Bone Abstracts

Background: Marfan syndrome (MFS) is a rare connective tissue disorder caused by mutation in the gene encoding the extracellular matrix protein fibrillin-1 (FBN1), leading to transforming growth factor-beta (TGF-β) signaling dysregulation. Although decreased axial and peripheral bone mineral density (BMD) has been reported in adults with MFS, data about the evolution of bone mass during childhood and adolescence are limited.Objectives: The aim of th...

There is a growing body of evidence indicating the important role of the neonatal steroid milieu in programming sexually dimorphic pattern in various physiological systems. We tested the hypothesis that abnormal exposure to steroid hormones within a critical developmental period elicits permanent changes on tooth eruption, enamel mineralization, and leptin and corticosterone concentrations in adulthood. Newborn Wistar rats were divided into four groups, two male groups and two...

To evaluate the regeneration of alveolar bone after treatment with bone-resorption inhibitors in old acyclic rats that had been through a long period of low estrogen. Thirty-two female Wistar rats with 20 months old intact and ovariectomized (OVX at 4 months of age), were randomized into four groups (n=8/group): i) intact; ii) OVX/O (corn oil); iii) OVX/E2 (17β-estradiol, 400 μg) and iv) OVX/RLX (Raloxifene, 1 mg/kg per day). All treatments began ...

Histomorphometry is often adopted as a methodological approach in research of femoral bone structure. However, it is common do not describe technical details of procedure especially on the steps of macroscopy, paraffin embedding and microtomy. So we propose a simplified, reliable and reproducible method of histological processing for intertrochanteric region and femoral neck of mice, to ensure the achievement of tissue sections with similar structures, cell populations and his...

The Rickets is a disease which disturbs normal bone formation through different methods, like vitamin D deficiency, malabsorption, chronic renal disease, metaphisary dysplasia, low phosphorus and resistant rickets.The peak age at which rickets is most prevalent is usually 3–18 months, and the characteristic clinical features of this metabolic bone disease include enlargement of the epiphyses of the long bones and rib cage, bowing of the legs, bendin...

It is well known that thyroid hormone (TH) is essential for normal bone growth and development. However, the mechanisms by which TH regulates these processes are poorly understood. Recently, the sympathetic nervous system (SNS) was identified as a potent regulator of bone metabolism. In vivo studies by our group have shown that TH interacts with the SNS to regulate bone mass and structure, and that this interaction involves α2 adrenoceptor (α2-A...

Background: Long-term use of bisphosphonates has raised concerns about the association with Atypical Femur Fractures (AFFs) that have been reported mainly in postmenopausal women.Clinical case: An 18-year-old patient with juvenile osteoporosis based on X-linked osteoporosis due to a PLS3 mutation developed a low trauma femoral fracture after seven years of intravenous and two years of oral bisphosphonate use, fulfilling the revised ASBMR diagnostic crite...

Objectives: X-linked hypophosphataemia (XLH) is a rare, inherited, genetic disease characterised by renal phosphate wasting, bone mineralisation defects, rickets, abnormal tooth development, poor growth and, often, bone pain. Common treatment of children involves supplementation with oral phosphate and active vitamin D (often termed ‘conventional therapy’). The objective of this study was to identify and understand the perceived limitations of conventional therapy fo...

Objectives: Strong coordination between osteoblasts and bone marrow cells is fundamental for the regulation of healthy bone turnover and other (patho)physiological processes. Extracellular vesicles (EVs) mediate communication between cells via horizontal transfer of proteins and nucleic acids. Osteoblasts secrete EVs in the form of matrix vesicles involved in bone mineralization, however, information about a role in intercellular communication is still lacking. In this study, ...

The lactation has been considered a cause of bone loss in humans and animals. Studies have shown that during lactation, there is a significant reduction of bone mineral density. Rats at the end of lactation show reduced bone mass. The objective of this study was to verify the effect of lactation under osteogenic potential of bone marrow mesenchymal stem cells (BMMSCs) of female rats. Twelve Wistar rats were distributed among the control and lactating groups. The experiment was...