Selenium is an essential micronutrient which functions as an essential constituent of selenoproteins. The selenoproteins play an important role in the body’s defense from free radicals associated with chronic diseases such as cancer. The effect of selenium on colon carcinogenesis was investigated using an experimental animal model. Five-week old ICR mice were acclimated for one week, and fed on the Fe-overloaded diet (450 ppm) with different Se diets (0.02, 0.1 or 0.5 ppm) for 12 weeks. Animals were injected intraperitoneally with azoxymethane (AOM, 10 mg/㎏ B.W. weekly for 3 weeks), followed by 2% dextran sodium sulfate (DSS) in the drinking water for a week. There were three experimental groups including low Se group (Lse), medium (normal standard diet for mice) Se (MSe), and high Se (HSe). The numbers of aberrant crypt foci (ACF) and aberrant crypt (AC) were measured in the colonic mucosa. The iron and selenium concentrations in liver was measured using ICP-AES. Glutathione peroxidase (GPx) activity was determined in the liver and colon. TUNEL assay for cell apoptosis and proliferating cell nuclear antigen (PCNA) staining for cell proliferation were performed. Immunohistochemical staining of β-catenin was also performed in mucous tissue of colon. The dietary Se decreased the numbers of ACF/㎠ and AC/㎠ in a dose-dependent manner. HSe diet significantly decreased the numbers of AC/㎠, compared with LSe diet (p<0.05). The tumor incidence rate in low Se diet group was 5% higher than medium Se diet group and 20% higher than high Se diet group. The activities of GPx in the liver and colon were dependent on the content of dietary selenium. Apoptosis-positive cells were also increased by dietary Se in a dose-dependent manner. PCNA-positive staining was weak in high Se group. β-catenin stained area was increased in low Se group while it was decreased in high Se group. These findings indicate that dietary selenium exert a protecting effect on colon cancer by inhibiting the development of ACF/AC, increasing GPX and apoptosis, and decreasing cell proliferation and expression of β-catenin in mice.
Wrinkles are an outward sign of cutaneous aging appearing preferentially on ultraviolet B (UVB)-exposed areas. The anti-wrinkle effects of herbal extracts were investigated in an animal model. Female albino hairless mice (HR/ICR) were randomly allocated to the control group (non-irradiated vehicle), positive control group (UVB irradiated-vehicle), and two herbal extract mixture groups (HE-1 and HE-2). HE-1 included Glycyrrhizae radix, Rhei Rhizoma, Cornus officinalis, and Sesami semeni, and HE-2 included Swertia pseudo-chinensis, Sophora flavescens, Scutellaria baicalensis, and Salvia miltiorrhiza. The herbal extract mixtures were pre-treated dorsally with 0.2 ml per individual five times per week for four weeks prior to the start of UVB irradiation. At the fifth week, the animals were exposed to UVB irradiation for a subsequent eight weeks, three times per week. The intensity of irradiation showed a gradual increase, from 30 mJ/cm 2 to 240 mJ/cm2 (1 MED: 60 mJ/cm2 ). Dorsal skin samples were stained with H&E in order to examine the epidermal thickness. In addition, Masson-Trichrome staining was performed for determination of the amount of collagen fiber. Treatments with HE-1&2 resulted in an increase in the amount of collagen fiber, a better appearance, and fewer wrinkles, compared with the positive control. As determined by hydroxyproline assay, treatments with HE-1&2 led to a significant increase in the amount of collagen, compared with the positive control group (p<0.05). Chronic UVB irradiation to skin of hairless mice resulted in an increase in expression of matrix metalloproteinase-1 (MMP-1), however, treatments with HE-1&2 tended to decrease the expression of MMP-1. These results indicate that the herbal extracts used in this study have a preventive effect on UVB-induced wrinkle formation in a hairless mouse model, due in part to inhibition of MMP-1 expression and increment of collagen amount.
Although hair disorders are not life threatening, a lot of people who suffer hair loss and/or hair thinning is increasing in accordance with changes in lifestyle and nutritional balance. The aim of this study was to examine the effects of herbal extracts on hair regrowth in C3H/HeJ mice. There were 6 experimental groups including distilled water (D.W.), 50% ethanol (a vehicle control), 3% minoxidil (a positive control), and 3 kinds of herbal extracts mixtures (C, D & E). The test compounds included followings; C : Glycyrrhizae radix, Rhei Rhizoma, Cornus officinalis and Sesami semeni, D : Viticus fructus, Pulsatilla chinensis, Gardenia fructus and Artemisiae argyi herb, E : Swertia pseudo-chinensis, Sophora flavescens Scutellaria baicalensis and Salvia miltiorrhiza. The animals were shaved with an electric clipper. The test compounds were daily treated to dorsal skin with 0.2 ml per mouse for 3 weeks. The topical application of the E test solution accelerated hair regrowth after 10 days faster than that of the positive and vehicle controls. The activities of alkaline phosphatase (ALP) and γ-glutamyl transpeptidase significantly were increased in all the treatment groups after 3 weeks, compared with D.W. group. Especially, the E test solution notably increased ALP activity compared with positive or vehicle control group. Epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) were increased in all the treatment groups after 3 weeks compared with D.W. group. These results suggest that the herbal extracts have hair regrowth effect by increasing enzyme activities and growth factors and it can be useful for treatment for alopecia in humans.