Oral Administration of Sodium Nitrate to Metabolic Syndrome Patients Attenuates Mild Inflammatory and Oxidative Responses to Acute Exercise

Abstract

<jats:p>The beneficial effects of exercise for the treatment and prevention of metabolic syndrome pathologies have been related to its anti-inflammatory and antioxidant effects. Dietary nitrate supplementation is an emerging treatment strategy to alleviate the symptoms of metabolic syndrome affections and to improve vascular function. In this double-blind crossover trial, metabolic syndrome patients performed two exercise tests for 30 min at 60–70% maximal heart rate after the intake of a placebo or a nitrate-enriched beverage. Acute exercise increased the plasma concentration of TNFα, intercellular adhesion molecule ICAM1, PGE1, PGE2 and the newly detected 16-hydroxypalmitic acid (16-HPAL) in metabolic syndrome patients. The cytokine and oxylipin production by peripheral blood mononuclear cells (PBMCs) and neutrophils could be responsible for the plasma concentrations of TNFα and IL6, but not for the plasma concentration of oxylipins nor its post-exercise increase. The intake of sodium nitrate 30 min before exercise increased the concentration of nitrate and nitrite in the oral cavity and plasma and reduced the oxygen cost of exercise. Additionally, nitrate intake prevented the enhancing effects of acute exercise on the plasma concentration of TNFα, ICAM1, PGE1, PGE2 and 16-HPAL, while reducing the capabilities of PBMCs and neutrophils to produce oxylipins.</jats:p>

Dietary Sodium Nitrate Activates Antioxidant and Mitochondrial Dynamics Genes after Moderate Intensity Acute Exercise in Metabolic Syndrome Patients

“…These contrasting results reinforce the fact that the age and physical and training status or pathologic situation of the subjects markedly affect the metabolic and molecular response to a given exercise challenge and point to the idea that acute exercise may worsen the oxidative and mitochondrial status of PBMCs in metabolic syndrome patients. This response is in accordance with previous results of the effects of acute exercise performed by metabolic syndrome patients on plasma oxidative and pro-inflammatory markers [6]. Acute exercise increases the plasma concentration of TNFα, intercellular adhesion molecule (ICAM1), and products of saturated and polyunsaturated fatty acid peroxidation, such as PGE1, PGE2 and 16-hydroxypalmitate.…”

“…These potentially harmful effects of acute exercise on the oxidative and inflammatory status of metabolic syndrome subjects were prevented by the intake of a nitrate-rich beverage before exercise. In this instance, it was reported that nitrate intake prevents the enhancing effects of acute exercise on the plasma concentration of TNFα, ICAM1, PGE1, PGE2 and 16-HPAL, while it reduces the capabilities of PBMCs and neutrophils to produce oxylipins [6].…”

“…Nitrate intake before exercise reduces the oxygen cost of exercise both in sportsmen and in metabolic syndrome subjects [6,[48][49][50]. In the present study, we confirm the reduction of oxygen cost of exercise performed by metabolic syndrome patients who consumed the nitrate-rich beverage, without influencing the energy source (lipids or carbohydrates) used to sustain the exercise, and the operative nitrate-nitrite-nitric oxide pathway through the reduction of nitrate to nitrite in the oral cavity and the increased plasma levels of nitrate and nitrite after acute exercise.…”

“…Dietary nitrate may have therapeutic utility against obesity and associated metabolic complications, possibly by increasing adipocyte mitochondrial respiration and by dampening inflammation and oxidative stress [3]. In fact, animal, human and epidemiological studies have shown that dietary nitrate and nitrite modulate inflammatory processes and immune cell function and phenotypes [4][5][6][7]. The current evidence on the efficacy of nitrate-rich plant foods and of other sources of nitrate and nitrite suggests that J. Clin.…”

“…Although acute exercise may act as an inducer of antioxidant and anti-inflammatory status in healthy young sportsmen [12], it has the opposite effect on metabolic syndrome patients. Acute exercise of moderate intensity and duration increases the plasma levels of the pro-inflammatory cytokines tumor necrosis factor α (TNFα) and intercellular adhesion molecule 1 (ICAM1), of prostaglandin E1 (PGE1) and prostaglandin E2 (PGE2) and of 16 hydroxyl-palmitate (16HPAL) in metabolic syndrome patients [6], pointing to a mild pro-inflammatory response of metabolic syndrome patients to acute exercise. This pro-inflammatory response, which can be related to an increased production of reactive oxygen species during the exercise session, is attenuated by the intake of sodium nitrate 30 min before exercise [6], which avoids the enhancing effects of acute exercise on pro-inflammatory cytokine production and on prostaglandins and other oxylipins plasma levels, while reducing the capabilities of PBMCs and neutrophils to produce these oxylipins.…”