title: Ultrasonography reveals in vivo dose-dependent inhibition of end systolic and diastolic volumes, heart rate and cardiac output by nesfatin-1 in zebrafish.
abstract: Nesfatin-1 is an 82 amino acid peptide that inhibits food intake in rodents and fish. While endogenous nesfatin-1, and its role in the regulation of food intake and hormone secretion has been reported in fish, information on cardiovascular functions of nesfatin-1 in fish is in its infancy. We hypothesized that cardiac NUCB2 expression is meal responsive and nesfatin-1 is a cardioregulatory peptide in zebrafish. NUCB2/nesfatin-1 like immunoreactivity was detected in zebrafish cardiomyocytes. Real-time quantitative PCR analysis found that the cardiac expression of NUCB2A mRNA in unfed fish decreased at 1h post-regular feeding time. Food deprivation for 7days did not change NUCB2A mRNA expression. However, NUCB2B mRNA expression was increased in the heart of zebrafish after a 7-day food deprivation. Ultrasonography of zebrafish heart at 15min post-intraperitoneal injection of nesfatin-1 (250 and 500ng/g body weight) showed a dose-dependent inhibition of end diastolic and end systolic volumes. A dose dependent decrease in heart rate and cardiac output was observed in zebrafish that received nesfatin-1, but no changes in stroke volume were found. Nesfatin-1 treatment caused a significant increase in the expression of Atp2a2a mRNA encoding the calcium-handling pump, SERCA2a, while it had no effects on the expression of calcium handling protein RyR1b encoding mRNA. Our data support cardiosuppressive effects of nesfatin-1 in zebrafish, and reveals energy availability as one determinant of cardiac NUCB2 mRNA expression.
authors.affiliation: Laboratory of Integrative Neuroendocrinology, Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, Canada.
authors.forename: Neelima
authors.initials: N
authors.lastname: Nair
authors.affiliation: Laboratory of Integrative Neuroendocrinology, Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, Canada.
authors.forename: Courtney
authors.initials: C
authors.lastname: Gerger
authors.affiliation: Laboratory of Integrative Neuroendocrinology, Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, Canada.
authors.forename: Azadeh
authors.initials: A
authors.lastname: Hatef
authors.affiliation: Laboratory of Integrative Neuroendocrinology, Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, Canada.
authors.forename: Lynn P
authors.initials: LP
authors.lastname: Weber
authors.affiliation: Laboratory of Integrative Neuroendocrinology, Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, Canada. Electronic address: suraj.unniappan@usask.ca.
authors.forename: Suraj
authors.initials: S
authors.lastname: Unniappan
mesh_terms: D000818:Animals; D002135:Calcium-Binding Proteins / Q000187:drug effects*; D002302:Cardiac Output / Q000187:drug effects*; D004268:DNA-Binding Proteins / Q000187:drug effects*; D003971:Diastole / Q000187:drug effects*; D006321:Heart / Q000000981:diagnostic imaging*; D006339:Heart Rate / Q000187:drug effects*; D009419:Nerve Tissue Proteins / Q000187:drug effects* / Q000378:metabolism; D000080866:Nucleobindins; D013599:Systole / Q000187:drug effects*; D014463:Ultrasonography / Q000379:methods*; D015027:Zebrafish
chemical_list: D002135:Calcium-Binding Proteins; D004268:DNA-Binding Proteins; D009419:Nerve Tissue Proteins; D000080866:Nucleobindins
keywords: Heart; Nesfatin-1; Nucleobindin-2; Ultrasound; Zebrafish