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1.
JBJS Case Connect ; 14(3)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39058796

RESUMO

CASE: We report a 15-year-old adolescent boy being followed up for 6 years with osteogenesis imperfecta (OI). Genetic testing of this child revealed a novel missense variant c.925C>T p.Arg309Cys in the CREB3L1 gene. Treatment with regular pamidronate therapy showed increased bone mineral density and a reduced fracture rate. His lower limb rush rodding improved his mobility. His withdrawal from bisphosphonate therapy worsened his mobility status but started improving after he restarted treatment, suggesting a response to pamidronate therapy. CONCLUSION: We report a novel biallelic missense variant c.925C>T, p.Arg309Cys, in the CREB3L1 gene causing OI, which responded to bisphosphonate therapy and corrective surgery.


Assuntos
Conservadores da Densidade Óssea , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Osteogênese Imperfeita , Pamidronato , Humanos , Osteogênese Imperfeita/genética , Osteogênese Imperfeita/tratamento farmacológico , Masculino , Pamidronato/uso terapêutico , Adolescente , Conservadores da Densidade Óssea/uso terapêutico , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Difosfonatos/uso terapêutico , Mutação de Sentido Incorreto , Proteínas do Tecido Nervoso
2.
Biomed Pharmacother ; 175: 116725, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38744219

RESUMO

Qualitative alterations in type I collagen due to pathogenic variants in the COL1A1 or COL1A2 genes, result in moderate and severe Osteogenesis Imperfecta (OI), a rare disease characterized by bone fragility. The TGF-ß signaling pathway is overactive in OI patients and certain OI mouse models, and inhibition of TGF-ß through anti-TGF-ß monoclonal antibody therapy in phase I clinical trials in OI adults is rendering encouraging results. However, the impact of TGF-ß inhibition on osteogenic differentiation of mesenchymal stem cells from OI patients (OI-MSCs) is unknown. The following study demonstrates that pediatric skeletal OI-MSCs have imbalanced osteogenesis favoring the osteogenic commitment. Galunisertib, a small molecule inhibitor (SMI) that targets the TGF-ß receptor I (TßRI), favored the final osteogenic maturation of OI-MSCs. Mechanistically, galunisertib downregulated type I collagen expression in OI-MSCs, with greater impact on mutant type I collagen, and concomitantly, modulated the expression of unfolded protein response (UPR) and autophagy markers. In vivo, galunisertib improved trabecular bone parameters only in female oim/oim mice. These results further suggest that type I collagen is a tunable target within the bone ECM that deserves investigation and that the SMI, galunisertib, is a promising new candidate for the anti-TGF-ß targeting for the treatment of OI.


Assuntos
Colágeno Tipo I , Regulação para Baixo , Células-Tronco Mesenquimais , Osteogênese Imperfeita , Osteogênese , Pirazóis , Quinolinas , Osteogênese Imperfeita/genética , Osteogênese Imperfeita/tratamento farmacológico , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Animais , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Regulação para Baixo/efeitos dos fármacos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Feminino , Quinolinas/farmacologia , Camundongos , Criança , Pirazóis/farmacologia , Masculino , Diferenciação Celular/efeitos dos fármacos , Mutação , Modelos Animais de Doenças , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Pré-Escolar , Células Cultivadas , Fator de Crescimento Transformador beta/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
3.
Intern Med ; 63(3): 439-442, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37344433

RESUMO

A 44-year-old man with osteogenesis imperfecta presented with left renal colic. Non-contrast computed tomography revealed a stone (10×9 mm) in the left upper ureter. Ureteroscopic lithotripsy was performed twice and stone-free status was achieved. An analysis of the stone revealed a mixed composition including calcium oxalate and calcium phosphate. Postoperatively, we administered bisphosphonates to prevent recurrence of urolithiasis, as 24-hour urine collection revealed marked hypercalciuria. Eighteen months after surgery, the urinary calcium levels had normalized, and there was no recurrence of urolithiasis. Osteogenesis imperfecta can be complicated by urolithiasis, but bisphosphonates may be useful in preventing recurrence of this disease.


Assuntos
Osteogênese Imperfeita , Urolitíase , Masculino , Humanos , Adulto , Difosfonatos/uso terapêutico , Osteogênese Imperfeita/complicações , Osteogênese Imperfeita/tratamento farmacológico , Urolitíase/complicações , Urolitíase/tratamento farmacológico , Rim , Oxalato de Cálcio/análise , Cálcio
4.
J Pediatr Orthop ; 44(1): e73-e78, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37750572

RESUMO

BACKGROUND: Osteogenesis Imperfecta (OI) usually causes an increased fracture burden and bone deformity, with subsequent operations common. In addition to skeletal manifestations, there is a potential increase in bleeding susceptibility due to the increased frequency of orthopedic procedures, warranting investigation into methods to mitigate this risk. This study aims to evaluate the safety and efficacy of tranexamic acid (TXA) usage to reduce intraoperative blood loss in children with OI. We want to assess the potential benefits, risks, and complications involved with TXA use in this patient population. METHODS: TXA-receiving patients (cases) were matched 1:1 with non-TXA-receiving controls on the following criteria: age within 2 years, bone category, and OI Type. Descriptive statistics were used to summarize the data. Fisher Exact Test was performed to compare transfusion status between groups. A Wilcoxon Rank Sum test was performed to assess differences between the groups in days of stay, length of surgery, and estimated blood loss (EBL). All analyses were conducted using SAS version 9.4. P <0.05 was considered statistically significant. RESULTS: Our TXA-receiving population of 30 patients consisted of 11 females and 19 males. One patient was OI type I, 13 were OI type III, 14 were OI type IV, and 2 were categorized as Other (not Type I through Type IV). We found a significant difference in transfusion status ( P =0.02), with zero TXA patients requiring a transfusion compared with 20% of the control cases. There is also a significant difference in median EBL ( P =0.0004) between groups, with TXA patients having decreased intraoperative EBL (20 vs. 62.5 mL). There was also a difference in median days of postoperative stay between TXA-receiving and non-TXA-receiving patients ( P =0.001; 2.6 vs. 4 d). CONCLUSIONS: Our study concluded that TXA use in OI patients is associated with lower perioperative transfusions and intraoperative blood loss rates. These results support the standard usage of TXA in these patients to reduce intraoperative blood loss. LEVEL OF EVIDENCE: Level III.


Assuntos
Antifibrinolíticos , Osteogênese Imperfeita , Ácido Tranexâmico , Masculino , Criança , Feminino , Humanos , Pré-Escolar , Ácido Tranexâmico/efeitos adversos , Antifibrinolíticos/efeitos adversos , Perda Sanguínea Cirúrgica/prevenção & controle , Osteogênese Imperfeita/tratamento farmacológico , Osteogênese Imperfeita/cirurgia , Transfusão de Sangue
5.
Eur J Med Genet ; 66(11): 104856, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37758163

RESUMO

Osteogenesis imperfecta (OI) and hypophosphatasia (HPP) are rare skeletal disorders caused by mutations in the genes encoding collagen type I (COL1A, COL1A2) and tissue-non-specific isoenzyme of alkaline phosphatase (ALPL), respectively. Both conditions result in skeletal deformities and bone fragility although bone tissue abnormalities differ considerably. Children with OI have low bone mass and hypermineralized matrix, whereas HPP children develop rickets and osteomalacia. We report a family, father and three children, affected with growth retardation, low bone mass and recurrent fractures. None of them had rickets, blue sclera or dentinogenesis imperfecta. ALP serum levels were low and genetics revealed in the four probands heterozygous pathogenic mutations in COL1A2 c.838G > A (p.Gly280Ser) and in ALPL c.1333T > C (p.Ser445Pro). After multidisciplinary meeting, a diagnostic transiliac bone biopsy was indicated for each sibling for therapeutic decision. Bone histology and histomorphometry, as compared to reference values of children with OI type I as well as, to a control pediatric patient harboring the same COL1A2 mutation, revealed similarly decreased trabecular bone volume, increased osteocyte lacunae, but additionally severe osteomalacia. Quantitative backscattered electron imaging demonstrated that bone matrix mineralization was not as decreased as expected for osteomalacia. In summary, we observed within each biopsy samples classical features of OI and classical features of HPP. The apparent nearly normal bone mineralization density distribution results presumably from divergent effects of OI and HPP on matrix mineralization. A combination therapy was initiated with ALP enzyme-replacement and one month later with bisphosphonates. The ongoing treatment led to improved skeletal growth, increased BMD and markedly reduced fracture incidence.


Assuntos
Calcinose , Fraturas Múltiplas , Hipofosfatasia , Osteogênese Imperfeita , Osteomalacia , Raquitismo , Criança , Humanos , Osteogênese Imperfeita/tratamento farmacológico , Osteogênese Imperfeita/genética , Hipofosfatasia/tratamento farmacológico , Hipofosfatasia/genética , Osteomalacia/genética , Osteomalacia/patologia , Mutação , Fosfatase Alcalina/genética
6.
Calcif Tissue Int ; 112(5): 613-620, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36867194

RESUMO

Osteogenesis imperfecta (OI) type VI, a recessively inherited form of OI caused by mutations in SERPINF1, is a severe form distinguished by osteomalacia on bone histomorphometry. We describe a boy with severe OI type VI who was initially treated with intravenous (IV) zoledronic acid (ZA) at 1.4 years of age; however, a year later he transitioned to denosumab 1 mg/kg sub-cutaneously every three months in an effort to decrease fracture rates. After two years on denosumab, he presented with symptomatic hypercalcemia due to the denosumab-induced, hyper-resorptive rebound phenomenon. Laboratory parameters at the time of the rebound were as follows: elevated serum ionized calcium (1.62 mmol/L, N 1.16-1.36), elevated serum creatinine due to hypercalcemia-induced muscle catabolism (83 µmol/L, N 9-55), and suppressed parathyroid hormone (PTH) (< 0.7 pmol/L, N 1.3-5.8). The hypercalcemia was responsive to low-dose IV pamidronate, with a rapid decline in serum ionized calcium, and otherwise normalization of the aforementioned parameters within 10 days. To benefit from the powerful, albeit short-term, anti-resorptive effect of denosumab without further rebound episodes, he was treated thereafter with denosumab 1 mg/kg alternating every three months with IV ZA 0.025 mg/kg. Five years later, he remained on dual alternating anti-resorptive therapy without further rebound episodes, and an overall improvement in his clinical status. This novel pharmacological approach of alternating short- and long-term anti-resorptive therapy every three months has not previously been described. Our report suggests this strategy may be an effective method for prevention of the rebound phenomenon in select children for whom denosumab may be beneficial.


Assuntos
Conservadores da Densidade Óssea , Hipercalcemia , Osteogênese Imperfeita , Criança , Masculino , Humanos , Osteogênese Imperfeita/tratamento farmacológico , Osteogênese Imperfeita/genética , Denosumab , Hipercalcemia/tratamento farmacológico , Cálcio/farmacologia , Densidade Óssea , Ácido Zoledrônico/uso terapêutico
7.
J Clin Endocrinol Metab ; 108(7): 1776-1786, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-36595228

RESUMO

CONTEXT: Mutations in WNT1 can cause rare inherited disorders such as osteogenesis imperfecta (OI) and early-onset osteoporosis (EOOP). Owing to its rarity, the clinical characteristics and pathogenic mechanism of WNT1 mutations remain unclear. OBJECTIVE: We aimed to explore the phenotypic and genotypic spectrum and treatment responses of a large cohort of patients with WNT1-related OI/OP and the molecular mechanisms of WNT1 variants. METHODS: The phenotypes and genotypes of patients and their responses to bisphosphonates or denosumab were evaluated. Western blot analysis, quantitative polymerase chain reaction, and immunofluorescence staining were used to evaluate the expression levels of WNT1, total ß-catenin, and type I collagen in the tibial bone or skin from one patient. RESULTS: We included 16 patients with 16 mutations identified in WNT1, including a novel mutation. The types of WNT1 mutations were related to skeletal phenotypes, and biallelic nonsense mutations or frameshift mutations could lead to an earlier occurrence of fragility fractures and more severe skeletal phenotypes. Some rare comorbidities were identified in this cohort, including cerebral abnormalities, hematologic diseases, and pituitary adenoma. Bisphosphonates and denosumab significantly increased the spine and proximal hip BMD of patients with WNT1 mutations and reshaped the compressed vertebrae. We report for the first time a decreased ß-catenin level in the bone of patient 10 with c.677C > T and c.502G > A compared to the healthy control, which revealed the potential mechanisms of WNT1-induced skeletal phenotypes. CONCLUSION: Biallelic nonsense mutations or frameshift mutations of WNT1 could lead to an earlier occurrence of fragility fractures and a more severe skeletal phenotype in OI and EOOP induced by WNT1 mutations. The reduced osteogenic activity caused by WNT pathway downregulation could be a potential pathogenic mechanism of WNT1-related OI and EOOP.


Assuntos
Fraturas Ósseas , Osteogênese Imperfeita , Osteoporose , Humanos , Osteogênese Imperfeita/tratamento farmacológico , Osteogênese Imperfeita/genética , beta Catenina/genética , Códon sem Sentido , Denosumab , Osteoporose/genética , Genótipo , Fenótipo
8.
Osteoporos Int ; 34(2): 369-377, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36456709

RESUMO

Type V osteogenesis imperfecta (OI) is a form of OI characterized by radial head dislocation (RHD), calcification of interosseous membrane (CIM), and hyperplastic callus (HPC). In this study, we characterized the clinical features of 28 type V OI patients. We presented that dysfunctions of elbow, hip joint, and abnormal epiphyseal growth plate were associated with ectopic calcification and summarized the history of HPC progression and treatment. INTRODUCTION: The current study aims to systematically characterize the skeletal phenotypes of patients with type V OI and suggested possible surgical solutions. METHODS: A total of 28 patients were admitted for inpatient care at The Hong Kong University-Shenzhen Hospital diagnosed with type V OI (either clinically diagnosed or genetically confirmed with the IFITM5 c.-14C > T mutation). RESULTS: Prevalence of type V radiological features was comparable to previous literatures (RHD, 100%; CIM, 100%; HPC, 44%; and scoliosis, 50%). Novel skeletal phenotypes were presented including extension of coronoid process, acetabular labrum, acetabular protrusion, spontaneous autofusion of the hip, bulbous epiphysis, and popcorn calcification. Significant increase in BMD was observed in patients with bisphosphonate treatment. Twenty-five percent (3/12) of patients with preoperative use of indomethacin developed HPC postoperatively, and HPCs were absorbed in 2 young patients 2 years later. CONCLUSION: This retrospective study summarized the clinical features and highlighted the abnormalities in elbow, hip joint, and growth plate in type V OI patients. Our study contributed to a more comprehensive clinical spectrum of type V OI. We also characterized the natural progression of HPC formation and resorption in patients in different ages. The use of bisphosphonate treatment is effective in improving bone mineral density in type V OI patients, and whether indomethacin can reduce incidence of HPC formation deserves further investigation.


Assuntos
Calcinose , Osteogênese Imperfeita , Humanos , Osteogênese Imperfeita/complicações , Osteogênese Imperfeita/tratamento farmacológico , Osteogênese Imperfeita/genética , Estudos Retrospectivos , População do Leste Asiático , Mutação , Difosfonatos/uso terapêutico
9.
J Orthop Res ; 41(4): 808-814, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35803595

RESUMO

Osteogenesis imperfecta (OI) is a genetic bone fragility disorder that features frequent fractures. Bone healing outcomes are contingent on a proper balance between bone formation and resorption, and drugs such as bone morphogenetic proteins (BMPs) and bisphosphonates (BPs) have shown to have utility in modulating fracture repair. While BPs are used for OI to increase BMD and reduce pain and fracture rates, there is little evidence for using BMPs as local agents for fracture healing (alone or with BPs). In this study, we examined wild-type and OI mice (Col1a2+/G610C ) in a murine tibial open fracture model with (i) surgery only/no treatment, (ii) local BMP-2 (10 µg), or (iii) local BMP-2 and postoperative zoledronic acid (ZA; 0.1 mg/kg total dose). Microcomputed tomography reconstructions of healing fractures indicated BMP-2 was less effective in an OI setting, however, BMP-2 +ZA led to considerable increases in bone volume (+193% WT, p < 0.001; +154% OI, p < 0.001) and polar moment of inertia (+125% WT, p < 0.01; +248% OI, p < 0.05). Tissue histology revealed a thinning of the neocortex of the callus in BMP-2 treated OI bone, but considerable retention of woven bone in the healing callus with BMP + ZA specimens. These data suggest a cautious approach may be warranted with the sole application of BMP-2 in an OI surgical setting as a bone graft substitute. However, this may be overcome by off-label BP administration.


Assuntos
Fraturas Ósseas , Osteogênese Imperfeita , Camundongos , Animais , Osteogênese Imperfeita/tratamento farmacológico , Osteogênese Imperfeita/genética , Osteogênese Imperfeita/patologia , Consolidação da Fratura , Microtomografia por Raio-X , Densidade Óssea , Difosfonatos/farmacologia , Calo Ósseo/patologia , Proteínas Morfogenéticas Ósseas/uso terapêutico
10.
BMJ Case Rep ; 15(11)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36343986

RESUMO

Osteogenesis imperfecta is a congenital disease that presents with varying degrees of connective tissue symptoms, including susceptibility to fracture, growth disorders and hearing loss. Here, we discuss a case in which macular neovascularisation (MNV) resulted in metamorphopsia and decreased visual acuity in a patient with osteogenesis imperfecta exhibiting a novel COL1A1 gene mutation (p.Tyr165*). The patient was a woman in her 30s who reported experiencing distorted vision and diminished visual acuity in her right eye for 1 month as well as a history of hearing loss. Rapid improvements in exudative changes and suppression of relapse were achieved after only two intravitreal injections of ranibizumab. Furthermore, since MNV occurred slightly inferior to the fovea centralis, improvements in visual acuity were better than previously reported. As fragility of Bruch's membrane represents the basis of onset, recurrence and relapse are likely in patients exhibiting MNV, highlighting the need for regular follow-up.


Assuntos
Osteogênese Imperfeita , Feminino , Humanos , Osteogênese Imperfeita/complicações , Osteogênese Imperfeita/tratamento farmacológico , Osteogênese Imperfeita/genética , Tomografia de Coerência Óptica , Ranibizumab , Injeções Intravítreas , Recidiva , Mutação , Inibidores da Angiogênese/uso terapêutico
11.
J Bone Miner Res ; 37(5): 826-836, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35306687

RESUMO

Osteogenesis imperfecta (OI) describes a series of genetic bone fragility disorders that can have a substantive impact on patient quality of life. The multidisciplinary approach to management of children and adults with OI primarily involves the administration of antiresorptive medication, allied health (physiotherapy and occupational therapy), and orthopedic surgery. However, advances in gene editing technology and gene therapy vectors bring with them the promise of gene-targeted interventions to provide an enduring or perhaps permanent cure for OI. This review describes emergent technologies for cell- and gene-targeted therapies, major hurdles to their implementation, and the prospects of their future success with a focus on bone disorders. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).


Assuntos
Conservadores da Densidade Óssea , Osteogênese Imperfeita , Adulto , Conservadores da Densidade Óssea/uso terapêutico , Osso e Ossos , Criança , Terapia Genética , Humanos , Osteogênese , Osteogênese Imperfeita/tratamento farmacológico , Osteogênese Imperfeita/terapia , Qualidade de Vida
12.
Calcif Tissue Int ; 110(4): 451-463, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34988594

RESUMO

Hyperplastic callus (HPC) is the most conspicuous features of osteogenesis imperfecta (OI) type V, of which accurate diagnosis and treatment are facing challenges. We investigate the clinical features, and impact factors of HPC in OI type V patients. In this retrospective single-center study, a total of 21 patients with type V OI confirmed by IFITM5 mutation were included. Radiological characteristics of bone were evaluated by X-rays, dual-energy X-ray absorptiometry, and computed tomography scan. Bone biopsy specimens were performed and stained by routine hematoxylin-eosin. The effects of bisphosphonates on HPC were investigated. Eleven patients (52.3%) had HPCs at 19 skeletal sites, 11 of which affected the femur. Three patients developed four (21.1%) HPCs after fractures, and 15 (78.9%) HPCs occurred in absence of bone fracture. The progress of HPCs was variable, of which most HPCs enlarged in the initial phase and remained stable, and only one HPC dwindled in size. One patient had a rapidly growing mass on the right humerus, and biopsy showed irregular trabeculae of woven bone and immature bone and cartilage in the loose and edematous collagenous network without signs of tumor. Bisphosphonates treatment had no significant effects on HPC of OI patients. HPC is the specific characteristic of OI type V patients, and its location, shape, size, and progression are variable, and the femur is the most frequently involved site. It is very important to make a diagnosis of HPC through detecting IFITM5 mutation and completing pathological diagnosis if necessary. The treatment of HPC is worth further exploration.


Assuntos
Osteogênese Imperfeita , Difosfonatos/uso terapêutico , Humanos , Proteínas de Membrana/genética , Osteogênese Imperfeita/tratamento farmacológico , Estudos Retrospectivos
13.
Pediatr Surg Int ; 37(11): 1621-1625, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34374819

RESUMO

PURPOSE: Osteogenesis imperfecta (OI) is a genetic disorder that causes skeletal fragility. For the most fragile infants and young children with OI, intravenous (IV) bisphosphonate administration is essential, but IV access attempts often cause fractures. Port-a-caths help prevent these events, but some surgeons are hesitant to insert these devices in these infants due to lack of data on their safety. METHODS: Retrospective study of pediatric patients with OI who underwent port-a-cath placement from 1999 to 2018; incidence of complications such as infection and thrombosis and need for reoperation or replacement are described. RESULTS: Port-a-caths were placed in 17 patients with OI (median age, 8 mos [5-23 mos]; median weight, 5.8 kg [3.96-9.08 kg]) and remained in place for a median of 53.5 mos (10-127 mos). One port-a-cath was replaced because of thrombosis. Two port-a-caths were removed because of malfunction, one for skin erosion, and one for infection. In these five cases, replacement was not needed because patients could safely tolerate IV access. Two patients have their port-a-cath in place and the remaining ten patients had theirs removed electively as it was no longer needed. CONCLUSION: Port-a-cath placement in pediatric patients with OI is safe and efficacious for durable central access, enabling reliable IV bisphosphonate delivery and reducing iatrogenic trauma.


Assuntos
Osteogênese Imperfeita , Trombose , Dispositivos de Acesso Vascular , Criança , Pré-Escolar , Humanos , Lactente , Infusões Intravenosas , Osteogênese Imperfeita/tratamento farmacológico , Estudos Retrospectivos
14.
Life Sci ; 278: 119628, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34015290

RESUMO

AIM: Osteogenesis imperfecta (OI) is a hereditary connective tissue disorder primarily caused by mutations in COL1A1 or COL1A2, which encode type I collagen. These mutations affect the quantity and/or quality of collagen composition in bones, leading to bone fragility. Currently, there is still a lack of treatment that addresses disease-causing factors due to an insufficient understanding of the pathological mechanisms involved. MAIN METHODS: Induced pluripotent stem cells (iPSCs) were generated from OI patients with glycine substitution mutations in COL1A1 and COL1A2 and developed into mesenchymal stem cells (iPS-MSCs). OI-derived iPS-MSCs underwent in vitro osteogenic induction to study cell growth, osteogenic differentiation capacity, mRNA expression of osteogenic and unfolded protein response (UPR) markers and apoptosis. The effects of 4-phenylbutyric acid (4-PBA) were examined after treatment of OI iPS-MSCs during osteogenesis. KEY FINDINGS: OI-derived iPS-MSCs exhibited decreased cell growth and impaired osteogenic differentiation and collagen expression. Expression of UPR genes was increased, which led to an increase in apoptotic cell death. 4-PBA treatment decreased apoptotic cells and reduced expression of UPR genes, including HSPA5, XBP1, ATF4, DDIT3, and ATF6. Osteogenic phenotypes, including RUNX2, SPP1, BGLAP, and IBPS expression, as well as calcium mineralization, were also improved. SIGNIFICANCE: MSCs differentiated from disease-specific iPSCs have utility as a disease model for identifying disease-specific treatments. In addition, the ER stress-associated UPR could be a pathogenic mechanism associated with OI. Treatment with 4-PBA alleviated OI pathogenesis by attenuating UPR markers and apoptotic cell death.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese Imperfeita/tratamento farmacológico , Osteogênese/efeitos dos fármacos , Fenilbutiratos/farmacologia , Apoptose/efeitos dos fármacos , Células Cultivadas , Chaperona BiP do Retículo Endoplasmático , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Osteogênese Imperfeita/metabolismo , Osteogênese Imperfeita/patologia , Resposta a Proteínas não Dobradas/efeitos dos fármacos
15.
Bone ; 148: 115914, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33722772

RESUMO

Osteogenesis imperfecta (OI) is a disease characterised by altered bone tissue material properties together with abnormal micro and macro-architecture and thus bone fragility, increased bone turnover and hyperosteocytosis. Increasingly appreciated are the soft tissue changes, sarcopenia in particular. Approaches to treatment are now multidisciplinary, with bisphosphonates having been the primary pharmacological intervention over the last 20 years. Whilst meta-analyses suggest that anti-fracture efficacy across the life course is equivocal, there is good evidence that for children bisphosphonates reduce fracture risk, increase vertebral size and improve vertebral shape, as well as improving motor function and mobility. The genetics of OI continues to provide insights into the molecular pathogenesis of the disease, although the pathophysiology is less clear. The complexity of the multi-scale interactions of bone tissue with cellular function are gradually being disentangled, but the fundamental question of why increased tissue brittleness should be associated with so many other changes is unclear; ER stress, pro-inflammatory cytokines, accelerated senesence and altered matrix component release might all contribute, but a unifying hypothesis remains elusive. New approaches to therapy are focussed on increasing bone mass, following the paradigm established by the treatment of postmenopausal osteoporosis. For adults, this brings the prospect of restoring previously lost bone - for children, particularly at the severe end of the spectrum, the possibility of further reducing fracture frequency and possibly altering growth and long term function are attractive. The alternatives that might affect tissue brittleness are autophagy enhancement (through the removal of abnormal type I collagen aggregates) and stem cell transplantation - both still at the preclinical stage of assessment. Preclinical assessment is not supportive of targeting inflammatory pathways, although understanding why TGFb signalling is increased, and whether that presents a treatment target in OI, remains to be established.


Assuntos
Fraturas Ósseas , Osteogênese Imperfeita , Adulto , Densidade Óssea , Osso e Ossos , Criança , Difosfonatos/uso terapêutico , Humanos , Osteogênese Imperfeita/tratamento farmacológico
16.
Curr Osteoporos Rep ; 19(3): 264-270, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33646506

RESUMO

PURPOSE OF REVIEW: The purpose of this review is to precise the indications for intramedullary rodding of long bones in osteogenesis imperfecta, the classic treatment for fractures and deformities in this condition. RECENT FINDINGS: The use of plates and screws alone is not recommended, but its use in conjunction with rodding is becoming more popular as demonstrated in recent literature. The different types of rods are reviewed and their advantages/disadvantages exposed. There is a clear advantage for telescopic rods in terms of incidence of revision surgery but complications are still to be expected. An interdisciplinary approach combining a medical treatment with a surgical correction of deformities as well as a rehabilitation program is the key for success in the treatment of osteogenesis imperfecta children.


Assuntos
Fixação Intramedular de Fraturas/métodos , Fraturas Ósseas/etiologia , Fraturas Ósseas/cirurgia , Osteogênese Imperfeita/complicações , Osteogênese Imperfeita/cirurgia , Braquetes , Criança , Pré-Escolar , Difosfonatos/uso terapêutico , Humanos , Lactente , Fixadores Internos , Osteogênese Imperfeita/tratamento farmacológico , Reoperação
17.
BMJ Case Rep ; 14(2)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33542026

RESUMO

Osteogenesis imperfecta (OI) consists of a group of genetically and phenotypically heterogeneous diseases characterised by bone fragility. Recent improvement in gene sequencing methods has helped us identify rare forms of OI that are inherited in an autosomal recessive manner. Paediatric endocrinology was consulted on a newborn girl with multiple fractures and wavy thin ribs noted on X-rays. In addition to the bone phenotype, she also has short stature and recurrent acute liver failure (ALF) episodes triggered by intercurrent illness. Whole exome sequencing revealed two novel compound heterozygous variants in neuroblastoma amplified sequence (NBAS) gene. NBAS gene codes for a protein that is involved in nonsense-mediated decay pathway and retrograde transport of proteins from Golgi to endoplasmic reticulum. Recognition of pathogenic variants in this gene as a rare cause of autosomal recessive OI and recurrent ALF has important therapeutic implications.


Assuntos
Heterozigoto , Falência Hepática Aguda/genética , Proteínas de Neoplasias/genética , Osteogênese Imperfeita/genética , Conservadores da Densidade Óssea/uso terapêutico , Nanismo/genética , Feminino , Humanos , Lactente , Recém-Nascido , Osteogênese Imperfeita/tratamento farmacológico , Pamidronato/uso terapêutico , Fenótipo , Recidiva , Sequenciamento do Exoma
18.
J Pediatr Endocrinol Metab ; 33(11): 1391-1397, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33031051

RESUMO

Objectives Osteogenesis imperfecta (OI) is a skeletal dysplasia characterized by recurrent fractures due to congenital bone fragility. The only bisphosphonate approved for OI in Japan is pamidronate (PAM). To investigate whether monthly intravenous alendronate (ALN) infusions can maintain bone strength in OI children following cyclical PAM treatment. Methods A prospective and non-inferiority study was conducted. Eight school-age OI patients aged 8.5±2.0 years who were treated with cyclical PAM for 6.0±2.3 years were enrolled and switched to monthly intravenous ALN (0.030 mg/kg/month). Changes in L1-4 bone mineral density (BMD) Z-scores, fracture rates, and bone turnover markers for 12 months were analyzed. Results Average BMD Z-scores were -3.0±1.9, -2.9±2.0, and -2.2±2.0 in 12 months before enrollment, at enrollment, and after 12 months of ALN treatment, respectively. BMD Z-scores increased significantly during treatment with both PAM and ALN (p=0.012), and the effect of ALN was not inferior to that of PAM (p=0.67). There was no change in fracture rates (p=0.86) and bone turnover markers during the 12 months before and after enrollment. Additionally, ALN showed no remarkable side effects. Conclusions Our results suggest that monthly intravenous ALN can maintain bone strength after primary usage of cyclical PAM. We concluded that monthly intravenous ALN as a maintenance treatment following cyclical PAM administration can be an option for OI children.


Assuntos
Alendronato/administração & dosagem , Osteogênese Imperfeita/tratamento farmacológico , Pamidronato/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/administração & dosagem , Criança , Pré-Escolar , Esquema de Medicação , Quimioterapia Combinada , Estudos de Equivalência como Asunto , Feminino , Humanos , Lactente , Recém-Nascido , Infusões Intravenosas , Japão , Quimioterapia de Manutenção/métodos , Masculino , Osteogênese Imperfeita/metabolismo , Osteogênese Imperfeita/fisiopatologia , Resultado do Tratamento
19.
Curr Osteoporos Rep ; 18(5): 486-504, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32960409

RESUMO

PURPOSE OF REVIEW: The goal of this systematic review is to analyze the effectiveness of bisphosphonates (BPs) to treat bone pain in children and adolescents who have diseases with skeletal involvement. RECENT FINDINGS: We included 24 studies (2 randomized controlled trials, 3 non-randomized controlled trials, 10 non-randomized open-label uncontrolled studies, 8 retrospective studies, and 1 study with design not specified). The majority of included studies assessed pain from a unidimensional approach, with pain intensity the most frequently evaluated dimension. Only 38% of studies used validated tools; visual analogue scale was the most frequently employed. BPs were used to alleviate bone pain in a wide variety of pediatrics conditions such as osteogenesis imperfecta, secondary osteoporosis, osteonecrosis related to chemotherapy, chronic non-bacterial osteitis, idiopathic juvenile osteoporosis, unresectable benign bone tumor, and cancer-related pain. Twenty of the 24 studies reported a positive effect of BPs for alleviating pain in different pathologies, but 58% of the studies were categorized as having high risk of bias. Intravenous BPs are helpful in alleviating bone pain in children and adolescents. It is advised that our results be interpreted with caution due to the heterogeneity of the doses used, duration of treatments, and types of pathologies included. In addition, this review shows the paucity of high-quality evidence in the available literature and further research is needed. TRIAL REGISTRATION: Before the completion of this review, the protocol was registered to PROSPERO (International prospective register of systematic reviews), PROSPERO 2020 ID # CRD42020158316. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020158316.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Dor do Câncer/tratamento farmacológico , Difosfonatos/uso terapêutico , Dor/tratamento farmacológico , Antineoplásicos/efeitos adversos , Neoplasias Ósseas/complicações , Neoplasias Ósseas/tratamento farmacológico , Criança , Humanos , Osteíte/complicações , Osteíte/tratamento farmacológico , Osteogênese Imperfeita/complicações , Osteogênese Imperfeita/tratamento farmacológico , Osteonecrose/induzido quimicamente , Osteonecrose/complicações , Osteonecrose/tratamento farmacológico , Osteoporose/complicações , Osteoporose/tratamento farmacológico , Dor/etiologia , Manejo da Dor , Medição da Dor , Resultado do Tratamento
20.
Orthop Surg ; 12(4): 1293-1303, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32589343

RESUMO

OBJECTIVE: To assess the effectiveness and safety of oral bisphosphonates in increasing bone mineral density (BMD), reducing fractures, and improving clinical function in patients with osteogenesis imperfecta (OI). METHODS: Studies were eligible for inclusion if they were randomized controlled trials of directly comparing oral bisphosphonate therapy with placebo-group in OI patients. Data synthesis regarding to bone mineral density as measured by dual-energy X-ray absorptiometry (DEXA), decreased fracture incidence, change in biochemical markers of bone and mineral metabolism, bone histology, growth, bone pain, quality of life, and others were assessed, and meta-analysis done when possible. RESULTS: From 98 potential references and six randomized controlled studies a total of 263 participants receiving oral bisphosphonates and 143 placebo treatments contributed data to meta-analysis. Pooled meta-analysis of three studies suggested that there was significant difference between bisphosphonate treated group and placebo in number of patients with at least one fracture (mean difference 0.53, 95% confidence interval 0.32-0.89, P = 0.02). Pooled meta-analysis of two studies suggested that significant difference was noted between bisphosphonate treated group and placebo in mean percentage change in spine BMD (T-score) (mean difference 28.43, 95% confidence interval 7.09-49.77, P = 0.009). The similar effect was shown in the term of mean change (Z-score) in spine BMD. CONCLUSIONS: Significant improvement in lumbar areal BMD in patients affected with OI has been shown when treated with oral bisphosphonates, even though only a small population was enrolled. We cannot draw a definite conclusion that the increase in BMD can be translated into fracture reduction and clinical functional improvement. The optimal method, dose, type, initiation, and duration of oral bisphosphonates therapy still remains unclear. Well-designed, adequately-powered, placebo-controlled RCTs investigating the effects of oral bisphosphonates on fractures reduction and improvement in quality of life in both children and adults are studied here.


Assuntos
Densidade Óssea/efeitos dos fármacos , Difosfonatos/uso terapêutico , Fraturas Ósseas/prevenção & controle , Osteogênese Imperfeita/tratamento farmacológico , Conservadores da Densidade Óssea/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
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