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Title: Inhibition of TNF-α in hypothalamic paraventricular nucleus attenuates hypertension and cardiac hypertrophy by inhibiting neurohormonal excitation in spontaneously hypertensive rats

We hypothesized that chronic inhibition of tumor necrosis factor-alpha (TNF-α) in the hypothalamic paraventricular nucleus (PVN) delays the progression of hypertension and attenuates cardiac hypertrophy by up-regulating anti-inflammatory cytokines, reducing pro-inflammatory cytokines (PICs), decreasing nuclear factor-κB (NF-κB) p65 and NAD(P)H oxidase activities, as well as restoring the neurotransmitters balance in the PVN of spontaneously hypertensive rats (SHR). Adult normotensive Wistar–Kyoto (WKY) and SHR rats received bilateral PVN infusion of a TNF-α blocker (pentoxifylline or etanercept) or vehicle for 4 weeks. SHR rats showed higher mean arterial pressure and cardiac hypertrophy compared with WKY rats, as indicated by increased whole heart weight/body weight ratio, whole heart weight/tibia length ratio, left ventricular weight/tibia length ratio, and cardiac atrial natriuretic peptide (ANP) and beta-myosin heavy chain (β-MHC) mRNA expressions. Compared with WKY rats, SHR rats had higher PVN levels of tyrosine hydroxylase, PICs, the chemokine monocyte chemoattractant protein-1 (MCP-1), NF-κB p65 activity, mRNA expressions of NOX-2 and NOX-4, and lower PVN levels of IL-10 and 67-kDa isoform of glutamate decarboxylase (GAD67), and higher plasma norepinephrine. PVN infusion of pentoxifylline or etanercept attenuated all these changes in SHR rats. These findings suggest that SHR rats have an imbalance between excitatory and inhibitory neurotransmitters, asmore » well as an imbalance between pro- and anti-inflammatory cytokines in the PVN; and chronic inhibition of TNF-α in the PVN delays the progression of hypertension by restoring the balances of neurotransmitters and cytokines in the PVN, and attenuating PVN NF-κB p65 activity and oxidative stress, thereby attenuating hypertension-induced sympathetic hyperactivity and cardiac hypertrophy. - Highlights: • Spontaneously hypertensive rats exhibit neurohormonal excitation in the PVN. • PVN inhibition of TNF-α attenuates hypertension-induced cardiac hypertrophy. • PVN inhibition of TNF-α attenuates hypertension-induced neurohormonal excitation. • PVN inhibition of TNF-α attenuates hypertension-induced imbalance of cytokines. • PVN inhibition of TNF-α attenuates PVN NF-κB p65 activity and oxidative stress.« less
Authors:
;  [1] ;  [2] ;  [1] ;  [3] ;  [4] ;  [1] ;  [5] ;  [6] ;  [7] ;  [1]
  1. Department of Physiology and Pathophysiology, Xi'an Jiaotong University Cardiovascular Research Center, Xi'an Jiaotong University School of Medicine, Xi'an 710061 (China)
  2. Department of Endocrinology and Metabolism, First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an 710061 (China)
  3. Department of Cardiovascular Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032 (China)
  4. Department of Cardiovascular Medicine, First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an 710061 (China)
  5. Key Laboratory of Remodeling-related Cardiovascular Diseases, Department of Pathology, School of Basic Medical Sciences, Capital Medical University, Beijing 100069 (China)
  6. Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing 210029 (China)
  7. Department of Neurosurgery, First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an 710061 (China)
Publication Date:
OSTI Identifier:
22439913
Resource Type:
Journal Article
Resource Relation:
Journal Name: Toxicology and Applied Pharmacology; Journal Volume: 281; Journal Issue: 1; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; COMPARATIVE EVALUATIONS; DECARBOXYLASES; EXCITATION; HEART; HYDROXYLASES; HYPERTENSION; HYPERTROPHY; INFLAMMATION; LYMPHOKINES; MESSENGER-RNA; MONOCYTES; MYOSIN; NORADRENALINE; OXIDASES; OXIDATION; PEPTIDES; RATS; TIBIA; TYROSINE