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Steroid Metabolism

The biosynthesis of steroids originates with farnesyl pyrophosphate through reductive dimerization to squalene by squalene synthase and a subsequent enzymatic conversion of squalene to lanosterol. Enzymatic epoxidation of squalene by squalene epoxidase then yields (3S)-2,3-oxidosqualene. Subsequent catalysis by oxidosqualenelanosterol cyclase generates four rings, six carbon-carbon bonds, and seven chiral centers in one enzymatic reaction and results in a tetracyclic triterpene steroid frame.

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79849   (±)-Mevalonic acid 5-phosphate lithium salt hydrate 95% (TLC) Metabolite of the mevalonate pathway, which plays a key role in the biosynthesis of sterols, dolichol, heme and ubiquinone. Of interest for research in the disease areas oncology, autoimmune diseases, artherosclerosis and Alzheimer disease, as well as for inherited deficiencies of mevalonate kinase.
94259 (±)-Mevalonic acid 5-pyrophosphate tetralithium salt ≥80% (qNMR) Metabolite of the mevalonate pathway, which plays a key role in the biosynthesis of sterols, dolichol, heme and ubiquinone. Of interest for research in the disease areas oncology, autoimmune diseases, artherosclerosis and Alzheimer disease, as well as for inherited deficiencies of mevalonate kinase. Mevalonic acid 5-pyrophosphate was shown to elevate ubiquinone levels in rat liver tissues.
17943 (24R)-24,25-Dihydroxyvitamin D3 ≥98% (vitamin + pre-vitamin, HPLC) Cholecalciferol is an inactive form of vitamin D3 which undergoes various levels of hydroxylation to form active vitamin D3 analogs. 1α-Hydroxyvitamin D3 (alfacalcidol) is a synthetic analog that is metabolized to 1,25-dihydroxycholecalciferol, the biologically active form of vitamin D3. Other analogues of cholecalciferol result from different hydroxylations. 24R,25-Dihydroxyvitamin D3 is a catabolite of 25-Dihydroxyvitamin D3 and a putative regulator of developmental bone formation. 24R,25-Dihydroxyvitamin D3 is a substrate for renal 25-hydroxyvitamin D3 1 α-hydroxylase. 24R,25-Dihydroxyvitamin D3 is an endogenous regulator of apo A-I synthesis through a VDR-independent signaling mechanism and an inhibitor of Pi-induced apoptosis through Ca2+, PLD, and PLC signaling and through LPA-LPA1/3-G(αi)-PI(3)K-mdm2-mediated p53 degradation.
13368 1-Deoxy-D-xylulose-5-phosphate sodium salt ≥99.0% (TLC) Metabolite of the non-mevalonate pathway, generally found in prokaryotes, as precursor to isoprenoids as well as non-isoprenoids like vitamins. As this pathway is not present in humans, it is of interest for the development of bacterium-specific drugs in the search for treatments of infectious diseases.
H5002 17α-Hydroxypregnenolone  
17944 1α,25-Dihydroxyvitamin D2 ≥97.0% (sum of vitamin and previtamin, HPLC) Ergocalciferol (vitamin D2) is activated in vivo by hydroxylation to 25-hydroxyergocalciferol and 1α,25-dihydroxycalciferol. Activated Vitamin D2 molecules may be used in a wide range of studies to assess their effects on functions such as immune function and calcium homeostasis.
17936 1α,25-Dihydroxyvitamin D3 ≥97.0% (HPLC) Biologically active form of vitamin D3 in calcium absorption and deposition. 1α,25-Dihydroxyvitamin D3 has widespread effects on cellular differentiation and proliferation, and can modulate immune responsiveness, and central nervous system function. Recent studies suggest that 1α,25-dihydroxyvitamin D3 acts as a chemopreventive agent against several malignancies including cancers of the prostate and colon and shows synergy with other anticancer compounds.
17946 1α-Hydroxyvitamin D3 ≥97.0% (HPLC) Cholecalciferol is an inactive form of vitamin D3 which undergoes various levels of hydroxylation to form active vitamin D3 analogs. 1α-Hydroxyvitamin D3 (alfacalcidol is a synthetic analog that is metabolized to 1,25-dihydroxycholecalciferol, the biologically active form of vitamin D3 in calcium absorption and deposition. 1α,25-Dihydroxyvitamin D3 has widespread effects on cellular differentiation and proliferation, and can modulate immune responsiveness, and central nervous system function. Recent studies suggest that 1α,25-dihydroxyvitamin D3 acts as a chemopreventive agent against several malignancies including cancers of the prostate and colon and shows synergy with other anticancer compounds.
Synthetic vitamin D3 analog that is metabolized to 1,25-dihydroxycholecalciferol. Inhibits bone resorption and stimulates bone formation. Supresses parathyroid hormone secretion by bovine parathyroid cells.
41043 2,3-Oxidosqualene ≥92.0% (HPLC) 2,3-Oxidosqualene is a substrate of the 2,3-oxidosqualene cyclase lanosterol synthase. 2,3-oxidosqualene cyclase has been shown to be suppressed by a high fat diet and high levels of cholesterol.
52131 2-C-Methyl-D-erythritol 4-phosphate lithium salt ≥98% (TLC) Metabolite intermediate specific to the non-mevalonate MEP pathway, generally found in prokaryotes, as precursor to isoprenoids as well as non-isoprenoids like vitamins. As this pathway is not present in humans, it is of interest for the development of bacterium-specific drugs in the search for treatments of infectious diseases.
P9521 21-Deoxycortisol  
H9384   22(R)-Hydroxycholesterol ≥98% 22(R)-Hydroxycholesterol is an intermediate of the pregnenolone synthesis pathway from cholesterol. It reported has neuroprotective properties and protects the neurons against β-amyloid-induced cell death. 22(R)-Hydroxycholesterol acts as the ligand of liver X receptors that act as sensors of sterol concentration and regulates the fatty acid metabolism.
H5884 22(S)-Hydroxycholesterol 22(S)-Hydroxycholesterol modulates the lipid and glucose metabolism by acting on liver X receptors. It has the potential to reduce lipogenesis and the accumulation of lipid in hepatocytes, myotubes and non-adipose tissue.
P9129 5-Pregnen-3β-ol-20-one ≥98% One of a small number of "neurosteroids," steroids synthesized in the brain rather than peripheral sources. Decreased levels of these neurosteroids has been implicated in rodent cognitive decline with age, but studies in humans have been contradictory.
Testosterone production in rats occurs in Leydig cells of the testis via the Δ4 pathway. Cholesterol is first converted to pregnenolone, then to progesterone, and finally to testosterone. Pregnenolone is the key neurosteroid synthesized in steroidogenic glands. It is also present as a sulfate ester that serves as an antagonist of GABAergic neurons by interacting with γ-aminobutyric acid (GABA) receptor.
C3652 5α-Cholest-7-en-3β-ol 5α-Cholest-7-en-3β-ol (Lathosterol) is an intermediate in cholesterol biosynthesis pathway. Lathosterol in serum is carried on lipoproteins and is indicative of the rate of cholesterol synthesis. It acts as a marker of synthesis of cholesterol and is not affected by dietary consumption of cholesterol.
B4936 Brassicasterol from semisynthetic Brassicasterol is a phytosterol found in rapeseed and canola oils; it is also present in marine algae and shellfish. Brassicasterol has been shown to inhibit sterol Δ24-reductase, an enzyme involved in the mammalian cholesterol biosynthesis pathway.
Brassicasterol is a plant sterol, structurally similar to cholesterol. Plant sterols compete with cholesterol and reduce the content of cholesterol incorporated into micelles thereby reducing its absorption. Brassicasterol reportedly decreases the progression of atherosclerosis. The level of brassicasterol in cerebrospinal fluid may be used as a prognostic factor for progression of Alzheimer′s disease.
C5157 Campesterol ~65% Campesterol is a phytosterol, primarily found in nuts, fruits, legumes and seeds. Though an analogue of cholesterol, it is poorly absorbed in humans and competitively inhibits the absorption of cholesterol. Campesterol decreases the transcription of genes involved in cholesterol metabolism in hepatocytes and enterocytes and has positive impact in treatment of cardiovascular disease.
C9756 Cholecalciferol ≥98% (HPLC) Vitamin D acts through a receptor that is a member of the ligand-dependent transcription factor superfamily. Modulates the proliferation and differentiation of both normal and cancer cells. Has antiproliferative and antimetastatic effects on breast, colon, and prostate cancer cells. Activated vitamin D receptors in intestine and bone maintain calcium absorbance and homeostasis.
C8667 Cholesterol Sigma Grade, ≥99% Cholesterol is a lipid that makes up about 20-25% of the structural components of the cell membranes. It determines the fluidity and permeability of the membrane, making it permeable to water but not to ions and protons. Cholesterol also regulates the functions of the transporters and signaling proteins present on the plasma membrane. The major sites of cholesterol synthesis are small intestine and liver.
Major component of all biological membranes; ~25% of total brain lipid is cholesterol.
C8503 Cholesterol from sheep wool, ≥92.5% (GC), powder Cholesterol is a lipid makes up about 20-25% of the structural components of the cell membranes. It determines the fluidity and permeability of the membrane, making it permeable to water but not to ions and protons. Cholesterol also regulates the functions of the transporters and signaling proteins present on the plasma membrane. The major sites of cholesterol synthesis are small intestine and liver.
Major component of all biological membranes; ~25% of total brain lipid is cholesterol.
C8753 Cholesteryl arachidonate ≥95% (HPLC; detection at 205 nm), viscous liquid Cholesteryl arachidonate is a cholesterol ester found associated with the neutral core of low density lipoprotein. Receptor-LDL complexes are taken up by lysosomes and hydrolyzed to release cholesterol from the esters. The enzyme acid cholesteryl ester hydrolase is responsible for the hydrolysis of cholesteryl esters; a defective enzyme can result in the formation of atherosclerotic lesions in humans.
C0163 Cholesteryl dodecanoate ≥98% (HPLC; detection at 205 nm)  
C0289 Cholesteryl linoleate ≥98% (HPLC; detection at 205 nm) Cholesteryl linoleate is a major cholesterol ester found associated with the neutral core of low density lipoprotein. Receptor-LDL complexes are taken up by lysosomes and hydrolyzed to release cholesterol from the esters. The enzyme acid cholesteryl ester hydrolase is responsible for the hydrolysis of cholesteryl esters; a defective enzyme can result in the formation of atherosclerotic lesions in humans.
The most abundant cholesteryl ester in low density lipoprotein (LDL).
C9253 Cholesteryl oleate ≥98% (HPLC; detection at 205 nm) Cholesterol in plasma is present in an esterified form such as Cholesteryl oleate. The liver is a primary source of cholesteryl oleate that enriches the LDL particles when released into plasma. The secretion of lipoproteins enriched with cholesteryl oleate has close correlation with the pathogenesis of coronary artery atherosclerosis.
C6072 Cholesteryl palmitate ≥98% (HPLC; detection at 205 nm) Cholesteryl palmitate was used as standard in HPLC analysis of lipids from cooked ground beef and rat liver and mouse muscle tissue samples.
C2505 Corticosterone ≥92% Corticosterone is a glucocorticoid secreted by the adrenal cortex that activates both mineralocorticoid and glucocorticoid receptors.
C2755 Cortisone ≥98% Cortisone (11 dehydro 17 hydroxycortico-sterone) is an anti-inflammatory glucocorticoid that delays wound healing after surgeries. It postpones the healing process by affecting the appearance of inflammatory cells, ground substance, fibroblasts, collagen, regenerating capillaries, and epithelial migration. Glucocorticoids have anti-inflammatory, anti-allergic and immunosuppressive properties and are extensively used in treatment and therapy.
Cortisone is a glucocorticoid; a corticosterone analog that has approximately twice the anti-inflammatory potency as corticosterone but much lower Na2+ retention potency.
D6513 Desmosterol ≥84% (GC)  
D0196 Doxercalciferol ≥98% (HPLC), solubility: >10 mg/mL in DMSO Doxercalciferol is a Vitamin D2 analogue, a Vitamin D Receptor Activator (VDRA). Doxercalciferol acts as a pro-hormone, needing 25-hydroxylation in the liver for bioactivation into 1α, 25-hydroxyvitamin D2. Pivotal studies in adults on dialysis have demonstrated control of secondary hyperparathyroidism that is superior to placebo therapy, without undue suppression of 1st IMA-PTH < 300 pg/mL, or occurrences of hypercalcemia. Doxercalciferol has been shown to be effective in controlling secondary hyperparathyroidism of adult patients with CKD stages 3-4.
Doxercalciferol is a vitamin D2 analog that acts as a pro-hormone, activated in the liver to 1α,25-dihydroxyvitamin D2. Despite its relatively low affinity for the vitamin D receptor (VDR) (before activation), it is effective at suppressing expression of the parathyroid hormone (PTH) gene, and appears to act through the VDR.
95220 Ergocalciferol ≥98.0% (sum of enantiomers, HPLC) Ergocalciferol (vitamin D2) and 25-Hydroxycholecalciferol (vitamin D3) are the two form of vitamin D which are activated in vivo by hydroxylation. Vitamin D2 and D3 may be used in a wide range of studies to assess their effects on function such as immune function and calcium homeostasis.
E2634 Ergosta-5,7,9(11),22-tetraen-3β-ol ~96% (HPLC)  
E6510 Ergosterol ≥75%  
45480 Ergosterol ≥95.0% (HPLC) Ergosterol is a biological precursor of Vitamin D2 found in cell membranes of fungi and some protists such as trypanosomes. Ergosterol may be used to study the function of anti-fungal drugs such as Amphotericin B and its analogues and to study the ergosterol biosynthesis pathway within various fungi.
F6892 Farnesyl pyrophosphate ammonium salt methanol:ammonia solution, ≥95% (TLC) Isoprenoid from the intracellular mevalonate pathway used for prenylation of several low molecular mass G proteins, including Ras.
163333 Geraniol 98%  
G6772 Geranyl pyrophosphate ammonium salt 1 mg/mL in methanol (:aqueous 10 mM NH4OH (7:3)), ≥95% (TLC) Intermediate in terpene biosynthesis
G6025 Geranylgeranyl pyrophosphate ammonium salt solution, ≥95% (TLC), ~1 mg/mL in methanol: NH4OH (7:3) Isoprenoid from the intracellular mevalonate pathway used for prenylation of several low molecular weight G proteins, including Ras. Intermediate in terpene biosynthesis.
H0135 Hydrocortisone γ-irradiated, powder, BioXtra, suitable for cell culture Primary glucocorticoid secreted by the adrenal cortex. It has three times the anti-inflammatory potency of corticosterone but much lower Na2+ retention potency.
I0503 Isopentenyl pyrophosphate triammonium salt solution 1 mg/mL in methanol (:aqueous 10 mM NH4OH (7:3)), ≥95% (TLC)  
L5768 Lanosterol ≥93%, powder Cholesterol precursor sterol
S3626 Squalene ≥98%, liquid Biosynthetic precursor to all steroids. Cytoprotective to normal cells exposed to carcinogens and antitumor agents.
S2424 Stigmasterol ~95% Stigmasterol is a phytosterol with chemical structure similar to cholesterol. It exhibits anti-cancer, anti-pyretic, anti-inflammatory and immune-modulating effects. Stigmasterol decreases the expression of matrix metalloproteinases and reduced the degradation of cartilage in osteoarthritic rabbits.
S9889 β-Sitosterol from soybean, ≥96% Plant derived estrogen
S1270 β-Sitosterol synthetic, ≥95% A phytosterol with structure very similar to cholesterol that exhibits estrogenic activity. Inhibits proliferation of human leukemia cells, with G2/M arrest, endoreduplication, and polymerization of α-tubulin and microtubules.
D4287 γ,γ-Dimethylallyl pyrophosphate triammonium salt 1 mg/mL in methanol (:aqueous 10 mM NH4OH (7:3)), ≥90% (TLC) Intermediate in terpene biosynthesis
277541 trans,trans-Farnesol 96%