Protective effects of Aloe sterols against UVB-induced photoaging in hairless mice.

BACKGROUND: Aloe vera is a traditional medical plant whose gel has been widely used in skin care. Previously, we have identified Aloe sterols from Aloe vera as active ingredients. This study investigated the protective effects of Aloe sterols without polysaccharides, against ultraviolet B (UVB)-induced skin photoaging in mice using Aloe vera gel extract (AVGE) obtained by supercritical fluid extraction. METHODS: Aloe vera gel extract was supplemented in the diet (12 or 120 ppm), and HR-1 hairless mice were exposed to UVB irradiation for 7 weeks. Skin measurements and histological and analytical studies were performed. RESULTS: Repeated UVB irradiation induced rough wrinkling of skin with water content reduction and hyperkeratosis. AVGE administration resulted in the significant improvement of UVB-induced skin dryness, epidermal thickness, and wrinkle formation. The AVGE group also suppressed the degenerations of dermal collagen fibers and the appearance of cutaneous apoptosis cells induced by UVB. Furthermore, AVGE administration reduced the excess elevation of pro-inflammatory cytokines (IL-1ß and TNF-α) and matrix metalloproteinases (MMP-2, MMP-9, MMP-12, and MMP-13) in UVB-exposed skin. CONCLUSION: The dietary ingestion of Aloe sterols protected against chronic UVB damage in mouse skin, and our results suggest that Aloe sterols may prevent skin photoaging through the anti-inflammation and MMP regulation.

Oral administration of Aloe vera gel powder prevents UVB-induced decrease in skin elasticity via suppression of overexpression of MMPs in hairless mice.

This study reports the effects of oral Aloe vera gel powder (AVGP) containing Aloe sterols on skin elasticity and the extracellular matrix in ultraviolet B (UVB)-irradiated hairless mice. Ten-week-old hairless mice were fed diets containing 0.3% AVGP for 8 weeks and irradiated UVB for 6 weeks. Mice treated with AVGP showed significant prevention of the UVB-induced decrease in skin elasticity. To investigate the mechanism underlying this suppression of skin elasticity loss, we measured the expression of matrix metalloproteinase (MMP)-2, -9, and -13. AVGP prevented both the UVB-induced increases in MMPs expressions. Moreover, we investigated hyaluronic acid (HA) content of mice dorsal skin and gene expression of HA synthase-2 (Has2). In the results, AVGP oral administration prevented UVB-induced decreasing in skin HA content and Has2 expression and attenuates the UVB-induced decrease in serum adiponectin, which promotes Has2 expression. These results suggested that AVGP has the ability to prevent the skin photoaging.

Aloe vera gel extract attenuates ethanol-induced hepatic lipid accumulation by suppressing the expression of lipogenic genes in mice.

We have previously reported that Aloe vera gel had hypoglycemic activity and anti-obesity effects, although the effect on alcoholic fatty liver was unclear. We examined in this present study the effect of an Aloe vera gel extract (AVGE) on hepatic lipid metabolism by using an ethanol-induced transient fatty liver mouse model. Ethanol (3 g/kg of mouse weight) was orally administered to induce an accumulation of triglyceride (TG) and increase the mRNA expression of such lipogenic genes as sterol regulatory element-binding protein-1 (SREBP-1) and fatty acid synthase (FASN) in the liver. Although ethanol ingestion caused a 5.4-fold increase in liver TG, pre-treating with AVGE (1 mg/kg/d) for 1 week significantly suppressed this elevation of the ethanol-induced liver TG level. The expression of lipogenic genes was also lower in the AVGE pre-treatment group than in the control group. This inhibitory effect on the ethanol-induced accumulation of TG was attributed to a reduction in the expression of lipogenic genes that were increased by ethanol.

Comparative study of short-term anxiolytic potency of alprazolam and tandospirone in psychiatric outpatients with anxiety disorders.

Anxiolytic potency of 1 week of treatment with alprazolam or tandospirone in psychiatric outpatients with anxiety disorders was evaluated by changes in the scores on the Hamilton Anxiety Scale and the State and Trait Anxiety Inventory and in the saliva level of free-3-methoxy-4-hydroxyphenylglycol (free-MHPG). Saliva level of free-MHPG was significantly reduced by 1 week of treatment with alprazolam but not with tandospirone. Reductions in the HAS score after 1 week of drug treatment were greater in patients treated with alprazolam than in those treated with tandospirone. These results indicate that the short-term anxiolytic potency of alprazolam is greater than that of tandospirone and that the saliva level of MHPG would be a useful marker for the evaluation of the therapeutic potency of anxiolytic agents. Copyright 2001 John Wiley & Sons, Ltd.