Antiproliferative Effect of Inorganic and Organic Selenium Compounds in Breast Cell Lines.

Triple-negative breast cancer (TNBC) is an aggressive, fast-growing tumor that is more likely to spread to distant organs. Among women diagnosed with breast cancer, the prevalence of TNBC is 20%, and treatment is currently limited to chemotherapy. Selenium (Se), an essential micronutrient, has been explored as an antiproliferative agent. Therefore, this study aimed to evaluate the effects of exposure to organic (selenomethionine, ebselen, and diphenyl diselenide) and inorganic (sodium selenate and sodium selenite) Se molecules in different breast cell lines. The compounds were tested at 1, 10, 50, and 100 µM for 48 h in the non-tumor breast cell line (MCF-10A) and TNBC derivatives cell lines (BT-549 and MDA-MB-231). The effects of Se on cell viability, apoptotic and necrotic processes, colony formation, and cell migration were analyzed. Exposure to selenomethionine and selenate did not alter the evaluated parameters. However, selenomethionine had the highest selectivity index (SI). The exposure to the highest doses of selenite, ebselen, and diphenyl diselenide resulted in antiproliferative and antimetastatic effects. Selenite had a high SI to the BT cell line; however, the SI of ebselen and diphenyl diselenide was low in both tumoral cell lines. In conclusion, the Se compounds had different effects on the breast cell lines, and additional tests are needed to reveal the antiproliferative effects of Se compounds.

Adulticidal Activity of Melaleuca alternifolia (Myrtales: Myrtaceae) Essential Oil With High 1,8-Cineole Content Against Stable Flies (Diptera: Muscidae).

The stable fly, Stomoxys calcitrans (Linnaeus 1758), is a hematophagous fly responsible for causing loss of performance in horses, causing losses in cattle productivity, and impacting the animals' health through the spread of pathogenic microorganisms. The objective of this work was to investigate the insecticidal activity of essential oil obtained from Melaleuca alternifolia (Cheel), presenting high 1,8-cineole content, against S. calcitrans adults. Insecticidal activity was determined using surface application methods and exposure to oil impregnated paper. It was observed that treatments at 25 and 50 µg/cm2 (P < 0.05) present fumigant activity through exposure to the impregnated paper, and in the first 15 min of exposure, the mortality rates obtained for these treatments were, respectively (96.6 ± 3.3% and 100%), equivalent to the positive control. Using the superficial application method, the only treatment concentration presenting adulticidal action was 5% (w/v) (P < 0.05). Respective toxicities LC50 (%, w/v) and LC80 for the impregnated paper method were 1.06 ± 0.02 and 1.47 ± 0.17; for the superficial application method, they were 3.82 ± 0.65 and 5.53 ± 0.74. As demonstrated, M. alternifolia essential oil presents adulticidal potential against S. calcitrans.

Delta-Aminolevulinate dehydratase and glutathione peroxidase activity in Alzheimer's disease: a case-control study.

Alzheimer's disease (AD) is a neurodegenerative pathology that affects elderly people all over the world. Several studies have demonstrated that oxidative stress is an aggravating factor for AD development and progression. Therefore, this study aimed to evaluate the activity of two oxidative stress markers, glutathione peroxidase (GPx) and δ-aminolevulinate dehydratase (δ-ALA-D), as well as correlate them with blood metal levels and AD progression. For this purpose, 88 elderly individuals were divided in two groups: AD group (34 patients diagnosed with AD) and control group (34 subjects paired by age with the AD group). The Mini-Mental State Examination and the Clinical Dementia Rating (CDR) were used as tools to classify the AD progression. GPx and δ-ALA-D activities were measured in all subjects through blood tests. Both enzymes' activities were decreased in AD patients when compared to the age-matched control group, regardless of the CDR. Moreover, GPx activity was positively correlated with selenium levels in the blood; and the δ-ALA-D activity was negatively correlated with blood copper levels. Taken together, our results indicated that, for the first time, blood δ-ALA-D activity was significantly inhibited in AD patients. While literature reports conflicting data regarding GPx activity in AD patients, the δ-ALA-D activity seems to be a more consistent tool to be applied as an earlier AD marker.

Nectandra grandiflora essential oil and its isolated sesquiterpenoids minimize anxiety-related behaviors in mice through GABAergic mechanisms.

Nectandra grandiflora Ness (Lauraceae) essential oil (EO) main constituent, the sesquiterpenoid (+)-dehydrofukinone (DHF), has sedative and anticonvulsant effects through GABAergic mechanisms. Other DHF-related sesquiterpenoids have been identified in the EO, such as, dehydrofukinone epoxide (DFX), eremophil-11-en-10-ol (ERM) and selin-11-en-4-α-ol (SEL). However, the neuronal effects of these compounds in mammals remain unknown. Therefore, the aim of this study was to evaluate the anxiolytic potential of the N. grandiflora EO and the isolated compounds in in mice. For this purpose, mice were administered orally with vehicle, 10, 30 or 100 mg/kg EO, DHF, DFX, ERM or SEL or 1 mg/kg diazepam. Locomotion and ethological parameters in the open field (OF) and elevated plus maze (EPM) were recorded. We also examined the effect of DFX, ERM and SEL on the membrane potential and calcium influx in synaptosomes, and the presence of the compounds in the cortical tissue using gas chromatography. EOs and isolated compounds reduced anxiety-related parameters in the EPM (open arms time and entries, end activity, head dipping) and OF (center time and entries, total rearing, unprotected rearing, sniffing, grooming) without alter ambulation or induce sedation. Flumazenil (2 mg/kg, i.p.) altered the anxiolytic-like effect of all treatments and vanished the DFX, ERM and SEL-induced changes in membrane potential. However, FMZ did not blocked the DFX-, ERM- and SEL-induced inhibition of calcium influx. Therefore, our results suggest that N. grandiflora EO and isolated compounds induced anxiolytic-like effect in mice due to positive modulation of GABAa receptors and/or inhibition of neuronal calcium influx.

Effect of meteorological elements on the content and composition of Aloysia triphylla (L´Hérit) Britton essential oil / Efecto de los elementos meteorológicos sobre el contenido y la composición del aceite esencial de Aloysia triphylla (L´Hérit) Britton

The concentration and composition of an essential oil can vary according to environmental variations and seasonal periods. The objective of this study was to correlate meteorological elements with the content and concentration of components of Aloysia triphylla essential oil, for the four seasons of the year. The experiment was conducted in a plastic greenhouse of the UFSM, Frederico Westphalen campus ­ RS, Brazil, in a complete randomized blocks design during the four seasons, with three repetitions. The meteorological data were collected with the aid of a compact meteorological station, in order to characterize the environment in which the species was conducted. The evaluations were carried out at the middle date of each season. It was observed a correlation between the meteorological variables with the essential oil production and its components. According to the analysis, there influence of the temperature on the essential oil contents, considering that the maximum temperature shows a direct positive influence on the concentration of limonene and negative for spathulenol.

El contenido y la composición de un aceite esencial pueden variar según las variaciones ambientales y los períodos estacionales. El objetivo de este estudio fue correlacionar los elementos meteorológicos con el contenido y la concentración de los componentes del aceite esencial de Aloysia triphylla, para las cuatro estaciones del año. El experimento se realizó en un invernadero de plástico de la UFSM, campus de Frederico Westphalen - RS, Brasil, en un diseño completo de bloques al azar durante las cuatro estaciones, con tres repeticiones. Los datos meteorológicos se recopilaron con la ayuda de una estación meteorológica compacta, para caracterizar el entorno en el que se realizó la especie. Las evaluaciones se llevaron a cabo en la fecha media de cada temporada. Se observó una correlación entre las variables meteorológicas con la producción de aceites esenciales y sus componentes. De acuerdo con el análisis, existe una influencia de la temperatura en los contenidos de aceites esenciales, considerando que la temperatura máxima muestra una influencia positiva directa sobre la concentración de limoneno y negativa para el espatulenol.

(+)-Dehydrofukinone modulates membrane potential and delays seizure onset by GABAa receptor-mediated mechanism in mice.

(+)-Dehydrofukinone (DHF), isolated from Nectandra grandiflora (Lauraceae) essential oil, induces sedation and anesthesia by modulation of GABAa receptors. However, no study has addressed whether DHF modulates other cellular events involved in the control of cellular excitability, such as seizure behavior. Therefore, the aim of the present study was to investigate the effect of DHF on cellular excitability and seizure behavior in mice. For this purpose, we used isolated nerve terminals (synaptosomes) to examine the effect of DHF on the plasma membrane potential, the involvement of GABAa receptors and the downstream activation of Ca2+ mobilization. Finally, we performed an in vivo assay in order to verify whether DHF could impact on seizures induced by pentylenetetrazole (PTZ) in mice. The results showed that DHF induced a GABA-dependent sustained hyperpolarization, sensitive to flumazenil and absent in low-[Cl-] medium. Additionally, (1-100µM) DHF decreased KCl-evoked calcium mobilization over time in a concentration-dependent manner and this effect was prevented by flumazenil. DHF increased the latency to myoclonic jerks (10mg/kg), delayed the onset of generalized tonic-clonic seizures (10, 30 and 100mg/kg), and these effects were also blocked by the pretreatment with flumazenil. Our data indicate that DHF has anticonvulsant properties and the molecular target underlying this effect is likely to be the facilitation of GABAergic neuronal inhibition. The present study highlights the therapeutic potential of the natural compound DHF as a suppressor of neuronal excitability.

Anesthetic activity of the essential oil of Ocimum americanum in Rhamdia quelen (Quoy & Gaimard, 1824) and its effects on stress parameters

The aim of this study was to evaluate the anesthetic activity of the essential oil (EO) of Ocimum americanum L. in silver catfish (Rhamdia quelen ). In the first experiment, the depressor effects and chemical composition of the leaf EO (LEO) and inflorescence EO (IEO) were compared. Juveniles (n = 10) were placed in aquaria containing different concentrations of EO (25 - 500 mg L-1) to determine the point at which anesthesia was induced and the length of the recovery period. In the following experiment, the effects of 300 and 500 mg L-1 LEO exposure on stress parameters (plasma cortisol, glucose and sodium levels) after air exposure for 1 min were assayed. Fish (n = 10 per sampling time) were sampled immediately or transferred to anesthetic-free aquaria until sampling (15, 30, 60 or 240 min). LEO was composed mainly of β-linalool and 1,8-cineole in similar proportions, whereas IEO showed β-linalool as major compound. Anesthesia was obtained in silver catfish with 200-500 mg L-1 between 4-8 min for LEO and 6-16 min for IEO. Lower EO concentrations did not reach anesthetic stage up to 30 min. LEO used as anesthetic prevented the cortisol increase and sodium loss induced by aerial exposure. Glucose levels were raised in catfish exposed to LEO compared to basal group (not air exposed) in almost all observation times. EO of O. americanum obtained from leaves was considered suitable to anesthetic procedures due to its fast induction and handling-induced stress prevention.

O objetivo deste trabalho foi avaliar a atividade anestésica do óleo essencial (EO) de Ocimum americanum L. em jundiás (Rhamdia quelen ). No primeiro experimento, os efeitos depressores e a composição química dos óleos obtidos a partir das folhas (LEO) e das inflorescências (IEO) desta espécie vegetal foram comparados. Para isto, juvenis de jundiás (n = 10) foram transferidos para aquários contendo diferentes concentrações de EO (25 - 500 mg L-1) a fim de determinar os tempos de indução aos estágios de anestesia e de recuperação. No experimento seguinte foram determinados os efeitos da exposição a 300 e 500 mg L-1 de LEO em parâmetros de estresse (cortisol, glicose e níveis de sódio plasmáticos) após os animais serem expostos durante 1 min ao ar. Os peixes (n = 10 por tempo de amostragem) foram coletados imediatamente ou transferidos para aquários livres de anestésico até amostragem (15, 30, 60 ou 240 min). LEO demonstrou ser composto majoritariamente por β-linalol e 1,8-cineol em proporções similares, enquanto que IEO apresentou β-linalol como constituinte majoritário. O estágio de anestesia foi verificado em jundiás com 200-500 mg L-1 entre 4-8 min para LEO e 6-16 min para IEO. Menores concentrações de ambos os EO não promoveram anesthesia até 30 min. O uso de LEO como anestésico preveniu o aumento de cortisol e a perda de sódio induzida pela exposição aérea. Já a glicemia encontrava-se aumentada em peixes expostos ao LEO em comparação ao grupo basal (não exposto ao ar) na maioria dos tempos de observação. Assim, EO de O. americanum obtido a partir das folhas foi considerado adequado para procedimentos anestésicos devido a sua rápida indução e capacidade de prevenir o estresse decorrente do manuseio.

Anesthetic activity of Brazilian native plants in silver catfish (Rhamdia quelen)

There is an increasing demand for inexpensive and safe anesthetics that can reduce fish stress caused by some procedures such as capture and handling. In this context, the present study evaluated the potential of essential oils (EO) of three Brazilian native plants (Hesperozygis ringens, Lippia sidoides and Ocotea acutifolia) as anesthetics for the silver catfish - Rhamdia quelen. Moreover, an analysis was made of the chemical composition of these oils and their influence on stress parameter. EO of H. ringens and O. acutifolia were effective as anesthetics, without behavioral side effects. EO of O. acutifolia (150 µL L-1) promoted an increase in blood glucose level. Regarding to the composition, pulegone accounts for 96.63% of the EO of H. ringens, and caryophyllene oxide amounts to 56.90% of the EO of O. acutifolia. Two chemotypes, thymol and carvacrol (68.40% and 67.89%, respectively) were verified for EO of L. sidoides. Both samples of EO of L. sidoides showed anesthetic activity in silver catfish, but exposure also caused loss of mucus and mortality. Thus, only the EO of H. ringens and O. acutifolia are advised for anesthetic use.

Existe uma crescente demanda por anestésicos baratos e seguros capazes de reduzir o estresse em peixes produzido durante procedimentos como captura e manuseio. Neste contexto, o presente estudo avaliou o potencial como anestésico dos óleos essenciais (EO) de três espécies vegetais nativas (Hesperozygis ringens, Lippia sidoides e Ocotea acutifolia) em jundiás - Rhamdia quelen. Adicionalmente, a composição química desses óleos e suas influências sobre o estresse também foram avaliadas. Os EO de H. ringens e O. acutifolia foram efetivos como anestésicos sem efeitos adversos detectáveis. EO de O. acutifolia (150 µL L-1) promoveu um aumento na glicemia. Em relação a sua composição, pulegona correspondeu a 96,63% do EO de H. ringens, e óxido de cariofileno a 56,90% do EO de O. acutifolia. Dois quimiotipos, timol e carvacrol (68,40% e 67,89%, respectivamente) foram verificados para os EO de L. sidoides. Ambas as amostras de EO de L. sidoides apresentaram atividade anestésica em jundiás, contudo a exposição produziu perda de muco e mortalidade. Desta forma, somente os EO de H. ringens e O. acutifolia têm seu uso recomendável como anestésicos.

Anesthesia and transport of fat snook centropomus parallelus with the essential oil of Nectandra megapotamica (Spreng) Mez

This study analyzed the chemical composition and anesthetic potential of essential oil (EO) of Nectandra megapotamica in fat snook (Centropomus parallelus). For the extraction of EO by hydrodistillation, leaves were separated in young (EO-Y) or old (EO-O), and the chemical composition of the EOs was determined by CG-MS. The anesthetic potential was assessed by the evaluation of induction and recovery time of anesthesia and stress response from anesthesia and transport. Three experiments were carried out: i) four different concentrations of each EO were tested to evaluate anesthesia induction and recovery time; ii) two concentrations of EO-O were tested for the evaluation of its effects on stress parameters (glucose, lactate, and Na+ and K+ plasma levels) caused by anesthesia; and iii) fish were transported in plastic bags, supplied with two concentrations of EO-O for the evaluation of water quality and mortality. All experiments were performed on fish acclimated to 0 and 33 ppt salinity. The main constituents of the Y and O-EOs were bicyclogermacrene (46.5/34.6%), α-pinene (26.8/26.2%), β-pinene (7.9/12.3%), and germacrene D (9.6/9.1%). Mild sedation was achieved at 30 °L L-1(1.3-3.2 min) and deep anesthesia at 150 °L L-1 (5.6-8.0 min) with both EOs. The recovery time ranged from 1-10 min. The EO-O was not able to avoid the stress of anesthesia evidenced by elevated glucose and lactate plasma levels observed in all groups. Plasma levels of Na+ and K+ were not significantly affected by treatments. During transport, the use of EO-O did not prevent deterioration in water quality and the post-transport mortality. In conclusion, the EO of N. megapotamica has anesthetic activity in fat snook, but it was not able to prevent the stress of anesthesia and transport.

Este estudo analisou a composição química e o potencial anestésico do óleo essencial (OE) de Nectandra megapotamica em robalos-peva (Centropomus parallelus). Para a extração do OE por hidrodestilação, as folhas foram separadas em jovens (OE-J) ou velhas (OE-V) e a composição química foi determinada por CG-EM. O potencial anestésico foi acessado através da avaliação do tempo de indução e recuperação da anestesia e resposta ao estresse do procedimento anestésico e transporte. Foram realizados três experimentos: em primeiro lugar, quatro concentrações diferentes de cada OE foram testadas para avaliar o tempo de indução à anestesia e de recuperação; em segundo lugar, duas concentrações do OE-V foram testadas para avaliar os efeitos sobre os parâmetros de estresse (níveis plasmáticos de glicose, lactato, Na+ e K+) causados pelo procedimento anestésico; em terceiro lugar, os peixes foram transportados em sacos plásticos com duas concentrações do OE-V para avaliação da qualidade da água e mortalidade. Todos os experimentos foram realizados em peixes aclimatados à salinidade zero e 33. Os constituintes majoritários do OE-J e OE-V foram: biciclogermacreno (46,5/34,6%), α-pineno (26,8/26,2%), β-pineno (7,9/12,3%) e germacreno D (9,6/9,1%). Sedação leve foi alcançada com 30 °L L-1(1,3-3,2 min) e anestesia profunda a partir de 150 °L L-1 (5,6-8,0 min) com ambos OEs. O tempo de recuperação variou entre 1-10 min.O OE-V não foi capaz de evitar o estresse do procedimento anestésico, evidenciado pelos elevados níveis plasmáticos de glicose e lactato observados em todos os grupos. Os níveis plasmáticos de Na+ e K+ não foram significativamente afetados pelos tratamentos. Durante o transporte, o OE-V não impediu a deterioração da qualidade da água e a mortalidade pós-transporte. Concluindo, o OE de Nectandra megapotamica apresenta atividade anestésica em robalos-peva, mas não foi capaz de evitar o estresse do procedimento anestésico e transporte.