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Start Over Subject diacylglycerol

1. Analysis of the lipids mobilized by adipokinetic hormones in the firebug Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae)

Creator:
Bártů, Iva, Tomčala, Aleš, Socha , Radomír, Šimek , Petr, and Kodrík, Dalibor
Type:
article, model:article, and TEXT
Subject:
Heteroptera, Pyrrhocoris apterus, AKH, Lipid, triacylglycerol, diacylglycerol, fatty acid, haemolymph, fat body, linden seed, HPLC, ESI-MS, and mass spectrometry
Language:
English
Description:
Effects of two adipokinetic hormones (Pyrap-AKH and Peram-CAH-II) on the presence of diacylglycerol (DG) molecular species and their fatty acid (FA) constituents in the haemolymph of the firebug Pyrrhocoris apterus were investigated using liquid chromatography (HPLC) and electrospray ionization mass spectrometry (ESI-MS). The results show that DGs with characteristic FAs are preferentially mobilized from the fat body (FB) by the action of both the AKHs produced by P. apterus. Both the macropterous and brachypterous morphs have similar DG and FA profiles. A difference in the action of the Pyrap-AKH and the Peram-CAH-II, however, results in distinct differences in the distribution of FAs in the macropterous morph. It seems that C16 to a slight extent and unsaturated C18 FAs mainly play a dominant role in the AKH based action, in particular linoleic acid (18:2), which represents 50-60% of the total DG mobilized. The metabolically active C16 and C18 FAs are preferentially absorbed from the linden seeds and accumulated in the FB. The relationships between AKH action and FA distribution in DGs in P. apterus, compared to other insect species are summarized and discussed in detail.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

2. Involvement of phospholipids in the mechanism of insulin action in HEPG2 cells

Creator:
Novotná, R., De Vito, P., Currado, L., Luly, P., and Baldini, P. M.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, inzulin, insulin, phosphatidic acid, diacylglycerol, phospholipases, HEPG2 cells, 14, and 612
Language:
English
Description:
The mechanism of action by which insulin increases phosphatidic acid (PA) and diacylglycerol (DAG) levels was investigated in cultured hepatoma cells (HEPG2). Insulin stimulated phosphatidylcholine (PC) and phosphatidyl-inositol (PI) degradation through the activation of specific phospholipases C (PLC). The DAG increase appears to be biphasic. The early DAG production seems to be due to PI breakdown, probably through phosphatidyl-inositol-3-kinase (PI3K) involvement, whereas the delayed DAG increase is derived directly from the PC-PLC activity. The absence of phospholipase D (PLD) involvement was confirmed by the lack of PC-derived phosphatidylethanol production. Experiments performed in the presence of R59022, an inhibitor of DAG-kinase, indicated that PA release is the result of the DAG-kinase activity on the DAG produced in the early phase of insulin action., R. Novotná, P. de Vito, L. Currado, P. Luly, P. M. Baldini., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public