Creatine Protects against Excitoxicity in an In Vitro Model of Neurodegeneration

Creatine has been shown to be neuroprotective in aging, neurodegenerative conditions and brain injury. As a common molecular background, oxidative stress and disturbed cellular energy homeostasis are key aspects in these conditions. Moreover, in a recent report we could demonstrate a life-enhancing and health-promoting potential of creatine in rodents, mainly due to its neuroprotective action. In order to investigate the underlying pharmacology mediating these mainly neuroprotective properties of creatine, cultured primary embryonal hippocampal and cortical cells were challenged with glutamate or H2O2. In good agreement with our in vivo data, creatine mediated a direct effect on the bioenergetic balance, leading to an enhanced cellular energy charge, thereby acting as a neuroprotectant. Moreover, creatine effectively antagonized the H2O2-induced ATP depletion and the excitotoxic response towards glutamate, while not directly acting as an antioxidant. Additionally, creatine mediated a direct inhibitory action on the NMDA receptor-mediated calcium response, which initiates the excitotoxic cascade. Even excessive concentrations of creatine had no neurotoxic effects, so that high-dose creatine supplementation as a health-promoting agent in specific pathological situations or as a primary prophylactic compound in risk populations seems feasible. In conclusion, we were able to demonstrate that the protective potential of creatine was primarily mediated by its impact on cellular energy metabolism and NMDA receptor function, along with reduced glutamate spillover, oxidative stress and subsequent excitotoxicity

A survey of ectoparasite infestation in dogs in Tehran, Iran Um levantamento da infestação de ectoparasitos em cães em Teerã, Irã

This survey was conducted to identify and estimate the frequencies of ectoparasites of dogs in Tehran, Iran. A total of 143 dogs attended at the Small Animal Hospital of the Veterinary School, the University of Tehran, were examined for the presence of ectoparasites and dermatological lesions. Ectoparasite specimens and blood samples were sent to parasitology and hematology laboratories, respectively. Ticks were the most frequent ectoparasite (36.4%, 52/143), followed by fleas (29.4%, 42/143), mites (25.9%, 37/143), and lice (8.4%, 12/143). Mixed infestations with two or more ectoparasites were detected in eight dogs. Rhipicephalus bursa was the most frequent ectoparasite in spring and summer. Ectoparasitic infestations were recorded mainly in large breeds and juvenile animals. Eosinophilia was more observed in dogs infested with Sarcoptes scabiei. The most common clinical sign, skin pruritus, was associated with mite and lice infestations. These results indicate that the tick R. bursa was the most prominent species of ectoparasite found in the evaluated group, followed by Ctenocephalides canis and S. scabiei var canis.<br>Esta pesquisa foi realizada para identificar e estimar a frequência de ectoparasitas de cães em Teerã, Irã. Um total de 143 cães, atendidos no Hospital de Pequenos Animais da Faculdade de Veterinária da Universidade de Teerã, foi examinado para a pesquisa de ectoparasitas e lesões cutâneas. Espécimes de ectoparasitos e amostras de sangue coletadas foram enviadas para exame em laboratório de parasitologia e hematologia, respectivamente. Os carrapatos foram os ectoparasitos mais frequentemente encontrados (36,4%, 52/143), seguidos por pulgas (29,4%, 42/143), sarnas (25,9%, 37/143) e piolhos (8,4%, 12/143). Infestações mistas com dois ou mais ectoparasitos foram observadas em oito cães. Rhipicephalus bursa foi o ectoparasito mais frequente na primavera e verão. Infestações de ectoparasitos foram registradas principalmente em raças maiores e animais jovens. Eosinofilia foi mais observado em cães infestados com Sarcoptes scabiei. O sinal clínico mais comum, prurido na pele, esteve associado às infestações por ácaros e piolhos. Estes resultados indicam o carrapato R. bursa como ectoparasito mais comum no grupo avaliado, seguido por Ctenocephalides canis e S. scabiei var canis