17-β-Hydroxysteroid dehydrogenase X (HSD10) also known as 3-hydroxyacyl-CoA dehydrogenase type-2 is a mitochondrial enzyme that in humans is encoded by the HSD17B10 (hydroxysteroid (17β) dehydrogenase 10) gene. Several alternatively spliced transcript variants have been identified, but the full-length nature of only two transcript variants has been determined. Human HSD10 cDNA was cloned from brain (NM_004493), and the resulting protein, a homotetramer, was first characterized as a short chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD). Active sites of this enzyme can accommodate different substrates; 17β-HSD10 is involved in the oxidation of isoleucine, branched-chain fatty acids, and xenobiotics as well as the metabolism of sex hormones and neuroactive steroids.
The gene product is a mitochondrial protein that catalyzes the oxidation of a wide variety of fatty acids and steroids, and is a subunit of mitochondrial ribonuclease P, which is involved in tRNA maturation. The molecular weight of 17β-HSD10 that is composed of four identical subunits is 108 kDa; each subunit consists of 261 amino acid residues. Although the endoplasmic reticulum (ER)-associated amyloid-β peptide binding protein (ERAB) was reported to be associated with the ER and to consist of 262 residues with a molecular weight of 27 kDa, ERAB is actually identical to 17β-HSD10 that is localized in mitochondria but not ER.
Abnormal expression, as well as mutations of the HSD17B10 gene leads to impairment of the structure, function, and dynamics of mitochondria. This may underlie the pathogenesis of the synaptic and neuronal deficiency exhibited in 17β-HSD10 related diseases, including 17β-HSD10 deficiency and Alzheimer's disease (AD). Missense and silent mutations in the gene are the cause of hydroxysteroid (17β) dehydrogenase X (HSD10) deficiency, formerly MHBD deficiency, and X-linked mental retardation, choreoathetosis, and abnormal behavior (MRXS10), respectively. Restoration of steroid homeostasis could be achieved by the supplementation of neuroactive steroids with a proper dosing and treatment regimen or by the adjustment of 17β-HSD10 activity to protect neurons. The discovery of this enzyme's true function has opened a new therapeutic avenue for treating AD.
^ abHe XY, Merz G, Mehta P, Schulz H, Yang SY (May 1999). "Human brain short chain L-3-hydroxyacyl coenzyme A dehydrogenase is a single-domain multifunctional enzyme. Characterization of a novel 17beta-hydroxysteroid dehydrogenase". The Journal of Biological Chemistry. 274 (21): 15014–9. doi:10.1074/jbc.274.21.15014. PMID10329704.
^Holzmann J, Frank P, Löffler E, Bennett KL, Gerner C, Rossmanith W (Oct 2008). "RNase P without RNA: identification and functional reconstitution of the human mitochondrial tRNA processing enzyme". Cell. 135 (3): 462–74. doi:10.1016/j.cell.2008.09.013. PMID18984158.
^ abYan SD, Fu J, Soto C, Chen X, Zhu H, Al-Mohanna F, Collison K, Zhu A, Stern E, Saido T, Tohyama M, Ogawa S, Roher A, Stern D (Oct 1997). "An intracellular protein that binds amyloid-beta peptide and mediates neurotoxicity in Alzheimer's disease". Nature. 389 (6652): 689–95. doi:10.1038/39522. PMID9338779.
^ abcYang SY, He XY, Isaacs C, Dobkin C, Miller D, Philipp M (Sep 2014). "Roles of 17β-hydroxysteroid dehydrogenase type 10 in neurodegenerative disorders". The Journal of Steroid Biochemistry and Molecular Biology. 143: 460–72. doi:10.1016/j.jsbmb.2014.07.001. PMID25007702.
^He XY, Schulz H, Yang SY (Apr 1998). "A human brain L-3-hydroxyacyl-coenzyme A dehydrogenase is identical to an amyloid beta-peptide-binding protein involved in Alzheimer's disease". The Journal of Biological Chemistry. 273 (17): 10741–6. doi:10.1074/jbc.273.17.10741. PMID9553139.
^Beyreuther K, Masters CL (Oct 1997). "Alzheimer's disease. The ins and outs of amyloid-beta". Nature. 389 (6652): 677–8. doi:10.1038/39479. PMID9338775.
Vredendaal PJ, van den Berg IE, Malingré HE, Stroobants AK, Olde Weghuis DE, Berger R (Jun 1996). "Human short-chain L-3-hydroxyacyl-CoA dehydrogenase: cloning and characterization of the coding sequence". Biochemical and Biophysical Research Communications. 223 (3): 718–23. doi:10.1006/bbrc.1996.0961. PMID8687463.
Yang SY, He XY, Schulz H (Oct 2005). "3-Hydroxyacyl-CoA dehydrogenase and short chain 3-hydroxyacyl-CoA dehydrogenase in human health and disease". The FEBS Journal. 272 (19): 4874–83. doi:10.1111/j.1742-4658.2005.04911.x. PMID16176262.
Yang SY, He XY, Miller D (2007). "HSD17B10: a gene involved in cognitive function through metabolism of isoleucine and neuroactive steroids". Molecular Genetics and Metabolism. 92 (1-2): 36–42. doi:10.1016/j.ymgme.2007.06.001. PMID17618155.
Furuta S, Kobayashi A, Miyazawa S, Hashimoto T (Feb 1997). "Cloning and expression of cDNA for a newly identified isozyme of bovine liver 3-hydroxyacyl-CoA dehydrogenase and its import into mitochondria". Biochimica et Biophysica Acta. 1350 (3): 317–24. doi:10.1016/s0167-4781(96)00171-6. PMID9061028.
He XY, Schulz H, Yang SY (Apr 1998). "A human brain L-3-hydroxyacyl-coenzyme A dehydrogenase is identical to an amyloid beta-peptide-binding protein involved in Alzheimer's disease". The Journal of Biological Chemistry. 273 (17): 10741–6. doi:10.1074/jbc.273.17.10741. PMID9553139.
Hansis C, Jähner D, Spiess AN, Boettcher K, Ivell R (Nov 1998). "The gene for the Alzheimer-associated beta-amyloid-binding protein (ERAB) is differentially expressed in the testicular Leydig cells of the azoospermic by w/w(v) mouse". European Journal of Biochemistry / FEBS. 258 (1): 53–60. doi:10.1046/j.1432-1327.1998.2580053.x. PMID9851691.
Oppermann UC, Salim S, Tjernberg LO, Terenius L, Jörnvall H (May 1999). "Binding of amyloid beta-peptide to mitochondrial hydroxyacyl-CoA dehydrogenase (ERAB): regulation of an SDR enzyme activity with implications for apoptosis in Alzheimer's disease". FEBS Letters. 451 (3): 238–42. doi:10.1016/S0014-5793(99)00586-4. PMID10371197.
Yang SY, He XY (2001). "Role of type 10 17beta-hydroxysteroid dehydrogenase in the pathogenesis of Alzheimer's disease". Advances in Experimental Medicine and Biology. 487: 101–10. doi:10.1007/978-1-4615-1249-3_8. PMID11403151.
Frackowiak J, Mazur-Kolecka B, Kaczmarski W, Dickson D (Jul 2001). "Deposition of Alzheimer's vascular amyloid-beta is associated with decreased expression of brain L-3-hydroxyacyl-coenzyme A dehydrogenase (ERAB)". Brain Research. 907 (1-2): 44–53. doi:10.1016/S0006-8993(01)02497-0. PMID11430884.
He XY, Merz G, Yang YZ, Mehta P, Schulz H, Yang SY (Sep 2001). "Characterization and localization of human type10 17beta-hydroxysteroid dehydrogenase". European Journal of Biochemistry / FEBS. 268 (18): 4899–907. doi:10.1046/j.0014-2956.2001.02421.2421.x. PMID11559359.
He XY, Wen GY, Merz G, Lin D, Yang YZ, Mehta P, Schulz H, Yang SY (Feb 2002). "Abundant type 10 17 beta-hydroxysteroid dehydrogenase in the hippocampus of mouse Alzheimer's disease model". Brain Research. Molecular Brain Research. 99 (1): 46–53. doi:10.1016/S0169-328X(02)00102-X. PMID11869808.