Repressive effect of Rhus coriaria L. fruit extracts on microglial cells-mediated inflammatory and oxidative stress responses

J Ethnopharmacol. 2021 Apr 6:269:113748. doi: 10.1016/j.jep.2020.113748. Epub 2020 Dec 24.

Abstract

Ethnopharmacological relevance: Rhus coriaria L. represents a herbal shrub that is used widely in traditional medicine in the Middle East region to treat different diseases including inflammation-related disorders. R. coriaria extracts have been well characterized in terms of their biological activities, pharmacological potential and phytochemical components. However, the effect of R. coriaria on neuro-inflammation has not been studied previously in detail.

Aim of the study: In the present study, we performed a qualitative phytochemical analysis and investigated the antioxidant and anti-neuro-inflammatory potential of R. coriaria extracts on BV-2 microglial cells.

Materials and methods: R. coriaria extracts were prepared using two different solvents: distilled water and ethanol. Phytochemical screening was performed to determine the principal bioactive components. The radical scavenging activity was assessed by DPPH method (2,2-diphenyl-1-picrylhydrazyl). The effect of R. coriaria on neuro-inflammation was studied upon measuring the production of oxidative stress and inflammatory factors using DCF (2',7'-dichlorofluorescein) and Nitric oxide (NO) assays respectively, and by analyzing the mRNA (TNFα, IL-10, iNOS and COX-2) and protein (NFκβ) levels of genes involved BV-2 microglia cells-mediated inflammation using quantitative Real Time PCR and Western blot, respectively.

Results: We found that R. coriaria extracts contain high phenolic and flavonoid contents. Interestingly, the ethanolic extract exerted a potent anti-inflammatory potential on insulted BV-2 cells manifested by: i) inhibition of Reactive Oxygen species (ROS) production and nitric oxide (NO) release; ii) suppressing TNFα, iNOS and COX-2 mRNA levels; iii) reducing NFκβ activation; and iiii) enhancing IL-10 transcription levels.

Conclusion: Our results indicate that the neuro-inflammation inhibitory activity of R. coriaria extracts involves the inhibition of NF-κB signaling pathway. These findings suggest that R. coriaria might carry therapeutic potential against neurodegenerative diseases.

Keywords: Anti-inflammatory; Anti-oxidant; Microglia; Neurodegenerative diseases; Rhus coriaria.

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / pharmacology*
  • Antioxidants / pharmacology
  • Cell Line
  • Cell Survival / drug effects
  • Cyclooxygenase 2 / genetics
  • Cytoprotection / drug effects
  • Free Radical Scavengers / pharmacology
  • Fruit
  • Inflammation / chemically induced
  • Inflammation / drug therapy*
  • Interleukin-10 / genetics
  • Mice
  • Microglia / drug effects
  • Middle East
  • NF-kappa B p50 Subunit / metabolism
  • Nervous System Diseases / chemically induced
  • Nervous System Diseases / drug therapy*
  • Nitric Oxide / metabolism
  • Nitric Oxide Synthase Type II / genetics
  • Oxidative Stress / drug effects*
  • Phytochemicals / chemistry
  • Phytochemicals / pharmacology*
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Reactive Oxygen Species / metabolism
  • Rhus / chemistry*
  • Tumor Necrosis Factor-alpha / genetics

Substances

  • Anti-Inflammatory Agents
  • Antioxidants
  • Free Radical Scavengers
  • IL10 protein, mouse
  • NF-kappa B p50 Subunit
  • Phytochemicals
  • Plant Extracts
  • Reactive Oxygen Species
  • Tumor Necrosis Factor-alpha
  • Interleukin-10
  • Nfkb1 protein, mouse
  • Nitric Oxide
  • Nitric Oxide Synthase Type II
  • Nos2 protein, mouse
  • Ptgs2 protein, mouse
  • Cyclooxygenase 2