Energy management and mitochondrial dynamics in cerebral cortex during endotoxemia.

Mitochondria play an essential role in inflammatory processes such as sepsis or endotoxemia, contributing to organ-cellular redox metabolism, emerging as the energy hub of the cell, and as an important center of action of second messengers. In this work, we aimed to elucidate the energy state, redox balance, and mitochondrial remodeling status in cerebral cortex in an experimental model of endotoxemia. Female Sprague-Dawley rats were subjected to a single dose of LPS (ip 8 mg kg-1 body weight) for 6 h. State 3 O2 consumption was observed increased, ATP production and P/O ratio were observed decreased, probably indicating an inefficient oxidative phosphorylation process. O2- production and both systemic and tissue NO markers were observed increased in treated animals. The existence of nitrated proteins suggests an alteration in the local redox balance and possible harmful effects over energetic processes. Increases in PGC-1α and mtTFA expression, and in OPA-1 expression, suggest an increase in de novo formation of mitochondria and fusion of pre-existing mitochondria. The observed elongation of mitochondria correlates with the occurrence of mild mitochondrial dysfunction and increased levels of systemic NO. Our work presents novel results that contribute to unravel the mechanism by which the triad endotoxemia-redox homeostasis-energy management interact in the cerebral cortex, leading to propose a relevant mechanism for future developing therapeutics with the aim of preserving this organ from inflammatory and oxidative damage.

Cryoprotective effect of sericin supplementation in freezing and thawing media on the outcome of cryopreservation in human sperm.

The destructive effects of sperm cryopreservation result in decreased sperm parameters and their fertilizing ability. Antioxidants supplementation can potentially improve cryopreservation outcomes. In this study, we tried to investigate the effects of sericin supplementation in freezing and thawing media on frozen-thawed human sperm motility, morphology, viability, and DNA fragmentation. In experiment 1, semen samples were collected from 30 healthy fertile men and were cryopreserved in the presence of freezing medium supplemented with different concentrations of sericin (0, 0.5, 1, 2.5, and 5%). The results showed that the addition of 2.5 and 5% sericin in freezing medium significantly increased sperm viability and total motility (A + B) and decreased DNA fragmentation (P < 0.05). In experiment 2, semen samples were collected from 21 fertile men and were cryopreserved in freezing medium without any supplementation for 48 h. Then, the samples were thawed in medium supplemented with different concentrations of sericin (0, 0.5, 1, 2.5, and 5%). The addition of 5% sericin to thawing medium increased the total motility, viability, and decreased DNA fragmentation compared with those in thaws without sericin. In nutshell, the results clearly indicate the feasibility of sericin as an cryoprotective supplement for freezing media in human spermatozoa.

A simplified approach for efficient isolation of functional microglial cells: Application for modeling neuroinflammatory responses in vitro.

Purified microglial cells in culture are frequently used to model brain inflammatory responses but obtaining large yields of these cells on a routine basis can be quite challenging. Here, we demonstrate that it is possible to achieve high-yield isolation of pure microglial (MAC-1(+) /Fcrls(+) /Ccr2(-) ) cells from postnatal brain tissue through a simple culture procedure that mainly relies on the adhesion preference of these cells to the polycation polyethyleneimine (PEI) in serum-supplemented DMEM medium. Accordingly, other synthetic or biological substrates failed to mimic PEI effects under the same culture conditions. Replacement of DMEM by DMEM/F12 nutrient mixture did not permit microglial cell isolation on PEI coating, indicating that PEI effects were context-dependent. Remarkably, the lack of culture feeding during progression of microglial cell isolation strongly improved cell yield, suggesting that nutritional deprivation was required to optimize this process. When generated in large culture flasks coated with PEI, cultures of microglial cells were easily recovered by trypsin proteolysis to produce subcultures for functional studies. These cultures responded to lipopolysaccharide (LPS, 1-10 ng/ml) treatment by secreting pro-inflammatory cytokines such as TNF-α, IL-6, IL-1ß and by generating nitric oxide and reactive oxygen species. Most interestingly, this response was curtailed by appropriate reference drugs. Microglial cells were also strongly responsive to the mitogenic cytokine GM-CSF, which confirms that the functional repertoire of these cells was well preserved. Because of its high yield and simplicity, we believe that the present method will prove to be especially convenient for mechanistic studies or screening assays. GLIA 2016;64:1912-1924.

The protective effects of melatonin against cryopreservation-induced oxidative stress in human sperm.

Reactive oxygen species (ROS) production and lipid peroxidation during cryopreservation harm sperm membrane and as a result reduce the recovery of motile sperm. The antioxidant effects of melatonin on different cells have been widely reported. This study was aimed to evaluate changes in post-thaw motility, viability, and intracellular ROS and malondialdehyde (MDA) in response to the addition of melatonin to human sperm freezing extender. Semen of 43 fertile men was collected and each sample was divided into eight equal aliquots. An aliquot was analyzed freshly for viability, motility, and intracellular ROS and MDA. Melatonin was added to the recommended human freezing extender to yield six different final concentrations: 0.001, 0.005, 0.01, 0.05, 0.1, and 1 mM. A control group without melatonin was also included. Two weeks after cryopreservation, samples were thawed and pre-freeze analyses repeated. Obtained results showed that cryopreservation significantly (P <0.05) reduces viability and motility, but increases intracellular ROS and MDA of human sperm. The semen extender supplemented with various doses of melatonin (except for 0.001 mM) significantly (P <0.05) increased motility and viability, but decreased intracellular ROS and MDA levels of cryopreserved sperm after the thawing process, as compared with the control group. We also found that the most effective concentration of melatonin in protecting human spermatozoa from cryopreservation injuries was 0.01 mM. These findings suggest that melatonin exerts its cryoprotective effects on spermatozoa possibly by counteracting intracellular ROS, and thereby reduces MDA generation. This finally leads to increase of post-thaw viability and motility of cryopreserved spermatozoa.

Green One-Step Synthesis of Silver Nanoparticles Obtained from Schinus areira Leaf Extract: Characterization and Antibacterial Mechanism Analysis.

The increased emergence of antibiotic-resistant bacteria is a serious health problem worldwide. In this sense, silver nanoparticles (AgNPs) have received increasing attention for their antimicrobial activity. In this context, the goal of this study was to produce AgNPs by a green synthesis protocol using an aqueous leaf extract of Schinus areira as biocomposite to later characterize their antimicrobial action. The nanomaterials obtained were characterized by UV‒vis spectroscopy, DLS, TEM, and Raman, confirming the presence of quasi-spherical AgNPs with a negative surface charge and diameter around 11 nm. Afterward, the minimum inhibitory and bactericidal concentration of the AgNPs against Staphylococcus aureus and Escherichia coli were obtained, showing high antibacterial activity. In both of the examined bacteria, the AgNPs were able to raise intracellular ROS levels. In E. coli, the AgNPs can harm the bacterial membrane as well. Overall, it can be concluded that it was possible to obtain AgNPs with colloidal stability and antibacterial activity against Gram-positive and Gram-negative bacteria. Our findings point to at least two separate mechanisms that can cause cell death, one of which involves bacterial membrane damage and the other of which involves intracellular ROS induction.

Morinda citrifolia Essential Oil: A Plant Resistance Biostimulant and a Sustainable Alternative for Controlling Phytopathogens and Insect Pests.

With the growing demand for sustainable and safe agricultural practices, plant compounds emerge as a solution for biological activities. Here, we evaluated the potential of using Morinda citrifolia essential oil to induce plant resistance and to control phytopathogens (Curvularia lunata) and insect pests (Daubulus maidis). We conducted a chromatographic analysis to unveil the essential oil components. We also quantified the activity levels of antioxidant enzymes and chitinase for resistance induction. The antifungal action was evaluated through disease progression and the inhibition of mycelial growth in addition to in silico studies that made it possible to predict the interaction site between the fungal protein and the compounds. We assessed the toxicity and repellent actions towards the D. maidis. Octanoic acid (58.43%) was identified as the essential oil major compound. Preventive treatment with essential oil and octanoic acid (25.0 µL mL-1) increased not only the plant defense activities (i.e., the activity of the enzymes superoxide dismutase, catalase, phenol peroxidase, ascorbate peroxidase, and chitinase) but also controlled Curvularia leaf spot. The stable interactions between octanoic acid and tyrosine-tRNA ligase from C. lunata suggested protein synthesis inactivation. The essential oil inhibited 51.6% of mycelial growth, and this effect was increased to 75.9% with the addition of adjuvants (i.e., angico gum). The essential oil reduced 76% of the population of D. maidis adults and repelled 50% of the number of D. maidis after 48 h under field conditions. The repellency effect in the field reduced the population of D. maidis adults, transmitters of the stunting complex, by 50%. The results highlight the potential of M. citrifolia as a resistance activator, fungicide, insecticide, and an effective biorational alternative.

Bioavailable Phenolic Compounds from Olive Pomace Present Anti-Neuroinflammatory Potential on Microglia Cells.

The neuroinflammatory process is considered one of the main characteristics of central nervous system diseases, where a pro-inflammatory response results in oxidative stress through the generation of reactive oxygen and nitrogen species (ROS and RNS). Olive (Olea europaea L.) pomace is a by-product of olive oil production that is rich in phenolic compounds (PCs), known for their antioxidant and anti-inflammatory properties. This work looked at the antioxidant and anti-neuroinflammatory effects of the bioavailable PC from olive pomace in cell-free models and microglia cells. The bioavailable PC of olive pomace was obtained through the process of in vitro gastrointestinal digestion of fractionated olive pomace (OPF, particles size < 2 mm) and micronized olive pomace (OPM, particles size < 20 µm). The profile of the PC that is present in the bioavailable fraction as well as its in vitro antioxidant capacity were determined. The anti-neuroinflammatory capacity of the bioavailable PC from olive pomace (0.03-3 mg L-1) was evaluated in BV-2 cells activated by lipopolysaccharide (LPS) for 24 h. The total bioavailable PC concentration and antioxidant activity against peroxyl radical were higher in the OPM than those observed in the OPF sample. The activation of BV-2 cells by LPS resulted in increased levels of ROS and nitric oxide (NO). The bioavailable PCs from both OPF and OPM, at their lowest concentrations, were able to reduce the ROS generation in activated BV-2 cells. In contrast, the highest PC concentration of OPF and OPM was able to reduce the NO levels in activated microglial cells. Our results demonstrate that bioavailable PCs from olive pomace can act as anti-neuroinflammatory agents in vitro, independent of particle size. Moreover, studies approaching ways to increase the bioavailability of PCs from olive pomace, as well as any possible toxic effects, are needed before a final statement on its nutritional use is made.

Inactivation of SARS-CoV-2 on Surfaces by Cold-Plasma-Generated Reactive Species.

A Cold Atmospheric Plasma (CAP) apparatus was designed and developed for SARS-CoV-2 killing as evaluated by pseudotyped viral infectivity assays. The reactive species generated by the plasma system was fully characterized by using Optical Emission Spectroscopy (OES) measurement under given conditions such as plasma power, flow rate, and treatment time. A variety of reactive oxygen species (ROS) and reactive nitrogen species (RNS) were identified from plasma plume with energies of 15-72 eV in the frequency range between 500-1000 nm. Systematic virus killing experiments were carried out, and the efficacy of CAP treatment in reducing SARS-CoV-2 viral infectivity was significant following treatment for 8 s, with further enhancement of killing upon longer exposures of 15-120 s. We correlated killing efficacy with the reactive species in terms of type, intensity, energy, and frequency. These experimental results demonstrate effective cold plasma virus killing via ROS and RNS under ambient conditions.

Imidazolium salts as an alternative for anti-Leishmania drugs: Oxidative and immunomodulatory activities.

In this study we explored the previously established leishmanicidal activity of a complementary set of 24 imidazolium salts (IS), 1-hexadecylimidazole (C16Im) and 1-hexadecylpyridinium chloride (C16PyrCl) against Leishmania (Leishmania) amazonensis and Leishmania (Leishmania) infantum chagasi. Promastigotes of L. amazonensis and L. infantum chagasi were incubated with 0.1 to 100 µM of the compounds and eight of them demonstrated leishmanicidal activity after 48 h - C10MImMeS (IC50 L. amazonensis = 11.6), C16MImPF6(IC50 L. amazonensis = 6.9), C16MImBr (IC50 L. amazonensis = 6), C16M2ImCl (IC50 L. amazonensis = 4.1), C16M4ImCl (IC50 L. amazonensis = 1.8), (C10)2MImCl (IC50 L. amazonensis = 1.9), C16Im (IC50 L. amazonensis = 14.6), and C16PyrCl (IC50 L. amazonensis = 4).The effect of IS on reactive oxygen species production, mitochondrial membrane potential, membrane integrity and morphological alterations of promastigotes was determined, as well as on L. amazonensis-infected macrophages. Their cytotoxicity against macrophages and human erythrocytes was also evaluated. The IS C10MImMeS, C16MImPF6, C16MImBr, C16M2ImCl, C16M4ImCl and (C10)2MImCl, and the compounds C16Im and C16PyrCl killed and inhibited the growth of promastigote forms of L. amazonensis and L. infantum chagasi in a concentration-dependent manner, contributing to a better understanding of the structure-activity relationship of IS against Leishmania. These IS induced ROS production, mitochondrial dysfunction, membrane disruption and morphological alterations in infective forms of L. amazonensis and killed intracellular amastigote forms in very low concentrations (IC50 amastigotes ≤ 0.3), being potential drug candidates against L. amazonensis.

Gains from no real PAINS: Where 'Fair Trial Strategy' stands in the development of multi-target ligands.

Compounds that selectively modulate multiple targets can provide clinical benefits and are an alternative to traditional highly selective agents for unique targets. High-throughput screening (HTS) for multitarget-directed ligands (MTDLs) using approved drugs, and fragment-based drug design has become a regular strategy to achieve an ideal multitarget combination. However, the unexpected presence of pan-assay interference compounds (PAINS) suspects in the development of MTDLs frequently results in nonspecific interactions or other undesirable effects leading to artefacts or false-positive data of biological assays. Publicly available filters can help to identify PAINS suspects; however, these filters cannot comprehensively conclude whether these suspects are "bad" or innocent. Additionally, these in silico approaches may inappropriately label a ligand as PAINS. More than 80% of the initial hits can be identified as PAINS by the filters if appropriate biochemical tests are not used resulting in false positive data that are unacceptable for medicinal chemists in manuscript peer review and future studies. Therefore, extensive offline experiments should be used after online filtering to discriminate "bad" PAINS and avoid incorrect evaluation of good scaffolds. We suggest that the use of "Fair Trial Strategy" to identify interesting molecules in PAINS suspects to provide certain structure‒function insight in MTDL development.

Regulatory Mechanisms of Baicalin in Cardiovascular Diseases: A Review.

Cardiovascular diseases (CVDs) is the leading cause of high morbidity and mortality worldwide, which emphasizes the urgent necessity to develop new pharmacotherapies. In eastern countries, traditional Chinese medicine Scutellaria baicalensis Georgi has been used clinically for thousands of years. Baicalin is one of the main active ingredients extracted from Chinese herbal medicine S. baicalensis. Emerging evidence has established that baicalin improves chronic inflammation, immune imbalance, disturbances in lipid metabolism, apoptosis and oxidative stress. Thereby it offers beneficial roles against the initiation and progression of CVDs such as atherosclerosis, hypertension, myocardial infarction and reperfusion, and heart failure. In this review, we summarize the pharmacological features and relevant mechanisms by which baicalin regulates CVDs in the hope to reveal its application for CVDs prevention and/or therapy.

Environmental and Nutritional "Stressors" and Oligodendrocyte Dysfunction: Role of Mitochondrial and Endoplasmatic Reticulum Impairment.

Oligodendrocytes are myelinating cells of the central nervous system which are generated by progenitor oligodendrocytes as a result of maturation processes. The main function of mature oligodendrocytes is to produce myelin, a lipid-rich multi-lamellar membrane that wraps tightly around neuronal axons, insulating them and facilitating nerve conduction through saltatory propagation. The myelination process requires the consumption a large amount of energy and a high metabolic turnover. Mitochondria are essential organelles which regulate many cellular functions, including energy production through oxidative phosphorylation. Any mitochondrial dysfunction impacts cellular metabolism and negatively affects the health of the organism. If the functioning of the mitochondria is unbalanced, the myelination process is impaired. When myelination has finished, oligodendrocyte will have synthesized about 40% of the total lipids present in the brain. Since lipid synthesis occurs in the cellular endoplasmic reticulum, the dysfunction of this organelle can lead to partial or deficient myelination, triggering numerous neurodegenerative diseases. In this review, the induced malfunction of oligodendrocytes by harmful exogenous stimuli has been outlined. In particular, the effects of alcohol consumption and heavy metal intake are discussed. Furthermore, the response of the oligodendrocyte to excessive mitochondrial oxidative stress and to the altered regulation of the functioning of the endoplasmic reticulum will be explored.

Therapeutic Potential of Porcine Liver Decomposition Product: New Insights and Perspectives for Microglia-Mediated Neuroinflammation in Neurodegenerative Diseases.

It is widely accepted that microglia-mediated inflammation contributes to the progression of neurodegenerative diseases; however, the precise mechanisms through which these cells contribute remain to be elucidated. Microglia, as the primary immune effector cells of the brain, play key roles in maintaining central nervous system (CNS) homeostasis. Microglia are located throughout the brain and spinal cord and may account for up to 15% of all cells in the brain. Activated microglia express pro-inflammatory cytokines that act on the surrounding brain and spinal cord. Microglia may also play a detrimental effect on nerve cells when they gain a chronic inflammatory function and promote neuropathologies. A key feature of microglia is its rapid morphological change upon activation, characterized by the retraction of numerous fine processes and the gradual acquisition of amoeba-like shapes. These morphological changes are also accompanied by the expression and secretion of inflammatory molecules, including cytokines, chemokines, and lipid mediators that promote systemic inflammation during neurodegeneration. This may be considered a protective response intended to limit further injury and initiate repair processes. We previously reported that porcine liver decomposition product (PLDP) induces a significant increase in the Hasegawa's Dementia Scale-Revised (HDS-R) score and the Wechsler Memory Scale (WMS) in a randomized, double-blind, placebo-controlled study in healthy humans. In addition, the oral administration of porcine liver decomposition product enhanced visual memory and delayed recall in healthy adults. We believe that PLDP is a functional food that aids cognitive function. In this review, we provide a critical assessment of recent reports of lysophospholipids derived from PLDP, a rich source of phospholipids. We also highlight some recent findings regarding bidirectional interactions between lysophospholipids and microglia and age-related neurodegenerative diseases such as dementia and Alzheimer's disease.

Chemical composition and phytotoxicity of essential oils of Croton doctoris S. Moore (Euphorbiaceae) / Composição química e fitotoxicidade dos óleos essenciais de Croton doctoris S. Moore (Euphorbiaceae)

Essential oils from the stems and leaves of Croton doctoris were analyzed by gas chromatography and mass spectrometry, resulting in 22 identified compounds. The effects of these essential oils on the germination, root and shoot growth, total chlorophyll content, potential root respiration, peroxidase activity, catalase, superoxide dismutase, and mitotic index in lettuce and onion were determined. Antioxidant, antimicrobial, and cytotoxic activity were also investigated. The results revealed that the stem oil consisted of 15 compounds, of which caryophyllene oxide (24.5%) and E-caryophyllene (13.3%) were the major constituents. The leaf oil contained E-caryophyllene (39.6%) and α-humulene (13.2%) as major compounds. The oils inhibited the germination and growth of lettuce and onion seedlings and reduced chlorophyll content, root respiration, and cell division. They also caused oxidative stress, indicated by the increased activity of the evaluated antioxidant enzymes. These abnormal physiological processes contributed to the inhibition of plant growth. The most pronounced phytotoxic effects were observed in the stem oil. The cytotoxicity tests indicated that leaf oil was more active than stem oil, resulting from the presence of biologically active sesquiterpenes that inhibit the growth of cancer cells.

Os óleos essenciais do caule e da folha de Croton doctoris foram analisados por cromatografia gasosa (GC) e espectrometria de massa (GC-MS) resultando em 22 compostos identificados. Os efeitos dos óleos essenciais na germinação, crescimento de raízes e parte aérea, teor total de clorofila, respiração radicular, atividade de peroxidase, catalase e superóxido de dimetase e índice mitótico foram determinados em alface e cebola. Atividade antioxidante, antimicrobiana e citotóxica também foram investigadas. Os resultados revelaram que o óleo do caule é constituído por 15 compostos, dos quais os principais são o óxido de cariofileno (24,5%) e E-cariofileno (13,3%). O óleo foliar apresentou E-cariofileno (39,6%) seguido de α-humuleno (13,2%) como compostos majoritários. Os óleos inibiram a germinação e o crescimento das plântulas de alface e cebola e reduziram o conteúdo de clorofila, a respiração radicular e a divisão celular. Eles também causaram estresse oxidativo, indicado pelo aumento da atividade das enzimas antioxidantes avaliadas. Esses processos fisiológicos anormais contribuem para a inibição do crescimento das plantas. Os efeitos fitotóxicos mais pronunciados foram observados no óleo do caule. Nos testes de citotoxicidade observou-se que o óleo das folhas foi mais ativo, resultante da presença de sesquiterpenos biologicamente ativos que atuam inibindo o crescimento das células cancerígenas.

Chemical composition and phytotoxicity of essential oils of Croton doctoris S. Moore (Euphorbiaceae)

Abstract Essential oils from the stems and leaves of Croton doctoris were analyzed by gas chromatography and mass spectrometry, resulting in 22 identified compounds. The effects of these essential oils on the germination, root and shoot growth, total chlorophyll content, potential root respiration, peroxidase activity, catalase, superoxide dismutase, and mitotic index in lettuce and onion were determined. Antioxidant, antimicrobial, and cytotoxic activity were also investigated. The results revealed that the stem oil consisted of 15 compounds, of which caryophyllene oxide (24.5%) and E-caryophyllene (13.3%) were the major constituents. The leaf oil contained E-caryophyllene (39.6%) and -humulene (13.2%) as major compounds. The oils inhibited the germination and growth of lettuce and onion seedlings and reduced chlorophyll content, root respiration, and cell division. They also caused oxidative stress, indicated by the increased activity of the evaluated antioxidant enzymes. These abnormal physiological processes contributed to the inhibition of plant growth. The most pronounced phytotoxic effects were observed in the stem oil. The cytotoxicity tests indicated that leaf oil was more active than stem oil, resulting from the presence of biologically active sesquiterpenes that inhibit the growth of cancer cells.

Resumo Os óleos essenciais do caule e da folha de Croton doctoris foram analisados por cromatografia gasosa (GC) e espectrometria de massa (GC-MS) resultando em 22 compostos identificados. Os efeitos dos óleos essenciais na germinação, crescimento de raízes e parte aérea, teor total de clorofila, respiração radicular, atividade de peroxidase, catalase e superóxido de dimetase e índice mitótico foram determinados em alface e cebola. Atividade antioxidante, antimicrobiana e citotóxica também foram investigadas. Os resultados revelaram que o óleo do caule é constituído por 15 compostos, dos quais os principais são o óxido de cariofileno (24,5%) e E-cariofileno (13,3%). O óleo foliar apresentou E-cariofileno (39,6%) seguido de -humuleno (13,2%) como compostos majoritários. Os óleos inibiram a germinação e o crescimento das plântulas de alface e cebola e reduziram o conteúdo de clorofila, a respiração radicular e a divisão celular. Eles também causaram estresse oxidativo, indicado pelo aumento da atividade das enzimas antioxidantes avaliadas. Esses processos fisiológicos anormais contribuem para a inibição do crescimento das plantas. Os efeitos fitotóxicos mais pronunciados foram observados no óleo do caule. Nos testes de citotoxicidade observou-se que o óleo das folhas foi mais ativo, resultante da presença de sesquiterpenos biologicamente ativos que atuam inibindo o crescimento das células cancerígenas.

Chemical composition and phytotoxicity of essential oils of Croton doctoris S. Moore (Euphorbiaceae) / Composição química e fitotoxicidade dos óleos essenciais de Croton doctoris S. Moore (Euphorbiaceae)

Essential oils from the stems and leaves of Croton doctoris were analyzed by gas chromatography and mass spectrometry, resulting in 22 identified compounds. The effects of these essential oils on the germination, root and shoot growth, total chlorophyll content, potential root respiration, peroxidase activity, catalase, superoxide dismutase, and mitotic index in lettuce and onion were determined. Antioxidant, antimicrobial, and cytotoxic activity were also investigated. The results revealed that the stem oil consisted of 15 compounds, of which caryophyllene oxide (24.5%) and E-caryophyllene (13.3%) were the major constituents. The leaf oil contained E-caryophyllene (39.6%) and α-humulene (13.2%) as major compounds. The oils inhibited the germination and growth of lettuce and onion seedlings and reduced chlorophyll content, root respiration, and cell division. They also caused oxidative stress, indicated by the increased activity of the evaluated antioxidant enzymes. These abnormal physiological processes contributed to the inhibition of plant growth. The most pronounced phytotoxic effects were observed in the stem oil. The cytotoxicity tests indicated that leaf oil was more active than stem oil, resulting from the presence of biologically active sesquiterpenes that inhibit the growth of cancer cells.

Os óleos essenciais do caule e da folha de Croton doctoris foram analisados por cromatografia gasosa (GC) e espectrometria de massa (GC-MS) resultando em 22 compostos identificados. Os efeitos dos óleos essenciais na germinação, crescimento de raízes e parte aérea, teor total de clorofila, respiração radicular, atividade de peroxidase, catalase e superóxido de dimetase e índice mitótico foram determinados em alface e cebola. Atividade antioxidante, antimicrobiana e citotóxica também foram investigadas. Os resultados revelaram que o óleo do caule é constituído por 15 compostos, dos quais os principais são o óxido de cariofileno (24,5%) e E-cariofileno (13,3%). O óleo foliar apresentou E-cariofileno (39,6%) seguido de α-humuleno (13,2%) como compostos majoritários. Os óleos inibiram a germinação e o crescimento das plântulas de alface e cebola e reduziram o conteúdo de clorofila, a respiração radicular e a divisão celular. Eles também causaram estresse oxidativo, indicado pelo aumento da atividade das enzimas antioxidantes avaliadas. Esses processos fisiológicos anormais contribuem para a inibição do crescimento das plantas. Os efeitos fitotóxicos mais pronunciados foram observados no óleo do caule. Nos testes de citotoxicidade observou-se que o óleo das folhas foi mais ativo, resultante da presença de sesquiterpenos biologicamente ativos que atuam inibindo o crescimento das células cancerígenas.

Inoculation of corn seeds with Azospirillum brasilense in different temperatures / Inoculation of corn seeds with Azospirillum brasilense in different temperatures

Growth-promoting bacteria Azospirillum brasilense, used as an inoculant in corn culture, can be severely affected by the exposure temperature, with a lethal effect above 35°C, when cultivated alone under laboratory conditions. Such effects may limit the associative interaction between plant-bacteria, with reduced inoculation efficiency, resulting in a lower growth rate of the plant and an increase in oxidative stress. Thus, the objective of the research was to evaluate the efficiency of the inoculation process with A. brasilense in seeds and in the initial growth of seedlings of two corn cultivars submitted to different temperatures. Were utilized corn hybrids seed Syn 488 and Syn 505. The experimental design was completely randomized in a 2 x 4 factorial scheme (with and without inoculation of A. brasilense x 4 sowing temperatures: 20, 25, 30, and 35ºC), with four replications. The inoculation efficiency in corn seedlings submitted to different temperatures was evaluated through the following tests: germination, first count, seedling length and dry weight. In addition, responses at the biochemical level of the interaction (temperatures x inoculation) for the content of photosynthetic pigments and hydrogen peroxide (H2O2), antioxidant enzymes and lipid peroxidation were evaluated. The inoculation with A. brasilense changed the morphological and biochemical responses of corn see

Growth-promoting bacteria Azospirillum brasilense, used as an inoculant in corn culture, can be severely affected by the exposure temperature, with a lethal effect above 35°C, when cultivated alone under laboratory conditions. Such effects may limit the associative interaction between plant-bacteria, with reduced inoculation efficiency, resulting in a lower growth rate of the plant and an increase in oxidative stress. Thus, the objective of the research was to evaluate the efficiency of the inoculation process with A. brasilense in seeds and in the initial growth of seedlings of two corn cultivars submitted to different temperatures. Were utilized corn hybrids seed Syn 488 and Syn 505. The experimental design was completely randomized in a 2 x 4 factorial scheme (with and without inoculation of A. brasilense x 4 sowing temperatures: 20, 25, 30, and 35ºC), with four replications. The inoculation efficiency in corn seedlings submitted to different temperatures was evaluated through the following tests: germination, first count, seedling length and dry weight. In addition, responses at the biochemical level of the interaction (temperatures x inoculation) for the content of photosynthetic pigments and hydrogen peroxide (H2O2), antioxidant enzymes and lipid peroxidation were evaluated. The inoculation with A. brasilense changed the morphological and biochemical responses of corn see

Glucocorticoids alter neuronal differentiation of human neuroepithelial-like cells by inducing long-lasting changes in the reactive oxygen species balance.

Prenatal exposure to excess glucocorticoid has been shown to have adverse effects on the developing nervous system that may lead to alterations of fetal and adult neurogenesis, resulting in behavioral changes. In addition, an imbalance of the redox state, with an increased susceptibility to oxidative stress, has been observed in rodent neural stem cells exposed to the synthetic glucocorticoid analog dexamethasone (Dex). In the present study, we used the induced pluripotent stem cells (IPSC)-derived lt-NES AF22 cell line, representative of the neuroepithelial stage in central nervous system development, to investigate the heritable effects of Dex on reactive oxygen species (ROS) balance and its impact on neuronal differentiation. By analysing gene expression in daughter cells that were never directly exposed to Dex, we could observe a downregulation of four key antioxidant enzymes, namely Catalase, superoxide dismutase 1, superoxide dismutase 2 and glutathione peroxidase7, along with an increased intracellular ROS concentration. The imbalance in the intracellular REDOX state was associated to a significant downregulation of major neuronal markers and a concomitant increase of glial cells. Interestingly, upon treatment with the antioxidant N-acetyl-cysteine (NAC), the misexpression of both neuronal and glial markers analyzed was recovered. These novel findings point to the increased ROS concentration playing a direct role in the heritable alterations of the differentiation potential induced by Dex exposure. Moreover, the data support the hypothesis that early insults may have detrimental long-lasting consequences on neurogenesis. Based on the positive effects exerted by NAC, it is conceivable that therapeutic strategies including antioxidants may be effective in the treatment of neuropsychiatric disorders that have been associated to increased ROS and impaired neurogenesis.

El estrés oxidativo y los antioxidantes en la prevención del cáncer / Oxidative stress and antioxidants in cancer prevention

Introducción: el estrés oxidativo participa en la carcinogénesis; por ello, se ha considerado como estrategia para la prevención del cáncer el reforzamiento de los mecanismos celulares de defensa antioxidante. Objetivo: evaluar el papel del estrés oxidativo en el proceso de carcinogénesis, así como la utilidad y modalidades de uso de los antioxidantes en su prevención. Métodos: se realizó un trabajo de revisión bibliográfica a través de la consulta de Google, LILACS, PubMed y Hinari. Se seleccionaron artículos de revisión sobre el tema, de los últimos 5 años, así como revisiones sistemáticas y meta-análisis publicados que evalúan la utilización de suplementos de antioxidantes sintéticos en la prevención del cáncer. Desarrollo: se abordan los mecanismos carcinogénicos de las especies reactivas del oxígeno y se discuten los beneficios y amenazas del uso preventivo de suplementos de antioxidantes. También se analiza el posible impacto en el control del estrés oxidativo, la aplicación de las recomendaciones plasmadas en la Estrategia Global sobre la Dieta, la Actividad Física y la Salud de la Organización Mundial de la Salud. Finalmente, se enfatiza en los mecanismos anticarcinogénicos de diferentes fitoquímicos. Conclusiones: la promoción de hábitos saludables que evita la generación de las especies reactivas del oxígeno, unido a la ingestión de antioxidantes como componentes de la dieta, pueden conducir al equilibrio apropiado oxidantes/antioxidantes y consecuentemente a la prevención del cáncer.

Introduction: oxidative stress is involved in carcinogenesis. Consequently, the reinforcement of cellular defensive antioxidant mechanisms has been considered as strategy for cancer prevention. Objective: to evaluate the role of oxidative stress in the carcinogenesis process as well as the utility and modalities of the use of antioxidants in cancer prevention. Methods: a review was performed through the consultation of Google, LILACS, PubMed and Hinari. Review articles published in the last five years, systematic reviews and meta-analysis about the evaluation of antioxidants for cancer prevention were selected. Results: the carcinogenic mechanisms of oxygen reactive species, and the benefits and threats of antioxidant supplementation are discussed. Finally, the possible impact on oxidative stress control, of implementation of the WHO Global Strategy on Diet Physical Activity and Health is analyzed, empathizing in the anticarcinogenic mechanisms of different phytochemicals. Conclusions: the promotion of healthy habits which avoid the generation of oxygen reactive species, together with the intake of antioxidants as dietary components could lead to the appropriate balance oxidants/antioxidants and consequently to cancer prevention.

Diferencias del estado redox entre espermatozoides y plasma seminal en adultos jóvenes / Difference of redux status between spermatozoa and seminal plasma in young adults

Introducción: Las especies reactivas del oxígeno y el estrés oxidativo desempeñan un papel fundamental en la infertilidad masculina. Sin embargo, estas especies oxidantes también han sido asociadas con los procesos de capacitación de los gametos masculinos cuando son generadas a bajos niveles y de manera controlada. Actualmente los biomarcadores redox son introducidos en el diagnóstico clínico de la infertilidad masculina en el mundo, como una herramienta complementaria a los parámetros del espermiograma. Sin embargo, en Cuba, esta metodología aún no se encuentra extendida a los servicios de salud. Objetivo: El objetivo del presente trabajo fue caracterizar el estado redox de espermatozoides y el líquido seminal de sujetos aparentemente sanos, a través de la determinación de una serie de biomarcadores de estrés oxidativo. Los niveles de malonildialdehído, la actividad de las enzimas antioxidantes superóxido dismutasa y catalasa, así como los niveles de glutatión reducido, el potencial de peroxidación y la capacidad reductora fueron determinados mediante técnicas espectrofotométricas. Métodos: Se analizaron 40 muestras de semen de sujetos aparentemente sanos, las cuales fueron obtenidas mediante masturbación sin el empleo de lubricantes y con al menos tres días de abstinencia eyaculatoria. En el estudio se incluyeron sujetos de 20 a 35 años, aparentemente sanos según exámenes de laboratorio clínico y con paternidad probada. Resultados: Los resultados demostraron que existen diferencias significativas (p< 0,05) entre los marcadores evaluados en el líquido seminal con respecto al espermatozoide, lo cual sugiere la existencia de un estado redox diferenciado entre ambos compartimentos. Conclusiones: Estos hallazgos demuestran la necesidad de evaluar el nivel de estrés oxidativo tanto en las células sexuales como en el fluido que las contiene. Ello contribuirá, sin lugar a dudas, a un diagnóstico más eficaz e integral de la capacidad fértil del hombre

Background: Reactive oxygen species and oxidative stress play a fundamental role in male infertility. However, these oxidizing species have also been associated with the process of capability of male gametes when they are generated at low levels and in a controlled manner. Currently, redox biomarkers are introduced in the clinical diagnosis of male infertility in the world as a complementary tool to the spermiogram parameters. However, in Cuba, this methodology is not yet extended to health services. Objective: The objective of this study was to characterize the redox status of spermatozoa and seminal fluid of apparently healthy subjects through the identification of a number of biomarkers of oxidative stress. Methods: 40 samples of semen of apparently healthy subjects were analyzed, which were obtained by masturbation without the use of lubricants and with at least 3 days of ejaculatory abstinence. The study included subjects from 20 to 35 years of age, who were apparently healthy according to both laboratory tests and paternity test results. Results: The results showed that there are significant differences (p<0, 05) between the markers evaluated in the seminal fluid and the spermatozoon which suggests the existence of a differentiated redux status between the two compartments. Conclusions: These findings demonstrate the need to evaluate the level of oxidative stress in both sexual cells and the fluid that contains them. It will contribute, with no doubt, to a more effective and comprehensive diagnosis of man's fertility