Transforming growth factor-beta 1 enhances discharge activity of cortical neurons

Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types involved.Voltage-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related diseases.However,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain unclear.In this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from mice.We found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 expression.Increased VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and Jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical neurons.These findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological conditions.Thus,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system.

Role of transforming growth factor-βin peripheral nerve regeneration

Injuries caused by trauma and neurodegenerative diseases can damage the peripheral nervous system and cause functional deficits.Unlike in the central nervous system,damaged axons in peripheral nerves can be induced to regenerate in response to intrinsic cues after reprogramming or in a growth-promoting microenvironment created by Schwann cells.However,axon regeneration and repair do not automatically result in the restoration of function,which is the ultimate therapeutic goal but also a major clinical challenge.Transforming growth factor(TGF)is a multifunctional cytokine that regulates various biological processes including tissue repair,embryo development,and cell growth and differentiation.There is accumulating evidence that TGF-βfamily proteins participate in peripheral nerve repair through various factors and signaling pathways by regulating the growth and transformation of Schwann cells;recruiting specific immune cells;controlling the permeability of the blood-nerve barrier,thereby stimulating axon growth;and inhibiting remyelination of regenerated axons.TGF-βhas been applied to the treatment of peripheral nerve injury in animal models.In this context,we review the functions of TGF-βin peripheral nerve regeneration and potential clinical applications.

Transforming growth factor-β1 and vascular endothelial growth factor levels in senile acute myeloid leukemia and correlation with prognosis

BACKGROUND Acute myeloid leukemia(AML)is a disease in which immature hematopoietic cells accumulate in the bone marrow and continuously expand,inhibiting hematopoiesis.The treatment and prognosis of this disease have always been unsatisfactory.AIM To investigate the correlation between vascular endothelial growth factor(VEGF)and transforming growth factor-β1(TGFβ1)expression and prognosis in older adults with AML.METHODS This study enrolled 80 patients with AML(AML group),including 36 with complete response(AML-CR),23 with partial response(AML-PR),and 21 with no response(AML-NR).The expression levels of VEGF and TGFβ1 were detected by reverse transcription polymerase chain reaction in bone marrow mononuclear cells isolated from 56 healthy controls.Kaplan-Meier analysis was performed to assess overall survival(OS)and progression-or disease-free survival(DFS).Prognostic risk factors were analyzed using a Cox proportional hazards model.RESULTS The AML group showed a VEGF level of 2.68±0.16.VEGF expression was lower in patients with AML-CR than those with AML-PR or AML-NR(P<0.05).TGFβ1 expression in the AML group was 0.33±0.05.Patients with AML-CR showed a higher TGFβ1 expression than those with AML-PR or AML-NR(P<0.05).VEGF and TGFβ1 expression in patients with AML was significantly correlated with the counts of leukocytes,platelets,hemoglobin,and peripheral blood immature cells(P<0.05);Kaplan-Meier survival analysis revealed that patients with high TGFβ1 expression had better OS and DFS than those with low TGFβ1 expression(P<0.05),whereas patients with low VEGF levels showed better OS and DFS than those with high VEGF levels(P<0.05).VEGF,TGFβ1,and platelet count were identified by the Cox proportional hazards model as independent risk factors for OS(P<0.05),while VEGF,TGFβ1,and white blood cell count were independent risk factors for DFS(P<0.05).CONCLUSION Decreased VEGF expression and increased TGFβ1 expression in patients with AML provide valuable references for determining and individualizing clinical treatment strategies.

Roles of transforming growth factor-βsignaling in liver disease

In this editorial we expand the discussion on the article by Zhang et al published in the recent issue of the World Journal of Hepatology.We focus on the diagnostic and therapeutic targets identified on the basis of the current understanding of the molecular mechanisms of liver disease.Transforming growth factor-β(TGF-β)belongs to a structurally related cytokine super family.The family members display different time-and tissue-specific expression patterns associated with autoimmunity,inflammation,fibrosis,and tumorigenesis;and,they participate in the pathogenesis of many diseases.TGF-βand its related signaling pathways have been shown to participate in the progression of liver diseases,such as injury,inflammation,fibrosis,cirrhosis,and cancer.The often studied TGF-β/Smad signaling pathway has been shown to promote or inhibit liver fibrosis under different circumstances.Similarly,the early immature TGF-βmolecule functions as a tumor suppressor,inducing apoptosis;but,its interaction with the mitogenic molecule epidermal growth factor alters this effect,activating anti-apoptotic signals that promote liver cancer development.Overall,TGF-βsignaling displays contradictory effects in different liver disease stages.Therefore,the use of TGF-βand related signaling pathway molecules for diagnosis and treatment of liver diseases remains a challenge and needs further study.In this editorial,we aim to review the evidence for the use of TGF-βsignaling pathway molecules as diagnostic or therapeutic targets for different liver disease stages.

Effect of intestinal ischemia-reperfusion on expressions of endogenous basic fibroblast growth factor and transforming growth factor β in lung and its relation with lung repair

AIM To study the changes of endogenoustransforming growth factor β(TGFβ)and basicfibroblast growth factor(bFGF)in lung followingintestinal ischemia and reperfusion injury andtheir effects on lung injury and repair.METHODS Sixty Wistar rats were divided intofive groups,which underwent sham-operation,ischemia(45 minutes),and reperfusion(6,24and 48 hours,respectively)after ischemia(45minutes).Immunohistochemical method wasused to observe the localization and amounts ofboth growth factors.RESULTS Positive signals of both growthfactors could be found in normal lung,mainly inalveolar cells and endothelial cells of vein.Afterischemia and reperfusion insult,expressions ofboth growth factors were increased and theiramounts at 6 hours were larger than those ofnormal control or of 24 and 48 hours after insult.CONCLUSION The endogenous bFGF and TGF βexpression appears to be up-regulated in thelung following intestinal ischemia andreperfusion,suggesting that both growth factorsmay be involved in the process of lung injury andrepair.

Stage-specific localization of transforming growth factor β1 and β3 and their receptors during spermatogenesis in men

Aim: To investigate the stage-specific localization of transforming growth factor (TGF) β1 and β3 during spermatogenesis in adult human testis. Methods: The localization of TGFβ1 and β3 was investigated by immunohis tochemical staining method employing specific polyclonal antibodies. Results: Both TGFβ1 and β3 and their recep tors were preponderant in the Leydig celis. TGFβ1 could not be detected in the seminiferous tubules. TGFβ3 and TGFβ-Receptor (R) I were mainly seen in the elongated spermatids, while TGFβ-RⅡ in the pachytene spermatocytes and weak in the spermatogonia, spermatids and Sertoli celis. Only TGFβ-RⅡ was detected in the Sertoli celis. TGFβ3, TGFβ-RⅠ and TGFβ-RⅡ showed a staining pattern dependent upon the stages of the seminiferous epithelium cycle. Conclusion: TGFβ isoforms and their receptors are present in the somatic and germ celis of the adult human testis, suggesting their involvement in the regulation of spermatogenesis.

Transforming growth factor-β and fibrosis

Transforming growth factor-β （TGF-β）, a prototype of multifunctional cytokine, is a key regulator of extracellular matrix （ECM） assembly and remodeling. Specifically, TGF-β isoforms have the ability to induce the expression of ECM proteins in mesenchymal cells, and to stimulate the production of protease inhibitors that prevent enzymatic breakdown of the ECM. Elevated TGF-β expression in affected organs, and subsequent deregulation of TGF-β functions, correlates with the abnormal connective tissue deposition observed during the onset of fibrotic diseases. During the last few years, tremendous progress has been made in the understanding of the molecular aspects of intracellular signaling downstream of the TGF-β receptors. In particular, Smad proteins, TGF-β receptor kinase substrates that translocate into the cell nucleus to act as transcription factors, have been studied extensively. The role of Smad3 in the transcriptional regulation of type I collagen gene expression and in the development of fibrosis, demonstrated both/n vitro and in animal models with a targeted deletion of Smad3, is of critical importance because it may lead to novel therapeutic strategies against these diseases. This review focuses on the mechanisms underlying Smad modulation of fibrillar collagen expression and how it relates to fibrotic processes.

Effect of matrine on transforming growth factor β1 and hepatocyte growth factor in rat liver fibrosis model

Objective:To observe the preventive and control effect of matrine on transforming growth factor(TCF- β1) and hepatocyte.growth factor(HCF) of liver fibrosis tissue in rals.Methods:A total of48 SD rats were randomly divided into A,B,C,D groups with 12 in each,group A as the normal control group and groups B.C,D as liver fibrosis models using composite modulus method with carbon tetrachloride(CCL_4).Group B was the model group,group C adopted γ— interferon lavage therapy in the second day of modeling,and group D adopted matrine lavage treatment,at 4 and8 weeks after treatment.Six rats were executed for detection of TGF- β1 and HGF,liver tissue histology and comparison fibrosis degree changes of rat liver tissue between groups.Results:Croups B,C,D showed a more significantly increased TCF- β1 at each time point compared with group A(P<0.05);Group B showed a more significantly increased TGF- β1 than groups C and D at weeks 4 and 8(P<0.05);group D showed a lowest level of TGF-β1,followed by groups C and B.HGF of group B decreased more significantly than A group at weeks 4 and 8(P<0.05);HGF of groups C and D was significantly elevated at 4 and 8 weeks than groups A and B(P<0.05),in which the group D showed the highest level of HGF.According to tissue histologic observation,rat liver tissue structure of group A was clear and normal,tissue structure of group B was destroyed with obvious fibrous tissue hyperplasia and fatty change of hepatic cells;groups C and D showed a slighter liver tissue damage,cell necrosis and connective tissue hyperplasia in collect abbacy than group B with a trend of obvious improvement.Conclusions:Matrine can reduce TGF- β1expression and enhance the activity of HGF,so as to realize the inhibition effect on liver fibrosis in rats.

Vascular endothelial growth factor A, secreted in response to transforming growth factor-β1 under hypoxic conditions, induces autocrine effects on migration of prostate cancer cells

Hypoxia and transforming growth factor-β1 （TGF-β1） increase vascular endothelial growth factor A （VEGFA） expression in a number of malignancies. This effect of hypoxia and TGF-β1 might be responsible for tumor progression and metastasis of advanced prostate cancer. In the present study, TGF-β1 was shown to induce VEGFA165 secretion from both normal cell lines （HPV7 and RWPE1） and prostate cancer cell lines （DU 145 and PC3）. Conversely, hypoxia-stimulated VEGFA165 secretion was observed only in prostate cancer cell lines. Hypoxia induced TGF-β1 expression in PC3 prostate cancer cells, and the TGF-β1 type I receptor （ALK5） kinase inhibitor partially blocked hypoxia-mediated VEGFA16s secretion. This effect of hypoxia provides a novel mechanism to increase VEGFA expression in prostate cancer cells. Although autocrine signaling of VEGFA has been implicated in prostate cancer progression and metastasis, the associated mechanism is poorly characterized. VEGFA activity is mediated via VEGF receptor （VEGFR） 1 （Fit-l） and 2 （FIk-I/KDR）. Whereas VEGFR-1 mRNA was detected in normal prostate epithelial cells, VEGFR-2 mRNA and VEGFR protein were expressed only in PC3 cells. VEGFA165 treatment induced phosphorylation of extracellular signal-regulated kinase 1/2 （ERKI/2） in PC3 cells but not in HPV7 cells, suggesting that the autocrine function of VEGFA may be uniquely associated with prostate cancer. Activation of VEGFR-2 by VEGFA165 was shown to enhance migration of PC3 cells. A similar effect was also observed with endogenous VEGFA induced by TGF-β1 and hypoxia. These findings illustrate that an autocrine loop of VEGFA via VEGFR-2 is critical for the tumorigenic effects of TGF-β1 and hypoxia on metastatic prostate cancers.

Organ fibrosis inhibited by blocking transforming growth factor-β signaling via peroxisome proliferator-activated receptor γ agonists

BACKGROUND:Organ fibrosis has been viewed as one of the major medical problems, which can lead to progressive dysfunction of the liver, lung, kidney, skin, heart, and eventually death of patients. Fibrosis is initiated by a variety of pathological, physiological, biochemical, and physical factors. Regardless of their different etiologies, they all share a common pathogenetic process: excessive activation of the key profibrotic cytokine, transforming growth factor-β (TGF-β). Peroxisome proliferator-activated receptor γ (PPARγ), a ligand-activated transcription factor of the nuclear receptor superfamily, has received particular attention in recent years, because the activation of PPARγ by both natural and synthetic agonists could effectively inhibit TGF-β-induced profibrotic effects in many organs. DATA SOURCES: The English-language medical databases, PubMed, Elsevier and SpringerLink were searched for articles on PPARγ, TGF-β, and fibrosis, and related topics. RESULTS: TGF-β is recognized as a key profibrotic cytokine. Excessive activation of TGF-β increases synthesis of extracellular matrix proteins and decreases their degradation, associated with a gradual destruction of normal tissue architecture and function, whereas PPARγ agonists inhibit TGF-β signal transduction and are effective antifibrogenic agents in many organs including the liver, lung, kidney, skin and heart. CONCLUSIONS: The main antifibrotic activity of PPARγ agonists is to suppress the TGF-β signaling pathway by so-called PPARγ-dependent effect. In addition, PPARγ agonists, especially 15d-PGJ2, also exert potentially antifibrotic activity independent of PPARγ activation. TGF-β1/Smads signaling not only plays many essential roles in multiple developmental processes, butalso forms cross-talk networks with other signal pathways, and their inhibition by PPARγ agonists certainly affects the cytokine networks and causes non-suspected side-effects. Anti-TGF-β therapies with PPARγ agonists may have to be carefully tailored to be tissue-and target gene-specific to minimize side-effects, indicating a great challenge to the medical research at present.

Expression of transforming growth factors in hepatocellular carcinoma and its relations with clinicopathological parameters and prognosis

BACKGROUND: Transforming growth factors (TGF)-beta 1, TGF-beta R2 and Smad4 belong to the TGF family, and play important roles in carcinogenesis and the development of carcinoma, especially hepatocellular carcinoma (HCC). TGF-beta 1 is a multipotent polypeptide, which inhibits the growth of epithelial cells including hepatoma cell lines and hepatocytes by inducing apoptosis. TGF-beta R2 forms a heterodimeric complex upon binding to TGF-beta, and then generates the first step in the signal transduction pathway leading to growth inhibition in coordination with the type I receptor. Smad4 protein is an important mediator in the TGF-beta signaling pathway, and negatively regulates the growth of epithelial cells. This study aimed to detect the expression of TGF-beta 1, TGF-beta R2 and Smad4 in HCCs and their adjacent normal tissues, while assessing its relations with the clinicopathological parameters of HCC. METHODS: Forty-seven HCC specimens and their adjacent normal tissues were obtained surgically at the Affiliated Hospital of Medical College, Qingdao University. The expression of TGF-beta 1, TGF-beta R2 and Smad4 was separately detected by immunohistochemistry in all HCC specimens and their adjacent normal tissues, and its relations with the clinicopathological parameters of HCC were assessed. RESULTS: The positive expression of TGF-beta 1 was 72.34% in the HCC specimens, which was higher than that in the adjacent normal tissues (P < 0.001). The positive expression of Smad4 and TGF-beta R2 was 34.04% and 59.57% respectively in the carcinoma specimens. The expression of TGF-beta 1, TGF-beta R2 and Smad4 was significantly higher in groups with a tumor embolus of the portal vein, integrity of the amicula, and Edmondson's III-IV than that in other groups, but it was not related to tumor size (P < 0.05). CONCLUSIONS: TGF-beta 1 may play an important role in the occurrence and development of HCC. Combined detection of TGF-beta 1, TGF-beta R2 and Smad4 may be useful for the determination of the degree of malignancy and the prognosis of HCC.

Roles of Smad3 and Smad7 in rat pancreatic stellate cells activated by transforming growth factor-beta 1

BACKGROUND: Pancreatic stellate cells (PSCs) play a major role in promoting pancreatic fibrosis. Transforming growth factor beta 1 (TGF-beta 1) is a critical mediator of this process. This study aimed to determine the expression of the Smad3 and Smad7 genes in the process of PSC activation, and explore the mechanisms of chronic pancreatitis. METHODS: The expressions of Smad3 and Smad7 in PSCs before and after TGF-beta 1 treatment were detected by reverse transcription-polymerase chain reaction and Western blotting analysis. Smad3 expression was detected in PSCs after treatment with 5 ng/ml of TGF-beta 1 for 24 hours. RESULTS: Smad7 expression was decreased in TGF-beta 1 -activated PSCs (P<0.05) in a dose-dependent manner. When TGF-beta 1 concentration reached 10 ng/ml, the expression of p-Smad3, Smad3, and Smad7 was inhibited (P<0.05). CONCLUSIONS: TGF-beta 1 promotes the expression of Smad3 and inhibits the expression of Smad7 during the activation of PSCs. In contrast, high-dose TGF-beta 1 downregulates the expression of Smad3 in completely activated PSCs.

Transforming growth factor -β neutralizing antibodies inhibit subretinal fibrosis in a mouse model

AIM:To determine the involvement of the transforming growth factor(TGF)-β with the development of experimental subretinal fibrosis in a mouse model.· METHODS:Subretinal fibrosis was induced by subretinal injection of macrophage-rich peritoneal exudate cells(PECs) and the local expression of TGF-β isoforms was assessed by quantitative real-time reverse transcription-polymerase chain reaction(RT-PCR) and enzyme-linked immunosorbent assay(ELISA) at various time points.In addition,we investigated the effect of TFG-β-neutralizing antibodies(TGF-β NAb) on subretinal fibrosis development.· RESULTS:TGF-β1 and TGF-β2 mRNA level was significantly elevated at day 2 after subretinal fibrosis induction and increased further to 5 and 6.5-fold respectively at day 5,reaching the peak.TGF-β3 mRNA was not detected in the present study.The result of ELSIA showed that active TGF-β1 and TGF-β2 levels were upregulated to 10-fold approximately,while total TGF-β1 and TGF-β2 levels were even upregulated more than 10-fold and more than 20-fold respectively in subretinal fibrosis mice in comparison with na?觙ve mice at day 5.TGF-β NAb resulted in a reduced subretinal fibrosis areas by 65% compared to animals from control group at day 7.· CONCLUSION:Our results indicate that TGF-β signaling may contribute to the pathogenesis of subretinal fibrogenesis and TGF-β inhibition may provide an effective,novel treatment of advanced and late-stage neovascular age-related macular degeneration.·

Total flavone of Abelmoschus manihot suppresses epithelial-mesenchymal transition via interfering transforming growth factor-β1 signaling in Crohn's disease intestinal fibrosis

AIM To explore the role and mechanism of total flavone of Abelmoschus manihot(TFA) on epithelial-mesenchymal transition(EMT) progress of Crohn's disease(CD) intestinal fibrosis.METHODS First,CCK-8 assay was performed to assess TFA on the viability of intestinal epithelial(IEC-6) cells and select the optimal concentrations of TFA for our further studies.Then cell morphology,wound healing and transwell assays were performed to examine the effect of TFA on morphology,migration and invasion of IEC-6 cells treated with TGF-β1.In addition,immunofluorescence,real-time PCR analysis(q RT-PCR) and western blotting assays were carried out to detect the impact of TFA on EMT progress.Moreover,western blotting assay was performed to evaluate the function of TFA on the Smad and MAPK signaling pathways.Further,the role of co-treatment of TFA and si-Smad or MAPK inhibitors has been examined by q RTPCR,western blotting,morphology,wound healing andtranswell assays.RESULTS In this study,TFA promoted transforming growth factor-β1(TGF-β1)-induced(IEC-6) morphological change,migration and invasion,and increased the expression of epithelial markers and reduced the levels of mesenchymal markers,along with the inactivation of Smad and MAPK signaling pathways.Moreover,we revealed that si-Smad and MAPK inhibitors effectively attenuated TGF-β1-induced EMT in IEC-6 cells.Importantly,co-treatment of TFA and si-Smad or MAPK inhibitors had better inhibitory effects on TGF-β1-induced EMT in IEC-6 cells than either one of them.CONCLUSION These findings could provide new insight into the molecular mechanisms of TFA on TGF-β1-induced EMT in IEC-6 cells and TFA is expected to advance as a new therapy to treat CD intestinal fibrosis.

Transforming growth factor beta 1, a cytokine with regenerative functions

We review the biology and role of transforming growth factor beta 1 （TGF-β1） in peripheral nerve injury and regeneration, as it relates to injuries to large nerve trunks （i.e., sciatic nerve, brachial plexus）, which often leads to suboptimal functional recovery. Experimental studies have suggested that the reason for the lack of functional recovery resides in the lack of sufficient mature axons reaching their targets, which is a result of the loss of the growth-supportive environment provided by the Schwann cells in the distal stump of injured nerves. Using an established chronic nerve injury and delayed repair animal model that accu- rately mimics chronic nerve injuries in humans, we summarize our key findings as well as others to better understand the pathophysiology of poor functional recovery. We demonstrated that 6 month TGF-β1 treat- ment for chronic nerve injury significantly improved Schwann cell capacity to support axonal regeneration. When combined with forskolin, the effect was additive, as evidenced by a near doubling of regenerated axons proximal to the repair site. We showed that in vivo application of TGF-β1 and forskolin directly onto chronically injured nerves reactivated chronically denervated Schwann cells, induced their proliferation, and upregulated the expression of regeneration-associated proteins. The effect of TGF-β1 and forskolin on old nerve injuries is quite impressive and the treatment regiment appears to mediate a growth-supportive milieu in the injured peripheral nerves. In summary, TGF-β1 and forskolin treatment reactivates chronical- ly denervated Schwann cells and could potentially be used to extend and prolong the regenerative responses to promote axonal regeneration.

Effects of RNA interference targeting transforming growth factor-beta 1 on immune hepatic fibrosis induced by Concanavalin A in mice

BACKGROUND: Previous studies have shown that transforming growth factor-beta 1 (TGF-beta 1) is the most potent means of stimulating liver fibrogenesis by myofibroblast-like cells derived from hepatic stellate cells. Thus, TGF-beta 1 could be a target for treating hepatic fibrosis. This study aimed to investigate the inhibitory effects of specific TGF-beta 1 small interference RNA (siRNA) on immune hepatic fibrosis induced by Concanavalin A (Con A) in mice. METHODS: Three short hairpin RNAs targeting different positions of TGF-beta 1 were designed and cloned to the plasmid pGenesil-1 to obtain three recombinant expression vectors (pGenesil-TGF-beta 1-ml, pGenesil-TGF-beta 1-m2 and pGenesil-TGF-beta 1-m3). Thirty male Kunming mice were randomly divided into 6 groups: normal, model, control, and three treatment groups. The immune hepatic fibrosis models were constructed by injecting Con A via the tail vein at 8 mg/kg per week for 6 weeks. At weeks 2, 4 and 6, pGenesil-TGF-beta 1-ml, pGenesil-TGF-beta 1-m2 or pGenesi1-TGF-beta 1-m3 was injected by a hydrodynamics-based transfection method via the tail vein at 0.8 ml/10 g within 24 hours after injection of Con A in each of the three treatment groups. The mice in the control group were injected with control plasmid pGenesil-HK at the same dose. All mice were sacrificed at week 7. The levels of hydroxyproline in liver tissue were determined by biochemistry. Liver histopathology was assessed by Van Gieson staining. The expression levels and localization of TGF-beta 1, Smad3, and Smad7 in liver tissue were detected by immunohistochemistry. The expression of TGF-beta 1, Smad3, Smad7 and alpha-smooth muscle actin (alpha-SMA) mRNAs in the liver were assessed by semi-quantitative RT-PCR. RESULTS: The levels of hydroxyproline in the liver tissue of the treatment groups were lower than those of the model group (P<0.01). Histopathologic assay showed that liver fibrogenesis was clearly improved in the treatment groups compared with the model group. The expression levels of TGF-beta 1 and Smad3 of liver tissue were also markedly lower in the treatment groups than in the model group (P<0.01), while the levels of Smad7 were higher in the treatment groups than in the model group (P<0.01). RT-PCR further showed that the expression of TGF-beta 1, Smad3 and alpha-SMA mRNA was significantly inhibited in the treatment groups compared with the model group, while the levels of Smad7 were increased. There was no difference in the above parameters among the three treatment groups or between the control and model groups (P>0.05), but the inhibitory effect of pGenesil-TGF-beta 1-ml was the highest among the treatment groups. CONCLUSIONS: Specific siRNA targeting of TGF-beta 1 markedly inhibited the fibrogenesis of immune hepatic fibrosis induced by Con A in mice. The anti-fibrosis mechanisms of siRNAs may be associated with the down-regulation of TGF-beta 1, Smad3 and alpha-SMA expression and up-regulation of Smad7 expression in liver tissue, which resulted in suppressing the activation of hepatic stellate cells. (Hepatobiliary Pancreat Dis Int 2009; 8: 300-308)

Effects of interferon-alpha on expression of hepatic stellate cell and transforming growth factor-pi and a-smooth muscle actin in rats with hepatic fibrosis

AIM:To investigate the effect of interferon-a (IFN-α) on preventing or reversing hepatic fibrosis in rat experimental model induced by CCI4. METHODS: One hundred and ten Sprague-Dawley rats were divided into five groups: group A (normal controls, n = 18), group B (fibrotic model controls, n = 22), group C (IFN-α prevention, n = 22) initially treated with intramuscular injection of IFN-a in saline daily at the doses of 1× 105 U for 6 wk, group D (IFN-a treatment, n = 24) treated with intra-muscular injection of IFN-a in saline daily at the doses of 1×105 U for 6 wk after the first 6 wk, group E (0.9% sodium chloride treatment control, n = 24) treated with intra-muscular injection of 0.01 mL/kg daily for 6 wk after the first 6 wk. At the end of the experiment, all rats of each group were killed. Samples of the liver obtained by biopsy were subjected to histological, immunohistochemical and electron microscopic studies for the expressions of transforming growth factor-pi (TGF- μ41) and α-smooth muscle actin (α-SMA). RESULTS: The expressions of TGF-pl, the number of activated hepatic stellate cells and a-SMA in hepatic tissue of group C were significantly less than those of group B (P<0.01). The degree of fibrosis score in group B was also significantly less than that of group C under light microscope (P<0.01). CONCLUSION: IFN-a can inhibit the production of TGF-pl, decrease HSC activation and stimulate its apoptosis.

Platelet-rich plasma increases transforming growth factor-beta1 expression at graft-host interface following autologous osteochondral transplantation in a rabbit model

AIM: To explore the effect of platelet-rich plasma on protein expression patterns of transforming growth factor-beta1(TGF-β1) in cartilage following autologous osteochondral transplantation(AOT) in a rabbit knee cartilage defect model.METHODS: Twelve New Zealand white rabbits received bilateral AOT. In each rabbit, one knee was randomized to receive an autologous platelet rich plasma(PRP) injection and the contralateral knee received saline injection. Rabbits were euthanized at 3, 6 and 12 wk post-operatively. Articular cartilage sections were stained with TGF-β1 antibody. Histological regions of interest(ROI)(left, right and center of the autologous grafts interfaces) were evaluated using Meta Morph. Percentage of chondrocytes positive for TGF-β1 was then assessed.RESULTS: Percentage of chondrocytes positive for TGF-β1 was higher in PRP treated knees for selected ROIs(left; P = 0.03, center; P = 0.05) compared to control and was also higher in the PRP group at each post-operative time point(P = 6.6 × 10^(-4), 3.1 × 10^(-4) and 7.3 × 10^(-3) for 3, 6 and 12 wk, respectively). TGF-β1 expression was higher in chondrocytes of PRP-treated knees(36% ± 29% vs 15% ± 18%)(P = 1.8 × 10^(-6)) overall for each post-operative time point and ROI. CONCLUSION: Articular cartilage of rabbits treated with AOT and PRP exhibit increased TGF-β1 expression compared to those treated with AOT and saline. Our findings suggest that adjunctive PRP may increase TGF-β1 expression, which may play a role in the chondrogenic effect of PRP in vivo.

Transforming growth factor-β and peripheral regulatory cells are negatively correlated with the overall survival of hepatocellular carcinoma

AIM To understand the cellular and molecular changes inperipheral blood that can lead to the development of hepatocellular carcinoma(HCC) and provide new methods for its diagnosis and treatment.METHODS Peripheral blood mononuclear cells were isolated from the peripheral blood of HCC patients and normal controls and then analyzed by flow cytometry. The percentage of transforming growth factor-β(TGF-β)+ regulatory cells(Tregs) in the peripheral blood was measured, and the expression of TGF-β was also determined. Then, the relationship between the changes and the 5-year survival of patients was analyzed. In addition, recombinant human TGF-β(rh TGF-β) and recombinant human interleukin-6 were added to stimulate the cultured cells, and their effects on HCC were evaluated.RESULTS The expression of TGF-β and the percentage of TGF-β+ Tregs in the peripheral blood of HCC patients increased significantly compared with normal controls. Compared with the low TGF-β expression group, the high TGF-β expression group had a significantly lower 5-year survival rate, and the same result was found in the two TGF-β+ Treg groups, suggesting that TGF-β and TGF-β+ Tregs were negatively correlated with the overall survival of the patients. In addition, rh TGF-β promoted the growth of tumor cells and induced high expression levels of IL-6, which further promoted tumor proliferation.CONCLUSION The results showed that TGF-β may promote tumor growth and proliferation by inducing the production of IL-6, and TGF-β and TGF-β+ Tregs may serve as new markers for predicting a poor prognosis in HCC.

Celastrol inhibits migration, proliferation and transforming growth factor-β2-induced epithelial-mesenchymal transition in lens epithelial cells

AIM: To investigate the mechanism of celastrol in inhibiting lens epithelial cells(LECs) fibrosis, which is the pathological basis of cataract.METHODS: Human LEC line SRA01/04 was treated with celastrol and transforming growth factor-β2(TGF-β2). Wound-healing assay, proliferation assay, flow cytometry, real-time polymerase chain reaction(PCR), Western blot and immunocytochemical staining were used to detect the pathological changes of celastrol on LECs. Then, we cultured Sprague-Dawley rat lens in medium as a semi-in vivo model to find the function of celastrol further.RESULTS: We found that celastrol inhibited the migration of LECs, as well as proliferation(P<0.05). In addition, it induced the G2/M phase arrest by cell cyclerelated proteins(P<0.01). Moreover, celastrol inhibited epithelial-mesenchymal transition(EMT) by the blockade of TGF-β/Smad and Jagged/Notch signaling pathways.CONCLUSION: Our study demonstrates that celastrol could inhibit TGF-β2-induced lens fibrosis and raises the possibility that celastrol could be a potential novel drug in prevention and treatment of fibrotic cataract.