Comparative Evaluation of the Radioprotective Properties of Copper Chlorophyllin, Trolox, and Indralin in an Experiment on Mice.

The radioprotective properties of copper chlorophyllin (100 and 150 µg/g), the standard antioxidant trolox (100 and 200 µg/g), and the standard radioprotector indralin (100 and 150 µg/g) were compared in male ICR mice (CD-1) subjected to whole-body irradiation (X-ray radiation) in doses of 6, 6.5, and 6.75 Gy. Animal survival was analyzed using the Kaplan-Meier method, and the significance of differences was evaluated using the log-rank test method. Dose change factors determined using the Phinney probit analysis were 1.1, 1.0, and 1.8 for chlorophyllin, trolox, and indralin at a dose of 100 µg/g body weight, respectively. The insignificant radioprotective properties of chlorophyllin and their absence in trolox when administered prophylactically do not rule out their possible radioprotective properties like a radiomodulator that protects the body after irradiation.

Assessment of the Acute Toxicity of Chlorophyllin and Trolox for the Possibility of Studying Their Radioprotective Properties.

The acute toxicity of chlorophyllin and trolox upon intraperitoneal injection of their solutions was studied in male ICR (CD-1) mice. The LD50 of chlorophyllin was found to be 633±37.2 µg/g body weight, which is lower than the LD50 of established radioprotectors. Trolox is technically non-toxic under the conditions of our study. The results obtained highlight the need for a detailed study of the radioprotective properties of trolox and chlorophyllin.

Facile synthesis of tantalum decorated on iron selenide with nitrogen-doped graphene hybrid for the sensitive detection of trolox in berries: Density functional theory interpretation.

This work presents a hydrothermal method followed by a sonochemical treatment for synthesizing tantalum decorated on iron selenide (Ta/FeSe2) integrated with nitrogen-doped graphene (NGR) as a susceptible electrode material for detecting trolox (TRX) in berries samples. The surface morphology, structural characterizations, and electrochemical performances of the synthesized Ta/FeSe2/NGR composite were analyzed via spectrophotometric and voltammetry techniques. The GCE modified with Ta/FeSe2/NGR demonstrated an impressive linear range of 0.1 to 580.3 µM for TRX detection. Additionally, it achieved a remarkable limit of detection (LOD) of 0.059 µM, and it shows a high sensitivity of 2.266 µA µÐœ-1 cm-2. Here, we used density functional theory (DFT) to investigate the structures of TRX and TRX quinone and the locations of energy levels and electron transfer sites. The developed sensor exhibits significant selectivity, satisfactory cyclic and storage stability, and notable reproducibility. Moreover, the practicality of TRX was assessed in different types of berries, yielding satisfactory recoveries.

Electrochemical Detection of Total Antioxidant Capacity (TAC) in Plant Tissues from Different Origins.

Total antioxidant capacity (TAC) is a reliable indicator of antioxidant content in animal and plant samples. The different experimental approaches available allow the determination of TAC using, as a reference, diverse compounds with recognized antioxidant capacities such as Trolox, ascorbic acid, gallic acid, or melatonin. A new portable device, named BRS (BQC redox system), is now commercially available that, through an electrochemical approach, allows the determination of TAC in a simple, fast, reproducible, and robust way. In this chapter, using this portable device, a comparative analysis of the TAC is assayed in different red, citrus, and Solanaceae fruits, several Allium species, and organs of different plant species, including Arabidopsis thaliana. The obtained results demonstrate the versatility of the BRS portable device.

New sesquiterpenoids with neuroprotective effects in vitro and in vivo from the Picrasma chinensis.

Three undescribed sesquiterpenes, designed as pichinenoid A-C (1-3), along with nine known ones (4-12) were isolated from the stems and leaves of Picrasma chinensis. The new isolates including their absolute configurations were elucidated based on extensive spectroscopic methods, single crystal X-ray diffraction, and electronic circular dichroism (ECD) experiments, as well as comparison with literature data. Structurally, compounds 1 and 2 are descending sesquiterpenes, while pichinenoid C (3) is a rare sesquiterpene bearing a 2-methylenebut-3-enoic acid moiety at the C-6 side chain. All the isolated compounds were tested for their neuroprotective effects against the H2O2-induced damage on human neuroblastoma SH-SY5Y cells, and most of them showed moderate neuroprotective activity. Especially, compounds 1, 3-5, and 7 showed a potent neuroprotective effect at 25 or 50 µM. Moreover, the neuroprotective effects of compounds 1 and 4 were tested on a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD) mouse model. Results of western blot and immunofluorescence indicated that compound 4 significantly counteract the toxicity of MPTP, and reversed the expression of tyrosine hydroxylase (TH) in substantia nigra (SN) and striatum (ST) of the mouse brain. Interestingly, western blot data suggested compound 4 also enhanced B-cell lymphoma-2 (Bcl-2) and heme oxygenase 1 (HO-1) expressions in the brain tissues from MPTP damaged mouse.

Unraveling the effects of drying techniques on chaya leaves: Metabolomics analysis of nonvolatile and volatile metabolites, umami taste, and antioxidant capacity.

Chaya (Cnidoscolus chayamansa) leaves are known for their strong umami taste and widespread use as a dried seasoning. This study aimed to assess the impact of different drying methods [freeze drying (FD), vacuum drying, oven drying at 50 °C and 120 °C (OD120) and pan roasting (PR)] on the metabolome using mass spectrometry, umami intensity, and antioxidant properties of chaya leaves. The predominant volatile compound among all samples, 3-methylbutanal, exhibited the highest relative odor activity value (rOAV), imparting a malt-like odor, while hexanal (green grass-like odor) and 2-methylbutanal (coffee-like odor) are the second highest rOAV in the FD and PR samples, respectively. OD120 and PR samples possessed the highest levels of umami-tasting amino acids and 5'-ribonucleotides as well as the most intense umami taste, whereas FD samples exhibited the highest antioxidant capacity. These findings enhance our understanding of the aroma characteristics, umami taste, and antioxidant potential of processed chaya leaves.

Antiradical capacity assay for hydrophobic substances using hemin-catalyzed luminol chemiluminescence in cationic micelles.

Antioxidant substances which can diminish the steady-state concentration of free radicals in vivo are important in the human dietary to diminish the deleterious effects of oxidative stress. As the potential of certain substances as antioxidants is difficult to be verified in vivo, simple chemical in vitro assays which test the potential of substances as antioxidants are of great importance for the screening of new antioxidants. These assays measure the capacity of a substance to suppress free radicals. We describe here an antiradical capacity assay, based on luminol chemiluminescence, in cationic micellar medium, allowing the capacity determination of hydrophobic compounds. The antiradical capacity of antioxidants is determined using the Trolox standard by the measurement of the light emission inhibition area caused by the addition of different antiradical concentrations. The obtained results are compared to the values determined using the scavenging of stable free radicals be the substances and shown to be similar for compounds like uric acid, rutin, and quercetin. However, for vitamin E, the luminol assay results in a considerably higher antiradical capacity than the assay with a stable free radical, which is rationalized by the higher reactivity of the radical generated in the luminol assay and a specific localization of vitamin E in the micellar medium.

Effect of Selected Antioxidants on the In Vitro Aging of Human Fibroblasts.

The modification of the replicative lifespan (RLS) of fibroblasts is of interest both from a knowledge point of view and for the attenuation of skin aging. The effect of six antioxidants at a concentration of 1 µM on the replicative lifespan of human dermal fibroblasts was studied. The nitroxide 4-hydroxy-TEMPO (TEMPOL), ergothioneine, and Trolox extended the replicative lifespan (RLS) (40 ± 1 population doublings (PD)) by 7 ± 2, 4 ± 1, and 3 ± 1 PD and lowered the expression of p21 at late passages. Coumaric acid, curcumin and resveratrol did not affect the RLS . The level of reactive oxygen species (ROS) was decreased or not affected by the antioxidants although TEMPOL and coumaric acid decreased the level of glutathione. Only ergothioneine and resveratrol decreased the level of protein carbonylation. The antioxidants that could prolong the RLS elevated the mitochondrial membrane potential. Protecting the activity of mitochondria seems to be important for maintaining the replicative capacity of fibroblasts.

Elevating sensing capability via dual-atom catalysts boosted luminol cathodic electrochemiluminescence.

BACKGROUND: The advancement of highly sensitive electrochemiluminescence (ECL) biosensors has garnered escalating interest over time. Owing to the distinctive physicochemical attributes, the signal amplification strategy facilitated by functional nanomaterials has achieved notable milestones. Single-atom catalysts (SACs), featuring atomically dispersed metal active sites, have garnered significant attention. SACs offer unprecedented control over active sites and surface structures at the atomic level. However, to fully harness their potential, ongoing efforts focus on strategies to enhance the catalytic performance of SACs, profoundly influencing both the sensitivity and selectivity of SACs-based sensing platforms. RESULTS: In this study, we focused on the synthesis and application of Fe-Co-PNC dual-atom catalysts (DACs) with the incorporation of phosphorus, aiming to enhance catalytic efficiency, particularly in the context of the oxygen reduction reaction (ORR) correlated cathodic luminol ECL. The synergistic effects arising from the combination of Fe and Co in DACs were explored by ECL emission. Comparative studies with Fe-PNC SACs highlighted the superior catalytic performance of Fe-Co-PNC DACs. The ECL sensing platform exhibited excellent sensitivity, which provided a fast detection of Trolox with a wide linear range (0.1 µM-1.0 mM) and a low detection limit (LOD) of 0.03 µM. The platform demonstrated remarkable reproducibility and long-term stability, showcasing its potential for practical biosensing applications. SIGNIFICANCE: This study introduced the novel concept of Fe-Co-PNC DACs. The demonstrated synergistic effects and enhanced catalytic efficiency of DACs offer new avenues for the rational design of advanced catalysts. The successful application in the sensitive detection of Trolox emphasizes their potential significance in biosensing. It not only expands our understanding of SACs but also opens doors for the development of efficient and stable catalysts with broader applications.

Synthesis and Biological Activity of Trolox Amide Derivatives

Abstract A series of Trolox amide derivatives were synthesized by modifying the carboxyl groups of Trolox. Thirty target compounds were obtained and characterized through nuclear magnetic resonance and mass spectrometry. Trolox derivatives were employed to explore the potential structure-antioxidant activity relationships. The antioxidant activities of these compounds were evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP) and hydroxyl radical assays. DPPH scavenging activity test results illustrated that compounds exhibited scavenging activities similar to L-ascorbic acid and Trolox, with compounds 14a, 18a, 24a and 26a in particular exhibiting higher scavenging activities than L-ascorbic acid. The results demonstrated that compounds displayed ABTS scavenging activities similar to L-ascorbic acid and Trolox, with compounds 26a and 29a in particular having potency twofold higher. FRAP assay results indicated that compounds 11a, 19a, 25a, 29a and 30a had activity similar to Trolox. The results revealed that compounds 6a and 19a had similarly high hydroxyl radical-scavenging activities as Trolox. The results of α-glucosidase experiments uncovered that compounds 10a, 25a, 28a and 29a had excellent inhibitory activity, which was similar to that of acarbose and different from Trolox. The results of acetylcholinesterase and butyrylcholinesterase experiments demonstrated that some compounds had weak anticholinesterase activities. 26a and 29a are important Trolox derivatives with better biological activity profiles and deserve further study

Antioxidant Activities, Total Phenolic Content and Colour Parameters in the Aqueous Extracts of Avocado, Banana and Papaya Leaves (Aktiviti Antioksida, Jumlah Kandungan Fenolik dan Parameter Warna dalam Ekstrak Akueus Daun Avokado, Pisang dan Betik) / Jurnal Sains Kesihatan Malaysia

@#Literature has consistently reported that horticultural wastes including leaves, skin, stones and seeds contain substantial amounts of bioactive compounds. Therefore, this study aims to evaluate antioxidant activity, Total Phenolic Content (TPC) and colour parameters in avocado, banana, and papaya leaves. Antioxidant activity of the leaves was determined using Trolox Equivalent Antioxidant Capacity (TEAC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays, TPC was evaluated using Folin-Ciocalteu assay whereas the colour parameters were analysed with a colour picker software. Data analysis was carried out using SPSS version 25.0 of triplicate determinations. Mean differences among the fruit leaves extracts were determined using One-way ANOVA, while the correlations between the studied components were by the Pearson’s Correlation Coefficient test. The TEAC values were in the range of 332.30 ± 18.04 µg Trolox/g D.W. (avocado leaves) to 12217.71 ± 18.04 µg Trolox/g D.W. (banana leaves) while the DPPH radical scavenging activity was from 10.07 ± 3.89% (banana leaves) to 86.70 ± 0.26 % (avocado leaves). Besides, TPC was from 871.33 ± 38.35 µg GAE/g D.W. (papaya leaves) to 1199.08 ± 6.00 µg GAE/g D.W. (avocado leaves). The hue values were from 19º in avocado leaves extract to 37º in banana leaves extract. Results from Pearson’s Correlation Coefficient test revealed that there were no significant correlations between the studied assays. Avocado leaves had the highest DPPH radical scavenging activity and TPC among the three extracts. Findings derived from the present study could be exploited in nutraceuticals formulation.

Antioxidant effect on viability of boar semen cooled to 15°C / Influência de antioxidantes na viabilidade do sêmen suíno resfriado a 15°C

This study aimed to evaluate the addition of Vitamin C, reduced Glutathione and trolox on sperm characteristics of pork refrigerated semen. Six pigs were collected through the technique of gloved hand (10 ejaculates/animals). The semen was diluted in MR-A®. After the previous evaluations, the treatments were added: Control group: diluent only; Vitamin C Group: 200µM/mL Vitamin C; Trolox Group: 200µM/mL Trolox; Glutathione group: 2.5mM/ml Reduced glutathione. The semen was stored in thermal boxes and placed inside the refrigerator at 15oC and evaluated at D0, 12, 48, 72 hours. After 30 hours of incubation, each treatment was divided into two equal fractions and the same concentration of antioxidants was added in one of the parts. The results show that reduced glutathione supplementation preserves sperm motility after 24 hours but also has a higher percentage of acrosome intact in the presence of this antioxidant. There was no effect of adding a second dose of the antioxidants. In conclusion, the addition of reduced Glutathione to the swine semen diluent is a promising alternative for better preservation of sperm characteristics and the addition of the second dose of antioxidants during storage is detrimental to semen.(AU)

Este estudo tem como objetivo avaliar a adição da vitamina C, da glutationa reduzida e do trolox sobre características espermáticas do sêmen refrigerado de suínos. Seis cachaços foram coletados pela técnica de mão enluvada (10 coletas/animal). O sêmen foi diluído em MR-A®. Após as avaliações prévias, os tratamentos foram adicionados: grupo controle: apenas diluidor; grupo vitamina C: 200µM/mL de vitamina C; grupo trolox: 200µM/mL de trolox; grupo glutationa: 2.5mM/mL de glutationa reduzida. O sêmen foi armazenado em caixas térmicas e alocado dentro do refrigerador a 15oC e avaliado nos tempos zero, 12, 48 e 72 horas . Após 30 horas de incubação, cada tratamento foi dividido em duas frações iguais e adicionou-se a mesma concentração de antioxidantes em uma das partes. Os resultados demonstram que a suplementação de glutationa reduzida preserva a motilidade espermática após 24 horas, bem como tem maior percentual de acrossoma intacto na presença desse antioxidante. Não houve efeito ao se adicionar uma segunda dose dos antioxidantes. Em conclusão, o acréscimo da glutationa reduzida ao diluidor de sêmen suíno é uma alternativa promissora para melhor preservação das características espermáticas, e a adição da segunda dose dos antioxidantes durante o armazenamento é prejudicial ao sêmen.(AU)

Moderate Dose of Trolox Preventing the Deleterious Effects of Wi-Fi Radiation on Spermatozoathrough Reduction of Oxidative Stress Damage / 中华医学杂志(英文版)

<p><b>Background</b>The worsening of semen quality, due to the application of Wi-Fi, can be ameliorated by Vitamin E. This study aimed to demonstrate whether a moderate dose of trolox, a new Vitamin E, inhibits oxidative damage on sperms in vitro after exposure to Wi-Fi radiation.</p><p><b>Methods</b>Each of the twenty qualified semen, gathered from June to October 2014 in eugenics clinic, was separated into four aliquots, including sham, Wi-Fi-exposed, Wi-Fi plus 5 mmol/L trolox, and Wi-Fi plus 10 mmol/L trolox groups. At 0 min, all baseline parameters of the 20 samples were measured in sequence. Reactive oxygen species, glutathione, and superoxide dismutase were evaluated in the four aliquots at 45 and 90 min, as were sperm DNA fragments, sperm mitochondrial potential, relative amplification of sperm mitochondrial DNA, sperm vitality, and progressive and immotility sperm. The parameters were analyzed by one-way analysis of variance and Tukey's posttest.</p><p><b>Results</b>Among Wi-Fi plus 5 mmol/L trolox, Wi-Fi-exposed and Wi-Fi plus 10 mmol/L trolox groups, reactive oxygen species levels (45 min: 3.80 ± 0.41 RLU·10·mlvs. 7.50 ± 0.35 RLU·10·mlvs. 6.70 ± 0.47 RLU·10·ml, P < 0.001; 90 min: 5.40 ± 0.21 RLU·10·mlvs. 10.10 ± 0.31 RLU·10·mlvs. 7.00 ± 0.42 RLU·10·ml, P < 0.001, respectively), percentages of tail DNA (45 min: 16.8 ± 2.0% vs. 31.9 ± 2.5% vs. 61.3 ± 1.6%, P < 0.001; 90 min: 19.7 ± 1.5% vs. 73.7 ± 1.3% vs. 73.1 ± 1.1%, P < 0.001, respectively), 8-hydroxy-2'-deoxyguanosine (45 min: 51.89 ± 1.46 pg/ml vs. 104.89 ± 2.19 pg/ml vs. 106.11 ± 1.81 pg/ml , P = 0.012; 90 min: 79.96 ± 1.73 pg/ml vs. 141.73 ± 2.90 pg/ml vs. 139.06 ± 2.79 pg/ml; P < 0.001), and percentages of immotility sperm (45 min: 27.7 ± 2.7% vs. 41.7 ± 2.2% vs. 41.7 ± 2.5%; 90 min: 29.9 ± 3.3% vs. 58.9 ± 4.0% vs. 63.1 ± 4.0%; all P < 0.001) were lowest, and glutathione peroxidase (45 min: 60.50 ± 1.54 U/ml vs. 37.09 ± 1.77 U/ml vs. 28.18 ± 1.06 U/ml; 90 min: 44.61 ± 1.23 U/ml vs. 16.86 ± 0.93 U/ml vs. 29.94 ± 1.56 U/ml; all P < 0.001), percentages of head DNA (45 min: 83.2 ± 2.0% vs. 68.2 ± 2.5% vs. 38.8 ± 1.6%; 90 min: 80.3 ± 1.5% vs. 26.3 ± 1.3% vs. 26.9 ± 1.1%; all P < 0.001), percentages of sperm vitality (45 min: 89.5 ± 1.6% vs. 70.7 ± 3.1% vs. 57.7 ± 2.4%; 90 min: 80.8 ± 2.2% vs. 40.4 ± 4.0% vs. 34.7 ± 3.9%; all P < 0.001), and progressive sperm (45 min: 69.3 ± 2.7% vs. 55.8 ± 2.2% vs. 55.4 ± 2.5%; 90 min: 67.2 ± 3.3% vs. 38.2 ± 4.0% vs. 33.9 ± 4.0%; all P < 0.001) were highest in Wi-Fi plus 5 mmol/L trolox group at 45 and 90 min, respectively. Other parameters were not affected, while the sham group maintained the baseline.</p><p><b>Conclusion</b>This study found that 5 mmol/L trolox protected the Wi-Fi-exposed semen in vitro from the damage of electromagnetic radiation-induced oxidative stress.</p>

Adição de antioxidantes ao sêmen de carneiros e seus efeitos após a descongelação / Addition of antioxidants in ram semen and the effects after thawing

Objetivou-se avaliar o efeito da adição dos antioxidantes ácido ascórbico, melatonina e Trolox C, associados ao sêmen diluído de carneiros sobre o estresse oxidativo e o potencial fecundante após criopreservação. Foram coletados 10 ejaculados de 3 carneiros (n=30) e diluídos em Tris-Gema de ovo até a concentração final de 200x106 sptz/mL e, mantidos em banho maria a 32°C. Os antioxidantes foram adicionados da seguinte forma: controle (sem adição de antioxidantes); 100µM de melatonina (MEL) + 0,05% de ácido ascórbico (AA); 100µM de MEL + 90µL de Trolox C (TRO); 90µL de TRO + 0,05% de AA; e 100µM de MEL + 0,05%AA + 90µL de TRO. Depois, o sêmen foi resfriado em câmara fria a 5°C por duas horas, após esse período, envasado e lacrado em palhetas de 0,5mL, e então acondicionado sob vapor de nitrogênio liquido (N2L), a 8cm da lâmina líquida por 15 minutos, e depois imersos no N2L. As amostras foram analisadas quanto à motilidade espermática, integridade da membrana plasmática e da membrana acrossomal, atividade mitocondrial, teste de ligação e a quantificação do estresse oxidativo. As variáveis foram submetidas à análise de variância e medias comparadas pelo teste de Tukey a 5% de probabilidade. A motilidade (total e progressiva) foi maior (P<0,05) quando adicionado à associação MEL+AA+TRO (67% e 49,89%), MEL+AA (64,37% e 45,61%) e MEL+TRO (61,65% e 41,15%) comparado ao tratamento controle (55,52% e 36,54%) e TRO+AA (57,07% e 38,40%). A adição de MEL+AA+TRO ao sêmen diluído manteve (P<0,05) a integridade da membrana plasmática (30,75%) e acrossomal (84,53%) dos espermatozoides quando comparado ao tratamento controle (15,60 e 68,16%, respectivamente), além de ter promovido maior (P<0,05) atividade mitocondrial (96,43%) quando comparado aos demais tratamentos. O número de espermatozoides que apresentaram à capacidade de ligação a membrana perivitelina da gema de ovo foi maior (P<0,05) no sêmen tratado com as diferentes associações de antioxidante quando comparado ao controle, sendo a associação MEL+AA+TRO (178,36%) superior (P<0,05) aos demais tratamentos. Não houve diferença (P>0,05) entre os tratamentos quanto a quantidade de espécies reativas ao ácido tiobarbitúrico produzidos. Conclui-se que a adição de MEL+AA+TRO ao sêmen diluído de carneiros, nas doses avaliadas, melhora a qualidade espermática após descongelação.(AU)

Aimed to evaluate the effect of adding antioxidants as ascorbic acid, melatonin and Trolox C to diluted semen of ram with oxidative stress to potenciate fertilization after cryopreservation. Ten samples collected were diluted in Tris-egg yolk to a final concentration of 200x106 sperm/mL and kept in a water bath at 32°C. Antioxidants were added as follows: 100µM melatonin (MEL) +.05% ascorbic acid (AA); 100µM of MEL + 90µL of Trolox C (TRO); 90µL of TRO + 0.05% AA; and 100µM of MEL0.05% AA + 90µL of TRO. Semen was cooled in a cold chamber at 5°C for two hours and packaged, sealed in 0.5mL straws, packaged under liquid nitrogen vapor (N2L), 8cm of water depth for 15 minutes, and then immersed in N2L. Samples were assayed for motility, integrity of the plasma membrane and acrosomal membrane, mitochondrial activity, binding assay and oxidative stress spermatozoa. The variables were analyzed by ANOVA and means compared by Tukey test (P<0.05). Percentage of total and progressive motility was higher for sperm treated with MEL+AA+TRO (67% and 49.89%), MEL+AA (64.37% and 45.61%) and MEL+TRO (61.65% and 41.15%) compared with the other treatments (P<0.05). The integrity of the plasma membrane and acrosome was higher for all semen treated with antioxidant associations compared with control (P<0.05). Mitochondrial activity was higher in sperm treated with MEL+AA+TRO compared all treatments (P<0.05). The number of sperm binding to perivitelline membrane was higher for semen treated with antioxidant associations compared with control; also sperm treated with MEL+AA+TRO demonstrated higher effect of all (P<0.05). No difference was observed between the treatments by oxidative stress sperm (P>0.05). The addition of melatonin, ascorbic acid and Trolox C in diluted semen of ram improves sperm quality after thawing.(AU)

Guanidinoacetate alters antioxidant defenses and butyrylcholinesterase activity in the blood of rats

Deficiency of guanidinoacetate methyltransferase, the first described creatine biosynthesis defect, leads to depletion of creatine and phosphocreatine, and accumulation of guanidinoacetate (GAA) in brain and body fluids. The present study aimed to investigate the influence of GAA on the activities of antioxidant enzymes, as well as on thiobarbituric acid-reactive substances (TBARS) and butyrylcholinesterase (BuChE) activity in the blood of rats. We also evaluated the effect of trolox (6-hydr oxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), GSH (glutathione) and L-NAME (NG-nitro-L-arginine methyl ester) on the alterations elicited by GAA. Methods: The rats were randomly divided into 8 groups: (1) control; (2) GAA (10, 30, 50, 100 mM/kg); (3) trolox (1 mM/kg) + control; (4) trolox (1 mM/kg) + GAA (100 mM/kg); (5) GSH (1 mM/kg) + control; (6) GSH (1 mM/kg) + GAA (100 mM/kg); (7) L-NAME (1 mM/kg) + control; (8) L-NAME + GAA (100 mM/kg). After the addition of compounds, erythrocytes and plasma were pre-incubated at 37°C for 1h and tested immediately. Results: GAA enhanced the activities of catalase (CAT) and glutathione peroxidase (GSH-Px) in the erythrocytes and BuChE activity. In addition, GAA enhanced TBARS levels in the plasma. Trolox, GSH and L-NAME addition prevented the majority of alterations in oxidative stress parameters and the increase of BuChE activity that were caused by GAA. Data suggest that GAA alters antioxidant defenses and induces lipid peroxidation in the blood, as well altering BuChE activity. However, in the presence of trolox, GSH and L-NAME some of these alterations in oxidative stress and BuChE activity were prevented. Conclusions: Our findings lend support to a potential therapeutic strategy for this condition, which may include the use of appropriate antioxidants for ameliorating the damage caused by GAA...

Actividad antioxidante y antihiperglucemiante de la especie medicinal Oreocallis grandiflora (Lam.) R. Br., al sur del Ecuador / Antioxidant and antihyperglycemic activity of the medicinal specie Oreocallis grandiflora (Lam.) R. Br., in southern Ecuador

In this study we evaluated the antioxidant and antihyperglycemic activity in vitro of the extracts obtained with solvents: hexane, ethyl acetate and methanol, of the medicinal plant Oreocallis grandiflora (cucharillo), collected in the Saraguro indian community of the province Loja, southern Ecuador. The antioxidant activity was evaluated by the tests: DPPH, FOLIN-CIOCALTEU and beta-CLAMS, while the antihyperglycemic activity was determined by inhibition assay á-amylase and alpha-glucosidase. The samples were diluted to different concentrations and the reading was performed in a UV spectrophotometer, using as positive control á-tocopherol for DPPH and Folin-ciocalteu test, trolox for beta-CLAMS test, and Glucobay® for testing alpha-amylase and alpha-glucosidase.The results are expressed as IC50, these show that the methanol extract of Oreocallis grandiflora has inhibitory effect on alpha-amylase, the IC50 is 109 ug/ml, compared to 126 ug/ ml of Glucobay®. It also shows inhibitory effect on á-glucosidase, the IC50 is 3 ug/ml compared to 1316 ug/ml of Glucobay®. It also shows antioxidant activity, its IC50 is 15 ug/ml compared to 5 ug/ml of á-tocopherol.

En el presente trabajo se evaluó la actividad antioxidante y antihiperglucemiante in vitro de los extractos obtenidos con los solventes: hexano, acetato de etilo y metanol, de la planta medicinal Oreocallis grandiflora (cucharillo), recolectada en la comunidad indígena de Saraguro en la provincia de Loja, al sur del Ecuador. La actividad antioxidante fue evaluada a través de los ensayos: DPPH, FOLIN-CIOCALTEU y beta-CLAMS, mientras que la actividad antihiperglucemiante fue determinada por el ensayo de inhibición de alfa- amilasa y alfa-glucosidasa. El extracto metanólico de Oreocallis grandiflora presenta efecto inhibitorio sobre la enzima alfa-amilasa, su concentración inhibitoria (CI50) es de 109 ug/ml, frente a 126 ug/ml del control positivo Glucobay®. Además, muestra efecto inhibitorio sobre la enzima alfa-glucosidasa, su concentración inhibitoria (CI50) es de 3 ug/ml, frente a 1316 ug/ml del Glucobay®. Muestra también actividad antioxidante, su concentración inhibitoria (CI50) es de 15 ug/ml, frente a 5 ug/ml del alfa-tocoferol.

ANTIOXIDANTES E BETA-GLUCANAS EM BARRAS DE CEREAIS COM Agaricus brasiliensis / ANTIOXIDANTS AND BETA-GLUCAN IN CEREAL BARS WITH Agaricus brasiliensis

O objetivo deste trabalho foi avaliar a capacidade antioxidante, a concentração de compostos fenólicos e de beta-glucanas em barras de cereais com Agaricus brasiliensis. As barras de cereais foram elaboradas por delineamento para mistura simplex-centroide para três variáveis: aveia, gergelim e trigo fermentado com A. brasiliensis. Os teores de ß-glucanas nas amostras variaram de 1,30 a 3,82 g.100 g-1 e os compostos fenólicos de 67,45 a 81,96 mg EAG.100 g-1, constatando-se capacidade antioxidante na faixa de 29,47 a 40,17 mg CAET.100 g-1. A adição de micélio de Agaricus brasiliensis em produtos alimentícios pode torná-los mais saudáveis, devido às propriedades nutritivas e compostos bioativos desse micro-organismo.

Plasma Total Antioxidant Capacity (TAC) in Obese Malaysian Subjects

Introduction: There is a pressing need to better understand the complex biochemical pathways that lead to the pathogenesis of obesity. Increased oxidative stress and decreased antioxidant capacity have been identified to be associated with obesity. Therefore, the objectives of this study were to determine the plasma total antioxidant capacity (TAC) levels of Malaysian subjects and to evaluate its potential association with obesity and related anthropometric measurements. Methods: Plasma TAC of 362 multi-ethnic Malaysian subjects from the Kampar Health Clinic (138 males, 224 females; 124 ethnic Malays, 152 Chinese, 86 Indians; 192 non-obese, 170 obese) was measured using Trolox equivalent antioxidant capacity (TEAC) 96-well plate assay. Results: Plasma TAC was significantly lower in obese subjects (M ± SE = 292 ± 10.4 mol/L) compared to non-obese subjects (397 ± 8.58 mol/L), whereas it was significantly higher in males and those in the 21-30 age group. Those with salty food preference and practising a strict vegetarian diet also had significantly higher plasma TAC. However, no association was found for other dietary habits (coffee intake) and lifestyle factors (physical activity, smoking). Plasma TAC was also significantly negatively correlated with diastolic blood pressure, waist and hip circumferences, weight, body mass index, total body fat, % subcutaneous fat, visceral fat level, resting metabolism and % skeletal muscle. Conclusion: Plasma TAC was found to be associated with obesity, strict vegetarian practice, salty food preference and all obesity anthropometric indicators, except systolic blood pressure and pulse rate. Obese people have decreased plasma TAC indicating a compromised systemic antioxidant defence and increased oxidative stress.

Adição de piruvato de sódio e trolox ao diluidor utilizado para congelação de sêmen de garanhões férteis e subférteis / Effect of pyruvate and trolox added to the extender used for freezing fertile and subfertile stallion semen

O objetivo deste trabalho foi avaliar o efeito do piruvato e trolox (forma solúvel da vitamina E) sobre a qualidade espermática pós-descongelamento. Assim, com o intuito de proteger as células espermáticas dos efeitos deletérios da criopreservação,foram considerados os seguintes tratamentos: T1 (Controle)= INRA82-HEPES sem antioxidantes; T2= INRA82-HEPES + 2mM de piruvato e T3= INRA82-HEPES + 120mM de trolox. As amostras de sêmen descongeladas foram avaliadas quanto à motilidade total (MT) e progressiva (MP), a integridades de membrana plasmática e acrossômica, integridade do DNA, à estabilidade de membrana e ao potencial de membrana mitocondrial (Δψm). A adiηγo de piruvato proporcionou resultados superiores (P<0,05) àqueles obtidos com trolox na motilidade espermática total (9,17 e 14,5 por cento, respectivamente). A adição de piruvato incrementa a motilidade espermática (18,92 e 19,0 por cento, respectivamente) em garanhões férteis e subférteis submetidos à congelação.

The objective of this research was to evaluate the effect of pyruvate and trolox on the thawed sperm quality. For freezing, antioxidants were added to INRA 82-HEPES extender to protect sperm from the deleterious effects of oxidative stress, according to the treatments: T1= INRA82-HEPES without antioxidants; T2= INRA82-HEPES + 2mM of pyruvate and T3= INRA82-HEPES + 120 mM de trolox. The thawed semen samples were evaluated according to the total (MT) and progressive (MP) motility, integrity of plasma and acrossomal membrane, DNA integrity, membrane stability and mitochondrial membrane potential (Δψm). It was observed that the addition of pyruvate resulted in a significantly higher total sperm motility (P<0.05) to those obtained with trolox (9.17 and 14.5 percent, respectively). It can be concluded that the addition of pyruvate improves sperm motility (18.92 and 19.0 percent, respectively) in samples from fertile and sub-fertile stallions submitted to freezing.

Measurement of antioxidant activity with trifluoperazine dihydrochloride radical cation

A novel, rapid and cost-effective trifluoperazine dihydrochloride (TFPH) decolorization assay is described for the screening of antioxidant activity. A chromogenic reaction between TFPH and potassium persulfate at low pH produces an orange-red radical cation with maximum absorption at 502 nm in its first-order derivative spectrum. TFPH was dissolved in distilled water to give a 100 mM solution. The TFPH radical cation solution was made by reacting 0.5 mL of the solution with K2S2O8 (final concentration: 0.1 mM) and diluting to 100 mL with 4 M H2SO4 solution. A linear inhibition of color production was observed with linearly increasing amounts of antioxidants, with correlation coefficients (R²) ranging from 0.999 to 0.983. The antioxidant capacity of standard solutions of an antioxidant was evaluated by comparing with the inhibition curve using Trolox as the standard. Comparison of antioxidant capacity determined with this newly developed TFPH assay and with the well-known 2,2'-azinobis-[3-ethylbenzthiazoline-6-sulfonic acid] (ABTS)-persulfate decolorization assay indicated the efficacy and sensitivity of the procedure. The proposed assay is less expensive (costs about US$4 per 100 assays) and requires only 20 min for preparation of radical cation solution in comparison with ABTS assay, in which almost 12-16 h are required for preparation of a stable ABTS radical cation solution. The present assay has the advantage over ABTS assay that it can be used to measure the antioxidant activity of the samples, which are naturally found at a pH as low as 1, because the radical cation itself has been stabilized at low pH.