Schinus terebinthifolius Raddi: chemical composition, biological properties and toxicity / Schinus terebinthifolius Raddi: composição química, propriedades biológicas, e toxicidade

Schinus terebinthifolius Raddi is a medicinal plant known in Brazil as "aroeira da praia", which has been used in popular medicine as antipyretic, analgesic, depurative and in the treatment of diseases of the urogenital system. On the other hand, the scientific literature has reported that this plant has antimicrobial, anti-inflammatory and antiulcerogenic activity. This review addresses the main biological properties and toxicological effects of "aroeira da praia", in addition to a systematic approach of the compounds that were already found in this species, the great majority of which is present in the essential oils.

Schinus terebinthifolius Raddi é uma planta medicinal conhecida no Brasil como "aroeira da praia", utilizada na medicina popular como antitérmica, analgésica, depurativa e no tratamento de doenças do sistema urogenital. Por outro lado, a literatura científica relata que essa planta apresenta atividade antimicrobiana, anti-inflamatória, e antiulcerogênica. Essa revisão trata das principais propriedades biológicas e efeitos toxicológicos da aroeira da praia, além de uma abordagem sistemática acerca dos compostos que já foram encontrados nessa espécie, estando a maioria deles presente nos óleos essenciais.

Long-term administration of magnesium after acoustic trauma caused by gunshot noise in guinea pigs.

In a previous study we observed that a 7-day post-trauma magnesium treatment significantly reduced auditory threshold shifts measured 7 days after gunshot noise exposure. However this improvement was only temporary, suggesting that it could be potentially beneficial to prolong this treatment. The aim of the present study was to evaluate the efficacy of a long-term (1 month) magnesium treatment after an impulse noise trauma, in comparison with either a 7-day magnesium treatment, an administration of methylprednisolone (conventional treatment), or a placebo (NaCl). Guinea pigs were exposed to impulse noise (three blank gunshots, 170 dB SPL peak). They received one of the four treatments, 1 h after the noise exposure. Auditory function was explored by recording the auditory brainstem response (ABR) and measuring the distortion product otoacoustic emissions (DPOAE) over a 3-month recovery period after the gunshot exposure. The functional hearing study was supplemented by a histological analysis. The results showed that a 1-month treatment with magnesium was the most effective treatment in terms of hair cell preservation. The DPOAE confirmed this effectiveness. Methylprednisolone accelerated recovery but its final efficacy remained moderate. It is probable that magnesium acts on the later metabolic processes that occur after noise exposure. Multiple mechanisms could be involved: calcium antagonism, anti-ischaemic effect or NMDA channel blockage. Regardless of the specific mechanism, a 1-month treatment with magnesium clearly attenuates NIHL, and presents the advantage of being safe for use in humans.

Therapeutic efficacy of intra-cochlear administration of methylprednisolone after acoustic trauma caused by gunshot noise in guinea pigs.

The therapeutic efficacy of cochlear infusion of methylprednisolone (MP) after an impulse noise trauma (170dB SPL peak) was evaluated in guinea pigs. The compound action potential threshold shifts were measured over a 14 days recovery period after the gunshot exposure. For each animal, one of the cochlea was perfused directly into the scala tympani with MP during 7 days via a mini-osmotic pump, whereas the other cochlea was not pump-implanted. The functional study of hearing was supplemented by histological analysis. Forty eight hours after the trauma, significant differences between auditory threshold shifts in the implanted and non-implanted ears were observed for frequencies above 8kHz. At day 7, the difference was significant for only one frequency and no difference was observed after 14 days recovery. Cochleograms showed that the hair cell losses were significantly lower in the MP treated ears. This work indicates that direct infusion of MP into perilymphatic space accelerates hearing recovery, reduces hair cell losses after impulse noise trauma but does not limit permanent threshold shifts.

Spectrum of neural electrical activity in guinea pig cochlea: effects of anaesthesia regimen, body temperature and ambient noise.

Spectral analysis of electric noise recorded from the round window of the cochlea is thought to represent the summed spontaneous activity of the auditory nerve. It has been postulated that it could provide a possible tinnitus index. Because experimental conditions could change this neural activity, the effect of anaesthesia regimen, body temperature and ambient noise on the spectrum of spontaneous neural noise (SNN) were investigated in guinea pig cochlea. SNN was studied in awake guinea pigs and after anaesthesia with pentobarbital (P), xylazine/ketamine (XK) or xylazine/tiletamine-zolazepam (XTZ). Body temperature varied gradually from 33 to 41 degrees C under XK regimen. In awake animals, broadband noise was generated with intensity varying from 0 to 50 dB. The SNN consisted in a broad peak at approximately 900 Hz. With ambient broadband noise, it increased exponentially with the sound level with no shift in frequency. Soon after anaesthetic induction, the lowest frequencies were constantly decreased, and gradually the 900 Hz peak either increased moderately (P) or dropped steeply (XTZ) or remained unchanged (XK). Peak frequency increased linearly with body temperature whereas the amplitude reached a maximum at around 39.5 degrees C. In conclusion, these data indicate that experimental conditions such as anaesthesia regimen, body temperature and ambient noise modify the spontaneous neural outflow of the cochlea and must be taken into account when studying SNN.

Influência da temperatura de secagem e da concentração de Aerosil®200 nas características dos extratos secos por aspersão da Schinus terebinthifolius Raddi (Anacardiaceae) / Influence of the drying temperature and the Aerosil®200 concentration on the characteristics of Spray-dried extracts from Schinus terebinthifolius Raddi (Anarcadiaceae)

A Schinus terebinthifolius Raddi é muito usada na medicina popular e atualmente como fitomedicamento pelas propriedades antimicrobiana, cicatrizante e antiinflamatória. O objetivo deste trabalho foi avaliar a influência da temperatura de entrada e a concentração de Aerosil®200 nas características de extratos secos por aspersão da Schinus terebinthifolius Raddi. Os extratos preparados com etanol 70 °GL foram secos em Mini-spray dryer, Buchi B191, com adição do adjuvante tecnológico numa proporção de 20:80; 25:75 e 30:70 (p/p) Aerosil®200: resíduo seco, variando a temperatura de entrada de 120 °C a 160 °C. A umidade residual, o rendimento final do produto e o aumento da massa frente à umidade relativa controlada de 90 por cento foram usados como critério de avaliação. A análise de superfície de resposta revelou que à medida que a temperatura e a concentração de Aerosil aumentam, diminui a umidade residual dos extratos, bem como sua higroscopicidade. As melhores condições de secagem foram a temperatura de entrada de 140 °C e 30 por cento do adjuvante, resultando em rendimento acima de 80 por cento.

Schinus terebinthifolius Raddi has been used in the Brazilian folk medicine since a long time and now as phytopharmaceutical because of its antimicrobial, cicatrizant and anti-inflammatory properties. The aim of this work was to evaluate the influence of the inlet temperature and the Aerosil concentration on the characteristics of the spray-dried extracts from Schinus terebinthifolius Raddi by spray-drying method. The extracts were prepared from a 70 °GL ethanolic extract with a Buchi B 191 Mini-spray dryer with technological adjuvant into a ratio of 20:80; 25:75 and 30:70 (w/w) Aerosil®200: dried residue, in the inlet temperature range from 120 °C to 160 °C. The residual humidity, final yield and the moisture uptake profile at 90 percent Relative Humidity (RH) were used as evaluation criteria. The response surface analysis showed that increasing the temperature and the Aerosil®200 concentration, lead to lower residual humidity and moisture uptakes. The best drying parameters were the inlet temperature of 140 °C and 30 percent of Aerosil®200 concentration, resulting in yields over 80 percent.

Short-term diets enriched in stearic or palmitic acids do not alter plasma lipids, platelet aggregation or platelet activation status.

OBJECTIVE: To determine whether healthy males who consumed increased amounts of dietary stearic acid compared with increased dietary palmitic acid through the consumption of commercially available foods, exhibited any changes in plasma lipids, platelet aggregation or platelet activation status. DESIGN: A randomised cross-over dietary intervention. SUBJECTS AND INTERVENTIONS: Nine free-living healthy males consumed two experimental diets (stearic acid enriched, diet S, and palmitic acid enriched, diet P) for 3 weeks in a randomised cross-over design separated by a 3 week washout phase. The diets consisted of approximately 30% of energy as fat (30% of which was derived from the treatment diets) providing approximately 13 g/day as stearic acid and 17 g/day as palmitic acid on diet S and approximately 7 g/day as stearic acid and 22 g/day as palmitic acid on diet P. The dietary ratio of stearic to palmitic acids was 0.76 on diet S compared with 0.31 on diet P. Blood samples were collected on days 0 and 21 of each dietary period. RESULTS: LDL cholesterol levels and platelet aggregation response to the agonist ADP were significantly decreased (P<0.025) in subjects on diet S compared with day 0. Apart from that, there were no significant changes in plasma lipids, platelet aggregation, mean platelet volume and platelet reactivity between diets. There were no significant changes in stearic or palmitic acid levels in plasma phospholipid or triacylglycerol. There was a significant difference in palmitic acid levels in platelet phospholipids between the two diets. CONCLUSIONS: Use of commonly available foods led to a 27% increase in stearic acid (diet S) and a 19% increase in palmitic acid (diet P), on diets S and P respectively, and no significant differences between the two diets in plasma lipoprotein concentrations, platelet aggregation or platelet activation status.