Efficacy of Sweet Pumpkin in Relieving Contact Dermatitis in Chronically Stressed Rats

Background: Contact dermatitis (CD) is considered among the common inflammatory skin diseases worldwide. Cucurbita moschata Duchesne has antioxidant, anti-inflammatory, and antidepressant activity beside many other beneficial effects.

Objectives: This study aimed to assess the effect of pumpkin fruit extract in treating CD in mice exposed to chronic stress and to explore the mechanism through which pumpkin can relief these changes.

Materials and methods: Thirty male albino rats were divided into three groups (n = 10); the control and two experimental groups that were exposure to chronic unpredictable mild stress for 4 weeks then painting with 1-fluoro-2,4-dinitrofluorobenzene (DNFB) for 3 consecutive days/week for 2 weeks to induce CD. Biochemical assessment of corticosterone level and antioxidants activity was performed. Skin of affected areas was excised, processed for histopathological examination.

Results: DNFB-induced CD presented with dryness, hardness, and scaling. There was a significant reduction (P < 0.001) in the levels of superoxide dismutase, glutathione peroxidase and catalase activity in the skin of rats had CD. Histopathologically, the shin showed hyperplastic-thickened epidermis, focal elongation of the rete ridges, inflammatory cells infiltration in the superficial dermis, and increased collagen fibers. Local administration of pumpkin extract significantly increased the antioxidants activity in the skin and alleviated the CD-associated changes.

Conclusions: This study showed that the pumpkin fruit extract could have a potential in treating CD in stressed conditions mainly via its enhancement of skin antioxidant activity.

Keywords: Antioxidants; chronic stress; contact dermatitis; corticosterone; pumpkin; superoxide dismutase.