Elsevier

Phytomedicine

Volume 16, Issue 12, December 2009, Pages 1101-1104
Phytomedicine

Effects of Pinus brutia bark extract and Pycnogenol® in a rat model of carrageenan induced inflammation

https://doi.org/10.1016/j.phymed.2009.05.004Get rights and content

Abstract

The present study was conducted to explore the anti-inflammatory activities of Pinus brutia bark extract and Pycnogenol® in a rat model of carrageenan-induced inflammation. Firstly, the compositions of both samples were determined using HPLC. Then, carrageenan-induced paw edema was used to assess anti-inflammatory activity in mice. Paw volume was measured before and 1, 2, 3, 4, 5 and 6 h after the injection of carrageenan. Intraperitoneal administration of both the extract and Pycnogenol® inhibited paw swelling dose-dependently at 2, 3, 4, 5 and 6 h after carrageenan injection. Both samples exhibited significant anti-inflammatory activities at doses of 75 and 100 mg/kg body wt. between 2 and 4 hours after administration (p<0.05), respectively. Additionally, P. brutia bark extract showed significantly better activity at doses of 75 and 100 mg/kg body wt. than indomethacine at the dose of 10 mg/kg body wt. (p<0.05). No acute toxicity was identified in intraplantar injection of the extract at a dose of 2000 mg/kg body wt.. Therefore, P. brutia bark extract possessing 3.3-fold more total catechins and 9.8-fold more taxifolin than Pycnogenol® can be utilized as an anti-inflammatory agent.

Introduction

The history of utilization of pine barks dates back to ancient times. The first reported Indian cure was in the winter of 1535 in Canada when the members of a crew were dying from scurvy. The almost instant cure comprised a decoction of bark and leaves from conifers. Treatments of wounds using the bark of spruce, pine and juniper was also known at that time. Interest stimulated by these reports initiated research on pine bark extract (Rohdewald 2002) and it has found wide application in the fields of nutrition, health and over the past few decades. Pine bark extracts have received considerable attention because of their anti-inflammatory, antimutagenic, anticarcinogenic, and high antioxidant activity. The most common commercially available pine bark extract is Pycnogenol®, a standardized extract of French maritime pine bark (Pinus maritima) which is probably the most studied phenolic tree extract containing the naturally occurring chemicals called proanthocyanidins. Proanthocyanidins have antioxidant (Jerez et al. 2007; Guri et al. 2006), anti-inflammatory (Schafer et al. 2005), anticarcinogenic (Horakova et al. 2003; Packer et al. 1999), and immune-modulating (Liu et al. 1998) activities and have been reported to significantly affect circulation, inflammation and immune response (Packer et al. 1999). Blaszo et al. have also reported that proanthocyanidins accelerate the wound healing process and serve as potent active ingredients for the treatment of minor injuries (Blazso et al. 2004).

The anti-inflammatory mechanisms of Pycnogenol® have been elucidated in a variety of in vitro and cell culture studies (Rohdewald 2002; Packer et al. 1999). Inhibition of localized inflammation was also investigated in various in vivo studies (Mochizuki and Hasegawa 2004; Sime and Reeve 2004; Blazso et al. 1997). Thus, there is evidence from several in vivo and in vitro studies that supplementation with French maritime pine bark extract improves inflammatory symptoms.

Although French maritime pine bark has been investigated intensively, there exist comparatively fewer literature reports on the anti-inflammatory activities of different pine bark species. In one published study, the effects of the pine bark crude extract, chloroform fraction and a preparative fraction prepared from P. sylvestris were measured and it was shown that P. sylvestris contained compounds which inhibited the production of nitric oxide and prostaglandin E2, proinflammatory mediators (Karonen et al. 2004).

The aim of this research study was to identify the compositions and compare the anti-inflammatory activities of a bark extract from Pinus brutia and Pycnogenol® in a rat model of carrageenan-induced inflammation. To the best of our knowledge, as confirmed through a review of the literature, the anti-inflammatory activity of Pinus brutia bark extract has not yet been studied.

Section snippets

Plant material and Pycnogenol®

Pinus brutia Ten. has spread out in eastern Mediterranean countries and is distributed widely in several regions in Turkey (Davis 1978–1988). Pine bark (P. brutia) was collected from Izmir-Deliomer (N: 38°10′17.0″ E: 27°03′46.7″, altitude: 120 m) in August 2006. The specimen was dried at room temperature, ground using a conventional grinder and stored at +4 °C. A voucher specimen is kept at IZEF Herbarium (IZEF 5762). Pycnogenol® was generously donated by Horphag Research Ltd., UK.

Preparation of pine bark extract

Pine bark

Results and discussion

Firstly, compositions of the samples were determined and compared using HPLC (Fig. 1). According to the results, P. brutia bark extract contained 5.3-fold more (−)-catechin and 9.8-fold more taxifolin, whereas Pycnogenol® had 2.3- and 2.6-fold more (−)-epicatechin and (−)-catechin gallate. Total catechin contents of P. brutia bark extract were 3.3-fold higher than those of Pycnogenol® (Table 1).

The next step was to determine dose-dependent suppression of carrageenan-induced paw edema. P. brutia

Conclusion

Based on these results, it can be concluded that intraperitoneal administration of P. brutia bark extract resulted in an anti-inflammatory effect very like the reported activity of Pycnogenol® (Blazso et al. 1997; Liu et al. 1998; Saliou et al. 2001). Wagner and Ulrich-Merzenich (2009) mentioned the importance of ongoing projects aimed at the development of new phytopharmaceuticals. Utilization of P. brutia bark extracts as a therapeutic agent can contribute to the achievement of this goal.

Acknowledgements

This project was supported by the Research Fund of Ege University (06MUH007). Special thanks to Horphag Research Ltd., UK for the donation of Pycnogenol®.

References (26)

  • M.S.E. Bayeta et al.

    Pycnogenol inhibits generation of inflammatory mediators in macrophages

    Nutr. Res.

    (2000)
  • S. Benito et al.

    A flavonoid-rich diet increases nitric oxide production in rat aorta

    Br. J. Pharmacol.

    (2002)
  • P.H. Davis
    (1978–1988)
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