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Aim To investigate the therapeutic effect of SirTl agonist resveratrol on IgA nephropathy rats and its mechanisms. Methods An IgA nephropathy rat model was established. The rats were divided into four groups randomly: control group, IgA nephropathy group, control treated with Res group and IgA nephropathy treated with Res group. The urine protein was detected by Ponceau S; the biochemical indexes were detected by automatic biochemical analyzer; the pathological changes of kidney were observed by PAS and Masson staining; IgA deposition was observed by immunofluorescence; the expressions of PDGF-B and TGF-fil were detected by immunohistochemistry. Results Compared with IgA nephropathy group, the volume of 24-hour urinary protein and the expression of BUN and Scr in Res group decreased significantly, and the fluorescence of IgA in glomerulus was less in resveratrol group; mesangial cells and matrix proliferated and glomerular volume increased in IgA nephropathy group at the later stage, and both of them were significantly inhibited. Resveratrol could significantly reduce the high expression of PDGF-B and TGF-β1 in IgA nephropathy group. Conclusions Res can inhibit the deposition of IgA immune complex in mesangial region of IgA nephropathy rats and reduce glomerulosclerosis by down-regulating the expression of PDGF-B and TGF-β1, in turn it suppresses cell proliferation in mesangial region. It suggests that resveratrol plays an important role in slowing down the progression of IgA nephropathy.
ABSTRACT
To observe the immunogenicity of hPDGF-B immunogens that were synthesized with the fusional expression vector pET28-Trx and to test the suppressive effect of these specific antibodies induced by both of immunogens on proliferation of human HepG2 hepatoma cells. First, we chose 2 antigenic epitopes hPDGF-BΔ103-118aa and hPDGF-BΔ152-167aa from human PDGF-B and inserted these 2 coding regions into the empty vector plasmid pET28-Trx, separately. Second, mice were immunized with purified recombinant proteins to generate polyclonal antibody. Then we intraperitoneally injected mice bearing hepatoma 22 (H22) tumor cells to prepare antibody ascites. ELISA and Western blot were used to detect the titer and the utility of the antibody, respectively. Finally, HepG2 cells were exposed to PDGF-BB protein or anti-PDGF-B ascite antibody in different dilution concentrations groups and the proliferation of HepG2 cells was quantified by CCK8 assay. As the results, we identified mice that could produce high drop of neutralizing antibodies against hPDGF-B induced by both two recombinant proteins. Two anti-PDGF-B ascite antibodies could markedly inhibit the proliferation of HepG2 cells by blocking the stimulating effect of PDGF-BB protein. Our results suggest that Trx-PDGF-B recombinant protein as immunogen provides a new method for the preparation of PDGF-B vaccine, and also a new idea for the treatment of hepatocellular carcinoma in clinical practice.
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Objective To observe the effects of Hedysari Polysaccharide (HPS) on the expressions of TSP-1 and PDGF-B in the retina of diabetic rats;To discuss the protective effect and possible mechanism on diabetic retinopathy. Methods The diabetic model was established by intraperitoneal injection of streptozotocin. 50 male SPF Wistar rats were randomly divided into 5 groups:model group, calcium dobesilate group, and HPS high-, medium-, and low-dose group, extra 10 rats were set as the normal group, 10 rats in each group. Each administration group was given relevant medicine for gavage, while model group and normal control group were given same amount NS for gavage, once a day for 8 weeks. The mRNA and protein expression of TSP-1 and PDGF-B were detected by qRT-PCR and immunohistochemistry. The retinal structure was observed by HE staining. Results HE staining showed that each layer of the retina of the model group was clear and complete, but the outer nucleus layer became looser, thinner and more disorderly, and the number of ganglion cells decreased slightly; the administration groups were improved markedly compared with the model group. Compared with the normal control group, the mRNA level and protein expression of retina TSP-1 on the model group dramatically dropped (P<0.01), and those of PDGF-B strikingly increased (P<0.01);Compared with the model group, the mRNA level and protein expression of retina TSP-1 on alladministration groups rose (P<0.05, P<0.01), and those of PDGF-B went down (P<0.01); Compared with all other administration groups, there was statistical significance in the mRNA level and protein expression of retina TSP-1 and PDGF-B on HPS high-dose group (P<0.05, P<0.01). Conclusion HPS may prevent the angiogenesis and proliferation in diabetic retinopathy process through adjusting the content of TSP-1 and PDGF-B in retina of diabetic rats so as to protect the retina.
ABSTRACT
BACKGROUND: Insulin-like growth factor-I (IGF-I) shares a high degree of structural and functional homology with insulin and is a potent mitogen supporting cell growth and survival in many kinds of the tissues and cells. It also plays a role in some differentiation and anti-apoptotic functions. In previous reports, it has been shown that IGF-I stimulates hair follicle (HF) growth, maintains the anagen stage, and postpones the catagen stage. OBJECTIVE: The exact mechanism of the effect of IGF-I on HF growth is not yet established. Therefore, we investigated the relationships between IGF-I and various other factors (i.e. apoptosis related molecules, pro-inflammatory cytokines, other growth factors, etc.) in the control of HF growth. METHODS: The effect of IGF-I on human hair growth was measured using an organ culture model of human HFs and compared with a control group that did not receive IGF-I. We also measured mRNA expression of factors related to hair growth and apoptosis (which was determined by reverse transcription polymerase chain reaction (RT-PCR). RT-PCR was done on days 2, 4, 6, and 8 of organ culture. RESULTS: In organ cultured human hair follicles, IGF-I had a positive effect on the rate of linear hair growth. IGF-I maintained the anagen phase. IGF-I increased the expression of platelet-derived growth factor (PDGF)-A, PDGF-B and the expression ratio of Bcl-2/Bax. CONCLUSION: The effect of IGF-I on hair growth appears to be related to the upregulation of PDGF-A and PDGF-B and to the anti-apoptotic effect of IGF-I.
Subject(s)
Humans , Apoptosis , Cytokines , Hair , Hair Follicle , Insulin , Insulin-Like Growth Factor I , Intercellular Signaling Peptides and Proteins , Organ Culture Techniques , Platelet-Derived Growth Factor , Polymerase Chain Reaction , Reverse Transcription , RNA, Messenger , Up-RegulationABSTRACT
Unilateral ureteral obstruction(UUO) results in severe renal vascular constriction through the activation of renin-angiotensin system, which causes progressive tubulointerstitial fibrosis. Platelet-derived growth factor(PDGF) plays an important role in stimulating myofibroblasts and regulating synthesis of extracellular matrix in renal interstitial proliferation and fibrosis. This study was designed to investigate the relationship between unilateral ureteral obstruction and PDGF expression in tubulointerstitial fibrosis of the kidney. Eleven adult male Spraugue-Dawley rats were carried out unilateral ureteral ligation and sham operation. After 14 days, control kidney, UUO kidney and intact opposite(IO) kidney were harvested. Tissue fibrosis was quantified morphologically using the point detection method after Masson-Trichrome stain. Expression of PDGF-A and B was determined by immunohistochemical staining, RT-PCR and Western blot assay. Results were as follows: 1) UUO and IO group resulted in reduced kidney weight compared with control group(p<0.05). 2) Collagen deposition was increased in the renal cortex of UUO group(p<0.05). 3) PDGF-A and B mRNA expression was increased significantly compared with control and IO group(p< 0.05). 4) PDGF-A and B protein expression were increased in UUO and IO group(p<0.05). 5) On the immunohistochemical staining for PDGF- A and B, staining intensity was increased significantly at the renal cortex, interstitium and tubular epithelial cells in the UUO group. This results indicated that PDGF-A and B plays important role in tubulointerstitial fibrosis developed after unilateral ureteral obstruction and compensatory fibroproliferative growth in contralateral kidney.