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 validate the mechanism of effect of hepatic artery ischemia on biliary fibrosis after liver transplantation and the prevention method. Methods Eighteen male dogs were established into the concise auto orthotopic liver transplantation models and assigned into three groups randomly: hepatic artery ischemia (HAI) group, TBB group (transferred the blood by a bridge duct ) and control group, each group contained 6 dogs. After opening portal vein, the samples were cut from liver in each group at the time of 6 h, 3 d and 14 d. The pathological modifications of intrahepatic bile ducts were observed and expression of transforming growth factor-β1 (TGF-β1) were detected in the three times. Expressions of Smad3 and phosphate-Smad3 as well as mRNA of α-smooth muscle actin (α-SMA) in intrahepatic bile ducts were detected 14 d after opening portal vein.Results Compared with control group, the collagen deposition and lumens stenosis in biliary vessel wall were more obviously in HAI group. In TBB group, the pathological modifications were slighter compared with HAI group. The positive cell index of TGF-β1 reached peak on day 3 after opening portal vein, then decreased in TBB group, and which in HAI group kept increase and was significantly higher than that in TBB group （Plt;0.05）. The expression level of phosphate-Smad3 and transcriptional level of α-SMA mRNA were 1.04±0.13 and 1.12±0.55 in TBB group on day 14 after opening portal vein, which were significantly higher than those in control group (0.59±0.09 and 0.46±0.18) and lower than those in HAI group (1.82±0.18 and 1.86±0.73), the diversities among three groups were significant (Plt;0.05). There was not significant difference of expression of Smads among three groups (Pgt;0.05). Conclusions Hepatic artery ischemia could increase the deposition of collagen fibers and the transdifferentiation of myofibroblast in bile duct and result in the biliary fibrosis by activating the TGF-β1/Smads signaling pathway. The bridging bypass device could lessen the biliary fibrosis caused by hepatic artery ischemia by inhibiting the activation of TGF-β1/Smads signal transduction passageway.
Objective To study the inhibitory effects of curcumin on bleomycin-induced pulmonary fibrosis in rats at the fibrosing stage and explore its possible mechanism.Methods 96 male SD rats were randomly divided into a normal control group，a fibrosis model group，a fibrosis model treated with prednisone group and a fibrosis model treated with curcumin group.Pulmonary fibrosis were induced by instilled bleomycin through tracheal.From day 15 after bleomycin administration，the curcumin group and prednisone group were given curcumin（300 mg/kg） or prednisone（5 mg/kg） per day by intragastric administration，respectively.The normal control group and fibrosis model group were given 1% sodium carboxymethyl cellulose（10 mL/kg） as control.Six rats of each group were randomly sacrificed on day 21，28，42 and 56 after bleomycin administration，respectively.The histological changes of the lung were evaluated by HE and Masson’s trichrome staining.Lung expressions of transforming growth factor-β1（TGF-β1） and hydroxyproline were assessed by immuno-histochemistry and digestion method，respectively.Results Pulmonary fibrosis and hydroxyproline level in the curcumin group were significantly reduced as compared with those in the model group on day 42 and 56.The expession of TGF-β1 in the curcumin group was significantly lower than that in the model group on day 28，42 and 56，and was not significantly different from the normal group on day 56.Conclusion Curcumin could alleviate bleomycin-induced pulmonary fibrosis in rats at the fibrosing stage by inhibiting the expressions of TGF-β1.
Objective To investigate the expression of vascular endothelial growth factor-A （VEGF-A） and the phenotypic transition after the activation of fibroblasts by the supernatant of cultured tumor cells．Methods The growth tendency of fibroblasts was tested by the MTT assay．The expressions of alpha-smooth muscle actin （α-SMA） and VEGF-A mRNA were tested by RT-PCR．The expressions of α-SMA and VEGF-A protein were tested by immunohistochemistry and Western blot．Results The MTT assay indicated that the conditional medium which contained tumor cells supernatant could obviously promote the growth of the fibroblasts． RT-PCR and Western blot manifested that α-SMA expressed by the fibroblasts which cultured by normal medium reached its peak on day 5，then decreased to a low level on day 7．When the medium contained 2 ng/ml transforming growth factor-β1 （TGF-β1），the fibroblasts could steadily express more α-SMA．But the above two mediums could not make the fibroblasts express the VEGF-A. When using the conditional medium，the α-SMA peak advanced on the third day and maintained at a high level，so as the expression of the VEGF-A．Conclusions The results suggested that fibroblasts can be activated to be myofibroblasts when using the conditional medium．The best activation time of the fibroblasts is consistent with the time of the VEGF-A expression at the highest level by the activated fibroblasts．The fibroblasts which activated at the best time are expected to become a kind of cells which can be used for promoting revascularization．
Objective To investigate the effect of imatinib mesylate on radiation-induced lung injury mice and its influence on the oxidative stress and transforming growth factor-β1 (TGF-β1) expression in mice. Methods Forty-five C57BL/6 mice were divided into a treatment group, a control group and a model group. The treatment group and model group were given radiation of 18 Gy delivered in the thorax. After 4 h daily of the radiation, the treatment group received imatinib mesylate of 0.081 g/kg, while the other groups were given normal saline solution. The experiments were continued for 30 days. After the experiments, the lungs of mice were divided into 4 parts. The haematoxylin and eosin and immunohistochemical stain were prepared to observe the situation of pathology and TGF-β1. The lung homogenate was prepared and the levels of superoxide dismutase (SOD), malondialdehyde (MDA), total antioxidant capacity (T-Aoc) and glutathione peroxidase (GSH-PX) were detected. Results The levels of GSH-PX, T-Aoc and SOD were (173.15±12.21) U, (119.33±11.06) U/mgprot and (1.73±0.33) nmol/mgprot in the treatment group, significantly higher than the control group, while the levels of MDA was (0.68±0.08) nmol/mgprot, significantly lower than the control group (P<0.05). The HE and immunohistochemical stain showed that there were mild alveolar inflammatory changes in the treatment group while such changes were serious in the model group. The scores of HE and immunohistochemical were 1.26±0.12 and 0.31±0.12 in the treatment group, significantly lower than those in the control group (P<0.05). Conclusion The imatinib mesylate can effectively ameliorate the oxidative stress and inhibite TGF-β1 expression in radiation-induced lung injury mice.
Objective To review the recent advances in transforming growth factor-β(TGF-β) super family study and its role in new bone formation. Methods The latest original articles related to this subject were retrieved extensively,especially the effect of TGF-β, bone morphogenetic proteins(BMPs) and activin(ACT) on distractionosteogenesis. Results TGF-β, BMPs and ACT play important roles in prompting new bone formation and each of them has different effects. Among them, TGF-β can stimulate the proliferation of osteoblast and synthesis ofextra cellular medium; BMPs can initiate the differentiation of interstitial cell toosteocyte; then ACT displays the combine effect of above two factors. Conclusion TGF-β superfamily can regulate new bone formation and thus shorten the course of mandibular distraction osteogenesis.
ObjectiveTo summarize the research advancement of peroxisome proliferator-activated receptor γ (PPARγ) agonists inhibiting transforming growth factor-β (TGF-β)-induced organ fibrosis. MethodsThe related literatures on PPARγ agonists inhibiting TGF-β-induced organ fibrosis were reviewed. ResultsTGF-β was a major fibrosispromoting cytokine, which could promote a variety of organ fibrosis. PPARγ agonists could effectively block TGFβ signal transduction, and then suppressed organ fibrosis well. ConclusionsThe main antifibrotic mechanism of PPARγ agonists is to inhibit TGF-β signal transduction. The studies on this mechanism will help promoting the clinical application of PPARγ agonists, and provide a new way of the treatment for organ fibrosis.
Objective To study the influence of transforming growth factor-β1(TGF-β1), dentin non-collagen proteins(dNCPs) and their complexon tissue engineering pulp system. Methods Collagen I and dentin powder were used to construct the system of pulp cells in 3dimensional culture, dentin powder was added in the gel. The tissue engineering pulp were divided TGF-β1 group, dNCPs group, TGF-β1/dNCPsgroup and control group.After3, 6 and 14 days, the appearance and the differentiation of pulp cells were observed by HE staining and immunohistochemical staining -respectively. Results Collagen I could form netted collagen gel construction. Growing condition of pulp cells in gel was similar to that of pulp cells in vivo. After the TGF-β1 and dNCPswere added, the pulp cells had some characteristics of odontoblasts and had unilateral cell process after culture 6 days. Pulp cells arranged with parallel columnar and form dentin-pulp-like complex after 14 days. Immunohistochemical staining showed dentin salivary protein(DSP) began to express in some cells.The number of positive cell was most in the TGF-β1 group. No positive cells were detected in the control group. Conclusion The transforming growth factor-β1 and noncollagen proteins can stimulate the pulp cells to transform into odontoblasts to some extent, which promote the formation of tissue engineering pulp.
Objective To explore the treatment effect of bone marrow mesenchymal stem cells( BMSCs)transplantation in ratmodel of bleomycin-induced pulmonary fibrosis. Methods BMSCs fromten-day-old SDmale rat were cultured and marked with 4, 6-diamidino-2-phenylindole( DAPI) . Seventy female SD rats were randomly divided into four groups. Group A( n = 21) was intratracheally injected with saline as control. Group B( n = 21)were intratracheally injected with BLMA5 to establish pulmonary fibrosis. Group C( n = 21) was injected with BLMA5 intratracheally and BMSCs intravenously via tail vein simultaneously. Group D( n = 7) was injected with BMSCs 14 days after BLMA5 injection. The rats were sacrificed on 7th, 14th and 28th day respectively( rats of group D were on28th) . HE and Masson stainings were performed to observe lung pathological changes. Fluorocyte marked with DAPI was analyzed by fluorescent microscope. Sex determining region Y( SRY) gene were detected by PCR. The lung levels of HYP, tumor necrosis factor-α( TNF-α) and transforming growth factor-β1 ( TGF-β1 ) were measured by ELISA. Results ( 1) In group C and D, BMSCs marked with DAPI were detected in lung frozen section on 7th, 14th and 28th day, and SRY gene of male rats were detected by PCR. ( 2) Alveolitis was most obvious on 7th day and pulmonary fibrosis was most severe on 28th day in group B compared to other three groups( P lt;0. 05 or 0. 01) . Alveolitis and pulmonary fibrosis in group C and D were significantly alleviated compared to group B( P lt; 0. 05) , but still more severe than group A( P lt; 0. 05 or 0. 01) , which in group D was more severe compared to group C( P lt;0. 05) . ( 3) HYP level in group B, coincided with fibrosis, began to increase on7th day and reached the peak on 28th day, significantly higher than other three groups( P lt;0.05 or 0. 01) . TNF-αlevel in group B was highest on 7th day, then descended, which was significantly higher than group A and C on 14th day and not obviously different from other three groups on 28th day. TGF-β1 level in group B was highest on 28th day which was different significantly fromother three groups. Conclusion BMSCs can colonize in the recipient lung tissue and effectively prevent the development of pulmonary fibrosis of rats induced by BLMA5, especially in the early stage.