Intermittent fasting associated with coconut oil (Cocos nucifera L.) alters gut-liver axis parameters in diet-induced obese rats.

OBJECTIVE: The aim of this article is to investigate the effect of intermittent fasting, associated or not with coconut oil intake, on the gut-liver axis of obese rats. METHODS: A total of 50 rats were divided into five groups: control, obese, obese with intermittent fasting, obese with intermittent fasting plus coconut oil, and obese with caloric restriction. The rats were induced to obesity with a high-sugar diet for 17 wk. The respective interventions were carried out in the last 4 wk. RESULTS: The groups with intermittent fasting protocols had reduced total cholesterol (on average 54.31%), low-density lipoprotein (on average 53.39%), and triacylglycerols (on average 23.94%) versus the obese group; and the obese with intermittent fasting plus coconut oil group had the highest high-density lipoprotein compared with all groups. The obese with intermittent fasting plus coconut oil and obese with caloric restriction groups had lower metabolic load compared with the other groups. The obese group had high citric and succinic acid concentrations, which affected the hepatic tricarboxylic acid cycle, while all the interventions had reduced concentrations of these acids. No histologic changes were observed in the intestine or liver of the groups. CONCLUSION: Intermittent fasting, especially when associated with coconut oil, had effects comparable with caloric restriction in modulating the parameters of the gut-liver axis.

Antioxidant potential of acerola by-product along the enterohepatic axis of rats fed a high-fat diet.

Acerola (Malpighia emarginata DC) by-product (ABP) has bioactive compounds that can provide antioxidant and hypolipidemic effects in vivo. In this study we aimed to evaluate the antioxidant potential of ABP on oxidative damage along the enterohepatic axis of rats fed a high-fat diet for 7 weeks. In addition, we analysed the phenolic compound profile in the enterohepatic axis, and the lipid accumulation in the liver, colon and liver tissue structure of high-fat diet-fed rats treated with fenofibrate drug (100 mg/kg) or ABP (400 mg/kg) via orogastric administration in the 4th to 7th weeks of the experiment. ABP had increased antioxidant potential in vitro and presented ascorbic acid (2022.06 µg/g), carotenoid (2.63 µg/g), and total phenolic compound (5366.44 µg/g) contents. The high-fat diet-fed rats that received ABP (compared to fenofibrate treatment) presented a non-significant reduction of 9.87% in guanine oxidation product, lower relative liver weight, degree of hepatic steatosis, and aspartate aminotransferase level in their blood. ABP also provided high-fat diet-fed rats: an increased amount of total phenolic compounds in caecal digesta (946.42 µg/g), faeces (3299.07 µg/g), colon (256.15 µg/g) and hepatic tissues (454.80 µg/g); higher total antioxidant capacity in plasma and colon; and lower lipid peroxidation in plasma, colonic and hepatic tissues. The results point to the potential antioxidant activity of ABP against oxidative damage along the enterohepatic axis caused by high-fat diet intake. The ABP had a greater protective effect on the healthy liver compared to fenofibrate treatment due to its bioactive compound content.

Effects of supplementation of tropical fruit processing by-products on lipid profile, retinol levels and intestinal function in Wistar rats.

Fruits agro-industrial by-products may have a great variety of bioactive compounds that promote health. Thus, the effects of supplementation with acerola, cashew and guava processing by-products for 28 days on retinol level, lipid profile and on some aspects related to intestinal function in rats were investigated. The animals supplemented with different fruit by-products presented similar weight gain, faecal pH values and intestinal epithelial structures; however, they showed higher moisture and Lactobacillus spp. and Bifidobacterium spp. counts in faeces compared to the control group. Supplementation with the cashew by-product decreased the blood glucose, acerola and guava by-products reduced serum lipid levels and all fruit by-products tested increased serum and hepatic retinol. The results indicated that acerola and guava by-products possess a potential hypolipidemic effect. The three fruit by-products increase the hepatic retinol deposition and the faecal populations of beneficial bacterial groups and modulated aspects of intestinal function. The findings of this study can contribute to sustainable fruticulture and support future clinical studies with the supplementation of by-products.

Nutritional Characterization, Antioxidant, and Lipid-Lowering Effects of Yellow Mombin (Spondias mombin) Supplemented to Rats Fed a High-Fat Diet.

The aim of this study was to evaluate the effects of supplementing yellow mombin (YM) on the oxidative, somatic, and lipid parameters in rats fed a high-fat diet. A total of 24 adult Wistar rats were randomized into three groups: normal-fat diet (NF), high-fat diet (HF), and high-fat diet with YM supplementation (HFYM). Diets were administered for four weeks, and YM (400 mg/kg) was supplemented via gavage in the last two weeks of the experiment. After the four-week period, the somatic, serum biochemical, and liver oxidative parameters were evaluated. YM has a high antioxidant activity and significant amounts of phenolic compounds, carotenoids, vitamin C, dietary fibre, and minerals. The HFYM group had the lowest body weight (18.75%), body mass index (17.74%), and adiposity (31.63%) compared with the HF group. YM supplementation reduced low-density lipoprotein by 43.05% and increased high-density lipoprotein by 25.73%, but did not improve the triglyceride levels in the serum. YM treatment improved glucose tolerance and lipid peroxidation, and also enhanced the antioxidant capacity, superoxide dismutase, and glutathione peroxidase activities in the liver. These results indicate the lipid-lowering property and potential antioxidant activity of YM against liver oxidative damage caused by a high-fat diet intake, which may be associated with the bioactive compounds present in this fruit.

Functional and morphologic dysfunctions in the airways of rats submitted to an experimental model of obesity-exacerbated asthma.

The obesity-exacerbated asthma phenotype is characterized by more severe asthma symptoms and glucocorticoid resistance. The aim of this study was to standardize an obesity-exacerbated asthma model by a high glycemic level index (HGLI) diet and ovalbumin (OVA) sensitization and challenges in Wistar rats. Animals were divided into groups: control (Ctrl), obese (Ob), asthmatic (Asth), obese asthmatic (Ob + Asth) and obese asthmatic treated with dexamethasone (Ob + Asth + Dexa), and in vivo and in vitro functional and morphological parameters were measured. After HGLI consumption, there was an increase in body weight, fasting blood glucose, abdominal circumferences, body mass index and adiposity index. Respiratory function showed a reduction in pulmonary tidal volume and ventilation. In isolated tracheas, carbachol showed an increase in contractile efficacy in the Ob, Ob + Asth and Ob + Asth + Dexa, but mostly on Ob + Asth. Histological analysis of lungs showed peribronchovascular inflammation and smooth muscle hypertrophy and extracellular remodeling on Ob + Asth and Ob + Asth + Dexa. An obesity-exacerbated asthma model was successfully established. Therefore, this model allows further molecular investigations and the search for new therapies for the treatment and relief of symptoms of patients with obesity-induced resistant asthma.

Does intermittent fasting associated with aerobic training influence parameters related to the gut-brain axis of Wistar rats?

BACKGROUND: Intermittent fasting (IF) and aerobic training have demonstrated beneficial effects on intestinal microbiota composition, but little is known about benefits to the brain through the gut-brain axis. The present study aimed to evaluate gut-brain axis parameters in Wistar rats submitted to IF associated or not with aerobic training. METHODS: Male rats were evaluated for training performance and then randomized into 4 groups of ten: sedentary control (SC), trained control (TC), sedentary intermittent fasting (SIF), and trained intermittent fasting (TIF), and evaluated during four weeks. RESULTS: The adiposity index was similar among the TC (2.15±0.43%), SIF (1.98±0.69%) and TIF (1.86±0.51%) groups, and differed from SC (2.98±0.80%). TIF had lower counts of lactic acid bacteria, while SIF had higher counts of Bifidobacterium and Enterococcus. TIF had the highest amount of formic acid in faeces (44.44±2.40 µmol/g) and lowest amount of succinic acid in the gut (0.38±0.00 µmol/g), while SIF had the highest propionic acid amount in the faeces (802.80±00.33 µmol/g) and the lowest amount of lactic acid in the gut (0.85±0.00 µmol/g). TIF demonstrated a tendency towards an anxiolytic effect and SIF showed potential antidepressant effect. IF caused different brain and intestinal injuries. TIF rats presented a diffuse and intense marking of IL-1ß in the hippocampus. CONCLUSION: IF and aerobic exercise, associated or not, can modulate parameters related to the gut-brain axis of Wistar rats, and some benefits may be related to the amounts of organic acids.

Modulation of vascular function and anti-aggregation effect induced by (1→3) (1→6)-ß-d-glucan of Saccharomyces cerevisiae and its carboxymethylated derivative in rats.

BACKGROUND: ß-d-Glucans are polysaccharides found in the cell walls of yeasts, such as Saccharomyces cerevisiae, and they have been studied because of their beneficial effects on health, mainly in terms of immunomodulation. However, information on the action of these polymers on vascular and platelet function is still scarce. This study evaluate the effect of (1→3) (1→6) ß-d-glucan (ßG-Sc) and its carboxymethylated derivative (CM-G) on vascular and platelet function in rats. METHODS: The animals received daily oral treatments with ßG-Sc (20mg/kg) and CM-G (20mg/kg) for eight days. Next, cytokine quantification, vascular reactivity and adenosine diphosphate (ADP)- and collagen-induced platelet aggregation studies were performed. In vitro platelet aggregation and P-selectin exposition assays were conducted using 100 and 300µg/mL CM-G. RESULTS: The CM-G-treated group had less IL-8 than did the control. In reactivity experiments, CM-G and ßG-Sc treatments did not change the contractile response of the vessel induced by PHE. Moreover, only CM-G improved the vasorelaxation response to Nitroprusside (SPN, a nitric oxide donor). The in vitro aggregation studies showed that at the highest concentration (300µg/mL), CM-G inhibited the agonist-induced platelet aggregation with an effect similar to that of acetylsalicylic acid and without affecting P-selectin exposition. The treatments with ßG-Sc or CM-G inhibited the platelet aggregation stimulated by ADP, but only ßG-Sc treatment was effective in affect the collagen-stimulated aggregation. CONCLUSIONS: These findings suggest that CM-G modulate positively the vascular function, mainly in responses NO-dependent. CM-G and ßG-Sc have an anti-aggregation effect, being CM-G more selective to ADP-induced platelet aggregation.