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1.
Nitric Oxide ; 47: 1-9, 2015 May 01.
Article in English | MEDLINE | ID: mdl-25683505

ABSTRACT

Ovalbumin (OVA), one of the members of the serpin-superfamily, is the major protein in chicken eggs. Many studies have demonstrated the polymerization ability of OVA but the detailed molecular mechanisms demonstrating its conformational changes accompanying fibril formation are still unclear. This study revealed nitric oxide (NO) induced conformational changes and oligomerization of egg white OVA, resulting in polymerized fibrils. Electron microscopic analysis showed that NO treatment to OVA under mild acidic condition resulted in morphological changes, producing structures similar to the long protein fibrils found in egg white. Spectroscopic analysis and mass spectrometry found that NO-treated OVA contains increased number of ß-sheet, indicating transition from α-helixes to ß-sheets, and S-nitrosylation of OVA cysteine residue 367. Structural modeling showed that S-nitrosocysteine, Cys367NO, is located in the amyloidogenic core region of the C-terminal region, nearby the N-terminal core region where the α-to-ß transition is induced. Such results provide a potential mechanism for non-disease-associated fibril formation of OVA.


Subject(s)
Egg White/chemistry , Nitric Oxide/chemistry , Ovalbumin/chemistry , Animals , Chickens , Models, Molecular , Protein Structure, Secondary
2.
Analyst ; 140(10): 3415-21, 2015 May 21.
Article in English | MEDLINE | ID: mdl-25751504

ABSTRACT

This study reports real-time, in vivo functional measurement of nitric oxide (NO) and carbon monoxide (CO), two gaseous mediators in controlling cerebral blood flow. A dual electrochemical NO/CO microsensor enables us to probe the complex relationship between NO and CO in regulating cerebrovascular tone. Utilizing this dual sensor, we monitor in vivo change of NO and CO simultaneously during direct epidural electrical stimulation of a living rat brain cortex. Both NO and CO respond quickly to meet physiological needs. The neural system instantaneously increases the released amounts of NO and CO to compensate the abrupt, yet transient hypoxia that results from epidural electrical stimulation. Intrinsic-signal optical imaging confirms that direct electrical stimulation elicits robust, dynamic changes in cerebral blood flow, which must accompany NO and CO signaling. The addition of l-arginine (a substrate for NO synthase, NOS) results in increased NO generation and decreased CO production compared to control stimulation. On the other hand, application of the NOS inhibitor, l-N(G)-nitroarginine methyl ester (l-NAME), results in decreased NO release but increased CO production of greater magnitude. This observation suggests that the interaction between NO and CO release is likely not linear and yet, they are tightly linked vasodilators.


Subject(s)
Carbon Monoxide/metabolism , Electric Stimulation , Electrochemistry/methods , Neocortex/metabolism , Nitric Oxide/metabolism , Animals , Arginine/metabolism , Arginine/pharmacology , Enzyme Inhibitors/pharmacology , Epidural Space , Male , NG-Nitroarginine Methyl Ester/pharmacology , Neocortex/drug effects , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/metabolism , Optical Imaging , Rats , Rats, Sprague-Dawley , Time Factors
3.
Int J Mol Sci ; 15(3): 4523-30, 2014 Mar 14.
Article in English | MEDLINE | ID: mdl-24637935

ABSTRACT

Tnfaip8/oxidative stress regulated gene-α (Oxi-α) is a novel protein expressed specifically in brain dopaminergic neurons and its over-expression has been reported to protect dopaminergic cells against OS-induced cell death. In this study, murine C165S mutant Tnfaip8/Oxi-α has been crystallized and X-ray data have been collected to 1.8 Å using synchrotron radiation. The crystal belonged to the primitive orthorhombic space group P21212, with unit-cell parameters a = 66.9, b = 72.3, c = 93.5 Å. A full structural determination is under way in order to provide insights into the structure-function relationships of this protein.


Subject(s)
Apoptosis Regulatory Proteins/chemistry , Apoptosis Regulatory Proteins/genetics , Mutation, Missense , Animals , Apoptosis Regulatory Proteins/metabolism , Crystallization , Crystallography, X-Ray , Electrophoresis, Polyacrylamide Gel , Mice , Mutant Proteins/chemistry , Mutant Proteins/genetics , Mutant Proteins/metabolism , Synchrotrons
4.
J Nanosci Nanotechnol ; 12(7): 5168-72, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22966540

ABSTRACT

The two major circulatory systems, the lymph system and the blood vessel system, play significant roles in controlling embryonic development. The primo-vascular system (PVS) was recently reported as an additional circulatory system in various animals. In this paper, the PVS in a mouse embryo was investigated. The structural characterization of the PVS in the mouse placenta and umbilical cord, which was visualized with the trypan blue staining technique, was focused on. The PVS was well_developed in the mouse placenta area. Using a nanopore-based amperometric oxygen sensor, the oxygen levels at four different areas of the embryonic brain, placenta, blood vessel, and primo-vessel of the PVS were measured. The relatively higher oxygen levels that were measured at the primo-vessels than at the brain and the placenta, while still lower than the oxygen level that was measured at the blood vessels, may suggest a role of PVS in oxygen transport.


Subject(s)
Blood Vessels/embryology , Blood Vessels/physiology , Conductometry/instrumentation , Embryo, Mammalian/blood supply , Embryo, Mammalian/metabolism , Oximetry/instrumentation , Oxygen/metabolism , Animals , Equipment Design , Equipment Failure Analysis , Mice , Nanotechnology/instrumentation , Oxygen Consumption/physiology
5.
Article in English | MEDLINE | ID: mdl-22666285

ABSTRACT

The distribution of partial oxygen pressure (pO(2)) is analyzed for the anterior aspect of the left wrist with an amperometric oxygen microsensor composed of a small planar Pt disk-sensing area (diameter = 25 µm). The pO(2) levels vary depending on the measurement location over the wrist skin, and they are systematically monitored in the analysis for both one-dimensional single line (along the wrist transverse crease) and two-dimensional square area of the wrist region. Relatively higher pO(2) values are observed at certain area in close proximity to the position of acupuncture points with statistical significance, indicating strong relationship between oxygen and acupuncture point. The used oxygen microsensor is sensitive enough to detect the pO(2) variation depending on the location. This study may provide information helpful to understand possible physiological roles of the acupuncture points.

6.
J Am Chem Soc ; 133(45): 18328-42, 2011 Nov 16.
Article in English | MEDLINE | ID: mdl-22023085

ABSTRACT

A new phosphorescent zinc sensor (ZIrF) was constructed, based on an Ir(III) complex bearing two 2-(2,4-difluorophenyl)pyridine (dfppy) cyclometalating ligands and a neutral 1,10-phenanthroline (phen) ligand. A zinc-specific di(2-picolyl)amine (DPA) receptor was introduced at the 4-position of the phen ligand via a methylene linker. The cationic Ir(III) complex exhibited dual phosphorescence bands in CH(3)CN solutions originating from blue and yellow emission of the dfppy and phen ligands, respectively. Zinc coordination selectively enhanced the latter, affording a phosphorescence ratiometric response. Electrochemical techniques, quantum chemical calculations, and steady-state and femtosecond spectroscopy were employed to establish a photophysical mechanism for this phosphorescence response. The studies revealed that zinc coordination perturbs nonemissive processes of photoinduced electron transfer and intraligand charge-transfer transition occurring between DPA and phen. ZIrF can detect zinc ions in a reversible and selective manner in buffered solution (pH 7.0, 25 mM PIPES) with K(d) = 11 nM and pK(a) = 4.16. Enhanced signal-to-noise ratios were achieved by time-gated acquisition of long-lived phosphorescence signals. The sensor was applied to image biological free zinc ions in live A549 cells by confocal laser scanning microscopy. A fluorescence lifetime imaging microscope detected an increase in photoluminescence lifetime for zinc-treated A549 cells as compared to controls. ZIrF is the first successful phosphorescent sensor that detects zinc ions in biological samples.


Subject(s)
Fluorescent Dyes/chemistry , Organometallic Compounds/chemistry , Zinc/analysis , Fluorescent Dyes/chemical synthesis , Humans , Iridium/chemistry , Microscopy, Fluorescence , Organometallic Compounds/chemical synthesis , Quantum Theory , Tumor Cells, Cultured
7.
Anal Chem ; 83(21): 8314-9, 2011 Nov 01.
Article in English | MEDLINE | ID: mdl-21942337

ABSTRACT

As gaseous nitric oxide (NO), a critical and multifaceted biomarker, diffuses easily once released, identifying the precise sources of NO release is a challenge. This study developed a new technique for real-time in vivo direct NO imaging by coupling an amperometric NO nanosensor with scanning electrochemical microscopy. This technique provides three-dimensional information of the NO releasing sites in an intact living mouse brain with high sensitivity and spatial resolution. Immunohistochemical analysis was carried out to confirm the anatomical reliability of the acquired electrochemical NO image. The real-time NO imaging results were well matched with the corresponding immunohistochemical analysis of neuronal NO synthase immunoreactive (nNOS-IR) cells, i.e., NO releasing sites in a living brain. The imaged NO local concentrations were confirmed to be closely related to the location in depth, the size of the nNOS-IR cell, and the intensity of nNOS immunoreactivity. This paper demonstrates the first direct electrochemical NO imaging of a living brain.


Subject(s)
Biosensing Techniques/instrumentation , Brain Chemistry , Electrochemical Techniques/instrumentation , Nanoparticles/chemistry , Neuroimaging/methods , Nitric Oxide/analysis , Animals , Biosensing Techniques/methods , Electrochemical Techniques/methods , Immunoenzyme Techniques , Male , Mice , Neurons/metabolism , Nitric Oxide Synthase Type I/metabolism
8.
Anal Chem ; 82(18): 7618-24, 2010 Sep 15.
Article in English | MEDLINE | ID: mdl-20715758

ABSTRACT

This paper reports a real-time study of the codynamical changes in the release of endogenous nitric oxide (NO) and oxygen (O(2)) consumption in a rat neocortex in vivo upon electrical stimulation using an amperometric NO/O(2) dual microsensor. Electrical stimulation induced transient cerebral hypoxia due to the increased metabolic demands that were not met by the blood volume inside the stimulated cortical region. A NO/O(2) dual microsensor was successfully used to monitor the pair of real-time dynamic changes in the tissue NO and O(2) contents. At the onset of electrical stimulation, there was an immediate decrease in the cortical tissue O(2) followed by a subsequent increase in the cortical tissue NO content. The averages of the maximum normalized concentration changes induced by the stimulation were a 0.41 (±0.04)-fold decrease in the O(2) and a 3.6 (±0.9)-fold increase in the NO concentrations when compared with the corresponding normalized basal levels. The peak increase in NO was always preceded by the peak decrease in O(2) in all animals (n = 11). The delay between the maximum decrease in O(2) and the maximum increase in NO varied from 3.1 to 54.8 s. This rather wide variation in the temporal associations was presumably attributed to the sparse distribution of NOS-containing neurons and the individual animal's differences in brain vasculatures, which suggests that a sensor with fine spatial resolution is needed to measure the location-specific real-time NO and O(2) contents. In summary, the developed NO/O(2) dual microsensor is effective for measuring the NO and O(2) contents in vivo. This study provides direct support for the dynamic role of NO in regulating the cerebral hemodynamics, particularly related to the tissue oxygenation.


Subject(s)
Chemistry Techniques, Analytical/instrumentation , Neocortex/metabolism , Nitric Oxide/metabolism , Oxygen/metabolism , Animals , Electric Stimulation , Electrochemistry , Electrodes , Hypoxia/etiology , Hypoxia/metabolism , Male , Rats , Rats, Sprague-Dawley , Time Factors
9.
J Ethnopharmacol ; 113(2): 191-8, 2007 Sep 05.
Article in English | MEDLINE | ID: mdl-17646068

ABSTRACT

It has been reported that deer antler extract has anti-bone resorptive activity in vivo. However, little is known about the cellular and molecular mechanism of this effect. In this study, we investigated the effects of deer antler extracts on osteoclast differentiation and bone-resorption in vitro. Chloroform extract (CE-C) of deer antler inhibited osteoclast differentiation in mouse bone marrow cultures stimulated by receptor activator of NF-kappaB ligand (RANKL) and macrophage-colony stimulating factor (M-CSF). CE-C suppressed the activation of extracellular signal-regulated kinase (ERK), protein kinase B (PKB/Akt) and inhibitor of kappa B (I-kappaB) by RANKL in osteoclast precursor cells. It also inhibited the bone resorptive activity of differentiated osteoclasts that was accompanied by disruption of actin rings and induction of the apoptosis. These results demonstrate deer antler extract may be a useful remedy for the treatment of bone-resorption diseases such as osteoporosis.


Subject(s)
Antlers/chemistry , Bone Resorption/prevention & control , Cell Differentiation/drug effects , Deer , Osteoclasts/drug effects , Tissue Extracts/pharmacology , Actins/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Animals , Apoptosis/drug effects , Bone Marrow Cells/cytology , Bone Marrow Cells/drug effects , Bone Marrow Cells/metabolism , Bone Resorption/metabolism , Bone Resorption/pathology , Cell Survival/drug effects , Cells, Cultured , Chloroform/chemistry , Dose-Response Relationship, Drug , Extracellular Signal-Regulated MAP Kinases/metabolism , Macrophages/cytology , Macrophages/drug effects , Macrophages/metabolism , Mice , Mice, Inbred C57BL , NF-kappa B/metabolism , Osteoblasts/cytology , Osteoblasts/drug effects , Osteoblasts/metabolism , Osteoclasts/cytology , Osteoclasts/metabolism , Phosphorylation/drug effects , Proto-Oncogene Proteins c-akt/metabolism , RANK Ligand/pharmacology , Tissue Extracts/chemistry , Tissue Extracts/isolation & purification
10.
Exp Neurobiol ; 26(3): 151-157, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28680300

ABSTRACT

Albumin is known to have neuroprotective effects. The protein has a long half-life circulation, and its effects can therefore persist for a long time to aid in the recovery of brain ischemia. In the present study, we investigated the neuroprotective effects of human serum albumin (HSA) on brain hemodynamics. Albumin is administrated using repeated oral gavage to the rodents. Sprague-Dawley rats underwent middle cerebral artery occlusion procedures and served as a stroke model. Afterwards, 25% human serum albumin (1.25 g/kg) or saline (5 ml/kg) was orally administrated for 2 weeks in alternating days. After 2 weeks, the rodents were assessed for levels of brain ischemia. Our testing battery consists of behavioral tests and in vivo optical imaging sessions. Modified neurological severity scores (mNSS) were obtained to assess the levels of ischemia and the effects of HSA oral administration. We found that the experimental group demonstrated larger hemodynamic responses following sensory stimulation than controls that were administered with saline. HSA administration resulted in more significant changes in cerebral blood volume following direct cortical electric stimulation. In addition, the mNSS of the treatment group was lower than the control group. In particular, brain tissue staining revealed that the infarct size was also much smaller with HSA administration. This study provides support for the efficacy of HSA, and that long-term oral administration of HSA may induce neuroprotective effects against brain ischemia.

11.
Oncogene ; 24(23): 3715-25, 2005 May 26.
Article in English | MEDLINE | ID: mdl-15806174

ABSTRACT

Since radiation-induced caspase-dependent apoptosis and ROS generation were partially prevented by HSP25 overexpression, similar to the treatment of control cells with antioxidant agents such as DPI and tiron, questions arise whether radiation-mediated ROS generation contributes to the apoptotic cell death, and also whether HSP25 overexpression can reduce ROS mediated apoptotic cell death. In the present study, radiation-induced cytochrome c release from mitochondria and activation of caspases accompanied by a decrease of mitochondrial membrane potential in Jurkat T cells were shown to be inhibited by mitochondrial complex I inhibitor rotenone, suggesting that mitochondrial ROS might be important in radiation-induced caspase-dependent apoptosis. When HSP25 was overexpressed, effects similar to the treatment of cells with the antioxidants were obtained, indicating that HSP25 suppressed radiation-induced mitochondrial alteration that resulted in apoptosis. Furthermore, activation of p38 MAP kinase by radiation was associated with radiation-induced cell death and ROS production and PKCdelta was an upstream molecule for p38 MAP kinase activation, ROS generation and subsequent caspase-dependent apoptotic events. However, in the HSP25 overexpressed cells, the above-described effects were blocked. In fact, radiation-induced membrane translocation of PKCdelta and tyrosine phosphorylation were inhibited by HSP25. Based on the above data, we suggest that HSP25 downregulates PKCdelta, which is a key molecule for radiation-induced ROS generation and mitochondrial-mediated caspase-dependent apoptotic events.


Subject(s)
Apoptosis/radiation effects , Heat-Shock Proteins/physiology , Neoplasm Proteins/physiology , Protein Kinase C/physiology , Reactive Oxygen Species/metabolism , Enzyme Activation , HSP27 Heat-Shock Proteins , Humans , Jurkat Cells , Mitochondria/physiology , Molecular Chaperones , Phosphorylation , Protein Kinase C-delta , p38 Mitogen-Activated Protein Kinases/metabolism
12.
Exp Neurobiol ; 25(3): 130-8, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27358581

ABSTRACT

Ischemia can cause decreased cerebral neurovascular coupling, leading to a failure in the autoregulation of cerebral blood flow. This study aims to investigate the effect of varying degrees of ischemia on cerebral hemodynamic reactivity using in vivo real-time optical imaging. We utilized direct cortical stimulation to elicit hyper-excitable neuronal activation, which leads to induced hemodynamic changes in both the normal and middle cerebral artery occlusion (MCAO) ischemic stroke groups. Hemodynamic measurements from optical imaging accurately predict the severity of occlusion in mild and severe MCAO animals. There is neither an increase in cerebral blood volume nor in vessel reactivity in the ipsilateral hemisphere (I.H) of animals with severe MCAO. The pial artery in the contralateral hemisphere (C.H) of the severe MCAO group reacted more slowly than both hemispheres in the normal and mild MCAO groups. In addition, the arterial reactivity of the I.H in the mild MCAO animals was faster than the normal animals. Furthermore, artery reactivity is tightly correlated with histological and behavioral results in the MCAO ischemic group. Thus, in vivo optical imaging may offer a simple and useful tool to assess the degree of ischemia and to understand how cerebral hemodynamics and vascular reactivity are affected by ischemia.

13.
Mol Cells ; 39(6): 495-500, 2016 Jun 30.
Article in English | MEDLINE | ID: mdl-27215198

ABSTRACT

We have solved the crystal structure of a predicted fructose-specific enzyme IIB(fruc) from Escherichia coli (EcEIIB(fruc)) involved in the phosphoenolpyruvate-carbohydrate phosphotransferase system transferring carbohydrates across the cytoplasmic membrane. EcEIIB(fruc) belongs to a sequence family with more than 5,000 sequence homologues with 25-99% amino-acid sequence identity. It reveals a conventional Rossmann-like α-ß-α sandwich fold with a unique ß-sheet topology. Its C-terminus is longer than its closest relatives and forms an additional ß-strand whereas the shorter C-terminus is random coil in the relatives. Interestingly, its core structure is similar to that of enzyme IIB(cellobiose) from E. coli (EcIIB(cel)) transferring a phosphate moiety. In the active site of the closest EcEIIB(fruc) homologues, a unique motif CXXGXAHT comprising a P-loop like architecture including a histidine residue is found. The conserved cysteine on this loop may be deprotonated to act as a nucleophile similar to that of EcIIB(cel). The conserved histidine residue is presumed to bind the negatively charged phosphate. Therefore, we propose that the catalytic mechanism of EcEIIB(fruc) is similar to that of EcIIB(cel) transferring phosphoryl moiety to a specific carbohydrate.


Subject(s)
Escherichia coli Proteins/chemistry , Escherichia coli Proteins/metabolism , Escherichia coli/enzymology , Fructose/metabolism , Phosphoenolpyruvate Sugar Phosphotransferase System/chemistry , Phosphoenolpyruvate Sugar Phosphotransferase System/metabolism , Amino Acid Sequence , Catalytic Domain , Conserved Sequence , Crystallography, X-Ray , Cysteine/metabolism , Escherichia coli/chemistry , Models, Molecular , Protein Folding , Protein Structure, Secondary , Substrate Specificity
14.
Biochim Biophys Acta ; 1593(2-3): 219-29, 2003 Feb 17.
Article in English | MEDLINE | ID: mdl-12581866

ABSTRACT

Protein kinase C (PKC) isoforms play distinct roles in cellular functions. We have previously shown that ionizing radiation activates PKC isoforms (alpha, delta, epsilon, and zeta), however, isoform-specific sensitivities to radiation and its exact mechanisms in radiation mediated signal transduction are not fully understood. In this study, we showed that overexpression of PKC isoforms (alpha, delta, epsilon, and zeta) increased radiation-induced cell death in NIH3T3 cells and PKC epsilon overexpression was predominantly responsible. In addition, PKC epsilon overexpression increased ERK1/2 activation without altering other MAP-kinases such as p38 MAPK or JNK. Co-transfection of dominant negative PKC epsilon (PKC epsilon -KR) blocked both PKC epsilon -mediated ERK1/2 activation and radiation-induced cell death, while catalytically active PKC epsilon construction augmented these phenomena. When the PKC epsilon overexpressed cells were pretreated with PD98059, MEK inhibitor, radiation-induced cell death was inhibited. Co-transfection of the cells with a mutant of ERK1 or -2 (ERK1-KR or ERK2-KR) also blocked these phenomena, and co-transfection with dominant negative Ras or Raf cDNA revealed that PKC epsilon -mediated ERK1/2 activation was Ras-Raf-dependent. In conclusion, PKC epsilon -mediated ERK1/2 activation was responsible for the radiation-induced cell death.


Subject(s)
3T3 Cells/radiation effects , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinases/metabolism , Protein Kinase C/metabolism , 3T3 Cells/metabolism , Animals , Cell Death/drug effects , Enzyme Activation , Enzyme Inhibitors/pharmacology , Flavonoids/pharmacology , Mice , Mitogen-Activated Protein Kinase 1/genetics , Mitogen-Activated Protein Kinase 3 , Mitogen-Activated Protein Kinases/genetics , Protein Kinase C/biosynthesis , Protein Kinase C/genetics , Protein Kinase C-epsilon , Proto-Oncogene Proteins c-raf/metabolism , Transfection , ras Proteins/metabolism
15.
J Periodontol ; 76(1): 22-33, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15830634

ABSTRACT

BACKGROUND: Recently, there has been much research done into the regenerative potential of materials used in oriental medicine. In several studies, evidence was found that these materials have an effect on bone regeneration. Among these materials, safflower seeds are of particular interest as they have been used for the treatment of blood stasis, bone fracture, and osteoporosis in traditional Korean medicine. In addition, they are known to have anti-inflammatory effects. The objective of this study is to evaluate the periodontal tissue regenerative effects of a bioabsorbable barrier membrane (polylactide glycolic acid electro-spun non-woven membrane) containing safflower seed extracts applied to surgically created 1-wall intrabony defects in beagle dogs. METHODS: One-wall intrabony defects were surgically created bilaterally at the mesial and distal sides of the mandibular second premolars and mesial side of the fourth premolars. These defects were randomly assigned either to the surgical control group which received a flap operation only or to one of two experimental groups consisting of defects which received a guided tissue regenerative procedure with either a bioabsorbable membrane (PLGA) or a bioabsorbable membrane containing safflower seed extracts (SSE/PLGA). The dogs were sacrificed 8 weeks after the operation, and a comparative histological examination was done. RESULTS: The new cementum formation was 2.49+/-0.41 mm in the surgical control group, 3.22+/-0.35 mm in the PLGA group, and 3.67+/-0.82 mm in the SSE/PLGA group. The extent of new cementum formation in barrier groups was significantly different from the surgical control group (P <0.05). The amount of intrabony cementum was 1.75+/-0.06 mm, 2.40+/-0.33 mm, and 2.70+/-0.81 mm for the surgical control group, the PLGA group, and the SSE/PLGA group, respectively; the amount of infrabony cementum in the barrier groups was significantly different from the surgical control group (P<0.05). The value of the suprabony cementum was 0.73+/-0.48 mm, 0.82+/-0.21 mm, and 0.97+/-0.09 mm for the surgical control group, the PLGA group, and the SSE/PLGA group, respectively, with no significant differences being observed among the treatments. The amount of new alveolar bone formation was 1.74+/-0.25 mm, 2.36+/-0.30 mm, and 2.64+/-0.74 mm for the surgical control group, the PLGA group, and the SSE/PLGA group, respectively, with a significant difference exhibited between the surgical control group and other groups (P <0.05). Superficial root resorption was often observed, but ankylosis was not present. CONCLUSION: Our results suggest that surgical application of polylactide glycolic acid non-woven membrane with or without safflower seed extract could promote the regeneration of alveolar bone and cementum in intrabony periodontal defects.


Subject(s)
Absorbable Implants , Biocompatible Materials , Bone Regeneration/drug effects , Carthamus tinctorius , Guided Tissue Regeneration, Periodontal/methods , Alveolectomy , Animals , Dogs , Seeds , Statistics, Nonparametric
16.
J Tissue Eng Regen Med ; 9(4): 435-46, 2015 Apr.
Article in English | MEDLINE | ID: mdl-23166016

ABSTRACT

In this study we showed that 2-(trimethylammonium)ethyl (R)-3-methoxy-3-oxo-2-stearamidopropyl phosphate [(R)-TEMOSPho], a derivative of an organic chemical identified from a natural product library, promotes highly efficient differentiation of megakaryocytes. Specifically, (R)-TEMOSPho induces cell cycle arrest, cell size increase and polyploidization from K562 and HEL cells, which are used extensively to model megakaryocytic differentiation. In addition, megakaryocyte-specific cell surface markers showed a dramatic increase in expression in response to (R)-TEMOSPho treatment. Importantly, we demonstrated that such megakaryocytic differentiation can also be induced from primary human CD34(+) haematopoietic stem cells. Activation of the PI3K-AKT pathway and, to a lesser extent, the MEK-ERK pathway appears to be required for this process, as blocking with specific inhibitors interferes with the differentiation of K562 cells. A subset of (R)-TEMOSPho-treated K562 cells undergoes spontaneous apoptosis and produces platelets that are apparently functional, as they bind to fibrinogen, express P-selectin and aggregate in response to SFLLRN and AYPGFK, the activating peptides for the PAR1 and PAR4 receptors, respectively. Taken together, these results indicate that (R)-TEMOSPho will be useful for dissecting the molecular mechanisms of megakaryocytic differentiation, and that this class of compounds represents potential therapeutic reagents for thrombocytopenia.


Subject(s)
Cell Differentiation/drug effects , Hematopoietic Stem Cells/metabolism , Leukemia, Myeloid/metabolism , MAP Kinase Signaling System/drug effects , Megakaryocytes/metabolism , Organophosphates/pharmacology , Humans , K562 Cells , P-Selectin/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Receptor, PAR-1/metabolism , Receptors, Thrombin/metabolism
17.
Biochem Pharmacol ; 67(7): 1239-48, 2004 Apr 01.
Article in English | MEDLINE | ID: mdl-15013839

ABSTRACT

Osteoclasts are multinucleated cells formed by multiple steps of cell differentiation from progenitor cells of hematopoietic origin. Intervention in osteoclast differentiation is considered as an effective therapeutic approach to the treatment for bone diseases involving osteoclasts. In this study, we found that the organic compound (S)-1-lyso-2-stearoylamino-2-deoxy-sn-glycero-3-phosphatidylcholine (SCOH) inhibited osteoclast differentiation. The inhibitory effect of SCOH was observed in mouse bone marrow cell cultures supported either by coculturing with osteoblasts or by adding macrophage colony stimulating factor (M-CSF) and receptor activator of nuclear factor kappaB ligand (RANKL). M-CSF and RANKL activate the ERK, Akt, and NF-kappaB signal transduction pathways, and SCOH suppressed this activation. SCOH also inhibited the bone resorptive activity of differentiated osteoclasts. It attenuated bone resorption, actin ring formation, and survival of mature osteoclasts. Reduced activation of Akt and NF-kappaB and decreased induction of XIAP were observed in mature osteoclasts treated with SCOH. Thus, this novel phosphatidylcholine derivative may be useful for treating bone-resorption diseases.


Subject(s)
Cell Differentiation/drug effects , Lysophosphatidylcholines/pharmacology , Osteoclasts/drug effects , Protein Serine-Threonine Kinases , Actins/metabolism , Animals , Bone Resorption/drug therapy , Carrier Proteins/pharmacology , Cells, Cultured , Drug Interactions , Lysophosphatidylcholines/chemistry , Lysophosphatidylcholines/therapeutic use , Membrane Glycoproteins/pharmacology , Mice , Mice, Inbred ICR , NF-kappa B/metabolism , Osteoclasts/cytology , Osteoclasts/metabolism , Proteins/metabolism , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins c-akt , RANK Ligand , Receptor Activator of Nuclear Factor-kappa B , Signal Transduction , X-Linked Inhibitor of Apoptosis Protein
18.
Nutrition ; 20(4): 394-401, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15043858

ABSTRACT

OBJECTIVE: The immunomodulatory effect of deer antler, which is used as traditional medicine, has been known, but the active component of antlers from Cervus elaphus has not been identified. In this study, we identified the immunomodulator from C. elaphus and examined its biological activities on the immune system. METHODS: To identify an immunomodulator, we used bioassay-guided fractionation after silica gel column chromatography. Structural analysis was performed with one- and two-dimensional nuclear magnetic resonance techniques and tandem mass spectrometry coupled with fast atom bombardment. RESULTS: The subfraction, phosphatidylcholines, isolated 70% ethanol extract of C. elaphus induced the proliferation of spleen cells in synergy with concanavalin A. According to the structural analysis, phosphatidylcholines were classified as a family (1,2-alkyl-sn-glycerol-3-phosphocholines) containing arachidonyl (C20:4), stearoyl (C18:0), oleoyl (C18:1), linoleoyl (C18:2), palmitoyl (C16:0), and myristoyl (C14:0) chains in their fatty acyl chains. Because the unsaturated fatty acids showed an inhibitory effect on the immune system, dialkyl phosphatidylcholines with different chain lengths from C10:0 to C20:0 that stimulate the proliferation of spleen cells were examined extensively. Among other saturated phosphatidylcholines used, dimyristoyl phosphatidylcholine (C14:0) induced the proliferation of spleen cells more efficiently, whereas dimyristoleoyl phosphatidylcholine (C14:1) effected little change in the proliferation of spleen cells. CONCLUSIONS: These data collectively suggest that phosphatidylcholines with saturated fatty acyl chains are immunostimulating factors. They may modify the proliferation of known mitogens. Further, chain length and saturation of the fatty acids may play important roles in the proliferation of spleen cells.


Subject(s)
Antlers/chemistry , Cell Division/drug effects , Concanavalin A/pharmacology , Deer , Phosphatidylcholines/isolation & purification , Phosphatidylcholines/pharmacology , Animals , Drug Synergism , Fatty Acids/chemistry , Immunity/drug effects , Magnetic Resonance Spectroscopy , Male , Mass Spectrometry , Mice , Mice, Inbred C3H , Phosphatidylcholines/chemistry , Spectrometry, Mass, Fast Atom Bombardment , Spleen/cytology
19.
J Periodontol ; 73(12): 1457-66, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12546096

ABSTRACT

BACKGROUND: Recent interest in naturally based products has increased. Various herbal extracts are known to have a variety of medicinal properties. Among the various natural medicines, safflower seeds have beneficial effects on various bone diseases such as bone fracture, osteoporosis, and osteodysplasia. In addition, they are known to have anti-inflammatory effects. The objective of this study was to evaluate the effect of a safflower seed extract (SSE) on the regeneration of periodontal tissue in a preclinical 1-wall model in dogs. METHODS: Preclinical 1-wall periodontal defects were surgically created in the mesial aspect of the maxillary third and mandibular fourth premolar and in the distal aspect of the maxillary first and mandibular second premolar, and were randomly assigned to receive SSE/collagen (SSE/Col), phosphate-buffered saline/collagen (buffer control), or root planing only (surgical control). The created 1-wall defect configuration was 4 mm in depth by 4 mm in width. We selected the segment showing the best activity to the osteoblast cells that was sensitive to the formation of calcified nodules among the SSE fractions extracted from various organic solvents. The animals were euthanized at 8 weeks postsurgery, and block sections of the defects were collected for histologic and histometric analysis. RESULTS: The junctional epithelium migration did not show any statistically significant differences among the treatments. In connective tissue adhesion, the SSE/Col group and the buffer control group showed significant differences compared to the surgical control group. New cementum averaged 3.84 +/- 0.57 mm, 3.75 +/- 0.24 mm, and 1.53 +/- 1.22 mm for the SSE/Col group, the buffer control group, and the surgical control group, respectively, with the SSE/Col and buffer control groups significantly different from the surgical control group (P < 0.05). The amount of intrabony cementum in the SSE/Col group was significantly different (P < 0.01) from the surgical control group, but the amount of suprabony cementum did not demonstrate any statistical difference between the different treatments. The amount of new alveolar bone averaged 2.93 +/- 0.70 mm, 2.10 +/- 0.63 mm, and 1.20 +/- 0.65 mm for the SSE/Col group, the buffer control group, and the surgical control group, respectively. The difference in alveolar bone regeneration between the SSE/Col group and the surgical control group was significantly different (P < 0.01). Root resorption was often observed, but no ankylosis was present. CONCLUSION: Wound conditioning with safflower seed extracts may contribute to bone formation but appears to have unpredictable potential for stimulating periodontal regeneration including new cementum.


Subject(s)
Alveolar Bone Loss/drug therapy , Bone Regeneration/drug effects , Cementogenesis/drug effects , Phytotherapy , Safflower Oil/pharmacology , Safflower Oil/therapeutic use , Analysis of Variance , Animals , Dogs , Oral Surgical Procedures/methods
20.
Arch Pharm Res ; 27(4): 386-9, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15180302

ABSTRACT

Repeated column chromatography of the CHCl3-soluble fraction of Zingiber zerumbet led to the isolation and identification of two aromatic compounds, p-hydroxybenzaldehyde (1) and vanillin (2), and six kaempferol derivatives, kaempferol-3,4',7-O-trimethylether (3), kaempferol-3-O-methylether (4), kaempferol-3,4'-O-dimethylether (5), 4''-O-acetylafzelin (6), kaempferol-3-O-(4-O-acetyl-alpha-L-rhamnopyranoside)], 2'',4''-O-diacetylafzelin (7), kaempferol-3-O-(2,4-O-diacetyl-alpha-L-rhamnopyranoside)], and 3'',4''-O-diacetylafzelin (8), kaempferol-3-O-(3,4-O-diacetyl-alpha-L-rhamnopyranoside)]. The structures of 1-8 were identified by analysis of spectroscopic data as well as by comparison with published values. This is the first report on the isolation of compounds 1-3 from this plant.


Subject(s)
Benzaldehydes/isolation & purification , Flavonoids/isolation & purification , Kaempferols/isolation & purification , Zingiberaceae , Benzaldehydes/chemistry , Flavonoids/chemistry , Kaempferols/chemistry , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Rhizome
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