RESUMO
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.
RESUMO
OBJECTIVES: This study aimed to assess the impact of high cholesterol diet (HCD)-induced hypercholesterolemia on the rat thyroid gland and investigate the role of grape juice (GJ) in reducing such impact through biochemical and histopathological methods. MATERIALS AND METHODS: Thirty male Wistar rats sorted into three groups (the control, HCD-fed group, and the HCD+GJ fed group for 13 weeks) were used in this study. Lipid profile, blood glucose and insulin, thyroid hormones, some oxidants/antioxidants parameters were assessed. After the end of the experiment, thyroid glands were dissected out and processed for histopathological assessment using the light and electron microscopy. RESULTS: Based on the lipid profile, HCD induced hypercholesterolemia in rats after 13 weeks. This resulted in significant (p<0.001) increase of the levels of insulin, blood glucose, thyroid-stimulating hormone (TSH) (596.4±17 IU∕mL), thyroxine (T4) (202.8±14.1 ng∕mL) and malondialdehyde (MDA) (21.2±4.9 nmol∕mg protein), while the levels of triiodothyronine (T3) (12.6±1.9 ng∕mL) and total antioxidant capacity (TAOC) (21.2±4.9 U∕mg protein) decreased in HCD-fed rats compared to that of the controls. Structurally, thyroid gland follicles of HCD-fed rats showed cytoplasmic vacuolation, stratification and increased thickness of some lining cells. Ultrastructurally, some of follicular and parafollicular cells showed heterochromatic nuclei, degenerated mitochondria, intracytoplasmic lipid droplets and deposition of collagen fibers between the follicles. GJ could improve the lipid and antioxidants profiles, reduced blood glucose level, thyroid hormones, and alleviated the HCD-induced structural changes in the thyroid. CONCLUSIONS: GJ administrated simultaneously with HCD ameliorated the negative impact of the function and structure of the thyroid.
