OBJECTIVE: To explore the relationship between the expression change of cytokines and the wound age during the healing process of rats skin wound. METHODS: Immunohistochemical and image-analysis methods were performed on vital skin wounds(after incision 0.5-168 h am) and postmortem damage(after incision 0.5-6 h pm). RESULTS: The expression of the cytokines PDGF-beta, PDGFR-beta, TGF-beta 1, and bFGF in the epithelial cells was already enhanced since 0.5 h am after damage and their strongest expression reaction was seen at 24-96 h am. In addition, the expression of PDGF-beta, PDGFR-beta, TGF-beta 1 and bFGF was also found in the macrophages and the fibroblasts of the granulation tissue, and the expression changes in the postmortem damage group showed that the skin tissue within 0.5-3 h after incision showed immunohistochemical changes but weakly expression and 3 h thereafter no any change was found. CONCLUSION The expression characteristics of the above mentioned cytokines in wound repair should be related to the wound age and it reminds therefore that they may be used as immunohistochemical criteria for accurate determining the wound age.
Animals ; Cytokines/biosynthesis* ; Female ; Fibroblast Growth Factor 2/biosynthesis* ; Male ; Platelet-Derived Growth Factor/biosynthesis* ; Rats ; Rats, Wistar ; Receptor, Platelet-Derived Growth Factor beta/biosynthesis* ; Skin/metabolism* ; Time Factors ; Transforming Growth Factor beta/biosynthesis* ; Transforming Growth Factor beta1 ; Wound Healing

OBJECTIVETo study the expression and significance of platelet derived growth factor (PDGF) and its receptor (PDGFR) in liver tissues of patients with chronic hepatitis fibrosis and liver cirrhosis.

METHODSThe expression, distribution, quantitation, and correlation of PDGF-A, PDGF-B, PDGFR-alpha, PDGFR-beta, and alpha-SMA in the liver tissues were analyzed by immunohistochemical techniques in 21 patients with chronic hepatitis and 42 patients with liver cirrhosis.

RESULTSIn the liver tissues of chronic hepatitis and liver cirrhosis, PDGF and its receptor and alpha-SMA mainly distributed in the fibrotic septa and the infiltration area of inflammation, particularly in branch spindle-shaped cells (activated HSC). The expression of PDGF-B and PDGFR-beta was stronger than that of PDGF-A and PDGFR-alpha with a significant difference between them (P<0.05 approximately 0.01). The expression and distribution of alpha-SMA was basically identical with the expression and distribution of PDGF-A, PDGF-B and PDGFR-alpha, PDGFR-beta and quantitative analysis showed a positive correlation (r=0.606, P<0.001).

CONCLUSIONSPDGF and PDGFR play a key role in liver fibrogenesis and development. The biologic effects of PDGF are elicited through activising HSC. Inhibiting PDGF and its receptor is a new approach to the treatment of liver fibrosis.

Actins ; biosynthesis ; physiology ; Adolescent ; Adult ; Aged ; Female ; Hepatocytes ; metabolism ; Humans ; Liver Cirrhosis ; metabolism ; Male ; Middle Aged ; Muscle, Smooth ; chemistry ; Platelet-Derived Growth Factor ; biosynthesis ; physiology ; Proto-Oncogene Proteins c-sis ; biosynthesis ; physiology ; Receptor, Platelet-Derived Growth Factor alpha ; biosynthesis ; physiology ; Receptor, Platelet-Derived Growth Factor beta ; biosynthesis ; physiology

To explore the role of platelet derived growth factor-AA (PDGF-AA) and PDGFR-alpha expression in the proliferation and hypertrophy of vascular smooth muscle cells (VSMCs) in spontaneously hypertension rats (SHR), protein expression of PDGF-AA, PDGFR-alpha and PDGFR-beta in SHR/Wistar-Kyoto (WKY)-VSMC was observed by Western blot. Proliferation and hypertrophy of SHR-VSMCs induced by PDGF-AA were observed by measurement of PCNA and [(3)H] incorporation. PDGF-AA and PDGFR-alpha expression was markedly increased in SHR-VSMCs compared with that in WKY-VSMCs, but PDGFR-beta was not different in SHR and WKY-VSMCs. PDGF-AA induced PCNA expression and [(3)H] incorporation was increased in a dose-dependent manner in SHR, but not in WKY. It is suggested that an enhancement of PDGF-AA and PDGFR-alpha in SHRs may be one of the important factors for vascular modeling.
Animals ; Cell Division ; drug effects ; Cells, Cultured ; Hypertension ; physiopathology ; Male ; Muscle, Smooth, Vascular ; cytology ; drug effects ; metabolism ; Platelet-Derived Growth Factor ; biosynthesis ; pharmacology ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY ; Receptor, Platelet-Derived Growth Factor alpha ; biosynthesis

OBJECTIVETo investigate the dynamic expression of platelet-derived growth factor-A (PDGF-A) and its receptor alpha (PDGFR-alpha) in different acute radiation-induced skin ulcers, and to explore the underlying mechanism involved in retarded healing of the ulcer.

METHODSThe model of acute radiation-induced skin ulcers in rats was replicated with 50 Gy 60Co gamma rays to the skin (radiation group, R, n = 55), rats with full - thickness skin excision wounds as control group (T, n = 55), and 5 normal rats to serve as normal control (NC) group. The expression of PDGF-A and PDGFR-alpha protein and PDGF-A mRNA was respectively assessed by means of histochemistry and in situ RT-PCR.

RESULTSNo PDGF-A expression was identified in the rat skin in NC group. The expression of PDGF-A and PDGFR were reduced in R group during inflammatory responsive and granulation formation periods (14 - 28 days after radiation, the IA value of PDGF-A varied from 14.0 +/- 1.2 to 20.3 +/- 1.2 compared with that in T group in which the IA value of PDGF-A at the same period (3 - 9 days after injury) varied from 20.0 +/- 1.6 to 28.3 +/- 1.0, and reduced gradually during scar formation period (55 days after radiation).

CONCLUSIONThe reduction of PDGF-A and PDGFR-expression may be partially involved in the mechanism of retarded healing of acute radiation-induced skin ulcers.

Animals ; Female ; Gamma Rays ; adverse effects ; Platelet-Derived Growth Factor ; biosynthesis ; Radiation Injuries, Experimental ; complications ; metabolism ; Rats ; Rats, Wistar ; Receptor, Platelet-Derived Growth Factor alpha ; biosynthesis ; Skin Ulcer ; etiology ; metabolism ; Wound Healing

The influence of platelet-derived growth factor (PDGF) on lung development in newborn rats and the effect of retinoic acid (RA) on PDGF in lung development were investigated. Newborn Sprague-Dawley (SD) rats were randomly assigned to two groups: control group and RA group. The rats in RA group was intraperitoneally injected with all trans-retinoic acid (500 microg/kg every day) for consecutive 3 days after birth, while those in the control group were not subjected to intervention. Immunohistochemical assay was performed to locate the expression of PDGF. mRNA levels of PDGF were measured by reverse transcription polymerase chain reaction (RT-PCR) at age of 1, 3, 5, 7, 10, 14, 21 days. The method of radial alveolar counts (RAC) was used to measure the amount of the alveoli of the lungs. It was found that with increasing days, levels of PDGF-A and PDGF-B changed to verying degrees. RA could elevate significantly the expression levels of PDGF-A mRNA and protein (P<0.01), but not affect the expression levels of PDGF-B mRNA and protein markedly (P>0.05). It is suggested that PDGF might play an important role in lung development. RA can stimulate lung development through increasing the expression levels of PDGF-A mRNA and protein.
Animals ; Animals, Newborn ; Lung ; growth & development ; metabolism ; Platelet-Derived Growth Factor ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Tretinoin ; pharmacology

Cell Line ; Epidermal Growth Factor ; biosynthesis ; genetics ; Fibroblast Growth Factor 2 ; biosynthesis ; genetics ; Hepatocytes ; metabolism ; Humans ; Interleukin-10 ; pharmacology ; Platelet-Derived Growth Factor ; pharmacology ; Proto-Oncogene Proteins c-sis ; RNA, Messenger ; biosynthesis ; genetics

OBJECTIVETo investigate the regulatory effect of interleukin-10 (IL10) on the activation of hepatic stellate cells (HSC) through platelet derived growth factor (PDGF) and mitogen-activated protein kinase (MAPK) pathways.

METHODSHSC were divided randomly into 4 groups. Group 1 served as a control. HSC were incubated with 1 ng/ml, 5 ng/ml, and 25 ng/ml IL-10 in groups 2, 3 and 4. RT-PCR and western blot were used to detect the expression of PDGF and MAPK protein ERK and p38 and alpha-SMA.

RESULTSCompared with the control group, expressions of ERK, p38 and alpha-SMA of groups 2, 3 and 4 were significantly lower (F values were 240.47, 21.39, 28.86 respectively. IL-10 inhibited PDGF and MAPK protein ERK and p38 and alpha-SMA expression in a dose-dependent way.

CONCLUSIONIL-10 inhibits activation of HSC through the PDGF/MAPK pathway.

Animals ; Cell Line ; Cell Proliferation ; drug effects ; Hepatocytes ; cytology ; drug effects ; Interleukin-10 ; pharmacology ; Mitogen-Activated Protein Kinases ; biosynthesis ; Platelet-Derived Growth Factor ; biosynthesis ; Rats ; Signal Transduction

OBJECTIVETo acquire sufficient PDGF-BB protein and provide the basis for the further studies of its role on the fracture healing and trauma reconstruction and its clinical applications.

METHODSConstructed the prokaryotic expression vector pQE-PDGF-B with the gene rearrangement technique, and the monomeric form of recombinant PDGF-B expressed in E. coli M15.

RESULTSPDGF-B mature peptide gene was inserted into prokaryotic expression vector pQE30, which was confirmed by PCR, enzyme digestion and sequencing identification; the expressed products of pQE-PDGF-B in E. coli showed a single protein on SDS-PAGE, and their expression level was about 15% of the total bacterial protein. The molecular weight of the purified PDGF-B protein was about 15 KDs on SDS-PAGE.

CONCLUSIONSThe construction of recombinant plasmid and preparation of the monomeric protein of PDGF-B provides a solid foundation for further studying the function of PDGF-BB and producing biologically PDGF-BB protein.

Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Genetic Vectors ; Humans ; In Vitro Techniques ; Platelet-Derived Growth Factor ; biosynthesis ; genetics ; Proto-Oncogene Proteins c-sis ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; Transfection

To explore the biological effects of shear stress on intact artery and the change of growth factor during stress-induced vascular remodeling, we established an artery organ-cultured system under stress in vitro, and the common carotid arteries of pigs were cultured under shear stress of 20, 5 and 0 dyn/cm2. PDGF-A synthesis of vascular smooth muscle cells (VSMCs) cultured for 1, 4 and 7 days were studied by immunohistochemical and computer image processing methods, and PDGF-B secretion of endothelial cells (ECs) cultured within 12 h were studied by ELISA. Results showed that PDGF-B increased obviously under shear stress of 5 dyn/cm2, and reached the highest point at about 3 h; PDGF-A synthesis also obviously increased under low shear stress in 7 days. Increasing of PDGF synthesis promotes phenotype switch and proliferation of VSMC. It may have important influence on artery remodeling under low shear stress.
Animals ; Carotid Artery, Common ; chemistry ; metabolism ; Cells, Cultured ; Endothelium, Vascular ; cytology ; metabolism ; Muscle, Smooth, Vascular ; cytology ; metabolism ; Platelet-Derived Growth Factor ; biosynthesis ; Shear Strength ; Stress, Mechanical ; Swine

AIMTo investigate whether AcSDKP can inhibit proliferation and collagen synthesis in cultured rat cardiac fibroblasts mediated by PDGF.

METHODSNeonatal rat cardiac fibroblasts were isolated. The cell proliferation was observed by 3H-proline incorporation assay.

RESULTSOn the culture of 0.4% FBS, PDGF stimulated cardiac fibroblasts proliferation and collagen synthesis with a dose-dependent manner at the concentrations from 1 ng/ml to 20 ng/ml, in which 10 ng/ml PDGF reached its peak. AcSDKP at the concentration from 10(-10) mol/L to 10(-8) mol/L could inhibit cardiac fibroblasts proliferation and collagen synthesis mediated by PDGF. 10(-9) mol/L AcSDKP attained its peak on inhibiting cardiac fibroblasts proliferation and collagen synthesis.

CONCLUSIONAcSDKP can inhibit proliferation and collagen synthesis in cultured rat cardiac fibroblasts mediated by PDGF.

Animals ; Cell Proliferation ; Cells, Cultured ; Collagen ; biosynthesis ; Fibroblasts ; cytology ; drug effects ; metabolism ; Myoblasts, Cardiac ; cytology ; drug effects ; metabolism ; Oligopeptides ; pharmacology ; Platelet-Derived Growth Factor ; pharmacology ; Rats ; Rats, Wistar