Imbalance of the oxidant - antioxidant status by aspartame in the organs of immune system of Wistar albino rats

Abstract

Aspartame (L-aspartyl-L-phenylalanine methyl ester) is one of the most widely artificial sweeteners consumed in so many products worldwide in various countries which added to a large variety of food, most commonly found in low calorie beverages. On metabolism in humans and experimental animals, aspartame is rapidly and completely metabolized to aspartic acid (40%), phenylalanine (50%) and methanol (10%). Methanol, a toxic metabolite is primarily metabolized by oxidation to formaldehyde and then to formate; these processes are accompanied by the formation of superoxide anion and hydrogen peroxide. This study focus is to understand whether the oral administration of aspartame (40 mg/kg b.w) for 15, 30 and 90 days have any effect on the antioxidant status (enzymatic and non-enzymatic) in immune organs such as the spleen, thymus, lymph nodes and bone marrow of rats. To mimic human methanol metabolism, folate deficient rats were used. After 15 days of aspartame administration, animals showed a significant increase in free radical production as indicated by the increase in both enzymatic (superoxide dismutase, catalase, glutathione peroxidase) and non-enzymatic (reduced glutathione and vitamin C) antioxidant level along with the marked increase in lipid peroxidation and nitric oxide level. However, after repeated long term administration (30 and 90 days), the generation of reactive free radicals overwhelmed the antioxidant defense as indicated by an increase in lipid peroxidation with the decrease in antioxidants level. This study concludes that administration of aspartame even at the Food and Drug Administration permitted level its repeated exposure causes oxidative stress by altering the oxidant/antioxidant balance in immune organs of the rats and its effects also reflected in the histology of the spleen and lymph nodes

Longer period of oral administration of aspartame on cytokine response in Wistar albino rats

“…Oral aspartame (75 mg/kg body weight/day) consumption causes oxidative stress in brain 21 and its (40 mg/kg bw/day) consumption caused oxidative stress in brain, 22 liver and kidney, 23 and also in immune organs. 24 This inadequacy, combined with the general limited knowledge about the safety/potential toxigenic effects of substances widely present in the industrialized diet, motivated the design of the current study. However, little is known about the effects of aspartame on cytokine expression.…”

Effects of aspartame on the evaluation of electrophysiological responses in Wistar albino rats

“…Reactive oxygen species (ROS) play a role in elevating central and peripheral sympathetic activity by increasing nitric oxide production [31]. Our previous study showed that aspartame acts as a chemical stressor, alters the oxidative-antioxidative balance [10,11], increases oxidative stress, and depresses HRV [32]. When a person is exposed to a stressor, the autonomic nervous (ANS) system is triggered: the parasympathetic nervous system is suppressed, and the sympathetic nervous system is activated [24].…”

“…Recently, based on previous studies, the ability of aspartame and its metabolites to alter the oxidative status of the cells via reactive oxygen species (ROS) generation and the modulation of intracellular antioxidant enzyme levels were investigated. Oral aspartame consumption at 75 mg/(kg bw/day) has been found to cause oxidative stress in the brain and liver [6,7], and oral aspartame consumption at 40 mg/(kg bw/day) has been found to cause oxidative stress in the brain [8], liver and kidney [9], and immune organs [10] and to alter immune response [11]. The inadequacy of past studies, combined with the general limited knowledge about the safety/potential toxigenic effects of substances widely present in the industrialized diet, motivated the design of this experiment.…”

Aspartame—True or False? Narrative Review of Safety Analysis of General Use in Products

“…Aspartame also stimulates the sympathetic nervous system by causing an increase in cortisol steroid levels in the adrenal glands via the hypothalamic-pituitary-adrenal (HPA) axis (Table 2) [93,94]. It also changes the composition of the gut microbiota [95,96].…”