Dependent Acid Phosphatase Research Articles

Protective effect of bacterial melanin in the substantia nigra in a rat model of Parkinson's disease

The major cause of Parkinson's disease is progressive disturbance of dopaminergic neurons of the substantia nigra, as well as their nerve endings located in the striatum. Therefore, therapy aimed at slowing the death of dopaminergic neurons can be effective. In recent decades, various types of neuroprotective agents have been successfully used in the treatment of neurodegenerative diseases, after which the restoration of structural disfunctions of the CNS is accelerated. In the present study, we used bacterial melanin, the therapeutic effect of which is due to the improvement of the trophic effects of the brain tissue, inhibition of the inflammatory process and gliosis. The comparative study of morphological and functional state of the substantia nigra pars compacta in a rotenone model of Parkinson's disease and combined with introduction of bacterial melanin was carried out. For morphological and histochemical study, the method of detecting the activity of Ca2 + - dependent acid phosphatase was used. The analysis of the data obtained showed that during rotenone intoxication, neuronal death and substantia nigra depigmentation are observed, as well as sharp morphological changes in intracellular structures occur, which indicates gross metabolic and morphological disorders. With the introduction of bacterial melanin, there is a tendency to preserve the normal morphological picture of the neurons of the substantia nigra pars compacta, in comparison with the Parkinson's disease model. Thus, bacterial melanin acts as a neuroprotective agent and has a supportive role in Parkinson's disease. 
 Keywords: bacterial melanin, Parkinson's Disease, substantia nigra

Protective effect of taurine on cellular structures in rat hippocampus following ethanol intoxication.

Background. Distinct brain structures, in particular, the hippocampus, have a selective sensitivity to acute and chronic alcohol intoxication. Study of the pathogenesis of alcohol-related brain damage with a view to the development of methods of prevention and treatment is an urgent task.Objective.Our main interest was in elucidating the effects of the biologically active substance, such as taurine on cellular structures in the hippocampus following ethanol intoxication.Methods.We applied a histochemical method to estimate the Ca2 + -dependent acid phosphatase activity. The present study was carried out in female albino rats. All experimental animals received an ethanol (15%) diet as their sole source of fluid at various time points.To study the effect of taurine on cellular structures of the rat brain following short-term and chronic alcohol consumption, rats were given daily injections of taurine solution for 7 days. Results. The morphological picture of the hippocampus is characterized by swelling of granular cells in the dentate gyrus that undergo chromatolysis, as well as a decrease in numerical density and a weak expression of processes of pyramidal neurons in the early stages of alcohol consumption. Degenerative changes occur in pyramidal cells in the hippocampus in the middle periods of alcohol consumption. The density of neurons is decreased; pyramidal cells lose their characteristic shape. In the conditions of long-term alcohol consumption, not only changes in the size and number of pyramidal neurons but also in the volume of the hippocampus and its regions are observed. The morphological picture of hippocampal neurons is a morphological proof of the disorders of their metabolism. In rats treated with taurine, there are positive changes in the structural properties of neurons and an increase in phosphatase activity (increased metabolism) in the hippocampus, which determines cell survival and functional recovery of irritated neurons. Conclusion. The results indicate that taurine has a neuroprotective effect on cellular structures in rat hippocampus.

Protective effects of hydroponic Teucrium polium on hippocampal neurodegeneration in ovariectomized rats.

BackgroundThe hippocampus is a target of ovarian hormones, and is necessary for memory. Ovarian hormone loss is associated with a progressive reduction in synaptic strength and dendritic spine. Teucrium polium has beneficial effects on learning and memory. However, it remains unknown whether Teucrium polium ameliorates hippocampal cells spike activity and morphological impairments induced by estrogen deficiency.MethodsIn the present study, we investigated the effects of hydroponic Teucrium polium on hippocampal neuronal activity and morpho-histochemistry of bilateral ovariectomized (OVX) rats. Tetanic potentiation or depression with posttetanic potentiation and depression was recorded extracellularly in response to ipsilateral entorhinal cortex high frequency stimulation. In morpho-histochemical study revealing of the activity of Ca2+-dependent acid phosphatase was observed. In all groups (sham-operated, sham + Teucrium polium, OVX, OVX + Teucrium polium), most recorded hippocampal neurons at HFS of entorhinal cortex showed TD-PTP responses.ResultsAfter 8 weeks in OVX group an anomalous evoked spike activity was detected (a high percentage of typical areactive units). In OVX + Teucrium polium group a synaptic activity was revealed, indicating prevention OVX-induced degenerative alterations: balance of types of responses was close to norm and areactive units were not recorded. All recorded neurons in sham + Teucrium polium group were characterized by the highest mean frequency background and poststimulus activity. In OVX+ Teucrium polium group the hippocampal cells had recovered their size and shape in CA1 and CA3 field compared with OVX group where hippocampal cells were characterized by a sharp drop in phosphatase activity and there was a complete lack of processes reaction.ConclusionThus, Teucrium polium reduced OVX-induce neurodegenerative alterations in entorhinal cortex-hippocamp circuitry and facilitated neuronal survival by modulating activity of neurotransmitters and network plasticity.

Detection of Ca2+-dependent acid phosphatase activity identifies neuronal integrity in damaged rat central nervous system after application of bacterial melanin

The study aims to confirm the neuroregenerative effects of bacterial melanin (BM) on central nervous system injury using a special staining method based on the detection of Ca2+-dependent acid phosphatase activity. Twenty-four rats were randomly assigned to undergo either unilateral destruction of sensorimotor cortex (group I; n = 12) or unilateral rubrospinal tract transection at the cervical level (C3–4) (group II; n = 12). In each group, six rats were randomly selected after surgery to undergo intramuscular injection of BM solution (BM subgroup) and the remaining six rats were intramuscularly injected with saline (saline subgroup). Neurological testing confirmed that BM accelerated the recovery of motor function in rats from both BM and saline subgroups. Two months after surgery, Ca2+-dependent acid phosphatase activity detection in combination with Chilingarian’s calcium adenoside triphosphate method revealed that BM stimulated the sprouting of fibers and dilated the capillaries in the brain and spinal cord. These results suggest that BM can promote the recovery of motor function of rats with central nervous system injury; and detection of Ca2+-dependent acid phosphatase activity is a fast and easy method used to study the regeneration-promoting effects of BM on the injured central nervous system.

Three indel variants in chicken LPIN1 exon 6/flanking region are associated with performance and carcass traits

LPIN1 is a Mg2+-dependent phosphatidic acid phosphatase. Variation in chicken LPIN1 exon 6 and its flanking regions were identified and three indel variants in 6 breeds and their associations with performance traits were studied.Seven variants were detected from 6 breeds, which contained a synonymous tri-allelic variant (c.924A/T/C) and three indels. The exon 6 variants detected from chicken breeds were conserved among bird species. The indel variation frequency presented clear differences among breeds.Two coding indels (c.1014-1018del3 and c.1125-1138del12) were multiples of three nucleotides and maintained the open reading frames of LPIN1 proteins. However, they were predicted to result in the clear change of the RNA secondary structure of chicken LPIN1 exon 6 and LPIN1 protein conformation.The association analysis showed that c.871–15-22del6 variation had a significant effect on body weight at hatch (BW0) and 2 weeks (BW2); c. 1014-1018del3 variation had a significant effect on BW4, BW6, caecum length and gizzard weight (GW) traits; c.1125-1138del12 variation had a significant effect on BW12, shank length at 4 weeks (SL4), carcass weight, lactate dehydrogenase traits (LDH), glucose (GLU) and albumin (ALB) traits. The genotype combination for c.1014-1018del3 and c.1125-1138del12 also presented significant effects on SL4, SL8, GW, leg muscle weight, ALB, GLU and LDH.The study demonstrated that chicken LPIN1 has an important effect on body, carcass and organ weight, serum LDH, GLU and ALB level.

Neuroprotective activity of hydroponic Teucrium polium following bilateral ovariectomy.

Ovariectomy is known as "surgical menopause" with decreased levels of estrogen in female rodents. Its reported risks and adverse effects include cognitive impairment. The action of hydroponic Teucrium polium on nucleus basalis of Meynert (bnM) neurons following 6 weeks of ovariectomy was carried out. The analysis of spike activity was observed by on-line selection and the use of a software package. Early and late tetanic, - posttetanic potentiation and depression of neurons to high frequency stimulation of hippocampus were studied. The complex averaged peri-event time and frequency histograms were constructed. The histochemical study of the activity of Са(2+)-dependent acid phosphatase was observed. In conditions of hydroponic Teucrium polium administration, positive changes in neurons and gain of metabolism leading to cellular survival were revealed. The administration of Teucrium polium elicited neurodegenerative changes in bnM.

A morphological-histochemical study of neurodegenerative and regenerative processes in flexor and extensor collaterals of the sciatic nerve after crushing in the presence of PRP-1

A comparative morphological and histochemical study of the dynamics of de- and regenerative processes in the damaged sciatic nerve (SN) area was conducted in rats at different time points after crushing in the presence of proline-rich peptide (PRP-1). We measured the activity of Ca2+-dependent acid phosphatase (AP). At the fifth day after SN crushing on the site of injury, we observed changes in the directions of nerve fibers and disruption of their structure, in particular, swelling of Schwann hollow tubes. Later, we found proliferation of cells of the endoneurium and Schwann cells in the extensor bundle (N. peroneus communis), which promoted recovery of nerve fibers and was accompanied by appearance of the maximum activity AP. We also showed partial recovery of the flexor bundle (N. Gastrocnemius). At 17 days after the trauma, as a result of successful regeneration of the damaged nerve, we observed the recovery of nerve fibers and their structures, which confirms the neuroprotective characteristics of PRP-1

A phosphatidate phosphatase double mutant provides a new insight into plant membrane lipid homeostasis

Phospholipids make up the bulk of most eukaryotic cell membranes, but how their synthesis is regulated remains relatively poorly understood in plants. In our article1 we provide evidence that two Mg2+-dependent phosphatidic acid phosphatase enzymes, called PAH1 and PAH2, are capable of repressing phospholipid biosynthesis at the endoplasmic reticulum in Arabidopsis thaliana. The precise mechanism of repression remains unclear and it does appear to vary in several respects from that already described in Saccharomyces cerevisiae.2,3

Application of a histochemical method for detection of Ca2+ dependent acid phosphatase activity for studies of morpho-functional state of the cell structures in the rat brain

Application of a histochemical method for detection of Ca2+ dependent acid phosphatase activity for studies of morpho-functional state of the cell structures in the rat brain

Significance of the 19‐kDa hemolymph protein HP19 for the development of the rice moth Corcyra cephalonica: morphological and biochemical effects caused by antibody application

The hemolymph protein HP19 of the rice moth, Corcyra cephalonica, mediates the 20-hydroxyecdysone (20E)-dependent acid phosphatase (ACP) activity at a nongenomic level. Affinity-purified polyclonal antibody against HP19 (alphaHP19-IgG) was used in the present study to understand the role of HP19 during the postembryonic development of Corcyra. In the in vitro studies, HP19 action was blocked either by immuno-precipitation using alphaHP19-IgG, prior to its addition to the fat body culture or by the addition of the antibody directly to the culture, along with 20E and hemolymph containing HP19. The alphaHP19-IgG blocked the HP19-mediated 20E-dependent ACP activation. In the in vivo studies, the alphaHP19-IgG was injected into the fully developed last (final/Vth) instar larvae of Corcyra, to complex the HP19 in vivo, in order to block the action of HP19. The injection of alphaHP19-IgG resulted in defective development of larvae, which grew either into non-viable larvae or larval-pupal/pupal-adult intermediates relative to the effect of pre-immune IgG injected controls. The present study shows that HP19 plays an important role in controlling the metamorphosis of Corcyra by regulating the 20E-dependent ACP activity. Coupled with the earlier findings, the ecdysteroid hormone regulates this action at a nongenomic level.

Bone markers and osteoporosis

Diagnosis of a given disease is often the first step to a successful therapy. The use of biochemical markers of bone turnover in osteoporosis is becoming more important due to their capacity to give early information. Many of the new markers are proteins, peptides, or other large biomolecules, usually present at very low concentrations. Bone is a living, growing tissue that turns over at a rate of about 10% a year. It is lergely made up of collagen, that gives the bone its tensile strength and framework, and calcium phosphate, mineralized complex that hardens the framework. After age 24, bone resorption slowly begins to happen faster than bone formation. Bone loss is most rapid in women in the first few year after menopause but continues into the postmenopausal years. Loss although much slowly, also happens in men. In addition to bone porosity, the bone strength is determined by the trabecular microstructure in wich osteoclastic, and osteoblastic activities play an important role. Osteoporosis develops when bone resorption occurs too rapidly and bone formation fails to keep up. Risk factors for osteoporosis involves age, gender, ethnicity, use of certain drugs, exercise, smoking Vit D deficiency, Ca intake, sex hormones, alcohol intake etc. Mineralization markers are serum osteocalcin, bone alkaline phosphatase, serum prokollagen I extention peptides. Markers for the resorption of bone on the other hand are urine N-telopeptide crosslinks, urine deoxy-piridinoline, urine hydroxyproline, tartarate dependent acid phosphatase and Catepsin K. Biochemical markers of bone turnover should be used with BMD for diagnosis.

Identification of coenzyme M biosynthetic 2-phosphosulfolactate phosphatase. A member of a new class of Mg(2+)-dependent acid phosphatases.

Coenzyme M (CoM; 2-mercaptoethanesulfonic acid) is the terminal methyl carrier in methanogenesis. Methanogenic archaea begin the production of this essential cofactor by sulfonating phosphoenolpyruvate to form 2-phospho-3-sulfolactate. After dephosphorylation, this precursor is oxidized, decarboxylated and then reductively thiolated to form CoM. A thermostable phosphosulfolactate phosphohydrolase (EC 3.1.3.-) catalyzing the second step in CoM biosynthesis, was identified in the hyperthermophilic euryarchaeon Methanococcus jannaschii. The predicted ORF MJ1140 in the genome of M. jannaschii encodes ComB, a Mg2+-dependent acid phosphatase that is specific for 2-hydroxycarboxylic acid phosphate esters. Recombinantly expressed purified ComB efficiently hydrolyzes rac-2-phosphosulfolactate, (S)-2-phospholactate, phosphoglycolate and both enantiomers of 2-phosphomalate. In contrast to previously studied phosphoglycolate phosphatases, ComB has a low pH optimum for activity, a narrow substrate specificity and an amino acid sequence dissimilar to any biochemically characterized protein. Like other phosphatases that function via covalent phosphoenzyme intermediates, ComB can catalyze a transphosphorylation reaction. Homologs of comB are identified in all available cyanobacterial genome sequences and in genomes from phylogenetically diverse bacteria and archaea; most of these organisms lack homologs of other CoM biosynthetic genes. The broad and disparate distribution of comB homologs suggests that the gene has been recruited frequently into new metabolic pathways.

Characterization of high- and low-molecular weight zinc-dependent acid phosphatases in bovine liver.

We have purified two forms of Zn2+-dependent acid phosphatase (Zn2+-APase) from bovine liver, both of which require Zn2+ to hydrolyze the substrate p-nitrophenyl phosphate in an acidic environment. The apparent molecular weights of these two forms of Zn2+-APase were estimated to be about 100,000 and 62,000 by gel filtration, and about 44,000 and 31,000 by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, respectively. The low-molecular weight (LMW) Zn2+-APase catalyzed the hydrolysis of myo-inositol-1-phosphate in the presence of 3 mM Mg2+ at physiological pH, but the high-molecular weight (HMW) enzyme did not. The LMW-Zn2+-APase of bovine liver was recognized by polyclonal antibodies developed against the Zn2+-APase of bovine brain, but the HMW-Zn2+-APase was not.

Identity of zinc ion-dependent acid phosphatase from bovine brain and myo-inositol 1-phosphatase

A 62 kDa Zn 2+-dependent acid phosphatase has been purified from bovine brain. The protein was carboxymethylated and then cleaved by endoproteinase Glu-C, trypsin and CNBr. Several fragments were subjected to structural analysis either by using mass spectrometry or automated peptide sequencing. The four sequenced peptides were compared with the known protein sequences contained in the EMBL Data Bank. All four peptide sequences were identical to the corresponding amino-acid sequences present in myo-inositol 1-phosphatase from bovine brain. Furthermore we found that the amino-acid composition of Zn 2+-dependent acid phosphatase purified in our laboratory is very similar to that of myo-inositol 1-phosphatase, and that several peptide fragments have molecular weights (measured by mass spectrometry techniques) identical to those expected for cleavage-fragments originated from the authentic myo-inositol 1-phosphatase. This is one of the key enzymes in the receptor-stimulated inositol phospholipid metabolism and it has been considered as the probable target of Li + ion during LiCl therapy in manic-depressive patients. The comparison of the Zn 2+-dependent acid phosphatase and the Mg 2+-dependent myo-inositol-l-phosphatase activities, measured at different purification steps, shows that the ratio between the two activities was remarkably constant during enzyme purification. We also demonstrated that in the presence of Mg 2+ this enzyme efficiently catalyses the hydrolysis of myo-inositol 1-phosphate, and that the Li + ion inhibits this activity. Furthermore, the thermal treatment of the enzyme causes a time-dependent parallel decrease of both Zn-dependent p-nitrophenyl phosphatase (assayed at pH 5.5) and Mg 2+-dependent myo-inositol-l-phosphatase (assayed at pH 8.0) activities, suggesting the hypothesis that the same protein possesses both these activities.

Zinc-ion-dependent acid phosphatase exhibits magnesium-ion-dependent myo-inositol-1-phosphatase activity.

We have purified bovine brain Zn(2+)-dependent acid phosphatase (Zn(2+)-APase), which requires Zn2+ ions to hydrolyze the substrate p-nitrophenyl phosphate (pNPP) in an acidic environment. The substrate specificity and metal requirement of Zn(2+)-APase at a physiological pH was also studied. The enzyme exhibited hydrolytic activity on myo-inositol-1- and -2-monophosphates, 2'-adenosine monophosphate, 2'-guanosine monophosphate, and the alpha- and beta-glycerophosphates, glucose-1-phosphate, and fructose-6-phosphate in 50 mM Tris-HCl buffer (pH 7.4) in the presence of Mg2+ ions, but not on pNPP and phosphotyrosine. Zn2+, Mn2+ and Co2+ ions were less effective for activation. Among the above substrates, myo-inositol-1-phosphate was the most susceptible to hydrolysis by the enzyme in the presence of 3 mM Mg2+ ions. The enzyme exhibited an optimum pH at around 8 for myo-inositol-1-phosphate in the presence of 3 mM Mg2+ ions. The Mg(2+)-dependent myo-inositol-1-phosphatase activity of the enzyme was significantly inhibited by Li+ ions. The Zn(2+)-dependent p-nitrophenyl phosphatase activity and Mg(2+)-dependent myo-inositol-1-phosphatase activity of the purified enzyme fraction exhibited similar behavior on Sephadex G-100 and Mono Q colomns. These findings suggest that Zn(2+)-APase also exhibits Mg(2+)-dependent myo-inositol-1-phosphatase activity under physiological conditions.

Reduction of low‐molecular‐ weight acid phosphatase activity in Alzheimer brains

Recent studies in Alzheimer brains have shown aberrant protein phosphorylation, suggesting an alteration in protein kinases and/or phosphoprotein phosphatases. In the present study, the activity of acid phosphatase was investigated in samples prepared from postmortem normal human and Alzheimer brains. p-Nitrophenyl phosphate, a nonprotein phosphoester, was used as a substrate for acid phosphatase. The separation profile on Sephadex G-100 gel filtration chromatography revealed that two major forms of high-molecular-weight and low-molecular-weight acid phosphatase were present in the crude extracts of both rat and human brains. Another class of zinc ion (Zn2+)-dependent acid p-nitrophenyl phosphatase was also detected in rat and human brains. In Alzheimer brains, the low-molecular-weight acid phosphatase activity was significantly decreased compared to that in control brains; however, the high-molecular-weight and Zn(2+)-dependent acid phosphatase activity in control and Alzheimer brains was not different. These results suggest that reduced activity of the low-molecular-weight acid phosphatase, which possesses phosphotyrosine protein phosphatase activity, might be linked to aberrant protein tyrosine phosphorylation found in Alzheimer brains.

Purification and characterization of zinc-dependent acid phosphatase from bovine brain.

Zn(2+)-Dependent acid phosphatase (Zn(2+)-APase) was purified to homogeneity from bovine brain. The apparent molecular weight of the enzyme was estimated to be about 62000 by gel filtration and 31000 by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The enzyme exhibited an isoelectric point of approximately 4.8. The enzyme required Zn2+ ions for catalytic activity, but other cations had little or no effect. The maximum enzyme activity was obtained in the presence of about 5 mM of Zn2+ at pH 5.5 in 50 mM 2-(N-morpholino)ethanesulfonic acid-NaOH buffer. The enzyme significantly catalyzed the hydrolysis of p-nitrophenyl phosphate, phenyl phosphate, and phosphotyrosine. The enzyme was also active for myo-inositol-2-monophosphate and adenosine 2'-monophosphate of the other common phosphate esters tested, though significantly less active than for p-nitrophenyl phosphate. The optimum activity pH of the enzyme was around 5.5 with p-nitrophenyl phosphate and myo-inositol-2-monophosphate. The enzyme was resistant to fluoride ions. Two types of Zn(2+)-APases, a high molecular weight (molecular weight, M(r)., about 110,000) and a low molecular weight (M(r), about 62,000) type, were found to exist in various tissues of rat. Brain, lung, spleen, stomach, heart, skeletal muscle, and erythrocytes contained only the lower molecular weight type. On the other hand, liver and kidney contained mainly the higher molecular weight type, and the small intestine contained significant quantities of the both types.

Acid phosphatases in mammalian tissues. Evidence for the existence of a 57kDa Zn 2+-dependent acid phosphatase form

1. 1. A comparative study of multiple forms of acid phosphatase (AcPase) in various organs of mammals was carried out. 2. 2. These studies indicated that the high-molecular weight AcPase is preferentially expressed by tissues which undergo cell proliferation such as epithelial tissues; on the contrary, the low-molecular weight enzyme seems to be characteristic of highly differentiated tissues such as nervous, muscle and blood erythrocytes. 3. 3. The existence of a new AcPase activated by Zn 2+ ions was observed in all tissues studied with the exception of erythrocytes. 4. 4. The enzyme shows a molecular weight of 57 kDa, is insensitivie to NaF, hydrolyzes p-nitrophenylphosphate and o- c-phenylphosphate; ATP, o-naphthylphosphate and β-glycerolphosphate are also dephosphorylated.

Biochemical responsiveness of a bovine kidney cell line to inorganic mercury.

Mercury compounds are known environmental pollutants. A bovine kidney cell line (MDBK) was used to assess the importance of a variety of biochemical cell functions to mercuric chloride (Hg) cytotoxicity. Mercury concentrations utilized ranged between 1–10 μM and elicited 0–45% cytotoxicity at 24-hr post-exposure. Leucine incorporation into cellular protein decreased in a concentration-dependent manner which paralleled the cytotoxicity. Thymidine incorporation into deoxyribonucleic acid was less sensitive to Hg inhibition. K+-dependent phosphatase (KP), succinate dehydrogenase (SDH) and acid phosphatase (AP) were monitored in surviving cells 24 hr post-exposure and in a cell-free system. The activity of KP was reduced to 50% of control activity following 24 hr exposure of MDBK cells to Hg. The activities of SDH and AP of treated cultures remained at control levels. Measurement of reduced glutathione after 24-hr treatment indicated a marginal elevation (120–176%). In a cell-free system, KP, SDH and AP were sensitive to Hg to varying degrees; KP and SDH were most sensitive with IC50s of 1 and 10 μM Hg, respectively. The importance of the biochemical changes in relation to the developing cytotoxicity are discussed.