1.Metabolic flux analysis of L-serine synthesis by Corynebacterium glutamicum SYPS-062.
Xiaomei ZHANG ; Wenfang DOU ; Hongyu XU ; Zhenghong XU
Chinese Journal of Biotechnology 2010;26(10):1363-1371
Corynebacterium glutamicum SYPS-062 was an L-serine producing strain stored at our lab and could produce L-serine directly from sugar. We studied the effects of cofactors in one carbon unit metabolism-folate and VB12 on the cell growth, sucrose consumption and L-serine production by SYPS-062. In the same time, the metabolic flux distribution was determined in different conditions. The supplementation of folate or VB12 enhanced the cell growth, energy synthesis, and finally increased the flux of pentose phosphate pathway (HMP), whereas the carbon flux to L-serine was decreased. The addition of VB12 not only increased the ratio of L-serine synthesis pathway on G3P joint, but also caused the insufficiency of tricarboxylic acid cycle (TCA) flux, which needed more anaplerotic reaction flux to replenish TCA cycle, that was an important limiting factor for the further increasing of the L-serine productivity.
Citric Acid Cycle
;
physiology
;
Corynebacterium glutamicum
;
metabolism
;
Fermentation
;
Folic Acid
;
pharmacology
;
Serine
;
biosynthesis
;
Vitamin B 12
;
pharmacology
2.Cellular uptake and cytotoxicity of modified chitosans as gene carriers.
Hai-Ling ZHANG ; Dun-Wan ZHU ; Jian YANG ; Li-Ping SONG ; Jin-Gen BO ; Kang-De YAO ; Xi-Gang LENG
Acta Academiae Medicinae Sinicae 2006;28(4):486-491
OBJECTIVETo evaluate the effects of arginine modified chitosan or hexadecylated modified chitosan as gene carriers on the cellular uptake by vascular smooth muscle cells and its in vitro cytotoxicity. METHODS Plasmid DNA was labeled with alpha-32P-dATP and complexed with the modified chitosans or unmodified chitosan to form nanoparticle complexes by complex coacervation method. Uptake of all kinds of chitosan/ DNA nanoparticle complexes (CNC) by A10 cells was measured by beta-liquid scintillation counting. The in vitro cytotoxicity of the CNC was evaluated by the 3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay.
RESULTSThe diameters of the CNC ranged from 55.9-174.9 nm and the zeta potentials were from 10. 8 mV for the arginine modified chitosan/DNA nanoparticle complexes (ACNC) to 1.8 mV for the hexadecylated chitosan/DNA nanoparticle complexes (HCNC). The cellular uptake of the modified chitosan/ DNA nanoparticle complexes (MCNC) by A10 cells increased significantly when compared with the unmodified chitosan/DNA nanoparticle complexes (UCNC) (P < 0.05), with the HCNC at N/P ratio of 1:1 and the ACNC at ratio of 8:1 showing the highest cellular uptake (1.3 fold higher than UCNC, P < 0.05). MCNC were much less cytotoxic when compared with Lipofectamine 2000-DNA nanoparticles.
CONCLUSIONDNA nanoparticle complexes prepared with either arginine or hexadecylated modified chitosan can improve the cellular uptake of the DNA, while the in vitro cytotoxicity of both of the modified chitosan is much less than that of Lipofectamine 2000.
Animals ; Antigen-Antibody Complex ; Arginine ; pharmacology ; Chitosan ; chemistry ; pharmacology ; Citric Acid ; analogs & derivatives ; pharmacology ; Cytotoxicity, Immunologic ; DNA ; pharmacology ; Genetic Vectors ; Nanoparticles ; Rats
3.Analysis of nicotine-induced metabolic changes in Blakeslea trispora by GC-MS.
Yang LIU ; You-Ran SHAO ; Xiang-Yu LI ; Zhi-Ming WANG ; Li-Rong YANG ; Yu-Zhou ZHANG ; Mian-Bin WU ; Jian-Ming YAO
Journal of Zhejiang University. Science. B 2020;21(2):172-177
Blakeslea trispora is a natural source of carotenoids, including β-carotene and lycopene, which have industrial applications. Therefore, classical selective breeding techniques have been applied to generate strains with increased productivity, and microencapsulated β-carotene preparation has been used in food industry (Li et al., 2019). In B. trispora, lycopene is synthesized via the mevalonate pathway (Venkateshwaran et al., 2015). Lycopene cyclase, which is one of the key enzymes in this pathway, is a bifunctional enzyme that can catalyze the cyclization of lycopene to produce β-carotene and exhibit phytoene synthase activity (He et al., 2017).
Citric Acid Cycle
;
Fermentation
;
Gas Chromatography-Mass Spectrometry/methods*
;
Lycopene/metabolism*
;
Mucorales/metabolism*
;
Nicotine/pharmacology*
;
beta Carotene/biosynthesis*
4.Effects of ascorbic acid and citric acid on iron bioavailability in an in vitro digestion/ Caco-2 cell culture model.
Ji LEI ; Ming-qiu ZHANG ; Cheng-yu HUANG ; Lin BAI ; Zhong-hu HE
Journal of Southern Medical University 2008;28(10):1743-1747
OBJECTIVETo study the effects of ascorbic acid and citric acid on iron bioavailability using an in vitro digestion/Caco-2 cell culture model and evaluate the validity of this cell model.
METHODSThis model combined in vitro digestion technique with Fe uptake by Caco-2 cells by utilizing an inserted ring attached to a dialysis membrane to simulate the gastrointestinal environment to allow simultaneous food digestion and uptake processes. Ferritin formation in the Caco-2 cells was measured as the indicator of Fe uptake by exposing Caco-2 cells to the digests containing Fe plus ascorbic acid or citric acid.
RESULTSWhen Fe concentration in the digest was below 100 micromol/L, ferritin formation increased with the Fe concentration in the digest. The iron digest containing ascorbic acid exhibited a significant increase in ferritin formation relative to the iron digest containing citric acid. The model was more sensitive to lower iron concentrations when ascorbic acid was present in the digest, while wider range of iron concentration could be assessed by addition of citric acid.
CONCLUSIONSThe in vitro digestion/ Caco-2 cell culture model is a valuable tool for iron bioavailability assessment. Ascorbic acid has a stronger effect than citric acid in promoting iron bioavailability.
Ascorbic Acid ; pharmacology ; Biological Availability ; Caco-2 Cells ; metabolism ; Citric Acid ; pharmacology ; Ferritins ; biosynthesis ; Ferrous Compounds ; pharmacokinetics ; Humans ; Iron ; pharmacokinetics ; Models, Biological
5.Regional Anticoagulation with Citrate is Superior to Systemic Anticoagulation with Heparin in Critically Ill Patients Undergoing Continuous Venovenous Hemodiafiltration.
Joon Sung PARK ; Gheun Ho KIM ; Chong Myung KANG ; Chang Hwa LEE
The Korean Journal of Internal Medicine 2011;26(1):68-75
BACKGROUND/AIMS: Short hemofilter survival and anticoagulation-related life-threatening complications are major problems in systemic anticoagulation with heparin (SAH) for continuous renal replacement therapy (CRRT). The present study examined if regional anticoagulation with citrate (RAC) using commercially available solutions can overcome the associated problems of SAH to produce economical benefits. METHODS: Forty-six patients were assigned to receive SAH or RAC. We assessed the coagulation state, clinical outcomes, and adverse events. A Kaplan-Meier analysis was used to estimate hemofilter life span. The economical benefit related to the prolonged hemofilter survival was examined on the basis of the average daily cost. RESULTS: The mean age of patients was 66.5 +/- 13.8 years and the majority were male (60.9%). While elective discontinuation was most common cause of early CRRT interruption in the RAC group (34.3%, p < 0.01), hemofilter clotting was most prevalent in the SAH group (82.2%, p < 0.01). The patient metabolic and electrolyte control and survival rate were not different between the two groups. When compared with the RAC group, the anticoagulation-associated bleeding was a major complication in the SAH group (15.0% vs. 61.5%, p < 0.01). Regional anticoagulated hemofilters displayed a significantly longer survival time than systemic anticoagulated hemofilters (59.5 +/- 3.8 hr vs. 15.6 +/- 1.3 hr, p < 0.01). Accordingly, the mean daily continuous venovenous hemodiafiltration costs in the RAC and SAH groups were $575 +/- 268 and $1,209 +/- 517, respectively (p < 0.01). CONCLUSIONS: RAC prolonged hemofilter survival, displaying an economical benefit without severe adverse effects. The present study therefore demonstrates that RAC, using commercially available solutions, may be advantageous over SAH as a cost-effective treatment in CRRT.
Adult
;
Aged
;
Anticoagulants/*pharmacology
;
Citric Acid/*pharmacology
;
Critical Illness
;
Female
;
Health Care Costs
;
*Hemodiafiltration/adverse effects/economics/mortality
;
Heparin/*pharmacology
;
Humans
;
Kaplan-Meier Estimate
;
Male
;
Middle Aged
6.The study of anticoagulants selection in platelet-rich plasma preparation.
Lei HUA ; Gui LAI ; Liu ZHENJUN ; Ma GUIE
Chinese Journal of Plastic Surgery 2015;31(4):295-300
OBJECTIVETo investigate the effect of the anticoagulants on PRP quality, so as to clarify the appropriate anticoagulant used in PRP production.
METHODSThe microstructure change of platelets collected via heparin, citrate, acid citrate dextrose (ACD) and citrate-theophylline-adenosine-dipyridamole ( CTAD) was observed by TEM following time course. The extent of spontaneous activation of platelets in four groups was detected by measuring sP-selectin in plasma. The TGF-β1 release amount of activated PRP of four groups was measured.
RESULTSCTAD is superior to other anticoagulants in maintaining the integrity of platelet structures for a long time and preventing platelet spontaneous activation. ACD slightly surpassed heparin and citrate in above two aspects. ACD-PRP and CTAD-PRP released significantly more TGF-β1 compared with heparin and citrate.
CONCLUSIONSThe PRP quality and biological effects were strongly associated with the type of Anticoagulants. ACD and CTAD are optimal anticoagulants in PRP production for they can maintain platelet viability at a high level.
Adenosine ; pharmacology ; Anticoagulants ; pharmacology ; Blood Platelets ; drug effects ; physiology ; Citrates ; pharmacology ; Citric Acid ; pharmacology ; Dipyridamole ; pharmacology ; Drug Combinations ; Glucose ; analogs & derivatives ; pharmacology ; Heparin ; pharmacology ; Platelet Activation ; drug effects ; Platelet-Rich Plasma ; Theophylline ; pharmacology ; Transforming Growth Factor beta1 ; metabolism
7.Short-term effects of citrate on markers of bone metabolism in Chinese blood donor volunteers.
Xiao-Ling CHU ; Jian-Ming HOU ; Hao LIN ; Hong-Keng LIN ; Jia ZENG ; Guo-Long CHEN ; Cen CHEN ; Juan LIN ; Ying CHEN
Journal of Experimental Hematology 2010;18(3):785-789
This study was purposed to investigate the short-term effects of citrate administration on bone metabolism in the healthy blood donor volunteers. A crossover, placebo-controlled trial were conducted on 22 healthy blood donor volunteers. The volunteers received either a standardized infusion of citrate at 1.5 mg/(kg.min) or the equal volume of placebo normal saline, were washout for 2-3 weeks. During washout serial blood samples were collected and analyzed for bone biochemical markers and electrolytes, such as bone formation marker osteocalcin (OC), bone resorption marker carboxyterminal telopeptide of type I collagen (CTX), intact parathyroid hormone ((i)PTH), ionized calcium ((i)Ca(2+)) and phosphorus (P(i)). Serial urine samples were collected and analyzed for Ca(2+), P(i) and creatinine concentration. The results showed that compared with placebo group, infusion of citrate increased serum levels of OC and CTX (p < 0.0001). The greatest increase of OC and CTX levels occurred at the completion of the intervention. The increment of CTX was higher than OC (p = 0.02), and the OC/CTX ratio decreased (p < 0.01). Infusion of citrate also induced profound increase in serum (i)PTH level (p < 0.0001) and urinary calcium excretion (p < 0.0001), and decrease in serum (i)Ca(2+) (p < 0.0001) and P(i) (p < 0.01) levels. The decrease of (i)Ca(2+) level in female was higher than that in male (p = 0.007), but the changes of (i)PTH, OC, and CTX levels showed no differences between female and male. Changes of OC and CTX levels were closely related to each other (r = 0.56, p < 0.0001) and changes of both markers were negatively correlated with the change of serum (i)Ca(2+) concentration during the citrate intervention(r(OC) = -0.44, r(CTX) = -0.44, p < 0.0001). Increased levels of (i)PTH showed positively correlation with OC (r = 0.34, p = 0.02) and borderline correlation with CTX (r = 0.29, p = 0.06) in male. No such relationship was observed in female. All bone markers and electrolyte levels returned to baseline within 24 hours. It is concluded that the citrate load at the dose as a single platelet apheresis results in profound increase of bone turnover, which is characterized by a short-term increase of bone resorption and excretion of calcium. The possible effect of citrate on bone mass of long-term frequent platelet apheresis donor is worth concerning.
Adult
;
Blood Donors
;
Bone Remodeling
;
drug effects
;
Bone and Bones
;
drug effects
;
metabolism
;
Citric Acid
;
pharmacology
;
Cross-Over Studies
;
Female
;
Humans
;
Male
;
Osteocalcin
;
blood
8.Studies on processing of Fructus Crataegi.
China Journal of Chinese Materia Medica 2004;29(6):501-504
Not only the evolution of the processing of Fructus Crataegi, but also the difference of chemical consitituents, pharmacological effects and clinical application before and after the processing are reviewed, based on 26 references of literature. A way to further study the processing of Fructus Crataegi is provided.
Antidiarrheals
;
therapeutic use
;
Citric Acid
;
analysis
;
Crataegus
;
chemistry
;
Diarrhea
;
drug therapy
;
Drugs, Chinese Herbal
;
chemistry
;
pharmacology
;
therapeutic use
;
Flavones
;
analysis
;
Fruit
;
chemistry
;
Hot Temperature
;
Humans
;
Phytotherapy
;
Plants, Medicinal
;
chemistry
;
Technology, Pharmaceutical
;
methods
;
Trace Elements
;
analysis
9.Effects of Protein Source and Energy Substrates on the In Vitro Development of Bovine Embryos in a Two-step Culture System.
Kwang Taek LIM ; Byeong Chun LEE ; Sung Keun KANG ; Woo Suk HWANG
Journal of Veterinary Science 2003;4(1):73-78
In this study, we examined the effects of a two-step culture system, which involves the use of different culture media for early cleavage and later stage embryos, on the in vitro development of bovine embryos. We also investigated the effect of glucose, phosphate and citrate on the in vitro early developmental period of bovine embryos in a two-step culture system. Moreover, the supplementation of different protein sources (BSA-V, BSA-FAF and FBS) during IVC did not affect the frequency of blastocyst development. Using two-step culture, embryos were cultured in protein-free media for an initial 5 days. This was then followed by the same culture media or an FBS supplemented media. The developmental rates of blastocysts in the FBS containing group were significantly higher than in the replaced with no serum containing group. Embryos cultured in mSOF supplemented with 1.5 mM glucose plus 1.2 mM phosphate were significantly inhibited. The inhibition of developmental competence by glucose plus phosphate was consistent with the existence of 0.5 mM sodium citrate. This study indicates that a two-step culture system, which applies different conditions for early cleavage embryos, i.e., serum-free media, vs. later stage embryos, with serum containing media, may be effective for in vitro production systems. In addition, the developmental competence of bovine embryos was depressed in the presence of glucose plus phosphate as compared to either alone or the absence of both. Therefore, the avoidance of this negative effect should allow more optimal conditions to be developed for in vitro production.
Animals
;
Blastocyst/drug effects/metabolism
;
Cattle/*embryology
;
Citric Acid/pharmacology
;
Culture Media/*chemistry
;
Culture Techniques/*methods
;
Ectogenesis/drug effects
;
Embryo/*drug effects/embryology/metabolism
;
Embryonic and Fetal Development/drug effects
;
*Energy Metabolism
;
Female
;
Fertilization in Vitro
;
Glucose/pharmacology
;
Male
;
Phosphates/pharmacology
;
Proteins/*pharmacology
;
Zygote/drug effects/metabolism
10.Urine metabonomic study of intervention effects of Morinda officinalis how. on 'kidney-yang deficiency syndrome'.
Zhong-jie ZOU ; Yuan-yuan XIE ; Meng-juan GONG ; Bin HAN ; Shu-mei WANG ; Sheng-wang LIANG
Acta Pharmaceutica Sinica 2013;48(11):1733-1737
To investigate the intervention effects of Morinda officinalis How. on 'Kidney-yang deficiency syndrome' induced by hydrocortisone in rats, the metabolic profiles of rat urine were characterized using proton nuclear magnetic resonance and principal component analysis (PCA) was applied to study the trajectory of urinary metabolic phenotype of rats with 'Kidney-yang deficiency syndrome' under administration of M. officinalis at different time points. Meanwhile, the intervention effects of M. officinalis on urinary metabolic potential biomarkers associated with 'Kidney-yang deficiency syndrome' were also discussed. The experimental results showed that in accordance to the increased time of administration, an obvious tendency was observed that clustering of the treatment group moved gradually closed to that of the control group. Eight potential biomarkers including citrate, succinate, alpha-ketoglutarate, lactate, betaine, sarcosine, alanine and taurine were definitely up- or down-regulated. In conclusion, the effectiveness of M. oficinalis on 'Kidney-yang deficiency syndrome' is proved using the established metabonomic method and the regulated metabolic pathways involve energy metabolism, transmethylation and transportation of amine. Meanwhile, the administration of M. officinalis can alleviate the kidney impairment induced by 'Kidney-yang deficiency syndrome'.
Alanine
;
urine
;
Animals
;
Betaine
;
urine
;
Biomarkers
;
urine
;
Citric Acid
;
urine
;
Drugs, Chinese Herbal
;
isolation & purification
;
pharmacology
;
Hydrocortisone
;
Ketoglutaric Acids
;
urine
;
Kidney Diseases
;
chemically induced
;
urine
;
Lactic Acid
;
urine
;
Magnetic Resonance Spectroscopy
;
Male
;
Metabolomics
;
methods
;
Morinda
;
chemistry
;
Plants, Medicinal
;
chemistry
;
Principal Component Analysis
;
Random Allocation
;
Rats
;
Rats, Sprague-Dawley
;
Sarcosine
;
urine
;
Succinic Acid
;
urine
;
Taurine
;
urine
;
Yang Deficiency
;
chemically induced
;
urine