Gentiopicroside Ameliorates Diabetic Peripheral Neuropathy by Modulating PPAR- Γ/AMPK/ACC Signaling Pathway

Cell Physiol Biochem. 2018;50(2):585-596. doi: 10.1159/000494174. Epub 2018 Oct 11.

Abstract

Background/aims: Gentiopicroside is promising as an important secoiridoid compound against pain. The present study aimed to investigate the analgesic effect and the probable mechanism of Gentiopicroside on Diabetic Peripheral Neuropathy (DPN), and to figure out the association among Gentiopicroside, dyslipidemia and PPAR- γ/AMPK/ACC signaling pathway.

Methods: DPN rat models were established by streptozotocin and RSC96 cells were cultured. Hot, cold and mechanical tactile allodynia were conducted. Blood lipids, nerve blood flow, Motor Nerve Conduction Velocity (MNCV) and Sensory Nerve Conduction Velocity (SNCV) were detected. Gene and protein expression of PPAR- γ/AMPK/ACC pathway was analyzed by reverse transcription-quan titative polymerase chain reaction (RT-qPCR) and Westernblot. Besides, PPAR-γ antagonist GW9662 and agonist rosiglitazone, AMPK antagonist compound C and activator AICAR as well as ACC inhibitor TOFA were used to further confirm the relationship between PPAR-γ and AMPK.

Results: The results demonstrated that Gentiopicroside markedly ameliorated hyperalgesia with prolonged paw withdrawal latency to heat and cold stimuli and fewer responses to mechanical allodynia compared with DPN model group. Gentiopicroside regulated dyslipidemia, enhanced nerve blood flow and improved MNCV as well as SNCV. Gentiopicroside suppressed ACC expression through the activation of AMPK and PPAR-γ mediated the activation of AMPK and subsequent inhibition of ACC expression.

Conclusion: In conclusion, the present study demon strated that Gentiopicroside exerted nerve-protective effect and attenuated experimental DPN by restoring dyslipidmia and improved nerve blood flow through regulating PPAR-γ/AMPK/ACC signal pathway. These results provided a promising potential treatment of DPN.

Keywords: AMPK; Diabetic peripheral neuropathy (DPN); Gentiopicroside; PPAR-γ.

MeSH terms

  • AMP-Activated Protein Kinases / genetics
  • AMP-Activated Protein Kinases / metabolism*
  • Acetyl-CoA Carboxylase / genetics
  • Acetyl-CoA Carboxylase / metabolism*
  • Anilides / pharmacology
  • Animals
  • Blood Flow Velocity / drug effects
  • Diabetic Neuropathies / chemically induced
  • Diabetic Neuropathies / pathology
  • Diabetic Neuropathies / prevention & control*
  • Diabetic Neuropathies / veterinary
  • Dyslipidemias / pathology
  • Dyslipidemias / prevention & control
  • Dyslipidemias / veterinary
  • Female
  • Gene Expression Regulation / drug effects
  • Hyperalgesia / pathology
  • Hyperalgesia / prevention & control
  • Hyperalgesia / veterinary
  • Iridoid Glucosides / pharmacology
  • Iridoid Glucosides / therapeutic use*
  • PPAR gamma / genetics
  • PPAR gamma / metabolism*
  • Protective Agents / pharmacology
  • Protective Agents / therapeutic use*
  • Rats
  • Rats, Sprague-Dawley
  • Schwann Cells / cytology
  • Schwann Cells / drug effects
  • Schwann Cells / metabolism
  • Signal Transduction / drug effects
  • Streptozocin / toxicity

Substances

  • 2-chloro-5-nitrobenzanilide
  • Anilides
  • Iridoid Glucosides
  • PPAR gamma
  • Protective Agents
  • gentiopicroside
  • Streptozocin
  • AMP-Activated Protein Kinases
  • Acetyl-CoA Carboxylase