Functional block of IL-17 cytokine promotes bone healing by augmenting FOXO1 and ATF4 activity in cortical bone defect model

SummaryA 10 mm-long (Group #1) or 20 mmlong (Group #2) segmental osteoperiosteal defect was performed on the metatarsus of ten adult ewes (5+5). The goal of the study was to search for a critical size defect model leading to nonunion. The bone gap was maintained for three months with an internal fixation device involving two plates set in orthogonal planes. Radiological and histological examinations were performed on harvested metatarsal bones. Three months after surgery Group #1 animals showed obvious signs of bone healing without achieving complete union in all cases. Evidence of a healing process was not observed in Group #2 animals, and histological examination confirmed the complete failure of bone repair in the 20 mm gaps. These results are comparable to those of other authors who have concluded that a bone gap corresponding to 1.4 times the diaphyseal diameter overshoots physiological bone healing capacities. This long bone defect model showed good biological properties allowing callus settlement with minimal impairment in Group #1 and permitted weightbearing and unrestricted motion in the animals. Such a sheep model would be useful for testing hard tissue biomaterials, bone healing enhancement or further developed as an experimental nonunion model.Metatarsal diaphyseal defects (length: 10 or 20 mm) maintained with plates were performed in sheep in search of nonunion after a three-month period. Radiological and histological examinations showed that 10 mm gaps healed spontaneously while 20 mm gaps did not. These results are comparable to those of other authors who concluded that a diaphyseal defect whose length exceeds 1.4 times its diameter is unable to repair. The good biological properties exhibited by this defect model seem to be convenient for testing bone substitutes or bone healing enhancement techniques.

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Evaluation of the bone healing process in an experimental tibial bone defect model in ovariectomized rats

Aging Clinical and Experimental Research ◽

10.1007/s40520-014-0199-x ◽

2014 ◽

Vol 26 (5) ◽

pp. 473-481 ◽

Cited By ~ 8

Author(s):

Hueliton Wilian Kido ◽

Paulo Sérgio Bossini ◽

Carla Roberta Tim ◽

Nivaldo Antônio Parizotto ◽

Anderson Ferreira da Cunha ◽

...

Keyword(s):

Bone Defect ◽

Bone Healing ◽

Healing Process ◽

Ovariectomized Rats ◽

Defect Model ◽

Tibial Bone ◽

Bone Healing Process

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Biomechanical assessment of freeze-dried allograft cortical bone plate graft in canine bone defect model

Veterinární Medicína ◽

10.17221/3029-vetmed ◽

2009 ◽

Vol 54 (No. 4) ◽

pp. 183-190 ◽

Cited By ~ 2

Author(s):

S.Y. Heo ◽

H.B. Lee ◽

K.C. Lee ◽

M.S. Kim ◽

C.S. Na ◽

...

Keyword(s):

Stainless Steel ◽

Cortical Bone ◽

Bone Defect ◽

Bone Screws ◽

Bone Plate ◽

Bending Test ◽

Application Site ◽

Defect Model ◽

Freeze Dried ◽

Significant Difference

Freeze-dried cortical bone can be used as a biological plate, either alone or in combination with other internal fixation devices, to stabilize fractures. In addition to it conferring mechanical stability, freeze-dried cortical bone may enhance fracture-healing and increase the bone stock. This study examined the effect of a freeze-dried allograft cortical bone plate (FACBP) on the biomechanical properties of an implant site in a canine bone defect model. Twelve adult mongrel dogs (around 4.8 kg) were used. A segmental critical-size defect (5 mm in length) at ulna diaphysis was created using an oscillating saw. The experimental animals were divided into two groups: eight dogs treated with an absorbable bone plate (FACBP) fixed by metal bone screws (Group A) and four dogs treated with a commercial stainless steel bone plate and metal bone screws (Group B). Bone healing was assessed by radiography, Dual-energy x-ray absorptiometry and a three-point bending test. The FACBP incorporated in the host bone produced complete remodeling of the cortical bone. There was no significant difference in the bone mineral density and biomechanical tests between the FACBP application site and normal ulna or a stainless steel bone plate of the ulna. These results suggest that FACBP facilitates recovery from a bone fracture by assisting in the induction of new bone formation in a defected fracture.

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Formononetin, a methoxy isoflavone, enhances bone regeneration in a mouse model of cortical bone defect

British Journal Of Nutrition ◽

10.1017/s0007114517001556 ◽

2017 ◽

Vol 117 (11) ◽

pp. 1511-1522 ◽

Cited By ~ 10

Author(s):

Krishna Bhan Singh ◽

Manisha Dixit ◽

Kapil Dev ◽

Rakesh Maurya ◽

Divya Singh

Keyword(s):

Bone Regeneration ◽

Cortical Bone ◽

Bone Defect ◽

Bone Healing ◽

Drill Hole ◽

Repair Process ◽

Fracture Repair ◽

Injury Site ◽

Healing Effect ◽

Ct Analysis

AbstractThe bone regeneration and healing effect of formononetin was evaluated in a cortical bone defect model that predominantly heals by intramembranous ossification. For this study, female Balb/c mice were ovariectomised (OVx) and a drill-hole injury was generated in the midfemoral bones of all animals. Treatment with formononetin commenced the day after and continued for 21 d. Parathyroid hormone (PTH1–34) was used as a reference standard. Animals were killed at days 10 and 21. Femur bones were collected at the injury site for histomorphometry studies using microcomputed tomography (μCT) and confocal microscopy. RNA and protein were harvested from the region surrounding the drill-hole injury. For immunohistochemistry, 5 µm sections of decalcified femur bone adjoining the drill-hole site were cut.μCT analysis showed that formononetin promoted bone healing at days 10 and 21 and the healing effect observed was significantly better than in Ovx mice and equal to PTH treatment in many aspects. Formononetin also significantly enhanced bone regeneration as assessed by calcein-labelling studies. In addition, formononetin enhanced the expression of osteogenic markers at the injury site in a manner similar to PTH. Formononetin treatment also led to predominant runt-related transcription factor 2 and osteocalcin localisation at the injury site. These results support the potential of formononetin to be a bone-healing agent and are suggestive of its promising role in the fracture-repair process.

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