical syndromes.     

The Effectiveness of Acupuncture in Prevention and Treatment of Postoperative Nausea and Vomiting - A Systematic Review and Meta-Analysis

Background

Acupuncture therapy for preventive and treatment of postoperative nausea and vomiting(PONV), a condition which commonly present after anaesthesia and surgery is a subject of growing interest.

Objective

This paper included a systematic review and meta-analysis on the effect of different type of acupuncture and acupoint selection in PONV prevention and treatment.

Methods

Randomised controlled trials(RCTs) comparing acupuncture with non-acupuncture treatment were identified from databases PubMed, Cochrane, EBSCO, Ovid, CNKI and Wanfangdata. Meta-analysis on eligible studies was performed using fixed-effects model with RevMan 5.2. Results were expressed as RR for dichotomous data, with 95%CI.

Results

Thirty RCTs, 1276 patients (intervention) and 1258 patients (control) were identified. Meta-analysis showed that PC6 acupuncture significantly reduced the number of cases of early vomiting (postoperative 0-6h) (RR=0.36, 95%CI 0.19,0.71; P=0.003) and nausea (postoperative 0-24h) (RR=0.25, 95%CI 0.10,0.61; P=0.002), but not early nausea (postoperative 0-6h) (RR=0.64, 95%CI 0.34,1.19; P=0.150) and vomiting (postoperative 0-24h) (RR=0.82, 95%CI 0.48,1.38; P=0.450). PC6 acupressure significantly reduced the number of cases of nausea (RR=0.71, 95%CI 0.57,0.87; P=0.001) and vomiting (RR=0.62, 95%CI 0.49,0.80; P=0.000) at postoperative 0-24h. PC6 electro-acupoint stimulation significantly reduced the number of cases of nausea (RR=0.49, 95%CI 0.38,0.63; P<0.000) and vomiting (RR=0.50, 95%CI 0.36,0.70; P<0.000) at postoperative 0-24h. Stimulation of PC6 with other acupoint(s) significantly reduced the number of cases of nausea and vomiting (RR=0.29, 95%CI 0.17,0.49; P<0.000) at postoperative 0-24h. Stimulation of other acupoint(s)(non PC6) also significantly reduced the number of cases of nausea and vomiting (RR=0.63, 95%CI 0.49,0.81; P=0.000) at postoperative 0-24h. However, the quality of study was generally low in studies of PC6 combined with other acupoint(s) and other acupoint(s). Details of blinding were not reported in most reports.

Conclusions

Besides PC6, PC6 combined with other acupoint(s) and other alternative acupoint(s) might be beneficial in prevention and treatment of PONV, the evidence justifies future high-quality studies.     

Effects of proopiomelanocortin-derived peptides, methionine-enkephalin and forskolin on the maturation of ovine fetal adrenal cells in culture

The present study examined the effects of peptides derived from the non-ACTH part of proopiomelanocortin (POMC), of met-enkephalin and of forskolin, alone or in combination with ACTH-(1-24), on the development of the ability of ovine fetal adrenal cells to produce both cAMP and corticosteroids in culture. N-POMC-(1-61) amide, gamma 2-melanocyte-stimulating hormone (MSH) and gamma 3-MSH behaved similarly in our system: 1) they increased slightly corticosterone (B) and cortisol (F) production without modification of cAMP output when added alone to the incubation medium, but this effect was observed only after 3 days in culture; 2) they potentiated the steroidogenic response to 10(-11) M ACTH-(1-24) but again only from Day 3 onwards; and 3) a 5-day treatment with the peptides induced fetal adrenal cell maturation resulting in the same enhancement of the B + F production stimulated by 10(-8) M ACTH-(1-24) without modification of the response in both cAMP and pregnenolone (P5). N-POMC-(1-80) and beta-lipotropic hormone (LPH) shared several common features in that, 1) the stimulation of B + F production by each of them alone was always significant and higher than that obtained with the other POMC-derived peptides [except ACTH-(1-24]; 2) they did not potentiate the steroidogenic action of 10(-11) M ACTH-(1-24); and 3) when cells were cultured in their presence for 5 days it resulted in an enhancement of the response to ACTH-(1-24), not only in B + F production but also in cAMP and P5 outputs. No effect of met-enkephalin was observed. The development of cAMP and B + F responses to ACTH-(1-24) provoked by forskolin was very close to that induced by the hormone itself, but forskolin, as opposed to ACTH-(1-24), was unable to induce a desensitization of the cAMP response. These data show that N-POMC-derived peptides can potentiate the acute steroidogenic activity of ACTH-(1-24) on ovine fetal adrenal cells after several days in culture.     

Adrenal adenylate cyclase and steroidogenic activities of 63 day old ovine fetuses: in vitro effects of ACTH1-24 and forskolin

This study examines the activity of the adenylate cyclase system and that of some enzymes of the steroidogenic pathway of adrenal cells from 62-63 day old ovine fetuses. Synthetic corticotropin (ACTH1-24), cholera toxin and forskolin stimulated both cAMP and corticoid productions by freshly isolated adrenal cells. The cAMP response to ACTH1-24 was lower than that to forskolin. However, forskolin-induced steroidogenesis was significantly lower than the ACTH1-24-induced steroid output. Freshly isolated cells metabolized quickly [14C]-labeled pregnenolone mainly through the 17-deoxy pathway. The amounts of cortisol and of corticosterone formed, in the presence of exogenous pregnenolone, were roughly 15-fold higher than under maximal stimulation by ACTH1-24. When the cells were cultured for 6 days in the absence or presence of ACTH1-24 (10(-8) M) or forskolin (10(-5) M), a small development of the cAMP response to these factors was observed in the course of the experiment. However, the mechanism of this development appeared different, according to the conditions of culture. The amounts of corticosterone secreted on day 6 by ACTH1-24- or forskolin-treated cells were 2- to 4-fold higher than on day 1, whereas cortisol outputs were much lower on day 6 than on day 1. The response to ACTH1-24 of cells maintained in ACTH-free media decreased dramatically during the culture in terms of both cortisol and of corticosterone. On day 6 of the experiment, the metabolism of [14C]pregnenolone was lower than on day 1 under all 3 conditions of culture. Only the 3 beta-hydroxysteroid dehydrogenase/isomerase activity could be maintained by continuous treatment with forskolin. However, both ACTH1-24 and forskolin enhanced the production of pregnenolone from an endogenous substrate. In conclusion, these results present evidence that: 1) the adenylate cyclase system is not a bottleneck in the steroidogenic response to ACTH1-24 of freshly isolated adrenal cells from 62-63 day old ovine fetuses; 2) the main rate-limiting step for steroidogenesis by these cells is the availability of pregnenolone; 3) neither ACTH1-24 nor forskolin is able to maintain the activity of most enzymes involved in the metabolization of pregnenolone by cultured cells while increasing pregnenolone availability; 4) some inhibiting factors are involved in the loss of adrenal cells responsiveness to ACTH between days 50 and 100 of gestation, and they probably act mainly on the adenylate cyclase system.