1,249 research outputs found

    Human collagen Krox up-regulates type I collagen expression in normal and scleroderma fibroblasts through interaction with Sp1 and Sp3 transcription factors.

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    Despite several investigations, the transcriptional mechanisms that regulate the expression of both type I collagen genes (COL1A1 and COL1A2) in either physiological or pathological situations, such as scleroderma, are not completely known. We have investigated the role of hc-Krox transcription factor on type I collagen expression by human dermal fibroblasts. hc-Krox exerted a stimulating effect on type I collagen protein synthesis and enhanced the corresponding mRNA steady-state levels of COL1A1 and COL1A2 in foreskin fibroblasts (FF), adult normal fibroblasts (ANF), and scleroderma fibroblasts (SF). Forced hc-Krox expression was found to up-regulate COL1A1 transcription through a -112/-61-bp sequence in FF, ANF, and SF. Knockdown of hc-Krox by short interfering RNA and decoy strategies confirmed the transactivating effect of hc-Krox and decreased substantially COL1A1 transcription levels in all fibro-blast types. The -112/-61-bp sequence bound specifically hc-Krox but also Sp1 and CBF. Attempts to elucidate the potential interactions between hc-Krox, Sp1, and Sp3 revealed that all of them co-immunoprecipitate from FF cellular extracts when a c-Krox antibody was used and bind to the COL1A1 promoter in chromatin immunoprecipitation assays. Moreover, hc-Krox DNA binding activity to its COL1A1-responsive element is increased in SF, cells producing higher amounts of type I collagen compared with ANF and FF. These data suggest that the regulation of COL1A1 gene transcription in human dermal fibroblasts involves a complex machinery that implicates at least three transcription proteins, hc-Krox, Sp1, and Sp3, which could act in concert to up-regulate COL1A1 transcriptional activity and provide evidence for a pro-fibrotic role of hc-Krox

    Genotype-phenotype correlation study in 364 osteogenesis imperfecta Italian patients

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    Osteogenesis imperfecta (OI) is a rare genetic disorder of the connective tissue and 90% of cases are due to dominant mutations in COL1A1 and COL1A2 genes. To increase OI disease knowledge and contribute to patient follow-up management, a homogeneous Italian cohort of 364 subjects affected by OI types I-IV was evaluated. The study population was composed of 262 OI type I, 24 type II, 39 type III, and 39 type IV patients. Three hundred and nine subjects had a type I collagen affecting function mutations (230 in α1(I) and 79 in α2(I)); no disease-causing changes were noticed in 55 patients. Compared with previous genotype-phenotype OI correlation studies, additional observations arose: a new effect for α1- and α2-serine substitutions has been pointed out and heart defects, never considered before, resulted associated to quantitative mutations (P = 0.043). Moreover, some different findings emerged if compared with previous literature; especially, focusing the attention on the lethal form, no association with specific collagen regions was found and most of variants localized in the previously reported "lethal clusters" were causative of OI types I-IV. Some discrepancies have been highlighted also considering the "50-55 nucleotides rule," as well as the relationship between specific collagen I mutated region and the presence of dentinogenesis imperfecta and/or blue sclera. Despite difficulties still present in defining clear rules to predict the clinical outcome in OI patients, this study provides new pieces for completing the puzzle, also thanks to the inclusion of clinical signs never considered before and to the large number of OI Italian patients

    Rapid Growth of Dermatofibrosarcoma Protuberans Associated with Bilateral Adrenalectomy for Cushing's Syndrome

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    We describe a 50-year-old Japanese patient with dermatofibrosarcoma protuberans (DFSP) rapidly growing after bilateral adrenalectomy for Cushing's syndrome that reduced the serum level of cortisol from 17.1 to 0.8 mg/dl. It is known that glucocorticoids decrease the transcriptions of the COL1A1 gene and the PDGFB gene, which is under the direct control of the COL1A1 gene in most DFSP. Therefore, the hypersecretion of glucocorticoids in Cushing's syndrome might suppress the development of DFSP. To the best of our knowledge, this is the first case of rapid growth of DFSP that may be associated with bilateral adrenalectomy for Cushing's syndrome

    Enhanced osteogenic differentiation in zoledronate-treated osteoporotic patients

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    Bisphosphonates are well known inhibitors of osteoclast activity and thus may be employed to influence osteoblast activity. The present study was designed to evaluate the in vivo effects of zoledronic acid (ZA) on the proliferation and osteoblastic commitment of mesenchymal stem cells (MSC) in osteoporotic patients. We studied 22 postmenopausal osteoporotic patients. Densitometric, biochemical, cellular and molecular data were collected before as well as after 6 and 12 months of ZA treatment. Peripheral blood MSC-like cells were quantified by colony-forming unit fibroblastic assay; their osteogenic differentiation potential was evaluated after 3 and 7 days of induction, respectively. Circulating MSCs showed significantly increased expression levels of osteoblastic marker genes such as Runt-related transcription factor 2 (RUNX2), and Osteonectin (SPARC) during the 12 months of monitoring time. Lumbar bone mineral density (BMD) variation and SPARC gene expression correlated positively. Bone turnover marker levels were significantly lowered after ZA treatment; the effect was more pronounced for C terminal telopeptide (CTX) than for Procollagen Type 1 N-Terminal Propeptide (P1NP) and bone alkaline phosphatase (bALP). Our findings suggest a discrete anabolic activity supported by osteogenic commitment of MSCs, consequent to ZA treatment. We confirm its anabolic effects in vivo on osteogenic precursors

    Pregnancies complicated by maternal osteogenesis imperfecta type III: a case report and review of literature.

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    The restrictive lung disease can be exacerbated by growing fundus in women with osteogenesis imperfecta type III. Regional anesthesia can be performed in these women. Mode of delivery for women with osteogenesis imperfecta type III is generally cesarean delivery. Neonatal outcomes are complicated due to indicated preterm deliveries

    Whole-exome sequencing identifies de novo mutation in the COL1A1 gene to underlie the severe osteogenesis imperfecta

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    Background Osteogenesis imperfecta (OI) comprises a clinically and genetically heterogeneous group of connective tissue disorders, characterized by low bone mass, increased bone fragility, and blue-gray eye sclera. OI often results from missense mutations in one of the conserved glycine residues present in the Gly-X-Y sequence repeats of the triple helical region of the collagen type I α chain, which is encoded by the COL1A1 gene. The aim of the present study is to describe the phenotype of OI II patient and a novel mutation, causing current phenotype. Results We report an undescribed de novo COL1A1 mutation in a patient affected by severe OI. After performing the whole-exome sequencing in a case parent–child trio, we identified a novel heterozygous c.2317G > T missense mutation in the COL1A1 gene, which leads to p.Gly773Cys transversion in the triple helical domain of the collagen type I α chain. The presence of the missense mutation was confirmed with the Sanger sequencing. Conclusions Hereby, we report a novel mutation in the COL1A1 gene causing severe, life threatening OI and indicate the role of de novo mutation in the pathogenesis of rare familial diseases. Our study underlines the importance of exome sequencing in disease gene discovery for families where conventional genetic testing does not give conclusive evidence

    Polimorfizm genu kodującego łańcuch α-1 kolagenu typu I a ryzyko wystąpienia defektu statyki narządów dna miednicy mniejszej – wyniki wstępne

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    Introduction: Polymorphism of the gene encoding α-1 chain of type I collagen (COL1A1) may influence the mechanical properties of the pelvic floor connective tissue. Aim of study: We examined possible role of G→T substitution in transcription factor Sp1 binding site in the gene encoding α-1 chain of type I collagen (COL1A1) in the development of pelvic organ prolapse. Materials and methods: The study group consisted of 37 women with pelvic floor defects graded according POPQ scale as stage II, III and IV. All study group patients underwent reconstructive surgery of the pelvic floor. We enrolled forty control subjects. All of them were treated for benign gynecological conditions other then stress urinary incontinence or pelvic organ prolapse. DNA was obtained from peripheral blood leukocytes. The fragment of the first intron of COL1A1 gene containing Sp1 binding site was amplified by PCR and analysis of restriction fragment length polymorphism was done. Results: The GG polymorphism in COL1A1 gene was identified in 26 (70.3%), GT sequence in 10 (27%) and TT in 1 (2.7%) patient. The distribution of the investigated polymorphisms in the control group were: 27 (67.5%), 9 (22.5%) and 4 (10%), respectively. We do not found association between investigated polymorphic variants and pelvic organ prolapse (chi2 test, p=ns). Conclusion: G→T substitution in transcription factor Sp1 binding site in the COLIA1 gene does not increase the risk of development of pelvic floor defect (POPQ stages II, III, IV).Wstęp: Polimorfizm genu kodującego łańcuch α-1 kolagenu typu I (COL1A1) może mieć wpływ na właściwości mechaniczne tkanki łącznej, z której zbudowane są powięzie dna miednicy mniejszej. Cel badania: Celem badania było ustalenie, czy istnieje związek między typami polimorfizmu miejsca wiązania czynnika transkrypcyjnego Sp-1 genu dla COL1A1 a ryzykiem wystąpienia defektów statyki narządów dna miednicy mniejszej. Materiał i metodyka: Grupa badana liczyła 37 pacjentek hospitalizowanych z powodu zaburzeń statyki określanych w skali POPQ jako stopień II, III lub IV. Pacjentki zostały poddane leczeniu chirurgicznemu korygującemu zaburzenia statyki narządu płciowego. Grupa kontrolna: 40 kobiet ze schorzeniami nienowotworowymi, bez zaburzeń statyki (stopień 0, I POPQ) i nietrzymania moczu. Od każdej pacjentki pobrano 5 ml krwi, z której izolowano DNA. Następnie przeprowadzano reakcję amplifikacji z użyciem specyficznych dla badanego miejsca genomu starterów (fragment pierwszego intronu genu COL1A1). Wyniki: Polimorfizm genu COL1A1 typu GG zidentyfikowano u 26 (70,3%), GT u 10 (27%), zaś TT u 1 (2,7%) pacjentki. W grupie kontrolnej dystrybucja polimorfizmów była następująca: GG 27 (67,5%), GT 9 (22,5%) TT 4 (10%). Nie wykazano istotnych różnic w częstości występowania typów polimorfizmu między porównywanymi grupami (chi2 test, p=ns). Wnioski: Wyniki wskazują, że substytucja typu G→T w obrębie miejsca wiązania czynnika transkrypcyjnego Sp-1 zlokalizowanego w obrębie promotora genu COL1A1 nie wpływa na ryzyko wystąpienia defektu statyki narządu rodnego (POPQ II, III, IV)

    Mutation analysis of the <i>COL1A1</i> and <i>COL1A2</i> genes in Vietnamese patients with osteogenesis imperfecta

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    BackgroundThe genetics of osteogenesis imperfecta (OI) have not been studied in a Vietnamese population before. We performed mutational analysis of the COL1A1 and COL1A2 genes in 91 unrelated OI patients of Vietnamese origin. We then systematically characterized the mutation profiles of these two genes which are most commonly related to OI.MethodsGenomic DNA was extracted from EDTA-preserved blood according to standard high-salt extraction methods. Sequence analysis and pathogenic variant identification was performed with Mutation Surveyor DNA variant analysis software. Prediction of the pathogenicity of mutations was conducted using Alamut Visual software. The presence of variants was checked against Dalgleish's osteogenesis imperfecta mutation database.ResultsThe sample consisted of 91 unrelated osteogenesis imperfecta patients. We identified 54 patients with COL1A1/2 pathogenic variants; 33 with COL1A1 and 21 with COL1A2. Two patients had multiple pathogenic variants. Seventeen novel COL1A1 and 10 novel COL1A2 variants were identified. The majority of identified COL1A1/2 pathogenic variants occurred in a glycine substitution (36/56, 64.3 %), usually serine (23/36, 63.9 %). We found two pathogenic variants of the COL1A1 gene c.2461G > A (p.Gly821Ser) in four unrelated patients and one, c.2005G > A (p.Ala669Thr), in two unrelated patients.ConclusionOur data showed a lower number of collagen OI pathogenic variants in Vietnamese patients compared to reported rates for Asian populations. The OI mutational profile of the Vietnamese population is unique and related to the presence of a high number of recessive mutations in non-collagenous OI genes. Further analysis of OI patients negative for collagen mutations, is required

    Infantile cortical hyperostosis and COL1A1 mutation in four generations

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    Infantile cortical hyperostosis (ICH, OMIM 114000) is a rare familial disorder which affects infants. It spontaneously heals in the first years of life. The disease is characterized by regressive subperiosteal hyperosteogenesis mainly affecting long bones, mandible, clavicles, and ribs which are remarkably swollen and deformed on X-rays. But it is also important to take into consideration the autosomal dominant pattern of inheritance to detect it. In 2005 Gensure et al. detected 3040C→T mutation in COL1A1 gene in three unrelated ICH families. Four generations of patients belonging to the same family were examined in our study. Molecular testing has now disclosed a pathogenic mutation in nine of them. The patients spontaneously recovered. Although our paper shows a distinct correlation between R836C mutation and ICH, there is a certain interindividual and intra-familial variability
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