Retinoic acid as a survival factor in neuronal development of the grasshopper, Locusta migratoria

Abstract

Based on experience with cell cultures of adult insect neurons, we develop a serum-free culture system for embryonic locust neurons. Influences of trophic substances on survival and neurite outgrowth of developing neurons are investigated. For the first time, a positive trophic effect of 9-cis retinoic acid (9-cis RA) was shown in vitro on embryonic neurons of an insect. We observed longer cell survival of 50 % developmental stage neurons in cultures supplemented with 0.3 nM 9-cis RA. Furthermore, an influence on neuron morphology was revealed, as the addition of 9-cis RA to cell culture medium led to an increase in the number of neurites per cell. Although an RA receptor gene, LmRXR (Locusta migratoria retinoid X receptor), was expressed in the central nervous system throughout development, the influence of 9-cis RA on neuronal survival and outgrowth was restricted to 50 % stage embryonic cells.

Transcriptome Sequencing Reveals Potential Mechanisms of the Maternal Effect on Egg Diapause Induction of Locusta migratoria

“…These results suggested that RAI1 might inhibit diapause induction by repressing ROS and FOXO activities. On the other hand, retinoic acid has also been found to be critical for neurogenesis of L. migratoria [48]. Results in the present study suggested that other factors might inhibit induction of L. migratoria diapause under a long photoperiod.…”

Chronic exposure to imidacloprid or thiamethoxam neonicotinoid causes oxidative damages and alters carotenoid-retinoid levels in caged honey bees (Apis mellifera)

“…In fact, studies showed that unbalanced RA leads to developmental malformations in the tick ( Rhodnius prolixus ) 17 and Drosophila melanogaster 18 and influences metamorphosis and organogenesis in the firebug ( Pyrrhocoris apterus ), the red cotton stainer ( Decipifus cingulatus ) and the mealworm ( Tenebrio molitor ) 19 . Also, the 9- cis -RA isomer had a positive effect on cells isolated from Locusta migratoria and stimulated neurite outgrowth 20 . Retinoid metabolism has been shown to be sensitive to agrochemicals in fishes, frogs, birds and mammals (see review by Boily et al .…”

New Insights Into the Roles of Retinoic Acid Signaling in Nervous System Development and the Establishment of Neurotransmitter Systems

“…In crustaceans, multiple RXR isoforms are differentially expressed (Cui et al, 2013;Li et al, 2014), but it is not clear whether they can also transduce RA signals, which have so far only been shown to affect glucose metabolism and negatively interfere with limb regeneration in decapods (Hopkins and Durica, 1995;Sreenivasula Reddy and Srilatha, 2015). In insects, however, the presence of endogenous 9-cis RA and all-trans RA as well as their ability to directly activate RXR orthologs has been confirmed (Nowickyj et al, 2008) and a number of physiological responses to RA signals have been described, such as teratogenic effects on larval development (Nakamura et al, 2007) and the inhibition of metamorphosis (Němec et al, 1993), but also positive effects on cell survival and neurite outgrowth in cultures of embryonic locust neurons (Sukiban et al, 2014). Interestingly, RXR immunoreactivity was detected in both the cytoplasm and the neurites of specific neuronal subsets in the embryonic and adult CNS of the locust Locusta migratoria, hinting at a potential role for RA in insect neurogenesis and nervous system function (Bui-Göbbels et al, 2015;Sukiban et al, 2014).…”

“…In insects, however, the presence of endogenous 9-cis RA and all-trans RA as well as their ability to directly activate RXR orthologs has been confirmed (Nowickyj et al, 2008) and a number of physiological responses to RA signals have been described, such as teratogenic effects on larval development (Nakamura et al, 2007) and the inhibition of metamorphosis (Němec et al, 1993), but also positive effects on cell survival and neurite outgrowth in cultures of embryonic locust neurons (Sukiban et al, 2014). Interestingly, RXR immunoreactivity was detected in both the cytoplasm and the neurites of specific neuronal subsets in the embryonic and adult CNS of the locust Locusta migratoria, hinting at a potential role for RA in insect neurogenesis and nervous system function (Bui-Göbbels et al, 2015;Sukiban et al, 2014). Moreover, RA signals have been reported to regulate neurohormonal gene expression in response to tissue damage in the fruit fly Drosophila melanogaster, thus generating a developmental checkpoint for regeneration (Halme et al, 2010).…”