Volume 16 Supplement 1

Abstracts from the 7th International Conference on cGMP Generators, Effectors and Therapeutic Implications

Open Access

C-type natriuretic peptide chronic administration attenuates cardiac fibrosis and inflammation in spontaneously hypertensive rats

  • E Santos Prentki1Email author,
  • C Caniffi1,
  • G Bouchet1,
  • D Maglio González2,
  • J Toblli3,
  • MA Costa1 and
  • C Arranz1
BMC Pharmacology and Toxicology201516(Suppl 1):A104

https://doi.org/10.1186/2050-6511-16-S1-A104

Published: 2 September 2015

Background

Growing evidence shows that the expression and release of a number of inflammatory cytokines are increased in hypertension [1, 2] and are also present at sites of cardiovascular fibrosis. In fact, many of these inflammatory mediators are responsible for the activation of collagen producing fibroblasts [3]. In addition, proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-α) and interleukin-1 (IL-1) have shown to stimulate the release of C-type natriuretic peptide (CNP), indicating a potential role of CNP as a modulator of the inflammatory process [4]. The aim of the present study was to evaluate the effects of chronic CNP treatment on cardiac fibrosis and inflammation in spontaneously hypertensive rats (SHR).

Experimental design and methods

12-week-old male SHR and Wistar rats were infused through osmotic pumps with CNP (0,75 µg/hr) or saline (S) for 14 days. Systolic blood pressure (SBP, mmHg) was recorded by tail-cuff method. At the end of the treatment, the left ventricle (LV) was extracted to determine left ventricular mass index (LVMI, g LV/mm tibia length), the myocyte area (µm2, Haematoxylin and Eosin-stain), fibrosis (% collagen, Picrosirius Red stain) and inflammation parameters (IL-6 and TNF-α, % stain/mm2 by immunohistochemistry, IHC and IL-6, TNF-α and IL-1β, pg/mg protein by ELISA).

Results

Table 1

 

W-S

W-CNP

SHR-S

SHR-CNP

SBP

118±2

122±3

175±3*

159±5#

LMVI

0,023±0,002

0,024±0,001

0,032±0,001*

0,029±0,001

Myocyte area

349±11

337±10

609±25*

557±35#

% Fibrosis

1,54±0,53

1,78±0,17

6,81±0,40*

3,27±0,67#

IL-6 (IHC)

1,8±1,0

1,3±0,6

19,4±2,7*

2,1±0,7#

TNF-α (IHC)

1,1±0,7

1,0±0,5

15,7±3,4*

1,5±0,9#

IL-6 (ELISA)

--

--

100,1±6,2

81,0±9,0

TNF-α (ELISA)

--

--

8,27±0,89

4,32±0,18#

IL-1β (ELISA)

--

--

135,7±5,8

120,3±2,3#

Values are means ± SEM.

*p<0.01 vs W-S,

# p<0.01 vs SHR-S.

Conclusions

Characteristic high SBP values in SHR are accompanied by hypertrophy, fibrosis and a higher presence of inflammatory cytokines.

Our results show that chronic treatment with CNP attenuates the expression of proinflammatory markers and the early signs of fibrosis in cardiac tissue of hypertensive rats. These effects, combined with the drop in blood pressure we observed, indicate that CNP could possibly have an important pathophysiological and therapeutical role in preventing or even reversing cardiac fibrosis and inflammation accompanying left ventricular remodelling in arterial hypertension.

Authors’ Affiliations

(1)
Physiology, School of Pharmacy and Biochemistry, IQUIMEFA-CONICET, University of Buenos Aires
(2)
Immunology, School of Pharmacy and Biochemistry, IDEHU-CONICET, University of Buenos Aires
(3)
Laboratory of Experimental Medicine, German Hospital

References

  1. Sanz-Rosa D, Oubiña MP, Cediel E, de Las Heras N, Vegazo O, Jiménez J, Lahera V, Cachofeiro V: Effect of AT1 receptor antagonism on vascular and circulating inflammatory mediators in SHR: role of NF-kappaB/IkappaB system. Am J Physiol Heart Circ Physiol. 2005, 288: H111-H115.View ArticlePubMedGoogle Scholar
  2. Dinh QN, Drummond GR, Sobey CG, Chrissobolis S: Roles of inflammation, oxidative stress, and vascular dysfunction in hypertension. Biomed Res Int. 2014, 2014: 406960-View ArticlePubMedPubMed CentralGoogle Scholar
  3. Lee SB, Kalluri R: Mechanistic connection between inflammation and fibrosis. Kidney Int Suppl. 2010, 119: S22-S26.View ArticlePubMedGoogle Scholar
  4. Osterbur K1, Yu DH, DeClue AE: Interleukin-1β, tumour necrosis factor-α and lipopolysaccharide induce C-type natriuretic peptide from canine aortic endothelial cells. Res Vet Sci. 2013, 94: 478-83. 10.1016/j.rvsc.2012.10.002.View ArticlePubMedGoogle Scholar

Copyright

© Prentki et al. 2015

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Advertisement