No abstract

At present, there is a growing interest in the study of the neurotropic activity of polyunsaturated fatty acids ethanolamides (N-acylethanolamines). N-docosahexaenoylethanolamine (DHEA, synaptamide) is an endogenous metabolite and structural analogue of anandamide, a widely studied endocannabinoid derived from arachidonic acid. The results of this study demonstrate that DHEA, when administered subcutaneously (10 mg/kg/day, 7 days), promotes cognitive recovery in rats subjected to mild traumatic brain injury (mTBI). In the cerebral cortex of experimental animals, we analyzed the dynamics of Iba-1-positive microglia activity changes and the expression of pro-inflammatory markers (IL1β, IL6, CD86). We used immortalized mouse microglial cells (SIM-A9) to assess the effects of DHEA on LPS-induced cytokines/ROS/NO/nitrite, as well as on CD206 (anti-inflammatory microglia) and the antioxidant enzyme superoxide dismutase (SOD) production. In vivo and in vitro experiments showed that DHEA: (1) improves indicators of anxiety and long-term memory; (2) inhibits the pro-inflammatory microglial cells activity; (3) decrease the level of pro-inflammatory cytokines/ROS/NO/nitrites; (4) increase CD206 and SOD production. In general, the results of this study indicate that DHEA has a complex effect on the neuroinflammation processes, which indicates its high therapeutic potential.

Biological active compounds, 1-O-alkyl-sn-glycerols (AG), were isolated from liver oil of the squid Berryteuthis magister. The main components of the initial lipids were 1-O-alkyl-2,3-diacyl-sn-glycerols (38.50 %) and triacylglycerols (24.26 %). The first step of separation was the alkaline hydrolysis of oil to form a lipid mixture consisting of AG, free fatty acids and cholesterol. AG were separated by double recrystallization from acetone at -20 °C and 1 °C. A simple procedure is proposed for obtaining AG with a purity of 99.22 %, the main component of which is chimyl alcohol (94.39 %). Purity and structure of the obtained products were confirmed by GC and GC-MS technique. Isolated AG may be used in nutrition and cosmetics.

One of the ways to reduce age‐related changes can be a diet correction by adding biologically active substances. We studied the effect of a diet including alkyl glycerol ethers (AGs) and n‐3 polyunsaturated fatty acid (PUFA) concentrate isolated from the hepatopancreas of Berrytheuthis magister squid on hematological parameters and plasmalogens level in the liver of elderly rats. The senile animals showed decrease in hemoglobin, a three‐fold decrease in leukocytes, a three‐fold increase in platelet count, and a double decrease of blood coagulation time in the peripheral blood. Age‐related changes in rats were characterized by the development of anemia, hypercoagulation, and a decrease in the number of immunocompetent cells. AGs, both separately and in combination with n‐3 PUFAs, induced an increase in the number of red blood cells and hemoglobin, a decrease in the number of platelets, and an immunostimulating activity. Under the action of AGs and n‐3 PUFAs, the concentration of plasmalogens and docosahexaenoic acid in the rat liver increased 2‐ and 1.5 folds, respectively. Practical Application This study showed that the combined use of AGs and n‐3 PUFAs improves the rheological properties of the blood and the state of the immune system during aging. The enrichment of diet with dietary supplements, whose structure contains AGs and n‐3 PUFAs can increase the content of plasmalogens in the body.

1‐O‐alkylglycerols (AKG) are a class of natural ether lipids derived from 1‐O‐alkyl‐2,3‐diacyl‐sn‐glycerols by deacylation. In this study, 1‐O‐alkylglycerol (AKG) composition was investigated in the hepatopancreas lipids of the crab Paralithodes camtschaticus and the liver lipids of the squid Berryteuthis magister and the skate  Bathyraja parmifera. One of the principal AKG in marine organisms was 1‐O‐hexadecyl‐sn‐glycerol (AKG 16:0). To assess AKG influence on melanoma, we evaluated the cytotoxicity and antiproliferative actions of natural AKG 16:0 and synthetic 1‐O‐octyl‐sn‐glycerol (AKG 8:0) on three human melanoma cell lines SK‐Mel‐5, SK‐Mel‐28, and RPMI‐7951. Natural AKG 16:0 in concentration up to 20 µM was not toxic to all cell lines. AKG 8:0 showed no toxicity to cells SK‐Mel‐5 and SK‐Mel‐28 in concentrations up to 20 µM but had moderate cytotoxicity to RPMI‐7951 cells with an IC50 of 13 µM. Both investigated substances inhibited the proliferation, formation, and growth of cell colonies of RPMI‐7951. Practical applications AKG exhibit a variety of biological activities, including anticancer effects. In this study, the liver lipids of the skate B. parmifera and the hepatopancreas lipids of crab P. camtschaticus were shown to be sources of AKG. Our data showed that AKG can be used to prevent the formation of new colonies of malignant cells in combination therapy against melanoma. The results will be useful for future studies involving marine ether lipids and the examination of their anticancer properties against malignant cells.