Stimulatory Effects of KPR-A148 on Osteoblast Differentiation and Bone Regeneration

BACKGROUND: Xanthine derivatives have been used to treat a variety of medical conditions including respiratory disease and neural degeneration. However, few studies have reported their effects on bone regeneration. Therefore, we investigated the effects of KPR-A148, a synthetic xanthine derivative on osteoblast differentiation in vitro and bone regeneration in vivo. METHODS: The cytotoxicity of KPR-A148 was evaluated using MC3T3-E1 cells by the 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltertrazolium bromide assay. The effects of KPR-A148 on osteoblast differentiation were examined by alkaline phosphatase staining, Alizarin red S staining, and real-time PCR of osteoblast differentiation marker genes. To investigate the effects of KPR-A148 on in vivo bone regeneration, a KPR-A148-containing collagen sponge was implanted into a mouse calvarial defect and KPR-A148 was injected twice, weekly. Bone regeneration was evaluated quantitatively by micro-CT and qualitatively by hematoxylin and eosin, as well as Masson's Trichrome staining. RESULTS: KPR-A148 did not show toxicity in the MC3T3-E1 cells and promoted osteoblast differentiation in a concentration-dependent manner. 10 µM of KPR-A148 showed the most significant effect on alkaline phospatase staining and matrix mineralization. KPR-A148 increased the expression of osteoblast marker genes in both the early and late stages of differentiation. In addition, KPR-A148 significantly induced new bone formation in the calvarial defect model. CONCLUSION: These results demonstrate that KPR-A148 strongly induces osteoblast differentiation and new bone formation. Therefore, it could be used as a potential therapeutic agent for regenerating bone following its destruction by disease or trauma.

Pre- and Postsynaptic Actions of Reactive Oxygen Species and Nitrogen Species in Spinal Substantia Gelatinosa Neurons

Reactive oxygen species (ROS) and nitrogen species (RNS) are involved in cellular signaling processes as a cause of oxidative stress. According to recent studies, ROS and RNS are important signaling molecules involved in pain transmission through spinal mechanisms. In this study, a patch clamp recording was used in spinal slices of rats to investigate the action mechanisms of O₂˙⁻ and NO on the excitability of substantia gelatinosa (SG) neuron. The application of xanthine and xanthine oxidase (X/XO) compound, a ROS donor, induced inward currents and increased the frequency of spontaneous excitatory postsynaptic currents (sEPSC) in slice preparation. The application of S-nitroso-N-acetyl-DLpenicillamine (SNAP), a RNS donor, also induced inward currents and increased the frequency of sEPSC. In a single cell preparation, X/XO and SNAP had no effect on the inward currents, revealing the involvement of presynaptic action. X/XO and SNAP induced a membrane depolarization in current clamp conditions which was significantly decreased by the addition of thapsigargin to an external calcium free solution for blocking synaptic transmission. Furthermore, X/XO and SNAP increased the frequency of action potentials evoked by depolarizing current pulses, suggesting the involvement of postsynaptic action. According to these results, it was estblished that elevated ROS and RNS in the spinal cord can sensitize the dorsal horn neurons via pre- and postsynaptic mechanisms. Therefore, ROS and RNS play similar roles in the regulation of the membrane excitability of SG neurons.

The potential renoprotection of xanthine oxidase inhibitors: Febuxostat versus allopurinol

No abstract available.

Caffeine in Brazil: intake, socioeconomic and demographic determinants, and major dietary sources

Background: The objectives of the study were to describe caffeine intake by 10 years of age or older Brazilian individuals and to investigate possible associations with demographic and socioeconomic determinants as well as the major dietary sources. Methods: The data used are from the personal food consumption module (n= 34,003) of a country-representative household budget survey. Consumed foods and beverages were identified during the application of food diaries. Caffeine contents in food and beverage sources were obtained primarily in national publications. Multivariate regressions were calculated to assess the correlations between population factors and caffeine intake. Results: The daily intake per person was estimated as 115.7 mg, ranging from 84.7 mg, for 10­13 years of age children and adolescents, to 139.8 mg, for individuals with no education. The percentage of individuals whom diet reveals daily caffeine intake higher than 400 mg is up to 3.0 %, according to age groups. Males and individuals living in the Northeast or South regions or in the states of Minas Gerais, Rio de Janeiro, and Espírito Santo are likely to ingest higher contents of the substance. The major dietary sources are coffee (63.1 %) and coffee with milk (24.9 %), cola soft drinks (3.6 %) and yerba mate (1.9 %).Conclusions: Caffeine intake in Brazil is below the recommended limit reference value for adults, and the percentage of individuals whom diet reveals excessive content of caffeine is low. Thus, excessive caffeine intake may not be a health issue in Brazil and depends on the domicile and gender. The major source in the Brazilian diet is coffee.

Effects of Reactive Oxygen Species and Nitrogen Species on the Excitability of Spinal Substantia Gelatinosa Neurons

Reactive oxygen species (ROS) and nitrogen species (RNS) are both important signaling molecules involved in pain transmission in the dorsal horn of the spinal cord. Xanthine oxidase (XO) is a well-known enzyme for the generation of superoxide anions (O₂˙⁻), while S-nitroso-N-acetyl-DL-penicillamine (SNAP) is a representative nitric oxide (NO) donor. In this study, we used patch clamp recording in spinal slices of rats to investigate the effects of O₂˙⁻ and NO on the excitability of substantia gelatinosa (SG) neurons. We also used confocal scanning laser microscopy to measure XO- and SNAP-induced ROS and RNS production in live slices. We observed that the ROS level increased during the perfusion of xanthine and xanthine oxidase (X/XO) compound and SNAP after the loading of 2',7'-dichlorofluorescin diacetate (H₂DCF-DA), which is an indicator of intracellular ROS and RNS. Application of ROS donors such as X/XO, β-nicotinamide adenine dinucleotide phosphate (NADPH), and 3-morpholinosydnomimine (SIN-1) induced a membrane depolarization and inward currents. SNAP, an RNS donor, also induced membrane depolarization and inward currents. X/XO-induced inward currents were significantly decreased by pretreatment with phenyl N-tert-butylnitrone (PBN; nonspecific ROS and RNS scavenger) and manganese(III) tetrakis(4-benzoic acid) porphyrin (MnTBAP; superoxide dismutase mimetics). Nitro-L-arginine methyl ester (NAME; NO scavenger) also slightly decreased X/XO-induced inward currents, suggesting that X/XO-induced responses can be involved in the generation of peroxynitrite (ONOO⁻). Our data suggest that elevated ROS, especially O₂˙⁻, NO and ONOO⁻, in the spinal cord can increase the excitability of the SG neurons related to pain transmission.

Establishment of double targets of high throughput screening model for xanthine oxidase inhibitors and superoxide anion scavengers / 药学学报

A double targets of high throughput screening model for xanthine oxidase inhibitors and superoxide anion scavengers was established. In the reaction system of xanthine oxidase, WST-1 works as the probe for the ultra oxygen anion generation, and product uric acid works as xanthine oxidase activity indicator. By using SpectraMax M5 continuous spectrum enzyme sign reflectoscope reflector, the changes of these indicators' concentration were observed and the influence factors of this reaction system to establish the high throughput screening model were studied. And the model is confirmed by positive drugs. In the reaction system, the final volume of reaction system is 50 μL and the concentrations of xanthine oxidase is 4 mU x mL(-1), xanthine 250 μmol x L(-1) and WST-1 100 μmol x L(-1), separately. The Z'-factor of model for xanthine oxidase inhibitors is 0.537 4, S/N is 47.519 9; the Z'-factor of model for superoxide anion scavengers is 0.507 4, S/N is 5.388 9. This model for xanthine oxidase inhibitors and superoxide anion scavengers has more common characteristics of the good stability, the fewer reagent types and quantity, the good repeatability, and so on. And it can be widely applied in high-throughput screening research.

Elevated level of renal xanthine oxidase mRNA transcription after nephropathogenic infectious bronchitis virus infection in growing layers

To assess relationships between xanthine oxidase (XOD) and nephropathogenic infectious bronchitis virus (NIBV) infection, 240 growing layers (35 days old) were randomly divided into two groups (infected and control) of 120 chickens each. Each chicken in the control and infected group was intranasally inoculated with 0.2 mL sterile physiological saline and virus, respectively, after which serum antioxidant parameters and renal XOD mRNA expression in growing layers were evaluated at 8, 15 and 22 days post-inoculation (dpi). The results showed that serum glutathione peroxidase and superoxide dismutase activities in the infected group were significantly lower than in the control group at 8 and 15 dpi (p < 0.01), while serum malondialdehyde concentrations were significantly higher (p < 0.01). The serum uric acid was significantly higher than that of the control group at 15 dpi (p < 0.01). In addition, the kidney mRNA transcript level and serum activity of XOD in the infected group was significantly higher than that of the control group at 8, 15 and 22 dpi (p < 0.05). The results indicated that NIBV infection could cause the increases of renal XOD gene transcription and serum XOD activity, leading to hyperuricemia and reduction of antioxidants in the body.

Reactive Oxygen Species and Nitrogen Species Differentially Regulate Neuronal Excitability in Rat Spinal Substantia Gelatinosa Neurons

Reactive oxygen species (ROS) and nitrogen species (RNS) are implicated in cellular signaling processes and as a cause of oxidative stress. Recent studies indicate that ROS and RNS are important signaling molecules involved in nociceptive transmission. Xanthine oxidase (XO) system is a well-known system for superoxide anions (O2(.-)) generation, and sodium nitroprusside (SNP) is a representative nitric oxide (NO) donor. Patch clamp recording in spinal slices was used to investigate the role of O2(.-) and NO on substantia gelatinosa (SG) neuronal excitability. Application of xanthine and xanthine oxidase (X/XO) compound induced membrane depolarization. Low concentration SNP (10 microM) induced depolarization of the membrane, whereas high concentration SNP (1 mM) evoked membrane hyperpolarization. These responses were significantly decreased by pretreatment with phenyl N-tert-butylnitrone (PBN; nonspecific ROS and RNS scavenger). Addition of thapsigargin to an external calcium free solution for blocking synaptic transmission, led to significantly decreased X/XO-induced responses. Additionally, X/XO and SNP-induced responses were unchanged in the presence of intracellular applied PBN, indicative of the involvement of presynaptic action. Inclusion of GDP-beta-S or suramin (G protein inhibitors) in the patch pipette decreased SNP-induced responses, whereas it failed to decrease X/XO-induced responses. Pretreatment with n-ethylmaleimide (NEM; thiol-alkylating agent) decreased the effects of SNP, suggesting that these responses were mediated by direct oxidation of channel protein, whereas X/XO-induced responses were unchanged. These data suggested that ROS and RNS play distinct roles in the regulation of the membrane excitability of SG neurons related to the pain transmission.

Effects of oxidative stress on endothelial modulation of contractions in aorta from renal hypertensive rats

BACKGROUND: Endothelial dysfunction is linked to exaggerated production of superoxide anions. This study was conducted to examine the effects of oxidative stress on endothelial modulation of contractions in chronic two-kidney, one-clip (2K1C) renal hypertensive rats. METHODS: The 2K1C hypertension was induced by clipping the left renal artery; age-matched rats receiving sham treatment served as controls. Thoracic aortae were isolated and mounted in tissue baths for measurement of isometric tension. RESULTS: Norepinephrine-induced contraction was augmented by the removal of the endothelium, which was more pronounced in sham rats than in 2K1C rats. Nomega-nitro-L-arginine methyl ester, an inhibitor of nitric oxide production, had a similar augmenting effect. Vitamin C inhibited the contraction in aortic rings with intact endothelium from 2K1C rats but not from sham rats. The contraction was also suppressed by treatment with diphenyleneiodonium or apocynin, inhibitors of nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate (NADH/NADPH) oxidase, in the aortae with intact endothelium from 2K1C rats but not in those from sham rats. Superoxide anions generated by xanthine oxidase/hypoxanthine enhanced the contraction in the aortae with intact endothelium from sham rats, but had no effect in 2K1C rats. Enhanced contractile responses to norepinephrine by xanthine oxidase/hypoxanthine in sham rats were reversed by vitamin C. CONCLUSION: These results suggest that the effect on endothelial modulation of endothelium-derived nitric oxide is impaired in 2K1C hypertension. The impairment is, at least in part, related to increased production of superoxide anions by NADH/NADPH oxidase.

Inhibitory Effects of Ethanol Extracts from Nuruk on Oxidative Stress, Melanogenesis, and Photo-Aging

Nuruk contributes to the unique characteristics of Korean alcoholic beverages. In this study, the effects of nuruk extracts (NE) on anti-oxidant characters, melanogenesis, and anti-photoaging activity were investigated. NEs were obtained from the 70% ethanol extracts of six types of nuruk, which have been used in brewing of fermented alcohol beverages in Korea. First, various antioxidant characteristics were identified in terms of 2,2'-azino-bis(3-ethylbenzthiozoline-6-sulphonic acid) (ABTS) radical scavenging activity, superoxide dismutase (SOD) expression, and inhibition of xanthine oxidase activity. NE#4 exhibited potent ABTS radical scavenging activity (IC50 = 19.51 microg/mL). Compared with NE#4, relatively lower levels of activity were observed for NE#3 and NE#6, with IC50 values of 90.99 and 76.88 microg/mL, respectively. According to results of western blot analysis for determination of SOD expression in H2O2-treated HepG2 cells, NE#5 and NE#6 induced a dramatic increase in the expression ratio of SOD, compared to the group treated with H2O2 only. Activity of xanthine oxidase, which converts xanthine into uric acid, generating superoxide ions, was inhibited by NE#4 and NE#6 in a dose-dependent manner. NE#4 induced significant inhibition of mushroom tyrosinase activity. A reduction in cellular melanin contents of 80% was observed in B16F1 melanocytes treated with NE#5 and NE#6; these effects were similar to those of arbutin at 100 microM. In addition, gelatin zymography and reverse transcription-PCR analysis were performed for assessment of anti-photoaging activity of Nuruk. Treatment with NE#6 resulted in dramatically inhibited activities of matrix metalloproteinase (MMP)-2/-9, suppressed expression of MMP-1, and increased expression of type-1 procollagen. Results of gelatin zymography for NE#4 and NE#5 were similar, to a slightly lesser degree. These results suggest the potential of NE#4 and NE#6 as natural ingredients for use in functional foods and cosmetics.

Assessment of Antioxidant and Phenolic Compound Concentrations as well as Xanthine Oxidase and Tyrosinase Inhibitory Properties of Different Extracts of Pleurotus citrinopileatus Fruiting Bodies

Cellular damage caused by reactive oxygen species has been implicated in several diseases, thus establishing a significant role for antioxidants in maintaining human health. Acetone, methanol, and hot water extracts of Pleurotus citrinopileatus were evaluated for their antioxidant activities against beta-carotene-linoleic acid and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, reducing power, ferrous ion-chelating abilities, and xanthine oxidase inhibitory activities. In addition, the tyrosinase inhibitory effects and phenolic compound contents of the extracts were also analyzed. Methanol and acetone extracts of P. citrinopileatus showed stronger inhibition of beta-carotene-linoleic acid compared to the hot water extract. Methanol extract (8 mg/mL) showed a significantly high reducing power of 2.92 compared to the other extracts. The hot water extract was more effective than the acetone and methanole extracts for scavenging DPPH radicals. The strongest chelating effect (92.72%) was obtained with 1.0 mg/mL of acetone extract. High performance liquid chromatography analysis detected eight phenolic compounds, including gallic acid, protocatechuic acid, chlorogenic acid, ferulic acid, naringenin, hesperetin, formononetin, and biochanin-A, in an acetonitrile and hydrochloric acid (5 : 1) solvent extract. Xanthine oxidase and tyrosinase inhibitory activities of the acetone, methanol, and hot water extracts increased with increasing concentration. This study suggests that fruiting bodies of P. citrinopileatus can potentially be used as a readily accessible source of natural antioxidants.

Comparation study on quality of different population of wild and breeding Whitmania pigra / 中国中药杂志

<p><b>OBJECTIVE</b>To examine the quality of Whitmania pigra from the different populations to provide the basis for new species selection.</p><p><b>METHOD</b>The contents of the moisture, alcohol extractive, total ash, acid-insoluble ash, and the activity of antiplatelet aggregation enzyme of wild and the breeding W. pigra were determined by the methods were determined in Chinese Pharmacopoeia (2005 edition). The contents xanthine and hypoxanthine by HPLC.</p><p><b>RESULT</b>It showed that the contents of the alcohol extractive, total ash, acid-insoluble ash, antiplatelet aggregation enzyme, and xanthine and hypoxanthine content of the breeding population in Nanjing are lations. Many quality indexes of the breeding in Zhejiang Tongxiang base were beffer than the wild.</p><p><b>CONCLUSION</b>The breeding W. pigra are good in quality, It suggested large-scale promotion of aquaculture.</p>

Measurement of Purine Contents in Korean Alcoholic Beverages / 대한류마티스학회지

OBJECTIVE: Gout is one of the most common forms of inflammatory arthritides among men, which is caused primarily by chronic hyperuricemia. Although pharmacological therapy is the mainstay treatment to manage gout, limiting the consumption of dietary purine is also important. Several epidemiological studies have reported that alcohol consumption is closely related to hyperuricemia and gout. The objective of this study was to determine the purine content in common Korean alcoholic beverages using high performance liquid chromatography (HPLC) to provide a dietary guideline for those with hyperuricemia or gout. METHODS: Thirty-five alcoholic beverages were analyzed. Blindly labeled samples of each alcoholic beverage were degassed and frozen. The sample preparation prior to HPLC followed the methods of Japanese researchers. HPLC was performed to analyze adenine, guanine, hypoxanthine, and xanthine content in the alcoholic beverages. RESULTS: The standard curves were linear for all purines. Purine contents were as follows: beer (42.26~146.39 micromol/L, n=12), medicinal wine (8.2 and 40.41 micromol/L, n=2), rice wine (13.19 micromol/L), Makgeolri (11.71 and 24.72 micromol/L, n=2), red wine (0, 6.03, and 17.9 micromol/L, n=3). No purines were found in fruit wine (n=2), Kaoliang (n=1), white wine (n=1), or distilled alcoholic beverages, such as soju (n=10) or whiskey (n=1). CONCLUSION: Among popular Korean alcoholic beverages, beer contained a considerable amount of purines, whereas distilled alcoholic beverages did not. Patients with either gout or hyperuricemia should avoid alcoholic beverages, especially those containing large amounts of purines.

Preoperative pentoxyphylline infusion attenuates surgical immune response and alleviates postoperative pain in a dose-dependent fashion during surgical intensive care stay after panhysterectomy

To evaluate the effect of preoperative administration of Pentoxyphylline [PTX] on immune response to surgery and postoperative [PO] pain after panhystrectomy. Forty-five female patients were allocated in 3 equal groups and received intravenous infusion of 100 ml of plain 0.9% NaCI as placebo [control group] or containing 5 or 10 mg/kg PTX, [groups PTX-5 and PTX-10, respectively]. Infusion was given before induction of anesthesia with slow rate for 30 minutes. Duration of PO analgesia, total dose of PO morphine rescue analgesia and visual analogue scale [VAS] scores were determined for 24 hours PO. Serum levels of interleukin [IL]-10, IL-6 and tumor necrosis factor [TNF]-cc were ELISA estimated preoperatively and at 6, 12 and 24 hours postoperatively during and after their surgical intensive care unit [SICU] stay. Mean total VAS pain scores were significantly lower with significantly longer PO duration of analgesia in PTX-10 compared to controls and to PTX-5 group with non-significant difference between PTX-5 and control groups. Total dose of rescue analgesia was significantly lower in PTX-10 group compared to control group and non-significantly compared to PTX-5 group. Both PTX groups showed significantly lower serum levels of TNF-a and IL-6 and significantly higher serum levels of IL-10 compared to control group with significantly lower serum levels of TNF-a and IL-6 and significantly higher serum levels of IL-10 with PTX-10 compared to PTX-5. The effects of PTX on serum IL-6 levels and IL-10 levels were significantly less at 24-hr samples compared to 12-hr samples. Control group showed significantly higher TNF-alpha and IL-6 and significantly lower IL-10 levels at 24-hr compared to levels 12-hr postoperatively. Preoperative PTX infusion modulates the release of nociceptive cytokines with subsequent reduction of PO pain scores and analgesic consumption in a dose dependant fashion

Reactive oxygen species and N-methyl-D-aspartate receptor-mediated central sensitization in hindlimb ischemia/reperfusion injury-induced neuropathic pain rats / 대한마취과학회지

BACKGROUND: Reactive oxygen species (ROS) contribute to development of neuropathic pain. A neuropathic pain syndrome was produced in rats following prolonged hindpaw ischemia/reperfusion injury, creating an animal model of complex regional pain syndrome-Type I (CRPS-I). This study was designed to evaluate the validity of this model for ROS and pain research. Herein we show superoxide produces N-methyl-D-aspartate (NMDA) mediated mechanical allodynia. METHODS: Male adult SD rats were used for neuropathic pain model. Plasma superoxide production rates of before ischemia (BI) and 5 min after reperfusion (JR) were measured via cytochrome C reduction in the presence of xanthine (without xanthine oxidase, kinetics, 550 nm). Mechanical allodynia was measured in both hindpaws. Activation of NMDA receptor subunit 1 (P-NR1) of lumbar spinal cord (L4-L6) in accordance with the change of allodynia was analyzed by the Western blot. RESULTS: Allopurinol-inhibitable, xanthine oxidase-mediated plasma superoxide production was increased at AR. Mechanical allodynia was present in both hindpaws as early as 1 hr after reperfusion, and lasted at least 1 week. The expression of P-NR1 was the highest at 3 days after reperfusion when the withdrawal threshold was the lowest point. SOD significantly blocked P-NR1 activation. CONCLUSIONS: This study suggests that ischemia/reperfusion injury induced neuropathic pain model is a good candidate for the research fields of ROS and pain mechanism. The generation of ROS, especially superoxide is partly responsible for NMDA-mediated mechanical allodynia.

The Effect of Pentoxifylline on Radiobiological Parameters in the Rat Radiation Myelopathy / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: There is great recent interest in the potential value of using pentoxifylline (3,7-dimethyl-1(5-oxyhexyl)- xanthine, PTX) as an inhibitor of radiation-induced late normal tissue damage. The effects of PTX on the radiobiological parameters (alpha/beta ratio, repair half time T1/2) of radiation myelopathy were studied in a rat model. MATERIALS AND METHODS: Anesthetized Sprague-Dawley rats received irradiation to 2 cm of their cervical spines with using a 6MV LINAC (dose rate: 3 Gy/min). Radiation was administered in single, two, four and eight fractions with a fraction interval of 24 h with or without PTX. PTX was added to the rats' distilled drinking water at a concentration of 2 g/L; the water was consumed ad libitum. After tabulation of the ED(50) (the estimated dose needed to produce 50% paralysis in a group of irradiated animals), alpha/beta could be estimated from the ratio of the slope to the intercept of the reciprocal-dose plot. Subsequently, the repair half time T(1/2) was obtained from the data of the experimental group that received a pair of 7 Gy fractions on each day, separated by intervals of 4 and 8 h. RESULTS: The alpha values calculated for RT alone and RT+PTX were almost the same. We noticed that the beta value for the RT+PTX was lower than that for RT alone. So, the alpha/beta ratio for the RT+PTX was higher. The T(1/2) obtained from monoexponential model was 3.27 and 2.58 h for RT alone and RT+PTX, respectively. CONCLUSION: PTX increased the alpha/beta ratio and it decreased the T(1/2) of radiation myelopathy, suggesting that a decreasing fractionation sensitivity occurred. This implies that PTX, which distinctly acts upon the bending region of the high dose, may be expected to protect the spinal cord with a larger fraction size.

Studies of chemical constituents and their antioxidant activities from Astragalus mongholicus Bunge / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To evaluate the antioxidant activities of different chemical constituents from Astragalus mongholicus Bunge and their protection against xanthine (XA)/xanthine oxidase (XO)-induced toxicity in PC12 cells.</p><p><b>METHODS</b>The compounds of Astragalus mongholicus Bunge were isolated by chromatography and the structures were elucidated on the basis of spectral data interpretation. Their antioxidant activities were detected by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities in a cell-free system. Meanwhile, the effects against XA/XO-induced toxicity were assessed using MTT assay in PC12 cells.</p><p><b>RESULTS</b>Ten principal constituents were isolated and identified as formononetin (I), ononin (II), calycosin (III), calycosin-7-O-beta-D-glucoside (IV), 9,10-dimethoxypterocarpan-3-O-beta-D-glucoside (V), adenosine (VI), pinitol (VII), daucosterol (VIII), beta-sitoster (IX) and saccharose (X) from Astragalus mongholicus Bunge. The compounds I, III, and IV scavenged DPPH free radicals in vitro. Formononetin and calycosin were found to inhibit XA/XO-induced cell injury significantly, with an estimated EC50 of 50 ng/mL.</p><p><b>CONCLUSION</b>Compound II, VI, and VII are first reported in this plant. Calycosin exhibits the most potent antioxidant activity both in the cell-free system and in the cell system.</p>

Lesch-Nyhan syndrome and purine and pyrimidine metabolism didorders / 한양의대학술지

Purine & pyrimidine nucleotides are basic constituents of cellular DNA and RNA polynucleotides. Their function includes regulation of cell metabolism and function, energy conservation and transport and formation of coenzymes and active intermediates of phospholipids and carbohydrate metabolism. The origin of cellular purines and pyrimidines is almost exclusively endogenous source, and the dietary purines play only a minor role. Diagnostic and clinical markers of purine and pyrimidine nucleotide disorders are the level of uric acid, xanthine, hypoxanthine, orotic acid, uracil, thymine, dihydrouracil, dihydrothymine, and succinyladenosine. Clinical manifestations of purine and pyrimidine metabolic disorders are crystalluria and acute renal failure, infections, failure to thrive, and anemia. One of purine metabolic disorders, Lesch-Nyhan disease, is X-linked recessive disorder, presenting motor delay, cerebral palsy, involuntary movements, self-injurious behavior, hyperurcemia, uricosuria, urinary calculi and gouty arthritis. Hypoxanthine-guanine phosphoribosyl transferase(HPRT) is deficient.

Protective Effect of Heat Shock Protein 70 Against Oxidative Stresses in Human Corneal Fibroblasts

We evaluated DNA protection effect of heat shock protein (HSP) against cytotoxic effects of exogenous nitric oxide (NO) and reactive oxygen intermediate (ROI). Cultured human corneal fibroblasts were divided into 4 groups. Control (Group I) was not exposed to a sub-lethal heat treatment. Other 3 groups were exposed to 43 degrees C for 1 hr, then incubated at 37 degrees C during different duration (1, 6, 24 hr, Group II, III, IV, respectively). Expression pattern of HSP 70 was analyzed by Western blot. Cell viability was measured by MTT assay and the relationship between HSP 70 expression and DNA damage was examined by terminal deoxyribonucleotidyl transferase mediated dUTP-digoxigenin nick and labeling (TUNEL) stain and single cell gel electrophoresis. Expression pattern of HSP 70 was dependent on recovery times. Cell viability following heat treatment was significantly increased and the TUNEL positive cell number was decreased at 6 hr. In single cell gel electrophoresis, tail moments were increased in a dose-dependent manner by SNAP and X/XO. Following heat treatment, tail moments showed decreased significantly at 6 hr. These results suggest that induction of HSP 70 by sub-lethal heat treatment is closely related with cytoprotective effects against oxidative stresses in human corneal fibroblasts.