Changes in the lipid and fatty acid composition of hemolymph and ovaries during the reproductive cycle of Labidura riparia

Abstract

Lipid metabolism was investigated during the reproductive cycle of Labidura riparia (Pallas). The lipid classes and their constitutive fatty acids present in hemolymph and ovaries were measured using thin-layer chromatography and gas-liquid chromatography. In the hemolymph, total lipids increase steadily from the previtellogenic period to vitellogenic arrest. These lipids are predominantly diacylglycerols and phospholipids. In the ovaries, total lipids increase during vitellogenesis then decrease during the vitellogenesis arrest period. The major lipids are triacylglycerols, followed by phospholipids. In both hemolymph and ovaries, all lipid classes contained variable proportions of seven main fatty acids: the saturated fatty acids myristic acid (14:0), palmetic acid (16:0), and stearic acid (18:0); the monounsaturated fatty acids palmitoleic acid (16:1) and oleic acid (18:1); and the polyunsaturated fatty acids linoleic acid (18:2) and linolenic acid (18:3). Unsaturated fatty acids predominate throughout the reproductive cycle. The percentage compositions of total and triacylglycerol fatty acids do not change markedly during the reproductive cycle in hemolymph nor in ovaries, with 18:2, 18:1 and 16:0 fatty acids being the major components. However, for diacylglycerols and phospholipids, the proportions of fatty acids vary systematically. For phospholipids during the vitellogenesis period, 18:2 increases considerably whereas other fatty acids decrease; for diacylglycerols, these fatty acids vary in the reverse way.

OVARIAN NUTRITIONAL RESOURCES DURING THE REPRODUCTIVE CYCLE OF THE HEMATOPHAGOUSDIPETALOGASTER MAXIMA(HEMIPTERA: REDUVIIDAE): FOCUS ON LIPID METABOLISM

“…The increases of lipids, proteins, and/or glycogen from previtellogenesis to vitellogenesis were also reported in two vectors of Chagas’ disease (Santos et al., , ; Fruttero et al., ). In the Dermapteran Labidura riparia (Sayah, ), the profile of ovarian lipids varied during the reproductive cycle, similarly to that observed in D. maxima . On the other hand, it has been proposed that resources provisioned during vitellogenesis can be mobilized by oocyte resorption to either increase the lifespan of the female or secure its reproductive success (Bell and Bohm, ; Wang and Horng, ).…”

Lipid content of terrestrial arthropods in relation to body size, phylogeny, ontogeny and sex

“…Female arthropods often store proportionally more lipids than males (Zhou et al , 1995) because they use lipid to provision eggs. Ovarian and hemolymph lipid content in female Labidura riparia (Dermaptera) rises and falls in synchrony with cycles of vitellogenesis (Sayah, 2008), and increased lipid content of females compared with males is observed in Coccinella septempunctata (Coleoptera) over a range of geographic locations (Zhou et al , 1995) and in Ceratitis capitata (Diptera) over a range of diets (Nestel et al , 2005). It is thus expected that there would be sexual dimorphism in insect lipid content.…”

Sex makes them sleepy: host reproductive status induces diapause in a parasitoid population experiencing harsh winters

“…This finding is consistent with the metabolic phenotypes of the hosts, which revealed higher levels of sugar and sugar phosphate metabolites from the glycolytic pathway in oviparous females, this pathway providing elementary bricks for fatty acid and triacylglyceride (TAG) synthesis. Fatty acids serve as a main source of energy for physiological or ecological processes, including flight, gametes production, egg maturation and hormones synthesis (Arrese and Soulages 2010), and have been shown to represent up to 30% of aphids' fresh mass (Dillwith et al 1993, Sayah 2008. Interestingly, lipids can provide energy for overwintering insects and sugars can be metabolized to produce sugar-based cryoprotectant molecules (Storey and Storey 1991, Hahn and Denlinger 2011, Sinclair and Marshall 2018.…”