The bone formation of periarticular connective tissue after head injury and total hip arthroplasty is included in the category of heterotopic ossification. Induction of a new bone formation in the soft tissue is related to various materials such as bone morphogenic protein. The alkaline phosphatase and acid phosphatase act as important factors in the formation and absorption of the bone. The acid phospatase has the important function of acting as the control with specific activity of phosphatase in vivo. Cholecalciferol induces absorption of the calcium in the alimentary tract and bone resorption and increment of bone calcification, whereas disodium etidronate inhibits the deposition and dissolution of calcium salt and formation of heterotopic bone. This paper reports on the relationship of alkaline phosphatase and various phosphoaminoacid phosphatase which affect the cellular differentiation and remodelling in the heterotopic ossification, with the effect of cholecalciferol and disodium etidronate on the heterotopic bone induction in rats. The following results were obtained: 1. The contents of the calcium in the implanted bone matrix increased markedly from two to five weeks. There was no changes in the calcium content by cholecalciferol or in the administration of small doses of disodium etidronate (5mg/kg). However, in the administration of large dose of disodium etidronate (25mg/kg), calcium mobilization was totally suppressed for the whole period of the experiment. 2. The protein content in the implanted bone matrix did not much change for the whole period of the experiment and the administratinn of cholecalciferol or disodium etidronate also had no effect on the protein content. 3. The activities of alkaline phosphatase in the implanted bone matrix peaked at two weeks in control or cholecalciferol group, whereas disodium etidronate admninstration caused the highest activity in the third week. 4. The activity of acid phosphatase in the implanted bone matrix increased in first and third weeks by cholecalciferol treatment. Disoidum etidronate inhibited the activity of the acid phosphatase in the first, fourth & sixth weeks of implantation. 5. The activity of phosphoserine phosphatase increased due to cholecalciferol treatment, but was significantly inhibited by disodium etidronate (25mg/kg) treatment. 6. The activity of phosphothreonine phosphatase in the implanted bone matrix slightly increased due to cholecalciferol treatment, whereas the activity decreased significantly for the whole period of the experiment by disodium etidronate (25mg/kg) treatment. 7. The activity of phosphotyrosine phosphatase in the implanted bone matrix was not change much for the whole period of the experiment and the administration of cholecalciferol or disodium etidronate had no effect on the activity of phosphotyrosine phosphatase. In conclusion, the disodium etidronate (25mg/kg) almost completely inhibited the molilization of calcium and the activities of acid phosphatase, phosphoserine and phosphothreonine phosphatases. Therefore, it can be suggested that the above phosphatases are closely related to the action mechanism of disodium etidronate.
Absorption ; Acid Phosphatase ; Alkaline Phosphatase ; Animals ; Arthroplasty, Replacement, Hip ; Bone Matrix ; Bone Resorption ; Calcium ; Cholecalciferol ; Connective Tissue ; Craniocerebral Trauma ; Etidronic Acid ; Ossification, Heterotopic ; Osteogenesis ; Phosphoric Monoester Hydrolases ; Phosphoserine ; Phosphothreonine ; Protein Tyrosine Phosphatases ; Rats

Recent evidence supports a neuroprotective role of Src homology 2-containing protein tyrosine phosphatase 2 (SHP-2) against ischemic brain injury. However, the molecular mechanisms of SHP-2 activation and those governing how SHP-2 exerts its function under oxidative stress conditions are not well understood. Recently we have reported that reactive oxygen species (ROS)-mediated oxidative stress promotes the phosphorylation of endogenous SHP-2 through lipid rafts, and that this phosphorylation strongly occurs in astrocytes, but not in microglia. To investigate the molecules involved in events leading to phosphorylation of SHP-2, raft proteins were analyzed using astrocytes and microglia. Interestingly, caveolin-1 and -2 were detected only in astrocytes but not in microglia, whereas flotillin-1 was expressed in both cell types. To examine whether the H2O2-dependent phosphorylation of SHP-2 is mediated by caveolin-1, we used specific small interfering RNA (siRNA) to downregulate caveolin-1 expression. In the presence of caveolin-1 siRNA, the level of SHP-2 phosphorylation induced by H2O2 was significantly decreased, compared with in the presence of control siRNA. Overexpression of caveolin-1 effectively increased H2O2-induced SHP-2 phosphorylation in microglia. Lastly, H2O2 induced extracellular signal-regulated kinase (ERK) activation in astrocytes through caveolin-1. Our results suggest that caveolin-1 is involved in astrocyte-specific intracellular responses linked to the SHP-2-mediated signaling cascade following ROS-induced oxidative stress.
Animals ; Astrocytes/*metabolism ; Caveolin 1/*genetics/metabolism ; Caveolin 2/genetics ; Cell Line ; Cells, Cultured ; Extracellular Signal-Regulated MAP Kinases/metabolism ; Gene Expression ; Humans ; Microglia/metabolism ; Phosphoric Monoester Hydrolases/*metabolism ; Phosphorylation ; Protein Tyrosine Phosphatase, Non-Receptor Type 11/*metabolism ; Rats ; Reactive Oxygen Species/*metabolism

The purpose of this study was to observe the effects of pregnancy on the experimental tooth movement and alveolar bone turnover process of Sprague-Dawley female rat. Sixty rats were divided into pregnant-tooth movement group(P-Tm), normal-tooth movement group(N-Tm) and normal group(N). Maxillary first molar appliances were inserted bilaterally and activated to 40grams. To measure the amount of tooth movement, x-ray was taken 2 times after appliance insertion and before sacrifice. Animals were sacrificed at 1,3,7,14 days(N=5). Just after sacrifice, alveolar bones were collected and frozen immediately for biochemical analysis. Tooth movement was assessed cepha~,ometrically and tartrate-resistant acid(TRAP) and alkaline phosphatase (ALP) activities were measured in extracts of paradental alveolar bone. The results were as follows: 1. The amount of tooth movement in P-Tm group was greater than that of N-Tm group(p<0.01). 2. Alveolar bone ALP of normal tooth movement group was not significantly different from the control, TRAP was significantly different from the control(p<0.01). In normal tooth movement group, alveolar bone ALP was increased gradually and peak(day 7) fell off significantly at day 14(p<0.05). The peak of alveolar bone TRAP(day 7) fell off slightly, sustained day 14(p<0.01). 3. Alveolar bone ALP and TRAP of pregnant tooth movement group were not significantly different from that of normal tooth movement group. In pregnant tooth movement group, alveolar bone ALP was increased at day 3(p<0.01) and fell off significantly at day 7-14, alveolar bone TRAP were increased at day 3 and sustained day 14. 4. The peak of alveolar bone phosphatases in pregnant tooth movement group(day3) preceded the peak in normal tooth movement group(day7)(p<0.01). According to the above results, we suggested that bone resorption activity was increased in alveolar bone of pregnant rat, and the degree of tooth movement in pregnancy may be greater than that of normal group because of high bone turnover of alveolar bone in pregnant rat.
Alkaline Phosphatase ; Animals ; Bone Resorption ; Female ; Humans ; Molar ; Phosphoric Monoester Hydrolases ; Pregnancy* ; Rats* ; Rats, Sprague-Dawley ; Tooth Movement* ; Tooth*

OBJECTIVE: The BCL2 family proteins are critical mediators of cellular apoptosis and, as such, have been implicated as determinants of cancer cell chemo-sensitivity. Recently, it has been demonstrated that the phosphorylation status of the BCL2 antagonist of cell death (BAD) protein may influence ovarian cancer (OVCA) cell sensitivity to cisplatin. Here, we sought to evaluate how kinase and phosphatase components of the BAD apoptosis pathway influence OVCA chemo-sensitivity. METHODS: Protein levels of cyclin-dependent kinase 1 (CDK1) and protein phosphatase 2C (PP2C) were measured by immunofluorescence in a series of 64 primary advanced-stage serous OVCA patient samples. In parallel, levels of cAMP-dependent protein kinase (PKA), AKT, and PP2C were quantified by Western blot analysis in paired mother/daughter platinum-sensitive/resistant OVCA cell lines (A2008/C13, A2780S/A2780CP, Chi/ChiR). BAD pathway kinase CDK1 was depleted using siRNA transfection, and the influence on BAD phosphorylation and cisplatin-induced apoptosis was evaluated. RESULTS: OVCA patient samples that demonstrated complete responses to primary platinum-based therapy demonstrated 4-fold higher CDK1 (p<0.0001) and 2-fold lower PP2C (p=0.14) protein levels than samples that demonstrated incomplete responses. Protein levels of PP2C were lower in the platinum-resistant versus that shown in the platinum-sensitive OVCA cell line sub-clones. Levels of PKA were higher in all platinum-resistant than in platinum-sensitive OVCA cell line sub-clones. Selective siRNA depletion of CDK1 increased sensitivity to cisplatin-induced apoptosis (p<0.002). CONCLUSION: BAD pathway kinases and phosphatases, including CDK1 and PP2C, are associated with OVCA sensitivity to platinum and may represent therapeutic opportunities to enhance cytotoxic efficacy.
Apoptosis ; Blotting, Western ; CDC2 Protein Kinase ; Cell Death ; Cell Line ; Cisplatin ; Cyclic AMP-Dependent Protein Kinases ; Fluorescent Antibody Technique ; Humans ; Ovarian Neoplasms ; Phosphoprotein Phosphatases ; Phosphoric Monoester Hydrolases ; Phosphorylation ; Phosphotransferases ; Platinum ; Proteins ; RNA, Small Interfering ; Transfection

The purpose of this study was to investigate the alveolar bone turnover in diabetic rat, and to compare the alveolar bone turnover during tooth movement in diabetes with that in normal control. Eighty Male Sprague-Dawley strain rats(8th week) were divided into normal control(N), normal-tooth movement (N-tm), diabetes(D), and diabetes-tooth movement(D-tm) groups. Eighteen days before the start of the experiment, diabetes was induced with a single injection of streptozotocin 50mg/kg of body weight in citrate buffer as vehicle via the tail vein. Maxillary first molars of rats were moved mesially by 40 grams of the closed coil spring. Experimental animals were sacrificed after 1d, 3d, 7d, and 14d experimental period, and the alveolar bone around the maxillary first molars were assayed biochemically for acid phsophatase(ACP) and tartrate-resistant acid phosphatase (TRAP) as bone resorption markers, and alkaline phosphatase(ALP) and osteocalcin(OC) as bone formation markers. TRAP and OC concentration in serum and alveolar bone of D group were lower than those in N group, and especially OC concentration decreased more following diabetes prolonged, which showed the decreased skeletal and alveolar bone resorption and formation potential in diabetic rats. In N-tm group compared with N group, alveolar bone ACP and TRAP concentrations were highest at 1d and 3d(p<0.01), decreased after then, and showed lowest at 14d, and alveolar bone OC concentration was higher at 3d, 7d, and 14d(p<0.001) and showed a tendency of peak level at 7d. which showed the peak of concentration of bone resorption markers at 1d-3d and those of bone formation markers at 7d. In D-tm group compared with N group, alveolar bone ACP and TRAP concentrations were higher at 3d, 7d and 14d(p<0.001), and tended to reach peak value at 7d and persisted through 14d, and alveolar bone ALP and OC concentration increased but not different from that of N group. The amount of tooth movement in D group were greater than that of N group at all experimental period. Those results were suggested that during diabetes, the alveolar and skeletal bone undergo low bone turnover and the more amount of tooth movement, but because the peak time of alveolar bone resorption activity was delayed and sustained in longer period of tooth movement and alveolar bone formation activity is lower than that of normal tooth movement, the periodontal space is supposed to be larger during tooth movement.
Acid Phosphatase ; Animals ; Body Weight ; Bone Resorption ; Citric Acid ; Humans ; Male ; Molar ; Osteocalcin ; Osteogenesis ; Phosphoric Monoester Hydrolases ; Rats* ; Rats, Sprague-Dawley ; Streptozocin ; Tooth Movement* ; Tooth* ; Veins

Mutation of leucine-rich repeat kinase 2 (LRRK2) causes an autosomal dominant and late-onset familial Parkinson's disease (PD). Recently, we reported that LRRK2 directly binds to and phosphorylates the threonine 474 (T474)-containing Thr-X-Arg(Lys) (TXR) motif of focal adhesion kinase (FAK), thereby inhibiting the phosphorylation of FAK at tyrosine (Y) 397 residue (pY397-FAK), which is a marker of its activation. Mechanistically, however, it remained unclear how T474-FAK phosphorylation suppressed FAK activation. Here, we report that T474-FAK phosphorylation could inhibit FAK activation via at least two different mechanisms. First, T474 phosphorylation appears to induce a conformational change of FAK, enabling its N-terminal FERM domain to autoinhibit Y397 phosphorylation. This is supported by the observation that the levels of pY397-FAK were increased by deletion of the FERM domain and/or mutation of the FERM domain to prevent its interaction with the kinase domain of FAK. Second, pT474-FAK appears to recruit SHP-2, which is a phosphatase responsible for dephosphorylating pY397-FAK. We found that mutation of T474 into glutamate (T474E-FAK) to mimic phosphorylation induced more strong interaction with SHP-2 than WT-FAK, and that pharmacological inhibition of SHP-2 with NSC-87877 rescued the level of pY397 in HEK293T cells. These results collectively show that LRRK2 suppresses FAK activation through diverse mechanisms that include the promotion of autoinhibition and/or the recruitment of phosphatases, such as SHP-2.
Focal Adhesion Protein-Tyrosine Kinases ; Glutamic Acid ; Parkinson Disease ; Phosphoric Monoester Hydrolases ; Phosphorylation ; Phosphotransferases ; Protein Tyrosine Phosphatase, Non-Receptor Type 11* ; Threonine ; Tyrosine*

OBJECTIVETo study the association of muscle-specific glycogen-targeting regulatory subunit of the glucogen-bound protein phosphatase 1 (PPP1R3) gene codon 905 Asp/Tyr polymorphism with type 2 diabetes in Chinese Han population in Hefei region of Anhui province.

METHODSPPP1R3 gene Asp905Tyr polymorphism was detected by polymerase chain reaction and appropriate restriction enzyme (PCR-RFLP) in 262 type 2 diabetic cases and 104 normal controls. Case and control groups were divided into subgroups by body mass index (BMI) 25 kg/m2.

RESULTSWhen PPP1R3 gene Asp905Tyr polymorphism was not associated with type 2 diabetes mellitus. When subjects with BMI < 25 kg/m2 and Tyr/Tyr genotypes were used as reference. Subjects with Asp905 and BMI > or = 25 kg/m2 had a 3.69-fold increase of risk suffering from type 2 diabetes (OR = 3.69, 95% CI: 1.38-8.89, P=0.006).

CONCLUSIONSPPP1R3 gene Asp905Tyr polymorphism did not seem to play a critical role in the development of type 2 diabetes mellitus in Han population of Chinese in Anhui province but interaction between the Asp905 and BMI cause the increase of risk of type 2 diabetes.

Adult ; Alleles ; Aspartic Acid ; genetics ; China ; epidemiology ; ethnology ; Diabetes Mellitus, Type 2 ; epidemiology ; etiology ; genetics ; Female ; Gene Frequency ; Genotype ; Humans ; Male ; Middle Aged ; Obesity ; complications ; Phosphoprotein Phosphatases ; genetics ; Polymerase Chain Reaction ; Polymorphism, Genetic ; Polymorphism, Restriction Fragment Length ; Protein Phosphatase 1 ; Risk Factors ; Tyrosine ; genetics

Phosphoprotein Phosphatases ; Kinetics ; Protein Phosphatase 2/metabolism*

STUDY DESIGN: Prospective clinical study. PURPOSE: We evaluated the challenges faced during diagnosis and management of patients with subacute pyogenic discitis and discussed various clues in clinical history, radiologic and hematologic parameters of these patients that helped in establishing their diagnosis. OVERVIEW OF LITERATURE: Present literature available shows that in patients with subacute spondylodiscitis and infection with less virulent organisms, the clinical picture often is confusing and the initial radiologic and hematologic studies do not contribute much toward establishing the diagnosis. METHODS: Demographic pattern, predisposing factors, clinical presentation, comorbidities, microbiology, treatment, neurologic recovery, and complications of 11 patients were prospectively reviewed regarding their contribution toward the conformation of diagnosis of subacute pyogenic discitis. RESULTS: Mean age at presentation was 46.0 years with average preoperative Oswestry Disability Index and Visual Analog Scale scores of 83.4 and 7.18, respectively. Mean follow-up duration was 12.0 months. The most common site of infection was the lumbar spine, followed by the thoracic spine (n=1). Infective organisms were isolated in only 45% of cases. Staphylococcus aureus was the most common causative organism isolated. CONCLUSIONS: Diagnosing subacute spondylodiscitis in a patient presenting with subacute low backache poses a diagnostic challenge. Clinical and radiologic picture are deceiving, and bacteriologic results often are negative, further complicating the picture. A detailed medical history along with clinical, radiologic, and biochemical parameters prevents missing the diagnosis. Serial serum C-reactive protein and alkaline phosphatases were more reliable blood parameters in cases of subacute presentation.
Alkaline Phosphatase ; C-Reactive Protein ; Causality ; Clinical Study ; Comorbidity ; Diagnosis ; Discitis ; Follow-Up Studies ; Humans ; Low Back Pain ; Lumbar Vertebrae ; Phosphoric Monoester Hydrolases ; Prospective Studies ; Spine ; Staphylococcal Infections ; Staphylococcus aureus ; Tertiary Care Centers ; Tertiary Healthcare ; Visual Analog Scale

The term 'inflammation' was first introduced by Celsus almost 2000 years ago. Biological and medical researchers have shown increasing interest in inflammation over the past few decades, in part due to the emerging burden of chronic and degenerative diseases resulting from the increased longevity that has arisen thanks to modern medicine. Inflammation is believed to play critical roles in the pathogenesis of degenerative brain diseases, including Alzheimer's disease and Parkinson's disease. Accordingly, researchers have sought to combat such diseases by controlling inflammatory responses. In this review, we describe the endogenous inflammatory stimulators and signaling pathways in the brain. In particular, our group has focused on the JAK-STAT pathway, identifying anti-inflammatory targets and testing the effects of various anti-inflammatory drugs. This work has shown that the JAK-STAT pathway and its downstream are negatively regulated by phosphatases (SHP2 and MKP-1), inhibitory proteins (SOCS1 and SOCS3) and a nuclear receptor (LXR). These negative regulators are controlled at various levels (e.g. transcriptional, post-transcriptional and post-translational). Future study of these proteins could facilitate the manipulation of the inflammatory response, which plays ubiquitous, diverse and ambivalent roles under physiological and pathological conditions.
Alzheimer Disease ; Brain ; Brain Diseases ; History, Modern 1601- ; Inflammation ; Longevity ; Neurons* ; Parkinson Disease ; Phosphoric Monoester Hydrolases