Distinct Impact of Natural Sugars from Fruit Juices and Added Sugars on Caloric Intake, Body Weight, Glycaemia, Oxidative Stress and Glycation in Diabetic Rats

Host-diet-microbiota interplay in intestinal nutrition and health

The intestine is populated by a complex and dynamic assortment of microbes, collectively called gut microbiota, that interact with the host and contribute to its metabolism and physiology. Diet is considered a key regulator of intestinal microbiota, as ingested nutrients interact with and shape the resident microbiota composition. Furthermore, recent studies underscore the interplay of dietary and microbiota-derived nutrients, which directly impinge on intestinal stem cells regulating their turnover to ensure a healthy gut barrier. Although advanced sequencing methodologies have allowed the characterization of the human gut microbiome, mechanistic studies assessing diet-microbiota-host interactions depend on the use of genetically tractable models, such as Drosophila melanogaster. In this review, we first discuss the similarities between the human and fly intestines and then we focus on the effects of diet and microbiota on nutrient-sensing signaling cascades controlling intestinal stem cell self-renewal and differentiation, as well as disease. Finally, we underline the use of the Drosophila model in assessing the role of microbiota in gut-related pathologies and in understanding the mechanisms that mediate different whole-body manifestations of gut dysfunction.

New Therapeutic Strategies for Obesity and Its Metabolic Sequelae: Brazilian Cerrado as a Unique Biome

Brazil has several important biomes holding impressive fauna and flora biodiversity. Cerrado being one of the richest ones and a significant area in the search for new plant-based products, such as foods, cosmetics, and medicines. The therapeutic potential of Cerrado plants has been described by several studies associating ethnopharmacological knowledge with phytochemical compounds and therapeutic effects. Based on this wide range of options, the Brazilian population has been using these medicinal plants (MP) for centuries for the treatment of various health conditions. Among these, we highlight metabolic diseases, namely obesity and its metabolic alterations from metabolic syndrome to later stages such as type 2 diabetes (T2D). Several studies have shown that adipose tissue (AT) dysfunction leads to proinflammatory cytokine secretion and impaired free fatty acid (FFA) oxidation and oxidative status, creating the basis for insulin resistance and glucose dysmetabolism. In this scenario, the great Brazilian biodiversity and a wide variety of phytochemical compounds make it an important candidate for the identification of pharmacological strategies for the treatment of these conditions. This review aimed to analyze and summarize the current literature on plants from the Brazilian Cerrado that have therapeutic activity against obesity and its metabolic conditions, reducing inflammation and oxidative stress.

Development of a functional prebiotic strawberry preparation by in situ enzymatic conversion of sucrose into fructo-oligosaccharides

Food industry has been pressed to develop products with reduced sugar and low caloric value, while maintaining unchanged their rheological and physicochemical properties. The development of a strawberry preparation for the dairy industry, with prebiotic functionality, was herein investigated by in situ conversion of its intrinsic sucrose content into prebiotic fructo-oligosaccharides (FOS). Two commercial enzymatic complexes, Viscozyme® L and Pectinex® Ultra SP-L, were evaluated for the synthesis of FOS. Operational parameters such as temperature, pH, and enzyme:substrate ratio (E:S) were optimized to maximize FOS yield. The rheological and physicochemical properties of the obtained strawberry preparation were evaluated. For functional analysis, the resistance of FOS to the harsh conditions of the gastro-intestinal digestion was evaluated by applying the standardized INFOGEST static protocol. At optimal conditions (60 ℃, pH 5.0), Pectinex® produced 265 ± 3 g·L^-1 FOS, yielding 0.57 ± 0.01 g_FOS·g_{initial sucrose}^-1 after 7 h reaction (E:S:1:40); and Viscozyme® produced 295 ± 1 g·L^-1 FOS, yielding 0.66 ± 0.00 g_FOS·g_{initial sucrose}^-1 after 5 h (E:S:1:30). The obtained strawberry preparations contained more than 50 %(w/w) prebiotic FOS incorporated (DP 3-5), with 80 % reduction of its sucrose content. The caloric value was therefore reduced by 26-31 %. FOS showed resistance to gastrointestinal digestion being only slightly hydrolysed (<10 %). 1^F-Fructofuranosylnystose was not digested at any phase of the digestion. Although the physicochemical properties of the prebiotic preparations were different from the original one, parameters such as the lower °Brix, water activity, consistency and viscosity, and its different color, may be easily adjusted. Results indicate that in situ synthesis strategies are efficient alternatives in the manufacture of reduced sugar and low-caloric food products with prebiotic potential.

Improvement of Glycaemia and Endothelial Function by a New Low-Dose Curcuminoid in an Animal Model of Type 2 Diabetes

Curcumin has been suggested as a promising treatment for metabolic diseases, but the high doses required limit its therapeutic use. In this study, a new curcuminoid is synthesised to increase curcumin anti-inflammatory and antioxidant potential and to achieve hypoglycaemic and protective vascular effects in type 2 diabetic rats in a lower dose. In vitro, the anti-inflammatory effect was determined through the Griess reaction, and the antioxidant activity through ABTS and TBARS assays. In vivo, Goto-Kakizaki rats were treated for 2 weeks with the equimolar dose of curcumin (40 mg/kg/day) or curcuminoid (52.4 mg/kg/day). Fasting glycaemia, insulin tolerance, plasma insulin, insulin signalling, serum FFA, endothelial function and several markers of oxidative stress were evaluated. Both compounds presented a significant anti-inflammatory effect. Moreover, the curcuminoid had a marked hypoglycaemic effect, accompanied by higher GLUT4 levels in adipose tissue. Both compounds increased NO-dependent vasorelaxation, but only the curcuminoid exacerbated the response to ascorbic acid, consistent with a higher decrease in vascular oxidative and nitrosative stress. SOD1 and GLO1 levels were increased in EAT and heart, respectively. Altogether, these data suggest that the curcuminoid developed here has more pronounced effects than curcumin in low doses, improving the oxidative stress, endothelial function and glycaemic profile in type 2 diabetes.