<i>Pterocarpus angolensis</i> crude extracts induce the expression of collagen Type II in articular cartilage <i>in vitro</i>

Abstract

Background: Pterocarpus angolensis (P. angolensis) is a large deciduous tree native to Sub-Saharan Africa. This tree has traditionally been used to treat malaria, gonorrhoea, inflammation and wounds. The use of P. angolensis for tissue engineering has not been explored. This study investigated the potential of the bark and root water extracts of P. angolensis to induce the expression of collagen type II protein in the articular chondrocytes. Materials and Methods: Surface and middle zone chondrocytes, as well as explants, were stimulated with crude root and bark plant extracts at different concentrations. After 96 hours of stimulation, microscopic observation, XCELLigence assay and collagen type II ELISA, histology and immunohistochemistry assays were done. Results and Conclusion: Results showed no significant difference in the cell index between the controls and chondrocytes that had been treated with the plant extracts at concentrations of 15 and 30 µg/ml. A significant increase in the expression of collagen type II protein by the chondrocytes was observed and found to be optimal at a concentration of 30 µg/ml. There was an increase in the production of proteoglycans. However, the plant extracts at a concentration of 50 µg/ml induced apoptosis in the middle zone chondrocytes. These results show the potential of P. angolensis extracts in chondrocyte tissue regeneration. This potential could be exploited in the treatment of osteoarthritis. Keywords: P. angolensis, medical plants, chondrocytes, collagen type II, arthritis IntroductionPterocarpus angolensis (P. angolensis), also known as moroto (Sotho) or umbilo (Zulu), is a large deciduous tree native to the Sub-Saharan African region (Cameron et al., 2009;Geldenhuys, 2013;van Wyk & van Wyk, 2013).This tree usually grows to about 16 meters tall, has a dark brown bark and a high, wide, crowned canopy of shiny compound leaves. Wood from P. angolensis has been used to make furniture because of its resistance to termites and borer (Geldenhuys, 2013). Besides furniture, this tree has traditionally been used to treat diseases and medical conditions such as malaria, gonorrhea, ringworm, skin inflammation, wounds, stomach ache and poor breast milk supply (Geldenhuys, 2013;van Wyk & van Wyk, 2013).The use of P. angolensis to heal wounds suggests that this tree contains compounds that stimulate the regeneration of torn tissue. The regeneration of torn tissue in humans has been linked to an increase in the expression of compounds such as hyaluronan, chondroitin sulphate, aggrecan and collagen (Fraser et al., 2003;Greco et al., 1998;Ko et al., 2009;Wood, 1960).Collagen is the main structural protein of various connective tissues in animals. This protein is produced by cell types derived from mesenchyme such as fibroblasts, osteoblasts, chondroblasts and smooth muscle cells. Chondrocytes are responsible for the production of collagen found within the cartilage matrix. Collagen type II in particular is the principal component of articular cartilage and has various bene...

The Potential Effect of Medicinal Plants for Cartilage Regeneration

“…However, the plant extracts at a 50 μg/ml induced apoptosis in the middle zone chondrocytes. In conclusion the findings of this study are of great importance in understanding the mechanisms through which P. angolensis enables the healing of breached tissue [21]. In our laboratory, an (unpublished) in vitro study has observed the enhancement of proliferation and osteogenic differentiation (by increasing alkaline phosphate activity) of C2C12 myoblast cells treated with Pleurostylia capensis crude extract.…”

Phytochemicals from Pterocarpus angolensis DC and Their Cytotoxic Activities against Breast Cancer Cells

“…The (DCM/Methanol v / v , 50%) extract of P. angolensis inhibited Plasmodium falciparum chaperones (PfHsp70-z and PfHsp70-1), with IC 50 values of 13.87 and 0.20 µg/mL, respectively [ 14 ]. The crude aqueous extracts of bark and root from P. angolensis enabled the healing of breached tissue and induced an increase in chondrogenesis [ 15 ]. According to our knowledge, no anticancer activities have been reported on the extracts and isolated compounds of P. angolensis .…”

Medicinal Plants in Tissue Engineering and Regenerative Medicine in the African Continent

“…These plant extracts are also being incorporated in the fabrication of biomaterial scaffolds used in tissue engineering and regenerative medicine. [16][17][18][19] These scaffolds will not only act as medium to transport cells/materials inside or outside the human body, but also take part in the regeneration and activation of cells owing to their plant morphogenetic factor content.…”

“…In fact, plant extracts are currently seen as potential solutions in the treatment of chronic wounds and speeding up acute healing, reducing longer hospital stay of patients with bone fracture problems due to accidents and medical conditions. They could furthermore act as anti-inflammatory agents in inflammatory diseases as well as alleviate or accelerate OA healing and other joint diseases by increasing collagen type II production in tissue engineering and re-generative medicine, [16][17][18] besides being useful in the pharmaceutical sector for drug production for the treatment of numerous illnesses.…”