Effects of Marine Phospholipids Extract on the Lipid Levels of Metastatic and Nonmetastatic Prostate Cancer Patients

Changes in phospholipid metabolism in exosomes of hormone-sensitive and hormone-resistant prostate cancer cells

Background: To explore the changes in lipids in exosomes of hormone-sensitive and hormone-resistant prostate cancer cells and develop an inexpensive and rapid technique for screening lipid-based biomarkers of prostate cancer.

Methods: Exosomes were extracted from LnCap, PC₃ and DU-145 cells, and their lipid composition was analyzed quantitatively using high-throughput mass spectrometry. Exosomes released by LnCap prostate cancer cells were also purified using a modified procedure based on polyethylene glycol (PEG) precipitation.

Results: Exosomes extracted from LnCap cells contained higher proportions of phosphatidyl choline, phosphatidyl ethanolamine and phosphatidyl inositol lipids than whole LnCap cells. Lysophosphatidylcholine, a harmful intermediate product of phosphatidylcholine metabolism in vivo, was not found in LnCap cells but in exosomes. Phospholipids were different in exosomes from LnCap, PC3 and DU-145 prostate cancer cells. The main lipid pathways involved, i.e., glycerophospholipid metabolism, autophagy, and ferroptosis pathways, were also different in these cells. Exosomes isolated by this modified PEG precipitation technique were similar in purity to those obtained using a commercial kit.

Conclusions: This study demonstrates that phosphatidylcholine and its harmful product lysophosphatidylcholine may play important roles in hormone-sensitive prostate cancer. Phospholipid exosome metabolism was changed in hormone-sensitive and hormone-resistant prostate cancer cells. The LPC, lipid pathway of autophagy and ferroptosis may act as therapeutic targets. The possibility of purifying prostate cancer cell exosomes using modified PEG precipitation is suitable for cancer screening.

Separation, identification and cardiovascular activities of phospholipid classes from the head of Penaeus vannamei by lipidomics and zebrafish models

Five phospholipid classes of Penaeus vannamei head were separated, analyzed and quantified. They had different cardiovascular activities evaluated in zebrafish models, which may provide a research basis for pharmaceutical use of marine phospholipids.

Fatty Acid Composition, Phospholipid Molecules, and Bioactivities of Lipids of the Mud Crab Scylla paramamosain

The mud crab increases the yield of farming in Southeast Asian countries. Scylla paramamosain, one of four mud crab species belonging to the Scylla genus, is a rich nutrient source during its soft-shell moulting period. In this study, we analysed the total lipid content, fatty acid components, and phospholipid molecular species of the S. paramamosain mud crab. The total lipid content was 1.62 ± 0.08%, which is similar to that of S. serrata previously reported. Twenty-one fatty acids were identified in S. paramamosain. The composition and molecular forms of the phospholipids were identified using high-performance liquid chromatography-high-resolution mass spectrometry. Fifty-four different molecules belonging to six types of phospholipids were identified. Notably, phospholipids were made of fatty acids with C16 : 0; C18 : 0; C20 : 4; C20 : 5; and C22 : 6 main components. The anti-inflammatory and cytotoxic effects of crab lipids and phospholipids were investigated for the first time. The anti-inflammatory activity of the total and polar lipids had IC50 values of 71.5 and 68.6 μg/mL, respectively. The crab polar lipid fraction, which contained phospholipids, also presented high cytotoxic activity toward five cancer cell lines with IC50 values ranging from 85.4 to 95.8 μg/mL.

In Vitro Antithrombotic Properties of Salmon (Salmo salar) Phospholipids in a Novel Food-Grade Extract

Marine and salmon polar lipids (PLs) extracted by conventional extractions with non-food-grade solvents (CE-salmon-PLs) possess antithrombotic bioactivities against platelet-activating factor (PAF) and thrombin. Similar effects of food-grade-extracted (FGE) marine PLs have not yet been reported. In this study, food-grade solvents were used to extract PLs from Irish organic farmed salmon (Salmo salar) fillets (FGE-salmon-PLs), while their antithrombotic bioactivities were assessed in human platelets induced by platelet aggregation agonists (PAF/thrombin). FGE-salmon-PLs were further separated by thin layer chromatography (TLC) into lipid subclasses, and the antithrombotic bioactivities of each subclass were also assessed. LC-MS was utilized to elucidate the structure-activity relationships. FGE-salmon-PLs strongly inhibited PAF-induced platelet aggregation, while their relevant anti-thrombin effects were at least three times more potent than the previously reported activities of CE-salmon-PLs. TLC-derived lipid fractions corresponding to phosphatidylcholines (PC) and phosphatidylethanolamines (PE) were the most bioactive lipid subclasses obtained, especially against thrombin. Their LC-MS analysis elucidated that they are diacyl- or alkyl-acyl- PC and PE moieties baring ω3 polyunsaturated fatty acids (PUFA) at their sn-2 position, such as eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA). Our results concerning the potent antithrombotic effects of FGE-salmon-PLs against both PAF and thrombin pathways strongly suggest that such food-grade extracts are putative candidates for the development of novel cardioprotective supplements and nutraceuticals.

[Importance of long chain omega-3 fatty acids in prostate cancer]

The benefits of long chain polyunsaturated omega-3 fatty acids (n-3 PUFA) from fish or administered as supplements remain controversial regarding prostate cancer (PCa). Based on the currently available evidence no clear benefit of n-3 PUFA intake to generally reduce PCa incidence has been found. On the other hand n-3 PUFAs have a clear influence on the development of already existing PCa. The intake of n-3-PUFAs considerably reduces the risk of metastasis and PCa-related mortality.