Postprandial glucose-lowering effect of cagaita (Eugenia dysenterica DC) fruit juice in dysglycemic subjects with metabolic syndrome: An exploratory study

Cocoa-carob blend acute intake modifies miRNAs related to insulin sensitivity in type 2 diabetic subjects: a randomised controlled nutritional trial

Postprandial metabolic disturbances are exacerbated in type 2 diabetes (T2D). Cocoa and carob, despite showing promising effects on these alterations in preclinical studies, have not yet been jointly tested in a clinical trial. Therefore, this acute, randomised, controlled, crossover nutritional trial evaluated the postprandial effects of a cocoa-carob blend (CCB) in participants with T2D (n = 20) and overweight/obesity. The subjects followed three treatments: hypercaloric breakfast (high-sugar and high-saturated fat, 900 kcal) as the control (treatment C); the same breakfast together with 10 g of the CCB, with 5.6 g of dietary fibre and 1.6 g of total polyphenols (treatment A); and the same breakfast after consuming the CCB (10 g) the night before (treatment B). Various analyses were performed, including the determination of the clinical markers of T2D (fasting and postprandial glucose and insulin, GLP-1, and glycaemic profile), satiety evaluation, analysis of exosomal miRNA expression and ex vivo determination of inflammation modulation. No effect on glucose homeostasis (glucose, insulin, and GLP-1) was found in the study population. However, eight exosomal miRNAs were found to be significantly modified owing to CCB supplementation compared with treatment C, with three of them (miR-20A-5p, miR-23A-3p, and miR-17-5p) associated with an improvement in insulin sensitivity. Furthermore, the CCB caused a decrease in hunger feelings (0-120 min), as assessed by the visual analogue scale (VAS). Finally, treatment A caused a significant decrease in the glucose increment within 0-30 min of treatment in subjects with overweight. No significant modifications were found in the other assessed parameters. The acute intake of the CCB by subjects with T2D showed modest although significant results, which need to be validated in a long-term randomised controlled trial.

Native Brazilian fruits: postprandial glycemic control and carbohydrate-enzyme inhibition - insights from a randomized crossover clinical trial

Brazilian native fruits are excellent sources of polyphenols, especially berries, which are rich in anthocyanins. These compounds are associated with improvements in the insulin signaling pathway, reduced glucose absorption, and the inhibition of carbohydrate-digesting enzymes. This study aimed to evaluate the impact of consuming native fruits, including grumixama (GM), Rio Grande cherry (RGc), and uvaia (UV), on the 2-hour postprandial glucose, plasma insulin, and inflammatory responses in healthy individuals. No study has evaluated the effects of these fruits on carbohydrate-digesting enzymes alongside glucose transporters. This was assessed using two methods: (i) post-bread glycemic response and (ii) post-glucose glycemic response. Healthy volunteers participated in a crossover study with control, consuming juices from GM, RGc, UV, or water, followed by white bread or a glucose solution. Capillary glucose, plasma insulin, and pro-inflammatory cytokine levels were measured. Additionally, the inhibitory activities of α-amylase and α-glucosidase by fruit extracts were evaluated in vitro. Molecular docking assessed the affinity of individual anthocyanins and flavonols. Cyanidin 3-glucoside was identified as the predominant flavonoid in GM and RGc, while quercetin 3-galactoside and rutin were the primary flavonols in GM and RGc, respectively. RGc juice significantly reduced 2-hour postprandial glucose levels, and juices rich in anthocyanins delayed the glucose peak to 45 minutes. Only GM juice delayed the insulin peak. Phenolic extracts from GM and RGc inhibited α-amylase and α-glucosidase activities in vitro. In silico analysis showed high-affinity binding of anthocyanins and flavonols found in the GM and RGc extracts to both enzymes. Therefore, GM and RGc may be considered beneficial foods and serve as additional nutritional supplements in managing postprandial hyperglycemia.

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.

Underexploited Brazilian Cerrado fruits as sources of phenolic compounds for diseases management: A review

The Brazilian Cerrado is home to a large number of native and endemic species of enormous potential, among which we can highlight the cagaita, gabiroba, jatobá-do-cerrado, lobeira, and mangaba. In this review, we report the nutritional and phenolic composition, as well as bioactivities of these five Brazilian Cerrado fruits. The compiled data indicated that these fruits have high nutritional, functional, and economic potential and contribute to the daily intake of macro- and micronutrients, energy, and phenolic compounds by inhabitants of the Cerrado region. Phenolic-rich extracts obtained from these fruits have shown several bioactivities, including antioxidant, anti-inflammatory, antidyslipidemic, antidiabetic, analgesic, anticarcinogenic, hepatoprotective, gastrointestinal protective, and antimicrobial properties. Therefore, these fruits can be explored by the food industry as a raw material to develop food products of high value-added, such as functional foods, and can also be employed as plant sources to obtain bioactive compounds for food, cosmetic, and pharmaceutical purposes.

Urolithins: a Comprehensive Update on their Metabolism, Bioactivity, and Associated Gut Microbiota

Urolithins, metabolites produced by the gut microbiota from the polyphenols ellagitannins and ellagic acid, are discovered by the research group in humans almost 20 years ago. Pioneering research suggests urolithins as pleiotropic bioactive contributors to explain the health benefits after consuming ellagitannin-rich sources (pomegranates, walnuts, strawberries, etc.). Here, this study comprehensively updates the knowledge on urolithins, emphasizing the review of the literature published during the last 5 years. To date, 13 urolithins and their corresponding conjugated metabolites (glucuronides, sulfates, etc.) have been described and, depending on the urolithin, detected in different human fluids and tissues (urine, blood, feces, breastmilk, prostate, colon, and breast tissues). There has been a substantial advance in the research on microorganisms involved in urolithin production, along with the compositional and functional characterization of the gut microbiota associated with urolithins metabolism that gives rise to the so-called urolithin metabotypes (UM-A, UM-B, and UM-0), relevant in human health. The design of in vitro studies using physiologically relevant assay conditions (molecular forms and concentrations) is still a pending subject, making some reported urolithin activities questionable. In contrast, remarkable progress has been made in the research on the safety, bioactivity, and associated mechanisms of urolithin A, including the first human interventions.

Profiling the Effect of Targeting Wild Isocitrate Dehydrogenase 1 (IDH1) on the Cellular Metabolome of Leukemic Cells

Leukemia is one of the most common primary malignancies of the hematologic system in both children and adults and remains a largely incurable or relapsing disease. The elucidation of disease subtypes based on mutational profiling has not improved clinical outcomes. IDH1/2 are critical enzymes of the TCA cycle that produces α-ketoglutarate (αKG). However, their mutated version is well reported in various cancer types, including leukemia, which produces D-2 hydroxyglutarate (D-2HG), an oncometabolite. Recently, some studies have shown that wild-type IDH1 is highly expressed in non-small cell lung carcinoma (NSCLC), primary glioblastomas (GBM), and several hematological malignancies and is correlated with disease progression. This work shows that the treatment of wild-type IDH1 leukemia cells with a specific IDH1 inhibitor shifted leukemic cells toward glycolysis from the oxidative phosphorylation (OXPHOS) phenotype. We also noticed a reduction in αKG in treated cells, possibly suggesting the inhibition of IDH1 enzymatic activity. Furthermore, we found that IDH1 inhibition reduced the metabolites related to one-carbon metabolism, which is essential for maintaining global methylation in leukemic cells. Finally, we observed that metabolic alteration in IDH1 inhibitor-treated leukemic cells promoted reactive oxygen species (ROS) formation and the loss of mitochondrial membrane potential, leading to apoptosis in leukemic cells. We showed that targeting wild-type IDH1 leukemic cells promotes metabolic alterations that can be exploited for combination therapies for a better outcome.

Effect of Acute Intake of Fermented Orange Juice on Fasting and Postprandial Glucose Metabolism, Plasma Lipids and Antioxidant Status in Healthy Human

Higher postprandial plasma glucose and lipemia, and oxidative and inflammatory responses, are considered important cardiovascular risk factors. Fermentation of fruits has generated products with high concentrations of bioactive compounds. The aim of this study was to evaluate the potential acute effects that fermented orange juice (FOJ) can exert in healthy humans by modulating postprandial response, and inflammatory/antioxidant status, compared with orange juice (OJ). Nine volunteers were recruited for a randomized, controlled, and crossover study. Participants ingested 500 mL of FOJ. At 4 h post intake, subjects consumed a standardized mixed meal. Blood samples were collected at 0-8 h hours post intake. The subjects repeated the protocol with OJ following a 2-week washout period. Glucose and lipid metabolism, plasma antioxidant capacity (ORAC, FRAP), endogenous antioxidants (albumin, bilirubin, uric acid), C-reactive protein and fibrinogen were measured in plasma samples. There was a trend of a smaller increase in LDL-C after FOJ intake compared with OJ, a significant decrease in apo-B and significant increase in ORAC. The glycemic and triglyceride response of meal was attenuated with FOJ. No differences were obtained in endogenous antioxidants and inflammation status between the treatments. The acute consumption of FOJ could play a protective role against cardiovascular risk factors.

Reinforcing the bulwark: unravelling the efficient applications of plant phenolics and tannins against environmental stresses

Phenolic compounds are plant secondary metabolites that play a vital role in plant resistance. They are mainly synthetized from the amino acid L-phenylalanine, which is converted to trans-cinnamic acid in a series of biochemical reactions. These compounds take part in the regulation of seed germination and cooperate in regulating the growth of plants, also taking part in defense responses during infection, UV exposure, injuries, and heavy metal stress. The aim of this review is to discuss the role of phenolic compounds in the interactions of plants with various stress factors, both biotic and abiotic with special attention to their antioxidant properties. Therefore, understanding the biochemical potential of the phenylpropanoid derivatives would be beneficial in sustaining the metabolic processes used by plants to thrive and endure under adverse conditions.

Pharmacology and toxicology of tannins

Tannins are an interesting class of polyphenols, characterized, in almost all cases, by a different degree of polymerization, which, inevitably, markedly influences their bioavailability, as well as biochemical and pharmacological activities. They have been used for the process of tanning to transform hides into leather, from which their name derives. For several time, they have not been accurately evaluated, but now researchers have started to unravel their potential, highlighting anti-inflammatory, antimicrobial, antioxidant and anticancer activities, as well as their involvement in cardiovascular, neuroprotective and in general metabolic diseases prevention. The mechanisms underlying their activity are often complex, but the main targets of their action (such as key enzymes modulation, activation of metabolic pathways and changes in the metabolic fluxes) are highlighted in this review, without losing sight of their toxicity. This aspect still needs further and better-designed study to be thoroughly understood and allow a more conscious use of tannins for human health.

Urolithin A and B Alter Cellular Metabolism and Induce Metabolites Associated with Apoptosis in Leukemic Cells

Leukemia is persistently a significant cause of illness and mortality worldwide. Urolithins, metabolites of ellagic acid and ellagitannins produced by gut microbiota, showed better bioactive compounds liable for the health benefits exerted by ellagic acid and ellagitannins containing pomegranate and walnuts. Here, we assessed the potential antileukemic activities of both urolithin A and urolithin B. Results showed that both urolithin A and B significantly inhibited the proliferation of leukemic cell lines Jurkat and K562, among which urolithin A showed the more prominent antiproliferative capability. Further, urolithin treatment alters leukemic cell metabolism, as evidenced by increased metabolic rate and notable changes in glutamine metabolism, one-carbon metabolism, and lipid metabolism. Next, we evidenced that both urolithins equally promoted apoptosis in leukemic cell lines. Based on these observations, we concluded that both urolithin A and B alter leukemic cell metabolome, resulting in a halt of proliferation, followed by apoptosis. The data can be used for designing new combinational therapies to eradicate leukemic cells.