L-Glutamine and Physical Exercise Prevent Intestinal Inflammation and Oxidative Stress Without Improving Gastric Dysmotility in Rats with Ulcerative Colitis

Therapeutic Benefits of Tuna Oil by In Vitro and In Vivo Studies Using a Rat Model of Acetic Acid-Induced Ulcerative Colitis

Ulcerative colitis (UC), an inflammation of the colon lining, represents the main form of inflammatory bowel disease IBD. Nutritional therapy is extremely important in the management of ulcerative colitis. Fish oil contains long-chain omega-3 polyunsaturated fatty acids, which have beneficial effects on health, including anti-inflammatory effects. This study aims to investigate the benefits of bluefin tuna oil extracted by the Soxhlet method in vitro by determining the anti-radical and anti-inflammatory activities and in vivo by evaluating the preventive and curative effects. The experiments were carried out using two doses of oil (100 and 260 mg/kg) and glutamine (400 and 1000 mg/kg) on the acetic acid-induced UC model. UC has been induced in Wistar rats by intrarectal administration of a single dose of 1 mL acetic acid (5% v/v in distilled water). The obtained results indicate that tuna oil and glutamine have a significant anti-free radical effect. Tuna oil has a marked anti-inflammatory power based on membrane stabilization and inhibiting protein denaturation. The reduction of various UC parameters, such as weight loss, disease activity score DAS, and colonic ulceration in rats pre-treated with tuna oil and glutamine, demonstrate that these treatments have a significant effect on UC. Total glutathione GSH, superoxide dismutase SOD, and catalase activities are significantly restored in the tuna oil and glutamine groups, while lipid peroxidation has been markedly reduced.

Identification of subclusters and prognostic genes based on GLS-associated molecular signature in ulcerative colitis

Ulcerative colitis (UC) is a chronic and recurrent inflammatory disease that affects the colon and rectum. The response to treatment varies among individuals with UC. Therefore, the aim of this study was to identify and explore potential biomarkers for different subtypes of UC and examine their association with immune cell infiltration. We obtained UC RNA sequencing data from the GEO database, which included the training set GSE92415 and the validation set GSE87473 and GSE72514. UC patients were classified based on GLS and its associated genes using consensus clustering analysis. We identified differentially expressed genes (DEGs) in different UC subtypes through a differential expression analysis of the training cohort. Machine learning algorithms, including Weighted Gene Co-Expression Network Analysis (WGCNA), Least Absolute Shrinkage and Selection Operator (LASSO), and Support Vector Machine Recursive Feature Elimination (SVM-RFE), were utilized to identify marker genes for UC. The CIBERSORT algorithm was used to determine the abundance of various immune cells in UC and their correlation with UC signature genes. Finally, we validated the expression of GLS through in vivo and ex vivo experiments. The expression of GLS was found to be elevated in patients with UC compared to normal patients. GLS and its related genes were able to classify UC patients into two subtypes, C1 and C2. The C1 subtype, as compared to the C2 subtype, showed a higher Mayo score and poorer treatment response. A total of 18 DEGs were identified in both subtypes, including 7 up-regulated and 11 down-regulated genes. Four UC signature genes (CWH43, HEPACAM2, IL24, and PCK1) were identified and their diagnostic value was validated in a separate cohort (AUC > 0.85). Furthermore, we found that UC signature biomarkers were linked to the immune cell infiltration. CWH43, HEPACAM2, IL24, and PCK1 may serve as potential biomarkers for diagnosing different subtypes of UC, which could contribute to the development of targeted molecular therapy and immunotherapy for UC.

Glutamine prevents high-fat diet-induced hepatic lipid accumulation in mice by modulating lipolysis and oxidative stress

Metabolic-associated fatty liver disease (MAFLD) is related to metabolic dysfunction and is characterized by excess fat storage in the liver. Several studies have indicated that glutamine could be closely associated with lipid metabolism disturbances because of its important role in intermediary metabolism. However, the effect of glutamine supplementation on MAFLD progression remains unclear. Here, we used a high-fat diet (HFD)-induced MAFLD C57BL/6 mouse model, and glutamine was supplied in the drinking water at different time points for MAFLD prevention and reversal studies. A MAFLD prevention study was performed by feeding mice an HFD concomitant with 4% glutamine treatment for 24 weeks, whereas the MAFLD reversal study was performed based on 4% glutamine treatment for 13 weeks after feeding mice an HFD for 10 weeks. In the prevention study, glutamine treatment ameliorated serum lipid storage, hepatic lipid injury, and oxidative stress in HFD-induced obese mice, although glutamine supplementation did not affect body weight, glucose homeostasis, energy expenditure, and mitochondrial function. In the MAFLD reversal study, there were no noticeable changes in the basic physiological phenotype and hepatic lipid metabolism. In summary, glutamine might prevent, but not reverse, HFD-induced MAFLD in mice, suggesting that a cautious attitude is required regarding its use for MAFLD treatment.

Phase angle values and ultra-processed food consumption are associated with changes in oxidative stress in inflammatory bowel disease patients

BACKGROUND & AIMS

Changes in dietary habits including increased intake of refined sugars and fats and decreased intake of fiber have been suggested as potential risk factors for the development of inflammatory bowel diseases (IBD). Bioelectrical impedance analysis-derived phase angle (PhA) has been gaining attention in the clinical evaluation of nutritional status. In this study, we for the first time investigated the relationship of PhA and ultra-processed food intake with oxidative stress, body composition and biochemical parameters in adult patients with IBD.

METHODS

Body composition and PhA were evaluated through electrical bioimpedance. Nitrite (Nox), myeloperoxidase (MPO), glutathione (GSH), malondialdehyde (MDA) and superoxide dismutase (SOD) levels were determined in both groups. Food consumption was obtained by a food frequency questionnaire (FFQ).

RESULTS

In comparison with the control group, the IBD group had increased (p < 0.05) concentrations of Nox (19.95 ± 1.4 vs. 35.43 ± 7.7 μM), MDA (0.70 ± 0.31 vs. 4.56 ± 0.62 nmol/L), and GSH (9.35 ± 0.38 vs. 10.74 ± 0.51 mg NPSH/μL plasma). PhA was positively correlated with GSH (R2:0.22; p:0.02) and SOD (R2:0.25; p:0.01). IBD patients ingested higher amounts of ultra-processed foods (IBD:17.04 ± 2.76 vs. Control:24.88 ± 2.30%). However, IBD patients had better consumption of unprocessed or minimally processed foods (IBD:79.06 ± 3.07 vs. Control:67.83 ± 2.32%). We found a positive correlation between ultra-processed food consumption and MDA (R2 0.43; p:0.01).

CONCLUSIONS

PhA may be a practical and effective measure in clinical follow-up of IBD patients, being associated with bilirubin levels and antioxidant enzymes. Also, we recommend evaluating consumption of ultra-processed foods, since this was related with increasing oxidative stress markers in clinical follow-up of IBD patients.

Alanyl-Glutamine Dipeptide Attenuates Non-Alcoholic Fatty Liver Disease Induced by a High-Fat Diet in Mice by Improving Gut Microbiota Dysbiosis

Non-alcoholic fatty liver disease (NAFLD) manifests as a persistent liver ailment marked by the excessive buildup of lipids within the hepatic organ accompanied by inflammatory responses and oxidative stress. Alanyl-glutamine (AG), a dipeptide comprising alanine and glutamine, is commonly employed as a nutritional supplement in clinical settings. This research aims to evaluate the impact of AG on NAFLD triggered by a high-fat diet (HFD), while concurrently delving into the potential mechanisms underlying its effects. The results presented herein demonstrate a notable reduction in the elevated body weight, liver mass, and liver index induced by a HFD upon AG administration. These alterations coincide with the amelioration of liver injury and the attenuation of hepatic histological advancement. Furthermore, AG treatment manifests a discernible diminution in oil-red-O-stained regions and triglyceride (TG) levels within the liver. Noteworthy alterations encompass lowered plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDLC) concentrations, coupled with elevated high-density lipoprotein cholesterol (HDLC) concentrations. The mitigation of hepatic lipid accumulation resultant from AG administration is aligned with the downregulation of ACC1, SCD1, PPAR-γ, and CD36 expression, in conjunction with the upregulation of FXR and SHP expression. Concomitantly, AG administration leads to a reduction in the accumulation of F4/80-positive macrophages within the liver, likely attributable to the downregulated expression of MCP-1. Furthermore, AG treatment yields a decline in hepatic MDA levels and a concurrent increase in the activities of SOD and GPX. A pivotal observation underscores the effect of AG in rectifying the imbalance of gut microbiota in HFD-fed mice. Consequently, this study sheds light on the protective attributes of AG against HFD-induced NAFLD through the modulation of gut microbiota composition.

Physical exercise alleviates oxidative stress in brown adipose tissue and causes changes in body composition and nutritional behavior in rats with polycystic ovary syndrome

AIM

Polycystic Ovary Syndrome (PCOS) is a very common endocrine disorder in women. We investigate the effect of physical exercise on body composition, nutritional parameters, and oxidative stress in rats with PCOS.

METHODS

Female rats were into three groups: Control, PCOS, and PCOS + Exercise. PCOS was induced by letrozole (1 mg/kg via p.o.) for 21 days consecutively. Physical exercise was swimming, for 21 consecutive days, 1 h/day with 5 % load. In all groups, we assessed the nutritional and murinometric parameters, body composition, thermography, and oxidative stress in brown adipose tissue (BAT) and peri-ovarian adipose tissue (POAT).

KEY FINDINGS

In PCOS we observed an increase (P < 0.05) in body weight vs. the Control group. But, the PCOS + Exercise group prevent this weight gain (P < 0.05). The temperature in BAT, decrease (P < 0.05) in the PCOS group vs. Control group. PCOS + Exercise prevented this reduction (P < 0.05) in BAT temperature vs. PCOS groups. We observed decreases (P < 0.05) in Lee Index and BMI in POS + Exercise vs. PCOS group. In PCOS rats, we observed an increase (P < 0.05) in murinometric (SRWG, EI, and FE) and body composition parameters (TWB, ECF, ICF, and FFM) vs. the Control group. The PCOS + Exercise prevents (P < 0.05) these changes in all groups, compared with PCOS. Regarding the BAT, we observe an increase (P < 0.05) in MPO and MDA levels in the PCOS vs. Control group. PCOS + Exercise prevents (P < 0.05) these increases vs. the PCOS group.

SIGNIFICANCE

PCOS modifies body composition, and nutritional parameters, and induces changes in oxidative stress in BAT. Physical exercise prevented these alterations.

Nox4-and Tf/TfR-mediated peroxidation and iron overload exacerbate neuronal ferroptosis after intracerebral hemorrhage: Involvement of EAAT3 dysfunction

Intracerebral hemorrhage (ICH) induces high mortality and disability. Neuronal death is the principal factor to unfavourable prognosis in ICH. However, the mechanisms underlying this association remain unclear. In this study, we investigated the molecular mechanisms by which neuronal ferroptosis occurs after ICH and whether the use of corresponding modulators can inhibit neuronal death and improve early outcomes in a rat ICH model. Our findings indicated that Nox4 and TF/TfR were upregulated in the perihematomal tissues of ICH rats. Oxidative stress and iron overload induced by Nox4 and TF/TfR promoted neuronal ferroptosis post-ICH. In contrast, application of Nox4-siRNA and the deferoxamine (DFO) attenuated peroxidation and iron deposition in the hemorrhagic brain, alleviated neuronal ferroptosis, and improved sensorimotor function in ICH rats. Additionally, our findings indicated that the post-ICH neuronal reduced glutathione (GSH) depletion were not related to dysfunctional glutamine delivery in astrocytes but rather to downregulation of EAAT3 due to lipid peroxidation-induced dysfunction in the neuronal membrane. These findings indicate that ferroptosis is involved in neuronal death in model rats with collagenase-induced ICH. Oxidative stress and iron overload induced by Nox4 and TF/TfR exacerbate ferroptosis after ICH, while Nox4 downregulation and iron chelation exert neuroprotective effects. The present results highlight the cysteine importer EAAT3 as a potential biomarker of ferroptosis and provide insight into the neuronal death process that occurs following ICH, which may aid in the development of translational treatment strategies for ICH.

P2X7 receptor antagonist improves gastrointestinal disorders in spontaneously hypertensive rats

The purinergic system participates in the control of blood pressure. Hypertension promotes the occurrence of gastrointestinal disorders such as intestinal inflammation and gastric emptying delay. This study aimed i) to investigate the participation of the P2X7 receptor blocker Brilliant Blue G (BBG) on gastric emptying of solids and changes in oxidative stress in the gastric fundus, duodenum, and colon of spontaneously hypertensive rats (SHR) and ii) to study the putative relationship of this effect with the renin-angiotensin system. Rats were divided into five groups: Control, SHR, SHR+BBG, SHR+BBG+ATP, and SHR+BBG+ANG II. In the gastrointestinal tract, we assessed gastric emptying (GE) and oxidative stress markers (NOx, MPO, GSH, SOD). We observed a decrease in the GE rate (P<0.05) in SHR vs control rats (21.8±2.0% vs 42.8±3.5%). The decrease in GE was returned (P<0.05) to control levels by BBG in SHR rats (21.8±2.0% vs 41.6±3.2%). Co-administration of ATP or ANG II together with BBG bypassed the effect of the P2X7 antagonist on GE in SHR (P<0.05) (21.9±5.0% vs 25.6±3.0% vs 41.6±3.2%). The MPO activity increased (P<0.05) in the gastric fundus of SHR compared to control rats (6.12±2.26 vs 0.077±0.02 UMPO/mg tissue); this effect was prevented (P<0.05) by BBG (0.55±0.15 vs 6.12±2.26 UMPO/mg tissue). Data demonstrated that blockage of P2X7 receptors with BBG can improve the GE delay and oxidative stress biomarkers in SHR animals. This preventive effect of BBG on GE delay was abrogated by ANG II and ATP, thus prompting crosstalk between renin-angiotensin and the purinergic signaling systems underlying this phenomenon.

Corynoline ameliorates dextran sulfate sodium-induced colitis in mice by modulating Nrf2/NF-κB pathway

OBJECTIVE

Corynoline is an active substance extracted from Corydalis bungeana Turcz and exerts a therapeutic effect in multiple diseases by alleviating inflammatory response. The present study sought to elucidate the role of corynoline in ulcerative colitis (UC).

METHODS

The experimental colitis models were induced in BALB/c mice via receiving a drinking water supplemented with 3.5% (I) dextran sulfate sodium (DSS) ad libitum for 7 days.

RESULTS

Corynoline administration inhibited body weight loss, colon shortening, disease activity index and colonic pathomorphological changes in DSS-treated mice. Besides, corynoline down-regulated the levels of pro-inflammatory interleukin (IL)-1β, IL-6 and tumor necrosis factor Alpha (TNF-α), as well as decreased myeloperoxidase (MPO) activity in the colon of DSS-treated mice. In addition, severe oxidative stress in the colonic tissues of DSS-treated was mitigated by corynoline treatment. However, these beneficial effects were reversed by a specific nuclear factor E2-related factor 2 (Nrf2) inhibitor ML385 intervention. Further evidence confirmed that corynoline promoted Nrf2 nuclear migration and heme oxygenase-1 gene expression in the colonic tissues of UC mice. Besides, corynoline treatment restrained colonic nuclear factor-kappa B (NF-κB) activation as proved by the decrease in phosphorylation and nuclear translocation of NF-κB.

CONCLUSIONS

Corynoline ameliorates DSS-induced mouse colitis, which may provide a promising therapeutic strategy for UC treatment.

Sinigrin Attenuates the Dextran Sulfate Sodium-induced Colitis in Mice by Modulating the MAPK Pathway

Ulcerative colitis (UC) is an intestinal inflammatory disease characterised by the loss of intestinal crypts, edema, mucosal ulceration, and infiltration of inflammatory cells in the mucosa. The current study aimed to investigate the protective and therapeutic effects of sinigrin and underlying mechanisms in a dextran sulfate sodium (DSS)-induced mouse model of ulcerative colitis. DSS-induced colitis models were used to demonstrate sinigrin's therapeutic/protective action. Mice were orally administered with sinigrin (15 mg/kg or 30 mg/kg) for a period of 12 days in both prophylactic and therapeutic models. Animal weights, stool consistency, and bleeding parameters were measured throughout the experimental period. After the experimental period, colon lengths were measured, and colon tissues were harvested to determine the levels of oxidative stress-inducing factors (nitrates and MDA levels) and anti-oxidant components (GSH, SOD, and catalase). Furthermore, gene expression analysis, IL-17 levels, and inflammatory marker expressions were measured using RT-qPCR, ELISA, and immunohistochemical methods respectively. Furthermore, histopathological observations and elucidation of the mechanism of action were determined using H&E analysis and Western blot analysis. Sinigrin treatment (in both prophylactic and therapeutic models) significantly mitigated the DSS-induced body weight loss, attenuated the colon length shrinkage, and improved the disease index score (p < 0.001). Further results revealed that sinigrin's protective/therapeutic effect is associated with a significant attenuation of pro‑inflammatory cytokine production (p < 0.001), reversing the anti-oxidant enzyme levels (p < 0.001) and substantial improvement (2 folds) of the disruption of the colonic morphology in colon tissues compared to DSS control. Immunohistochemical analysis showed that sinigrin treatment remarkably reduced the DSS-induced myeloperoxidase, neutrophil elastase, and CD68 expression in colon tissues. Additionally, sinigrin successfully abrogated the DSS-induced IL-17 levels (p < 0.001) and improved the colonic barrier in colon tissues. Overall, these results demonstrated that sinigrin exerts protective and therapeutic effects on DSS‑induced colitis, by enhancing the anti-oxidant enzymes and suppressing the intestinal inflammatory cascade of markers by regulating the MAPK pathway.

Insights into diet-associated oxidative pathomechanisms in inflammatory bowel disease and protective effects of functional amino acids

There has been a substantial rise in the incidence and prevalence of clinical patients presenting with inflammatory bowel disease (IBD), which includes Crohn's disease and ulcerative colitis. Accumulating evidence has corroborated the view that dietary factors (particularly diets with high levels of saturated fat or sugar) are involved in the development and progression of IBD, which is predominately associated with changes in the composition of the gut microbiota and an increase in the generation of reactive oxygen species. Notably, the ecological imbalance of the gut microbiome exacerbates oxidative stress and inflammatory responses, leading to perturbations of the intestinal redox balance and immunity, as well as mucosal integrity. Recent findings have revealed that functional amino acids, including L-glutamine, glycine, L-arginine, L-histidine, L-tryptophan, and hydroxyproline, are effectively implicated in the maintenance of intestinal redox and immune homeostasis. These amino acids and their metabolites have oxygen free-radical scavenging and inflammation-relieving properties, and they participate in modulation of the microbial community and the metabolites in the gut. The principal focus of this article is a review of recent advances in the oxidative pathomechanisms of IBD development and progression in relation to dietary factors, with a particular emphasis on the redox and signal transduction mechanisms of host cells in response to unbalanced diets and enterobacteria. In addition, an update on current understanding of the protective effects of functional amino acids against IBD, together with the underlying mechanisms for this protection, have been provided.

Alanyl-Glutamine Protects Mice against Methionine- and Choline-Deficient-Diet-Induced Steatohepatitis and Fibrosis by Modulating Oxidative Stress and Inflammation

Nonalcoholic steatohepatitis (NASH) is a common chronic liver disease with increasing prevalence rates over years and is associated with hepatic lipid accumulation, liver injury, oxidative stress, hepatic inflammation, and liver fibrosis and lack of approved pharmacological therapy. Alanyl-glutamine (Ala-Gln) is a recognized gut-trophic nutrient that has multiple pharmacological effects in the prevention of inflammation- and oxidative-stress-associated diseases. Nevertheless, whether Ala-Gln has a protective effect on NASH still lacks evidence. The aim of this study is to explore the influence of Ala-Gln on NASH and its underlying mechanisms. Here, C57BL/6 mice were fed a methionine- and choline-deficient (MCD) diet to establish the model of NASH, and Ala-Gln at doses of 500 and 1500 mg/kg were intraperitoneally administered to mice along with a MCD diet. The results showed that Ala-Gln treatment significantly attenuated MCD-induced hepatic pathological changes, lowered NAFLD activity score, and reduced plasma alanine transaminase (ALT), aspartate transaminase (AST) and lactate dehydrogenase (LDH) levels. Ala-Gln dramatically alleviated lipid accumulation in liver through modulating the expression levels of fatty acid translocase (FAT/CD36) and farnesoid X receptor (FXR). In addition, Ala-Gln exerted an anti-oxidant effect by elevating the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPX). Moreover, Ala-Gln exhibited an anti-inflammatory effect via decreasing the accumulation of activated macrophages and suppressing the production of proinflammatory mediators. Notably, Ala-Gln suppressed the development of liver fibrosis in MCD-diet-fed mice, which may be due to the inhibition of hepatic stellate cells activation. In conclusion, these findings revealed that Ala-Gln prevents the progression of NASH through the modulation of oxidative stress and inflammation and provided the proof that Ala-Gln might be an effective pharmacological agent to treat NASH.

Alanyl-Glutamine Protects against Lipopolysaccharide-Induced Liver Injury in Mice via Alleviating Oxidative Stress, Inhibiting Inflammation, and Regulating Autophagy

Acute liver injury is a worldwide problem with a high rate of morbidity and mortality, and effective pharmacological therapies are still urgently needed. Alanyl-glutamine (Ala-Gln), a dipeptide formed from L-alanine and L-glutamine, is known as a protective compound that is involved in various tissue injuries, but there are limited reports regarding the effects of Ala-Gln in acute liver injury. This present study aimed to investigate the protective effects of Ala-Gln in lipopolysaccharide (LPS)-induced acute liver injury in mice, with a focus on inflammatory responses and oxidative stress. The acute liver injury induced using LPS (50 μg/kg) and D-galactosamine (D-Gal) (400 mg/kg) stimulation in mice was significantly attenuated after Ala-Gln treatment (500 and 1500 mg/kg), as evidenced by reduced plasma alanine transaminase (ALT) (p < 0.01, p < 0.001), aspartate transaminase (AST) (p < 0.05, p < 0.001), and lactate dehydrogenase (LDH) (p < 0.01, p < 0.001) levels, and accompanied by improved histopathological changes. In addition, LPS/D-Gal-induced hepatic apoptosis was also alleviated by Ala-Gln administration, as shown by a greatly decreased ratio of TUNEL-positive hepatocytes, from approximately 10% to 2%, and markedly reduced protein levels of cleaved caspase-3 (p < 0.05, p < 0.001) in liver. Moreover, we found that LPS/D-Gal-triggered oxidative stress was suppressed after Ala-Gln treatment, the effect of which might be dependent on the elevation of SOD and GPX activities, and on GSH levels in liver. Interestingly, we observed that Ala-Gln clearly inhibited LPS/D-Gal exposure-induced macrophage accumulation and the production of proinflammatory factors in the liver. Furthermore, Ala-Gln greatly regulated autophagy in the liver in LPS/D-Gal-treated mice. Using RAW264.7 cells, we confirmed the anti-inflammatory role of Ala-Gln-targeting macrophages.

Preventive and Regenerative Effect of Glutamine and Probiotics on Gastric Mucosa in an Experimental Model of Alcohol-Induced Injury in Male Holtzman Rats

Background: The purpose of this study was to measure the preventive and regenerative effect of glutamine and probiotics induced by alcohol injury in Holtzman rats. Methods: Analytical, experimental and prospective study. The population consisted of 56 male rats between 300 and 350 g, distributed in three experimental phases: Pre-pilot phase PPP (6 rats), Pilot phase PP (10 rats), and Experimental phase EP (40 rats). In the pilot phase, 10 rats were subjected to damage with 8.5% ethanol, which was given intragastrically. The dosage was calculated for 10 rats in two groups: the first with 7.5 mL/kg in 5 rats and the second with 8.5 mL/kg in 5 rats. The experimental phase was performed in 40 rats divided into 6 groups, the negative control group (healthy), positive control group (injured), preventive experimental group (glutamine and glutamine with probiotic) and regenerative experimental group (glutamine and glutamine with probiotic). At the end of each phase, the rats were sacrificed with sodium pentobarbital (Halathal) and a portion of their stomachs was stored in formol. Results: The evaluation of stomach tissue samples (desquamation, erythema, hyperemia) showed that in the preventive phase, glutamine shows effectiveness in comparison to glutamine with probiotic. In the regenerative phase, glutamine and glutamine with probiotic did not show significant differences. Conclusions: Glutamine and probiotics can potentially serve as a therapy for the treatment for gastritis.

Effect of anaerobic resistance training on gastric emptying of solids, nutritional parameters and food behavior in the rats treated with dexamethasone

Dexamethasone (Dexa) is a potent glucocorticoid that can trigger side effects, such as neuromuscular, cardiovascular, and gastric motility disorders. Exercise can ameliorate gastrointestinal disorders. However, it is not clear whether exercise can modulate the side effects of using Dexa on gastric motility. To investigate the role of anaerobic resistance training (ART) on gastric motility and feeding behavior of rats treated with dexamethasone, rats were divided into three groups: control (Ctrl), dexamethasone (Dexa), and anaerobic resistance training + dexamethasone (ARTDexa). Anaerobic resistance training (ART) consisted of climbing a vertical ladder 5 days/week (with intensity of 50% to 100% of the maximum overload/8 weeks). At the end of the ART or control period, the rats received Dexa (1 mg/kg i.p) for 10 consecutive days. In the end, we evaluated anthropometric parameters and feeding behavior, heart rate, gastric emptying, and lipid profile in all groups. We observed significant decrease (p < 0.05) in body weight and food intake in the Dexa and ARTDexa groups compared to the control. Dexa promoted significant tachycardia (p < 0.05) and a decrease (p < 0.05) in the r-r' interval. The ART significantly prevented (p < 0.05) cardiovascular effects. Dexa induced a decrease (p < 0.05) in gastric emptying compared to the control group. On the other hand, ART significantly prevented (p < 0.05) the decrease in gastric emptying compared to Dexa. The chronic use of Dexa caused tachycardia, decreased food intake, and decreased gastric emptying. The ART modulated cardiovascular parameters, improving tachycardia. In addition, this exercise prevented gastric dysmotility induced by dexamethasone.

Moderate Physical Exercise Activates ATR2 Receptors, Improving Inflammation and Oxidative Stress in the Duodenum of 2K1C Hypertensive Rats

Background: In addition to the cardiovascular and renal systems, the gastrointestinal tract also contains angiotensin ATR_1a, ATR_1b, and ATR₂. We previously observed that the 2Kidney-1Clip hypertension model elicits physical exercise and gastrointestinal dysmotility, which is prevented by renin-angiotensin system blockers. Here, we investigate the effect of physical exercise on inflammation, stress biomarkers, and angiotensin II receptors in the duodenum of 2K1C rats. Methods: Arterial hypertension was induced by the 2K1C surgical model. The rats were allocated in Sham, 2K1C, or 2K1C+Exercise groups. One week after surgery, they were submitted to a physical exercise protocol (running 5x/week, 60min/day). Next, we assessed their intestinal contractility, cytokine levels (TNF-α, IL-1β, and IL-6), oxidative stress levels (MPO, GSH, MDA, and SOD), and the gene expression of angiotensin receptors (ATR_1A, ATR_1B, and ATR₂). Results: In comparison with the Sham group, the 2K1C arterial hypertension decreased (p<0.05) the intestinal contractility. In comparison with 2K1C, the 2K1C+Exercise group exhibited lower (p<0.05) MPO activity (22.04±5.90 vs. 78.95±18.09 UMPO/mg tissue) and higher (p<0.05) GSH concentrations in intestinal tissues (67.63±7.85 vs. 31.85±5.90mg NPSH/mg tissue). The 2K1C+Exercise group showed lower (p<0.05) cytokine levels in the intestine than 2K1C rats. In comparison with the Sham group, the 2K1C+Exercise rats showed higher (p<0.05) gene expression of ATR₂ in the duodenum. Conclusion: 2K-1C hypertension elicits an oxidative stress and inflammation process in the duodenum. Physical exercise modulates the expression twice as much of ATR2 receptors, suggesting possible anti-inflammatory and antioxidant effects induced by exercise.