acid-phosphatase and Abscess

Osteonecrosis of the jaws (ONJ) is a significant complication of antiresorptive medications, such as bisphosphonates and denosumab. Antiresorptive discontinuation to promote healing of ONJ lesions remains highly controversial and understudied. Here, we investigated whether antiresorptive discontinuation alters ONJ features in mice, employing the potent bisphosphonate zoledronic acid (ZA) or the receptor activator of NF-κB ligand (RANKL) inhibitor OPG-Fc, utilizing previously published ONJ animal models. Mice were treated with vehicle (veh), ZA, or OPG-Fc for 11 weeks to induce ONJ, and antiresorptives were discontinued for 6 or 10 weeks. Maxillae and mandibles were examined by μCT imaging and histologically. ONJ features in ZA and OPG-Fc groups included periosteal bone deposition, empty osteocyte lacunae, osteonecrotic areas, and bone exposure, each of which substantially resolved 10 weeks after discontinuing OPG-Fc but not ZA. Full recovery of tartrate-resistant acid phosphatase-positive (TRAP+) osteoclast numbers occurred after discontinuing OPG-Fc but not ZA. Our data provide the first experimental evidence demonstrating that discontinuation of a RANKL inhibitor, but not a bisphosphonate, reverses features of osteonecrosis in mice. It remains unclear whether antiresorptive discontinuation increases the risk of skeletal-related events in patients with bone metastases or fracture risk in osteoporosis patients, but these preclinical data may nonetheless help to inform discussions on the rationale for a "drug holiday" in managing the ONJ patient.

Topics: Abscess; Acid Phosphatase; Animals; Bisphosphonate-Associated Osteonecrosis of the Jaw; Bone Resorption; Denosumab; Diphosphonates; Disease Models, Animal; Imidazoles; Immunoglobulin Fc Fragments; Isoenzymes; Male; Mandible; Maxilla; Mice; Mice, Inbred C57BL; Osteoclasts; Osteoprotegerin; RANK Ligand; Rats; Recombinant Fusion Proteins; Tartrate-Resistant Acid Phosphatase; X-Ray Microtomography; Zoledronic Acid

The accumulation of ten metals in turpentine-induced abscesses of different ages has been studied in rats. The maximum metal concentration ratio between the abscesses and the non-inflamed contralateral muscle was greater than 1 for all the metals studied, the lowest being 2.5 for Zn, and the highest 36 for Th. The ratio remains greater than 1 for more than 28 days for all metals except Ga. There is a marked increase of beta-glucuronidase activity in the inflamed tissue which correlates well with the metal concentration. In contrast the acid phosphatase activity was reduced for the first few days after turpentine injection and never rose above the normal muscle activity. The metals showing the highest uptake in the inflamed lesion appear to be those which are transported in the blood as a transferrin complex.

Topics: Abscess; Acid Phosphatase; Animals; Glucuronidase; Male; Metals; Muscles; Radioisotopes; Rats

The activity of redox and hydrolytic enzymes was studied in the blood lymphocytes and neutrophils of rabbits infected with hemolitic Staphylococcus albus. The changes in the enzymatic activity of blood cells in generalized and localized forms of the inflammatory process depended on the form, course and duration of the disease. At early periods the indices of the acid phosphatase activity of lymphocytes had the greatest informative value for the diagnosis of the inflammatory process. The diagnostic significance of the activity of the alkaline phosphatase of neutrophils consisted in redistribution of cells by the degree of the enzyme activity.

Topics: Abscess; Acid Phosphatase; Alkaline Phosphatase; Animals; Clinical Enzyme Tests; Histocytochemistry; Lymphocytes; Neutrophils; Rabbits; Sepsis; Staphylococcal Infections; Succinate Dehydrogenase

Topics: Abscess; Acid Phosphatase; Agar; Animals; Cell Division; Cell Membrane; Cell Nucleus; Cell Wall; Coagulase; Cytoplasm; Histocytochemistry; Kidney Diseases; Mice; Microscopy, Electron; Microscopy, Electron, Scanning; Oxidation-Reduction; Protoplasts; Rodent Diseases; Staphylococcus; Succinate Dehydrogenase; Tellurium

Topics: Abscess; Acid Phosphatase; Aged; Alkaline Phosphatase; Eosinophilia; Esterases; Female; Humans; Male; Middle Aged; Oxidoreductases; Pelvic Neoplasms; Proctitis; Prospective Studies; Radiotherapy; Radiotherapy Dosage; Rectal Neoplasms; Rectum; Urinary Bladder Neoplasms; Uterine Cervical Neoplasms