MiRNAs profile as biomarkers of nutritional therapy for the prevention of type 2 diabetes mellitus: From the CORDIOPREV study.

BACKGROUND AND AIM: The incidence of type 2 diabetes mellitus (T2DM) has increased worldwide. One of the first actions to reduce the risk of this disease is to implement healthy dietary models; however, no universal dietary strategies have so far been established. In addition, MicroRNAs (miRNAs) are emerging as new biomarkers to predict disease. We aimed to study whether miRNAs could be used to select the nutritional therapy to prevent T2DM development in patients with cardiovascular disease. METHODS: All patients from the CORDIOPREV study without T2DM at baseline according to the American Diabetes Association (ADA) diagnostic criteria (n = 462) were included in the present study. Of them, after a median dietary intervention period of 60 months with two diets (Low fat or Mediterranean diets), 107 developed T2DM and 355 subjects did not develop the disease. The plasma levels of 24 miRNAs were measured at baseline by qRT-PCR. The risk of T2DM was evaluated by Cox regression analysis based on the plasma levels of the miRNAs at baseline and according to the dietary intervention. Finally, pathways analyses were carried out to identify target genes regulated by the miRNAs studied and cellular processes which could be associated with T2DM development. RESULTS: Cox regression analyses showed that patients with low plasma levels of miR-145 at baseline showed a higher risk of developing T2DM after consumption of an LFHCC diet. In addition, patients with low levels of miR-29a, miR-28-3p and miR-126 and high plasma levels of miR-150 at baseline showed a higher risk of developing T2DM after consumption of the Med diet. Finally, pathways analysis showed an interaction of miR-126 and miR-29a in the modulation of FoxO, TNF-α, PI3K-AKT, p53 and mTOR signaling, associated with T2DM development. CONCLUSION: Our results suggest that circulating miRNAs could be used in clinical practice as a new tool for selecting the most suitable diet to prevent type 2 diabetes mellitus development in patients with cardiovascular disease. CLINICAL TRIALS NUMBER: NCT00924937.

Agaricus bisporus supplementation reduces high-fat diet-induced body weight gain and fatty liver development.

Obesity is a global epidemic characterized not only by excessive fat deposition but also by important complications such as nonalcoholic liver steatosis. Beneficial antiobesogenic effects have been described for some mushrooms. The current study aimed to demonstrate the protective effect of Agaricus bisporus (AB) supplementation against the metabolic alterations induced by high-fat-diet (HFD) feeding. Eight-week-old C57BL/6J mice were fed for 10 weeks with one of the following diets: (1) control diet (n = 7), (2) HFD (n = 7), (3) HFD supplemented with 5% AB (n = 9), and (4) HFD supplemented with 10% AB (n = 9). A pair-fed group was also included for the 10% AB group (n = 6). The impact of AB supplementation on food intake, body weight gain, and liver and fat pad weights was examined. Biochemical, histological, and molecular parameters were also analyzed. Dietary supplementation with 10% AB reduced the HFD-induced increase in body, epididymal, and mesenteric fat weights (p < 0.01, p < 0.05, and p < 0.05, respectively). Supplementation with AB also reduced liver damage in a dose-dependent manner (p < 0.01 and p < 0.001). This effect was confirmed by histological analysis that showed that liver steatosis was markedly reduced in mice fed with AB. The beneficial properties of 10% AB supplementation appear to be mediated through a decrease in food intake and via stimulation of mesenteric and hepatic free-fatty acid beta-oxidation, along with a decrease in epidydimal and hepatic expression of CD36. In conclusion, supplementation with AB prevents excessive body weight gain and liver steatosis induced by HFD consumption.

Effects of diets supplemented with MRPs from bread crust on the food intake and body weights in rats.

Traditionally the effects of dietary Maillard reaction products (MRPs) on food intake and body weight have been described in different studies, but few investigations have been conducted to analyse the main contributors responsible. We studied the effects of long-term consumption of MRPs from bread crust (BC) on rat growth, investigating the efficiency of diet and protein utilization. Different soluble and insoluble fractions of BC were studied to analyse the possible contributors. Additionally, the colour of the faecal material and the amount of fluorescent MRPs in the urine were measured in order to demonstrate MRP excretion. Six groups of rats were fed the following diets for 88 days: control (AIN-93G diet); bread dough (BD) and BC (containing 10% of BD or BC, respectively); low and high molecular weight (LMW-HMW) (containing soluble compounds from BC with <5 kDa and >5 kDa, respectively); insoluble (containing insoluble compounds from BC). Dietary MRPs tended to reduce the food intake and body weight significantly after consumption of more complex compounds (HMW and insoluble). The L*-value in the faeces decreased in animals fed BC and its derivatives, providing evidence of the presence of MRPs. The fluorescence associated with MRP excretion in urine was higher when the LMW diet was consumed, suggesting the easier absorption and clearance of the smaller compounds of BC.

Influence of bread crust-derived Maillard reaction products on phosphorus balance in rats.

BACKGROUND: Maillard reaction products (MRP) improve food palatability and are linked to some positive biological actions. However, diverse negative consequences, some related to protein damage and mineral availability, have been established. AIM OF STUDY: We investigated the effects of MRP, from a bread crust diet, on phosphorus bioavailability and tissue distribution in rats to determine whether these effects are related to the molecular weight of browning products. METHODS: During a study period of 88 days, rats were fed either a control diet or one of the following: with bread crust as a source of MRP, or one with its soluble high molecular weight, soluble low molecular weight or insoluble fraction (bread crust, HMW, LMW and insoluble diets, respectively). In the final week, a phosphorus balance was performed, after which the animals were sacrificed and some organs removed to analyse phosphorus content. A second balance was carried out throughout the experimental period to calculate phosphorus retention. RESULTS: Phosphorus balance in the last week was unchanged. However, considering the whole experimental period, a trend towards improved bioavailability, significant in the HMW group, was observed. Higher phosphorus concentrations were measured in the small intestine and bone. CONCLUSIONS: The consumption of MRP derived from bread did not alter phosphorus retention, due to increased bioavailability, especially concerning HMW compounds. The overall phosphorus body content remained unchanged and there were no changes in the bone, its principal metabolic destination. However, MRP consumption markedly raised phosphorus levels at the digestive level, especially when consumed as isolate fractions. The slower rate of stomach emptying is assumed to be related to this effect.