Objective To explore the expression characteristics of chaperone interacting protein (CHIP) in normal, scar and chronic ulcer tissues and its relationship with wound healing. Methods Twenty biopsies including scar tissues(n=8), chronic ulcer tissues(n=4) and normal tissues(n=8)were used in this study. The immunohistochemical staining (power visionTMtwo-step histostaining reagent) was used to explore the amount and expression characteristics of such protein.Results The positive expression of CHIP was observed in fibroblasts, endothelial cells and epidermal cells in dermis and epidermis. It was not seen ininflammatory cells. The expression amount of CHIP in scar tissues, chronic ulcer tissues and normal tissues was 89%, 83% and 17% respectively. Conclusion Although the function of CHIP is not fully understood at present, the fact that this protein is expressed only at the mitogenic cells indicates that it may be involved in mitogenic regulation during wound healing.
To investigate the inhibitory effect of Col I A1 antisense ol igodeoxyneucleotide (ASODN) transfection mediated by cationic l iposome on Col I A1 expression in human hypertrophic scar fibroblasts. Methods Scar tissue was obtained from volunteer donor. Human hypertrophic scar fibroblasts were cultured by tissue block method. The cells at passage 4 were seeded in a 6 well cell culture plate at 32.25 × 104 cells/well, and then divided into 4 groups: group A, l iposomeand Col I A1 ASODN; group B, Col I A1 ASODN; group C, l iposome; group D, blank control. At 8 hours, 1, 2, 3 and 4 days after transfection, total RNA of the cells were extracted, the expression level of Col I A1 mRNA was detected by RT-PCR, the Col I A1 protein in ECM was extracted by pepsin-digestion method, its concentration was detected by ELISA method. Results Agarose gel electrophoresis detection of ampl ified products showed clear bands without occurrence of indistinct band, obvious primer dimmer and tailing phenomenon. Relative expression level of Col I A1 mRNA: at 8 hours after transfection, group A was less than groups B, C and D (P lt; 0.05), and groups B and C were less than group D (P lt; 0.05), and no significant difference was evident between group B and group C (Pgt; 0.05); at 1 day after transfection, groups A and B were less than groups C and D (P lt; 0.05), and there was no significant difference between group A and group B, and between group C and group D (P gt; 0.05 ); at 2 days after transfection, there were significant differences among four groups (P lt; 0.05); at 3 and 4 days after transfection, group A was less than groups B, C and D (P lt; 0.05), group B was less than groups C and D (P lt; 0.05), and no significant difference was evident between group C and group D (P gt; 0.05). Concentration of Col I protein: at 8 hours after transfection, group A was less than groups B, C and D (P lt; 0.05), groups B and C were less than group D (P lt; 0.05), and no significant difference was evident between group B and group C (P gt; 0.05); at 1 day after transfection, significant differences were evident among four groups (P lt; 0.05); at 2, 3 and 4 days after tranfection, groups A and B were less than groups C and D (P lt; 0.05), and no significant difference was evident between group A and group B (P gt; 0.05). Conclusion Col I A1 ASODN can inhibit mRNA and protein expression level of Col I A1. Cationic l iposome, as the carrier, can enhance the inhibition by facil itating the entry of ASODN into cells and introducing ASODN into cell nucleus.
Objective To investigate the effects of asiaticoside onthe proliferation and the Smad signal pathway of the hypertrophic scar fibroblasts.Methods The hypertrophic scar fibroblasts were cultured with tissue culture method. The expressions of Smad2 and Smad7 mRNA after asiaticoside treatment were determined by reverse transcriptionpolymerase chain reaction 48 hours later. Thecell cycle, the cell proliferation, the cell apoptosis and the expression of phosphorylated Smad2 and Smad7 with(experimental group) or without(control group) asiaticoside were detected with flow cytometry, immunocytochemistry and Western blot. Results Asiaticoside inhibited the hypertrophic scar fibroblasts from phase S to phase M. The Smad7 content and the expression of Smad7 mRNA were (1.33±1.26)% and (50.80±22.40)% in experimental group, and (9.15±3.36)% and (32.18±17.84)% in control group; there were significant differences between two groups (P＜0.05). While the content and the mRNA expression of Smad2 had no significant difference between two groups. Conclusion Asiaticoside inhibits the scar formation through Smad signal pathway.
The ultrastructures of 14 keloids and 7 hypertrophic scars were examined by electron micrascopy.Both lesions were found to be comprised of fibroblasts, macrophages, microfi brils of collagen andmicrovessels which were partly or completely obliterated. Most fibroblasts were of active cell types.They contained abundant coarse endoplasmic reticulum and prominent Golgi complexes. The fibrils inthe lesions were irtegularly arranged. Meanwhile myofibroblasts were often seen in the keloid.In the cytoplasm of the myofibroblasts, in addition to coarse endoplasmic reticulum and Golgi complexes, many fine myofilaments, dense bodies, dense patches and distrupted basal lamina were present. These characteristic features might help to differentiate keloid from hypertrophic sacr.
Objective To explore the change of gene expression of stress activated protein kinase (SAPK) and its upstream signalregulated molecule ——mitogen activated protein kinases(MAPKs) (MKK4 and MKK7) in hypertrophic scar and autocontrol normal skin. Methods The total RNA was isolated from 8 hypertrophic scars and 8 auto-control skin, and then mRNA was purified. The gene expressions of MKK4, MKK7 and SAPK were examined with reverse transcriptionpolymerase chain reaction(RT-PCR) method. Results In hypertrophic scar, both MKK7 and SAPK genes weakly expressed. In auto-control skin, the expression of these 2 genes was significantly elevated in comparison with hypertrophic scar (Plt;0.01). The expression levelsof these 2 genes were 1.5 times and 2.6 times as long as those of hypertrophic scar, respectively. Gene expression of MKK4 had no significant difference between autocontrol skin and hypertrophic scar (Pgt;0.05). Conclusion Decreased gene expression of MKK7 and SAPK which results in reducing cell apoptosis might be one of the mechanisms for controlling the formation of hypertrophic scar.
To determine the state of fibroblast during the process of development of hypertrophic scar (HS), 40 specimens of HS in different periods were collected. The expressions of prolifrating cell nuclear antigen (PCNA) and Ag-protein in nucleolar organizer regions (Ag NORs) as well as the content of total amino acids in the tissues were examined. The hypertrophic scar of 1st and 3rd month old, the expression of PCND and Ag NORs were the highest. In the 9th and 12th month old, althrough PCNA was nearly negative, but the expression of Ag NORs was low. The content of total amino acid was increased gradually as HS developed but the increase of amount of hydroxyproline was markedly slowed down in 9 month old HS. It was suggested that: (1) in the developing process of HS the proecess of overproliferation of fibroblasts was short and limitted in 1-3 months period in the process of wound lealing; (2) the synthesis of collagen was nearly stopped at 6 months, but that of other extracellular matrix such as fibronectin and proteoglycan might be continued to aggregate after 12 months.
Objective Col I A1 antisense oligodeoxyneucleotide (ASODN) has inhibitory effect on collagen synthesis in cultured human hypertrophic scar fibroblasts. To investigate the effects of intralesional injection of Col I A1 ASODN on collagen synthesis in human hypertrophic scar transplanted nude mouse model. Methods The animal model of humanhypertrophic scar transplantation was established in the 60 BALB/c-nunu nude mice (specific pathogen free grade, weighing about 20 g, and aged 6-8 weeks) by transplanting hypertrophic scar without epidermis donated by the patients into the interscapular subcutaneous region on the back, with 1 piece each mouse. Fifty-eight succeed models mice were randomly divided into 3 groups in accordance with the contents of injection. In group A (n=20): 5 μL Col I A1 ASODN (3 mmol/L), 3 μL l iposome, and 92 μL Opti-MEM I; in group B (n=20): 3 μL l iposome and 97 μL Opti-MEM I; in group C (n=18): only 100 μL Opti-MEM I. The injection was every day in the first 2 weeks and once every other day thereafter. The scar specimens were harvested at 2, 4, and 6 weeks after injection, respectively and the hardness of the scar tissue was measured. The collagens type I and III in the scar were observed under polarized l ight microscope after sirius red staining. The ultrastructures of the scar tissues were also observed under transmission electronic microscope (TEM). Additionally, the Col I A1 mRNAs expression was determined by RT-PCR and the concentrations of Col I A1 protein were measured with ELISA method. Results Seventeen mice died after intralesional injection. Totally 40 specimens out of 41 mice were suitable for nucleic acid and protein study, including 14 in group A, 13 in group B, and 14 in group C. The hardness of scars showed no significant difference (P gt; 0.05) among 3 groups at 2 weeks after injection, whereas the hardness of scars in group A was significantly lower than those in groups B and C at 4 and 6 weeks (P lt; 0.05), and there was no significant difference between groups B and C (P gt; 0.05). The collagen staining showed the increase of collagentype III in all groups, especially in group A with a regular arrangement of collagen type I fibers. TEM observation indicated that there was degeneration of fibroblasts and better organization of collagen fibers in group A, and the structures of collagen fibers in all groups became orderly with time. The relative expressions of Col I A1 mRNA and the concentrations of Col I A1 protein at 2 and 4 weeks after injection were significant difference among 3 groups (P lt; 0.05), and they were significantly lower in group A than in groups B and C (P lt; 0.05) at 6 weeks after injection, but no significant difference was found between groups B and C (P gt; 0.05). Conclusion Intralesional injection of Col I A1 ASODN in the nude mice model with human hypertrophic scars can inhibit the expression of Col I A1 mRNA and collagen type I, which enhances the mature and softening of the scar tissue. In this process, l iposome shows some assistant effect.
OBJECTIVE: To localize the distribution of basic fibroblast growth factor (bFGF) and transforming growth factor-beta(TGF-beta) in tissues from dermal chronic ulcer and hypertrophic scar and to explore their effects on tissue repair. METHODS: Twenty-one cases were detected to localize the distribution of bFGF and TGF-beta, among them, there were 8 cases with dermal chronic ulcers, 8 cases with hypertrophic scars, and 5 cases of normal skin. RESULTS: Positive signal of bFGF and TGF-beta could be found in normal skin, mainly in the keratinocytes. In dermal chronic ulcers, positive signal of bFGF and TGF-beta could be found in granulation tissues. bFGF was localized mainly in fibroblasts cells and endothelial cells and TGF-beta mainly in inflammatory cells. In hypertrophic scar, the localization and signal density of bFGF was similar with those in granulation tissues, but the staining of TGF-beta was negative. CONCLUSION: The different distribution of bFGF and TGF-beta in dermal chronic ulcer and hypertrophic scar may be the reason of different results of tissue repair. The pathogenesis of wound healing delay in a condition of high concentration of growth factors may come from the binding disorder of growth factors and their receptors. bFGF may be involved in all process of formation of hypertrophic scar, but TGF-beta may only play roles in the early stage.
Objective To study the expression of heat shock protein 47 (HSP47) and its correlation to collagen deposition in pathological scar tissues. Methods The tissues of normal skin(10 cases), hypertrophic scar(19 cases), and keloid(16 cases) were obtained. The expression ofHSP47 was detected by immunohistochemistry method. The collagen fiber content was detected by Sirius red staining and polarization microscopy method. Results Compared with normal skin tissues(Mean IOD 13 050.17±4 789.41), the expression of HSP47 in hypertrophic scar(Mean IOD -521 159.50±272994.13) and keloid tissues(Mean IOD 407 440.30±295 780.63) was significantly high(Plt;0.01). And there was a direct correlation between the expression of HSP47 and the total collagen fiber content（r＝0.386，Plt;0.05）. Conclusion The HSP47 is highly expressed in pathological scartissues and it may play an important role in the collagen deposition of pathological scar tissues.
Objective To observe the differences in protein contents of three transforming growth factorbeta(TGF-β) isoforms, β1, β2, β3 andtheir receptor(I) in hypertrophic scar and normal skin and to explore their influence on scar formation. Methods Eight cases of hypertrophic scar and their corresponding normal skin were detected to compare the expression and distribution of TGF-β1, β2, β3 and receptor(I) with immunohistochemistry and common pathological methods. Results Positive signals of TGF-β1, β2, and β3 could all be deteted in normal skin, mainly in the cytoplasm and extracellular matrix of epidermal cells; in addition, those factors could also be found in interfollicular keratinocytes and sweat gland cells; and the positive particles of TGF-β R(I) were mostly located in the membrane of keratinocytes and some fibroblasts. In hypertrophic scar, TGF-β1 and β3 could be detected in epidermal basal cells; TGFβ2 chiefly distributed in epidermal cells and some fibroblast cells; the protein contents of TGF-β1 and β3 were significantly lower than that of normal skin, while the change of TGF-β2 content was undistinguished when compared withnormalskin. In two kinds of tissues, the distribution and the content of TGF-β R(I) hadno obviously difference. ConclusionThe different expression and distribution of TGF-β1, β2 andβ3 between hypertrophic scar and normal skin may beassociated with the mechanism controlling scar formation, in which the role of the TGF-βR (I) and downstream signal factors need to be further studied.
