The Effect of Virgin Coconut and Black Cumin Oils on TNF-alpha Expression and Histopathological in Diabetic Rat Wound Healing

Background: Wound healing is a multifaceted process requiring the collaboration of various elements to facilitate the repair of damaged tissue. To accelerate healing process, Virgin Coconut Oil (VCO) and black cumin oil are plant oils that have been proven to offer several beneficial pharmacological effects. Therefore, this study aimed to determine the effect of VCO and black cumin oil, as well as their combination, on expression of TNF-α and histopathological features during wound healing process in diabetic rat. Methods: Rat were injected with streptozotocin (55 mg/kg BW) and a 10 mm wound was created (n=30). Subsequently, rat was randomly divided into six groups (n=5), consisting of control (Untreated), VCO, black cumin oil, C1, C2, and C3 groups. Topical oil application was performed once daily for 14 days. Wound healing between groups was evaluated using visual observation, with hematoxylin and eosin staining. Meanwhile, TNF-α gene expression was analyzed using RT-PCR on days 7 and 14, followed by data analysis with one-way ANOVA. Results: The C1 group receiving a topical application of a combination of VCO and black cumin oil showed a moderate wound closure pattern characterized by good shape, thickest epidermis, higher granulation, greater collagen density, and fibroblast, with lower inflammatory cell infiltration compared to others. The combination of VCO and black cumin oil in the C2 and C3 groups significantly decreased TNF-α gene expression on day 7. In contrast, on day 14, the C3 group significantly reduced TNF-α expression compared to the control group. Regarding histopathological features, the C1 group provided the optimal wound healing process compared to others.Conclusion: The combination of VCO and black cumin oil accelerated wound healing process by inducing a decrease in TNF-α expression and providing an intermediate healing pattern.