Egg-Phosphatidylcholine Attenuates T-Cell Dysfunction in High-Fat Diet Fed Male Wistar Rats

Abstract

Obesity is associated with immune dysfunction including an impaired T-cell function characterized by a lower IL-2 (proliferation marker) production after stimulation. Phosphatidylcholine (PC), a form of choline mostly found in eggs, has been shown to beneficially modulate T-cell responses during the lactation period by increasing the production of IL-2. To determine the impact of egg-PC as part of a high-fat diet on immune function we randomly fed male Wistar rats one of three diets containing the same amount of total choline but differing in the form of choline: 1—Control low fat [CLF, 10% wt/wt fat, 100% free choline (FC)]; 2— Control high-fat (CHF, 25% wt/wt fat, 100% FC); 3— PC high-fat (PCHF, 25% wt/wt, 100% PC). After 9 weeks of feeding, rats were euthanized. Cell phenotypes and ex vivo cytokine production by splenocytes stimulated with phorbol 12-myristate 13-acetate plus ionomycin (PMA+I), lipopolysaccharide (LPS) and pokeweed (PWM) were measured by flow cytometry and ELISA, respectively. Rats fed the PCHF diet had a lower proportion of CD3+ cells when compared to both the CLF and the CHF. Following PMA+I stimulation, splenocytes from the CHF group produced less IL-2 and TNF-α compared to CLF and PCHF groups. No significant differences in cytokine production were found among groups after LPS and PWM stimulation. Our results show that feeding a high-fat diet impairs T-cell responses, as measured by ex vivo cytokine production, which can be attenuated by providing egg-PC.

Effect of High-Fat and Low-Fat Dairy Products on Cardiometabolic Risk Factors and Immune Function in a Low Birthweight Swine Model of Diet-Induced Insulin Resistance

“…Previous findings in humans and rodents have demonstrated an impaired immune response to mitogen stimulation in the context of obesity and T2D (7,43,44). Here, we found that consuming a high-fat diet in the context of a LBW swine model of insulin resistance also led to impaired immune function, particularly impaired T cell function.…”

Phytochemical Analysis and Profiling of Antitumor Compounds of Leaves and Stems of Calystegia silvatica (Kit.) Griseb.

“…Gallic acid is an identified phenolic acid that has been reported to have an antitumor effect [ 55 ]. Additionally, chlorogenic acid is a phenylacrylate polyphenol compound that has been reported to have antitumor properties [ 56 ]. The identified polyphenols with antitumor properties in C. silvatica extract are catechin [ 57 ] and caffeic acid [ 58 ].…”

Consumption of Different Egg-Based Diets Alters Clinical Metabolic and Hematological Parameters in Young, Healthy Men and Women

“…Studies have shown that various clinical leukocyte parameters, including total white blood cells counts, absolute neutrophils and monocytes, and the ratio of neutrophils:lymphocytes and lymphocytes:monocytes are indicators of systemic inflammation and are positively associated with chronic metabolic diseases, such as metabolic syndrome and CVD [102][103][104]. In preclinical studies, whole egg and its lipid constituents have been shown to improve humoral immune status and restore T cell responsiveness, highlighting a potential modulatory role of egg intake in pathogen defense and clearance [32,33]. In clini-cal trials, egg intake has additionally been shown to reduce anti-inflammatory T regulatory and pro-inflammatory Th17 T cell counts, alter cytokine secretion from LPS-stimulated peripheral blood mononuclear cells, and improve clearance of active pulmonary tuberculosis from sputum cultures as part of a cholesterol-rich diet [30,31,99].…”

“…Similarly, while epidemiological studies have reported conflicting associations between egg intake and type 2 diabetes mellitus (T2DM) risk [15,22], intervention studies often report a null or beneficial effect of egg intake on traditional markers of insulin resistance [10,19,23] and do not incorporate emerging biomarkers, such as plasma concentrations of branched-chain amino acids and glycine [24,25]. Further, studies report minimal to no effects of egg intake on improving anthropometric and erythrocyte profiles [16,26,27] and fail to incorporate an assessment of clinical immune profiles-despite the utility of white blood cell (WBC) and differential leukocyte counts in predicting chronic disease risk [28,29] and evidence from animal and human studies suggesting that egg intake alters immune cell gene expression, responsiveness to lipopolysaccharide, and pathogen defenses [30][31][32][33].…”