Hepatocyte Growth Factor Gene Therapy Research Articles

Hepatocyte growth factor gene therapy enhances infiltration of macrophages and may induce kidney repair in db/db mice as a model of diabetes

Aims/hypothesisWe previously demonstrated hepatocyte growth factor (HGF) gene therapy was able to induce regression of glomerulosclerosis in diabetic nephropathy through local reparative mechanisms. The aim of this study was to test whether bone-marow-derived cells are also involved in this HGF-induced reparative process.MethodsWe have created chimeric db/db mice as a model of diabetes that produce enhanced green fluorescent protein (EGFP) in bone marrow cells. We performed treatment with HGF gene therapy either alone or in combination with granulocyte-colony stimulating factor, in order to induce mobilisation of haematopoietic stem cells in these diabetic and chimeric animals.ResultsWe find HGF gene therapy enhances renal expression of stromal-cell-derived factor-1 and is subsequently associated with an increased number of bone-marrow-derived cells getting into the injured kidneys. These cells are mainly monocyte-derived macrophages, which may contribute to the renal tissue repair and regeneration consistently observed in our model. Finally, HGF gene therapy is associated with the presence of a small number of Bowman’s capsule parietal epithelial cells producing EGFP, suggesting they are fused with bone-marrow-derived cells and are contributing to podocyte repopulation.Conclusions/interpretationAltogether, our findings provide new evidence about the therapeutic role of HGF and open new opportunities for inducing renal regeneration in diabetic nephropathy.

Plasmid DNA-based Gene Transfer with Ultrasound and Microbubbles

Gene therapy offers a novel approach for the prevention and treatment of a variety of diseases, but it is not yet a common option in the real world because of various problems. Viral vectors show high efficiency of gene transfer, but they have some problems with toxicity and immunity. On the other hand, plasmid DNA-based gene transfer is very safe, but its efficiency is relatively low. Especially, plasmid DNA gene therapy is used for cardiovascular disease because plasmid DNA transfer is possible for cardiac or skeletal muscle. Clinical angiogenic gene therapy using plasmid DNA gene transfer has been attempted in patients with peripheral artery disease, but a Phase III clinical trial did not show sufficient efficiency. Recently, a Phase III clinical trial of hepatocyte growth factor gene therapy in peripheral artery disease (PAD) showed improvement of ischemic ulcers, but it could not salvage limbs from amputation. In addition, a Phase I/II clinical study of fibroblast growth factor gene therapy in PAD extended amputation-free survival, but it seemed to fail in Phase III. In this situation, we and others have developed plasmid DNA-based gene transfer using ultrasound with microbubbles to enhance its efficiency while maintaining safety. Ultrasound-mediated gene transfer has been reported to augment the gene transfer efficiency and select the target organ using cationic microbubble phospholipids which bind negatively charged DNA. Ultrasound with microbubblesis likely to create new therapeutic options inavariety of diseases.

Long-term effects of hepatocyte growth factor gene therapy in rat myocardial infarct model

We investigated the long-term effects of human hepatocyte growth factor (HGF) gene therapy in a rat myocardial infarct model. Treatment adenovirus coexpressing the HGF therapeutic gene and the human sodium/iodide symporter (NIS) reporter gene or control adenovirus expressing the NIS gene alone were injected directly into the infarct border zone immediately after permanent coronary ligation in rats (n=6 each). A uniform disease state was confirmed in the acute phase in terms of impaired left ventricular (LV) function by cine magnetic resonance imaging (MRI), large infarct extent by (99m)Tc-tetrofosmin single-photon emission computed tomography (SPECT) and successful gene transfer and expression by (99m)TcO(4)(-) SPECT. After a 10-week follow-up, repeated cine MRI demonstrated no significant difference in the LV ejection fraction between the time points or groups, but a significantly increased end-diastolic volume from the acute to the chronic phase without a significant difference between the groups. Capillary density was significantly higher in the treatment group, whereas arteriole density remained unchanged. Two-photon excitation fluorescence microscopy revealed extremely thin capillaries (2-5 μm), and their irregular networks increased in the infarct border zone of the treated myocardium. Our results indicated that single HGF gene therapy alone induced an immature and irregular microvasculature.

Safety of Vascular Endothelial and Hepatocyte Growth Factor Gene Therapy in Patients with Critical Limb Ischemia

The present clinical trial analyzed the safety of gene therapy using plasmidial constructs expressing vascular endothelial and hepatocyte growth factors in patients with critical limb ischemia. The study included 43 patients: 29 in the treatment group and 14 allocated to the placebo group. The primary end points were the rate of major amputations and the clinical safety of the method. Secondary end points were improvement of pain at rest, walking ability and the ankle/brachial pressure index. The overall major amputation rate was 31.04% in the treatment group and 71.42% in the placebo group (p = 0.029). Pain at rest was improved in 65% of patients in the gene therapy group and in 7% in the placebo group (p = 0.0006). There were no significant adverse effects in the treatment group. Gene therapy with vascular endothelial and hepatocyte growth factors is therapeutically safe and reduces the rate of major amputations and relieves pain at rest in patients with critical limb ischemia.

Randomized, double-blind, placebo-controlled clinical trial of hepatocyte growth factor plasmid for critical limb ischemia

Hepatocyte growth factor (HGF) is a potent angiogenic factor. The efficacy and safety of intramuscular injection of a naked plasmid encoding human HGF gene (beperminogene perplasmid, Collategene) was investigated in patients with critical limb ischemia (CLI) in a multicenter, randomized, double-blind, placebo-controlled trial. The randomization ratio for plasmid to placebo was 2:1. Injection sites were selected in each patient limb based on angiographic findings. Placebo or plasmid was injected on days 0 and 28. Evaluation of efficacy was carried out after 12 weeks. The primary end point was the improvement of rest pain in patients without ulcers (Rutherford 4) or the reduction of ulcer size in patients with ulcer(s) (Rutherford 5). Secondary end points were ankle-brachial pressure index, amputation, and quality of life (QOL). Forty-four patients were treated, and we performed interim analysis of efficacy in 40 patients. The overall improvement rate of the primary end point was 70.4% (19/27) in HGF group and 30.8% (4/13) in placebo group, showing a significant difference (P=0.014). In Rutherford 5 patients, HGF achieved a significantly higher improvement rate (100% [11/11]) than placebo (40% [2/5]; P=0.018). HGF plasmid also improved QOL. There were no major safety problems. HGF gene therapy is safe and effective for CLI.

Synergistic effects of autologous cell and hepatocyte growth factor gene therapy for neovascularization in a murine model of hindlimb ischemia

Autologous cell implantation and angiogenic gene therapy have been evaluated in critical limb ischemic patients. Here, we compared the features of these strategies individually and in combination. C57BL/6J mice with ischemic hindlimbs were injected with adherent mononuclear cells (aMNCs) from bone marrow or adenovirus encoding the hepatocyte growth factor (HGF) gene (Ad-HGF). Under comparable angiogenic conditions, 10 x 10(5) aMNCs produced significantly higher amounts of VEGF and FGF-2 and stimulated the number of arterioles in ischemic muscle compared with 1 x 10(8) plaque-forming units (pfu) of Ad-HGF. Ad-HGF produced 10 times more HGF in ischemic muscle compared with aMNCs. Injection of 0.3 x 10(5) aMNCs previously transfected with Ad-HGF (aMNC/Ad-HGF) increased blood flow and elevated the numbers of capillaries and arterioles to levels comparable with that seen with 10 x 10(5) aMNCs or 1 x 10(8) pfu of Ad-HGF. Hypoxic conditions induced the apoptotic death of aMNCs. However, coincubation with HGF or aMNC/Ad-HGF protected cells against apoptosis. HGF stimulated the migration of aMNCs, and the migration capacity of the aMNC/Ad-HGF group was significantly higher than that in the aMNC/Ad-LacZ group. In conclusion, cell-based HGF gene therapy decreased the number of cells required for neovascularization. This strategy can be an effective angiogenic therapy.

HEPATOCYTE GROWTH FACTOR PLAYS A CRITICAL ROLE IN THE REGULATION OF CYTOKINE PRODUCTION AND INDUCTION OF ENDOTHELIAL PROGENITOR CELL MOBILIZATION: A PILOT GENE THERAPY STUDY IN PATIENTS WITH CORONARY HEART DISEASE

1. There is growing evidence of the beneficial effects of hepatocyte growth factor (HGF) in myocardial infarction, heart failure and occlusive peripheral arterial disease. The aim of the present study was to evaluate the effects of intracoronary administration of an adenovirus vector encoding the human HGF gene (Ad-HGF) on serum levels of cytokines and mobilization of CD34(+) and CD117(+) cells in patients with coronary heart disease. 2. Twenty-one patients with severe coronary artery disease were recruited to the study: 11 patients received both a stent and administration of Ad-HGF; the remaining 10 patients received a stent alone and served as the control group. Blood samples were obtained from the femoral vein before and then 6 and 24 h, 3 and 6 days and 2 weeks after treatment for the isolation of serum and peripheral blood mononuclear cells. Intracoronary administration of Ad-HGF in patients with coronary heart disease resulted in high levels of HGF gene expression, as well as its receptor c-met, compared with the control group, as demonstrated by real-time reverse transcription-polymerase chain reaction. In addition, serum levels of HGF, vascular endothelial growth factor, monocyte chemoattractant protein-1 and interleukin (IL)-10 were increased and serum levels of IL-8 were decreased in patients administered Ad-HGF compared with the control group. The percentage of CD34(+) and CD117(+) cells in the peripheral blood increased in patients administered Ad-HGF. 3. In conclusion, HGF gene therapy may play an important role in the regulation of cytokines and the induction of endothelial progenitor cell mobilization in patients with coronary heart disease.

Treating liver cirrhosis in dogs with hepatocyte growth factor gene therapy via the hepatic artery

Liver cirrhosis, an irreversible result of chronic liver disease, has had no effective therapy except liver transplantation. We previously reported successful therapy of liver cirrhosis in rats using the hepatocyte growth factor gene. We presently performed hepatocyte growth factor gene therapy in dogs with liver cirrhosis to examine the feasibility for clinical use. Liver cirrhosis was established in beagles by administrating dimethylnitrosamine. Naked human hepatocyte growth factor gene or naked LacZ gene was injected repeatedly into livers via the hepatic artery using a porter catheter in dogs with cirrhosis. Human hepatocyte growth factor gene expression was detected in livers by immunohistochemical staining and an enzyme-linked immunosorbent assay. Serum liver function test results improved with hepatocyte growth factor gene therapy, which also inhibited hepatic transforming growth factor-beta1expression and reversed fibrosis in cirrhotic liver, improving survival of the dogs. As naked hepatocyte growth factor gene therapy via the hepatic artery proved simple, safe, and effective in larger animals with cirrhosis, this therapy may be clinically applicable.

Tc-99m-MIBI scintigraphy in evaluating the effect of hepatocyte growth factor gene therapy for peripheral arteriosclerosis obliterans

We report an 81-year-old man with arteriosclerosis obliterans with sharp rest pain of the left lower leg below the knee that was resistant to conventional drug therapy. Gene therapy using hepatocyte growth factor (HGF) was performed, following which the symptoms remarkably improved. Magnetic resonance (MR) angiography did not detect any development of collateral vessels following gene therapy; however, technetium-99m-methoxyisobutylisonitrile (Tc-99m)-MIBI scintigraphy revealed the development of micro-circulation in the lower leg following HGF gene therapy. This is the first report on the usefulness of Tc-99m-MIBI scintigraphy to evaluate the effectiveness of HGF gene therapy for peripheral arteriosclerosis obliterans.

Hepatocyte growth factor gene transfer with naked plasmid DNA ameliorates dimethylnitrosamine‐induced liver fibrosis in rats

Hepatocyte growth factor (HGF) has various biological properties, including antifibrogenic activity. In the present study, we tested the efficacy of HGF gene therapy using naked plasmid DNA in dimethylnitrosamine (DMN)-induced liver fibrosis in a rat model. Naked plasmid DNA encoding human HGF was injected once, together with a hypertonic solution, into the hepatic artery after DMN treatment on three consecutive days per week for 3 weeks. Naked plasmid DNA encoding beta-galactosidase was injected similarly in the DMN-treated control rats. DMN treatment was continued once weekly after gene transfer for additional 3 weeks. The human HGF protein expression was detected in livers transfected with human HGF naked plasmid DNA, gradually decreasing by day 21. The expression of the endogenous rat HGF protein was also upregulated after human HGF gene transfer. Phosphorylation of c-Met, a HGF receptor, was detected only in livers transfected with human HGF plasmid DNA. Fibrosis was attenuated significantly in livers transfected with the human HGF plasmid. Attenuation wasaccompanied by decreased expression of alpha-smooth muscle actin. Increased portal vein pressure after treatment with DMN was suppressed significantly by HGF gene transfer. The upregulated hepatic protein expression of transforming growth factor-beta (TGF-beta) in response to DMN was markedly attenuated by HGF gene transfer accompanied by the increased protein expression for matrix metalloproteinases (MMP)-3 and -13. The hepatic arterial injection of human naked plasmid HGF DNA was effective in suppressing liver fibrosis induced in rats by DMN. The mechanisms by which HGF expression attenuated liver fibrosis may include the suppression of hepatic TGF-beta expression and the induction of MMP expression.

In Vivo Evidence of Enhancement of HGF-induced Angiogenesis by Fluvastatin

Currently, therapeutic angiogenesis using gene transfer of angiogenic growth factors has entered the realm of novel therapy for patients with critical limb ischemia. However, its clinical utility might be enhanced by combination with classical pharmacological approaches. Thus, in this study, we examined adjunctive therapy to enhance the angiogenic ef- fects of gene transfer, with HMG-CoA reductase inhibitors, statins, which have pleiotropic vascular-protective effects. Here, we evaluated the effects of a combination of hepatocyte growth factor (HGF) gene therapy with fluvastatin in a mouse hindlimb ischemia model. Hindlimb ischemia model mice were given a normal diet, high-cholesterol diet (HCD) or HCD with fluvastatin, after in- tramuscular injection of human HGF plasmid DNA. Intramuscular injection of HGF plasmid into ischemic limbs signifi- cantly increased blood flow and capillary density. However, HCD diminished the increase in blood flow and capillary density induced by HGF gene transfer. Administration of fluvastatin significantly attenuated the reduction in blood flow and decrease in capillary density, while it did not change the serum cholesterol level. Overall, these results demonstrated that fluvastatin significantly enhanced the increase in blood flow and capillary density induced by HGF gene transfer in a hindlimb ischemia mouse model with HCD, through a non-cholesterol-lowering effect. Clinical use of fluvastatin might be possible adjunctive therapy to enhance therapeutic angiogenesis.

HGF as a renotrophic and anti-fibrotic regulator in chronic renal disease

Hepatocyte growth factor (HGF) and Met/HGF receptor play roles in dynamic growth and morphogenesis during development and regeneration of organs, including the kidney. In the kidney, HGF targets different types of cells, while its biological actions depend on a target cell type. During the earlier stages of chronic renal failure, renal HGF expression increased, but in later stages HGF expression decreased, associated with manifestation of chronic renal failure. When anti-HGF IgG was administered into mice with chronic renal failure, renal dysfunction and fibrosis were accelerated, indicating a role of endogenous HGF to suppress chronic renal failure. For myofibroblasts, a key cell type in tissue fibrosis, HGF exerted biological activities, including (i) inhibition of growth, (ii) suppression of fibrogenic cytokine expression, and (iii) enhancement of matrix metalloproteinases involved in subsequent apoptosis. In models of glomerular and tubulo-interstitial fibrosis, administration of HGF or HGF gene therapy improved renal fibrosis and dysfunction. Since insufficient production of HGF is causative for renal fibrosis, supplementation with HGF represents a new approach to inhibit or improve chronic renal failure.

Adeno-associated virus vector-mediated production of hepatocyte growth factor attenuates liver fibrosis in mice

Adeno-associated virus (AAV) vectors can achieve long-term gene expression and are now feasible for use in human gene therapy. We constructed hepatocyte growth factor (HGF) expressing AAV (AAV5-HGF) and examined its effect in two mouse hepatic fibrosis models. A model of hepatic fibrosis was established by carbon tetrachloride (CCl(4)) administration in Balb/c mice. After the establishment of liver fibrosis, AAV5-HGF was injected once into the portal vein. Mice were killed 3, 6, 9, and 12 weeks after injection. Another model was established by bile duct ligation (BDL). Seven weeks after AAV5-HGF injection, mice underwent BDL, and were then killed 2 weeks after BDL. Mice that received AAV5-HGF achieved stable HGF expression both in the serum and liver for at least 12 weeks. In both models, significant improvement of the liver fibrosis was found in all mice receiving AAV5-HGF based on Azan-Mallory staining. Suppression of hepatic stellate cells (HSC) was confirmed by immunohistochemistry. Fibrogenic markers were significantly suppressed and collagenase activity increased in the livers of mice receiving AAV5-HGF. A single injection of AAV vector containing HGF gene achieved long-term expression of HGF and resulted in resolution of mouse liver fibrosis. HGF gene therapy mediated by AAV is feasible for the treatment of liver fibrosis.

In Vivo Hepatocyte Growth Factor Gene Transfer Reduces Myocardial Ischemia-Reperfusion Injury Through Its Multiple Actions

Background Hepatocyte growth factor (HGF) is reported to protect the heart against ischemia-reperfusion injury. However, whether in vivo adenovirus-mediated HGF gene transfer before ischemia is protective against ischemia-reperfusion and its precise mechanisms are still unknown. Methods and Results By using a rabbit model of ischemia-reperfusion injury, we demonstrate that HGF gene transfer is cardioprotective through its multiple beneficial actions, such as angiogenesis, Bcl-2 overexpression, and decreasing hydroxyl radicals, deoxyuride-5′-triphosphate biotin nick end labeling (TUNEL)-positive myocytes, and fibrotic area. After HGF gene transfer, the rabbits underwent 30 minutes of coronary occlusion and 30 minutes, 4 hours, 48 hours, and 14 days of reperfusion. The infarct size at 48 hours of reperfusion was significantly reduced in the HGF group (13.4% ± 2.3%) compared with that in the LacZ group (36.5% ± 2.0%) and saline group (40.3% ± 3.2%). At 14 days of reperfusion, HGF gene transfer improved left ventricular ejection fraction and fractional shortening, reduced the fibrotic area, and increased the capillary density in the risk area. At 4 hours of reperfusion, Bcl-2 protein was overexpressed and the incidence of TUNEL-positive myocytes was significantly decreased in the risk area in the HGF group compared with the LacZ and saline groups. The myocardial interstitial 2,5-dihydroxybenzoic acid level, an indicator of hydroxyl radical, increased during 30 minutes of ischemia and 30 minutes of reperfusion in the LacZ and saline groups, and was significantly inhibited in the HGF group. Conclusion HGF gene therapy may be a novel therapeutic strategy against unstable angina pectoris or severe angina pectoris, which may progress to acute myocardial infarction.

An hepatocyte growth factor gene therapy [AMG 0001]* appears to be efficacious for the treatment of patients with critical limb ischaemia,

An hepatocyte growth factor gene therapy [AMG 0001]* appears to be efficacious for the treatment of patients with critical limb ischaemia,

Hepatocyte growth factor promotes colonic epithelial regeneration via Akt signaling

Hepatocyte growth factor (HGF) can promote the regeneration of injured organs, including HGF gene therapy by electroporation (EP) for liver injury. In this study, we investigated the effect of HGF on dextran sulfate sodium-induced colitis and tried to clarify the regenerative mechanisms of colonic epithelial cells and the signaling pathway involved. Colitis was induced by dextran sulfate sodium in mice, together with HGF gene transfer by EP. On day 10, the colitis was evaluated histologically and by Western blot analysis. The colonic epithelial cell line MCE301 was exposed to HGF protein, and its proliferation and activated signaling pathway were analyzed. In vivo, the histological score improved and the number of Ki-67-positive epithelial cells increased in the HGF-treated mice compared with the controls. Western blot analysis showed enhanced expression of phospho-Akt in the HGF-treated mice compared with the controls. In vitro, HGF stimulated the proliferation of MCE301 cells. There was enhanced phospho-Akt expression for more than 48 h after HGF stimulation, although phospho-ERK1/2 was enhanced for only 10 min. LY-294002 or Akt small interfering RNA suppressed cell proliferation induced by HGF. Thus HGF induces the proliferation of colonic epithelial cells via the phosphatidylinositol 3-kinase/Akt signaling pathway. HGF gene therapy can attenuate acute colitis via epithelial cell proliferation through the PI3K/Akt pathway. These data suggested that HGF gene therapy by EP may be effective for the regeneration and repair of injured epithelial cells in inflammatory bowel disease.

HGF gene therapy attenuates renal allograft scarring by preventing the profibrotic inflammatory-induced mechanisms

Inflammatory processes and tissue scarring are characteristic features of chronic allograft nephropathy. Hepatocyte growth factor (HGF) has beneficial effects on renal fibrosis and it also ameliorates renal interstitial inflammation as it has been recently described. Contrarily to protein administration, intramuscular gene electrotransfer allows sustained release of HGF. So, here we hypothesized that gene therapy with human HGF would diminish the characteristic scarring of chronic allograft nephropathy either by antagonizing tissue fibrosis mechanisms or by reducing inflammation. Lewis rats transplanted with cold preserved Fischer kidneys received vehicle (NoHGF) or intramuscular plasmid DNA encoding HGF plus electroporation either before transplantation (IniHGF, early post-transplant cytoprotection of tubular cells) or 8/10 weeks after transplantation (DelHGF, delayed prevention of chronic mechanisms). Serum creatinine and proteinuria were measured every 4 weeks for 24 weeks. Grafts at 12 or 24 weeks were evaluated for glomerulosclerosis, fibrosis inflammatory cells and mediators, cell regeneration and tubulo-interstitial damage. Nontreated animals developed renal insufficiency, progressive proteinuria and fibrosis among other characteristic histological features of chronic allograft nephropathy. Treatment with human HGF, especially when delayed until the onset of fibrogenic mechanisms, reduced renal failure and mortality, diminished tubule-interstitial damage, induced cell regeneration, decreased inflammation, NF-kappaB activation, and profibrotic markers at 12 weeks and prevented late interstitial fibrosis and glomerulosclerosis. The effectiveness of HGF-gene therapy in the prevention of renal allograft scarring is related with the halt of profibrotic inflammatory-induced mechanisms.

Hepatocyte Growth Factor Attenuates Liver Fibrosis Induced by Bile Duct Ligation

Hepatic fibrosis is a common outcome of a variety of chronic liver diseases. Here we evaluated the therapeutic efficacy of hepatocyte growth factor (HGF) on liver fibrosis induced by bile duct ligation (BDL) and investigated potential mechanisms. Mice underwent BDL, followed by intravenous injections of naked HGF expression plasmid or control vector. HGF gene therapy markedly ameliorated hepatic fibrotic lesions, as demonstrated by reduced alpha-smooth muscle actin (alphaSMA) expression, attenuated deposition of type I and type III collagen, and normalized total hydroxyproline content. HGF also suppressed transforming growth factor-beta1 (TGF-beta1) expression. Interestingly, colocalization of alphaSMA and cytokeratin-19 in bile duct epithelium was observed, suggesting the possibility of biliary epithelial to myofibroblast transition after BDL. Cells that were still positive for cytokeratin-19 but actively producing type I collagen were found in the biliary epithelia and periductal region. Laminin staining revealed an impaired basement membrane of the bile duct epithelium in diseased liver. These lesions were largely prevented by HGF administration. In vitro, treatment of human biliary epithelial cells with TGF-beta1 induced alphaSMA and fibronectin expression and suppressed cytokeratin-19. HGF abolished the phenotypic conversion of biliary epithelial cells induced by TGF-beta1. These results suggest that HGF ameliorates hepatic biliary fibrosis in part by blocking bile duct epithelial to mesenchymal transition.

Combination gene therapy of HGF and truncated type II TGF-β receptor for rat liver cirrhosis after partial hepatectomy

In a cirrhotic liver, the regenerative ability and specific functions are impaired; a hepatic resection increases the possibility of postoperative liver failure. Hepatocyte growth factor (HGF) stimulates liver regeneration, accelerates restoration of hepatic function, and improves fibrosis. A truncated type II transforming growth factor-beta receptor (TbetaTR), which specifically inhibits TGF-beta signaling as a dominant-negative receptor, appears to prevent the progression of liver fibrosis. We demonstrated the therapeutic efficacy of adenovirus-mediated HGF and TbetaTR gene transduction after partial hepatectomy for liver cirrhosis. Rats were treated with dimethylnitrosamine for 3 weeks, and they all had severe cirrhosis. After partial hepatectomy (10%), we injected adenovirus expressing bacterial beta-galactosidase (AdLacZ), adenovirus expressing a truncated type II TGF-beta receptor (AdTbetaTR), adenovirus expressing hepatocyte growth factor (AdHGF), or AdTbetaTR + AdHGF into the portal vein, which was followed by an additional 2-week dimethylnitrosamine treatment. On histologic examination, fibrotic tissue had decreased in the livers of the AdTbetaTR + AdHGF-treated rats compared with rats that were treated by AdLacZ, AdTbetaTR alone, and AdHGF alone. Liver function, which included serum levels of alanine aminotransferase, improved significantly in AdTbetaTR + AdHGF-treated rats compared with all other groups. The number of hepatocytes that were positive for proliferating-cell nuclear antigen was greater (P < .05) in AdHGF alone and AdTbetaTR + AdHGF-treated rat livers than in AdLacZ- and AdTbetaTR-treated rats. All AdTbetaTR + AdHGF-treated rats survived >60 days, and AdTbetaTR + AdHGF treatment markedly improved the survival rate after a partial hepatectomy. Our results suggest that the combination of HGF and TbetaTR gene therapy may increase the possibility of hepatectomy in a cirrhotic liver by improving fibrosis, hepatic function, and hepatocyte regeneration.

Hepatocyte Growth Factor Gene Therapy Slows Down the Progression of Diabetic Nephropathy in db/db Mice

Background: Effect of hepatocyte growth factor (HGF) has scarcely been determined on diabetic nephropathy. Methods: Adenovirus encoding human HGF gene or LacZ gene (as the control) was injected into the hindlimb muscles of the C57BL/KsJ-db/db (db/db) mice at the age of 12 weeks, a model of genetic diabetes. Diabetic nephropathy was then evaluated at the age of 24 weeks. Results: The urine volume and albumin excretion progressively decreased in the control, whereas they remained unchanged in the HGF-treated group during the 12-week follow-up. The HGF gene therapy did not affect glucose metabolism. However, it resulted in a better renal function as evaluated by creatinine clearance (Ccr) than the control; Ccr was progressively worsened in controls (0.14 ± 0.02 liters/day) whereas unchanged in the HGF gene-treated group (0.38 ± 0.09 liters/day, p < 0.05). Kidneys of the HGF gene-treated mice showed glomeruli with greater area and cell population, smaller glomerular sclerotic index, and less fibrosis in both glomeruli and renal tubules, where apoptotic rate of glomerular endothelial cells and that of tubular epithelial cells were significantly decreased. TGF-β1 expression was significantly decreased in kidneys of the HGF gene-treated group. Finally, the HGF treatment significantly improved the long-term survival of db/db mice. Conclusions: The HGF gene delivery thus appeared to slow down the aggravation of diabetic nephropathy in db/db mice by attenuating progression from the hyperfiltration phase into the sclerotic phase through antiapoptotic and antifibrotic actions. The present findings suggest that the HGF gene delivery can be a novel therapeutic approach against diabetic nephropathy.