Effects of Phosphorus and Calcium to Phosphorus Consumption Ratio On Mineral Metabolism and Cardiometabolic Health

Phosphorus is a common additive used in food processing that is typically consumed in excess of the recommended daily allowance; however, our knowledge of its effects on health, in the context of normal renal function, is limited. Unlike phosphorus, calcium intake is generally less than recommended, and it has been hypothesized that the calcium to phosphorus ratio may be partly responsible for the proposed negative health consequences. Therefore, this study sought to determine the effects of increased phosphorus additive intake, in the context of high calcium consumption, on endocrine markers of mineral metabolism and cardiometabolic health. An outpatient feeding study was performed in which healthy adults were fed a run-in control diet for 2 weeks followed by a phosphorus additive enhanced diet with supplemental calcium to an approximate ratio of 1 (experimental diet) for 2 weeks. Blood and urine samples were collected, and participants had brachial flow-mediated dilatation measured, with analyses comparing follow-up measures to baseline. Two weeks of experimental diet increased serum fibroblast growth factor 23 concentrations but lowered body weight and serum leptin; however, other phosphorus responsive factors such as osteopontin and osteocalcin did not increase. A complementary study in male mice also demonstrated that the regulation of known dietary phosphorus responsive factors was mostly abrogated when dietary calcium was raised in parallel with phosphorus. In conclusion, the study identifies weight, leptin and insulin as responsive to dietary phosphorus and that certain aspects of the systemic phosphorus response are attenuated by a corresponding high calcium intake

Gene Therapy Strategies in Bone Tissue Engineering and Current Clinical Applications

Gene therapy provides a promising approach for regeneration and repair of injured bone. Application of gene therapy has displayed increased efficiency in various animal models and preclinical trials in comparison with traditional bone grafting methods. The objective of this review is to highlight fundamental principles of gene therapy strategies in bone tissue engineering and solutions of their current limitations for the healing of bone injury. Vector types are debated for the repair of defected site due to demonstration of constraints and applications of the protocols. In recent years, the combination of gene therapy strategies and bone tissue engineering has highly gained attention. We discussed viral and non-viral mediated delivery of therapeutic protein by using scaffolds for bone tissue engineering. Although pre-clinical studies have showed that gene therapy has very promising results to heal injured bone, there are several limitations regarding with the usage of gene delivery methods into clinical applications. Choice of suitable vector, selection of transgene and gene delivery protocols are the most outstanding questions. This article also addresses current state of gene delivery strategies in bone tissue engineering for their potential applications in clinical considerations

An Update On Bone Substitutes For Spinal Fusion

With the current advances in spinal surgery, an understanding of the precise biological mechanism of each bone substitute is necessary for inducing successful spinal fusion. In this review, the categories of bone substitutes include allografts, ceramics, demineralized bone matrix, osteoinductive factors, autogenous platelet concentrate, mesenchymal stem cells, and gene therapy. Further, clinical studies have been evaluated by their levels of evidence in order to elucidate the precise effect of the bone substitute employed and to establish clinical guidance. This article will review both clinical studies based on evidence and basic research in current advances in order to avoid as far as possible any chances of failure in the future and to understand cellular biology in novel technologies.Wo