Anti-fibrogenic analysis of HGF in intractable organ failures: Clinical potential of HGF as regenerative therapy

(1)使用HGF基因治疗改善肝硬化的策略在日本，现在至少有200万人患有难治性肝病，特别是，由于终末期肝硬化，每年有2万患者死亡。因此，重要的是建立一种新的治疗方法来克服这种疾病。使用动物模型，我们证明了HGF cDNA转染对于抑制肝硬化相关的病理条件是有用的。在接受DMN（一种肝毒性药物）慢性治疗的大鼠中，肝硬化进展，伴随着肝胶原蛋白和TGF-β 1水平的增加，导致DMN治疗开始后6周内死亡。另一方面，在转染人HQF cDNA后，甚至直到注射DMN 6周，所有的阿尔茨海默病大鼠仍然“活着”。未进行HGF基因治疗的大鼠表现出严重的肝功能衰竭，伴有TGF-β 1和胶原蛋白的增加。 ...更多信息 n级。相比之下，在HGF cDNA转染的DMN大鼠中几乎没有纤维化病变（包括基质过度积聚、肌成纤维细胞增生和TGF-β 1水平升高）。这些发现清楚地证明了HGF基因补充剂在最大限度地减少人类肝硬化方面的治疗潜力。(2)肝细胞生长因子对慢性肾功能衰竭进展的抑制作用慢性肾功能衰竭（CRF）的特征是实质肾单位的进行性丢失，代表肾纤维化，特别是在终末期。使用ICGN小鼠作为自发发生的CRF模型，我们发现内源性HGF对于抑制CRF的发作和进展至关重要：ICGN小鼠表现出肾功能不全，伴随着肾脏HGF水平的降低，与肾炎肾脏中TGF-β 1和胶原蛋白水平的增加相反。为了描述内源性HGF水平的损失，我们向肾病ICGN小鼠注射抗HGF IgG。值得注意的是，HGF中和处理导致TGF-β 1水平的过度表达以及内源性HGF表达的下调。此外，HGF-中和不仅抑制肾小管再生，而且还导致肾小管上皮细胞凋亡。因此，在HGF中和的ICGN小鼠中，肾纤维化和功能障碍快速进展。这些研究结果表明：1）内源性HGF对于减轻CRF相关的病理状态起关键作用;和2）HGF产生的损失与TGF-β 1水平的增加相互作用，是导致CRF的原因。因此，外源性肝细胞生长因子的补充可作为慢性肾功能衰竭治疗的新选择。(3)在扩张型心肌病仓鼠模型中，在出生后26 - 32周之间出现明显的心脏纤维化和肥大，同时心脏TGF-β 1和ANP水平升高，导致死亡。当用重组HGF治疗仓鼠时，心脏TGF-β 1和ANP水平显著抑制，导致心脏功能障碍和纤维化的改善。虽然目前还没有有效的治疗方法来改善终末期心肌病，但这是第一项证明终末期心肌病可逆性的研究。两者合计，显示HGF可用于改善心肌病中的病理状态。少

(1) Strategies for ameliorating liver cirrhosis using an HGF gene therapyIn Japan, at least two millions of people are now suffering from intractable liver diseases, and especially, twenty thousands patients become lethal a year, because of an end-stage liver cirrhosis. It is therefore important to establish a new therapy for overcoming this disorder. Using an animal model, we demonstrate that HGF cDNA transfection is useful for suppressing liver cirrhosis-related pathological conditions. In rats undergone chronic treatments with DMN (a hepatotoxic drug), liver cirrhosis progresses, accompanied with increases in hepatic collagen and TGF-beta1 levels, leading to be lethal within 6 weeks after onset of the DMN treatments. On the other hand, all of the cirrhotic rats remained "alive" after transfection of human HQF cDNA, even till 6 weeks of the DMN injections. The cirrhotic rats without the HGF gene treatment manifest severe liver failure, accompanied with increased TGF-beta1 and collage … More n levels. In contrast, there were few fibrotic lesions (including matrix over-accumulation, myofibroblast hyperplasia and elevated TGF-beta1 levels) in the HGF cDNA-transfected DMN rats. These findings clearly demonstrate a therapeutic potential of the HGF gene supplement for minimizing liver cirrhosis in humans.(2) Repressive effect of HGF on progression of chronic renal failureChronic renal failure (CRF) is characterized by a progressive loss in parenchymal nephrons and represents renal fibrosis, especially in an end-stage. Using ICGN mice as a spontaneously occurring CRF model, we found that endogenous HGF is critical for suppressing onset and progression of CRF: The ICGN mice manifest renal dysfunction, accompanied with a decrease in renal HGF level, in reciprocal to increases, in TGF-beta1 and collagen levels in the nephritic kidneys. In order to delineate the loss in endogenous HGF levels, we injected an anti-HGF IgG to the nephrotic ICGN mice. Of note, the HGF-neutralizing treatment led to over-expression of TGF-beta1 levels as well as to down-regulation of endogenous HGF expression. Furthermore, HGF-neutralization caused not only suppressed tubular regeneration but also tubular epithelial apoptosis. Consequently, there: was a rapid progression of renal fibrosis and dysfunction in the HGF-neutralized ICGN mice. These findings show that: 1) Endogenous HGF play a key role for lessening CRF-related pathological states; and 2) The loss of HGF production, in reciprocal to increased TGF-beta1 levels, is responsible for manifesting CRF. If so, exogenous HGF supplement should be considered as a new option for cure-oriented therapy of CRF.(3) HGF ameliorated heart fibrosis and dysfunction in a .model of dilative cardiomyopathyIn the hamster model of dilative cardiomyopathy, there was evident cardiac fibrosis and hypertrophy at ages between 26 and 32 weeks after birth, coinciding with increases in heart TGF-beta1 and ANP levels, leading to be lethal When the hamsters were treated with recombinant HGF, cardiac TGF-beta1 and ANP levels were significantly repressed, resulting in improvements in heart dysfunction: and fibrosis. Although there has been no treatment useful for improving end-stage cardiomyopathy, this is the first research demonstrating reversibility of end-stag-related cardiomyopathy. Taken together, HGF was shown to be available for ameliorating pathological states in the cardiomyopathy. Less