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.
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 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.
【摘要】 目的 原肌球蛋白是肌球蛋白主要相关蛋白之一，在细胞骨架与运动中起着重要的作用。探讨原肌球蛋白在增生性瘢痕中的作用，有助于揭示瘢痕挛缩的产生机制。 方法 收集2006年3月-2008年7月48例患者不同时期增生与非增生瘢痕组织标本，利用基因芯片筛选出的瘢痕相关基因——原肌球蛋白基因特异片段，制备成寡核苷酸探针与瘢痕组织切片进行原位杂交。同时，将各标本进行原代细胞培养，制备成纤维细胞爬片，进行原位杂交。 结果 原肌球蛋白基因在3、6个月的增生性瘢痕中表达均明显强于9、12个月增生性瘢痕及非增生性瘢痕，阳性细胞比例也高于9、12个月增生性瘢痕及非增生性瘢痕。 结论 瘢痕增生挛缩与细胞骨架运动的相关基因存在密切关系，而原肌球蛋白可能在其中起着重要作用。【Abstract】 Objective Tropomyosin is one of the proteins of cytoskeleton and cell movement. The aim of this study is to investigate the effect of gene expression of fibroblast tropomyosin on the formation and contraction of hypertrophic scar. Methods According to the results of differently expressed genes, in hypertrophic scar by gene microarray, topomyosin, one of the most important genes, was selected and made into oligonucleotide probe. Twenty-four hypertrophic scars and 24 non-hypertrophic scars and 12 normal skins were used and these scar were taken on 3, 6, 9, and 12 months after burned between March 2006 and July 2008. Frozen section and cultured fibroblasts were made to detect the expression of the gene by in situ hybridization. Results Expression of tropomyosin was defected in scar tissue, but those in the hypertrophic scar on 3 and 6 months after burn were significantly ber than those in the hypertrophic scar on 9 and 12 months after burn and non-hypertrophic scar. Conclusion Overexpression of cytoskeletal relative genes causes the contraction of scar and tropomyosin acts leading and key functions.
Objective To study the effect and mechanism of the apoptosis of hypertrophic scar fibroblasts (HSF) induced by artesunate(Art). Methods HSFs were isolated and cultured from human earlobe scars by the tissue adherence method. The 3th to 5th generation cells were harvested and divided into two groups. HSF was cultured with normal medium in control group and with medium containing60, 120 and 240 mg/L (5 ml)Art in experimental group. Apoptosis and cell cycle were identified by light microscopy, electronmicroscopy and flow cytometry. Then, HSF was cultured with normal medium in control group and with medium containing 30, 60 and 120 mg/L Art in experimental group. The changes of intracellular calcium concentration were observed. Results The primary HSF was fusiform in shape and adherent. The vimentin positive expression was analyzed by immunocytochemistry. Art could induce apoptosis of HSF in the range of 60-240 mg/L under inverted microscope. The effect was dose and timedependent. Clumping of nuclear chromatin showed margination in the experimentalgroup. And the disaggregation of the nucleolus were observed under electronmicroscopy. There were significant differences in the proportion of HSF apoptosis and HSF at G0-G1,S, G2-M stages between the two groups(P＜0.05). Apoptotic peak was shown in experimental group by flow cytometry. The peak became more evident asArt concentration increased. The intracellular calcium concentration elevated markedly in HSF with 30-120 mg/L Art treatment for 24 hours, showing significant differences between the two groups (P＜0.05). Conclusion The Art facilitates HSF cells apoptosis in vitro by the change of cell cycle. It is suggested that intracellular calcium variation may be one of the mechanisms of HSF apoptosis induced by Art.
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.
In order to study the biological properties of fibroblasts isolated from different tissues. The fibroblasts from normal skin, hypertrophic scar and keloid were cultured, respectively, in vitro, and their morphologies and growth kinetics were compared. The results revealed that although fibroblasts in keloid were irregularly arranged, crisscross and overlapping with loss of polarization, there was no significant difference in the 3 groups so far the cellular morphology of fibroblast itself, cellular growth curve, cellular mitotic index, cloning efficiency and DNA content provided those cultures were in the same cellular density and culture conditions. It was concluded that fibroblasts isolated from culture of normal skin, hypertrophic scar and keloid in vitro showed no significant difference in morphology and growth kinetics, on the contrary, their biological behaviors were quite similar.
OBJECTIVE: To observe the protein expression of phosphorylated form of P38 mitogen-activated protein kinase(P38MAPK) and c-Jun in hypertrophic scar skin and to explore their influences on the formation and maturation of hypertrophic scar. METHODS: The expression intensity and distribution of phosphorylated form of P38MAPK and c-Jun were examined with immunohistochemistry and pathological methods in 16 cases of hypertrophic scar skin and 8 cases of normal skin. RESULTS: In normal skin, the positive signals of phosphorylated form of P38MAPK mostly distributed in basal lamina cells of epidermis, while c-Jun was mainly located in epidermal cells and endothelial cells. The positive cellular rates of two proteins were 21.3% +/- 3.6% and 33.4% +/- 3.5% respectively. In proliferative hypertrophic scar skin, the particles of phosphorylated P38MAPK and c-Jun were mainly located in epidermal cells and some fibroblasts. The positive cellular rates of two proteins were significantly elevated to 69.5% +/- 3.3% and 59.6% +/- 4.3% respectively (P lt; 0.01). In mature hypertrophic scar, the expression of these proteins decreased but was still higher than that of normal skin. CONCLUSION: The formation and maturation of hypertrophic scar might be associated with the alteration of phosphorylated P38MAPK and c-Jun protein expression in hypertrophic scar.
【Abstract】 Objective To investigate the angiogenesis in hypertropic scar tissue of rabbit ears at different periods and to explore a new method to prevent hyperplastic scar. Methods Nineteen Japanese white rabbits(weigthing 2.0-2.5 kg) were made animal models of hypertropic scar of ear. At 10th, 30th, 60th and 90 days, after epithel ization, the microvessel and microcirculation in hyperplastic scar of 8 rabbits were studied by microcirculation microscope and laser Doppler flowmetry. The other 11 rabbits’ right or left ears were randomly chosen into experimental group and control group. At 10 days after epithel ization,40 μL of adenovirus extracellular protein with metalloprotease and thrombospondin 1 domains (Ad-METH1) was injected into tissue of scar along the perimeter of the scar in experimental group. The same volume of empty adenovirus was injected in control group. After 30 days of injection, the gross appearance of 10 rabbits’ ears scar was recorded, the number of microvessel in scarwas counted and HE stainning of scar tissue was performed in experimental and control groups. One additional rabbit was used to evaluate the mRNA and protein expression of METH1 by RT-PCR and Western blot after 3 days of injection. R e sults The average number of microvessel at 10, 30, 60 and 90 days after epithel ization was 42.37 ± 3.89, 49.46 ± 4.13, 33.12± 4.34 and 13.24 ±2.31, respectively; the average value of microcirculatory perfusion at 10, 30, 60 and 90 days after epithetl ization was (37.75 ±2.11), (59.87 ± 6.46), (44.53 ± 6.14) and (29.21 ± 1.84)PU; the density of microvessels and perfusion of microcirculation in scar tissues during prol iferative stage (from 10 to 60 days after epithel ization) were markedly higher than that during mature period (90 days after epithel ization, P lt; 0.05).At 10 to 30 days after epithel ization, the histol igical features of scar showed early stage of prol iferation and prol iferative stage appearance; at 60 days after epithel ization, it is still in prol iferative stage, while some of scars were in mature phase; at 90 days after epithel ization, the histol igical features of scar were mature period appearance. At 3 days after Ad-METH1 injection, METH1 gene was successfully expressed at both mRNA and protein levels in experimental group, but not in control group. At 30 days after injection, the gross appearanceobservation showed that scars in experimental group were flat and soft with the color close to normal, but scars incontrol group were obvious and hard. The number of microvessel of scar tissue was 12.38±2.56 in experimental group and 48.12±6.46 in control group, showing statistically significant difference between two groups(P lt; 0.01). In experimental group, HE staining shows that the density of microvessel and the number of fibroblasts were greatly decreased and collagen fibers arranged regularly. In control group, plenty of fibroblasts and abundant microvessels were observed. Thick and tight collagen fibers were seen in the outer layer of dermis with a irregular arrangement. Conclusion Theanti-angiogenesis by Ad-METH1 may have a promising appl ication in the prevention of human hyperthropic scar.
OBJECTIVE To study the influence and mechanism of gamma-IFN on fibroblasts in hypertrophic scars(HTS). METHODS The cultured fibroblastic cells were isolated from the hypertrophic scars of 10 patients. The fibroblasts were divided into two groups, one group was treated with gamma-IFN (100 U/ml, 5 days) and the other without gamma-IFN as control. The proliferative activity in both groups was investigated and compared by blood cytometer, the proportion of myofibroblast (MFB) and the ratio of apoptosis were examined and analysed between two groups by flow cytometry using alpha-smooth muscle actin (alpha-SMA) as marker. RESULTS The proliferative activity was downregulated with gamma-IFN. In gamma-IFN treated group, the differentiation of MFB were reduced and the decreasing ratio was 3.2% at the 2nd day and up to 10.5% at the 8th day, then it reduced gradually. The apoptosic ratio is 17.7% in gamma-IFN treated group, and is 10.9% in control group. The difference was statistically significant. CONCLUSION gamma-IFN could downregulate the proliferation of fibroblasts, decrease the differentiation of MFB and induce the apoptosis. It has beneficial effect in the treatment of hypertrophic scars(HTS).