Effects of Redox Disturbances on Intestinal Contractile Reactivity in Rats Fed with a Hypercaloric Diet

Abstract

Few studies have associated the effects of changes in caloric intake and redox disturbances in the gastrointestinal tract. Therefore, the present study aimed at evaluating the hypercaloric diet consumption influence on the contractile reactivity of intestinal smooth muscle, morphology, and oxidative stress of rat ileum. Wistar rats were randomly divided into groups that received a standard diet and fed with a hypercaloric diet for 8 weeks. Animals were euthanized, and the ileum was isolated to isotonic contraction monitoring. Morphology was evaluated by histological staining and oxidative stress by quantification of malondialdehyde levels and total antioxidant activity. Cumulative concentration-response curves to KCl and carbachol were attenuated in rats fed with a hypercaloric diet compared to those that received a standard diet. In addition, an increase in caloric intake promotes a rise in the thickness of the longitudinal smooth muscle layer of rat ileum and tissue malondialdehyde levels, characterizing lipid peroxidation, as well as a decrease in the antioxidant activity. Thus, it was concluded that the consumption of a hypercaloric diet impairs rat intestinal contractility due to mechanisms involving modifications in the intestinal smooth muscle architecture triggered by redox disturbances.

Potential Therapeutic Role of Dietary Supplementation with Spirulina platensis on the Erectile Function of Obese Rats Fed a Hypercaloric Diet

“…It has recently been shown that food supplementation with S. platensis promotes beneficial effects on the NO signaling pathway in the aorta of healthy rats [ 8 ], reduces oxidative stress and body adiposity in obese rats ileo [ 40 ], and prevents damage caused by a hypercaloric diet in erectile function [ 41 , 42 ], highlighting the promising role of seaweed in the prevention of various organic and metabolic disorders.…”

Spirulina platensis Consumption Prevents Obesity and Improves the Deleterious Effects on Intestinal Reactivity in Rats Fed a Hypercaloric Diet

“…In addition, supplementation with S. platensis completely prevented the decrease in both the potency and the relaxing effectiveness of the electromechanical component, bringing them back to what was observed in the control group, confirmed by the overlapping curves. Likewise, the hypercaloric diet reduced the contractile effectiveness of KCl, proving that it reduces the contractions caused by electromechanical coupling [ 33 ]. In contrast, Ferreira [ 27 ] did not observe any difference between animals fed a standard diet supplemented with S. platensis in relation to the obese group, and it is not possible to observe a reversal of such effects.…”

“…Recently, Souza et al [33] found that Wistar rats fed for 8 weeks on a hypercaloric diet showed reduced intestinal contractile efficacy compared to KCl and CCh. Thus, once the onset of obesity was confirmed and a reduction in ileal contractile reactivity was verified, the hypothesis was raised that 9 Oxidative Medicine and Cellular Longevity the consumption of the hypercaloric diet could decrease the contractile response to CCh by negatively modulating the muscarinic receptors present in the intestinal smooth muscle and that by its antioxidant role, supplementation could prevent this modulation by possibly acting on calcium influx.…”

“…The physiological solution of Tyrode was used and has the composition as follows (in mM): NaCl (150.0), KCl (2.7), CaCl 2 (1.8), MgCl 2 (2.0), NaHCO 3 (12.0), NaH 2 PO 4 (0.4), and D-glucose (5.5). The pH was adjusted to 7.4, and the ileum was stabilized for 1 h under a resting tension of 1 g at 37°C and bubbled with a carbogen mixture [ 33 , 34 ].…”

“…The standard diet (Presence®) contains 23% protein, 63% carbohydrate, and 4% lipids with 3.8 kcal energy density/g; the hypercaloric diet consisted of standard diet (Presence®), milk chocolate, peanuts, and sweet biscuits at a ratio of 3 : 2 : 2 : 1 [31]. The hypercaloric diet contains 23% protein, 45% carbohydrate, and 16% lipids with energy density 4.17 kcal/100 g by weight; this diet was prepared weekly and fed to the animals as granules [32,33] (Table 1). To 2Oxidative Medicine and Cellular Longevity prepare the hypercaloric diet, the feed, peanuts, and biscuits were ground and mixed, and the chocolate melted in a water bath and added to the mixture to form a homogeneous material that was molded and then dried in an oven (70°C) for 24 h and stored at room temperature (Table 1).…”