Anti-inflammatory and antitumoural effects of Uncaria guianensis bark

J Ethnopharmacol. 2013 Dec 12;150(3):1154-62. doi: 10.1016/j.jep.2013.10.055. Epub 2013 Nov 7.


Ethnopharmacological relevance: Uncaria guianensis (Aublet) Gmell (Rubiaceae) is a medicinal plant from the jungles of South and Central America, used to treat cancer, arthritis, diabetes, and inflammation. Evaluate the anti-inflammatory and anti-tumor effects of Uncaria guianensis preparations.

Materials and methods: Bio-guided fractionation of a hydroethanolic extract of Uncaria guianensis was performed, evaluating the fractions and subfractions for their effect on inflammatory mediators, tumour necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and prostaglandin E2 (PGE2) by ELISA and nitric oxide (NO) by the Griess reaction in cultured supernatant from RAW 264.7 macrophages stimulated with lipopolysaccharide (LPS). The expression of cyclooxygenase 2 (COX-2), inducible nitric oxide synthase (iNOS) and inhibitor of κB (IκB) were investigated in RAW 264.7 macrophages by flow cytometry. The activity of NF-κB in HeLa cells transfected with a luciferase reporter system was determined. The effect of Uncaria guianensis on the inflammatory response in vivo was assessed in BALB/c mice stimulated with LPS, on rat paw oedema induced by carrageenan, and on tumour growth and lung metastasis in BALB/c mice inoculated with 4T1 mammary tumour cells. Immune cell infiltrates and inflammatory mediators were evaluated in the tumour by immunohistochemistry.

Results: Sub-fraction Ug AIV inhibited, to varying degrees, NO, TNF-α, IL-6 and PGE2 production by macrophages in vitro (30 μg/ml) and in the serum of LPS-challenged mice (5 mg/kg). Macrophage expression of Cox-2 was inhibited (35%), IκB degradation was completely inhibited and NF-κB activation was inhibited (70%) by Ug AIV at 30 μg/ml. Ug AIV decreased paw oedema by 86% (5 mg/kg) and serum NO and TNF-α by 45% and 65% respectively. Ug AIV reduced 4T1 mammary tumour growth by 91% on day 33 post-inoculation as well as the levels of serum NO, IL-6 and TNF-α in the same animals. Ug AIV decreased the number of tumour-infiltrating T lymphocytes, macrophages and neutrophils as well as the number of cells positive for COX-2, iNOS, IL-6, TNF-α and p65.

Conclusions: As Ug AIV was not cytotoxic for tumour cells or macrophages, its anti-tumour effect may be due to a reduction in pro-tumoural inflammatory processes in the tumour microenvironment, possibly mediated through NF-κB.

Keywords: COX-2; IL; Il-6; IκB; LPS; NF-κB; NO; PGE(2); TNF-α; cyclooxygenase 2; iNOS; inducible nitric oxide synthase; inhibitor of κB; interleukin; lipopolysaccharide; nitric oxide; prostaglandin E(2); tumour necrosis factor alpha.

MeSH terms

  • Animals
  • Anti-Inflammatory Agents* / pharmacology
  • Anti-Inflammatory Agents* / therapeutic use
  • Antineoplastic Agents* / pharmacology
  • Antineoplastic Agents* / therapeutic use
  • Breast Neoplasms / drug therapy
  • Breast Neoplasms / pathology
  • Carrageenan
  • Cell Line
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Dinoprostone / metabolism
  • Edema / chemically induced
  • Edema / drug therapy
  • Female
  • Humans
  • I-kappa B Proteins / metabolism
  • Inflammation / chemically induced
  • Inflammation / drug therapy
  • Interleukin-6 / metabolism
  • Lipopolysaccharides
  • Lung Neoplasms / drug therapy
  • Lung Neoplasms / secondary
  • Male
  • Mice
  • Mice, Inbred BALB C
  • NF-KappaB Inhibitor alpha
  • NF-kappa B / metabolism
  • Nitric Oxide / metabolism
  • Nitric Oxide Synthase Type II / antagonists & inhibitors
  • Nitric Oxide Synthase Type II / metabolism
  • Phytotherapy
  • Plant Bark
  • Plant Extracts* / pharmacology
  • Plant Extracts* / therapeutic use
  • Rats, Sprague-Dawley
  • Tumor Necrosis Factor-alpha / metabolism
  • Uncaria*


  • Anti-Inflammatory Agents
  • Antineoplastic Agents
  • I-kappa B Proteins
  • Interleukin-6
  • Lipopolysaccharides
  • NF-kappa B
  • NFKBIA protein, human
  • Nfkbia protein, mouse
  • Nfkbia protein, rat
  • Plant Extracts
  • Tumor Necrosis Factor-alpha
  • interleukin-6, mouse
  • NF-KappaB Inhibitor alpha
  • Nitric Oxide
  • Carrageenan
  • Nitric Oxide Synthase Type II
  • Nos2 protein, mouse
  • Dinoprostone