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Bone & Joint Research
Vol. 7, Issue 2 | Pages 139 - 147
1 Feb 2018
Takahara S Lee SY Iwakura T Oe K Fukui T Okumachi E Waki T Arakura M Sakai Y Nishida K Kuroda R Niikura T

Objectives

Diabetes mellitus (DM) is known to impair fracture healing. Increasing evidence suggests that some microRNA (miRNA) is involved in the pathophysiology of diabetes and its complications. We hypothesized that the functions of miRNA and changes to their patterns of expression may be implicated in the pathogenesis of impaired fracture healing in DM.

Methods

Closed transverse fractures were created in the femurs of 116 rats, with half assigned to the DM group and half assigned to the control group. Rats with DM were induced by a single intraperitoneal injection of streptozotocin. At post-fracture days five, seven, 11, 14, 21, and 28, miRNA was extracted from the newly generated tissue at the fracture site. Microarray analysis was performed with miRNA samples from each group on post-fracture days five and 11. For further analysis, real-time polymerase chain reaction (PCR) analysis was performed at each timepoint.


The Bone & Joint Journal
Vol. 97-B, Issue 8 | Pages 1144 - 1151
1 Aug 2015
Waki T Lee SY Niikura T Iwakura T Dogaki Y Okumachi E Kuroda R Kurosaka M

MicroRNAs (miRNAs ) are small non-coding RNAs that regulate gene expression. We hypothesised that the functions of certain miRNAs and changes to their patterns of expression may be crucial in the pathogenesis of nonunion. Healing fractures and atrophic nonunions produced by periosteal cauterisation were created in the femora of 94 rats, with 1:1 group allocation. At post-fracture days three, seven, ten, 14, 21 and 28, miRNAs were extracted from the newly generated tissue at the fracture site. Microarray and real-time polymerase chain reaction (PCR) analyses of day 14 samples revealed that five miRNAs, miR-31a-3p, miR-31a-5p, miR-146a-5p, miR-146b-5p and miR-223-3p, were highly upregulated in nonunion. Real-time PCR analysis further revealed that, in nonunion, the expression levels of all five of these miRNAs peaked on day 14 and declined thereafter.

Our results suggest that miR-31a-3p, miR-31a-5p, miR-146a-5p, miR-146b-5p and miR-223-3p may play an important role in the development of nonunion. These findings add to the understanding of the molecular mechanism for nonunion formation and may lead to the development of novel therapeutic strategies for its treatment.

Cite this article: Bone Joint J 2015; 97-B:1144–51.


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_11 | Pages 350 - 350
1 Jul 2014
Lee S Okumachi E Dogaki Y Niikura T Iwakura T Waki T Nishida K Kurosaka M
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Summary Statement

Low-intensity pulsed ultrasound (LIPUS) enhanced osteogenic differentiation of osteoprogenitor cells derived from mouse induced pluripotent cells (iPSCs) without embryoid body formation. Our findings provide insights on the development of LIPUS as an effective technology for bone regeneration strategies using iPSCs.

Introduction

iPSCs represent a promising cell source for regenerative medicine such as bone regeneration because of their unlimited self-renewal property and ability of differentiation into all somatic cell types. Recently, we developed an efficient protocol for generating a highly homogeneous population of osteoprogenitor cells from embryonic stem cells by using a direct-plating method without EB formation step. It is well-recognised that LIPUS accelerates the fracture healing. There have been several reports showing that LIPUS stimulates the osteogenic differentiation of mesenchymal stem cells (MSCs) in vitro. To date, effect of LIPUS on iPSCs remains unknown. In this study, we investigated in vitro effect of LIPUS on osteogenic differentiation of osteoprogenitor cells derived from mouse iPS cells via a direct-plating method.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 34 - 34
1 Apr 2013
Koga T Niikura T Lee SY Dogaki Y Okumachi E Waki T Ueha T Sakai Y Oe K Miwa M Kurosaka M
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Introduction

It is well known that blood flow is a critical key component of fracture repair. Previously, we demonstrated that transcutaneous application of CO2 increased blood flow in the human body. To date, there has been no report investigating the effect of the carbonated therapy on fracture repair.

Hypothesis

We hypothesized that the transcutaneous application of CO2 to fracture site would accelerate fracture repair.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 91 - 91
1 Apr 2013
Okumachi E Lee SY Niikura T Koga T Dogaki Y Waki T Kurosaka M
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Introduction

Recently, some case reports have been published, in which nonunions were successfully healed with parathyroid hormone 1–34 (PTH) administration. Previously, we demonstrated that the intervening tissue at the nonunion site contains multilineage mesenchymal progenitor cells and plays an important role during the healing process of nonunion. We investigated the effect of PTH on osteogenic differentiation of human nonunion tissue-derived cells (NCs) in vitro.

Hypothesis

We hypothesized that PTH directly promoted osteogenic differentiation of NCs.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 32 - 32
1 Apr 2013
Lee S Niikura T Koga T Dogaki Y Okumachi E Waki T Kurosaka M
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Introduction

Low-intensity pulsed ultrasound (LIPUS) has been reported to enhance healing of fracture and nonunion. Bone morphogenetic protein-7 (BMP-7) has also been reported to promote bone formation. Recently, we demonstrated progenitor cells with osteogenic/chondrogenic differentiation potential existed in human fracture hematoma and nonunion tissue.

Hypothesis

We hypothesised the combined application of LIPUS and BMP-7 would cause major effect on osteogenesis of hematoma-derived cells (HCs) and nonunion tissue-derived cells (NCs).


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 84 - 84
1 Apr 2013
Koga T Niikura T Lee SY Dogaki Y Okumachi E Waki T Kurosaka M
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Introduction

The hematoma occurring at a fracture site is known to play an important role in fracture healing. Previously, we demonstrated that fracture hematoma contained multilineage mesenchymal progenitor cells. On the other hand, the process of fracture healing is associated by two different mechanisms, intramembranous and endochondral. However, there are no reports proving the details about cellular analysis in the process of endochondoral ossification.

Hypothesis

We hypothesized that one of the cell origins for endochondral ossification after fracture was hematoma.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 56 - 56
1 Apr 2013
Dogaki Y Niikura T Lee S Koga T Okumachi E Waki T Kurosaka M
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Introduction

Our previous study using microarray analysis showed that Rad (Ras associated with diabetes) was highly expressed in nonunion. The purpose of this study is to investigate the gene expression and immunolocalization of Rad, and other Ras-related G proteins: Rem1 and Rem2 in fracture/nonunion site using rat experimental models.

Hypothesis

We hypothesized that Rad had a significant role in nonunion formation.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 80 - 80
1 Apr 2013
Dogaki Y Lee S Niikura T Koga T Okumachi E Waki T Kakutani K Nishida K Kurosaka M
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Introduction

iPSCs represent a promising cell source for bone regeneration. To generate osteoprogenitor cells, most protocols use the generation of embryoid bodies (EBs). However, these protocols give rise to heterogeneous population of different cell lineage.

Hypothesis

We hypothesized that a direct plating method without EB formation step could be an efficient protocol for generating a homogeneous population of osteoprogenitor cells from iPSCs.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 82 - 82
1 Apr 2013
Dogaki Y Lee S Niikura T Koga T Okumachi E Waki T Kurosaka M
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Introduction

Parathyroid hormone 1–34 (PTH) has been reported to accelerate fracture healing. Previously, we demonstrated human fracture hematoma contained osteo-/chondro-progenitor cells. To date, there has been no study investigating the effect of PTH on fracture hematoma-derived cells (HCs) in vitro.

Hypothesis

We hypothesized PTH treatment affected osteogenesis and chondrogenesis of HCs.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 28 - 28
1 Apr 2013
Niikura T Lee SY Koga T Dogaki Y Okumachi E Waki T Kurosaka M
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Introduction

Many surgeons assess biological activity of fracture nonunion by the presence or absence of callus using radiograph. However, it is difficult to assess biological activity only by radiographic appearance. Bone scintigraphy reflects blood supply and bone metabolism and is possibly useful to assess biological activity in nonunion cases.

Hypothesis

We hypothesized that poor callus visualization did not always mean lack of biological activity.