Antioxidantes enterais em lesões de isquemia e reperfusão em ratos

Abstract

Enteral antioxidants in ischemia/reperfusion injuries in rats Enteral antioxidants in ischemia/reperfusion injuries in rats Enteral antioxidants in ischemia/reperfusion injuries in rats Enteral antioxidants in ischemia/reperfusion injuries in rats Enteral antioxidants in ischemia/reperfusion injuries in rats Antioxidantes enterais em lesões de isquemia e reperfusão em ratos Antioxidantes enterais em lesões de isquemia e reperfusão em ratos Antioxidantes enterais em lesões de isquemia e reperfusão em ratos Antioxidantes enterais em lesões de isquemia e reperfusão em ratos Antioxidantes enterais em lesões de isquemia e reperfusão em ratos HUGO Methods Methods Methods Methods: Ninety adult male Wistar rats were used. An intestinal segment was isolated based on its vascular pedicle. A control biopsy was performed and the pedicle was sectioned and sutured again, ensuring a time of 60 minutes of ischemia followed by reperfusion. Sequential biopsies were performed at the end of the ischemic period and every 15 minutes during reperfusion. The treatment consisted of saline, vitamin C, vitamin E or a combination of the latter two. Quantitative and qualitative assessments of the biopsies were performed. Results Results ResultsResults Results: The groups treated with vitamin E alone or vitamin E combined with vitamin C showed a statistically significant attenuation of ischemia-reperfusion, with reduced loss of height of the villi and lower neutrophilic infiltration at the end of the study when compared to the control and vitamin C- INTRODUCTION INTRODUCTION INTRODUCTION INTRODUCTION INTRODUCTIONT he restoration of blood flow to an ischemic tissue can lead to greater harm than that originally caused by ischemia. This event is called ischemia and reperfusion (I/R) injury. The small intestine is particularly susceptible to injury from I/R 1 and its occurrence is associated with high morbidity and mortality 2 . Although the mechanisms involved are not fully elucidated, it is believed that oxidative stress mediators, such as reactive oxygen species (ROS), polymorphonuclear neutrophils (PMN) and nitric oxide (NO) play an important role 3 . Due to the involvement of ROS in I/R injury, various antioxidants have been tested, among them vitamin C (ascorbic acid) and vitamin E. Ascorbic acid is an water-soluble antioxidant with chelating and reducing properties and it is used to prevent I/R injury 4 . Vitamin E (á-tocopherol) is a nonenzymatic, lipid soluble antioxidant that acts against oxidative stress by stabilizing membrane unsaturated fatty acids. Thus, tissues treated with vitamin E have an increased capacity to reduce ROS and be protected against membrane lipid peroxidation 5 . Vitamins C and E can act synergistically because ascorbic acid is unable to reduce the peroxyl radical, but it can regenerate á-tocopherol from the tocoferoxil radical, recycling the á-tocopherol 6 . I/R can occur in a variety of clinical situations, one being the microsurgical transfer of jejunal segments. The jejunal flap was first described in 1957...

Honey: A Novel Antioxidant

“…The beneficial effects of different antioxidants, especially vitamins C and E, are well documented in various disease models in both rodents and humans [ 138 , 139 , 140 , 141 , 142 ]. However, some demerits have also been reported for some of these antioxidants or vitamins [ 143 ].…”

“…Many of these constituents may produce synergistic antioxidant effects. Besides, unlike vitamin C or E which requires the other for regeneration into the active form [ 138 , 139 ], this may be unnecessary with the use of honey. If any of the antioxidant constituents in honey exhibits pro-oxidant properties, there would be sufficient antioxidants for its regeneration.…”

Oral post-treatment supplementation with a combination of glutamine, citrulline, and antioxidant vitamins additively mitigates jejunal damage, oxidative stress, and inflammation in rats with intestinal ischemia and reperfusion

“…In mice with myocardial ischemia and reperfusion, pretreatment of α-tocopherol, i.e., a fat-soluble vitamin with potent antioxidant activity, significantly decreased cardiac ROS production, neutrophil infiltration, and MPO activity [32]. Pretreatment with vitamins C and E markedly reduced lipid peroxidation products, increased antioxidant enzyme activity, and mitigated jejunal damage in animals with ischemia and reperfusion injury [9,33,34]. In this study, IIR rats administered oral posttreatment supplementation of vitamin C plus E showed significantly reduced plasma IL-6 and NOx (Table 4), jejunal TBARS levels (Table 3), and MPO activity (Fig 4C).…”

“…Evidence indicates that oxidative stress plays a key role in the pathogenesis of IIR injury [3]. For example, pretreatment with antioxidant vitamins, such as vitamins C and E, showed protective effects against IIR-induced intestinal morphological lesions and neutrophil infiltration, increased the end products of lipid peroxidation, and decreased glutathione and antioxidant enzyme activity, including superoxide dismutase, glutathione peroxidase, and catalase [9][10][11][12].…”