Attenuation of insulin signalling contributes to FSN‐1‐mediated regulation of synapse development

A neuronal F‐box protein FSN‐1 regulates Caenorhabditis elegans neuromuscular junction development by negatively regulating DLK‐mediated MAPK signalling. In the present study, we show that attenuation of insulin/IGF signalling also contributes to FSN‐1‐dependent synaptic development and function. The aberrant synapse morphology and synaptic transmission in fsn‐1 mutants are partially and specifically rescued by reducing insulin/IGF‐signalling activity in postsynaptic muscles, as well as by reducing the activity of EGL‐3, a prohormone convertase that processes agonistic insulin/IGF ligands INS‐4 and INS‐6, in neurons. FSN‐1 interacts with, and potentiates the ubiquitination of EGL‐3 in vitro, and reduces the EGL‐3 level in vivo. We propose that FSN‐1 may negatively regulate insulin/IGF signalling, in part, through EGL‐3‐dependent insulin‐like ligand processing.     

The natural place to begin: The ethnoprimatology of the Waorani

Ethnoprimatology is an important and growing discipline, studying the diverse relationships between humans and primates. However there is a danger that too great a focus on primates as important to humans may obscure the importance of other animal groups to local people. The Waorani of Amazonian Ecuador were described by Sponsel [Sponsel (1997) New World Primates: Ecology, evolution and behavior. New York: Aldine de Gruyter. p 143–165] as the “natural place” for ethnoprimatology, because of their close relationship to primates, including primates forming a substantial part of their diet. Therefore they are an ideal group in which to examine contemporary perceptions of primates in comparison to other types of animal. We examine how Waorani living in Yasuní National Park name and categorize primates and other common mammals. Although there is some evidence that the Waorani consider primates a unique group, the non‐primate kinkajou and olingo are also included as part of the group “monkeys,” and no evidence was found that primates were more important than other mammals to Waorani culture. Instead, a small number of key species, in particular the woolly monkey (Lagothrix poeppigii) and white‐lipped peccary (Tayassu pecari), were found to be both important in the diet and highly culturally salient. These results have implications for both ethnoprimatologists and those working with local communities towards broader conservation goals. Firstly, researchers should ensure that they and local communities are referring to the same animals when they use broad terms such as “monkey,” and secondly the results caution ethnoprimatologists against imposing western taxonomic groups on indigenous peoples, rather than allowing them to define themselves which species are important. Am. J. Primatol. 75:1117–1128, 2013. © 2013 The Authors. American Journal of Primatology Published by Wiley Periodicals, Inc.     

Antioxidant and Neuroprotective Effects of Scrophularia striata Extract Against Oxidative Stress-Induced Neurotoxicity

In this study, the neuroprotective effect of Scrophularia striata Boiss (Scrophulariaceae) extract, a plant growing in northeastern of Iran, against oxidative stress-induced neurocytotoxicity in PC12 was evaluated. The PC12 cell line pretreated with different concentrations (10, 50, 100, and 200 μg/ml) of the extract and then treated with H₂O₂ to induce oxidative stress and neurotoxicity. Survival of the cells, reactive oxygen species (ROS) generation, and apoptosis were measured using MTT assay, fluorescent probe 2′,7′-dichlorofluorescein diacetate, and annexin V/propidium iodide, respectively. Moreover, the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) was used to evaluate the antioxidant capacity of the plant extract. Phytochemical assay by thin layer chromatography showed that the main components, including phenolic compounds, phenyl propanoids and flavonoids, were presented in the S. striata extract. The extract in concentrations of 50–200 μg/ml protected PC12 cells from H₂O₂-induced toxicity. The survival of the cells at concentration of 200 μg/ml was 64 % compared to that of H₂O₂ alone-treated cells (48 %) (p < 0.001). The extract also dose-dependently reduced intracellular ROS production (p < 0.001). Moreover, the extract showed antioxidative effects and decreased apoptotic cells. Collectively, these findings indicated the ability of S. striata to decrease ROS generation and cell apoptosis and also suggest the presence of the neuroprotective agents in this plant.