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Kisling A, Katwa LC. Pro-remodeling peptides modulate collagen α1(I) promoter activity in rat cardiac myofibroblasts. Biochem Biophys Res Commun 2019; 515:693-698. [PMID: 31186140 DOI: 10.1016/j.bbrc.2019.06.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 06/05/2019] [Indexed: 11/25/2022]
Abstract
Previous studies have extensively demonstrated the effect of endothelin-1 (ET-1), angiotensin II (Ang II), and TGF-β1 on the stimulation of collagen type I expression in cardiac myofibroblasts. However, the role of pro-remodeling peptides in the transcriptional regulation of the collagen promoter remains unclear. Thus, the purpose of this study was to investigate the net regulatory effects of pro-remodeling peptides on collagen type I promoter activity. Constructs of various lengths (300 bp, 1.1 kbp, 1.7 kbp, 2.3 kbp and 3.5 kbp) of the rat collagen α1(I) promoter were transfected into cardiac myofibroblasts in vitro and promoter activity was measured using chloramphenicol acetyl transferase (CAT) assays. Reduced promoter activity occurred across all treatments in myofibroblasts transfected with the 1.7 kbp construct. ET-1 was unable to increase promoter activity with constructs 300, 1.1, and 1.7 kbp, but induced promoter activity in cells with the 2.3 kbp construct. Additionally, while a combination of pro-remodeling peptides induced promoter activity across constructs, the resultant increase in the 2.3 and 3.5 kbp constructs were comparable to that observed from ET-1 treatment alone. Lastly, cells transfected with the entire promoter sequence had the lowest promoter activity. This data suggests that the collagen promoter is tightly regulated and that pro-remodeling factors produce an overall net effect on collagen expression, rather than additive.
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Affiliation(s)
- Andrew Kisling
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, 27834, USA
| | - Laxmansa C Katwa
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC, 27834, USA.
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Ye Z, Houssein HSH, Mahato RI. Bioconjugation of oligonucleotides for treating liver fibrosis. Oligonucleotides 2008; 17:349-404. [PMID: 18154454 DOI: 10.1089/oli.2007.0097] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Liver fibrosis results from chronic liver injury due to hepatitis B and C, excessive alcohol ingestion, and metal ion overload. Fibrosis culminates in cirrhosis and results in liver failure. Therefore, a potent antifibrotic therapy is urgently needed to reverse scarring and eliminate progression to cirrhosis. Although activated hepatic stellate cells (HSCs) remain the principle cell type responsible for liver fibrosis, perivascular fibroblasts of portal and central veins as well as periductular fibroblasts are other sources of fibrogenic cells. This review will critically discuss various treatment strategies for liver fibrosis, including prevention of liver injury, reduction of inflammation, inhibition of HSC activation, degradation of scar matrix, and inhibition of aberrant collagen synthesis. Oligonucleotides (ODNs) are short, single-stranded nucleic acids, which disrupt expression of target protein by binding to complementary mRNA or forming triplex with genomic DNA. Triplex forming oligonucleotides (TFOs) provide an attractive strategy for treating liver fibrosis. A series of TFOs have been developed for inhibiting the transcription of alpha1(I) collagen gene, which opens a new area for antifibrotic drugs. There will be in-depth discussion on the use of TFOs and how different bioconjugation strategies can be utilized for their site-specific delivery to HSCs or hepatocytes for enhanced antifibrotic activities. Various insights developed in individual strategy and the need for multipronged approaches will also be discussed.
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Affiliation(s)
- Zhaoyang Ye
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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Abstract
Despite tremendous progress in our understanding of fibrogenesis, injury stimuli process, inflammation, and hepatic stellate cell (HSC) activation, there is still no standard treatment for liver fibrosis. Delivery of small molecular weight drugs, proteins, and nucleic acids to specific liver cell types remains a challenge due to the overexpression of extracellular matrix (ECM) and consequent closure of sinusoidal gaps. In addition, activation of HSCs and subsequent release of inflammatory cytokines and infiltration of immune cells are other major obstacles to the treatment of liver fibrosis. To overcome these barriers, different therapeutic approaches are being investigated. Among them, the modulation of certain aberrant protein production is quite promising for treating liver fibrosis. In this review, we describe the mechanism of antisense, antigene, and RNA interference (RNAi) therapies and discuss how the backbone modification of oligonucleotides affects their in vivo stability, biodistribution, and bioactivity. Strategies for delivering these nucleic acids to specific cell types are discussed. This review critically addresses various insights developed with each individual strategy and for multipronged approaches, which will be helpful in achieving more effective outcomes.
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Affiliation(s)
- Kun Cheng
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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Abstract
We have previously demonstrated site-specific delivery of antiparallel phosphorothioate triplex forming oligonucleotide (TFO) specific to -165 to -141 promoter region of alpha1(I) collagen (abbreviated as APS165) to hepatic stellate cells (HSCs) of fibrotic rats after conjugation with mannose 6-phosphate-bovine serum albumin. However, we still need to determine whether there is correlation between transcription inhibition and triplex formation with genomic DNA. In this study, APS165 was modified with psoralen and the extent of triplex formation with alpha1(I) collagen DNA was determined in naked genomic DNA, isolated nuclei of HSC-T6 cells and whole cells by using a simple real-time PCR based method. In this method, a purification step was added to remove unbound APS165, which eliminated the possible artifacts during real-time PCR. Psoralen photoadduct formation was shown to be essential to retain triplex structure under denaturing conditions. On naked genomic DNA, 82.2% of DNA formed triplex and 36.7% of genomic DNA in isolated nuclei at 90 min contained triplex structure. As quantified by real-time PCR, 50% of genomic DNA in living cells at 12 h postincubation contained triplex structures. Furthermore, the triplex formation was dose-dependent with 26.5% and 50% of DNA having triplex structure at concentrations of 1 microM and 5 microM, respectively. Moreover, on a plasmid pCol-CAT220 containing rat alpha1(I) gene promoter (-225 to +113), 75.3% of triplex formation was observed, which was correlated with a 73.6% of transcription inhibition. These findings will further strengthen the therapeutic applications of APS165.
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Affiliation(s)
- Zhaoyang Ye
- Department of Pharmaceutical, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Ramareddy V. Guntaka
- Department of Molecular Sciences, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- * Corresponding authors Ram I. Mahato, Ph.D., 26 S Dunlap Street, Feurt 413, Memphis, TN 38163, USA, Tel: (901) 448-6929, Fax: (901) 448-6092, E-mail: , Http://cop.utmem.edu/rmahato. Ramareddy V. Guntaka, Ph. D., 101 Molecular Science Bldg., Memphis, TN 38163, USA, Tel: (901) 448-8230, Fax: (901) 448-8462, E-mail:
| | - Ram I. Mahato
- Department of Pharmaceutical, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- * Corresponding authors Ram I. Mahato, Ph.D., 26 S Dunlap Street, Feurt 413, Memphis, TN 38163, USA, Tel: (901) 448-6929, Fax: (901) 448-6092, E-mail: , Http://cop.utmem.edu/rmahato. Ramareddy V. Guntaka, Ph. D., 101 Molecular Science Bldg., Memphis, TN 38163, USA, Tel: (901) 448-8230, Fax: (901) 448-8462, E-mail:
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Mahato RI, Cheng K, Guntaka RV. Modulation of gene expression by antisense and antigene oligodeoxynucleotides and small interfering RNA. Expert Opin Drug Deliv 2006; 2:3-28. [PMID: 16296732 DOI: 10.1517/17425247.2.1.3] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Antisense oligodeoxynucleotides, triplex-forming oligodeoxynucleotides and double-stranded small interfering RNAs have great potential for the treatment of many severe and debilitating diseases. Concerted efforts from both industry and academia have made significant progress in turning these nucleic acid drugs into therapeutics, and there is already one FDA-approved antisense drug in the clinic. Despite the success of one product and several other ongoing clinical trials, challenges still exist in their stability, cellular uptake, disposition, site-specific delivery and therapeutic efficacy. The principles, strategies and delivery consideration of these nucleic acids are reviewed. Furthermore, the ways to overcome the biological barriers are also discussed so that therapeutic concentrations at their target sites can be maintained for a desired period.
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MESH Headings
- Animals
- DNA/chemistry
- DNA/genetics
- DNA/metabolism
- Drug Carriers
- Gene Expression Regulation
- Gene Silencing
- Gene Targeting/methods
- Genetic Therapy/methods
- Humans
- Nucleic Acid Conformation/drug effects
- Oligonucleotides, Antisense/chemistry
- Oligonucleotides, Antisense/genetics
- Oligonucleotides, Antisense/metabolism
- Oligonucleotides, Antisense/pharmacology
- Protein Biosynthesis/drug effects
- RNA Interference
- RNA Splicing/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Small Interfering/chemistry
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- Transcription, Genetic/drug effects
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Affiliation(s)
- Ram I Mahato
- University of Tennessee Health Science Center, Department of Pharmaceutical Sciences, 26 South Dunlap Street, Feurt Bldg RM 406, Memphis, TN 38163, USA.
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Sun W, Hou F, Panchenko MP, Smith BD. A member of the Y-box protein family interacts with an upstream element in the alpha1(I) collagen gene. Matrix Biol 2001; 20:527-41. [PMID: 11731270 DOI: 10.1016/s0945-053x(01)00163-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Transforming growth factor beta (TGF-beta) stimulates protein complex formation on a TGF-beta response element (TAE) found in the distal portion (-1624) of the collagen alpha 1(I) promoter. To identify the fibroblast proteins in this complex, an expression library constructed from human embryonic lung fibroblasts mRNA was screened using a tetramer of TAE. Y-box binding protein (YB-1), was identified as a protein in the TAE-protein complex. The protein expressed by phage clones formed a specific complex with labeled TAE but not mutated TAE (mTAE) similar to the complex formed with nuclear protein. Nuclear protein-TAE complexes isolated from native gels contained YB-1 by Western analysis. TGF-beta treatment increased the amount of YB-1 protein in nuclear extracts, decreased its amount in cytoplasm, but did not alter the steady state levels of YB-1 mRNA. A full-length YB-1 protein expressed in human lung fibroblasts was primarily located in the nucleus with punctate staining in cytoplasmic regions. The expression of YB-1 decreased in the cytoplasm after 2 h of TGF-beta treatment. Therefore, the increased binding activity seen in TGF-beta-stimulated nuclear extracts was due primarily to relocalization of YB-1 from the cytoplasm to the nuclear compartment. Co-transfection of YB-1 cDNA with a collagen promoter-reporter construct caused a dose-dependent activation of collagen promoter activity in rat fibroblasts whereas the promoter with a mutation in the TAE element was not sensitive to YB-1 co-expression. In conclusion, we have identified YB-1 as a protein that interacts with a TGF-beta response element in the distal region of the collagen alpha 1(I) gene. YB-1 protein activates the collagen promoter and translocates into the nucleus during TGF-beta addition to fibroblasts, suggesting a role for this protein in TGF-beta signaling.
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Affiliation(s)
- W Sun
- Department of Biochemistry, Boston University School of Medicine, 715 Albany St., Boston, MA 02118, USA
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Peterkofsky B, Gosiewska A, Singh K, Pearlman S, Mahmoodian F. Species differences in cis-elements of the Pro?1(I) procollagen promoter and their binding proteins. J Cell Biochem 1999. [DOI: 10.1002/(sici)1097-4644(19990601)73:3<408::aid-jcb12>3.0.co;2-d] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Dhalla AK, Ririe SS, Swamynathan SK, Weber KT, Guntaka RV. chk-YB-1b, a Y-box binding protein activates transcription from rat alpha1(I) procollagen gene promoter. Biochem J 1998; 336 ( Pt 2):373-9. [PMID: 9820814 PMCID: PMC1219881 DOI: 10.1042/bj3360373] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Type-I collagen, the predominant component of extracellular matrix, is a triple-helical protein consisting of two alpha1 polypeptides and one alpha2 polypeptide. Expression of alpha1 and alpha2 procollagen genes is co-ordinately regulated under both normal and various pathological conditions. However, the basis of this co-ordinate regulation is not well known. YB-1b, a Y-box protein, has been shown to bind to the polypyrimidine tract present in the alpha2 procollagen gene. Here, we show that chk-YB-1b, a YB-1 homologue, binds in a single-strand-sequence-specific manner to the highly conserved pyrimidine-rich sequences in both alpha1(I) and alpha2(I) procollagen promoters from different species, as demonstrated by electrophoretic-mobility-shift assays and by DNaseI footprinting experiments. Transiently transfected and retrovirally expressed antisense oligonucleotides directed against chk-YB-1b specifically inhibited the alpha1(I) procollagen promoter-driven transcription in cultured fibroblasts. Considering these data and the fact that the chk-YB-1b binding site is one of the few sites between alpha1(I) and alpha2(I) procollagen promoters that is conserved from chicken to human, it is proposed that chk-YB-1b may be involved in co-ordinate expression of these two collagen genes.
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Affiliation(s)
- A K Dhalla
- Division of Cardiology, Department of Internal Medicine, School of Medicine, University of Missouri-Columbia, Columbia, MO 65212, USA
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