Tartrate-resistant acid phosphatase

About: Tartrate-resistant acid phosphatase is a research topic. Over the lifetime, 1115 publications have been published within this topic receiving 45937 citations. The topic is also known as: HPAP & SPENCDI.

Anemarrhena asphodeloides Bunge ameliorates osteoporosis by suppressing osteoclastogenesis

Abstract: Anemarrhena asphodeloides Bunge has been traditionally used in Korean medicine for its antipyretic, diuretic, sedative, and antitussive effects. In the present study, the effects of an ethanol extract of A. asphodeloides Bunge (AAB) on osteoporosis and its underlying mechanisms on bone remodeling were investigated. Osteoporosis was induced in ICR strain mice by ovariectomy. The mice were divided into four groups: sham, ovariectomized, 17β‑estradiol and 100 mg/kg AAB. The treatment was continued for 4 weeks. Bone mineral density (BMD) and bone mineral content (BMC) were measured using dual‑energy X‑ray absorptiometry. In addition, Raw 264.7 cells were treated in the presence of 0.1, 1 and 10 µg/ml AAB with 100 ng/ml receptor activator of nuclear factor κΒ ligand (RANKL) to induce osteoclast formation and stained with tartrate resistant acid phosphatase. In addition, levels of osteoclast‑related factors were analyzed to investigate the signaling cascades in osteoclasts. The results demonstrated that AAB treatment reversed the decreases of both BMD and BMC in osteoporotic femurs. Additionally, the formation of osteoclasts was significantly suppressed by the AAB treatment in RANKL‑stimulated Raw 264.7 cells. Compared with cells treated with RANKL alone, the AAB‑treated osteoclasts had significantly decreased tumor necrosis factor‑α and interleukin‑6. The protein levels of c‑fos were also decreased in the AAB‑treated osteoclasts. Furthermore, the RANKL‑induced nuclear translocation of nuclear factor‑κB was attenuated in osteoclasts by the AAB treatment compared with cells treated with RANKL alone. Finally, AAB treatment downregulated the phosphorylation of mitogen‑activated protein kinases. The present results demonstrated that AAB exhibited ameliorative effects on osteoporosis by inhibiting osteoclastogenesis, and suggested that AAB may be a potential candidate for the treatment of osteoporosis.

Method of measuring bone resorption activity with a highly enriched population of prefusion osteoclast cells

Abstract: Methods of obtaining enriched populations of osteoclast precursor cells which can be released from tissue culture dishes and used for biochemical studies are described. Osteoblastic cells and bone marrow cells are co-cultured. Next a αv β3 receptor ligand, such as echistatin is used for cell detachment. The result is a 75-95% pure enriched population of tartrate resistant acid phosphatase (TRAP+) cells, in high yields (2-3×106 cells per experiment) can be obtained. These cells are mosty mononucleated and based on their characteristics are considered to be pre-fusion osteoclasts (pOC cells). The precursor osteoclasts can be reseeded onto osteoblasts to obtain an enriched population of mature, multinucleated osteoclast cells.

A Comparison of the Antiosteoporotic Effects of Cornelian Cherry (Cornus mas L.) Extracts from Red and Yellow Fruits Containing Different Constituents of Polyphenols and Iridoids in Osteoblasts and Osteoclasts

Abstract: Methods Polyphenolic and iridoid constituents of extracts were analyzed qualitatively and quantitatively using the ultraperformance liquid chromatography system coupled with a quadrupole-time of flight mass spectrometry. Primary cultured osteoblasts isolated from mouse calvarias and osteoclast-lineage primary cultured monocytes isolated from mouse bone marrow were used for the assessment of osteoblast and osteoclast differentiation. In the osteoblast culture, cellular viability, alkaline phosphatase (ALP) activity, ALP staining, and mRNA expression of Alpl and Runx2 were examined. In the osteoclast culture, the examined parameters were cellular viability, tartrate-resistant acid phosphatase (TRAP) activity and staining, and mRNA expression of Nfatc1, Ctsk, and Acp. Results A total of 41 main compounds of iridoids, anthocyanins, hydrolysable tannins, phenolic acids, and flavonols were identified in the three extracts. RED EXT1 contained most of the tested polyphenols and iridoids and was the only extract containing anthocyanins. YL EXT2 contained only one iridoid, loganic acid and gallic acid. YL EXT3 comprised a mixture of iridoids and polyphenols. RED EXT1, YL EXT 2, and to a lesser extent YL EXT3 promoted osteoblast differentiation increasing significantly ALP activity and the amount of ALP-positive stained cells. All extracts upregulated mRNA expression of Alpl and Runx2. RED EXT1 caused the most significant decrease in TRAP activity and the numbers of TRAP-positive multinucleated cells. RED EXT1 caused also the most significant downregulation of mRNA expression of osteoclast related genes Nfatc1, Ctsk, and Acp5. Extracts from yellow fruits, mostly YL EXT2 caused lower, but still significant inhibitory effect on TRAP and osteoclast related genes. Conclusions The main conclusion of our study is that all three extracts, especially RED EXT1 from red cornelian cherry fruits, possess the antiosteoporotic potential and may be a promising phytomedicine candidate for the prevention and treatment of osteoporosis.

Colorimetric and fluorescent TRAP assays for visualising and quantifying fish osteoclast activity

Abstract: Histochemical detection of tartrate-resistant acid phosphatase (TRAP) activity is a fundamental technique for visualizing osteoclastic bone resorption and assessing osteoclast activity status in tissues. This approach has mostly employed colorimetric detection, which has limited quantification of activity in situ and co-labelling with other skeletal markers. Here we report simple colorimetric and fluorescent TRAP assays in zebrafish and medaka, two important model organisms for investigating the pathogenesis of bone disorders. We show fluorescent TRAP staining, utilising the ELF97 substrate, is a rapid, robust and stable system to visualise and quantify osteoclast activity in zebrafish, and is compatible with other fluorescence stains, transgenic lines and antibody approaches. Using this approach, we show that TRAP activity is predominantly found around the base of the zebrafish pharyngeal teeth, where osteoclast activity state appears to be heterogeneous.

Bone morphogenetic protein 2 controls steroid-induced osteonecrosis of the femoral head via directly inhibiting interleukin-34 expression

Abstract: Increased inflammatory response is one of the major characteristics of osteonecrosis of the femoral head (ONFH). We aimed to investigate the function of bone morphogenetic protein 2 (BMP-2)/interleukin (IL)-34 axis in the inflammatory responses of ONFH. The systemic and local expression of BMPs in ONFH patients was detected by qRT-PCR and ELISA. In vitro osteoclast differentiation and ONFH mouse models, induced by 20 mg/kg methylprednisolone through i.m. injection, were established using WT and BMP-2-/- mice to explore the regulatory role of BMP-2 in pro-inflammatory responses and bone defects of ONFH. IL-34 expression and function were examined in vitro and in vivo through qRT-PCR, tartrate-resistant acid phosphatase (TRAP) staining, and gene knockout. The systemic and local expression of BMPs was elevated in ONFH patients. BMP-2 reduced the production of pro-inflammatory cytokines and inhibited the differentiation of osteoclasts. Mechanistically, BMP-2 inhibited osteoclasts formation through suppressing IL-34 expression and then promoted bone repair and alleviated ONFH. In conclusion, our study reveals that BMP-2 inhibits inflammatory responses and osteoclast formation through downregulating IL-34.