Melatonina, lactancia materna y sueño: revisión del tema / Melatonin, breastfeeding and sleep: topic review

Se revisa en el binomio madre-recién nacidos o/y lactantes, los diferentes ritmos circadianos, especialmente del sueño, la secreción de melatonina y las características de la leche materna. Se aconseja manejo para evitar la cronodisrupción

It is reviewed in the binomial mother-newborns or/and infants, the different circadian rhythms, especially sleep, melatonin secretion and the characteristics of breast milk. Handling is advised to avoid chrono disruption

History of scurvy and use of vitamin C in critical illness: A narrative review.

In 1747, an important milestone in the history of clinical research was set, as the Scottish surgeon James Lind conducted the first randomized controlled trial. Lind was interested in scurvy, a severe vitamin C deficiency which caused the death of thousands of British seamen. He found that a dietary intervention with oranges and lemons, which are rich in vitamin C by nature, was effective to recover from scurvy. Because of its antioxidative properties and involvement in many biochemical processes, the essential micronutrient vitamin C plays a key role in the human biology. Moreover, the use of vitamin C in critical illness-a condition also resulting in death of thousands in the 21st century-has gained increasing interest, as it may restore vascular responsiveness to vasoactive agents, ameliorate microcirculatory blood flow, preserve endothelial barriers, augment bacterial defense, and prevent apoptosis. Because of its redox potential and powerful antioxidant capacity, vitamin C represents an inexpensive and safe antioxidant, with the potential to modify the inflammatory cascade and improve clinical outcomes of critically ill patients. This narrative review aims to update and provide an overview on the role of vitamin C in the human biology and in critically ill patients, and to summarize current evidence on the use of vitamin C in diverse populations of critically ill patients, in specific focusing on patients with sepsis and coronavirus disease 2019.

Protection of mice against carbon tetrachloride-induced acute liver injury by endogenous and exogenous estrogens.

Gender is a crucial factor determining susceptibility to drug-induced liver injury (DILI) in humans and experimental animals. However, no general concept of sex differences in DILI has been established, as metabolic events specific to one DILI model are difficult to apply to other DILI models. Herein, we examined sex differences in carbon tetrachloride (CCl4)-induced hepatotoxicity, a widely employed DILI model. Male and female CD-1 mice were intraperitoneally administered CCl4. Additionally, some male mice were administered genistein or another isoflavone to evaluate the effects of exogenous estrogens. Dose-dependent alanine aminotransferase leakage was observed at a CCl4 range of 0.5-10 mmol/kg, with male-dominant sex differences mainly observed at lower doses. No sex differences in hepatic glutathione levels or thiobarbituric acid-reactive substance formation were detected. CCl4 induced hepatic inflammatory genes, interleukin (IL)-6 and tumor necrosis factor (TNF)-α, predominantly in female mice, which might be involved in DILI resistance, observed in female mice. Treatment of male mice with phytoestrogens, especially genistein, attenuated CCl4-induced hepatotoxicity. Moreover, genistein inhibited IL-6 and TNF-α expression, suggesting possible hepatoprotection via immunosuppression. In conclusion, female mice are resistant to CCl4-induced hepatotoxicity, and male mice were afforded protection by genistein, probably via mechanisms based on anti-estrogenic, antioxidant and/or anti-inflammatory effects.

Bioactivity-guided isolation of the major anthocyanin from Lycium ruthenicum Murr. fruit and its antioxidant activity and neuroprotective effects in vitro and in vivo.

Lycium ruthenicum Murr. fruit (LRF) is an edible berry known for its rich anthocyanin content. Our previous study has shown that LRF-derived anthocyanins have neuroprotective effects in rats, which may be due to their effective antioxidant activity. Therefore, this study performed online HPLC-DPPH screening as a bioactivity-guided method for the preparative separation of anthocyanins from LRF. Finally, the main fraction was isolated and identified as petunidin-3,5-O-diglucoside (Pn3G5G). Pn3G5G exhibited strong antioxidant capacity during DPPH and ABTS free radical scavenge assays. Furthermore, Pn3G5G exhibited protective effects on Nε-carboxymethyllysine (CML)-treated Neuro-2a cells by enhancing cell viability in a dose-dependent manner. CML-induced apoptosis was also reduced by Pn3G5G potentially by suppressing oxidative stress and inflammation. More importantly, Pn3G5G significantly improved cognitive impairment, neuroinflammation and neuronal apoptosis in D-galactose-induced aging mice. The result suggests the development of Pn3G5G as a healthcare product or a potent dietary supplement with antioxidant and neuroprotective effects.

The role of Acanthamoeba castellanii (T4 genotype) antioxidant enzymes in parasite survival under H2O2-induced oxidative stress.

Acanthamoeba castellanii (A. castellanii) is an important opportunistic parasite. Induction of oxidative stress by the host immune system is one of the most important defense strategies against parasites. Hence, parasites partly deal with oxidative stress by different mechanisms. Identifying resistance mechanisms of A. castellanii parasites against oxidative stress is important to achieve a new therapeutic approach. Thus, this study aimed to understand the resistance mechanisms of A. castellanii, against oxidative stress. Trophozoites of A. castellanii were treated with different concentrations of H2O2. The half maximal inhibitory concentration (IC50) of H2O2 was determined using the MTT assay. The induction of oxidative stress was confirmed by flow cytometer. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) were determined. The gene expression levels of CAT and SOD were measured by qRT-PCR. Furthermore, 3-amino-1:2:4-triazole (3-AT) and potassium cyanide (KCN) were used as specific inhibitors of CAT and SOD, respectively. Cell cycle assay and the apoptosis were evaluated by flow cytometer. The activities of SOD, CAT, GR, and GPx, showed an increase in oxidative stress. The cell cycle analysis revealed that most of the cellular population was in G0 and G1 phases. The apoptosis increased in oxidative stress conditions. Moreover, the apoptosis significantly increased after the specific inhibition of CAT and SOD under oxidative stress. The gene expression levels of CAT and SOD significantly increased under oxidative stress. A. castellanii can resist the host immune system through various mechanisms, including evoking its antioxidant enzymes. Therefore, by reducing or inhibiting the activity of the parasite's antioxidant enzymes such as SOD and CAT, it is possible to cope with A. castellanii.

Effect of açai supplementation (Euterpe Oleracea Mart) associated with exercise in animals and human: a scoping review / Efeitos da suplementação com açaí (Euterpe Oleracea Mart) associada ao exercício físico em animais e humanos: revisão de escopo

ABSTRACT Objective This scoping review aimed to map evidence on açai supplementation combined with exercise in animal and/or human experimental studies. Methods The search considered six electronic databases and screening of relevant references. The selection process and data extraction were performed by two independent authors. The study characteristics, and AS (e.g., form, intervention time, amount ingested) and exercise (e.g., types, intensity, and duration) strategies were summarized, as well as their reported results. Results From an initial total of 342 studies identified; 11 (5 with animal and 6 with human models) were eligible. In animals, açai supplementation and exercise led to benefits in exercise tolerance and improvements in several hemodynamic parameters, as well as significant improvements in liver markers and glucose metabolism. In humans, açai supplementation indicated positive results in increasing exhaustion time to 90% of VO2max and increasing intensity at the anaerobic threshold. Conclusion We conclude that future research involving animals and humans should examine açai supplementation and exercise with (a) obesity models to test the effect of adiponectin on body composition with analysis of histological and histochemical parameters; (b) eccentric injury protocols with the incorporation of muscle quality variables to assess recovery; (c) chronic açai supplementation and strength training; (d) comparison of different forms of açai supplementation in exercise protocols.

RESUMO Objetivo Esta revisão de escopo teve como objetivo mapear evidências sobre a suplementação com açaí combinada com exercícios físicos em estudos experimentais em animais e / ou humanos. Métodos A busca considerou seis bases de dados eletrônicas além da triagem de referências relevantes. O processo de seleção e extração de dados foi realizado por dois autores independentes. As características do estudo, estratégias de suplementação de açaí (forma, tempo de intervenção, e quantidade ingerida) e exercícios (tipos, intensidade e duração), seus resultados foram resumidos. Resultados Um total de 342 estudos foram inicialmente alcançados e somente 11 foram elegíveis (5 com animais e 6 com humanos). Em animais, a suplementação de açaí e os exercícios indicaram benefícios na tolerância ao exercício e melhorias em vários parâmetros hemodinâmicos, bem como melhorias significativas nos marcadores hepáticos e no metabolismo da glicose. Em humanos, a suplementação de açaí indicou resultados positivos no aumento do tempo de exaustão para 90% do VO2máx e no aumento da intensidade correspondente ao limiar anaeróbio. Conclusão Concluiu-se que pesquisas futuras envolvendo animais e humanos devem examinar a suplementação de açaí e exercícios com (a) modelos de obesidade para testar o efeito da adiponectina na composição corporal por meio de parâmetros histológicos e histoquímicos (b) protocolos de dano muscular excêntrico com incorporação de variáveis de qualidade muscular para avaliação da recuperação; (c) suplementação crônica de açaí e treinamento de força; (d) comparação das diferentes formas de suplementação de açaí em protocolos de exercícios.

Glucose metabolism and pyruvate carboxylase enhance glutathione synthesis and restrict oxidative stress in pancreatic islets.

Glucose metabolism modulates the islet ß cell responses to diabetogenic stress, including inflammation. Here, we probed the metabolic mechanisms that underlie the protective effect of glucose in inflammation by interrogating the metabolite profiles of primary islets from human donors and identified de novo glutathione synthesis as a prominent glucose-driven pro-survival pathway. We find that pyruvate carboxylase is required for glutathione synthesis in islets and promotes their antioxidant capacity to counter inflammation and nitrosative stress. Loss- and gain-of-function studies indicate that pyruvate carboxylase is necessary and sufficient to mediate the metabolic input from glucose into glutathione synthesis and the oxidative stress response. Altered redox metabolism and cellular capacity to replenish glutathione pools are relevant in multiple pathologies beyond obesity and diabetes. Our findings reveal a direct interplay between glucose metabolism and glutathione biosynthesis via pyruvate carboxylase. This metabolic axis may also have implications in other settings where sustaining glutathione is essential.

Effects of Boron and NaCl on Antioxidant Defence Mechanisms in Duckweeds (Spirodela polyrhiza L.).

<b>Background and Objective:</b> Boron is one of the principal elements required for plant's growth but extreme amounts of boron are toxic to humans, animals and plants. This study aimed to utilized growth rates, dry biomass and antioxidant enzyme activities to evaluate the potential of <i>Spirodela polyrhiza</i> L., in which <i>S. polyrhiza</i> produced for 120 hrs in water containing control, 10, 20, 40 and 80 mg L¹ of Boron and sodium chloride (NaCl) concentrations changing from 0-50 mM. <b>Materials and Methods:</b> In this study, we have done with <i>S. polyrhiza</i>, Boron and NaCl applications were continued for 120 hrs. After 120 hrs, the plants were harvested, cleaned with pure water, frozen at fluid nitrogen and stored at -80°C until further usage for enzymes activity. To determine the amount of Boron in <i>S. polyrhiza</i>, the samples were dried at 70 and then measured with Thermo ICP-MS. <b>Results:</b> The results indicated that the Boron accumulation capacity of <i>S. polyrhiza</i> diminished with accelerating salinity. <i>Spirodela polyrhiza</i> may have utilized various mechanisms to collecting Boron in high and low salt concentrations. As a conclusion of the study, it was stated that the growth rate of <i>S. polyrhiza</i> and total chlorophyll synthesis were considerably obstructed when NaCl amounts reached 50 mM. <b>Conclusion:</b> Our results indicate that CAT, APX and SOD can serve as substantial biomarkers in Boron-rich habitats. This <i>S. polyrhiza</i> is a very beneficial exemplary plant for phytoremediation advancement of contaminated wastewater with low Boron content.

HPLC-Analysis, Biological Activities and Characterization of Action Mode of Saudi Marrubium vulgare against Foodborne Diseases Bacteria.

The present study aims to evaluate the chemical composition, metabolites secondary and pharmacology activities of methanolic extract of Marrubium vulgare collected from King Saudi Arabia. Moreover, the primary mode of action of the tested extract was studied here for the first time against E. coli and L. monocytogenes. HPLC analysis shows that the major components in the tested extract are luteolin-7-O-d-glucoside, ferulic acid and premarrubiin. Obtained data demonstrated that the investigated extract was richer in phenol (26.8 ± 0.01 mg/GAE g) than in flavonoids (0.61 ± 0.05 mg EC/mL). In addition, the methanolic extract showed an important antioxidant capacity against the DPPH (IC50 = 35 ± 0.01 µg/mL) and ABTS (IC50 = 25 ± 0.2 µg/mL) radical scavenging and a strong inhibition of acetylcholinesterase enzyme with an IC50 value corresponding to 0.4 mg/mL. The antibacterial activity demonstrated that the evaluated extract had significant activity against both Gram-positive and Gram-negative bacteria. The effect of time on cell integrity on E. coli and L. monocytogenes determined by time-kill and bacteriolysis tests showed that the M. vulgare extract reduced the viability of both strains after 8 and 10 h and had a bacteriolytic effect against two different categories of bacteria, Gram-positive and negative, which are not of the same potency. Based on obtained data, it can be concluded that Saudi M. vulgare has a high pharmacological importance and can be used in preparation of food or drugs.

Schisandra chinensis polysaccharides prevent cardiac hypertrophy by dissociating thioredoxin-interacting protein/thioredoxin-1 complex and inhibiting oxidative stress.

Cardiac hypertrophy is a current, major, global health challenge. Oxidative stress is an important mechanism that contributes to the pathogenesis of cardiac hypertrophy. Schisandra chinensis polysaccharides (SCP), the primary active constituent in Schisandra chinensis, have antioxidative properties. Here, we investigated the role played by SCP in a cardiac hypertrophy model mouse induced by transverse aortic constriction (TAC). We found that SCP treatment improved cardiac function by inhibiting myocardial hypertrophy and oxidative stress. Angiotensin II was used to induce cardiomyocyte hypertrophy and oxidative stress in vitro. We discovered that the antioxidant effects of SCP were mediated through the regulation of the thioredoxin-interacting protein (TXNIP)/Thioredoxin-1 (Trx-1) pathway. Using molecular docking, we found that SCP binds to Arg207, Ser169, Lys166, Lys286 and Ser285 in TXNIP through hydrogen bonds. TXNIP is an endogenous inhibitor of Trx-1, and the binding SCP with TXNIP may restrict or interfere with the binding between TXNIP and Trx-1, resulting in Trx-1 activation. In conclusion, our findings demonstrated that the potential use of SCP as a TXNIP inhibitor to attenuate oxidative stress, suggesting that TXNIP might represent a potential therapeutic target for the treatment of cardiac hypertrophy.

Multifunctional compounds in the extract from mature seeds of Vicia faba var. minor: Phytochemical profiling, antioxidant activity and cellular safety in human selected blood cells in in vitro trials.

BACKGROUND: The field bean (Vicia faba) is a valuable fodder plant of the Fabaceae family, grown as a main crop for its seed yield. Its phytochemical profile is characterized by the presence of a range of compounds with various biological activities. PURPOSE: The present study investigates the phytochemical profile of the extract from mature seeds of Vicia faba var. minor and examines its impact on preventing oxidative damage to various lipids, protein and DNA molecules in vitro. METHODS: Human plasma was treated with H2O2/Fe (an OH. donor) to induce oxidative damage to lipids and proteins, and the plant extract was then added. As oxidative stress may influence the biological activity of plasma, e.g. coagulation, and influence cardiovascular disease, the study also examined the effect of the plant extract on coagulation and monoamine oxidase activity (MAO, EC 1.4.3.4). RESULTS: The tested extract exerted a protective effect on plasma lipids and proteins treated with H2O2/Fe. However, while it appears to effectively protect the DNA in peripheral blood mononuclear cells from oxidative damage, it did not induce changes in the coagulation process, and significantly reduced MAO activity when applied at 1, 5, and 10 µg/mL. It is possible that the observed antioxidant potential may be due to the complex chemical composition of the extract: the phytochemical profile demonstrated a range of phenolic compounds, including catechins. CONCLUSION: Our findings indicate that extract from mature seeds of V. faba var. minor may be a promising source of antioxidants in multiple applications, including diseases associated with oxidative stress; however, more studies based on in vitro and in vivo models are needed to determine its biological properties.

Impact of Harvest Conditions and Host Tree Species on Chemical Composition and Antioxidant Activity of Extracts from Viscum album L.

The content of plant secondary metabolites is not stable, and factors such as the region/location effect and seasonal variations have an impact on their chemical composition, especially in parasitic plants. Research in this area is an important step in the development of quality parameter standards of medicinal plants and their finished products. The effects of the time and place of harvest and the host tree species on the chemical composition and antioxidant activity of mistletoe extracts were investigated. Statistical tools were used to evaluate the results of the spectrophotometric and LC-ESI-MS/MS studies of the phenolic composition and antioxidant activity. The investigations indicate that the qualitative and quantitative composition, influencing the biological activity of mistletoe extracts, largely depends on the origin of the plant. The mistletoe extracts exhibited a rich phenol profile and high antioxidant activity. The chemometric analysis indicated that mistletoe collected from conifers (Viscum abietis and Viscum austriacum) had the most advantageous chemical composition and antioxidant activity. Moreover, the chemical profile and biological activity of the plant material were closely related to the climatic conditions and location of the harvested plant. Higher levels of phenolic compounds and high antioxidant activity were found in extracts obtained from plant material collected in cold weather with the presence of snow and less sunshine (autumn-winter period).

Inflammatory, antioxidant and glycemic status to different mode of high-intensity training in type 2 diabetes mellitus.

BACKGROUND: Exercise has traditionally been used and prescribed as an effective and suitable way to treat type 2 diabetics Mellitus (T2DM). In this regard, we compared inflammatory, antioxidant, and glycemic status to different kinds of high-intensity interval training (strength training, HIIT, and HIIT + ST) in patients with T2DM. METHODS AND RESULTS: Fifty-nine T2DM patients (age = 45-60 yrs) were randomly divided to strength training (ST) (n = 15), high intensity interval training (HIIT) (n = 16), HIIT + ST (n = 15) or served as control (CON) (n = 13) groups. Experimental groups performed three training sessions/week for 12 weeks. Inflammatory, antioxidant, glycemic factors, and anthropometric parameters were evaluated at baseline and after the 12 weeks of interventions. Training HIIT groups significantly improved antioxidant factors, lipid profile, and glycemic parameters (P ≤ 0.05). Interleukin 6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor-α (TNF-α) significantly decreased in the three training groups. As a result of training, the overall inflammatory and antioxidant status were improved considerably in all three training groups compared to the CON group (P ≤ 0.05). In addition, there were significant differences in CRP at the follow-up values between ST and CON groups (P ≤ 0.05). Exercise time and TC were significantly improved in HIIT than in the CON group (P ≤ 0.05). The results showed a significant difference between the HIIT + ST group and the CON group in VO2peak (P ≤ 0.05). CONCLUSIONS: Our results showed improvement in inflammatory factors, antioxidants, and glycemic parameters in all training groups regardless of their type. However, for more benefits in T2DM patients, combination exercises can be suggested.

Protective role of taurine against oxidative stress (Review).

Taurine is a fundamental mediator of homeostasis that exerts multiple roles to confer protection against oxidant stress. The development of hypertension, muscle/neuro­â€‹associated disorders, hepatic cirrhosis, cardiac dysfunction and ischemia/reperfusion are examples of some injuries that are linked with oxidative stress. The present review gives a comprehensive description of all the underlying mechanisms of taurine, with the aim to explain its anti­oxidant actions. Taurine is regarded as a cytoprotective molecule due to its ability to sustain normal electron transport chain, maintain glutathione stores, upregulate anti­oxidant responses, increase membrane stability, eliminate inflammation and prevent calcium accumulation. In parallel, the synergistic effect of taurine with other potential therapeutic modalities in multiple disorders are highlighted. Apart from the results derived from research findings, the current review bridges the gap between bench and bedside, providing mechanistic insights into the biological activity of taurine that supports its potential therapeutic efficacy in clinic. In the future, further clinical studies are required to support the ameliorative effect of taurine against oxidative stress.

The oxidoreductase PYROXD1 uses NAD(P)+ as an antioxidant to sustain tRNA ligase activity in pre-tRNA splicing and unfolded protein response.

The tRNA ligase complex (tRNA-LC) splices precursor tRNAs (pre-tRNA), and Xbp1-mRNA during the unfolded protein response (UPR). In aerobic conditions, a cysteine residue bound to two metal ions in its ancient, catalytic subunit RTCB could make the tRNA-LC susceptible to oxidative inactivation. Here, we confirm this hypothesis and reveal a co-evolutionary association between the tRNA-LC and PYROXD1, a conserved and essential oxidoreductase. We reveal that PYROXD1 preserves the activity of the mammalian tRNA-LC in pre-tRNA splicing and UPR. PYROXD1 binds the tRNA-LC in the presence of NAD(P)H and converts RTCB-bound NAD(P)H into NAD(P)+, a typical oxidative co-enzyme. However, NAD(P)+ here acts as an antioxidant and protects the tRNA-LC from oxidative inactivation, which is dependent on copper ions. Genetic variants of PYROXD1 that cause human myopathies only partially support tRNA-LC activity. Thus, we establish the tRNA-LC as an oxidation-sensitive metalloenzyme, safeguarded by the flavoprotein PYROXD1 through an unexpected redox mechanism.

The role of endogenous antioxidants in male animal fertility.

Mammalian semen is a physiological fluid composed of a cellular fraction (spermatozoa), and a liquid fraction (seminal plasma). Once delivered to the female genital tract, spermatozoa should be able to capacitate; a process which involves a plethora of biochemical and physiological changes required to fertilize the oocyte. Sperm production (spermatogenesis) occurs in the testes, whereby pluripotent spermatogonia differentiate to form the most morphologically specialized cells in the body. Further maturation of spermatozoa occurs in the epididymis, where they are stored prior to ejaculation. During this whole process, spermatozoa are exposed to different environments and cellular processes which may expose them to substantial levels of oxidative stress. To avoid damage associated with the unchecked production of reactive oxygen species (ROS), both spermatozoa, and the parts of the male genital tract in which they reside, are furnished with a suite of antioxidant molecules which are able to provide protection to these cells, thereby increasing their chance of being able to fertilize the oocyte and deliver an intact paternal genome to the future offspring. However, there are a host of reasons why these antioxidant systems may fail, including nutritional deficiencies, genetics, and disease states, and in these situations, a reduction or abolition of fertilizing capacity may result. This review paper focuses on the endogenous antioxidant defences available to spermatozoa during spermatogenesis and sperm maturation, the site of their production and their physiological role. Furthermore, we revised the causes and effects of antioxidant deficiencies (congenital or acquired during the animal's adulthood) on reproductive function in different animal species.

Triterpenes and Phenolic Compounds from the Fungus Fuscoporia torulosa: Isolation, Structure Determination and Biological Activity.

Investigation of the methanol extract of the poroid fungus Fuscoporia torulosa resulted in the isolation of a novel triterpene, fuscoporic acid (1), together with inoscavin A and its previously undescribed Z isomer (2 and 3), 3,4-dihydroxy-benzaldehide (4), osmundacetone (5), senexdiolic acid (6), natalic acid (7), and ergosta-7,22-diene-3-one (8). The structures of fungal compounds were determined on the basis of NMR and MS spectroscopic analyses, as well as molecular modeling studies. Compounds 1, 6-8 were examined for their antibacterial properties on resistant clinical isolates, and cytotoxic activity on human colon adenocarcinoma cell lines. Compound 8 was effective against Colo 205 (IC50 11.65 ± 1.67 µM), Colo 320 (IC50 8.43 ± 1.1 µM) and MRC-5 (IC50 7.92 ± 1.42 µM) cell lines. Potentially synergistic relationship was investigated between 8 and doxorubicin, which revealed a synergism between the examined compounds with a combination index (CI) at the 50% growth inhibition dose (ED50) of 0.521 ± 0.15. Several compounds (1 and 6-8) were tested for P-glycoprotein modulatory effect in Colo 320 resistant cancer cells, but none of the compounds proved to be effective in this assay. Fungal metabolites 2-5 were evaluated for their antioxidant activity using the oxygen radical absorbance capacity (ORAC) and DPPH assays. Compounds 4 and 5 were found to have a considerable antioxidant effect with EC50 0.25 ± 0.01 (DPPH) and 12.20 ± 0.92 mmol TE/g (ORAC). The current article provides valuable information on both the chemical and pharmacological profiles of Fuscoporia torulosa, paving the way for future studies with this species.

Kushenol C Prevents Tert-Butyl Hydroperoxide and Acetaminophen-Induced Liver Injury.

Sophora flavescens, also known as Kushen, has traditionally been used as a herbal medicine. In the present study we evaluated the ameliorative effects of kushenol C (KC) from S. flavescens against tBHP (tert-Butyl hydroperoxide)-induced oxidative stress in hepatocellular carcinoma (HEPG2) cells and acetaminophen (APAP)-induced hepatotoxicity in mice. KC pretreatment protected the HEPG2 cells against oxidative stress by reducing cell death, apoptosis and reactive oxygen species (ROS) generation. KC pretreatment also upregulated pro-caspase 3 and GSH (glutathione) as well as expression of 8-Oxoguanine DNA Glycosylase (OGG1) in the HEPG2 cells. The mechanism of action was partly related by KC's activation of Akt (Protein kinase B (PKB)) and Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) in the HepG2 cells. In in vivo investigations, coadministration of mice with KC and APAP significantly attenuated APAP-induced hepatotoxicity and liver damage, as the serum enzymatic activity of aspartate aminotransferase and alanine aminotransferase, as well as liver lipid peroxidation and cleaved caspase 3 expression, were reduced in APAP-treated mice. Coadministration with KC also up-regulated antioxidant enzyme expression and prevented the production of proinflammatory mediators in APAP-treated mice. Taken together, these results showed that KC treatment has potential as a therapeutic agent against liver injury through the suppression of oxidative stress.

The possible role of catalase in innate immunity and diminution of cellular oxidative stress: Insights into its molecular characteristics, antioxidant activity, DNA protection, and transcriptional regulation in response to immune stimuli in yellowtail clownfish (Amphiprion clarkii).

Catalase, a key enzyme in the antioxidant defense grid of organisms, scavenges free radicals to curtail their harmful effects on the host, supporting proper immune function. Herein, we report the identification and characterization of a catalase homolog from Amphiprion clarkii (ClCat), followed by its functional characterization. An open reading frame was identified in the cDNA sequence of ClCat at 1581 bp, which encodes a protein of 527 amino acids (aa) with a molecular mass of 60 kDa. In silico analyses of ClCat revealed characteristic features of the catalase family and a lack of a signal peptide. Multiple sequence alignment of ClCat indicated the conservation of functionally important residues among its homologs. According to phylogenetic analysis, ClCat was of vertebrate origin, positioned within the teleost clade. During native conditions, ClCat mRNA was highly expressed in blood, followed by the liver and kidney. Moreover, significant changes in ClCat transcription were observed after stimulation with LPS, poly I:C, and Vibrio harveyi, in a time-dependent manner. Recombinant ClCat (rClCat) was characterized, and its peroxidase activity was determined. Furthermore, the optimum temperature and pH for rClCat were determined to be 30-40 °C and pH 7, respectively. Oxidative stress tolerance and chromatin condensation assays indicated enhanced cell survival and reduced apoptosis, resulting from reactive oxygen species scavenging by rClCat. The DNA-protective function of rClCat was further confirmed via a metal-catalyzed oxidation assay. Taken together, our findings propose that rClCat plays an essential role in maintaining cellular oxidative homeostasis and host immune protection.

Effects of seleno-Sesbania canabina galactomannan on anti-oxidative and immune function of macrophage.

Seleno-polysaccharides have become a major topic for research owing to their high anti-oxidative capacity and immune-enhancing activities. In this study, galactomannan (GM) was isolated from Sesbania cannabina, and next modified using HNO3-Na2SeO3 method to obtain six varieties of seleno-galactomannans (SeGMs). FT-IR and GPC results showed the changes in chemical structure of SeGMs, indicating successful combination of selenium and GM. By measuring superoxide dismutase and malondialdehyde, the SeGMs showed a stronger protective effect against H2O2-induced oxidative damage in vitro than unmodified GM using macrophage RAW264.7 cell as a model, and the effect of SeGMs-14 was prominent. However, the selenylation modification did not show any obvious effect on the immunomodulatory activity of GM, as determined by the index of tumor necrosis factor-α, interleukin-6, and interleukin-1ß. Overall, the prepared SeGMs from galactomannan could potentially serve as a dietary supplement of Se or an organic antioxidant.