title: Induction of VMAT-1 and TPH-1 expression induces vesicular accumulation of serotonin and protects cells and tissue from cooling/rewarming injury.
abstract: DDT₁ MF-2 hamster ductus deferens cells are resistant to hypothermia due to serotonin secretion from secretory vesicles and subsequent cystathionine beta synthase (CBS) mediated formation of H₂S. We investigated whether the mechanism promoting resistance to hypothermia may be translationally induced in cells vulnerable to cold storage. Thus, VMAT-1 (vesicular monoamino transferase) and TPH-1 (tryptophan hydroxylase) were co-transfected in rat aortic smooth muscle cells (SMAC) and kidney tissue to create a serotonin-vesicular phenotype (named VTSMAC and VTkidney, respectively). Effects on hypothermic damage were assessed. VTSMAC showed a vesicular phenotype and an 8-fold increase in serotonin content and 5-fold increase in its release upon cooling. Cooled VTSMAC produced up to 10 fold higher concentrations of H₂S, and were protected from hypothermia, as shown by a 50% reduction of caspase 3/7 activity and 4 times higher survival compared to SMAC. Hypothermic resistance was abolished by the inhibition of CBS activity or blockade of serotonin re-uptake. In VTkidney slices, expression of CBS was 3 fold increased in cold preserved kidney tissue, with two-fold increase in H₂S concentration. While cooling induced substantial damage to empty vector transfected kidney as shown by caspase 3/7 activity and loss of FABP1, VTkidney was fully protected and comparable to non-cooled control. Thus, transfection of VMAT-1 and TPH-1 induced vesicular storage of serotonin which is triggered release upon cooling and has protective effects against hypothermia. The vesicular serotonergic phenotype protects against hypothermic damage through re-uptake of serotonin inducing CBS mediated H₂S production both in cells and kidney slices.
authors.affiliation: Department of Clinical Pharmacology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. Talaei@irimc.org
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Talaei
authors.forename: Martina
authors.initials: M
authors.lastname: Schmidt
authors.forename: Robert H
authors.initials: RH
authors.lastname: Henning
mesh_terms: D000818:Animals; D001011:Aorta / Q000473:pathology; D003094:Collagen / Q000378:metabolism; D006224:Cricetinae; D019610:Cytoprotection; D004790:Enzyme Induction; D006862:Hydrogen Sulfide / Q000378:metabolism; D007035:Hypothermia / Q000473:pathology / Q000517:prevention & control*; D007668:Kidney / Q000378:metabolism / Q000473:pathology; D008297:Male; D032389:Myocytes, Smooth Muscle / Q000201:enzymology / Q000473:pathology; D010641:Phenotype; D051381:Rats; D017207:Rats, Sprague-Dawley; D017694:Rewarming; D022142:Secretory Vesicles / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism*; D014162:Transfection; D014365:Tryptophan Hydroxylase / Q000096:biosynthesis*; D050493:Vesicular Monoamine Transport Proteins / Q000378:metabolism*
chemical_list: C493451:Slc18a1 protein, rat; D050493:Vesicular Monoamine Transport Proteins; D012701:Serotonin; D003094:Collagen; D014365:Tryptophan Hydroxylase; C504570:tph1 protein, rat; D006862:Hydrogen Sulfide