Objective: Morinda citrifolia L. is a traditional Polynesian medicinal plant which is apparently useful for bowel disorders, skin inflammation, infection, mouth ulcers and wound healing. This study aimed to evaluate the wound-healing activity of Morinda citrifolia fruit juice in streptozotocin-induced diabetic rats.
Method: An excision wound model was used. The animals were weight-matched and placed into three groups (n = 6 per group). Group 1 animals served as normal controls, while animals in groups 2 and 3 served as diabetic controls and experimental diabetic animals respectively. All animals were anaesthetised and a full-thickness excision wound (circular area of 300 mm2 and 2 mm deep) was created. Group 3 animals were given the juice of Morinda citrifolia fruit (100 ml per kilogram of body weight) in their drinking water for 10 days. Wound area measurements were taken on days 1, 5 and 11. Blood samples were collected simultaneously for glucose measurement. Granulation tissue that had formed on the wound was excised on day 11 and processed for histological and biochemical analysis.
Results: The wound area of the Morinda citrifolia-treated group reduced by 73% (p < 0.001) when compared with the diabetic controls (63%). Significant increases in the weight of granulation tissue (p < 0.001) and hydroxyproline content (p < 0.00 1, 92.16 +/- 4.02) were observed. The protein content was moderately high. Histological studies showed that collagen was laid down faster in the experimental diabetic animals than in the normal control and diabetic control groups. Fasting blood glucose values in the diabetic experimental group had reduced by 29% (p < 0.00 1) compared with the diabetic control animals. There was a good correlation between the wound contraction rate and blood glucose values.
Conclusion: This study demonstrates that the juice of Morinda citrifolia fruit significantly reduces blood sugar levels and hastens wound healing in diabetic rats.