1.Role of Blood Flow vs. O2 Consumption in Nicotinamide-induced Increase pO2 in a Murine Tumor.
Intae LEE ; Moon June CHO ; Thomas J DEMHARTNER ; Leo E GERWECK
Journal of the Korean Society for Therapeutic Radiology 1994;12(1):17-26
We evaluated the effect of nicotinamide on cellular O2 consumption and metabolic status i.e., adenylate phosphates and NAD+ in-vitro, and changes in blood flow in-vivo, to determine whether changes in cellular metabolism or increased oxygen availability, was responsible for increased tumor oxygenation. Thirty min. Pre-incubation of cells with~4mM (=500mg/kg) nicotinamide resulted in no change in cellular O2 consumption. Similarly, neither the adenylate phosphates nor the cellular NAD+ levels were altered in the presence of~4mM nicotinamide. In-vivo, nicotinamide (500mg/kg) increased O2availability as estimated by changes in relative tumor blood flow (RBC flux). The changes in RBC flux measured by the laser Doppler method, were tumor volume dependent and increased from~35% in~150mmdegree tumors to~75% in~500mmdegree tumors. In conclusion, these observations indicate a reduction in local tissue O2 consumption is not a mechanism of improved tumor oxygenation by nicotinamide in FsaII murine tumor model. The primary mechanism of increased pO2 appears to be an increased local tumor blood flow.
Laser-Doppler Flowmetry
;
Metabolism
;
Niacinamide
;
Oxygen
;
Phosphates
;
Tumor Burden
2.Effects of phosphate fertilizer on active ingredients and antioxidant activities of Chrysanthemum morifolium.
Dahui LIU ; Wei LIU ; Duanwei ZHU ; Lanping GUO ; Hang JIN ; Zhitian ZUO ; Li LIU
China Journal of Chinese Materia Medica 2010;35(17):2236-2241
OBJECTIVEIn order to provide a scientific fertilizer application for the standardized cultivation, the effects of phosphate (P) fertilizer on the active ingredients and antioxidant activities of Chrysanthemum morifolium were studied.
METHODPot experiment was adopted to study the effects of P supply on the yield and the content of flavonoids, chlorogenic acid, soluble sugar, soluble amino acids and crude protein of C. morifolium flower. And effects of P supply on the hydroxyl radical scavenging activity, superoxide anion radical scavenging activity, and 2, 2-diphenyl-1-picrylhydrazyl hydrate (DPPH) free radical scavenging activity of flower were researched too.
RESULTThe yield of C. morifolium dry flower increased 129. 94% when P fertilizer was applied. Appropriate application of P fertilizer could also significantly improve the content and accumulation of total flavonoids, chlorogenic acid and soluble sugar in C. morifolium. Thus, the inhibition rates of hydroxyl radical, superoxide anion radical and DPPH free radical of C. morifolium was increased. When the level of P supply exceeded 0.20 g P2O5 per plant, P had also negative influence on the yield and the content of active ingredients and the scavenging activity of hydroxyl radical, superoxide anion radical and DPPH free radical of C. morifolium. Furthermore, there were significant positive correlations between the content of total flavonoids and chlorogenic acid and the inhibition rate of hydroxyl radical, superoxide anion radical and DPPH free radical, respectively.
CONCLUSIONAppropriate application of P fertilizer could be beneficial to the increase the active components and antioxidant activity of C. morifolium. And recommended level of P fertilizer is 0.26-0.28 g x kg(-1).
Antioxidants ; analysis ; metabolism ; Chrysanthemum ; chemistry ; metabolism ; Fertilizers ; analysis ; Phosphates ; metabolism ; Plant Extracts ; analysis ; metabolism
3.Effect of phosphate on growth and polysaccharide production by suspension cultures of protocorm-like bodies of Dendrobium huoshanense.
Shao-Tong JIANG ; Ming WEI ; Jian-Ping LUO
Chinese Journal of Biotechnology 2006;22(4):613-618
The effect of inorganic phosphate on cell growth, accumulation of polysaccharides together with nutrient utilization was investigated in suspension cultures of protocorm-like bodies of Dendrobium huoshanense. Thirty-day-old cells were transferred into liquid medium with the inoculum density of 100 g/L cells. The results indicate that the optimal concentration of phosphate in medium for cell growth of protocorm-like bodies of Dendrobium huoshanense was 2.5 mmol/L and biomass was 496.5 g/L (fresh weight). Phosphate was a limited factor for cell growth and there was relationship between the levels of intracellular phosphate and cell growth. 2.5 mmol/L of medium phosphate was beneficial to the absorption of carbohydrate and nitrate source. 0.312 mmol/L of medium phosphate was better for accumulation of polysaccharides and production of polysaccharides was 2.22 g/L at 36 d.
Cell Proliferation
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drug effects
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Dendrobium
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growth & development
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metabolism
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Phosphates
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metabolism
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pharmacology
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Polysaccharides
;
biosynthesis
;
Suspensions
4.The differential expression of Stathmin in the spinal cord tissue of hens exposed to tri-o-cresyl phosphate.
Xue-rong HAN ; Feng-yuan PIAO ; Yan-ning ZHANG ; Xiang-hu WANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2011;29(12):917-920
OBJECTIVETo screen the differently expressed proteins related to regulating the depolymerization of microtubules in the spinal cord of hens exposed to tri-o-cresyl phosphate (TOCP) and to provide target protein evidence for exploring the mechanisms of the delayed neurotoxicology (OPIDN) induced by organophosphorus compounds (OPs).
METHODSForty two Roman hens were randomly divided into three groups, i.e. TOCP group treated with 1000 mg/kg TOCP; intervention group treated with 40 mg/kg phenylmethanesulfonyl fluoride (PMSF) before 1000 mg/kg TOCP treatment and control group treated with tap water. Four hens in each group were sacrificed on the 5th and 20th days after exposure, respectively. Spinal cords were separated and homogenates at low temperature, and the total proteins were extracted. The OPIDN symptoms observed and recorded in the remaining 6 hens in each group. The differently expressed proteins related to regulating the depolymerization of microtubules were screen by two-dimensional electrophoresis and mass spectroscopy (MS).
RESULTSThe OPIDN symptoms appeared on the 5th day after exposure in TOCP group, which were gradually serious with time. The results by two-dimensional electrophoresis and MS showed that the Stathmin expression was downregulated 3.4 times and 2.8 times in TOCP group, respectively, as compared with the control and PMSF intervention groups. However, there was no significant difference of the Stathmin expression between control group and PMSF intervention group.
CONCLUSIONThe Stathmin expression in the spinal cord tissues of hens exposed to TOCP significantly downregulated. Moreover, the downregulated Stathmin expression may be related to excess polymerization of microtubules and the mechanism of OPIDN.
Animals ; Chickens ; Environmental Exposure ; Female ; Spinal Cord ; metabolism ; Stathmin ; metabolism ; Tritolyl Phosphates ; toxicity
5.Tanshinone IIa attenuates vascular calcification through inhibition of NF-κB and β-catenin signaling pathways.
Hui ZHONG ; Dai-Ying LI ; Su-Ying WANG ; Jie-Yi CHEN ; Jia-Xin CHEN ; Xiao TAN ; Yue-Heng WANG ; Yu-Chen XIE ; Dong-Xing ZHU
Acta Physiologica Sinica 2022;74(6):949-958
Tanshinone IIa is a key ingredient extracted from the traditional Chinese medicine Salvia miltiorrhiza (Danshen), and is widely used to treat various cardiovascular diseases. Vascular calcification is a common pathological change of cardiovascular tissues in patients with chronic kidney disease, diabetes, hypertension and atherosclerosis. However, whether Tanshinone IIa inhibits vascular calcification and the underlying mechanisms remain largely unknown. This study aims to investigate whether Tanshinone IIa can inhibit vascular calcification using high phosphate-induced vascular smooth muscle cell and aortic ring calcification model, and high dose vitamin D3 (vD3)-induced mouse models of vascular calcification. Alizarin red staining and calcium quantitative assay showed that Tanshinone IIa significantly inhibited high phosphate-induced vascular smooth muscle cell and aortic ring calcification. qPCR and Western blot showed that Tanshinone IIa attenuated the osteogenic transition of vascular smooth muscle cells. In addition, Tanshinone IIa also significantly inhibited high dose vD3-induced mouse aortic calcification and aortic osteogenic transition. Mechanistically, Tanshinone IIa inhibited the activation of NF-κB and β-catenin signaling in normal vascular smooth muscle cells. Similar to Tanshinone IIa, inhibition of NF-κB and β-catenin signaling using the chemical inhibitors SC75741 and LF3 attenuated high phosphate-induced vascular smooth muscle cell calcification. These results suggest that Tanshinone IIa attenuates vascular calcification at least in part through inhibition of NF-κB and β-catenin signaling, and Tanshinone IIa may be a potential drug for the treatment of vascular calcification.
Animals
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Mice
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NF-kappa B/metabolism*
;
beta Catenin/metabolism*
;
Signal Transduction
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Myocytes, Smooth Muscle/metabolism*
;
Vascular Calcification/metabolism*
;
Phosphates/metabolism*
6.Relation among Calcium Intake, Bone Metabolism Parameters, Serum Protein and Lipids of Female College Students in Chungnam.
Mi Kyeong CHOI ; Chung Ja SUNG ; Mi Hyun KIM
Journal of the Korean Dietetic Association 2000;6(2):108-116
The purpose of this study was to investigate the relationship among calcium intake, blood parameters related with bone metabolism, and serum lipids in healthy adults on self-selected diet. Subjects were consisted of 40 female college students residing in Chungnam. Anthropometric measurements, dietary intake measurements and blood collection were conducted. Serum concentrations of total protein, albumin, alkaline phosphates, leucine amino peptidase, BUN, calcium, inorganic phosphorus, and lipids were measured by biochemical analyzer and ICP spectrometer. The results were as follows. The mean age of subjects was 22.34 years and weight, height and BMI were 52.89kg, 161.29cm and 20.34, respectively. The daily mean energy and calcium intakes were 81.75% and 64.38% of RDA. The mean animal 1:2. The mean serum concentrations were 6.54g/dl(total protein), 4.12g/dl(albumin), 123.24U/iota(alkaline phosphates), 36.59U/iota(leucine amino peptidase), 8.26mg/dl(calcium), 3.29mg/dl(inorganic phosphorus), 60.73mg/dl(triglyceride), 138.49mg/dl(total cholesterol), 65.95mg/dl(HDL-cholesterol), and 60.39mg/dl(LDL-cholesterol). There were no significant differences among calcium intake, bone metabolism parameters, and serum lipids when analyzed by Pearson's correlation coefficient. More systematic studies are required to investigate the roles of calcium in healthy persons on self-selected diets containing different levels of calcium.
Adult
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Animals
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Calcium*
;
Chungcheongnam-do*
;
Diet
;
Female*
;
Humans
;
Leucine
;
Metabolism*
;
Phosphates
;
Phosphorus
7.Effect of Preconditioning by Low-Flow Perfusion on Cardioprotection.
Korean Circulation Journal 2001;31(12):1252-1260
BACKGROUND AND OBJECTIVES: Recent reports suggest that brief periods of low-flow ischemia (lf Isc) and reperfusion (R) before prolonged Isc mimic ischemic preconditioning (IPC) in murine hearts, probably by a preservation of high energy phosphates. MATERIALS AND METHODS: In order to test this hypothesis, Langendorff-perfused isolated rabbit hearts were subjected to 45 min lf Isc (5% of baseline perfusion flow) with lf IPC or not, followed by 120 min R. lf IPC was induced by a single episode of 5 min lf Isc and 10 min R. These were compared with IPC hearts by 5 min no-flow Isc and 10 min R. RESULTS: lf IPC as well as IPC enhanced post-ischemic functional recovery although IPC did not reduce infarct size (Isc control, 37.5+/-3.1, IPC, 16.2+/-1.5, lf Isc, 43.0+/-0.7, and lf IPC, 40.4+/-1.0% of the left ventricle). Myocardial ATP hydrolysis and lactate production during the preischemic, ischemic, and reperfusion periods were not differ between the experimental groups. CONCLUSION: These results suggest that a brief period of lf Isc could not precondition the rabbit heart and the energy metabolism hypothesis may not be a universal mechanism for the cardioprotective effect of IPC.
Adenosine Triphosphate
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Energy Metabolism
;
Heart
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Hydrolysis
;
Ischemia
;
Ischemic Preconditioning
;
Lactic Acid
;
Myocardial Infarction
;
Perfusion*
;
Phosphates
;
Reperfusion
8.Long-term observation for osseointegriation of calcium 'phosphate sol-gel coating on Ti-6Al-4V implants.
Cheng YANG ; Yuan-ying LI ; Li-e MENG ; Jing-xin CHEN ; Yi HUANG
Chinese Medical Sciences Journal 2007;22(3):183-186
OBJECTIVETo observe the long-term impact of calcium phosphate (CaP) sol-gel coating on bone growth around porous-surfaced implant.
METHODSThe porous-surfaced Ti-6Al-4V implants were prepared with the addition of a thin film of CaP sol-gel coating, and implanted into the tibiae of 8 rabbits, each with two implants. Implanted sites were allowed to heal for 2, 8, 12, and 24 weeks, after which specimens were obtained for scanning electron microscope analysis using the freeze-fracture technique.
RESULTSThe sol-gel coated implants recovered by freeze-fracture technique showed extensive bone growth from the endosteum along the implant surface. The bone was in direct contact with the CaP layer. The cement line-like layer was clearly demonstrated to be an intervening electron dense afibrillar layer between the CaP coat and the overlying newly deposited bone. The stability and osseointegration of the porous-surfaced implants seemed not to be affected by the osteoclastic resorption of CaP layer occurred during 24 weeks of healing.
CONCLUSIONBased on the findings in the long-term observation, the addition of a thin layer of CaP promotes an extensive osseointegrated interface between the porous-surfaced Ti-6Al-4V implants and the newly deposited bone.
Animals ; Calcium Phosphates ; metabolism ; Freeze Fracturing ; Gels ; Male ; Microscopy, Electron, Scanning ; Osseointegration ; Prostheses and Implants ; Rabbits ; Titanium
9.Mechanisms of PiT2-loop7 Missense Mutations Induced Pi Dyshomeostasis.
Hao SUN ; Xuan XU ; Junyu LUO ; Tingbin MA ; Jiaming CUI ; Mugen LIU ; Bo XIONG ; Shujia ZHU ; Jing-Yu LIU
Neuroscience Bulletin 2023;39(1):57-68
PiT2 is an inorganic phosphate (Pi) transporter whose mutations are linked to primary familial brain calcification (PFBC). PiT2 mainly consists of two ProDom (PD) domains and a large intracellular loop region (loop7). The PD domains are crucial for the Pi transport, but the role of PiT2-loop7 remains unclear. In PFBC patients, mutations in PiT2-loop7 are mainly nonsense or frameshift mutations that probably cause PFBC due to C-PD1131 deletion. To date, six missense mutations have been identified in PiT2-loop7; however, the mechanisms by which these mutations cause PFBC are poorly understood. Here, we found that the p.T390A and p.S434W mutations in PiT2-loop7 decreased the Pi transport activity and cell surface levels of PiT2. Furthermore, we showed that these two mutations attenuated its membrane localization by affecting adenosine monophosphate-activated protein kinase (AMPK)- or protein kinase B (AKT)-mediated PiT2 phosphorylation. In contrast, the p.S121C and p.S601W mutations in the PD domains did not affect PiT2 phosphorylation but rather impaired its substrate-binding abilities. These results suggested that missense mutations in PiT2-loop7 can cause Pi dyshomeostasis by affecting the phosphorylation-regulated cell-surface localization of PiT2. This study helps understand the pathogenesis of PFBC caused by PiT2-loop7 missense mutations and indicates that increasing the phosphorylation levels of PiT2-loop7 could be a promising strategy for developing PFBC therapies.
Humans
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Cell Membrane
;
Mutation, Missense
;
Phosphates/metabolism*
;
Sodium-Phosphate Cotransporter Proteins, Type III/genetics*
10.Phosphatidylinositol phosphates directly bind to neurofilament light chain (NF-L) for the regulation of NF-L self assembly.
Sung Kuk KIM ; Ho KIM ; Yong Ryoul YANG ; Pann Ghill SUH ; Jong Soo CHANG
Experimental & Molecular Medicine 2011;43(3):153-160
Phosphatidylinositol phosphates (PtdInsPs) are ubiquitous membrane phospholipids that play diverse roles in cell growth and differentiation. To clarify the regulation mechanism acting on neurofilament light chain (NF-L) self assembly, we examined the effects of various PtdInsPs on this process. We found that PtdInsPs, including PI(4,5)P2, directly bind to the positively charged Arg54 of murine NF-L, and this binding promotes NF-L self assembly in vitro. Mutant NF-L (R53A/R54A) proteins lacking binding affinity to PtdInsPs did not have the same effect, but the mutant NF-L proteins showed greater self assembly than the wild-type in the absence of any PtdInsP. These results collectively suggest that Arg54 plays a pivotal role in NF-L self assembly by binding with PtdInsPs.
Animals
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Fluorescent Antibody Technique
;
Mice
;
Mutation/genetics
;
Neurofilament Proteins/genetics/*metabolism
;
Phosphatidylinositol Phosphates/*metabolism
;
Phospholipase C gamma/metabolism
;
*Protein Multimerization