Continuous PGE2 leads to net bone loss while intermittent PGE2 leads to net bone gain in lumbar vertebral bodies of adult female rats

Tian, Xia; Zhang, Q.; Zhao, Ronglan; Setterberg, R. B.; Zeng, Qing; Iturria, Stephen J.; Ma, Yang; Jee, Webster S. S.

doi:10.1016/j.bone.2007.12.228

Cited by 46 publications

(41 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…7, it seems that the area of red-appearing osteoids 24) reduced with increasing time after surgery. However, stimulated new bone formation areas were observed around newly formed bone 25) . Thus, we consider that new bone forms continuously until the defect has been completely replaced with newly formed bone.…”

Section: Histological Evaluationmentioning

confidence: 99%

Osteogenic Evaluation of DNA/Protamine Complex Paste in Rat Cranial Defects

Shinozaki

Yanagi

Yamaguchi

et al. 2013

J. Hard Tissue Biology.

View full text Add to dashboard Cite

A DNA/protamine complex powder, prepared from the reaction between DNA and protamine sulfate solutions, was mixed with water to make a paste. The ALP activity of MC 3T3 E1 cultured on a thin film of the complex paste was higher than that cultured on a plastic well. It was found that DNA/protamine complex induced new bone formation from the results of micro-computed tomography ( -CT) images and conventional histological sections with hematoxylin and eosin staining in rat cranial defect tests. -CT image analyses showed that newly formed bone areas in defects for DNA/protamine complex were significantly higher than those for sham operation (controls) two and three months after surgery. Although the area of red-appearing osteoids reduced with increasing times after surgery, stimulated new bone formation areas were observed around newly formed bone in histological sections stained with Villanuva osteochrome bone stain. Therefore, DNA/protamine complex paste with a biodegradable property will be a useful injectable biomaterial for the repair of bone defects.

show abstract

Section: Histological Evaluationmentioning

confidence: 99%

Osteogenic Evaluation of DNA/Protamine Complex Paste in Rat Cranial Defects

Shinozaki

Yanagi

Yamaguchi

et al. 2013

J. Hard Tissue Biology.

View full text Add to dashboard Cite

show abstract

“…A fascinating aspect of the mechanism of action of PTH and PGE2 is the fact that while they both induce a potent anabolic effect on bone when dosed intermittently (eg, daily) (140-141), they become catabolic when administered by continuous slow release (142)(143)(144). At present, there is no clear experimental explanation for this time-dependent action.…”

Section: Physiological and Pharmacological Regulators Of Bone Perfusionmentioning

confidence: 99%

The Key Role of the Blood Supply to Bone

2013

View full text Add to dashboard Cite

The importance of the vascular supply for bone is well-known to orthopaedists but is still rather overlooked within the wider field of skeletal research. Blood supplies oxygen, nutrients and regulatory factors to tissues, as well as removing metabolic waste products such as carbon dioxide and acid. Bone receives up to about 10% of cardiac output, and this blood supply permits a much higher degree of cellularity, remodelling and repair than is possible in cartilage, which is avascular. The blood supply to bone is delivered to the endosteal cavity by nutrient arteries, then flows through marrow sinusoids before exiting via numerous small vessels that ramify through the cortex. The marrow cavity affords a range of vascular niches that are thought to regulate the growth and differentiation of hematopoietic and stromal cells, in part via gradients of oxygen tension. The quality of vascular supply to bone tends to decline with age and may be compromised in common pathological settings, including diabetes, anaemias, chronic airway diseases and immobility, as well as by tumours. Reductions in vascular supply are associated with bone loss. This may be due in part to the direct effects of hypoxia, which blocks osteoblast function and bone formation but causes reciprocal increases in osteoclastogenesis and bone resorption. Common regulatory factors such as parathyroid hormone or nitrates, both of which are potent vasodilators, might exert their osteogenic effects on bone via the vasculature. These observations suggest that the bone vasculature will be a fruitful area for future research.

show abstract

“…Recently, in vivo animal studies examining the effects of varying doses, schedules and routes of administration of PGE 2 on bone have been reported. For example, Tian et al [60] showed that continuous PGE 2 infusion to rats led to bone loss by stimulating bone resorption to a higher degree than formation and shortening the formation period. In contrast, intermittent PGE 2 administration resulted in bone gain due to stimulated bone formation and shortened resorption periods [60].…”

Section: Figurementioning

confidence: 99%

“…For example, Tian et al [60] showed that continuous PGE 2 infusion to rats led to bone loss by stimulating bone resorption to a higher degree than formation and shortening the formation period. In contrast, intermittent PGE 2 administration resulted in bone gain due to stimulated bone formation and shortened resorption periods [60]. These results were confirmed in male C57BL/6 mice, where decreased trabecular bone volume was reported after 14 days treatment with a high dose of PGE 2 (6 mg/kg/day), suggesting increased bone resorption.…”

Section: Figurementioning

confidence: 99%