PurposeTo investigate the permeation of model drug,propranolol hydrochloride, through the excised porcine buccal mucosa. To study the influences of various factors on the buccal absorption also studied. MethodsUsing excised porcine buccal mucosa permeation test in vitro. By means of changing the medium pH, osmotic concentration, drug concentration, the concentration of various penetration enhancers including sodium glycodeoxycholate (GDC), sodium glycocholate (GC), dimethy1-β-cyclodextrin (DMβCD), and hydropropyl-β-cyclodextrin(HPβCD). The permeation rates and permeability coefficients(P) were determined and evaluated. The solubilities and apparent partition coefficients also determined in some tests. ResultsThe result showed that the P were increased when porcine buccal mucosae were pretreated with every penetration enhancement of certain concentration, increased as the pH of test solution rose from 4.9 to 9.1. The P remained constant as the concentration of propranolol hydrochloride increased from 5 to 80 mg/ml, decreased with the increasing of osmotic concentration Conclusions The absorption of propranolol hydrochloride through porcine buccal mucosa is a typical passive process, and affected by penetration enhancers, medium pH, osmotic concentration.

Objective To investigate the changes in cathepsin B (CatB) expression in acutely photodamaged human dermal fibroblasts (HDFs) and their significance.Methods HDFs were isolated from the foreskin of children,and subjected to primary culture and subculture.The fourth-to eighth-passage HDFs were used in the following experiment.HDFs were divided into two groups to receive irradiation with different doses of ultraviolet A (UVA) for different durations (acutely photodamaged group) or remain unirradiated (control group).Cell counting kit-8 (CCK8) assay was conducted to evaluate the proliferative activity of HDFs after irradiation with UVA at 5,10,15,20 and 25 J/cm2 respectively.Western blot and quantitative real-time reverse transcription PCR were performed to measure the protein and mRNA expressions of CatB respectively in HDFs at 24,48 and 72 hours after exposure to UVA at 10 J/cm2,and at 48 hours after exposure to UVA at 10,15,20 and 25 J/cm2.Statistical analysis was carried out by analysis of variance and least significant difference (LSD) test using the SPSS 13.0 software.Results UVA radiation induced a decrease in the proliferative activity of HDFs.When the dose of UVA was ≤ 10 J/cm2,the survival rate of HDFs maintained higher than 85％,and significant differences were observed in cell survival rate between unirradiated and irradiated HDFs at 24,48 and 72 hours (all P ＜ 0.05).Western blot showed that the gray value of CatB protein in the acutely photodamaged group irradiated with 10 J/cm2 UVA was significantly higher than that in the control group at 24 hours (0.76 ± 0.14 vs.0.35 ± 0.01,P ＜ 0.05),48 hours (1.34 ± 0.38 vs.0.45 ± 0.12,P＜ 0.05) and 72 hours (0.82 ± 0.09 vs.0.61 ± 0.06,P＜ 0.05).Increased mRNA expressions of CatB were also observed in the acutely photodamaged group compared with the control group at 24 hours (0.149 ± 0.009 vs.0.089 ± 0.015,P ＜ 0.05),48 hous (0.173 ± 0.009 vs.0.091 ± 0.010,P ＜ 0.05) and 72 hours (0.185 ± 0.158 vs.0.111 ± 0.017,P ＜ 0.05) after UVA radiation at 10 J/cm2.The gray value of CatB protein was 0.99 ± 0.07,1.49 ± 0.14,1.89 ± 0.08,2.07 ± 0.06 in HDFs at 48 hours after exposure to UVA of 10,15,20 and 25 J/cm2,respectively,significantly higher than that in the control group (0.60 ± 0.05,all P ＜ 0.05).Similarly,the mRNA expression of CatB was up-regulated in HDFs at 48 hours after UVA radiation at 10,15,20 and 25 J/cm2 compared with the unirradiated HDFs.Conclusion The protein and mRNA expressions of CatB are up-regulated in acutely photodamaged HDFs induced by UVA radiation.

Objective To investigate the effects of advanced glycation end products(AGE)on the expressions and activity of cathepsin D(CatD)in ultraviolet A(UVA)?irradiated human dermal fibroblasts. Methods Human dermal fibroblasts were isolated and harvested from the circumcised foreskin of children, and subjected to a primary culture. CCK?8 assay was performed to screen non?cytotoxic concentrations of AGE?bovine serum albumin (BSA). Some fibroblasts were incubated with 50, 100 and 300 mg/L AGE?BSA separately for 24 hours, with untreated cells as the control group. Then, reverse transcription(RT)?PCR, Western?blot analysis and a fluorimetric assay were performed to measure the mRNA and protein expressions as well as activity of CatD, respectively. Some fibroblasts were classified into six groups: control group receiving no treatment, AGE?BSA group and BSA group treated with the highest non?cytotoxic concentration of AGE?BSA and the same concentration of BSA respectively for 24 hours, UVA group irradiated by 10 J/cm2 UVA, UVA?AGE?BSA group and UVA?BSA group treated with AGE?BSA and BSA at the above non?cytotoxic concentration respectively for 24 hours both before and after UVA radiation at 10 J/cm2. After the treatments, RT?PCR, Western?blot analysis and a fluorimetric assay were conducted to detect mRNA and protein expressions and activity of CatD respectively. Results AGE?BSA of 50- 200 mg/L exhibited no obvious influence on cellular proliferation of fibroblasts. The fibroblasts incubated with AGE?BSA of 50, 100 and 200 mg/L showed a significant increase in the mRNA expression(0.267 ± 0.007, 0.348 ± 0.007, and 0.418 ± 0.006 respectively), protein expression (1.403 ± 0.181, 2.233 ± 0.090 and 2.477 ± 0.111 respectively), and activity(1.760 ± 0.080, 2.330 ± 0.060 and 2.890 ± 0.080 respectively)of CatD compared with the control group(mRNA:0.161 ± 0.006;protein:0.903 ± 0.200;activity:1.100 ± 0.090, all P < 0.05). AGE?BSA increased CatD expressions and activity in a dose?dependent manner. The mRNA and protein expressions as well as activity of CatD were significantly higher in the UVA group than in the control group (mRNA expression: 0.480 ± 0.005 vs. 0.155 ± 0.005; protein expression: 2.583 ± 0.199 vs. 0.920 ± 0.235;activity:2.970 ± 0.110 vs. 1.110 ± 0.040, all P<0.05), but significantly lower in the UVA?AGE?BSA group than in the UVA group(mRNA expression:0.394 ± 0.008 vs. 0.480 ± 0.005;protein expression:2.070 ± 0.125 vs. 2.583 ± 0.199;activity: 2.560 ± 0.060 vs. 2.970 ± 0.110, all P < 0.05). Conclusion AGEs could increase CatD expressions and activity in human dermal fibroblasts not receiving UVA irradiation, but inhibit their increase in UVA?induced human dermal fibroblasts.

Objective To evaluate the performance of transfection with a complex plasmid encoding green fluorescent protein tagged CatD (GFP-CatD)in researches on chronic photodamaged fibroblasts. Methods Human dermal fibroblasts (HSFs)were irradiated with ultraviolet A (UVA)at 25 J/cm2 once a day for 21 consecutive days to establish a chronic photodamaged cell model. A plasmid encoding GFP-CatD was constructed and transfected into some chronic photodamaged fibroblasts (experimental group). The photodamaged HSFs receiving no treatment served as the blank control group, and those transfected with the negative plasmid encoding GFP only as the negative control group. After additional culture, fluorescence microscopy and Western-blot analysis were performed to observe and measure the expression of GFP-CatD in HSFs respectively, flow cytometry and methyl thiazolyl tetrazolium (MTT)assay to evaluate the apoptosis and proliferation of chronic photodamaged fibroblasts respectively. Results Fluorescence microscopy showed the expression of GFP-CatD in cytoplasm of chronic photodamaged fibroblasts at 96 hours after transfection with the GFP-CatD-encoding plasmid. Western-blot analysis revealed that the expression of CatD in the experimental group was 1.28 times that in the blank control group. There were no significant differences in the apoptosis rate(4.29% ± 1.30%vs. 3.03% ± 1.70% , P > 0.05)or proliferative rate (45.20% ± 4.70% vs. 43.60 ± 3.90% , P > 0.05)between the experimental group and blank control group. Conclusion CatD could be traced in chronic photodamaged fibroblasts with no changes in biological activity or cell cycle after transfection with the GFP-CatD-encoding complex plasmid.

Objective To investigate the effect of ultraviolet A (UVA) radiation on the expression and secretion of cathepsin G (CatG) by human dermal fibroblasts.Methods Dermal fibroblasts were isolated from the foreskins of boys,and subjected to primary culture and subculture.After 10 or less passages,the fibroblasts were collected and divided into several groups to be irradiated with 10 J/cm2 UVA followed by 24,48 and 72 hours of additional culture,or be irradiated with 10,20 and 30 J/cm2 UVA followed by 24 hours of additional culture,with those receiving no treatment serving as the control group.Subsequently,cells and culture supernatant were collected,real time PCR and Western blot were performed to detect the expressions of CatG mRNA and protein respectively in these cells,and enzyme-linked immunosorbent assay (ELISA) was conducted to measure the expression of CatG protein in the culture supernatant of these cells.Results Compared with the control group,the fibroblasts irradiated with 10 J/cm2 UVA showed a significant increase at 24,48 and 72 hours in the expressions of CatG mRNA (0.376 ± 0.014 vs.0.183 ± 0.003,0.308 ± 0.022 vs.0.185 ± 0.005,0.296 ± 0.032 vs.0.182 ± 0.004,respectively,all P＜ 0.05) and protein (1.80 ± 0.12 vs.0.96 ± 0.06,1.41 ± 0.17 vs.0.95 ± 0.22,1.27 ± 0.09 vs.1.00 ± 0.14,respectively,all P ＜ 0.05),as well as in the supernatant level of CatG protein ((161.35 ± 7.55) vs.(122.45 ± 6.46) ng/L,(141.76 ± 2.95) vs.(124.17 ± 6.15) ng/L,(139.63 ± 3.04) vs.(121.72 ± 3.17) ng/L respectively,all P ＜0.05),with the strongest increase observed at 24 hours.At 24 hours after 10,20 and 30 J/cm2 of UVA radiation,the expression of CatG mRNA in irradiated fibroblasts was 1.90,2.51 and 3.04 times respectively (all P ＜ 0.05),the expression of CatG protein was 1.88,3.97 and 4.72 times respectively (P ＜ 0.05),and the supernatant level of CatG protein was 1.36,1.50 and 1.66 times respectively (P ＜ 0.05),that in the control group,and there was an increasing trend in all the above three parameters with increasing dose of UVA.Conclusion Acute UVA radiation can promote the expression and secretion of CatG by human dermal fibroblasts.

Objective To investigate the effects of repetitive ultraviolet A(UVA) radiation on the endocytosis and intracellular degradation of extracellular elastin by human dermal fibroblasts(HDFs), and to explore the mechanism responsible for elastin accumulation in photoaging skin. Methods Cultured HDFs were divided into two groups:repetitive UVA radiation group treated with UVA radiation(9.9 J/cm2)once a day for seven consecutive days to establish a chronic photodamage model, and blank control group receiving no treatment. For the verification of the model, flow cytometry was performed to detect cell cycle, and senescence-associated β-galactosidase staining to determine the degree of cell senescence. Fluorescent tracer technique and conjugated polymer-based fluorescence quenching technique were conducted to observe the endocytosis and intracellular degradation of extracellular elastin in culture media by HDFs in these groups. Results Compared with the blank control group, the repetitive UVA radiation group showed increased proportions of G1-phase cells and senescent cells, which confirmed the successful establishment of chronic photodamage model in the repetitive UVA radiation group. After coculture with elastin for 24, 48 and 72 hours, the endocytosis rate of elastin was 10.0% ± 1.4%, 27.8% ± 4.2% and 39.9% ± 4.1% respectively in the blank control group, 9.9% ± 1.6%, 28.3% ± 5.1% and 42.0% ± 5.7% respectively in the repetitive UVA radiation group, with no significant difference between the two groups at the three time points (all P > 0.05). The percentage of cells showing intracellular degradation of extracellular elastin was significantly lower in the repetitive UVA radiation group than in the blank control group (4.2% ± 1.1% vs. 7.7% ± 0.9% at 24 hours, 16.5% ± 2.4% vs. 22.8% ± 1.8% at 48 hours, 26.7% ± 2.6% vs. 33.9% ± 3.1% at 72 hours, all P < 0.05). Conclusions UVA radiation at 9.9 J/cm2 for 7 consecutive days can decrease the intracellular degradation of extracellular elastin by HDFs, but has no obvious effect on endocytosis of elastin.

Objective To observe the expression changes of cathepsin K (CatK) in human dermal fibroblasts at different time points after different doses of ultraviolet A (UVA) irradiation.Methods Dermal fibroblasts were isolated from circumcised foreskins of children,and subjected to primary culture and subculture.Cells at third-tenth passage were used in the following experiment.Some fibroblasts were irradiated with UVA of 10 J/cm2 and collected at 24,48 and 72 hours separately after the irradiation,and some fibroblasts were irradiated with UVA of 10,20 and 30 J/cm2 separately and harvested 48 hours later.The fibroblasts receiving no irradiation served as the control group.Reverse transcription PCR and Western blot were carried out to detect the mRNA and protein expressions of CatK in fibroblasts,respectively.Results Compared with the control fibroblasts,those irradiated with UVA of 10 J/cm2 showed a significant elevation in the mRNA and protein expression levels of CatK on day 1 (0.351 ± 0.038 vs.0.177 ± 0.006,1.76 ± 0.27 vs.0.82 ± 0.45,respectively,both P＜ 0.05),day 2 (0.510 ± 0.017 vs.0.176 ± 0.002,2.97 ± 0.36 vs.1.58 ± 0.15,respectively,both P＜ 0.05) and day 3 (0.313 ± 0.012 vs.0.173 ± 0.002,2.23 ± 0.14 vs.1.29 ± 0.32,respectively,both P ＜ 0.05),with the highest expressions of CatK mRNA and protein observed on day 2.Within the range of 10-30 J/cm2,UVA enhanced the CatK mRNA and protein expression levels in a dose-dependent manner.In detail,at 48 hours after the irradiation with UVA of 10,20 and 30 J/cm2,the CatK mRNA expression level in the irradiated fibroblasts was 2.34,2.91 and 3.18 times,and the CatK protein expression level 1.77,2.82 and 3.64 times,respectively,that in the control fibroblasts (all P ＜ 0.05).Conclusion The expression of CatK is up-regulated in human dermal fibroblasts after UVA irradiation.

Objective To investigate whether ultraviolet A UVA)-induced CatK expression is regulated by the mitogen-activated protein kinases (MAPK) signaling pathway in human dermal fibroblasts in vitro.Methods Human dermal fibroblasts were obtained from circumcised foreskin of children,and subjected to primary culture.After several passages of subculture,some fibroblasts were irradiated with UVA at a dose of 10 J/cm2.Western blot was performed to measure the expressions of total and phosphorylated JNK (t-and p-JNK) and P38 (t-and p-P38) at 0.75,1.5,3 and 6 hours after the irradiation.Some fibroblasts were divided into six groups:control group receiving no treatment,SP group treated with SP600125 of 800 nmol/L,SB group treated with SB203580 of 10 μmol/L,UVA group irradiated with UVA at a dose of 10 J/cm2,UVA-SP group treated with SP600125 for 1 hour before and for 1.5 or 48 hours after UVA irradiation at 10 J/cm2,UVA-SB group treated with SB203580 for 1 hour before and for 1.5 or 48 hours after UVA radiation at 10 J/cm2.Subsequently,Western blot was performed to determine the expressions of p-c-Jun and p-MAPKAPK2 in these groups at 1.5 hours after the UVA irradiation,and reverse transcription (RT)-PCR and Western blot to detect the mRNA and protein expressions of CatK at 48 hours after the UVA irradiation,respectively.Statistical analysis was carried out by t test,one way analysis of variance and least significant difference (LSD)-t test.Results The expression levels (gray values) of p-JNK and p-P38 were significantly increased at 0.75 hour (4.77 ± 0.19 and 2.44 ± 0.13 respectively,both P ＜ 0.05) and 1.5 hours (4.68 ± 0.09 and 2.30 ± 0.04 respectively,both P ＜ 0.05),but showed no significant changes at 3 hours (both P ＞ 0.05) and 6 hours (both P ＞ 0.05) after the UVA irradiation compared with those before the irradiation (3.2 ± 0.27 and 1.61 ± 0.08 respectively).A significant decrease was observed in the expression of p-c-Jun in the UVA-SP group and p-MAPKAPK2 in the UVA-SB group compared with the UVA group (p-c-Jun,2.55 ± 0.48 vs.4.85 ±0.96; p-MAPKAPK2,1.16 ± 0.12 vs.2.46 ± 0.09,both P ＜ 0.05).The CatK mRNA and protein expressions were attenuated by 61.1％ and 44.3％ respectively in the UVA-SP group (both P ＜ 0.05),and by 71.3％ and 50.4％ respectively in the UVA-SB group (both P ＜ 0.05) in comparison with the UVA group.The UVA-SP group also showed a significant reduction in CatK mRNA and protein expressions as compared with the UVA-SB group (both P ＜ 0.05).Conclusion Both JNK and P38 signaling pathways,especially the JNK pathway,may contribute to the upregulation of CatK expression in dermal fibroblasts induced by UVA irradiation.

EBSS (epidermolysis bullosa simplex superficialis) is mainly caused by gene mutations which targeted protein as plakophilin-1, desmoplakin and keratins. 1p36 gene deleted could cause typical clinical manifestations and might also affect the expression of functional genes in other regions. Here we reported the first case of PKP1 gene and DSP gene mutation coexisted with 1p36 deletion presented as serious EBSS and 1p36 deletion syndromes and identified a new homozygous mutation in the PKP1 gene (chr1:201292246 c.1672 T＞C) and in the DSP gene (chr6:7580346 c.3923C＞T).

EBSS (epidermolysis bullosa simplex superficialis) is mainly caused by gene mutations which targeted protein as plakophilin-1, desmoplakin and keratins. 1p36 gene deleted could cause typical clinical manifestations and might also affect the expression of functional genes in other regions. Here we reported the first case of PKP1 gene and DSP gene mutation coexisted with 1p36 deletion presented as serious EBSS and 1p36 deletion syndromes and identified a new homozygous mutation in the PKP1 gene (chr1:201292246 c.1672 T＞C) and in the DSP gene (chr6:7580346 c.3923C＞T).