New and potential strategies for the treatment of PMM2-CDG.

BACKGROUND: Mutations in the PMM2 gene cause phosphomannomutase 2 deficiency (PMM2; MIM# 212065), which manifests as a congenital disorder of glycosylation (PMM2-CDG). Mutant PMM2 leads to the reduced conversion of Man-6-P to Man-1-P, which results in low concentrations of guanosine 5'-diphospho-D-mannose, a nucleotide-activated sugar essential for the construction of protein oligosaccharide chains. To date the only therapeutic options are preventive and symptomatic. SCOPE OF REVIEW: This review covers the latest advances in the search for a treatment for PMM2-CDG. MAJOR CONCLUSIONS: Treatments based on increasing Man-1-P levels have been proposed, along with the administration of different mannose derivates, employing enzyme inhibitors or repurposed drugs to increase the synthesis of GDP-Man. A single repurposed drug that might alleviate a severe neurological symptom associated with the disorder is now in clinical use. Proof of concept also exists regarding the use of pharmacological chaperones and/or proteostatic regulators to increase the concentration of hypomorphic PMM2 mutant proteins. GENERAL SIGNIFICANCE: The ongoing challenges facing the discovery of drugs to treat this orphan disease are discussed.

Apoprotein C-III: A review of its clinical implications.

Apoprotein C-III (apoC-III), originating from the apoA-I/C-III/A-IV gene cluster affected by multiple regulating factors, has been demonstrated to have a validated link with hypertriglyceridemia in humans. Following genome studies establishing the impact of apoC-III on both plasma triglyceride (TG) level and cardiovascular disease (CVD), apoC-III offers us a novel explanation attempting to resolve the long-existing confusion with regard to the atherogenic effect of TG. Notably, apoC-III exerts its atherogenic effect by means of not only intervening in the function and metabolism of various lipid molecules, but also accelerating pro-inflammatory effects between monocytes and endothelial cells. Data have suggested that diabetes, a common endocrine disease, also correlates closely with apoC-III in its apoptosis process of islet ßcells. In fact, apoC-III genes, with various mutations among individuals, are also found to have relevance to other diseases, including fatty liver disease. Fortunately, besides present day therapeutic strategies, such as lifestyle changes and lipid-lowering drug treatments, a promising new antisense drug specifically targeting on apoC-III gene expression opens up new avenues. This article mainly summarizes the clinical implication of apoC-III and its future directions of treatment.

Antisense MicroRNA Therapeutics in Cardiovascular Disease: Quo Vadis?

Heart failure (HF) is the end result of a diverse set of causes such as genetic cardiomyopathies, coronary artery disease, and hypertension and represents the primary cause of hospitalization in Europe. This serious clinical disorder is mostly associated with pathological remodeling of the myocardium, pump failure, and sudden death. While the survival of HF patients can be prolonged with conventional pharmacological therapies, the prognosis remains poor. New therapeutic modalities are thus needed that will target the underlying causes and not only the symptoms of the disease. Under chronic cardiac stress, small noncoding RNAs, in particular microRNAs, act as critical regulators of cardiac tissue remodeling and represent a new class of therapeutic targets in patients suffering from HF. Here, we focus on the potential use of microRNA inhibitors as a new treatment paradigm for HF.

Canonical and non-canonical barriers facing antimiR cancer therapeutics.

Once considered genetic "oddities", microRNAs (miRNAs) are now recognized as key epigenetic regulators of numerous biological processes, including some with a causal link to the pathogenesis, maintenance, and treatment of cancer. The crux of small RNA-based therapeutics lies in the antagonism of potent cellular targets; the main shortcoming of the field in general, lies in ineffective delivery. Inhibition of oncogenic miRNAs is a relatively nascent therapeutic concept, but as with predecessor RNA-based therapies, success hinges on delivery efficacy. This review will describes the canonical (e.g. pharmacokinetics and clearance, cellular uptake, endosome escape, etc.) and non-canonical (e.g. spatial localization and accessibility of miRNA, technical limitations of miRNA inhibition, off-target impacts, etc.) challenges to the delivery of antisense-based anti-miRNA therapeutics (i.e. antimiRs) for the treatment of cancer. Emphasis will be placed on how the current leading antimiR platforms-ranging from naked chemically modified oligonucleotides to nanoscale delivery vehicles-are affected by and overcome these barriers. The perplexity of antimiR delivery presents both engineering and biological hurdles that must be overcome in order to capitalize on the extensive pharmacological benefits of antagonizing tumor-associated miRNAs.

Silencing human genetic diseases with oligonucleotide-based therapies.

RNA interference is an endogenous mechanism present in most eukaryotic cells that enables degradation of specific mRNAs. Pharmacological exploitation of this mechanism for therapeutic purposes attracted a whole amount of attention in its initial years, but was later hampered due to difficulties in delivery of the pharmacological agents to the appropriate organ or tissue. Advances in recent years have to a certain level started to address this specific issue. Genetic diseases are caused by aberrations in gene sequences or structure; these particular abnormalities are in theory easily addressable by RNAi therapeutics. Sequencing of the human genome has largely contributed to the identification of alterations responsible for genetic conditions, thus facilitating the design of compounds that can address these diseases. This review addresses the currently on-going programs with the aim of developing RNAi and other antisense compounds for the treatment of genetic conditions and the pros and cons that these products may encounter along the way. The authors have focused on those programs that have reached clinical trials or are very close to do so.

Antisense technologies targeting fatty acid synthetic enzymes.

Fatty acid synthesis is a coordinated process involving multiple enzymes. Overexpression of some of these enzymes plays important roles in tumor growth and development. Therefore, these enzymes are attractive targets for cancer therapies. Antisense agents provide highly specific inhibition of the expression of target genes and thus have served as powerful tools for gene functional studies and potential therapeutic agents for cancers. This article reviews different types of antisense agents and their applications in the modulation of fatty acid synthesis. Patents of antisense agents targeting fatty acid synthetic enzymes are introduced. In addition, miR-122 has been shown to regulate the expression of fatty acid synthetic enzymes, and thus antisense agent patents that inhibit miR-122 expression are also discussed.

RLIP76, a glutathione-conjugate transporter, plays a major role in the pathogenesis of metabolic syndrome.

PURPOSE: Characteristic hypoglycemia, hypotriglyceridemia, hypocholesterolemia, lower body mass, and fat as well as pronounced insulin-sensitivity of RLIP76⁻/⁻ mice suggested to us the possibility that elevation of RLIP76 in response to stress could itself elicit metabolic syndrome (MSy). Indeed, if it were required for MSy, drugs used to treat MSy should have no effect on RLIP76⁻/⁻ mice. RESEARCH DESIGN AND METHODS: Blood glucose (BG) and lipid measurements were performed in RLIP76⁺/⁺ and RLIP76⁻/⁻ mice, using Ascensia Elite Glucometer® for glucose and ID Labs kits for cholesterol and triglycerides assays. The ultimate effectors of gluconeogenesis are the three enzymes: PEPCK, F-1,6-BPase, and G6Pase, and their expression is regulated by PPARγ and AMPK. The activity of these enzymes was tested by protocols standardized by us. Expressions of RLIP76, PPARα, PPARγ, HMGCR, pJNK, pAkt, and AMPK were performed by Western-blot and tissue staining. RESULTS: The concomitant activation of AMPK and PPARγ by inhibiting transport activity of RLIP76, despite inhibited activity of key glucocorticoid-regulated hepatic gluconeogenic enzymes like PEPCK, G6Pase and F-1,6-BP in RLIP76⁻/⁻ mice, is a salient finding of our studies. The decrease in RLIP76 protein expression by rosiglitazone and metformin is associated with an up-regulation of PPARγ and AMPK. CONCLUSIONS/SIGNIFICANCE: All four drugs, rosiglitazone, metformin, gemfibrozil and atorvastatin failed to affect glucose and lipid metabolism in RLIP76⁻/⁻ mice. Studies confirmed a model in which RLIP76 plays a central role in the pathogenesis of MSy and RLIP76 loss causes profound and global alterations of MSy signaling functions. RLIP76 is a novel target for single-molecule therapeutics for metabolic syndrome.

miR-21 mediates fibrogenic activation of pulmonary fibroblasts and lung fibrosis.

Uncontrolled extracellular matrix production by fibroblasts in response to tissue injury contributes to fibrotic diseases, such as idiopathic pulmonary fibrosis (IPF), a progressive and ultimately fatal process that currently has no cure. Although dysregulation of miRNAs is known to be involved in a variety of pathophysiologic processes, the role of miRNAs in fibrotic lung diseases is unclear. In this study, we found up-regulation of miR-21 in the lungs of mice with bleomycin-induced fibrosis and also in the lungs of patients with IPF. Increased miR-21 expression was primarily localized to myofibroblasts. Administration of miR-21 antisense probes diminished the severity of experimental lung fibrosis in mice, even when treatment was started 5-7 d after initiation of pulmonary injury. TGF-beta1, a central pathological mediator of fibrotic diseases, enhanced miR-21 expression in primary pulmonary fibroblasts. Increasing miR-21 levels promoted, whereas knocking down miR-21 attenuated, the pro-fibrogenic activity of TGF-beta1 in fibroblasts. A potential mechanism for the role of miR-21 in fibrosis is through regulating the expression of an inhibitory Smad, Smad7. These experiments demonstrate an important role for miR-21 in fibrotic lung diseases and also suggest a novel approach using miRNA therapeutics in treating clinically refractory fibrotic diseases, such as IPF.

Targeting the transforming growth factor-beta signalling pathway in metastatic cancer.

Transforming growth factor (TGF)-beta signalling plays a dichotomous role in tumour progression, acting as a tumour suppressor early and as a pro-metastatic pathway in late-stages. There is accumulating evidence that advanced-stage tumours produce excessive levels of TGF-beta, which acts to promote tumour growth, invasion and colonisation of secondary organs. In light of the pro-metastasis function, many strategies are currently being explored to antagonise the TGF-beta pathway as a treatment for metastatic cancers. Strategies such as using large molecule ligand traps, reducing the translational efficiency of TGF-beta ligands using antisense technology, and antagonising TGF-beta receptor I/II kinase function using small molecule inhibitors are the most prominent methods being explored today. Administration of anti-TGF-beta therapies alone, or in combination with immunosuppressive or cytotoxic therapies, has yielded promising results in the preclinical and clinical settings. Despite these successes, the temporal- and context-dependent roles of TGF-beta signalling in cancer has made it challenging to define patient subgroups that are most likely to respond, and the therapeutic regimens that will be most effective in the clinic. Novel mouse models and diagnostic tools are being developed today to circumvent these issues, which may potentially expedite anti-TGF-beta drug development and clinical application.

Chemically modified cell-penetrating peptides for the delivery of nucleic acids.

Short nucleic acids targeting biologically important RNAs and plasmids have been shown to be promising future therapeutics; however, their hydrophilic nature greatly limits their utility in clinics and therefore efficient delivery vectors are greatly needed. Cell-penetrating peptides (CPPs) are relatively short amphipathic and/or cationic peptides that are able to transport various biologically active molecules inside mammalian cells, both in vitro and in vivo, in a seemingly non-toxic fashion. Although CPPs have proved to be appealing drug delivery vehicles, their major limitation in nucleic acid delivery is that most of the internalized peptide-cargo is entrapped in endosomal compartments following endocytosis and the bioavailability is therefore severely reduced. Several groups are working towards overcoming this obstacle and this review highlights the evidence that by introducing chemical modification in CPPs, the bioavailability of delivered nucleic acids increases significantly.

Nitric oxide activity and isoenzyme expression in the senescence-accelerated mouse p8 model of Alzheimer's disease: effects of anti-amyloid antibody and antisense treatments.

Amyloid beta protein (Abeta) in Alzheimer's disease induces oxidative stress through several mechanisms, including stimulation of nitric oxide synthase (NOS) activity. We examined NOS activity and expression in the senescence-accelerated mouse P8 (SAMP8) line. The SAMP8 strain develops with aging cognitive impairments, increases in Abeta, and oxidative stress, all reversed by amyloid precursor protein antisense or Abeta antibody treatment. We found here that hippocampal NOS activity in 12-month-old SAMP8 mice was nearly double that of 2-month-old SAMP8 or CD-1 mice, but with no change in NOS isoenzyme mRNA and protein levels. Antisense or antibody treatment further increased NOS activity in aged SAMP8 mice. Antisense treatment increased inducible NOS (iNOS) mRNA levels, decreased neuronal NOS mRNA and protein levels, but did not affect endothelial NOS (eNOS) or iNOS protein or eNOS mRNA levels. These results suggest a complex relation between Abeta and NOS in the SAMP8 that is largely mediated through posttranslational mechanisms.

Novel therapeutic modalities to address nondrugable protein interaction targets.

Small molecule drugs are relatively effective in working on 'drugable' targets such as GPCRs, ion channels, kinases, proteases, etc but ineffective at blocking protein-protein interactions that represent an emerging class of 'nondrugable' central nervous system (CNS) targets. This article provides an overview of novel therapeutic modalities such as biologics (in particular antibodies) and emerging oligonucleotide therapeutics such as antisense, small-interfering RNA, and aptamers. Their key properties, overall strengths and limitations, and their utility as tools for target validation are presented. In addition, issues with regard to CNS targets as it relates to the blood-brain barrier penetration are discussed. Finally, examples of their application as therapeutics for the treatment of pain and some neurological disorders such as Alzheimer's disease, multiple sclerosis, Huntington's disease, and Parkinson's disease are provided.

Hepatocellular carcinoma-related gene targeting using the large circular antisense library.

The large circular (LC)-antisense library to the 221 unigene clone was constructed and utilized in the identification of genes functionally involved in the growth of hepatocellular carcinoma cells. We identified that 37 out of the 221 members of the antisense library exerted a marked inhibitory effect on the growth of Huh-7. The putative functional categorization of each gene was then conducted on the basis of the sequence information. The relative expression levels of target genes were measured and treated with two LC-antisense molecules by real-time PCR. LC-antisense to EIF3EIP and AFP abolished the expression of EIF3EIP and AFP to the level of approximately 7 and 39% compared to the control treatment in Huh-7 cells, respectively. LC-antisense molecules to EIF3EIP and AFP were simultaneously treated with 5-FU to Huh-7 cells. Two LC-antisense molecules showed additive effects with 5-FU compared with 5-FU alone, respectively. The combination of LC-antisense molecules and 5-FU showed a dramatic increase of sub-G1 apoptotic cell death fraction in cell cycle analysis, respectively. Therefore, these candidates may be used as target genes for drug development or adjuvant of conventional chemotherapeutic drugs.

rAAV-asPLB transfer attenuates abnormal sarcoplasmic reticulum Ca2+ -ATPase activity and cardiac dysfunction in rats with myocardial infarction.

BACKGROUND: Diminished myocardial sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) activity and upregulated phospholamban (PLB) level during cardiac dysfunction, had been reported in many studies. AIMS: The current study was designed to examine the effects of rAAV-antisense phospholamban (asPLB) gene transfer on cardiac function, SERCA expression and activity, as well as PLB expression and phosphorylation (Pser16-PLB), in a rat myocardial infarction (MI) model. METHODS AND RESULTS: Rat MI model was generated by ligating the left anterior descending coronary artery. Four weeks later, left ventricular ejection fraction (LVEF), left ventricular systolic pressure (LVSP), the maximal rates of increase and decrease in intraventricular pressure (+/-dp/dt(max)) were significantly depressed, and left ventricular end diastolic pressure (LVEDP) was increased. Myocardial PLB was markedly increased while both SERCA activity and Pser16-PLB level were decreased. In rAAV-asPLB transfected rats, rAAV-asPLB, which was injected into the myocardium around the infarction area immediately after the coronary artery ligation, effectively attenuated the depression of cardiac function, significantly inhibited the expression of PLB, restored Pser16-PLB level and enhanced myocardium SERCA activity. CONCLUSION: rAAV-asPLB transfer in rats with MI effectively prevented the progression of heart failure.

Antisense therapeutics for tumor treatment: the TGF-beta2 inhibitor AP 12009 in clinical development against malignant tumors.

Overexpression of the cytokine transforming growth factor-beta 2 (TGF-beta2) is a hallmark of various malignant tumors including pancreatic carcinoma, malignant glioma, metastasizing melanoma, and metastatic colorectal carcinoma. This is due to the pivotal role of TGF-beta2 as it regulates key mechanisms of tumor development, namely immunosuppression, metastasis, angiogenesis, and proliferation. The antisense technology is an innovative technique offering a targeted approach for the treatment of different highly aggressive tumors and other diseases. Antisense oligonucleotides are being developed to inhibit the production of disease-causing proteins at the molecular level. The immunotherapeutic approach with the phosphorothioate oligodeoxynucleotide AP 12009 for the treatment of malignant tumors is based on the specific inhibition of TGF-beta2. After providing preclinical proof of concept, the safety and efficacy of AP 12009 were assessed in clinical phase I/II open-label dose-escalation studies in recurrent or refractory high-grade glioma patients. Median survival time after recurrence exceeded the current literature data for chemotherapy. Currently, phase I/II study in advanced pancreatic carcinoma, metastatic melanoma, and metastatic colorectal carcinoma and a phase IIb study in recurrent or refractory high-grade glioma are ongoing. The preclinical as well as the clinical results implicate targeted TGF-beta2 suppression as a promising therapeutic approach for malignant tumor therapy.

Targeting urokinase-type plasminogen activator and its receptor for cancer therapy.

Cancer invasion and metastasis are highly complex processes and a serine protease urokinase-type plasminogen activator/urokinase-type plasminogen activator receptor system has been postulated to play a central role in the mediation of cancer progression. Of note, malignant tumor urokinase-type plasminogen activator and urokinase-type plasminogen activator receptor levels have been found to vary considerably, and to be related to patient prognosis. In mouse models, the urokinase-type plasminogen activator/urokinase-type plasminogen activator receptor system has been studied extensively as a target for anticancer therapy using a variety of approaches. In this review, we discuss the advances in the various modalities that have been used to target the urokinase-type plasminogen activator/urokinase-type plasminogen activator receptor system, including protein-based and peptide-based drugs, antisense therapy, and RNA interference technology. In particular, preclinical mouse model studies that used human tumor xenografts are reviewed.

Molecular therapies for malignant glioma.

Due to the dismal prognosis of malignant glioma with currently available therapies there is an urgent need for new treatments based on a better molecular understanding of gliomagenesis. Several concepts of molecular therapies for malignant glioma are currently being studied in preclinical and clinical settings, including small molecules targeting specific receptor-mediated signaling pathways and gene therapy. Many growth factors, growth factor receptors--usually receptor tyrosine kinases--and receptor-associated signaling pathways are critically involved in gliomagenesis. Numerous selective inhibitors, which specifically block such molecules, are currently evaluated for clinical applicability. Several gene therapy approaches have shown antitumor efficacy in experimental studies, and the first clinical trials for the treatment of malignant glioma were conducted in the 1990s. In clinical trials, retroviral herpes-simplex-thymidinkinase- (HSV-Tk-) gene therapy has been the pioneering and most commonly used approach. However, efficient gene delivery into the tumor cells still remains the crucial obstacle for successful clinical gene therapy. During the past few years a number of new gene transfer vectors based on adeno-, adeno-associated-, herpes- and lentiviruses as well as new carrier cell systems, including neural and endothelial progenitor cells, have been developed. In addition, antisense technologies have advanced in recent years and entered clinical testing utilizing intratumoral administration by convection-enhanced delivery, exemplified by ongoing clinical trials of intratumoral administration of antisense TGF-beta. This paper summarizes some of these recent developments in molecular therapies for malignant glioma, focusing on targeted therapies using selective small molecules and gene therapy concepts.

DNA-based therapeutics and DNA delivery systems: a comprehensive review.

The past several years have witnessed the evolution of gene medicine from an experimental technology into a viable strategy for developing therapeutics for a wide range of human disorders. Numerous prototype DNA-based biopharmaceuticals can now control disease progression by induction and/or inhibition of genes. These potent therapeutics include plasmids containing transgenes, oligonucleotides, aptamers, ribozymes, DNAzymes, and small interfering RNAs. Although only 2 DNA-based pharmaceuticals (an antisense oligonucleotide formulation, Vitravene, (USA, 1998), and an adenoviral gene therapy treatment, Gendicine (China, 2003), have received approval from regulatory agencies; numerous candidates are in advanced stages of human clinical trials. Selection of drugs on the basis of DNA sequence and structure has a reduced potential for toxicity, should result in fewer side effects, and therefore should eventually yield safer drugs than those currently available. These predictions are based on the high selectivity and specificity of such molecules for recognition of their molecular targets. However, poor cellular uptake and rapid in vivo degradation of DNA-based therapeutics necessitate the use of delivery systems to facilitate cellular internalization and preserve their activity. This review discusses the basis of structural design, mode of action, and applications of DNA-based therapeutics. The mechanisms of cellular uptake and intracellular trafficking of DNA-based therapeutics are examined, and the constraints these transport processes impose on the choice of delivery systems are summarized. Finally, the development of some of the most promising currently available DNA delivery platforms is discussed, and the merits and drawbacks of each approach are evaluated.

Modulation of tamoxifen sensitivity by antisense Bcl-2 and trastuzumab in breast carcinoma cells.

BACKGROUND: Because the overexpression of HER-2 and Bcl-2 is associated with resistance to tamoxifen (TAM), the authors examined the effect of antisense (AS) Bcl-2 on sensitivity to TAM compared with the effect of trastuzumab on sensitivity to TAM in breast carcinoma cell lines. METHODS: Drug sensitivity was assessed in vitro using a [3-4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay with the breast carcinoma cell lines ZR-75-1, MDA-MB-453, and BT-474. AS Bcl-2 18-mer phosphorothioate oligonucleotide was applied. Apoptotic cell death was assessed with the terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick-end labeling method, and gene expression was evaluated with Western blot analysis. RESULTS: The expression of Bcl-2 was identified in ZR-75-1 and BT-474 cells and, to a lesser extent, in MDA-MB-453 cells. Overexpression of HER-2 was identified in BT-474 cells, and moderate expression was identified in MDA-MB-453 and ZR-75-1 cells. Combination treatment with trastuzumab or AS Bcl-2 enhanced TAM sensitivity in ZR-75-1 cells, which showed 50% inhibitory concentration (IC50) values of 0.9 microM (7.2-fold increase) and 0.5 microM (13.0-fold), respectively. Combination treatment with trastuzumab or AS Bcl-2 slightly enhanced TAM sensitivity of BT-474 cells, with IC50 values of 3.0 microM (1.3-fold) and 1.5 microM (2.6-fold), respectively. The sensitivity of MDA-MB-453 cells to TAM was not enhanced by combination with trastuzumab or AS Bcl-2. Modulation of TAM sensitivity by AS Bcl-2 was superior to modulation by trastuzumab in HER-2-expressing and Bcl-2-expressing breast carcinoma cells. Enhanced sensitivity in combination with AS Bcl-2 was associated with down-regulation of Bcl-2 and pAkt, which was correlated with the induction of Bax and caspase-3, leading to apoptosis. CONCLUSIONS: AS Bcl-2 appeared to be superior to trastuzumab with respect to regulating the signal-transduction pathways involved in breast carcinoma cells.

Effects of a plasmid expressing antisense tissue inhibitor of metalloproteinase-1 on liver fibrosis in rats.

BACKGROUND: No efficient therapy for liver fibrosis has been available. This study was aimed to provide evidence that the introduction of a plasmid expressing antisense tissue inhibitor of metalloproteinase-1 (TIMP-1) into a rat model of immunologically induced liver fibrosis can result in the increased activity of interstitial collagenase, thus enhancing the degradation of collagen. METHODS: Real-time nested polymerase chain reaction (RT-Nested-PCR) and gene recombination techniques were used to construct a rat antisense TIMP-1 recombinant plasmid that can be expressed in eukaryotic cells. Both the recombinant plasmid and an empty vector (pcDNA3) were encapsulated with glycosyl-poly-L-lysine and injected into rats suffering from pig serum-induced liver fibrosis. The expression of exogenous transfected plasmid was assessed by Northern blot, RT-PCR, and Western blot. Hepatic interstitial collagenase activity was detected using fluorescinisothiocyanate (FITC)-labeled type I collagen. In addition to hepatic hydroxyproline content, hepatic collagen types I and III were detected by immunohistochemical staining, and the stages of liver fibrosis by Van Gieson staining. RESULTS: Exogenous antisense TIMP-1 was successfully expressed in vivo and could block the gene and protein expression of TIMP-1. Active and latent hepatic interstitial collagenase activities were elevated (P < 0.01), hepatic hydroxyproline content and the accumulation of collagen types I and III were lowered, and liver fibrosis was alleviated in the antisense TIMP-1 group (P < 0.01) as compared with the model group. CONCLUSION: The results demonstrate that antisense TIMP-1 recombinant plasmids have some inhibitory effect on liver fibrosis.