TMAO, a seafood-derived molecule, produces diuresis and reduces mortality in heart failure rats
Abstract
Trimethylamine-oxide (TMAO) is present in seafood which is considered to be beneficial for health. Deep-water animals accumulate TMAO to protect proteins, such as lactate dehydrogenase (LDH), against hydrostatic pressure stress (HPS). We hypothesized that TMAO exerts beneficial effects on the circulatory system and protects cardiac LDH exposed to HPS produced by the contracting heart. Male, Sprague-Dawley and Spontaneously-Hypertensive-Heart-Failure (SHHF) rats were treated orally with either water (control) or TMAO. In vitro, LDH with or without TMAO was exposed to HPS and was evaluated using fluorescence correlation spectroscopy. TMAO-treated rats showed higher diuresis and natriuresis, lower arterial pressure and plasma NT-proBNP. Survival in SHHF-control was 66% vs 100% in SHHF-TMAO. In vitro, exposure of LDH to HPS with or without TMAO did not affect protein structure. In conclusion, TMAO reduced mortality in SHHF, which was associated with diuretic, natriuretic and hypotensive effects. HPS and TMAO did not affect LDH protein structure.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all figures and tables.
Article and author information
Author details
Funding
Narodowe Centrum Nauki (2018/31/B/NZ5/00038.)
- Marcin Ufnal
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: The study was performed according to Directive 2010/63 EU on the protection of animals used for scientific purposes and approved by the Local Bioethical Committee in Warsaw (permission:100/2016 and 098/2019).
Reviewing Editor
- Arduino A Mangoni, Flinders Medical Centre, Australia
Publication history
- Received: March 19, 2020
- Accepted: June 7, 2020
- Accepted Manuscript published: June 8, 2020 (version 1)
- Version of Record published: July 3, 2020 (version 2)
Copyright
© 2020, Gawrys-Kopczynska et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Funding: RD is supported by the National Institute of General Medical Sciences of the National Institutes of Health (NIH) (R35-GM124836) and the National Heart, Lung, and Blood Institute of the NIH (R01-HL139865 and R01-HL155915).
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Clinical trial identifier: NCT05016622.