BACKGROUND: To observe the effect of linear alkylbenzenesulfonate (LAS) on oxidative stress and collagen fiber in skin tissue of mice and to explore the correlation between oxidative stress and collagen metabolism.
 METHODS: Forty healthy Kunming mice (male) were randomly divided into 4 groups: a control group, a low-, middle- and high-dose group of LAS (LD, MD and HD groups), treated with LAS at 150, 300 and 600 mg/L respectively (n=10 per group). The skin on the back of mice was smeared with distilled water or different dosage of LAS for 60 days. The measured indexes included general condition of mice, HE and Masson staining of skin, the content of hydroxyproline (Hyp) in skin tissue, the activity of super oxidase dismutase (SOD) and the content of malondialdehyde (MDA) in skin tissue and serum, and the activity of lactate dehydrogenase (LDH) in serum.
 RESULTS: Compared with the control group, the changes of diet, daily activities and mental state of mice with different dose of LAS were not obvious during the experiment, but the body weight of mice in the experimental groups reduced obviously after 4 weeks of experiment (P<0.01), and their skin tissue was thinner, some of epidermis of skin contained areas with cellular necrosis and abscission. Superficial layer of dermis was infiltrated by inflammatory cells. The collagen fibers were looser and dimmer. At the same time, the content of MDA and the activity of LDH increased remarkably (P<0.01), while the activity of SOD and the content of Hyp decreased obviously (P<0.01).
 CONCLUSIONS LAS can induce oxidative stress in the skin tissue of mice, which can destroy the integrity of skin structure and collagen fiber and reduce the content of collagen fiber. The oxidative damage might be the primary cause for disorders of collagen fiber.
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Alkanesulfonic Acids ; pharmacology ; Animals ; Collagen ; metabolism ; Male ; Malondialdehyde ; metabolism ; Mice ; Oxidative Stress ; Skin ; drug effects ; metabolism

BACKGROUND: Melanin is detectable in various sense organs including the skin in animals. It has been reported that melanin adsorbs toxic elements such as mercury, cadmium, and lead. In this study, we investigated the adsorption of molybdenum, which is widely recognized as a toxic element, by melanin. METHODS: Molybdenum level of the mouse skin was measured by inductively coupled plasma mass spectrometry. The pigmentation level of murine skin was digitalized as the L* value by using a reflectance spectrophotometer. An in vitro adsorption assay was performed to confirm the interaction between molybdenum and melanin. RESULTS: Our analysis of hairless mice with different levels of skin pigmentation showed that the level of molybdenum increased with an increase in the level of skin pigmentation (L* value). Moreover, our analysis by Spearman's correlation coefficient test showed a strong correlation (r = - 0.9441, p < 0.0001) between L* value and molybdenum level. Our cell-free experiment using the Langmuir isotherm provided evidence for the adsorption of molybdenum by melanin. The maximum adsorption capacity of 1 mg of synthetic melanin for molybdenum was 131 μg in theory. CONCLUSION Our in vivo and in vitro results showed a new aspect of melanin as an adsorbent of molybdenum.
Adsorption ; Animals ; Melanins ; chemistry ; metabolism ; Mice ; Mice, Hairless ; Mice, Transgenic ; Molybdenum ; chemistry ; metabolism ; pharmacology ; Skin ; chemistry ; drug effects ; Skin Pigmentation ; drug effects ; Water Pollutants, Chemical ; chemistry ; metabolism ; pharmacology

OBJECTIVETo explore the biomarkers for monitoring trinitrotoluene (TNT) exposure, the relationship between TNT hemoglobin adducts and TNT exposed level.

METHODHemoglobin adducts (4A-Hb and 2A-Hb) were determined by GC-MS in 25 TNT exposed workers. TNT exposed level was evaluated by determining skin contaminated and inhaled TNT levels. The correlation between hemoglobin adducts level and TNT exposed level was analyzed.

RESULTSThere was a correlation between total TNT exposure level, especially skin exposure level, and 4A-Hb or 2A-Hb content. No significant difference was found between the slopes and intercepts of lin ear equation of (4A-Hb) vs TNT exposed level and linear equation of (4A-Hb +2A-Hb) vs TNT exposed level (P > 0.05).

CONCLUSIONSkin contamination is the major role of TNT exposure. TNT exposed level can be evaluated by determining the content of both 4A-Hb and 2A-Hb, and 4A-Hb is more suitable for monitoring TNT exposure.

Environmental Monitoring ; methods ; Hemoglobins ; metabolism ; Humans ; Occupational Exposure ; Skin ; drug effects ; Trinitrotoluene ; metabolism

OBJECTIVETo investigate the role of protein kinase C (PKC) in the down-regulation of fibroblast proliferation in normal skin (NFb) and hyperplastic scar (SFb) by adrenaline.

METHODSHuman NFb and SFb cells were cultured in vitro. Phentolamine (in final concentrations of 0 and 3 x 10(-6) micromol/L) was added to the culture medium. One hour later, adrenaline in different final concentrations (0.00, 0.05, 0.10, 0.20 micromol/L) was added to the culture medium and incubated for 24 hours. The cellular proliferation activity and cell viability rate were determined with MTT. The cell culture supernatant was harvested for the determination of LDH activity to assess the toxicity of phentolamine and adrenaline. The phosph-PKC activity was determined with Western-blotting and was semiquantitatively analyzed.

RESULTS(1) After stimulation with adrenaline alone, or combined 0.20 micromol/L adrenaline with 3 x 10(-6) micromol/L phentolamine, the cell viability of both NFb and SFb decreased significantly (P < 0.05 or 0.01). (2) There was no difference in the LDH activity between the cells either stimulated by adrenaline in all concentrations or by combination of adrenaline and phentolamine (P > 0.05). (3) The phosphorylation of PKC in NFb and SFb cells stimulated by 0.05, 0.10, 0.20 micromol/L adrenaline was obviously higher than that before stimulation (P < 0.01). When phentolamine in the concentration of 3 x 10(-6) micromol/L was used alone for stimulation, the phosphorylation of PKC in NFb cells (123 +/- 5) was also evidently higher than that before stimulation (80 +/- 5, P < 0.01). But there was no such effect on SFb cells (P > 0.05). When adrenaline in the concentration of 0.05, 0.10 or 0.20 micromol/L was separately added together with phentolamine in the dose of 3 x 10(6) micromol/L for the stimulation, the phosphorylation of PKC in NFb and SFb cells was evidently lower than that when 3 different concentrations of adrenaline was used alone for stimulation (P < 0.01).

CONCLUSIONAdrenaline can inhibit the proliferation of NFb and SFb by activating PKC through binding alpha adrenaline receptor.

Cell Proliferation ; drug effects ; Cells, Cultured ; Cicatrix, Hypertrophic ; metabolism ; Down-Regulation ; Epinephrine ; adverse effects ; Fibroblasts ; cytology ; Humans ; Phentolamine ; adverse effects ; Phosphorylation ; Protein Kinase C ; metabolism ; Skin ; drug effects

OBJECTIVETo study the changes of serum complement C and immunoglobulin (Ig) in sensitized guinea pigs exposed to trichloroethylene.

METHODSThirty six white female guinea pigs (250 ∼ 300 g) were randomly divided into blank control group (5 guinea pig), solvent (olive oil) control group (5 guinea pig) and TCE treatment group (26 guinea pig). According to guinea pig maximization test (GPMT), guinea pigs were exposed to TCE. After stimulating contact for 24 h, the skin reactions of guinea pig back test area were recorded and scored. According to Skin sensitization integral, the guinea pigs treated with TCE were divided into the sensitized group (score ≥ 1) and un-sensitized group (score 0). The concentrations of serum C3, C4, IgA, IgG and IgM were detected in 24 and 72 h, respectively after the experiment.

RESULTSThe sensitization rates of group treated by TCE was 65.38%. The serum C3 levels of groups sensitized to TCE for 24 and 73h were 99.75 ± 1.45 and 93.28 ± 3.61g/ml, respectively, which were significantly lower than that (112.30 ± 9.10 g/ml) of solvent control group (P < 0.05). Also The serum C4 levels of groups sensitized to TCE for 24 and 73 h were 34.63 ± 2.53 and 33.82 ± 2.76g/ml, respectively, which were significantly lower than that (43.87 ± 3.65 g/ml) of solvent control group (P < 0.05). The serum IgA and IgM levels of groups sensitized to TCE and unsensitized to TCE for 24 and 72 h were significantly lower than those of solvent group (P < 0.05). as compared with unsensitized groups, the serum IgA levels of the groups sensitized to TCE for 24 and 72 h significantly decreased (P < 0.05).

CONCLUSIONAfter the guinea pig skin was sensitized to TCE, the serum C3, C4 levels decreased, the immune function disordered.

Animals ; Complement System Proteins ; metabolism ; Female ; Guinea Pigs ; Immunity, Humoral ; drug effects ; Immunoglobulins ; blood ; Skin ; drug effects ; Trichloroethylene ; toxicity

Badu Shengji San(BDSJS) is a traditional Chinese medicine (TCM) used for drawing out toxin, eliminating suppuration and promoting granulation. Toxic minerals such as arsenic and lead are the two most important components of BDSJS. Previous hypothesis indicated that according to the compatibility theory of TCM, the toxicity of the entire BDSJS was weaker than that of arsenic and lead, respectively. In the present study, SD rats with injured skin were treated with distilled water and different composition of BDSJS (complete formulations, compatible herbs, mineral medicine containing arsenic and lead, mineral medicine containing arsenic and mineral medicine containing lead) once a day for consecutive 2 weeks. Kidney coefficient and urinary beta-N-acetyl glucosidase (NAG) were used as the indicators of renal toxicity and the content of malondiadehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), glutathione (GSH) and metallothionein (MT) in the renal tissue were measured. Our data showed that kidney coefficient, the severity of renal pathological lesion and MT level in the kidney of the entire BDSJS group decreased significantly compared with arsenic and lead group. Additionally, the NAG content of the entire BDSJS group had the decreased trend. The kidney CuZn-SOD level of the entire BDSJS group had the increased trend, but the MDA, GSH-PX, GSH level had no obvious difference. Our results suggested that compatible herbs in BDSJS relieved renal injury induced by arsenic and lead, and the attenuation mechanism may be related to MT and CuZn-SOD, but not to MDA, GSH-PX and GSH directly.
Animals ; Arsenic ; toxicity ; Body Weight ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; toxicity ; Glutathione ; metabolism ; Glutathione Peroxidase ; metabolism ; Kidney ; drug effects ; metabolism ; pathology ; Lead ; toxicity ; Male ; Malondialdehyde ; metabolism ; Metallothionein ; metabolism ; Rats ; Rats, Sprague-Dawley ; Skin ; drug effects ; Superoxide Dismutase ; metabolism

OBJECTIVETo investigate the effects of different kinds and concentration of transdermal enhancers on Lappaconitine transcutaneous permeation when used individually or together.

METHODUsing modified Franz-type diffusion cell and excised human body skin as an in vitro transdermal model, the concentration of lappaconitine was determined by HPLC, then cumulative permeation quantity (Q) and stability rate (J) of progesterone were calculated.

RESULTPenetration enhancers such as propylene glycol, dodecanol, IPM, and particularly 3% OA and Azone, can significantly enhance the penetration rate of lappaconitine. Concentration effect of penetration enhancers concentration on lappaconitine transcutaneous permeation were found in experiments, the permeation effect of Azone was better than Azone + OA and Azone + propylene glycol.

CONCLUSIONThe transdermal rate of lappaconitine from batch which contains 3% OA or Azone is higher than others. Combination of Azone with other penetration enhancers is not recommended for Lappaconitine transcutaneous permeation.

Aconitine ; analogs & derivatives ; metabolism ; Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal ; metabolism ; Humans ; Permeability ; drug effects ; Skin ; cytology ; metabolism

A visible cutaneous scar develops from the excess formation of immature collagen in response to an inflammatory reaction. This study examined the role of epidermal growth factor (EGF) in the formation of cutaneous scars. Twenty Crl:CD-1 (ICR) mice were used and 2 full-thickness skin wounds were made on the dorsum of each mouse. One of the wounds was treated with recombinant human EGF by local application and the other was treated with saline for control until complete healing was achieved. The EGF-treated group's wounds healed faster than the control group's. The width of the scar was smaller by 30% and the area was smaller by 26% in the EGF-treated group. Inflammatory cell numbers were significantly lower in the EGF-treated group. The expression of transforming growth factor (TGF)-beta1 in the EGF-treated group was increased. It was observed that the amount of collagen in the EGF-treated group was larger than the control group. In the EGF-treated group, the visible external scars were less noticeable than that in the control group. These results suggest that EGF can reduce cutaneous scars by suppressing inflammatory reactions, decreasing expression of TGF-beta1, and mediating the formation of collagen.
Animals ; Cicatrix/pathology/*prevention & control ; Collagen/metabolism ; Epidermal Growth Factor/*pharmacology ; Humans ; Inflammation/metabolism ; Mice ; Recombinant Proteins/*pharmacology ; Skin/drug effects/metabolism/pathology ; Wound Healing/*drug effects

OBJECTIVETo explore the effect of tacrolimus on murine hair follicle cycle.

METHODHematoxylin-eosin dyeing and reverse transcription-polymerase chain raction techniques were used.

RESULTSFive days after depilation, the hair follicles in both the tacrolimus group and the minoxidil group was in anagen V, while that in the vaseline group was in anagen III. vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were detected in back skin in both the tacrolimus group and the minoxidil group, but not in the vaseline group.

CONCLUSIONTacrolimus can promote the growth of hair by stimulating the hair follicle to enter anagen V in mice, which may be explained by the effects of VEGF and HGF.

Animals ; Hair Follicle ; drug effects ; physiology ; Hepatocyte Growth Factor ; metabolism ; Mice ; Mice, Inbred C57BL ; Minoxidil ; pharmacology ; Skin ; drug effects ; metabolism ; Tacrolimus ; pharmacology ; Vascular Endothelial Growth Factor A ; metabolism

OBJECTIVETo investigate the expression of apoptosis and caspase-8, cyt c in the skin of the BALB/c mice exposed to trichloroethylene (TCE).

METHODS30 BALB/c mice were divided in random into the solvent control group, 10% TCE group, 20% TCE group, 40% TCE group, 80% TCE group and 100% TCE group. Apoptotic cells were detected by TUNEL and EM. The expressions of caspase-8 and cyt c were detected with immunohistochemical method.

RESULTSEM showed that the apoptosis of cells was found in the high dosage groups. The immunohistochemical results showed that there were significant differences in the apoptosis rate and the activity of cyt c between the different dosage groups. There was the significant difference in the apoptosis rate between the 40%, 80%, 100% TCE groups the control group (P < 0.01). There was the significant difference in the expression of cyt c between the 20%, 40%, 80%, 100% TCE groups [(2.60 +/- 0.54), (3.42 +/- 0.56), (5.81 +/- 1.30) and (6.00 +/- 0.70), respectively] and the control group (P < 0.01). The expressions of caspase-8 had no significant differences (P > 0.05).

CONCLUSIONApoptosis plays an important role in trichloroethylene induced irritant injury in skin and the apoptosis may be related with the mitochondrial injury.

Animals ; Apoptosis ; drug effects ; Caspase 8 ; metabolism ; Cytochromes c ; metabolism ; Female ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Skin ; drug effects ; metabolism ; pathology ; Trichloroethylene ; toxicity