, 1994) After its transportation, LPC is rapidly converted into

, 1994). After its transportation, LPC is rapidly converted into different products by specific routes which are important to regulate LPC levels on such tissues (Illingworth and Portman, 1972). However, the real content and the presence of LPC in cells or tissues are difficult to accurately determine (Schilling et al., 2004).

But, in vitro experiments showed that values above 50 μM, LPC is considered toxic, since plasma membrane integrity is disturbed due to its detergent-like feature ( Masamune et al., 2001). In fact, LPC is an intriguing molecule and should be more investigated. Data from literature point out the participation of PKC pathway in the retina ganglion cells leading them to survive (Santos and Araujo, 2000 and de Rezende Corrêa et al., 2005). PKC enzymes have been the primary mechanisms implicated in several biological effects, but the molecular basis for such activation SD-208 solubility dmso is poorly understood. So, the increased survival Adriamycin chemical structure of retinal ganglion cells induced by LM-PLA2-I as well as LPC showed to be dependent of PKC pathway since this effect was abolished in the presence of a PKC inhibitor (chelerythrine chloride). PKC comprises a family of serine/threonine kinases involved in different events of neuronal development, as proliferation, survival and apoptosis (Wooten, 1999). This family is divided into three groups; the conventional one (α, β,

γ) depends on calcium ion and is activated by diacylglycerol and phorbol ester; the atypical (ζ, λ) is calcium independent and is not activated by diacylglycerol or phorbol ester

while the novel class (δ, ɛ, η, θ) is also calcium independent, but it is activated by diacylglycerol or phorbol ester (Michie and Nakagawa, 2005 and Reyland, 2009). To evaluate the participation of classical PKC isoforms and calcium, BAPTA-AM was employed. As seen, the survival effect induced by LM-PLA2-I was not affected in the presence of BAPTA-AM. Thus, discarding the involvement of such group and the need of increase intracellular calcium levels on this trophic effect. These results, in part, are in contrast to Rigoni et al. (2007) and Montecucco and Rosseto (2008). They observed that the neurotoxic effect exhibited by taipoxin (a potent snake PLA2 neurotoxin isolated from Oxyuranus scutellatus) was dependent on the increase on intracellular calcium levels. However, we would like to emphasize all that our data are quite different from these authors’ results; because taipoxin displayed toxic effects on neurons and LM-PLA2-I had trophic or protective effects on neuronal ganglion cells. Rottlerin (a PKCδ isoform inhibitor) abolished the LM-PLA2-I-induced survival. However, rottlerin is not enough to state that the LPC-induced survival upon ganglion cells occurs through PKCδ pathway, but we might infer or postulate that this finding indicates a possible involvement of such enzyme to enhance on LPC-induced retinal ganglion survival effect.

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