Bone tissue: Rebuilding and inflammation

2014 ◽  
Vol 155 (40) ◽  
pp. 1575-1583 ◽  
Author(s):  
Lajos Jakab
Keyword(s):  
Complex System ◽  
Bone Mass ◽  
Bone Metabolism ◽  
Bone Tissue ◽  
Inflammatory Process ◽  
Transforming Growth Factor ◽  
Structural Elements ◽  
Immune Functions ◽  
Exact Role ◽  
Α2 Macroglobulin

In this review the author summarizes the knowledge related to structural elements of bone tissue. The process of bone reorganisation and knowledge about the special feature of bone metabolism in human are also discussed. It is noted that due to the reorganisation, there is a complete renewal of bone tissue in every 10 years, and this renewal lasts throughout the life. However, there are life periods when osteoclast activity is low, e.g. in childhood and the second decade of life when the gain of bone mass may be as much as 40% of the final bone mass. Overactivity of osteoclasts occurs at age 60 years in men and somewhat earlier in women. Reorganization of bone tissue is an elementary requirement for the physiological functions (locomotion, hemopoiesis, immune functions). The RANK-RANKL-osteoprotegerin axis plays an important role in the regulation of bone metabolism. Bone mass is dependent on osteocytes; osteoblasts are building up while osteoclasts are reabsorbing bone tissue. In this process transcription factors, hormone-like substances and a large number of cytokines are involved. In addition, the inflammatory process within the bone tissue as well as the defending, reparative inflammation and specific immune response are of great importance in bone reorganisation. This is particularly valid for α2-macroglobulin and transforming growth factor, although the exact role in bone reorganization has not been fully explored. It can be concluded that the elements, which participate in bone reorganization and in defending inflammatory and specific immunological processes, are essentially identical. Therefore, the existence of an osteo-immunological complex system has been emerged. Orv. Hetil., 2014, 155(40), 1575–1583.

The benefits of a high-intensity aquatic exercise program (HydrOS) for bone metabolism and bone mass of postmenopausal women

2013 ◽  
Author(s):  
Linda Denise Fernandes Moreira ◽  
Fernanda Cerveira A. O. Fronza ◽  
Rodrigo Nolasco dos Santos ◽  
Patrícia Lins Zach ◽  
Ilda S. Kunii ◽  
...  
Keyword(s):  
Bone Mass ◽  
Bone Metabolism ◽  
Postmenopausal Women ◽  
High Intensity ◽  
Exercise Program ◽  
Aquatic Exercise

scholarly journals Bone and Mineral Metabolism Phenotypes in MEN1-Related and Sporadic Primary Hyperparathyroidism, before and after Parathyroidectomy

Cells ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1895
Author(s):  
Francesca Marini ◽  
Francesca Giusti ◽  
Federica Cioppi ◽  
Davide Maraghelli ◽  
Tiziana Cavalli ◽  
...  
Keyword(s):  
Primary Hyperparathyroidism ◽  
Bone Mass ◽  
Bone Metabolism ◽  
Mineral Metabolism ◽  
Parathyroid Tissue ◽  
Young Patients ◽  
Surgical Removal ◽  
Mineral Density ◽  
Bone Mass Loss ◽  
Before And After

Primary hyperparathyroidism (PHPT) is the most common endocrinopathy in multiple endocrine neoplasia type 1 (MEN1). Persistent levels of increased parathyroid hormone (PTH) result in a higher incidence of osteopenia and osteoporosis compared to the general population. Surgical removal of hyper-functioning parathyroid tissue is the therapy of choice. This retrospective study evaluated the effect of parathyroidectomy (PTX) on bone metabolism and bone mass in two series of patients with MEN1 PHPT and sporadic PHPT (sPHPT) by comparing bone metabolism-related biochemical markers and bone mineral density (BMD) before and after surgery. Our data confirmed, in a higher number of cases than in previously published studies, the efficacy of PTX, not only to rapidly restore normal levels of PTH and calcium, but also to normalize biochemical parameters of bone resorption and bone formation, and to improve spine and femur bone mass, in both MEN1 PHPT and sPHPT. Evaluation of single-patient BMD changes after surgery indicates an individual variable bone mass improvement in a great majority of MEN1 PHPT patients. In MEN1 patients, PTX is strongly suggested in the presence of increased PTH and hypercalcemia to prevent/reduce the early-onset bone mass loss and grant, in young patients, the achievement of the bone mass peak; routine monitoring of bone metabolism and bone mass should start from adolescence. Therapy with anti-fracture drugs is indicated in MEN1 patients with BMD lower than the age-matched normal values.

scholarly journals GDF11 promotes osteogenesis as opposed to MSTN, and follistatin, a MSTN/GDF11 inhibitor, increases muscle mass but weakens bone

2020 ◽  
Vol 117 (9) ◽  
pp. 4910-4920 ◽  
Author(s):  
Joonho Suh ◽  
Na-Kyung Kim ◽  
Seung-Hoon Lee ◽  
Je-Hyun Eom ◽  
Youngkyun Lee ◽  
...  
Keyword(s):  
Bone Mass ◽  
Muscle Mass ◽  
Transforming Growth Factor ◽  
Bone Fractures ◽  
Muscle Growth ◽  
Transforming Growth Factor Β ◽  
Biochemical Properties ◽  
Bmp Signaling ◽  
Morphogenetic Protein ◽  
Perinatal Lethality

Growth and differentiation factor 11 (GDF11) and myostatin (MSTN) are closely related transforming growth factor β (TGF-β) family members, but their biological functions are quite distinct. While MSTN has been widely shown to inhibit muscle growth, GDF11 regulates skeletal patterning and organ development during embryogenesis. Postnatal functions of GDF11, however, remain less clear and controversial. Due to the perinatal lethality ofGdf11null mice, previous studies used recombinant GDF11 protein to prove its postnatal function. However, recombinant GDF11 and MSTN proteins share nearly identical biochemical properties, and most GDF11-binding molecules have also been shown to bind MSTN, generating the possibility that the effects mediated by recombinant GDF11 protein actually reproduce the endogenous functions of MSTN. To clarify the endogenous functions of GDF11, here, we focus on genetic studies and show thatGdf11null mice, despite significantly down-regulatingMstnexpression, exhibit reduced bone mass through impaired osteoblast (OB) and chondrocyte (CH) maturations and increased osteoclastogenesis, while the opposite is observed inMstnnull mice that display enhanced bone mass. Mechanistically,Mstndeletion up-regulatesGdf11expression, which activates bone morphogenetic protein (BMP) signaling pathway to enhance osteogenesis. Also, mice overexpressing follistatin (FST), a MSTN/GDF11 inhibitor, exhibit increased muscle mass accompanied by bone fractures, unlikeMstnnull mice that display increased muscle mass without fractures, indicating that inhibition of GDF11 impairs bone strength. Together, our findings suggest that GDF11 promotes osteogenesis in contrast to MSTN, and these opposing roles of GDF11 and MSTN must be considered to avoid the detrimental effect of GDF11 inhibition when developing MSTN/GDF11 inhibitors for therapeutic purposes.

The Role of microRNAs in Osteoporosis Diagnostics

2021 ◽  
Vol 30 (03) ◽  
pp. 222-229
Author(s):  
Matthias Hackl ◽  
Elisabeth Semmelrock ◽  
Johannes Grillari
Keyword(s):  
Bone Mass ◽  
Bone Metabolism ◽  
Messenger Rna ◽  
Biological Fluids ◽  
Clinical Diagnostics ◽  
Bone Architecture ◽  
Estrogen Metabolism ◽  
Age Related

AbstractMicroRNAs (miRNAs) are short (18–24 nucleotides) non-coding RNA sequences that regulate gene expression via binding of messenger RNA. It is estimated that miRNAs co-regulate the expression of more than 70% of all human genes, many of which fulfil important roles in bone metabolism and muscle function. In-vitro and in-vivo experiments have shown that the targeted loss of miRNAs in distinct bone cell types (osteoblasts and osteoclasts) results in altered bone mass and bone architecture. These results emphasize the biological relevance of miRNAs for bone health.MiRNAs are not only considered as novel bone biomarkers because of their biological importance to bone metabolism, but also on the basis of other favorable properties: 1) Secretion of miRNAs from cells enables “minimally invasive” detection in biological fluids such as serum. 2) High stability of miRNAs in serum enables the retrospective analysis of frozen blood specimens. 3) Quantification of miRNAs in the serum is based on the RT-PCR - a robust method that is considered as the gold standard for the analysis of nucleic acids in clinical diagnostics.With regard to osteoporosis, it has been shown that many of the known risk factors are characterized by distinct miRNA profiles in the affected tissues: i) age-related loss of bone mass, ii) sarcopenia, iii) changes in estrogen metabolism and related changes Loss of bone mass, and iv) diabetes. Therefore, numerous studies in recent years have dealt with the characterization of miRNAs in the serum of osteoporosis patients and healthy controls, and were able to identify recurring miRNA patterns that are characteristic of osteoporosis. These novel biomarkers have great potential for the diagnosis and prognosis of osteoporosis and its clinical outcomes.The aim of this article is to give a summary of the current state of knowledge on the research and application of miRNA biomarkers in osteoporosis.

scholarly journals Recent insights into the implications of metabolism in plasmacytoid dendritic cell innate functions: Potential ways to control these functions

F1000Research ◽  
2017 ◽  
Vol 6 ◽  
pp. 456 ◽  
Author(s):  
Philippe Saas ◽  
Alexis Varin ◽  
Sylvain Perruche ◽  
Adam Ceroi
Keyword(s):  
Dendritic Cells ◽  
Lipid Metabolism ◽  
Nuclear Receptors ◽  
Immune Cells ◽  
Transforming Growth Factor ◽  
Plasmacytoid Dendritic Cell ◽  
Innate Immune ◽  
Type I ◽  
Innate Immune Cells ◽  
Immune Functions

There are more and more data concerning the role of cellular metabolism in innate immune cells, such as macrophages or conventional dendritic cells. However, few data are available currently concerning plasmacytoid dendritic cells (PDC), another type of innate immune cells. These cells are the main type I interferon (IFN) producing cells, but they also secrete other pro-inflammatory cytokines (e.g., tumor necrosis factor or interleukin [IL]-6) or immunomodulatory factors (e.g., IL-10 or transforming growth factor-β). Through these functions, PDC participate in antimicrobial responses or maintenance of immune tolerance, and have been implicated in the pathophysiology of several autoimmune diseases. Recent data support the idea that the glycolytic pathway (or glycolysis), as well as lipid metabolism (including both cholesterol and fatty acid metabolism) may impact some innate immune functions of PDC or may be involved in these functions after Toll-like receptor (TLR) 7/9 triggering. Some differences may be related to the origin of PDC (human versus mouse PDC or blood-sorted versus FLT3 ligand stimulated-bone marrow-sorted PDC). The kinetics of glycolysis may differ between human and murine PDC. In mouse PDC, metabolism changes promoted by TLR7/9 activation may depend on an autocrine/paracrine loop, implicating type I IFN and its receptor IFNAR, explaining a delayed glycolysis. Moreover, PDC functions can be modulated by the metabolism of cholesterol and fatty acids. This may occur via the production of lipid ligands that activate nuclear receptors (e.g., liver X receptor [LXR]) in PDC or through limiting intracellular cholesterol pool size (by statins or LXR agonists) in these cells. Finally, lipid-activated nuclear receptors (i.e., LXR or peroxisome proliferator activated receptor) may also directly interact with pro-inflammatory transcription factors, such as NF-κB. Here, we discuss how glycolysis and lipid metabolism may modulate PDC functions and how this may be harnessed in pathological situations where PDC play a detrimental role.

scholarly journals The influence of sports on indicators of mineral bone density among women descendants of migrants of KHMAO-Yugra

2016 ◽  
Vol 12 (1) ◽  
pp. 198-200
Author(s):  
Maxim V Stogov ◽  
Natalya V Chernitsyna ◽  
Roman V Kuchin
Keyword(s):  
Bone Density ◽  
Bone Mass ◽  
Bone Tissue ◽  
Preliminary Data ◽  
First Generation ◽  
Physical Culture ◽  
Mineral Density ◽  
Autonomous District ◽  
Middle Latitudes ◽  
Mineral Bone Density

The study shows that women descendants of migrants in the first generation, born and residing on the territory of KHMAO-Yugra, not engaged in physical culture and sports, according to densitometry mineral density of bone tissue shows signs of loss of bone mass, not observed in the residents of middle latitudes and the girls engaged in physical culture and sports, living in the Khanty-Mansiysk Autonomous district-Yugra. Preliminary data confirm the assumption that training in physical culture and sport contribute to the prevention of loss of bone mass in women living in the territory of KHMAO-Yugra.

scholarly journals A Review: Inflammatory Process in Alzheimer's Disease, Role of Cytokines

2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
Jose Miguel Rubio-Perez ◽  
Juana Maria Morillas-Ruiz
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Inflammatory Process ◽  
Transforming Growth Factor ◽  
Neurodegenerative Disorder ◽  
Epidemiological Studies ◽  
Brain Disorder ◽  
Amyloid A ◽  
Cytokines And Chemokines ◽  
Anti Inflammatory

Alzheimer's disease (AD) is the most common neurodegenerative disorder to date. Neuropathological hallmarks areβ-amyloid (Aβ) plaques and neurofibrillary tangles, but the inflammatory process has a fundamental role in the pathogenesis of AD. Inflammatory components related to AD neuroinflammation include brain cells such as microglia and astrocytes, the complement system, as well as cytokines and chemokines. Cytokines play a key role in inflammatory and anti-inflammatory processes in AD. An important factor in the onset of inflammatory process is the overexpression of interleukin (IL)-1, which produces many reactions in a vicious circle that cause dysfunction and neuronal death. Other important cytokines in neuroinflammation are IL-6 and tumor necrosis factor (TNF)-α. By contrast, other cytokines such as IL-1 receptor antagonist (IL-1ra), IL-4, IL-10, and transforming growth factor (TGF)-βcan suppress both proinflammatory cytokine production and their action, subsequently protecting the brain. It has been observed in epidemiological studies that treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) decreases the risk for developing AD. Unfortunately, clinical trials of NSAIDs in AD patients have not been very fruitful. Proinflammatory responses may be countered through polyphenols. Supplementation of these natural compounds may provide a new therapeutic line of approach to this brain disorder.

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