Effect of antioxidant treatment with n-acetylcysteine and swimming on lipid expression of sebaceous glands in diabetic mice.

The sebaceous gland (SG) is involved in different inflammatory, infectious and neoplastic processes of the skin and can be related to specific diseases, e.g., diabetes mellitus. Sometimes, the histological diagnosis requires complementary tests due to the ability of diseases to mimic other tumors. We evaluated the sebaceous gland density in Non-obese diabetic mice to analyze the N-acetylcystein effects and swimming exercise treatment in sebaceous glands healing, using specific staining in histochemistry and immunohistochemistry reactions in the identification of the lipid expression in the sebaceous gland. We investigated the intracytoplasmic lipid expression and analysis of gland density from SG in dorsal skin samples from the Non-obese diabetic (NOD mice) and diabetic animals submitted to antioxidant treatment and physical exercise. For histological analysis of the sebaceous glands, specific staining in histochemistry with sudan black and immunohistochemistry reaction with adipophilin were used in the evaluation. Statistical analysis showed significant proximity between the values of the control group and the diabetic group submitted to the swimming exercise (DS group) and similar values between the untreated diabetic group (UD group) and diabetic group treated with the antioxidant N-acetylcysteine (DNa group), which did not prevent possible differences where p < 0.01. Adipophilin (ADPH) immunohistochemistry permitted more intense lipid staining in SGs, the preservation of the SG in the control group, and a morphological deformed appearance in the UD and DNa groups. However, weak morphological recovery of the SG was observed in the DS-Na group, being more expressive in the DS group. In conclusion, the groups submitted to physical exercises showed better results in the recovery of the analyzed tissue, even being in the physiological conditions caused by spontaneous diabetes.

Blockade of S100A3 activity inhibits murine hair growth.

Using mouse gene expression microarray analysis, we obtained dynamic expression profiles of the whole genome in a depilation-induced hair growth mouse model. S100A3 expression increased during the anagen phase and returned to normal during the telogen phase. The effects of S100A3 blockade on the hair growth cycle were examined in mice after subcutaneous injection of an anti-mouse S100A3 antibody. Protein localization of S100A3 was confined to the hair shafts during the anagen phase and the sebaceous glands during the telogen phase. S100A3 blockade delayed hair follicle entry into the anagen phase, decreased hair elongation, and reduced the number of hair follicles in the subcutis, which correlated with the downregulated expression of hair growth induction-related genes in vivo. The present study demonstrates that anti-S100A3 antibody inhibits mouse hair growth, suggesting that S100A3 can be used as a target for hair loss treatment.

Effect of carbamates on mRNA encoding lipid enzymes in hamster flank organs.

Flank organs are an androgen-dependent pilosebaceous complex present in male and female hamsters. These organs have been used for the evaluation of antiandrogenic drugs, which could be used for the treatment of androgen-dependent afflictions. This study demonstrated the role of four different steroidal carbamates 7-10 in the expression of mRNAs coding for different enzymes involved in the lipid metabolism in flank organs. To determine the biological effects of compounds 7-10 on the expression of mRNA coding for lipid enzymes, steroids 7-10, testosterone (T), progesterone (P), and/or 7-10 were applied on the flank organs. Later, the mRNA expression for the enzymes was determined by polymerase chain reaction. The binding of 8 and 9 to the progesterone receptor (PR) as well as their effects on the activity of 5α-reductase were also evaluated. Treatments with T, P, and 7-10 increased the mRNA expression for glycerol 3-phosphate acyl transferase (GPAT), ß-hydroxy-ß-methylglutaryl-CoA synthase (HMG-CoA-S), ß-hydroxy-ß-methylglutaryl-CoA reductase (HMG-CoA-R), phosphatidylinositol synthase (PI-S), and squalene-synthase (SQ-S). However, the combined treatments with P + 7-10 decreased the expression of GPAT, HMG-CoA-S, and HMG-CoA-R. Expression of mRNA for all enzymes was variable under treatment with T + 7-10. Data showed that these carbamates did not bind to the PR, but inhibited the activity of 5α-reductase. Carbamates 7-10 changed the mRNA expression model induced by T and P in flank organs.

Molecular interactions of natural and synthetic steroids in female hamsters' flank organs.

BACKGROUND: The initial step of steroidal action on target cells is gene activation; therefore, the quantification of mRNA is a direct method for comparing the role of different steroids in the skin. OBJECTIVE: This study demonstrated the role of several steroids on the mRNA expression encoding for different enzymes involved in the lipid metabolism in hamsters' flank organs, which are a pilosebaceous complex. METHODS: To determine the effect of treatments with testosterone (T) progesterone (P), levonorgestrel (LNG), 17α-p-chlorobenzoyloxy-6-chloropregn-4,6-diene-3,20-dione (5) and 17α-p-chlorobenzoyloxy-4,6-pregnadiene-3,20-dione (6); T and/or LNG; T and 5 or 6; P and/or 5 or 6 on the expression of mRNA encoding for lipid enzymes, the steroids were applied to the glands; later, the mRNAs expression for the enzymes was determined by PCR. The binding of 5 and 6 to the progesterone receptor (PR) was also evaluated. RESULTS: Treatments with T, LNG, T+LNG, P, T+P, 5, T+5, T+6, P, P+5 and P+6 increased the mRNA expression for glycerol 3-phosphate acyl transferase (GPAT), ß-hydroxy-ß-methylglutaryl-CoA synthase (HMG-CoA-S), ß-hydroxy-ß-methylglutaryl-CoA reductase (HMG-CoA-R), phosphatidylinositol synthase as compared to the controls. However, squalene synthase was increased with all treatments except with T+5 and 6; 6 did not significantly increase the expression for GPAT or HMG-CoA-S, however it increased the concentration of HMG-CoA-R enzyme. 5 and 6 bind to the PR, thus indicating that the effect of these steroids on the mRNA expression could be the result of their binding. CONCLUSION: The lipid metabolism is regulated by several steroids thought different mechanism of action, in flank organs.

Molecular interactions of levonorgestrel and its 5 alpha-reduced derivative with androgen receptors in hamster flanking organs.

The 5 alpha-reduction of levonorgestrel (LNG) as well as its binding capacity to the androgen receptors of the hamster flank organ were investigated. Furthermore, the effects of LNG and its 5 alpha-reduced metabolite in the flank organ test and on [U-14C]glucose incorporation into lipids by this tissue were determined. Homogenates from female hamster flank organs were incubated in the presence of [3H]LNG at pH 7.4. The radioactive 5 alpha-LNG metabolite was isolated and its purity was assessed. Competition experiments for androgen binding receptors were carried out with 1.38 nM [3H-7 alpha-17 alpha]dimethyl-19- nortestosterone (DMNT), Kd, plus a range of increasing concentrations of the different unlabeled steroid hormones. The flank organ test was performed in vivo, and [U-14C]glucose incorporation into lipids was determined under organ culture conditions. The 5 alpha-LNG had the same binding capacity to androgen receptors (AR) as LNG in male flank organs. The flank organ test demonstrated that 5 alpha-LNG activity was similar to that observed for levonorgestrel and testosterone (T) on gonadectomized male hamster flank organs. Topical applications of LNG or 5 alpha-LNG increased [U-14C]glucose incorporation into lipids in a way similar to that of T. The overall data indicate that LNG and 5 alpha-LNG produced androgenic activity in the lipid pathway of male flank organs, and that 5 alpha-reduction is not essential for the LNG effect on this tissue.

Evaluation of levonorgestrel action on the flank organ and the sebaceous gland lipogenesis of female hamsters.

The role of testosterone and levonorgestrel action on the flank organ by measuring sebaceous gland lipogenesis of female hamsters by the metabolic incorporation of 14C-glucose were investigated. Also, a partial characterization of the radiolabeled lipid fraction was obtained. The effects of in vivo steroids administration were evaluated by 14C-U-glucose metabolic incorporation into lipids by the female hamster flank organs in culture conditions, in the presence or absence of LNG and/or T in the incubation medium. The radioactive lipids were identified by thin layer chromatography. Levonorgestrel alone or together with testosterone on female hamster flank organs decreased the organ weight and sebum content compared with T-treatment alone. In culture conditions, a rapid and significant increase of radiolabeled glucose was observed with T. By contrast when LNG was present in the incubation medium, no differences in 14C-U-glucose incorporation were observed when compared with their controls. When T+LNG were added, a similar result to the obtained when using LNG alone was determined. Testosterone increased glycerides and free fatty acids but decreased polar lipids; whereas LNG did not have any effect in the relative proportions of 14C-U-glucose incorporated into the different classes of lipids, when it was compared with their controls. The results indicated that LNG abolished the increasing effect of 14C glucose incorporation caused by T and changed the lipid composition induced on female hamsters flank organs.