Alberto Olivares

Acute oral toxicity and anti-inflammatory activity of hydroalcoholic extract from Lampaya medicinalis Phil in rats

BackgroundAlgesia and inflammation are related with several pathological conditions. It is known that many drugs available for the treatment of these problems cause unwanted side effects. This study was aimed at evaluating acute toxicity and anti-inflammatory activity of Lampaya medicinalis Phil. (Verbenaceae) widely used in the folk medicine of Northern Chile against rheumatism, arthritis and body joints pain.ResultsOral administration of hydroalcoholic extract (HAE) at the highest dose of 3000 mg/ Kg body weight resulted in no mortalities or evidence of significant behavioral changes. Histological examination revealed normal architecture and no significant adverse effects were observed on the liver, kidney, heart, lung or ovaries and testicles. The results suggest that the oral administration of hydroalcoholic extract (HAE) from Lampaya medicinalis did not produce any toxic effect in rats. Hydroalcoholic extract (HAE) significantly inhibited the carrageenan-induced rat paw edema in dose – response relationship, at test doses of 37.5, 75, 150 and 300 mg/Kg body weight. Maximum inhibition (61.98 ± 2.69%) was noted at 300 mg/Kg after 2 h of drug treatment carrageenan induced paw edema, whereas indomethacin produced 47.90 ± 1.16% of inhibition. The inhibitory values of edema at 3 h postcarrageenan were 31.04±0.75%, 40.51 ± 2.36%, 48.97 ± 1.14% and 56.87 ± 0.41% for 37.5, 75, 150, and 300 mg/kg of extract respectively. Indomethacin (10 mg/Kg) gave a percentage inhibition of 49.44 ± 1.44. HAE (300 and 150 mg/kg) induced an anti-inflammatory effect greater than (or comparable) with the effect of indomethacin from 2nd to 4th hours of the experiment.ConclusionsOur results reveal for first time that compounds contained in the hydroalcoholic extract of Lampaya medicinalis Phil exert anti-inflammatory effect and the oral administration is safe and non toxic up to dose level 3000 mg/kg body weight. The anti-inflammatory activity may be associated with the presence of flavonoids. These findings also justify the traditional use of the plant for treating pain.

Temperature modulates spatio-temporal variability of the functional reproductive maturation of Octopus maya (Cephalopoda) on the shelf of the Yucatan Peninsula, Mexico

Laboratory studies have demonstrated that high temperatures inhibit spawning of Octopus maya; therefore, in oceanic warming scenarios the population dynamics may be affected. The aim of the present study was to go beyond laboratory studies under controlled temperatures to examine the possible relationship between large-scale thermal patterns and reproductive season (represented by functional maturation) of O. maya in the wild on the continental shelf of the Yucatan Peninsula, where it is endemic. The macroscopic maturity index (MaMI) was obtained in females, and reproductive complex index (RCI) and number of spermatophores in males. Associations between these indices and environmental temperature regime were inferred by sampling octopuses in an upwelling zone (Z-I), a transition zone (Z-II) and a nonupwelling zone (Z-III). The reproductive condition of O. maya differed between Z-I and Z-III. In all zones, the proportion of adults showing functional maturity was highest in both females (MaMI: 36–71% of values ≤0.2) and males (RCI: 12–40% of values ≥0.9; 41–49 spermatophores per octopus) during the season of winter storms (‘nortes’ season, November–February), when the sea-surface temperature oscillates around 25 °C. In Z-I, some individuals were functionally mature throughout the year, likely due to low temperatures maintained by summer upwelling. Zone-I had the greatest proportion of functionally mature males (up to 40% of adults in ‘nortes’ season) and the greatest number of spermatophores (mean 43–49 spermatophores per octopus in all seasons). Females in Z-III (without upwelling) were functionally mature mainly in the ‘nortes’ season when water temperature decreased, with only a small proportion mature in the rest of the year when water temperatures reached 31 °C. As predicted by laboratory studies, water temperature below 27 °C appears to be favourable for the functional reproductive maturation of wild O. maya.

Digestive Physiology of Octopus maya and O. mimus: Temporality of Digestion and Assimilation Processes

Digestive physiology is one of the bottlenecks of octopus aquaculture. Although, there are successful experimentally formulated feeds, knowledge of the digestive physiology of cephalopods is fragmented, and focused mainly on Octopus vulgaris. Considering that the digestive physiology could vary in tropical and sub-tropical species through temperature modulations of the digestive dynamics and nutritional requirements of different organisms, the present review was focused on the digestive physiology timing of Octopus maya and Octopus mimus, two promising aquaculture species living in tropical (22–30°C) and sub-tropical (15–24°C) ecosystems, respectively. We provide a detailed description of how soluble and complex nutrients are digested, absorbed, and assimilated in these species, describing the digestive process and providing insight into how the environment can modulate the digestion and final use of nutrients for these and presumably other octopus species. To date, research on these octopus species has demonstrated that soluble protein and other nutrients flow through the digestive tract to the digestive gland in a similar manner in both species. However, differences in the use of nutrients were noted: in O. mimus, lipids were mobilized faster than protein, while in O. maya, the inverse process was observed, suggesting that lipid mobilization in species that live in relatively colder environments occurs differently to those in tropical ecosystems. Those differences are related to the particular adaptations of animals to their habitat, and indicate that this knowledge is important when formulating feed for octopus species.

Octopus mimus (MOLLUSCA: CEPHALOPODA) EMBRYO MISDEVELOPMENT DUE TO CHRONIC EXPOSURE TO THE ORGANOSPHOSPHORUS PESTICICE PARATHON

Los pesticidas son de amplio uso mundial. Actualmente hay gran preocupacion por la contaminacion marina con estas sustancias. El desarrollo de los organismos acuaticos esta especialmente comprometido. Por esta razon, se estudio el desarrollo temprano de embriones de Octopus mimus expuestos a Parathion comercial. Se encontro que concentraciones sobre 0.4 mM del pesticida alteran la formacion del disco embrionario al estado de blastula resultando en una gastrulacion anormal y detencion posterior del desarrollo. Este efecto toxico puede ser debido al bloqueo de la sintesis de ADN resultando en una disminucion del numero de celulas blastodermicas al momento de la epibolia, y por tanto impiden el inicio de la invaginacion. De esta manera, la contaminacion marina parece ser de importancia para la sobrevida de las especies acuaticas expuestas a ella

Sexual maturation and embryonic development in octopus: use of energy and antioxidant defense mechanisms using Octopus mimus as a model.

Sexual maturation and reproduction influence the status of a number of physiological processes and consequently the ecology and behaviour of cephalopods. Using Octopus mimus as study model, the present study was focused in the changes in biochemical composition that take place during gonadal maturation of octopus females and its consequences in embryo and hatchlings characteristics, putting special attention to energetic metabolites, digestive enzymes and antioxidant defence mechanisms. To do that, a total of 32 adult females of Octopus mimus were sampled during ovarian maturation and the biochemical composition (metabolites and digestive enzymes) of digestive gland (DG) and ovaries (only metabolites) were followed during physiological and functional maturation. Levels of protein (Prot), triacyl glycerol (TG), cholesterol (Chol), glucose (Glu) and glycogen (Gly) were evaluated. In DG also the activity of alkaline and acidic enzymes was measured. Simultaneously, groups of eggs coming form mature females were also sampled along development, and metabolites (Prot, TG, Glu, Gly, TG, Chol), digestive enzymes activity (Lipases, alkaline and acidic), antioxidant defence mechanisms and radical oxygen species (ROS) were evaluated. Results obtained showed that ovarium is a site for reserve of some nutrients for reproduction. Presumably, TG where stored at the beginning of the maturation processes followed by Chol, both at the same time were energetically supported by Glu, derived from Gly following gluconeogenic pathways. Also, was observed that embryos during organogenesis nutrients and enzymes (metabolic, digestive and REDOX system) where maintained without significant changes and in a low activity. Results obtained in the present study shows that that activity could be not energetically costly. In contrast, was observed that during the embryo growth there were mobilization of nutrients and activation of the metabolic and digestive enzymes, joint with increments in consumption of yolk and glycogen, and reduction in molecules associated with oxidative stress, allowing paralarvae hatch with the antioxidant defence mechanisms ready to support the ROS production.

Effects of inter-annual temperature variability, including ENSO and post-ENSO events, on reproductive traits in the tunicate Pyura praeputialis

ABSTRACT Reproduction in tunicates is considered to be particularly vulnerable to changes in seawater temperature. In the present study we investigated the effects of sea surface temperature and temperature anomalies on reproductive traits of the non-native sessile tunicate Pyura praeputialis. Reproductive traits of this species were investigated over the course of 67 months, based on samples collected at two localities (eastern and western shorelines) of the Bay of Antofagasta. The study period included years with different oceanic and atmospheric conditions: a warm event, El Niño (June 1997 to July 1998); a cold event, La Niña (August 1998 to December 2000); and post-La Niña (January 2000 to December 2002). We compared two common indices (condition and gonadosomatic) and histological sections to evaluate the maximum reproduction index of this introduced species that dominates a large part of the rocky intertidal habitat in the Bay of Antofagasta. We found sexually mature individuals all year-round and a decrease in both reproductive indices matching the reduction in the sea surface temperature during the austral autumn and winter months. The results suggest that gonad development in this species is sensitive to sea surface temperature and thermal anomalies. We conclude that future thermal anomalies or projected global average sea surface warming associated with climate change might have no negative consequences on these reproductive traits of P. praeputialis. This suggests this species is ecologically resilient and that the ecosystem services that this species provides for other invertebrate and algal species will be maintained.

Oviducal glands throughout the gonad development stages: a case study of Octopus mimus (Cephalopoda)

ABSTRACT The oviducal glands (ODG) play a crucial role in octopus reproduction. Herein, structural changes of each section of the ODG of Octopus mimus are described histologically throughout the gonad development stages (GDS). To do this, the epithelial height, stereociliated or non-stereociliated epithelium, nucleus type (pycnotic or non-pycnotic), epithelial secretions and the value range of the macroscopic maturity index (MaMI), which directly involves ODG status, were measured. The ODG are internally constituted of two glandular units (central and peripheral glands) and one set of receptacles (the spermathecae). High epithelia (40 to 80 μm) were observed in both gland units during periods with low MaMI values (< 0.1) corresponding to III-mature and IV-pre-spawning. The stereociliated epithelium was only apparent in II-maturing and III-mature in both gland units. The nuclei were noticeably pycnotic in the central gland during III-mature, IV-pre-spawning and V-spawning, but pycnotic in the peripheral gland only during VI-depletion. The epithelium was disorganised during VI-depletion, while sulphated acid mucin was only present during III-mature in the central gland. The epithelium transformations during the GDS are related to the functions of the gland units and to their multiple secretions. The ODG histology complements the GDS and provides better reproductive status assessment.

Parámetros reproductivos y poblacionales de Thais chocolata (Duclos, 1832) (Gastropoda, Thaididae), en la reserva marina La Rinconada, Antofagasta, Chile

Reproductive and population parameters of Thais chocolata that would contribute to the validation of the current extraction standards were obtained by performing a study in the protected area of La Rinconada Marine Reserve, Antofagasta, Chile, from December 2008 to January 2010. In terms of reproduction, the results revealed asynchronic gonad development in the population, with specimens in different stages of maturity throughout the year. Mature individuals were distributed between 5 and 13 m depth, forming aggregations at 5 m depth during much of the year. Periods of greater maturity were observed from July to August and November to January, with the most important aggregations at the end of both periods. A relationship was observed between the months with the greatest maturity and aggregations and the months with the highest daily temperature fluctuations. At the population level, the results allowed us to estimate 2.3*10 6 individuals, with 39% of this population over the minimum legal size (55 mm). The relatively slow growth estimated for this population was probably influenced by the high variability of the bottom temperature in this area. The critical size and size at first maturity of the population were higher than the minimal legal size, making it is necessary to review the current fishing regulation for this species. The effectiveness of the State marine reserves in the conservation of this marine resource was demonstrated.