Objective To study the effects of dermal template on the biological behaviors of fibroblasts during wound healing. Methods A total of 120 rats were made fullthickness wound modes on the dorsum and divided into 4 groups,in group 1, the wounds were allowed to heal by contraction（ConT）；in group2, the wounds covered with fullthickness skin grafts( FTSG); in group 3, the wounds were with split thickness skin grafts (STSG); and ingroup 4, the wounds were covered by dermal regeneration template with overlying thin splitthickness autograft (ADMT).The specimens were obtained at one week, two weeks, four weeks, six weeks,and twelve weeks respectively. The expressions of α smooth muscle actin(αSMA，characteristic of MFB）,fibronectin(FN),integrin α2,β1 and transforming growth factor β1(TGF-β1) were examined by immunohistochemical analysis. Results Positive expression of α-SMA、FN、integrin α2β1 and TGF-β1 in ADMT groups was significantly lower than that in STSG group and ConT group, but higher than that in FTSG group（P＜0.05）. Conclusion Dermal regeneration template can inhibit the transformation of FB to MFB and restrain the expressionof FN,integrin α2,β1,and TGF-β1 in fibroblasts which might reduce thepossibility of hypertrophyic scaring, and improve wound healing.
Objective To observe the effects of keratinocytes on proliferation and collagen secretion of fibroblasts. Methods The conditioned medium,collected from cultured keratinocytes, was added to the cultured fibroblasts as the tested groups(12.5％, 25% and 50％ groups) and DMEM as control group. The MTT, hydroxyproline coloricmetric method and flow cytometer were employed to measure the fibroblast proliferation, the collagen secretion andthe change of the cell cycle.Results In fibroblast proliferation, the absorbency(A) value of tested groups was significantly different from that of the control group (P＜0.01). A value increased as increasing concentration, there was statistically significant difference betweetheconcentrations of 25%,50% and the concentration of 12.5%(P＜0.01), but no statistically significant difference between the concentrations of 25% and 50%(P＞0.01). In collagen secretion, there was no statistically significant difference between the tested groups and the control group(P＞0.01), and between the tested groups(P＞0.01). In cell cycle, 50% of conditioned medium could make the fibroblast pass the limit of G1/S and S/G2 period, the cell rates of S,G2-M period increased. Conclusion The conditioned medium from keratinocytes can increase fibroblasts proliferation, have little effect on general collagen secretion.
OBJECTIVE: To study the relationship between intracellular actin and scar contracture. METHODS: Fibroblasts from 10 cases of hypertrophic scar and 5 cases of keloid were cultured in vitro. Total actin, filamentous actin(F actin), globular actin (G actin) and the ratio of F to G actin(F/G) were measured by densitometry after differential extraction and separation by polyacrylamide gel electrophoresis in the presence of sodium sulfate. RESULTS: Total actin, F actin, G actin and F/G in hypertrophic scar fibroblasts were 2.38 ng/10(4) cells, 0.98 ng/10(4) cells, 1.42 ng/10(4) cells and 0.68 respectively, while in keloid fibroblasts were 1.68 ng/10(4) cells. 0.46 ng/10(4) cells, 1.26 ng/10(4) cells, and 0.36 respectively. There was significant differences between two tissues fibroblasts in the items of total actin, F actin, G actin, and F/G (P lt; 0.01), while no significant difference in G actin (P gt; 0.05). CONCLUSION: Total intracellular actin, F actin, and F/G may play an important role in the scar contracture. The hypertrophic scar and keloid can be distinguished by the contents of total intracellular actin, F actin and F/G.
Objective To observe the affection of optic nerve under acute ocular hypertension and the effect of protection of bFGF on optic nerve. Methods BSS was perfused into anterior chamber of rabbits to increase the intraocular pressure to cause retinal ischemia. A computer image analysis system was used to count the optic nerve axons.Eyes were intravitreally injected with bFGF and then the number of optic nerve axons of the normal rabbits,and hypertension with and without bFGE treatment groups were counted respectively. Results The number of optic nerve axons in ocular hypertension eyes was less than the normal eyes(P=0.00003).The bFGF treated eyes had more optic nerve axons than the controls(P=0.0078). Conclusions The acute ocular hypertension may cause the loss of the nerve axons,and bFGF may be effective in protecting optic nerve in acute ocular hypertension. (Chin J Ocul Fundus Dis,2000,16:94-96)
Objective To investigate the effect of vanadate on prol iferation and collagen type I production of rat medial collateral l igament (MCL)fibroblasts. Methods A total of 12 adult male SD rats were included, weighing 350-375 g. MCL was cut into small pieces (1 mm × 1 mm × 1 mm) in aseptic conditions, and then placed and cultured in culture chambers. Fibroblasts were passaged with 0.25% trypsin. The vanadate (0, 1.0, 2.5, 5.0 ng/mL) was added in the 3rd passage MCL fibroblasts, respectively, and the samples were divided into 4 groups (0, 1.0, 2.5, 5.0 ng/mL groups). MTT was used to measure the cell prol iferation. The production of collagen type I was measured by RT-PCR and ELISA. Twelve samples in each group were measured. Results In fibroblast prol iferation, the absorbency values of the 1.0, 2.5, 5.0 ng/mL groups were significantly different from that of the 0 ng/mL group (P lt; 0.05). The absorbency values of the 0, 1.0, 2.5, and 5.0 ng/mL groups were 0.213 ± 0.016, 0.327 ± 0.023, 0.449 ± 0.137, and 0.561 ± 0.028, respectively. In collagen secretion, vanadate in 1.0, 2.5, 5.0 ng/mL groups could significantly induce the production of collagen type I (P lt; 0.05) ina dose-dependent manner. The expressions of collagen type I of 0-5 ng/mL groups were 0.47 ± 0.02, 0.51 ± 0.03, 0.60 ± 0.01, and 0.72 ± 0.02, respectively. There was significant difference between the 1.0, 2.5, 5.0 ng/mL groups and 0 ng mL group (P lt; 0.05). RT-PCR displayed a dramatic increase of band density. The ratio of band density in the 0-5 ng mLgroups was 1.37 ± 0.76, 1.97 ± 0.53, 2.41 ± 0.94, and 2.73 ± 0.82, respectively. The gene expression of collagen type I in the 1.0, 2.5 and 5.0 ng/mL groups was higher than that in the 0 ng/mL group, and there was significant difference (P lt;0.05). There were statistical significant differences among 1.0, 2.5 and 5.0 ng/mL groups in each index mentioned above.Conclusion Vanadate can effectively induce the prol iferation of fibroblasts and the production of collagen type I in vitro, which may provide a new approach to the treatment of MCL injury.
Objective To build artificial dermis by using the acellular dermis matrix(ADM), collagen membrane and collagen gel as scaffolds. Methods The fibroblasts were isolated by enzyme from infant skin and were cultivated in the DMEM medium. After 14 days when the fibroblasts were seeded into 3 different scaffolds, the autografts were detected by HE staining, transmission electron microscope and scanning electron microscope. Results ①The fibroblasts obtained from the fullskin by enzyme could be passaged in the Dulbecco’s modified Eagle’s medium 2high gluco se w ith 10% calf bovine serum. ②A layer of fibroblastsw ere found on the surface of th ree different scaffo lds, the fibroblasts could grow into the co llagen membrane and the co llagengel, but could no t be found in the inner of ADM. ③A rt ificial derm is cont racted slightly by inoculat ing fabricat ion on collagen membrane and ADM , and the fibroblasts on them w ere no t act ive in proliferat ing; but the art ificial derm is built by the collagen gel cont racted obviously. Conclus ion The art ificial dermis built by ADM , collagen membrane and collagen gel as scaffolds have a preferable structure for an ideal subst itute of sk n, and can beused as the graft in the next experiments.
Objective To investigate the effect of leptin on fibroblast proliferation and collagen synthesis as to elucidate that fibroblasts play a role in leptin’s effect on wound healing. Methods Purified dermal fibroblasts were derived from sucking wistar rat skin and exposedto leptin at concentration of 0, 10, 50, 100, 200, and 400 ng/ml. The survived fibroblasts were assessed by the colorimetric thiazolyl blue (MTT) assay. Replication of fibroblast was quantified by the incorporation of 3H-thymidine. Collagen synthesis of fibroblast cell was measured by the incorporation of 3H-proline into collagenasesensitive protein. Results The absorption of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 0.082±0.013, 0.091±0.018 was higher than that of control group 0.063±0.010, P＜0.05. The incorporations of 3H-thymidine of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 379±101 cpm,326±33 cpm were significantly higher than those of control group 219±56 cpm, P＜0.05. The incorporations of 3H-proline of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 911±55 cpm, 1 072±259 cpm were significantly higher than that of control group 679±176 cpm, P＜0.05. Conclusion Leptin can promote rat cutaneous fibroblast proliferation and collagen synthesis in vitro. This suggests that cutaneous fibroblast plays a role in leptin’s promoting skin wound healing and it may be one of the main mechanisms by which leptin enhances skin wound healing.
OBJECTIVE: To study the stimulating effects of basic fibroblast growth factor(bFGF) on fibroblast function and its ability to expression of c-fos gene. Furthermore, to explore the possible network action between bFGF and oncogene in modulating wound healing. METHODS: Cultured rat fibroblasts were divided into bFGF stimulating group and control group. Fibroblasts in bFGF stimulating group were treated with bFGF in a dosage of 40 ng/culture hole, while the control fibroblasts were treated with the same vehicle without bFGF. The morphology, cell vitality and their ability to express c-fos gene in the fibroblasts in both groups were studied with MTT and immunohistochemical methods. RESULTS: All fibroblasts in bFGF treated groups were enlarged and showed increased vitality with MTT method. C-fos gene expression in bFGF stimulating group was increased, especially in nucleus when compared with those in control group. CONCLUSION: The results show that the function and the ability to express c-fos gene in bFGF treated fibroblasts are enhanced. Combined with our previous studies, it may make a conclusion that there is a network regulation mechanism between growth factors and some oncogenes.
OBJECTIVE To review the recent advances in fibroblast study and its role in wound repair. METHODS Recent original articles related to wound repair were retrieved extensively, and the effect of fibroblast on every stages of repair were summed up and comprehended. RESULTS Fibroblast plays important roles in granulation formation, wound contraction, matrix synthesis, wound repair, scar formation and scarless repair by means of growth factors modulation. CONCLUSION The understanding of fibroblast in the wound repair can promote the progress of biological therapy of wound repair and scar prevention.
To investigate the best way of using fibroblast growth factor (FGF) in wound healing, the following experiments were performed. Twelve Wistar rats were chosen. Four 1.5 cm x 1.5 cm middle-thick skin wounds were made in the back of each rat, 2 in each side, and labelled as number 1 to 4. Number 1 wound of each rat was used as control, only PBS was applied to the wound, 50 microliters per time, twice a day from the first day to 11th day. Number 2 wound was sustained medication group, 50 microliters 4 micrograms/ml FGF was applied twice a day from the first day to 11th day; Number 3 wound was early medication group, 50 microliters 8 micrograms/ml FGF was applied twice a day from the first day to 5th day; Number 4 wound was late medication group, 50 microliters 8 micrograms/ml FGF was added twice a day from the 5th day to 11th day. By day 4, 8, 12 and 16, the area of wounds were measured, and the healing time of each wound was recorded. The elastic fiber, collagen fiber and DNA content were measured by immunohistological method. The result showed that the elastic fiber, collagen fiber and DNA content in the groups of FGF used were more than those in the control group. The healing time of the control group was 14.4 days while that of the early meduation group was 13.4 days, late medation group was 13.5 days and sustained medication group was 12.2 days. It was suggested that FGF could accelerate the wound healing, and sustained use of FGF was the best way of giving the drug.