Anti-inflammatory and/or immunomodulatory activities of Uncaria tomentosa (cat's claw) extracts: A systematic review and meta-analysis of in vivo studies

Gustavo Marin Arado; Pedro de Padua G Amatto; Mozart Marins; Elen Sanchez Rizzi; Suzelei de Castro França; Juliana da Silva Coppede; Fábio Carmona; Ana Maria Soares Pereira

doi:10.3389/fphar.2024.1378408

Anti-inflammatory and/or immunomodulatory activities of Uncaria tomentosa (cat's claw) extracts: A systematic review and meta-analysis of in vivo studies

Front Pharmacol. 2024 May 31:15:1378408. doi: 10.3389/fphar.2024.1378408. eCollection 2024.

Authors

Gustavo Marin Arado¹, Pedro de Padua G Amatto¹, Mozart Marins¹, Elen Sanchez Rizzi¹, Suzelei de Castro França¹, Juliana da Silva Coppede¹, Fábio Carmona², Ana Maria Soares Pereira¹

Affiliations

¹ Department of Biotechnology, University of Ribeirão Preto, Sao Paulo, Brazil.
² Department of Pediatrics, Ribeirao Preto Medical School, University of São Paulo, São Paulo, Brazil.

Abstract

Background: Uncaria tomentosa (Willd. ex Schult.) DC. (Rubiaceae) is traditionally used by Amazonian indigenous groups to treat inflammatory diseases. To date, there are no systematic reviews and meta-analyses on the use of U. tomentosa for inflammation control in animals supporting the traditional knowledge about this species. This study was conducted to evaluate the effect of U. tomentosa extracts in modulating inflammatory mediators and to determine which types of inflammatory diseases can be treated by this species.

Methods: We conducted a systematic review and meta-analysis of preclinical studies published before 26 July 2023, identified in PubMed, Embase, and Scopus. Four independent reviewers extracted the data and assessed the risks of bias. The effects of U. tomentosa on inflammatory diseases and the inflammatory mediators involved were extracted from the studies. Standardized mean differences (SMD) and 95% confidence intervals (95%CI) of the outcomes were estimated. The meta-analyses were conducted using RevMan 5.4 (Cochrane Collaboration). This protocol was registered in PROSPERO (CRD42023450869).

Results: Twenty-four of 523 studies were included. U. tomentosa extracts decreased the cytokines interleukin (IL)-6 (SMD: -0.72, 95%CI: -1.15, -0.29, p = 0.001) and transcription factor nuclear factor kappa-B (NF-κB) (SMD: -1.19, 95%CI: -1.89, -0.48, p = 0.001). However, the extracts did not significantly alter IL-1 (SMD: -0.16, 95%CI: -0.87, +0.56, p = 0.67), IL-10 (SMD: -0.05, 95%CI:-0.35, 0.45, p = 0.80), or tumor necrosis factor-alpha (TNF-α) levels (SMD: 0.18, 95%CI: -0.25, 0.62, p = 0.41).

Conclusion: Many extracts of stem bark, roots, and leaves of U. tomentosa, mostly aqueous and hydroethanolic, exhibited anti-inflammatory and/or immunomodulatory activities and low toxicity. The extracts decreased NF-κB and IL-6. These findings suggest that this species has the potential to treat inflammatory diseases in which these markers are increased, according to the ethnopharmacological use. These activities are not related to a specific class of compounds.

Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=450869, Identifier CRD42023450869.

Keywords: Rubiaceae; inflammation; inflammatory diseases; inflammatory mediators; medicinal plant.

Publication types

Systematic Review

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. The publication of this article was financially supported by the University of Ribeirao Preto (UNAERP).