Tongxinluo Protects against Hypertensive Kidney Injury in Spontaneously-Hypertensive Rats by Inhibiting Oxidative Stress and Activating Forkhead Box O1 Signaling

PLoS One. 2015 Dec 16;10(12):e0145130. doi: 10.1371/journal.pone.0145130. eCollection 2015.

Abstract

Hypertension is an independent risk factor for the progression of chronic renal failure, and oxidative stress plays a critical role in hypertensive renal damage. Forkbox O1(FoxO1) signaling protects cells against oxidative stress and may be a useful target for treating oxidative stress-induced hypertension. Tongxinluo is a traditional Chinese medicine with cardioprotective and renoprotective functions. Therefore, this study aimed to determine the effects of Tongxinluo in hypertensive renal damage in spontaneously hypertensive rats(SHRs)and elucidate the possible involvement of oxidative stress and FoxO1 signaling in its molecular mechanisms. SHRs treated with Tongxinluo for 12 weeks showed a reduction in systolic blood pressure. In addition to increasing creatinine clearance, Tongxinluo decreased urinary albumin excretion, oxidative stress injury markers including malondialdehyde and protein carbonyls, and expression of nicotinamide adenine dinucleotide phosphate oxidase subunits and its activity in SHR kidneys. While decreasing phosphorylation of FoxO1, Tongxinluo also inhibited the phosphorylation of extracellular signal-regulated kinase1/2 and p38 and enhanced manganese superoxide dismutase and catalase activities in SHR kidneys. Furthermore, histology revealed attenuation of glomerulosclerosis and renal podocyte injury, while Tongxinluo decreased the expression of α-smooth muscle actin, extracellular matrixprotein, transforming growth factor β1 and small mothers against decapentaplegic homolog 3,and improved tubulointerstitial fibrosis in SHR kidneys. Finally, Tongxinluo inhibited inflammatory cell infiltration as well as expression of tumor necrosis factor-α and interleukin-6. In conclusion, Tongxinluo protected SHRs against hypertension-induced renal injury by exerting antioxidant, antifibrotic, and anti-inflammatory activities. Moreover, the underlying mechanisms of these effects may involve inhibition of oxidative stress and functional activation of FoxO1 signaling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antioxidants / pharmacology*
  • Antioxidants / therapeutic use
  • Catalase / metabolism
  • Cytokines / metabolism
  • Drugs, Chinese Herbal / pharmacology*
  • Drugs, Chinese Herbal / therapeutic use
  • Forkhead Transcription Factors / metabolism*
  • Hypertension, Renal / drug therapy*
  • Male
  • Mitogen-Activated Protein Kinase 1 / metabolism
  • Mitogen-Activated Protein Kinase 3 / metabolism
  • Nerve Tissue Proteins / metabolism*
  • Oxidative Stress*
  • Proteinuria / drug therapy
  • Rats
  • Rats, Inbred SHR
  • Rats, Wistar
  • Superoxide Dismutase / metabolism
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • Antioxidants
  • Cytokines
  • Drugs, Chinese Herbal
  • Forkhead Transcription Factors
  • Nerve Tissue Proteins
  • tongxinluo
  • Foxo1 protein, rat
  • Catalase
  • Superoxide Dismutase
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • p38 Mitogen-Activated Protein Kinases

Grants and funding

This work was supported by the National 973 Basic Research Program of China, www.973.gov.cn (no. 2012CB518603 to YXZ), the National Natural Science Foundation of China, www.nsfc.gov.cn (30873325, 81100103, 81173251, 81302939 to YXZ), and the Shandong Province Medical Science and Technology Development Plan, www.sdwsjs.gov.cn (2014WS0147 to RXY). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.