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1.
Mol Ther Methods Clin Dev ; 22: 330-337, 2021 Sep 10.
Article in English | MEDLINE | ID: mdl-34514025

ABSTRACT

Hypophosphatasia (HPP) is an inherited skeletal disease characterized by defective bone and tooth mineralization due to a deficiency in tissue-nonspecific alkaline phosphatase (TNALP). Patients with the severe infantile form of HPP may appear normal at birth, but their prognosis is very poor. To develop a practical gene therapy for HPP, we endeavored to phenotypically correct TNALP knockout (Akp2 -/- ) mice through adeno-associated virus type 8 (AAV8) vector-mediated, muscle-directed, TNALP expression. Following treatment of neonatal Akp2 -/- mice with a single intramuscular injection of ARU-2801 (AAV8-TNALP-D10-vector) at 1.0 × 1012 vector genomes/body, high plasma ALP levels (19.38 ± 5.02 U/mL) were detected for up to 18 months, and computed tomography analysis showed mature bone mineralization. Histochemical staining for ALP activity in the knee joint revealed ALP activity on the surface of the endosteal bone of mice. Throughout their lives, the surviving treated Akp2 -/- mice exhibited normal physical activity and a healthy appearance, whereas untreated controls died within 3 weeks. No ectopic calcification or abnormal calcium metabolism was detected in the treated mice. These findings suggest that ARU-2801-mediated neonatal intramuscular gene therapy is both safe and effective, and that this strategy could be a practical option for treatment of the severe infantile form of HPP.

2.
J Nippon Med Sch ; 85(6): 322-329, 2018.
Article in English | MEDLINE | ID: mdl-30568058

ABSTRACT

BACKGROUND: Alcohol dehydrogenase 3 (ADH3) plays major roles not only in alcohol metabolism but also in nitric oxide metabolism as S-nitrosoglutathione reductase (GSNOR). ADH3/GSNOR regulates both adipogenesis and osteogenesis through the denitrosylation of peroxisome proliferator-activated receptor γ. The current study investigated the contribution of ADH3 to the development of alcoholic osteoporosis in chronic alcohol consumption (CAC). METHODS: Nine-week-old male mice of different ADH genotypes [wild-type (WT) and Adh3-/-] were administered a 10% ethanol solution for 12 months. The femurs were evaluated by histochemical staining and computed tomography-based bone densitometry. The mRNA levels of ADH3 were evaluated in the WT mice by reverse transcription-quantitative polymerase chain reaction. RESULTS: The Adh3-/- control mice exhibited increased activities of both osteoblasts and osteoclasts and lower bone masses than the WT control mice. CAC exhibited no remarkable change in osteoblastic and osteoclastic activities, but decreased bone masses were observed in WT mice despite an increase in the mRNA levels of ADH3. Conversely, bone masses in the Adh3-/- control mice were not reduced after CAC. CONCLUSIONS: The Adh3-/- control mice exhibited a high turnover of osteoporosis since osteoclastogenesis dominated osteoblastogenesis; however, bone resorption was not enhanced after CAC. In comparison, CAC lead to alcoholic osteoporosis in WT mice, accompanied by increased mRNA levels of ADH3. Hence, ADH3 can prevent osteoporosis development in normal ADH genotypes with no alcohol ingestion. However, ADH3 contributes to the development of alcoholic osteoporosis under CAC by participating in alcohol metabolism, increasing metabolic toxicity, and lowering GSNO reducing activity.


Subject(s)
Alcohol Dehydrogenase/genetics , Ethanol/toxicity , Femur/drug effects , Osteoporosis/genetics , Alcohol Dehydrogenase/metabolism , Animals , Central Nervous System Depressants/administration & dosage , Central Nervous System Depressants/metabolism , Central Nervous System Depressants/toxicity , Ethanol/administration & dosage , Ethanol/metabolism , Femur/diagnostic imaging , Femur/pathology , Gene Expression Regulation, Enzymologic/drug effects , Genotype , Male , Mice, Inbred C57BL , Mice, Knockout , Osteoblasts/metabolism , Osteoclasts/metabolism , Osteoporosis/chemically induced , Osteoporosis/enzymology , Tomography, X-Ray Computed
3.
Mol Ther ; 25(1): 296-302, 2017 01 04.
Article in English | MEDLINE | ID: mdl-28129123

ABSTRACT

The retina is an ideal target for gene therapy because of its easy accessibility and limited immunological response. We previously reported that intravitreally injected adeno-associated virus (AAV) vector transduced the inner retina with high efficiency in a rodent model. In large animals, however, the efficiency of retinal transduction was low, because the vitreous and internal limiting membrane (ILM) acted as barriers to transduction. To overcome these barriers in cynomolgus monkeys, we performed vitrectomy (VIT) and ILM peeling before AAV vector injection. Following intravitreal injection of 50 µL triple-mutated self-complementary AAV serotype 2 vector encoding EGFP, transduction efficiency was analyzed. Little expression of GFP was detected in the control and VIT groups, but in the VIT+ILM group, strong GFP expression was detected within the peeled ILM area. To detect potential adverse effects, we monitored the retinas using color fundus photography, optical coherence tomography, and electroretinography. No serious side effects associated with the pretreatment were observed. These results indicate that surgical ILM peeling before AAV vector administration would be safe and useful for efficient transduction of the nonhuman primate retina and provide therapeutic benefits for the treatment of retinal diseases.


Subject(s)
Dependovirus/genetics , Genetic Vectors/genetics , Retina/metabolism , Transduction, Genetic , Transgenes , Animals , Electroretinography , Ependymoglial Cells/metabolism , Ependymoglial Cells/pathology , Female , Fluorescein Angiography , Gene Expression , Gene Transfer Techniques , Genes, Reporter , Genetic Therapy , Genetic Vectors/administration & dosage , Inflammation/genetics , Inflammation/metabolism , Inflammation/pathology , Intravitreal Injections , Macaca fascicularis , Retina/pathology , Tomography, Optical Coherence
4.
Mol Vis ; 22: 816-26, 2016.
Article in English | MEDLINE | ID: mdl-27440998

ABSTRACT

PURPOSE: We examined the neuroprotective effects of exogenous brain-derived neurotrophic factor (BDNF), which provides protection to retinal ganglion cells (RGCs) in rodents, in a model of transient intraocular pressure (IOP) elevation using a mutant (triple Y-F) self-complementary adeno-associated virus type 2 vector encoding BDNF (tm-scAAV2-BDNF). METHODS: The tm-scAAV2-BDNF or control vector encoding green fluorescent protein (GFP; tm-scAAV2-GFP) was intravitreally administered to rats, which were then divided into four groups: control, ischemia/reperfusion (I/R) injury only, I/R injury with tm-scAAV2-GFP, and tm-scAAV2-BDNF. I/R injury was then induced by transiently increasing IOP, after which the rats were euthanized to measure the inner retinal thickness and cell counts in the RGC layer. RESULTS: Intravitreous injection of tm-scAAV2-BDNF resulted in high levels of BDNF expression in the neural retina. Histological analysis showed that the inner retinal thickness and cell numbers in the RGC layer were preserved after transient IOP elevation in eyes treated with tm-scAAV2-BDNF but not in the other I/R groups. Significantly reduced glial fibrillary acidic protein (GFAP) immunostaining after I/R injury in the rats that received tm-scAAV2-BDNF indicated reduced retinal stress, and electroretinogram (ERG) analysis confirmed preservation of retinal function in the tm-scAAV2-BDNF group. CONCLUSIONS: These results demonstrate the feasibility and effectiveness of neuroprotective gene therapy using tm-scAAV2-BDNF to protect the inner retina from transiently high intraocular pressure. An in vivo gene therapeutic approach to the clinical management of retinal diseases in conditions such as glaucoma, retinal artery occlusion, hypertensive retinopathy, and diabetic retinopathy thus appears feasible.


Subject(s)
Brain-Derived Neurotrophic Factor/genetics , Brain-Derived Neurotrophic Factor/therapeutic use , Dependovirus/metabolism , Intraocular Pressure , Mutation/genetics , Tyrosine/genetics , Animals , Cell Count , Disease Models, Animal , Electroretinography , Glial Fibrillary Acidic Protein/metabolism , Green Fluorescent Proteins/metabolism , Humans , Rats, Sprague-Dawley , Retina/injuries , Retina/pathology , Retinal Ganglion Cells/metabolism , Retinal Ganglion Cells/pathology , Transduction, Genetic
5.
Mol Ther Methods Clin Dev ; 3: 15059, 2016.
Article in English | MEDLINE | ID: mdl-26904710

ABSTRACT

Hypophosphatasia (HPP) is an inherited disease caused by genetic mutations in the gene encoding tissue-nonspecific alkaline phosphatase (TNALP). This results in defects in bone and tooth mineralization. We recently demonstrated that TNALP-deficient (Akp2 (-/-) ) mice, which mimic the phenotype of the severe infantile form of HPP, can be treated by intravenous injection of a recombinant adeno-associated virus (rAAV) expressing bone-targeted TNALP with deca-aspartates at the C-terminus (TNALP-D10) driven by the tissue-nonspecific CAG promoter. To develop a safer and more clinically applicable transduction strategy for HPP gene therapy, we constructed a self-complementary type 8 AAV (scAAV8) vector that expresses TNALP-D10 via the muscle creatine kinase (MCK) promoter (scAAV8-MCK-TNALP-D10) and examined the efficacy of muscle-directed gene therapy. When scAAV8-MCK-TNALP-D10 was injected into the bilateral quadriceps of neonatal Akp2 (-/-) mice, the treated mice grew well and survived for more than 3 months, with a healthy appearance and normal locomotion. Improved bone architecture, but limited elongation of the long bone, was demonstrated on X-ray images. Micro-CT analysis showed hypomineralization and abnormal architecture of the trabecular bone in the epiphysis. These results suggest that rAAV-mediated, muscle-specific expression of TNALP-D10 represents a safe and practical option to treat the severe infantile form of HPP.

6.
Hum Gene Ther ; 26(12): 801-12, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26467745

ABSTRACT

Hypophosphatasia (HPP) is an inherited skeletal and dental disease caused by loss-of-function mutations in the gene that encodes tissue-nonspecific alkaline phosphatase (TNALP). The major symptoms of severe forms of the disease are bone defects, respiratory insufficiency, and epileptic seizures. In 2015, enzyme replacement therapy (ERT) using recombinant bone-targeted TNALP with deca-aspartate (D10) motif was approved to treat pediatric HPP patients in Japan, Canada, and Europe. However, the ERT requires repeated subcutaneous administration of the enzyme because of the short half-life in serum. In the present study, we evaluated the feasibility of neonatal ex vivo gene therapy in TNALP knockout (Akp2(-/-)) HPP mice using lentivirally transduced bone marrow cells (BMC) expressing bone-targeted TNALP in which a D10 sequence was linked to the C-terminus of soluble TNALP (TNALP-D10). The Akp2(-/-) mice usually die within 20 days because of growth failure, epileptic seizures, and hypomineralization. However, an intravenous transplantation of BMC expressing TNALP-D10 (ALP-BMC) into neonatal Akp2(-/-) mice prolonged survival of the mice with improved bone mineralization compared with untransduced BMC-transplanted Akp2(-/-) mice. The treated Akp2(-/-) mice were normal in appearance and experienced no seizures during the experimental period. The lentivirally transduced BMC were efficiently engrafted in the recipient mice and supplied TNALP-D10 continuously at a therapeutic level for at least 3 months. Moreover, TNALP-D10 overexpression did not affect multilineage reconstitution in the recipient mice. The plasma ALP activity was sustained at high levels in the treated mice, and tissue ALP activity was selectively detected on bone surfaces, not in the kidneys or other organs. No ectopic calcification was observed in the ALP-BMC-treated mice. These results indicate that lentivirally transduced BMC can serve as a reservoir for stem cell-based ERT to rescue the Akp2(-/-) phenotype. Neonatal ex vivo gene therapy thus appears to be a possible treatment option for treating severe HPP.


Subject(s)
Alkaline Phosphatase/genetics , Bone Marrow Cells/enzymology , Genes, Lethal , Genetic Therapy/methods , Hypophosphatasia/therapy , Lentivirus/genetics , Alkaline Phosphatase/deficiency , Amino Acid Motifs , Animals , Animals, Newborn , Bone Marrow Cells/cytology , Bone Marrow Transplantation , Disease Models, Animal , Enzyme Replacement Therapy/methods , Female , Gene Expression , Genetic Vectors/chemistry , Genetic Vectors/metabolism , Humans , Hypophosphatasia/genetics , Hypophosphatasia/mortality , Hypophosphatasia/pathology , Lentivirus/metabolism , Mice , Mice, Knockout , Molecular Sequence Data , Phenotype , Primary Cell Culture , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Survival Analysis , Transduction, Genetic , Treatment Outcome
7.
Cornea ; 33(12): 1342-7, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25255138

ABSTRACT

PURPOSE: Although tear hyperosmolarity is assumed to play a major role in dry eye disease, correlation between the level of hyperosmolarity and inflammation remains unclear. The purpose of this study was to examine the effect of short-time hyperosmolarity exposure in the production of inflammatory cytokines in corneal epithelial cells in vitro. METHODS: Human corneal epithelial (HCE) cells were cultured under different osmotic conditions [310 (control), and 400-1000 mOsm]. Lactate dehydrogenase (LDH) release after short-term (10 minutes) or long-term (24 hours) hyperosmotic stress exposure was evaluated to determine HCE cell cytotoxicity. Production of inflammatory cytokines, including IL-6, IL-1ß, IL-8, IL-23, and TGF-ß1, due to hyperosmotic stress was also measured by enzyme-linked immunosorbent assay and semiquantitative real-time polymerase chain reaction. RESULTS: After a 24-hour culture, exposures above 700 mOsm caused all HCE cells to die, 500 and 600 mOsm damaged the cells, whereas 400 mOsm caused no morphological changes. However, there was a significant increase in the release of LDH after 24-hour cultures, even in 400 mOsm. In contrast, LDH examination showed that there was no cytotoxicity for the 10-minute exposures, even at above 800 mOsm. The significant increases in IL-6 production and mRNA expression at 700 mOsm during the short-time exposures were both dependent on the osmolarity. Other cytokines such as IL-1ß, IL-8, IL-23, and TGF-ß1 were not detected. CONCLUSIONS: Short-time hyperosmolarity exposure may activate IL-6 expression and production in HCE cells without cytotoxicity. These observations suggest that hyperosmolarity could cause inflammation on the ocular surface in dry eye disease.


Subject(s)
Epithelium, Corneal/drug effects , Interleukin-6/metabolism , Saline Solution, Hypertonic/toxicity , Cells, Cultured , Enzyme-Linked Immunosorbent Assay , Epithelium, Corneal/metabolism , Epithelium, Corneal/pathology , Humans , Interleukin-1beta/metabolism , Interleukins/metabolism , L-Lactate Dehydrogenase/metabolism , Osmolar Concentration , Osmotic Pressure/drug effects , Real-Time Polymerase Chain Reaction
8.
Mol Vis ; 20: 488-96, 2014.
Article in English | MEDLINE | ID: mdl-24744609

ABSTRACT

PURPOSE: To assess the feasibility of a gene therapeutic approach to treating choroidal neovascularization (CNV), we generated an adeno-associated virus type 8 vector (AAV2/8) encoding an siRNA targeting vascular endothelial growth factor (VEGF), and determined the AAV2/8 vector's ability to inhibit angiogenesis. METHODS: We initially transfected 3T3 cells expressing VEGF with the AAV2/8 plasmid vector psiRNA-VEGF using the H1 promoter and found that VEGF expression was significantly diminished in the transfectants. We next injected 1 µl (3 × 10(14) vg/ml) of AAV2/8 vector encoding siRNA targeting VEGF (AAV2/8/SmVEGF-2; n = 12) or control vector encoding green fluorescent protein (GFP) (AAV2/8/GFP; n = 14) into the subretinal space in C57BL/6 mice. One week later, CNV was induced by using a diode laser to make four separate choroidal burns around the optic nerve in each eye. After an additional 2 weeks, the eyes were removed for flat mount analysis of the CNV surface area. RESULTS: Subretinal delivery of AAV2/8/SmVEGF-2 significantly diminished CNV at the laser lesions, compared to AAV8/GFP (1597.3 ± 2077.2 versus 5039.5 ± 4055.9 µm(2); p<0.05). Using an enzyme-linked immunosorbent assay, we found that VEGF levels were reduced by approximately half in the AAV2/8/SmVEGF-2 treated eyes. CONCLUSIONS: These results suggest that siRNA-VEGF can be expressed across the retina and that long-term suppression of CNV is possible through the use of stable AAV2/8-mediated siRNA-VEGF expression. In vivo gene therapy may thus be a feasible approach to the clinical management of CNV in conditions such as age-related macular degeneration.


Subject(s)
Choroidal Neovascularization/therapy , Dependovirus/metabolism , Genetic Vectors/metabolism , RNA, Small Interfering/metabolism , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/therapeutic use , 3T3 Cells , Animals , Base Sequence , Choroid/metabolism , Choroid/pathology , Choroidal Neovascularization/pathology , Disease Models, Animal , Green Fluorescent Proteins/metabolism , Humans , Mice , Mice, Inbred C57BL , Molecular Sequence Data , Retinal Pigment Epithelium/metabolism , Retinal Pigment Epithelium/pathology , Transduction, Genetic , Transfection
9.
Opt Express ; 21(3): 3298-307, 2013 Feb 11.
Article in English | MEDLINE | ID: mdl-23481789

ABSTRACT

We experimentally demonstrate the simultaneous detection of 10-Gbit/s quadrature phase shift keying (QPSK) × 2-channel Fourier-encoded synchronous optical code division multiplexing (FE-SOCDM) signals using a digital coherent receiver, for the first time. First, we analytically verify that simultaneous detection can be achieved with an N-point discrete Fourier transform (DFT) using digital signal processing (DSP) because the N-channel Fourier encoding corresponds to an N × N inverse DFT, then the operation is experimentally confirmed. Simultaneous detection of 10-Gbit/s QPSK × 2-channel FE-SOCDM signals is evaluated. The proposed scheme dramatically expands the capability of OCDM systems.


Subject(s)
Information Storage and Retrieval/methods , Optical Devices , Signal Processing, Computer-Assisted/instrumentation , Telecommunications/instrumentation , Equipment Design , Equipment Failure Analysis , Fourier Analysis
10.
Hum Gene Ther ; 23(4): 399-406, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22133046

ABSTRACT

Hypophosphatasia (HPP), caused by mutations in the gene ALPL encoding tissue-nonspecific alkaline phosphatase (TNALP), is an inherited systemic skeletal disease characterized by mineralization defects of bones and teeth. The clinical severity of HPP varies widely, from a lethal perinatal form to mild odontohypophosphatasia showing only dental manifestations. HPP model mice (Akp2(-/-)) phenotypically mimic the severe infantile form of human HPP; they appear normal at birth but die by 2 weeks of age because of growth failure, hypomineralization, and epileptic seizures. In the present study, we investigated the feasibility of fetal gene therapy using the lethal HPP model mice. On day 15 of gestation, the fetuses of HPP model mice underwent transuterine intraperitoneal injection of adeno-associated virus serotype 9 (AAV9) expressing bone-targeted TNALP. Treated and delivered mice showed normal weight gain and seizure-free survival for at least 8 weeks. Vector sequence was detected in systemic organs including bone at 14 days of age. ALP activities in plasma and bone were consistently high. Enhanced mineralization was demonstrated on X-ray images of the chest and forepaw. Our data clearly demonstrate that systemic injection of AAV9 in utero is an effective strategy for the treatment of lethal HPP mice. Fetal gene therapy may be an important choice after prenatal diagnosis of life-threatening HPP.


Subject(s)
Fetal Therapies , Hypophosphatasia/therapy , Alkaline Phosphatase/genetics , Animals , Disease Models, Animal , Feasibility Studies , Female , Genetic Therapy , Hypophosphatasia/genetics , Mice , Pregnancy , Uterus
11.
Hum Gene Ther ; 22(11): 1355-64, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21388343

ABSTRACT

Hypophosphatasia (HPP) is an inherited disease caused by a deficiency of tissue-nonspecific alkaline phosphatase (TNALP). The major symptom of human HPP is hypomineralization, rickets, or osteomalacia, although the clinical severity is highly variable. The phenotypes of TNALP knockout (Akp2(-/-)) mice mimic those of the severe infantile form of HPP. Akp2(-/-) mice appear normal at birth, but they develop growth failure, epileptic seizures, and hypomineralization and die by 20 days of age. Previously, we have shown that the phenotype of Akp2(-/-) mice can be prevented by enzyme replacement of bone-targeted TNALP in which deca-aspartates are linked to the C-terminus of soluble TNALP (TNALP-D10). In the present study, we evaluated the therapeutic effects of adeno-associated virus serotype 8 (AAV8) vectors that express various forms of TNALP, including TNALP-D10, soluble TNALP tagged with the Flag epitopes (TNALP-F), and native glycosylphosphatidylinositol-anchored TNALP (TNALP-N). A single intravenous injection of 5×10(10) vector genomes of AAV8-TNALP-D10 into Akp2(-/-) mice at day 1 resulted in prolonged survival and phenotypic correction. When AAV8-TNALP-F was injected into neonatal Akp2(-/-) mice, they also survived without epileptic seizures. Interestingly, survival effects were observed in some animals treated with AAV8-TNALP-N. All surviving Akp2(-/-) mice showed a healthy appearance and a normal activity with mature bone mineralization on X-rays. These results suggest that sustained alkaline phosphatase activity in plasma is essential and sufficient for the rescue of Akp2(-/-) mice. AAV8-mediated systemic gene therapy appears to be an effective treatment for the infantile form of human HPP.


Subject(s)
Alkaline Phosphatase/genetics , Dependovirus/genetics , Hypophosphatasia/genetics , Hypophosphatasia/therapy , Alkaline Phosphatase/metabolism , Animals , Animals, Newborn , Cell Line , Genetic Therapy , Humans , Hypophosphatasia/enzymology , Mice , Mice, Knockout , Phenotype
12.
J Bone Miner Res ; 26(1): 135-42, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20687159

ABSTRACT

Hypophosphatasia (HPP) is an inherited systemic skeletal disease caused by mutations in the gene encoding the tissue-nonspecific alkaline phosphatase (TNALP) isozyme. The clinical severity of HPP varies widely, with symptoms including rickets and osteomalacia. TNALP knockout (Akp2(-/-)) mice phenotypically mimic the severe infantile form of HPP; that is, TNALP-deficient mice are born with a normal appearance but die by 20 days of age owing to growth failure, hypomineralization, and epileptic seizures. In this study, a lentiviral vector expressing a bone-targeted form of TNALP was injected into the jugular vein of newborn Akp2(-/-) mice. We found that alkaline phosphatase activity in the plasma of treated Akp2(-/-) mice increased and remained at high levels throughout the life of the animals. The treated Akp2(-/-) mice survived for more than 10 months and demonstrated normal physical activity and a healthy appearance. Epileptic seizures were completely inhibited in the treated Akp2(-/-) mice, and X-ray examination of the skeleton showed that mineralization was significantly improved by the gene therapy. These results show that severe infantile HPP in TNALP knockout mice can be treated with a single injection of lentiviral vector during the neonatal period.


Subject(s)
Alkaline Phosphatase/deficiency , Alkaline Phosphatase/therapeutic use , Genetic Therapy , Hypophosphatasia/genetics , Hypophosphatasia/therapy , Lentivirus/genetics , Alkaline Phosphatase/genetics , Animals , Foot/diagnostic imaging , Hypophosphatasia/diagnostic imaging , Mice , Phenotype , Radiography , Survival Analysis , Tibia/enzymology , Tibia/pathology
13.
Circulation ; 122(9): 910-9, 2010 Aug 31.
Article in English | MEDLINE | ID: mdl-20713899

ABSTRACT

BACKGROUND: We previously identified INT6/eIF3e as a novel regulator of hypoxia-inducible factor 2alpha (HIF2alpha) activity. Small interfering RNA (siRNA)-Int6 adequately stabilized HIF2alpha, even under normoxic conditions, and thereby enhanced the expression of several angiogenic factors in vitro, suggesting that siRNA-Int6 may induce angiogenesis in vivo. METHODS AND RESULTS: We demonstrated a 6- to 8-fold enhanced formation of normal arteries and veins in the subcutaneous regions of adult mice 5 days after a single siRNA-Int6 application. Subcutaneous fibroblasts were identified as the major source of secreted angiogenic factors that led to the formation of functional vessels during Int6 silencing. Fibroblasts transfected ex vivo with siRNA-Int6 induced potent neoangiogenesis when transplanted into a subcutaneous region of nude mice. Application of siRNA-Int6 promoted neoangiogenesis in the area surrounding the injury in wound healing models, including genetically diabetic mice, thereby accelerating the closure of the injury. HIF2alpha accumulation caused by siRNA-Int6 was confirmed as the unequivocal cause of the angiogenesis by an in vivo angiogenesis assay. Further analysis of the Int6 silencing-induced neoangiogenesis revealed that a negative feedback regulation of HIF2alpha stability was caused by HIF2alpha-induced transcription of Int6 via hypoxia-response elements in its promoter. Thus, siRNA-Int6 temporarily facilitates an accumulation of HIF2alpha protein, leading to hypoxia-independent transcription of angiogenic factors and concomitant neoangiogenesis. CONCLUSIONS: We suggest that the pathway involving INT6/HIF2alpha acts as a hypoxia-independent master switch of functional angiogenesis; therefore, siRNA-Int6 application might be of clinical value in treating ischemic diseases such as heart and brain ischemia, skin injury, and diseases involving obstructed vessels.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/genetics , Eukaryotic Initiation Factor-3/genetics , Ischemia/physiopathology , Neovascularization, Physiologic/physiology , Wound Healing/physiology , Actins/metabolism , Animals , Basic Helix-Loop-Helix Transcription Factors/metabolism , Breast Neoplasms , Eukaryotic Initiation Factor-3/metabolism , Feedback, Physiological/physiology , Female , Fibroblasts/physiology , Fibroblasts/transplantation , HeLa Cells , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Ischemia/genetics , Ischemia/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Mutant Strains , Mice, Nude , NIH 3T3 Cells , Platelet Endothelial Cell Adhesion Molecule-1/metabolism , Promoter Regions, Genetic/physiology , RNA, Small Interfering , Signal Transduction/physiology , Subcutaneous Tissue/blood supply , Subcutaneous Tissue/physiology
14.
Biochem Biophys Res Commun ; 350(4): 809-17, 2006 Dec 01.
Article in English | MEDLINE | ID: mdl-17045573

ABSTRACT

The human U6 (hU6) promoter is widely used to express short hairpin RNAs (shRNAs) in mammalian cells. To verify the validity of the generalized concept-the hU6 promoter essentially requires a purine (usually guanine) at +1 for transcription, we enzymatically constructed an arbitrary shRNA library with the following features: (1) to have any one of adenine, cytosine, guanine, and thymine at the site; (2) to comprise shRNAs of 25-30 nucleotides in stem length which are transcribed through the promoter. cDNA of the catalytic subunit of cAMP-dependent protein kinase (PKACalpha) was used as material for library construction. We then used luciferase reporter cell lines to screen shRNAs which effectively reduced PKACalpha activity. Consequently, a purine was mostly present at +2, not at +1, of the clones isolated, suggesting that a purine at +2 rather than +1 adjacent to the hU6 promoter provides effective shRNAs for target gene silencing.


Subject(s)
Kidney/metabolism , Promoter Regions, Genetic/genetics , Purines/metabolism , RNA, Catalytic/biosynthesis , RNA, Catalytic/genetics , RNA, Small Nuclear/genetics , Cell Line , Gene Silencing , Humans , Purines/chemistry , Structure-Activity Relationship
15.
J Ethnopharmacol ; 91(1): 89-94, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15036474

ABSTRACT

We attempted to estimate the pharmacological activity by measuring the concentrations of a composition ingredient using a multivariate statistical analysis method. Medicinal herb of Rhubarb has been many largely unrecognized biochemical and pharmacological effect components. Therefore, we attempted to estimate the antioxidative activity of Rhubarb on low-density lipoprotein (LDL) of its components. Thirty specimens of Rhubarb from various origins were used, chose nine components of anthraquinones, two components of anthrones, two components of flavan-3-ols, one component of procyanidin, one component of naphthalene, two components of phenylbutanones and one component of stilbene. Quantitative analysis of 18 components was performed with high-performance liquid chromatography (HPLC) and antioxidative activities were measured with plasma taken from spontaneous familial hypercholesterolemia model rabbits. There was considerable variation among the specimens in the concentration of components and antioxidative activities on LDL. As a result of multiple regression analysis, significant multiple correlation coefficient for antioxidative activities on LDL (R=0.914, P<0.01) was found in relation to the concentrations of five components: aloe-emodin, chrysophanol, emodin 1-O-beta-D-glucoside, lindleyin and 6-hydroxymusizin 8-O-beta-D-glucoside. Three of the five components were not active in promoting antioxidative activity and there was no significant correlation between the concentrations of the most active component and the activity. We consider this a useful method for selecting of Rhubarb and propose a new scientific approach for the selection of natural medicines.


Subject(s)
Antioxidants/pharmacology , Herbal Medicine/methods , Lipoproteins, LDL/drug effects , Rheum/chemistry , Animals , Antioxidants/chemistry , Chromatography, High Pressure Liquid , Drug Evaluation , Lipoproteins, LDL/blood , Male , Rabbits
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