N‐3 Polyunsaturated Fatty Acids Modulate In‐Vitro T Cell Function in Type I Diabetic Patients

Abstract

In this work, we assessed the in-vitro effects of eicosapentaenoic acid (EPA; C20:5n-3) and docosahexaenoic acid (DHA; C22:6n-3) (final concentration, 15 microM) on T cell blastogenesis, interleukin-2 and -4 (IL-2, IL-4) secretion, fatty acid composition and intracellular oxidative status in type I diabetic patients with or without complications. Con A stimulated lymphocyte proliferation, glucose uptake, intracellular reduced glutathione levels and catalase activity were lower in diabetics as compared to controls, regardless to the presence of complications. EPA and DHA diminished T-lymphocyte proliferation and IL-2 production but enhanced IL-4 secretion in both diabetic and control groups. No changes in the levels of reduced glutathione and in the activities of catalase and SOD were observed in control T cells cultured in the presence of EPA and DHA. However, in diabetic patients, addition of n-3 PUFA to culture induced an increase in T cell levels of reduced glutathione and hydroperoxide, and in activities of catalase and SOD. Low levels of arachidonic acid (C20:4n-6) were found in plasma membrane phospholipids of lymphocytes from diabetic patients compared to controls. Incubation of lymphocytes with EPA and DHA was associated with an incorporation of these fatty acids in membrane phospholipids. In conclusion, the beneficial effects of n-3 PUFA on T cell functions in type I diabetes could be attributed to their suppressive action and modulation of cytokine secretion, and to the improvement of intracellular oxidative status.

Type 2 Diabetes, PUFAs, and Vitamin D: Their Relation to Inflammation

“…This interaction requires high concentrations of AA, and any change in this may affect TCR-MHC complex affinity and TCR signal transduction, determining the nature and magnitude of the T-cell response. There are in vitro studies showing the regulatory effect of AA metabolites on the development and function of immune system cells including growth and differentiation of thymocytes, proliferation and migration of T-cells, Th1 and Th2 response mediated by cytokines, antigen presentation, macrophage regulation, TNF α , IL-1 and IL-2 production, as well as suppressor T-cell induction [3, 53, 55–57]. …”

In vitro effects of oil's fatty acids on T cell function in gestational diabetic pregnant women and their newborns 油类脂肪酸在体外对妊娠期糖尿病孕妇及其新生儿的T细胞功能的影响

“…Oxidative stress was found to influence the proliferation, activation, cytokine secretion and T‐cell homeostasis . Enhanced intracellular free radical production or reduced antioxidant enzyme activity have been shown to induce T lymphocyte oxidative stress …”

“…Modulation of immune system by consumption of vegetable oils protected against some diseases. N‐3 polyunsaturated fatty acids (PUFA) improved T cell intracellular oxidative status in diabetes . An important source of dietary n‐3 PUFA is α ‐linolenic acid (ALA, C18:3 n‐3), supplied by vegetable sources such as linseed oil.…”

“…Specific cellular immunity can be assayed in vitro by mitogen‐induced lymphocyte proliferation. We have previously used this methodology to test several chemical substances and the results were quite promising . The addition of fatty acids in culture medium of immune cells affects various parameters of the immune response .…”

Elevation of oxidative stress markers in Type 1 diabetic children

“…ORAC has been found to be a good index of oxidative stress in diabetes mellitus (Merzouk et al, 2004). Our data revealed that the total antioxidant activity (ORAC) decreased in the plasma of children with diabetes in favor of an oxidative stress in such patients.…”