Metabolism of 3β-hydroxy-5α- and 3β-hydroxy-5β-pregnan-20-one by leaf homogenates

Leaf homogenates of Cheiranthus cheiri, Nerium oleander, Strophanthus kombé, Digitalis purpurea, and Corchorus capsularis were ex     

Synthesis of 3α,7α-dihydroxy-5β-androstan-17-one

A short and efficient method for the stereospecific synthesis of 3α,7α-dihydroxy-5β-androstan-17-one was accomplished from the readily available 4-androstene-3,17-dione. Key steps are the stereospecific and selective epoxidation of 4,6-androstadiene-3,17-dione, followed by hydrogenations with carefully selected reagents, solvents and reaction conditions.     

A direct radioiodination technique for the radioimmunoassay of 17α-ethynyl, 17β-hydroxy-4-estren-3-one

A new technique is described for the direct labelling of norethisterone with¹²⁵I for use in radioimmunoassay. This method allows the preparation of tracers possessing both high specific activity and unaltered immunological properties. The steroid is radioiodinated in the presence of H₂O₂ using acetic acid as the solvent, in a sealed vial heated at 100°C. The reaction mixture is then chromatographed on bidimensional t.l.c. and six major radioactive spots are separated; only one of these fractions possess immunoreactivity. When submitted to repeated t.l.c. it behaves as a single compound, possibly a monoiodinated derivative, substituted in Ring A.The new tracer was compared in RIA with both the tyrosine-iodinated and the tritiated tracers. The standard inhibition curve obtained with the new labelled ligand had the same slope as that obtained using the tritiated one; on the other hand the slope of the curve obtained with the tyrosine iodinated derivative was slightly higher than that of the directly iodinated one.The results obtained indicate that the possibility exists of radioiodinating steroids without losing their immunoreactivity.     

Metabolism of 17β-hydroxy-2-hydroxymethylene-5α-androstan-3-one in the rabbit

An acidic metabolite, 2α-carboxy-5α-androstane-3α, 16α, 17αtriol and two neutral metabolites, 2α-hydroxymethyl-5α-androstane-3α, 17α-diol, and 2α-hydroxymethyl-5α-androstane-3α, 16α, 17α-triol have been identified in the urine of rabbits orally dosed with 17β-hydroxy-2-hydroxymethylene-5α-androstan-3-one. 2α-Hydroxymethyl-5α-androstane-3α, 16α, 17α-triol was previously obtained from the urine of rabbits dosed with 17β-hydroxy-2α-methyl-5α-androstan-3-one. The acidic metabolite was the major urinary excretion product.     

Synthesis of 5α-Androstane-3α,16α,17β-triol from 3β-hydroxy-5-androsten-17-one

5α-Androstane-3α, 16α 17β-triol was synthesized from 3β-hy-droxy-5-androsten-17-one. The procedure Involved catalytic hydrogenation of 3β-hydroxy-5-androsten-17-one to 3β-hydroxy-5α-androstan-17-one. This was followed by conversion of the 3β-hydroxy group to 3α-benzoyloxy group by the Mitsunobu reaction. Further treatment with isopropenyl acetate yielded 5α-androsten-16-ene-3α, 17-diol 3-benzoate 17-acetate. This was then converted to 3α, 17-dihydroxy-5α-androstan-16-one 3-benzoate 17-acetate via the unstable epoxide intermediate after treatment with $\text{m}$-cloroperoxybenzoic acid. LiAlH₄ reduction of this compound formed 5α-androstane-3α, 16α, 17β-trlol. ¹H and ¹³C NMR of various steroids are presented to confirm the structure of this compound.     

Synthesis of a labelled putative precursor of ecdysone—II: [3H4]3β-hydroxy-5β-cholest-7en-6-one: Critical re-evaluation of its role in Locusta migratoria

We have synthesized a tritiated form of 2,14,22,25-tetradeoxyecdysone (5β-ketol) of high specific activity (115 Ci/mmol). We have examined the capacity of various tissues of Locusta migratoria to use this 5β-ketol, a putative precursor of ecdysone, in ecdysteroid biosynthesis. While larval prothoracic glands convert the radiotracer to labelled 14-deoxyecdysone they fail to hydroxylate the molecule to ecdysone itself. Other larval tissues, embryonic tissues or vitellogenic female ovaries are unable to convert the radiotracer to ecdysone, 20-hydroxyecdysone or 2-deoxyecdysone, the terminal products of biosynthesis in different developmental stages. Using subcellular preparations of prothoracic glands or follicle cells we have been unable to show a biological C-14 hydroxylation of 5β-ketol. It thus appears that the step of C-14 hydroxylation in the biosynthesis of ecdysteroids requires a substrate other than 5β-ketol.     

The microbial production of 3aα-H-4α- (3′-propionic acid)-5α-hydroxy-7aβ-methylhexahydro-indan-1-one-δ-lactone from cholesterol

Summary A mutant strain of Rhodococcus australis CSIR-236.457 which accumulates 3a-H-4-(3-propionic acid)-5-hydroxy-7a-methylhexahydro-indan-1-one--lactone from cholesterol, stigmasterol and -sitosterol was studied. The product is produced in a 60% molar yield in a dilute black strap molasses medium containing 6–12g/l cholesterol after a 72 hour fermentation period.     

Masson’s tumor of the kidney: a case report

Background

Intravascular papillary endothelial hyperplasia (known also as Masson’s tumor) is a benign vascular lesion that commonly occurs in the skin and is rarely found in solid organs, especially in the kidney. In what follows, we will look into the first case of an unexpectedly diagnosed Masson’s tumor of the kidney presenting as a suspicious renal cyst.

Case presentation

A 61-year-old Arab man presented with a left renal cyst, incidentally revealed by ultrasonography. The laboratory values were unremarkable. Computed tomography and magnetic resonance imaging demonstrated a 38 mm left renal midportion Bosniak IV cyst. Our patient underwent a radical nephrectomy. Histopathology revealed the diagnosis of intravascular papillary endothelial hyperplasia. There was no recurrence detected after 9 years of follow-up.

Conclusions

Renal intravascular papillary endothelial hyperplasia is a rare benign tumor which can mimic a suspicious renal mass on radiological findings. Thus, this entity should be considered more often in the thick of the diagnostic possibilities in order to avoid unnecessary nephrectomies.

     

Outcome of a multimodal therapy of a recurrent adenocarcinoma arising from Caesarean section scar endometriosis—A case report

Background

Endometriosis occurring in surgical scars is a well-described entity. Malignant transformation of endometriosis is a rare event, with most cases belonging to adenocarcinoma. The initial surgical treatment is a method of choice. Due to lack of therapeutic recommendations, adjuvant therapy and recurrence management are a great challenge for oncologists.

Aim

The aim of this paper was to present a long-term survival as the outcome of multimodal therapy in the patient with recurrent adenocarcinoma arising from Caesarean section scar endometriosis.

Case

We present the case of a woman with recurrent adenocarcinoma arising from Caesarean section scar endometriosis. The disease was first diagnosed in September 1997 at age 43. The patient underwent abdominal hysterectomy with tumour excision. Due to a local recurrence after 4 years, tumour excision with abdominal wall repair using a plastic mesh, regional lymphadenectomy, bilateral salpingo-ovariectomy and adjuvant radiotherapy for the pelvic region with local boost were performed; in addition hormontherapy with medroxyprogesterone was started. Because of a recurrent pelvic tumour, chemotherapy, further local palliative radiotherapy and brachytherapy were administered. Subsequently distant metastases in bilateral axillary lymph nodes were diagnosed and palliative radiotherapy was performed. The patient died of morbus neoplasmaticus generalisatus in September 2008. The follow-up period had been 132 months.

Conclusion

This paper is, to our knowledge, the only report in literature that presents a long-term survival as the outcome of multimodal therapy in the patient with this rare diagnosis. Further reports of new cases can help establish optimal treatment guidelines.     

Development of hepatic microsomal activity of 3-hydroxy-3-methylglutaryl-coenzyme a reductase and cholesterol 7α-hydroxylase in the young chick

• 1.1. The 3-hydroxy-3-methylglutaryl-CoA reductase activity increased from 1 to 4 weeks of age, but decreased from 4 to 8 weeks of age.
• 2.2. Cholesterol 7α-hydroxylase activity increased from 1 to 4 weeks, decreased from 4 to 6 weeks, and increased again from 6 to 8 weeks of age.
• 3.3. Serum total and free cholesterol concentrations decreased from 1 to 6 weeks of age, but increased from 6 to 8 weeks of age.

     

Choreoathetosis – an unusual adverse effect of dihydroartemisinin-piperaquine: a case report

Background

Dihydroartemisinin-piperaquine is a combination of dihydroartemisinin and piperaquine which is highly effective in the treatment of uncomplicated falciparum malaria. Its adverse effects are generally tolerable and temporary. Choreoathetosis, an involuntary movement disorder characterized by continuous irregular twisting of the body, is not a documented adverse effect of this medication.

Case presentation

A 41-year-old Cameroonian man of black African ethnicity was brought to our primary care hospital because over the previous 6 hours he had been experiencing involuntary twisting movements of his body and he no longer had control of his limbs. Earlier that day, he had been prescribed an appropriate dose of dihydroartemisinin-piperaquine in our hospital. The abnormal movements started approximately 3 hours after ingesting the first dose of the drug. The review of systems and his past history were unremarkable. On clinical examination, he was conscious and oriented but was unsteady and displayed continuous generalized irregular twisting movements combined with abrupt low amplitude flinging of his limbs. Dihydroartemisinin-piperaquine-induced generalized choreoathetosis was diagnosed. He was sedated with diazepam and dihydroartemisinin-piperaquine was discontinued. The antimalarial drug was substituted with artemether-lumefantrine combination. The clinical progress was good and he was discharged home after 72 hours. No further abnormalities were noted during 7 months of follow-up.

Conclusion

Although dihydroartemisinin-piperaquine is increasingly popular as a well-tolerated/efficacious antimalarial drug, clinicians must note the rare possibility of choreoathetosis as an adverse effect of this medication and educate patients accordingly.

     

7α-hydroxy-3-oxo-4-cholestenoic acid in cerebrospinal fluid reflects the integrity of the blood-brain barrier

There is a continuous flux of the oxysterol 27-hydroxycholesterol (27-OHC) from the circulation across the blood-brain barrier (BBB) into the brain. The major metabolite of 27-OHC in the brain is 7α-hydroxy-3-oxo-4-cholestenoic acid (7-HOCA). We confirm a recent report describing the presence of this metabolite in cerebrospinal fluid (CSF) at a relatively high concentration. A simple and accurate method was developed for assay of 7-HOCA in CSF based on isotope dilution-mass spectrometry and use of ²H₄-labeled internal standard. The concentration of this metabolite was found to be markedly increased in CSF from patients with a dysfunctional BBB. There was a high correlation between the levels of 7-HOCA in CSF and the CSF/serum albumin ratio. The concentration of 7-HOCA in CSF was not significantly affected by neurodegeneration. Our findings suggest that 7-HOCA could be used as a diagnostic marker for conditions with a dysfunctional BBB.     

Purification and properties of a nad: 3α-hydroxy-5α-pregnan-20-one-oxidoreductase from rat liver microsomes

From rat liver microsorties a NAD: 3α-hydroxy-5α-pregnan-20-one oxidoreductase was isolated and purified up to a specific activity of 73 nmol/min.mg by affinity chromatography and DEAE-cellulose chromatography. Various Km-values have been determined. The enzyme exhibits highest affinity for 5α-pregnane-3,20-dione and NADH. The 3-oxo group of 5α-dihydrocortisone (17, 21-dihydroxy-5α-pregnane-3,11,20-trione) was not reduced by the purified enzyme preparation and NADH and no dehydrogenation with NAD was observed of 3α, 11β, 17, 21-tetrahydroxy-5α-pregnan-20-one. The optimal pH for the hydrogenation of the 3-oxo group was at pH 5.3 and for the dehydrogenation at pH 8.9. Disc gel electrophoresis in presence of 0.1% sodium dodecylsulfate yielded a homogeneous preparation.     

4-cholesten-3-one suppresses lung adenocarcinoma metastasis by regulating translocation of HMGB1, HIF1α and Caveolin-1

Metastasis is a great challenge in lung adenocarcinoma (ADC) therapy. Cholesterol has been implicated in ADC metastasis. 4-cholesten-3-one, as cholesterol metabolite and analog, can substitute membrane cholesterol and increase membrane fluidity. In this study, we explored the possibility that 4-cholesten-3-one inhibited ADC metastasis. Low-dose 4-cholesten-3-one significantly restrained ADC cells migration and invasion with little effects on cells viabilities. Further investigation showed that 4-cholesten-3-one promoted ROS generation, which transiently activated AMPKα1, increased HIF1α expression, reduced Bcl-2 expression and caused autophagy. AMPKα1 knockdown partly suppressed 4-cholesten-3-one-induced autophagy but, neither prevented 4-cholesten-3-one-induced upregulation of HIF1α or downregulation of Bcl-2. 4-cholesten-3-one-induced autophagy facilitated the release of HMGB1 from nuclei to cytoplasm, blocking nuclear translocation of HIF1α and activation of MMP2 and MMP9. Also, 4-cholesten-3-one induced time-dependent phosphorylation of caveolin-1, Akt and NF-κB. With increasing treatment time, 4-cholesten-3-one accelerated caveolin-1 internalization, but reduced the phosphorylation of Akt and NF-κB, and inhibited the expression of snail and twist. These data suggested that 4-cholesten-3-one could be a potential candidate for anti-metastasis of lung adenocarcinoma.Lung cancer is the leading cause of cancer-related death globally, with an estimated incidence of 1.3 million new cases every year.¹ Lung adenocarcinoma (ADC) is the main common subtype of lung cancer. The high mortality of ADC is mainly attributed to early metastasis.² Because metastasis is a complex and multistep process, the molecular mechanisms of ADC metastasis remain largely unknown.Malignant cells migration is an early event of metastasis, followed by intravasation, survival in the circulation, extravasation and colonization at distant target organs.³ Recent studies have found the connection between cholesterol metabolism and metastases.^{4, 5, 6} Diet-induced hypercholesterolemia accelerates prostate cancer metastases to lymph node, lung and bones.⁷ Inhibition of cholesterol biosynthesis hampers the metastases of colon carcinoma and pancreatic ADC.^{8, 9} The cholesterol metabolite 27-hydroxycholesterol promotes breast cancer metastasis by activating liver X receptor.¹⁰ Cholesterol as an essential component of lipid rafts impacts diverse signaling molecules that mediate multiple biological functions, such as cell survival and death.¹¹ A series of evidences have confirmed that the depletion of membrane cholesterol disrupts lipid rafts, resulting in cell apoptosis.^{12, 13, 14} Elevated cholesterol level has been found in various tumors, including prostate, lung, acute myeloid leukemia and breast cancer,^{15, 16, 17, 18} especially in chemoresistant tumors.^{19, 20} Cholesterol accumulation in solid tumors promotes the proliferation, differentiation and migration of tumor cells by mediating cellular surface molecules, such as caveolin-1 translocation.²¹ Depletion of membrane cholesterol suppresses the phosphorylation of Akt and ERK.^{22, 23} Furthermore, membrane cholesterol depletion also restrains the expression of BCL-2 family members.²⁴ Thus, dysregulated cholesterol metabolism is likely to be implicated in tumor metastases through related signaling pathway.Our previous results suggest that cholesterol oxidation by cholesterol oxidase from Bordetella species (COD-B) promotes the irreversible apoptosis of ADC cells.²⁵ COD-B as a microbial flavoprotein can oxidize cholesterol to 4-cholesten-3-one. In this study, we further investigated whether 4-cholesten-3-one influenced ADC metastasis. We evidenced that low-dose 4-cholesten-3-one inhibited ADC migration in vitro and metastasis in vivo by inducing the translocations of HMGB1, HIF1α and caveolin-1. Our data demonstrated that translocations of HMGB1 and HIF1α had key roles in ADC metastasis.     

Biocatalytic synthesis of 4-pregnen-20,21-diol-3-one,a selective inhibitor of human 5α-reductase type II

Biocatalysis, the conversion of substrates into valuable products by the use of enzymes, has some striking advantages in comparison to standard organic chemistry for drug synthesis. By biocatalysis, substrates that contain several identical reactive groups at different positions can be converted with high regio-selectivity and enantio-selectivity. In this study, an E. coli isolate (E132) was identified which was able to convert the steroid desoxycorticosterone into the product 4-pregnen-20,21-diol-3-one in real terms. The product was purified from the cell culture supernatant by HPLC and its structure was demonstrated by mass spectrometry and NMR spectroscopy. It was tested on inhibition of human 5α-reductases type I and type II. At a concentration of 10 μM, inhibition was 49.0% for type I and 81.8% for type II, whereas there was no inhibition of human aromatase (CYP19) at 20 μM and human 17α-hydroxylase-C_17,20-lyase (CYP17) at 2.5 μM detectable. The IC₅₀ value of 4-pregnen-20,21-diol-3-one for human 5α-reductase type II was determined to be 1.56 μM.     

Synthesis of 3β-hydroxy-androsta-5,7-dien-17-one from 3β-hydroxyandrost-5-en-17-one via microbial 7α-hydroxylation

The synthesis of 3β-hydroxy-androsta-5,7-dien-17-one from 3β-hydroxy-androst-5-en-17-one (dehydroepiandrosterone, DHEA) via microbial 7α-hydroxylation has been accomplished. At the first stage, 3β,7α-dihydroxy-androst-5-en-17-one was obtained in high yield (71.2%) using a strain of Gibberella zeae VKM F-2600, which was first applied for DHEA conversion. The further route included the substitution of 7α-hydroxyl group with chlorine followed by a dehydrochlorination stage, and required minimal purifications of the intermediate products. The steroids obtained at every step were characterized by TLC_,¹H NMR, MS, UV- and IR-spectrometry.The combination of microbial and chemical steps ensured 54.6% yield of the target 3β-hydroxy-androsta-5,7-dien-17-one from DHEA and can be applied for obtaining novel vitamin D derivatives.