Metabolism and conjugation of [4-14C]progesterone by bovine liver and adipose tissues, in vitro

The ability of bovine liver and fat to metabolize progesterone and also to form glucuronide conjugates with these progestins $\text{in vitro}$ was investigated. Tissue supernatants were incubated with [4-¹⁴C] progesterone, UDP-glucuronic acid, and a NADPH generating system for 5 hr, at 37°C. Steroids were identified by thin-layer chromatography, high performance liquid chromatography, and recrystallization to a constant specific activity. The total original radioactivity which could not be removed by exhaustive ether extraction (presumptive conjugates) was 44.7 ± 14.2% in liver, 5.0 ± 3.6% in subcutaneous fat, and 3.7 ± 2.2% in kidney fat samples. Progestins identified in liver samples include 5β-pregnane-3α, 20α-diol (free and conjugate), 5β-pregnane-3α, 20β-diol (free and conjugate), 3α-hydroxy-5sB-pregnan-20-one (free and conjugate), 3β-hydroxy-5β-pregnan-20-one (free), 5β-pregnane-3, 20-dione (free), and progesterone (conjugate). Progestins identified in both the free and conjugate fractions of subcutaneous fat and kidney fat samples include progesterone, 3α-hydroxy-5β-pregnan-20-one, 20β-hydroxy-4-pregnen-3-one, and 20α-hydroxy-4-pregnen-3-one. Differences due to sex of bovine used were noted. These results confirm the ability of bovine liver to readily metabolize progesterone and form glucuronide conjugates of these compounds and suggest that adipose tissues take an active role in these actions in cattle.     

Metabolism of 5β-pregnane-3,20-dione and 3β-hydroxy-5β-pregnan-20-one by Digitalis suspension cultures

Digitalis purpurea normal callus suspension culture is capable of metabolizing 5β-pregnane-3,20-dione (1) to 3β-hydroxy-5β-pregnan-20-one (2), 3α-hydroxy-5β-pregnan-20-one (3), 3β-hydroxy-5β-pregnan-20-one glucoside (7) and 3α-hydroxy-5β-pregnan-20-one glucoside (8). Digitalis purpurea habituated callus suspension culture is also capable of metabolizing 1 to 2, 3, 5β-pregnane-3β,20β-diol (5), (7), (8), 5β-pregnane-3β,20α-diol monoglucoside (9) and 5β-pregnane-3α,20α-diol monoglucoside (11). Furthermore, it was observed that 3β-hydroxy-5β-pregnan-20-one (2) is converted to 7, 9 and 11 by both suspension cultures. At the same time, 1, 3, 5 and 8 were detected in normal callus, while 5β-pregnane-3β,20α-diol (4) and 5β-pregnane-3β,20β-diol monoglucoside (10) were present in the habituated callus culture.     

Triterpenes from Ferula linkii

Two new natural triterpenes, 3β-acetoxyolean-9,12-diene and 3β-acetoxy-6β-hydroxyolean-9,12-diene, were isolated from Ferula linkii.     

糖基转移酶β3GnT8／β3GalT7在多种肿瘤细胞中的表达

目的：探讨一种新的糖基转移酶β3GnT8／β3GalT7在多种肿瘤细胞中的mRNA表达情况。方法：运用半定量RT-PCR方法研究人β3GnT8／β3GalT7基因在11种恶性肿瘤细胞中的表达谱。结果：β3GnT8／β3GalT7基因在多种肿瘤细胞株中都有表达,在A549细胞中的表达最高,在SGC7901细胞中中度表达,在白血病细胞中的表达较低。结论：β3GnT8／β3GalT7基因在11种肿瘤细胞中的表达有显著差异。     

Microbiological oxidation of sterols by Coriolus hirstus

Fermentation of cholesterol with a culture of Coriolus hirstus yielded a mixture containing 7-oxo-cholesterol and hydroxylated-cholesterol derivatives. Preparation of a possible precursor of antheridiol, 7-oxofucosterol, by this fungus was also examined.     

Biosynthesis of the tigloyl esters in Datura: The role of 2-methylbutyric acid

Datura innoxia plants were wick fed with (±)-2-methylbutyric acid-[1-¹⁴C] and harvested after 7 days. The root alkaloids 3α,6β-ditigloyloxytropane and 3α,6β-ditigloyloxytropan-7β-ol were isolated and degraded. In each case the radioactivity was located in the ester carbonyl group indicating that this acid is an intermediate in the biosynthesis of tiglic acid from l-isoleucine. On the other hand, (±)-2-hydroxy-2-methylbutyric acid-[1-¹⁴C], which was fed to hydroponic cultures of Datura innoxia alongside isoleucine[U-¹⁴C] positive control plants, is not an intermediate.     

The conversion of testosterone to 7α-hydroxy-testosterone by incubated rat testes

Incubations of testes of adult rats with testosterone yield rather important amounts of a very polar metabolite which is identified as 7α-hydroxytestosterone. The identification of the metabolite is based on chromatography, spectrophotometry, fluorimetry, counter current distribution and NMR spectrometry.     

The in vivo metabolism of 7 beta, 17-dimethyltestosterone-6,7-3H.

7 beta, 17-Dimethyltestosterone (17 beta-hydroxy-7 beta, 17-dimethyl-4-androsten-3-one) (I) was given to three subjects in oral doses of 400 mg per day for ten days. The initial dose contained the steroid tritiated in the 6 and 7 positions. Plasma levels and urinary excretion patterns were followed in all three subjects. Isolations were done on the urine, plasma, and stools of one patient. From the urine 7 beta, 17-dimethyl- 5 alpha-androstane-3 beta,17 beta-diol (VI) was isolated from the nonhydrolyzed fractions. Unchanged (I), 7 beta,17-dimethyl-5 beta-androstane-3 alpha,17 beta-diol (III) and 7 beta, 17-dimethyl-5 beta-androstane-3 beta,17 beta-diol (IV) were isolated from the nonhydrolyzed and enzyme-hydrolyzed fractions. 7 beta,17-dimethyl-5 alpha-androstane-3 alpha,17 beta-diol (V) was isolated from the enzymatic fractions. From the stools were isolated unchanged (I), (III), (IV), (V), and (VI). Unchanged (I) and its 5 alpha-dihydro derivative (17 beta-hydroxy-7 beta,17-dimethyl-5 alpha-androstan-3-one) (II) were identified in the plasma. The total recovery of radioactivity in the one patient on whom the isolations were done was 57%; 40% from the urine and 17% from the stools.     

Proteasomal degradation of Atoh1 by aberrant Wnt signaling maintains the undifferentiated state of colon cancer

Atoh1 plays a crucial role in intestinal cell differentiation. We have demonstrated that its human homolog Hath1 protein is targeted by the Wnt-GSK3 axis, resulting in the proteasomal degradation in human colon cancer. However, the contribution of Hath1 degradation to the undifferentiated state of colon cancer remains unknown. In this study, we demonstrated that both constitutive expression of mutant Hath1 and stabilization of Hath1 protein by a GSK3 inhibitor in colon cancer cells increased the expression of MUC2 known as a representative function of differentiated goblet cells. This means that Hath1 protein degradation may be required for maintaining the undifferentiated state of colon cancers, and that GSK3 inhibitors have potential for use in cancer therapy.     

Configuration at C-24 of sterols from the liverwort Palavicinnia lyellii

The 4-desmethylsterol fraction of the liverwort Palavicinnia lyellii is composed of 36% 24β-methylcholest-5-en-3β-ol (dihydrobrassicasterol), 16% 24α-methylcholest-5-en-3β-ol (campesterol), 33% 24α-ethylcholest-5-en-3β-ol (sitosterol) and 15% 24ξ-ethylcholesta-5,22-dien-3β-ol.     

IP3 Receptor-Dependent Cytoplasmic Ca2+ Signals Are Tightly Controlled by Cavβ3

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Biosynthesis of ditigloyl esters of DI- and tri-hydroxytropanes in Datura

3α-Tigloyloxytropane-[¹⁴CO] [N-¹⁴Me], ratio 1·6:1 and valtropine-[¹⁴CO] [N-¹⁴Me], ratio 1·75:1 were separately fed via cotton wicks to 4-month-old Datura innoxia plants. After 8 days the root alkaloids 3α-tigloyloxytropane, 3α,6β-ditigloyloxytropane and 3α,6β-ditigloyloxytropan-7β-ol were isolated and the distribution of radioactivity in the acid and alkamine moieties was determined by hydrolysis. The precursor ratios were not maintained in the isolated ditigloyl esters, a result which does not support our hypothesis that the ditigloyl esters are formed by the progressive hydroxylation of 3α-tigloyloxytropane.     

Two new triterpenoids from Rhodomyrtus tomentosa

Repetition of an investigation of the petrol extracts of Rhodomyrtus tomentosa has led to the isolation of two new triterpenoids, R₄ from the leaves and R₅ from the stems besides R₁, R₂, R₃ and the other known compounds already reported. R₁ and R₄ were proved to be 21α$\text{H}$-hop-22(29)en-3β,30-diol and 3β-hydroxy-21α$\text{H}$-hop-22(29)-en-30-al respectively, and R₂, R₃ and R₅ are 3β-acetoxy-11α,12α-epoxyoleanan-28,13β-olide, 3β-acetoxy-12α-hydroxyoleanan-28, 13β-olide and 3β-acetoxy-12-oxo-oleanan-28,13β- olide respectively. The ethanol extract of the leaves contained betulinic, ursolic and aliphitolic acids and that of the stems betulonic, betulinic and oleanolic acids.     

Betaig-h3 supports keratinocyte adhesion,migration, and proliferation through alpha3beta1 integrin

betaig-h3 is an extracellular matrix protein and its expression is highly induced by TGF-beta and it has also been suggested to play important roles in skin wound healing. In this paper, we demonstrate that betaig-h3 is present in the papillary layer of dermis and synthesized in the basal keratinocytes in vivo and its expression is induced by TGF-beta in normal human keratinocytes (NHEK) and HaCaT cells. betaig-h3 mediates not only adhesion and spreading of keratinocytes but also supports migration and proliferation. These activities are mediated through interacting with alpha3beta1 integrin. Previously identified two alpha3beta1 integrin-interacting motifs of betaig-h3, EPDIM, and NKDIL, are responsible for these activities. The results suggest that betaig-h3 may regulate keratinocyte functions in normal skin and potentially during wound-healing process.     

NMR Investigations of the interaction of water with lecithin in benzene solutions

NMR investigations of ¹H (chemical shifts, line widths) and of ³¹P (relaxation times, T₁) performed on the three-component system of lecithin-benzene-water show that there is an interaction of water with the phosphate group in two regions of different mobility and structure. A fast exchange of the water molecules takes place between both regions. The region of strong interaction involves about 2 and that of the weaker interaction about 5 water molecules per lecithin molecule. When the water concentration is increased a third region is formed which is assigned to the water molecules that are located beyond the two regions of interaction with the phosphate group, but within the micelle. This water has a different structure from that of the second region of interaction with the phosphate group and may also have a different mobility.Addition of water increases the motion of the head groups of the lecithin molecules. This is due to a loosening of the packing of lecithin molecules.     

Persistent enhancement of bile acid synthesis in guinea pigs following stimulation of cholesterol catabolism in neonatal life

Cholesterol catabolism to bile acids was stimulated in neonatal guinea pigs by feeding 1,11% cholestyramine (CT)-containing diet for 8 weeks. The animals were then switched to standard laboratory diet for an additional 4 weeks. At the end of the laboratory diet period: a) CT-pre-treated guinea pigs continued to excrete significantly higher (p<0.05) amounts of bile acids, b) the activity of hepatic 7α-hydroxylase was significantly elevated (p<0.01) in CT-pre-treated animals, and c) isolated hepatocytes from CT-pre-treated guinea pigs secreted significantly higher (p<0.05) amounts of bile acid when compared to controls during a 4-hour incubation. These data provide biochemical support for our contention that stimulation of cholesterol catabolism during neonatal life can have effects that persist into adult life.     

Simultaneous radioimmunoassay of testosterone,dihydrotestosterone, 5α-androstane-3α, 17β-diol and 5α-androstane-3β, 17β-diol in the plasma of adult male rats

A single thin layer chromatography and three antibodies were used for the specific radioimmunoassay of four androgens in pooled rat plasma (Sprague-Dawley adult males). The following values were found (pg/ml ± SD). Testosterone : 3, 138 ± 173; dihydrotestosterone : 374 ± 20; 5α-androstane-3α 17β-diol : 284 ± 24; 5α-androstane-3β, 17β-diol : 223 ± 11.     

Biosynthesis of the tigloyl esters of Datura: Cis-trans isomerism

Datura innoxia plants were wick fed with angelic acid-[1-¹⁴C] and l-isoleucine-[U-¹⁴C] to act as a positive control. After 7 days the root alkaloids 3α-tigloyloxytropane, 3α,6β-ditigloyloxytropane, and 3α,6β-ditigloyloxytropan-7β-ol were isolated and it was determined that angelic acid is not a precursor for the tigloyl moiety of these alkaloids. Tiglic acid-[1-¹⁴C] which was fed via the roots to hydroponic cultures of Datura innoxia, was incorporated to a considerable degree after 8 days.     

Codisterol and other Δ5-sterols in the seeds of Cucurbita maxima

A substantial amount (ca 18%) of the sterol found in the seeds of Cucurbita maxima had a Δ-bond and consisted of seven components. They were identified as 25(27)-dehydroporiferasterol, clerosterol, isofucosterol, stigmasterol, sitosterol, campesterol and codisterol. The C-24 configuration of each of the sterols was unequivocally established by a ¹H NMR spectral comparison with authentic standards. This is the first time codisterol has been found in a higher plant and also the first time the structures and configurations of the Δ⁵-sterols from a Cucurbitaceae species have been clearly characterized.