Knowra Steroidogenesis Steroidogenesis Steroidogenesis is the synthesis of steroid hormones from cholesterol through enzyme-catalyzed reactions. It occurs chiefly in the adrenal cortex and gonads, with distinct pathways producing glucocorticoids, mineralocorticoids, and sex steroids.
Cholesterol side-chain cleavage enzyme : A mitochondrial enzyme that converts cholesterol into pregnenolone, the precursor of all steroid hormones. It catalyzes the first committed step in steroid hormone synthesis.
Cholesterol : A sterol lipid that forms cell membranes and serves as the precursor for steroid hormones, bile acids, and vitamin D. It supplies the carbon framework from which every steroid hormone is made.
Cortisol : A glucocorticoid hormone that helps regulate metabolism, immune activity, and responses to stress. It is the principal glucocorticoid product of adrenal steroidogenesis.
Peptide hormone : A hormone composed of amino acids, usually synthesized as a precursor and stored in secretory vesicles. Unlike steroid hormones, peptide hormones are not built from cholesterol.
Pregnenolone : A steroid intermediate formed from cholesterol and the precursor to progesterone and other steroid hormones. It is the first steroid product made in the pathway.
Mitochondrion : A membrane-bound cell organelle where cellular respiration and several metabolic reactions take place. The first and some final steroidogenic reactions occur in mitochondria.
Aldosterone : A mineralocorticoid hormone that promotes sodium retention and potassium excretion in the kidneys. Its synthesis branches from shared precursors in the adrenal cortex.
Catecholamine : A class of hormones and neurotransmitters synthesized from the amino acid tyrosine. Catecholamines arise from amino-acid chemistry rather than steroid pathways.
3β-Hydroxysteroid dehydrogenase : An enzyme that converts Δ5 steroid intermediates into Δ4 steroids, including pregnenolone into progesterone. It directs intermediates toward several major hormone pathways.
Smooth endoplasmic reticulum : A membrane network involved in lipid synthesis, detoxification, and calcium storage. Many steroidogenic enzymes are embedded in its membranes.
Show all 21