Progression of Postprandial Blood Plasma Phospholipids Following Acute Intake of Different Dairy Matrices: A Randomized Crossover Trial

Studies have indicated that the dairy matrix can affect postprandial responses of dairy products, but little is known about the effect on postprandial plasma phospholipid levels. This study investigated postprandial plasma phospholipid levels following consumption of four different dairy products that are similar in micro and macro nutrients, but different in texture and structure: cheddar cheese (Cheese), homogenized cheddar cheese (Hom. Cheese), micellar casein isolate with cream (MCI Drink) or a gel made from the MCI Drink (MCI Gel). The study was an acute randomized, crossover trial in human volunteers with four test days. Blood samples were collected during an 8 h postprandial period and the content of 53 plasma phospholipids was analysed using liquid chromatography-mass spectrometry (LC-MS). No meal–time interactions were revealed; however, for nine of the 53 phospholipids, a meal effect was found. Thus, the results indicated a lower plasma level of specific lyso-phosphatidylethanolamines (LPEs) and lyso-phosphatidylcholines (LPCs) following consumption of the MCI Gel compared to the MCI Drink and Hom. Cheese, which might be attributed to an effect of viscosity. However, further studies are needed in order to reveal more details on the effect of the dairy matrix on postprandial phospholipids.

Association of Plasma Phospholipids with Age-Related Cognitive Impairment: Results from a Cross-Sectional Study

Decreased concentration of phospholipids were observed in brain tissue from individuals with dementia compared with controls, indicating phospholipids might be a key variable in development of age-related cognitive impairment. The reflection of these phospholipid changes in blood might provide both reference for diagnosis/monitoring and potential targets for intervention through peripheral circulation. Using a full-scale targeted phospholipidomic approach, 229 molecular species of plasma phospholipid were identified and quantified among 626 senile residents; the association of plasma phospholipids with MoCA score was also comprehensively discussed. Significant association was confirmed between phospholipid matrix and MoCA score by a distance-based linear model. Additionally, the network analysis further observed that two modules containing PEs were positively associated with MoCA score, and one module containing LPLs had a trend of negative correlation with MoCA score. Furthermore, 23 phospholipid molecular species were found to be significantly associated with MoCA score independent of fasting glucose, lipidemia, lipoproteins, inflammatory variables and homocysteine. Thus, the decreased levels of pPEs containing LC-PUFA and the augmented levels of LPLs were the most prominent plasma phospholipid changes correlated with the cognitive decline, while alterations in plasma PC, PS and SM levels accompanying cognitive decline might be due to variation of lipidemia and inflammatory levels.

Is There a FADS2-Modulated Link between Long-Chain Polyunsaturated Fatty Acids in Plasma Phospholipids and Polyphenol Intake in Adult Subjects Who Are Overweight?

Dietary polyphenols promote cardiometabolic health and are linked with long-chain polyunsaturated fatty acids in plasma phospholipids (LC-PUFA). The FADS2 polymorphisms are associated with LC-PUFA metabolism and overweight/obesity. This 4-week study examined the link between polyphenol intake, FADS2 variants (rs174593, rs174616, rs174576) and obesity in 62 overweight adults (BMI ≥ 25), allocated to consume 100 mL daily of either: Aronia juice, a rich source of polyphenols, with 1177.11 mg polyphenols (expressed as gallic acid equivalents)/100 mL (AJ, n = 22), Aronia juice with 294.28 mg polyphenols/100 mL (MJ, n = 20), or nutritionally matched polyphenol-lacking placebo as a control (PLB, n = 20). We analyzed LC-PUFA (% of total pool) by gas chromatography and FADS2 variants by real-time PCR. Four-week changes in LC-PUFA, BMI, and body weight were included in statistical models, controlling for gender and PUFA intake. Only upon AJ and MJ, the presence of FADS2 variant alleles affected changes in linoleic, arachidonic, and eicosapentaenoic acid (EPA). Upon MJ treatment, changes in EPA were inversely linked with changes in BMI (β= −0.73, p = 0.029) and weight gain (β= −2.17, p = 0.024). Only in subjects drinking AJ, the link between changes in EPA and anthropometric indices was modified by the rs174576 variant allele. Our results indicate the interaction between FADS2, fatty acid metabolism, and polyphenol intake in overweight subjects.

Plasma Phospholipids: A Promising Simple Biochemical Parameter to Evaluate COVID-19 Infection Severity

Background: Coronavirus-19 (COVID-19) pandemic is a worldwide public health problem that has been known in China since December 25, 2019. Phospholipids are structural components of the mammalian cytoskeleton and cell membranes. They suppress viral attachment to the plasma membrane and subsequent replication in lung cells. In the virus-infected lung, phospholipids are highly prone to oxidation by reactive oxygen species, leading to the production of oxidized phospholipids (OxPLs). Objective: This study was carried out to explain the correlation between the level of plasma phospholipids in patients with COVID-19 infection and the levels of cytokine storms to assess the severity of the disease. Methods: Plasma samples from 34 enrolled patients with mild, moderate, and severe COVID-19 infection were collected. Complete blood count (CBC), plasma levels of D-dimer, ferritin, C-reactive protein (CRP), cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), phospholipids, secretory phospholipase A2 (sPLA2)α2, and cytokine storms were estimated, and lung computed tomography (CT) imaging was detected. Results: The CBC picture showed the presence of leukopenia, lymphopenia, and eosinopenia in patients with COVID-19 infection. Furthermore, a significant increase was found in plasma levels of D-dimer, CRP, ferritin, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-13 as well as sPLA2α2 activity compared to normal persons. However, plasma levels of phospholipids decreased in patients with moderate and severe COVID-19 infection, as well as significantly decreased in levels of triacylglycerols and HDL-C in plasma from patients with severe infection only, compared to normal persons. Furthermore, a lung CT scan showed the presence of inflammation in a patient with mild, moderate, and severe COVID-19 infection. Conclusions: This study shows that there is a correlation between plasma phospholipid depletion and elevated cytokine storm in patients with COVID-19 infection. Depletion of plasma phospholipid levels in patients with COVID-19 infection is due to oxidative stress, induction of cytokine storm, and systemic inflammatory response after endothelial cell damage promote coagulation. According to current knowledge, patients with COVID-19 infection may need to administer surfactant replacement therapy and sPLA2 inhibitors to treat respiratory distress syndrome, which helps them to maintain the interconnected surfactant structures.

Abstract 155: Identification of Decreased Plasma Lysophosphatidylcholine Using Phospholipidomics in Cardiac Arrest: A Novel Therapeutic Application

Introduction: Cardiac arrest (CA) is a significant public health burden with few effective therapies available. Plasma phospholipids are important for proper organ function. We hypothesized that alterations in plasma phospholipids may play an important role in the pathophysiology of CA and normalizing these alterations may be a novel therapeutic application for the treatment of CA. Objective: The aim of this study was to test the phospholipid therapy as a novel therapeutic approach in CA. Methods and Results: We performed phospholipidomics on plasma samples from CA patients and controls from North Shore University Hospital to identify plasma phospholipids that correlate with injury severity. We then confirmed the finding using our rat model of 10 and 14 min of asphyxia-induced CA. Finally, we tested the effect of administering LPC using the same model. From the phospholipids analyzed, lysophosphatidylcholine (LPC) levels were found to be the most significantly decreased in CA patients, which was also associated with survival of patients. The same trend was observed in the rat model where rats after 14 min CA had significantly lower plasma LPC levels than rats after 10 min CA. We also found that LPC levels began to decrease continuously following resuscitation, but not during the ischemic phase of CA. Finally, we found that LPC administration substantially increased rat survival compared to the control group. Rats who survived in the LPC-treated group displayed significantly improved brain function and the neuroprotective effect of LPC is supported by improved brain histology. We also found LPC treatment increased plasma IL-10 levels and decreased IL-6 levels post-CA. Conclusion: Plasma LPC levels inversely correlated with survival and LPC treatment significantly improved brain function and rat survival. This data indicates that the decrease of plasma LPC is a major mechanism responsible for brain damage demonstrating the potential of LPC as a novel therapeutic in CA.

Metabolically healthy obesity: Is there a link with PUFA intake and status?

The aim of this study was to compare dietary intake and status of polyunsaturated fatty acids (PUFA) in plasma and erythrocyte phospholipids metabolically healthy-and unhealthy, obese and non-obese persons. Metabolic health status in 171 participants was defined according to criteria for metabolic syndrome. Obese and non-obese metabolically unhealthy persons (MUHO and MUHNO) had higher energy intake of n-6 PUFA (7.82±1.03 and 7.49±0.86), and lower intake of n-3 PUFA (0.60±0.12 and 0.62±0.11) compared to obese and non-obese metabolically healthy persons (MHO and MHNO) (5.92±0.63 and 5.72±0.67; 1.20±0.07 and 1.22±0.09, respectively), and higher n-6/n-3 PUFA ratio. Plasma level of n-6 PUFA was lower in MUHO and MUHNO groups (38.49±3.71 and 38.53±2.19) compared to MHNO (40.90±2.43), while n-3 PUFA status was lower in obese than in non-obese persons (3.58±0.79 and 3.50±1.02 vs 4.21± 0.80 and 4.06±1.15). MHO group had higher eicosapentaenoic/arachidonic acid ratio and estimated desaturase (SCD16, D6D) and elongase activity in plasma phospholipids compared to MHNO. Low intake of n-3 PUFA is directly associated with metabolic risk factors. These results indicated that obesity is closely associated with low levels of n-3 PUFA in plasma phospholipids, suggesting that dietary modifications including n-3 PUFA supplementation appear to be suitable therapeutic strategy in obese persons.