RETRACTED: Glutamine Metabolism and Its Role in Immunity, a Comprehensive Review

Abstract

In the body of an animal, glutamine is a plentiful and very useful amino acid. Glutamine consumption in the body of animals in normal or disease conditions is the same or higher than the glucose. Many in vivo as well as in vitro experiments have been conducted to evaluate the importance of glutamine. Glutamine is a valuable nutrient for the proliferation of the lymphocytes. It also plays a crucial role in the production of cytokines, macrophages, phagocytic, and neutrophil to kill the bacteria. Most of the metabolic organs like the liver, gut, and skeletal muscles control the circulation and availability secretion of glutamine. In catabolic and hypercatabolic conditions, glutamine can turn out to be essential and plays a vital role in metabolism; however, availability may be compromised due to the impairment of homeostasis in the inter-tissue metabolism of amino acids. This is why the supplementation of glutamine is commonly used in clinical nutrition and is especially recommended to immune-suppressed persons. Despite this, in catabolic and hyper-catabolic conditions, it is challenging due to the amino acid concentration in plasma/bloodstream and glutamine should be provided via either the oral, enteral or parenteral route. However, the effect of glutamine as an immune-based supplement has been previously recognized as many research studies conducted in vivo and in-vitro evaluated the beneficial effects of glutamine. Hence, the present study delivers a combined review of glutamine metabolism in essential organs of the cell immune system. In this review, we have also reviewed the metabolism and action of glutamine and crucial problems due to glutamine supplementation in catabolic conditions.

Shared and unique metabolic features of the malignant and benign thyroid lesions determined with use of 1H HR MAS NMR spectroscopy

“…The concentration of this metabolite in the thyroiditis was similar as in the lesions. The immune cells utilize glutamine at high rates under the metabolic stress conditions 47 . Thus, the increased glutamate level in the thyroiditis as compared to goiter may be related to the enhanced conversion of glutamate from glutamine.…”

The Role of Oat Nutrients in the Immune System: A Narrative Review

“…Additionally, activated B and T cells have an increased demand for glutamine for the production of IFN-γ and IL-2 and T cell proliferation [ 99 , 124 ]. Recent data showed that glutamine supplementation and metabolism is a vital part of the immune function and greatly reduces the risk of infectious complications in critically ill or surgical patients [ 125 , 126 ]. Oats, including all oat products listed in Table 1 , contain proteins at 12–13% dry weight, equivalents to at least 5.0 g protein per 40-g serving and provision of 8.9% of daily protein requirement of 0.8 g/kg body weight for a 70-kg American male adult ( Table 1 and Table 2 ).…”

Immuno-Metabolism: The Role of Cancer Niche in Immune Checkpoint Inhibitor Resistance

“…Glutamine is another element necessary for cellular proliferation and differentiation [ 116 ], and can promote proliferation in cancer cells [ 117 , 118 ]. Glutaminase (GLS) and glutamine synthetase (GS) are the two major enzymes involved in glutamine metabolism.…”