Dietary Cocoa Prevents Aortic Remodeling and Vascular Oxidative Stress in Diabetic Rats

The effect of cacao bean extracts on the prevention of periodontal tissue breakdown in diabetic rats with orthodontic tooth movements

Objective

Proper management of orthodontic treatment in diabetic patients is essential due to the heightened risk of periodontal tissue breakdown associated with hyperglycemia. Cacao bean extracts (CBE) are known to reduce the inflammatory response and increase synthesis and angiogenesis in periodontitis. Therefore, this study aims to examine the effect of CBE on preventing periodontal tissue breakdown in diabetes with orthodontic force.

Methods

A total of 25 Wistar rats were divided randomly into 5 groups, including non-diabetes, diabetes, diabetes cacao 125, 250, and 500 mg/kg BW. Diabetic rats were induced with the stratified dose of Streptozotocin, and a 30-g-force from orthodontic device was applied in all groups. Diabetes cacao group was given CBE for 7 days using a gastric probe. GCF samples were used to analyze the eNOS level through the ELISA method. NFκB, Collagen-1, and FGF-2 expression were then assessed using the immunohistochemical method, while the number of fibroblasts and blood vessels was observed using hematoxylin-eosin stained tissue. The data obtained were analyzed with one-way ANOVA and post hoc tests, with p < 0.05.

Results

CBE at a dose of 250 mg/kg BW significantly increased eNOS level, Collagen-1, and FGF-2 expression, and the number of fibroblasts and blood vessels in diabetes groups. Meanwhile, the treatment decreased NFκB expression in diabetes groups (p < 0.05).

Conclusion

This study proved that CBE increased periodontal ligament synthesis and angiogenesis and decreased inflammatory response, thereby preventing periodontal tissue breakdown in diabetic rat models with tooth movement.

Synergistic Effect of a Flavonoid-Rich Cocoa-Carob Blend and Metformin in Preserving Pancreatic Beta Cells in Zucker Diabetic Fatty Rats

The loss of functional beta-cell mass in diabetes is directly linked to the development of diabetic complications. Although dietary flavonoids have demonstrated antidiabetic properties, their potential effects on pancreatic beta-cell preservation and their synergistic benefits with antidiabetic drugs remain underexplored. We have developed a potential functional food enriched in flavonoids by combining cocoa powder and carob flour (CCB), which has shown antidiabetic effects. Here, we investigated the ability of the CCB, alone or in combination with metformin, to preserve pancreatic beta cells in an established diabetic context and their potential synergistic effect. Zucker diabetic fatty rats (ZDF) were fed a CCB-rich diet or a control diet, with or without metformin, for 12 weeks. Markers of pancreatic oxidative stress and inflammation, as well as relative beta-cell mass and beta-cell apoptosis, were analyzed. Results demonstrated that CCB feeding counteracted pancreatic oxidative stress by enhancing the antioxidant defense and reducing reactive oxygen species. Moreover, the CCB suppressed islet inflammation by preventing macrophage infiltration into islets and overproduction of pro-inflammatory cytokines, along with the inactivation of nuclear factor kappa B (NFκB). As a result, the CCB supplementation prevented beta-cell apoptosis and the loss of beta cells in ZDF diabetic animals. The observed additive effect when combining the CCB with metformin underscores its potential as an adjuvant therapy to delay the progression of type 2 diabetes.

Dietary Supplementation with a Cocoa-Carob Blend Modulates Gut Microbiota and Prevents Intestinal Oxidative Stress and Barrier Dysfunction in Zucker Diabetic Rats

We have recently developed a cocoa-carob blend (CCB) rich in polyphenols with antidiabetic properties. In this study, we investigated whether its benefits could be related to gut health and gut microbiota (GM) composition and the likely phenolic metabolites involved. Zucker diabetic fatty rats were fed on a standard or a CCB-rich diet for 12 weeks. Intestinal barrier structure and oxidative and inflammatory biomarkers were analyzed in colonic samples. GM composition and phenolic metabolites were evaluated from feces. The results show that CCB improved mucin and tight-junction proteins and counteracted gut oxidative stress and inflammation by regulating sirtuin-1 and nuclear factor erythroid 2-related factor 2 (Nrf2) levels. CCB also modulated the composition of the GM, showing increases in Akkermansia and Bacteroides and decreases in Ruminococcus genera. Correlation analysis strengthened the associations between these genera and improved pathological variables in diabetic animals. Moreover, 12 phenolic metabolites were identified in CCB feces, being2,3-dihydroxybenzoic and 3,4,5-trihydroxybenzoic acids significantly associated with increased levels of Akkermansia and Oscillospira genera. Our findings support the potential use of CCB to prevent intestinal damage and dysbiosis in T2D, which would help to delay the progression of this pathology.

Nox4 as a novel therapeutic target for diabetic vascular complications

Diabetic vascular complications can affect both microvascular and macrovascular. Diabetic microvascular complications, such as diabetic nephropathy, diabetic retinopathy, diabetic neuropathy, and diabetic cardiomyopathy, are believed to be caused by oxidative stress. The Nox family of NADPH oxidases is a significant source of reactive oxygen species and plays a crucial role in regulating redox signaling, particularly in response to high glucose and diabetes mellitus. This review aims to provide an overview of the current knowledge about the role of Nox4 and its regulatory mechanisms in diabetic microangiopathies. Especially, the latest novel advances in the upregulation of Nox4 that aggravate various cell types within diabetic kidney disease will be highlighted. Interestingly, this review also presents the mechanisms by which Nox4 regulates diabetic microangiopathy from novel perspectives such as epigenetics. Besides, we emphasize Nox4 as a therapeutic target for treating microvascular complications of diabetes and summarize drugs, inhibitors, and dietary components targeting Nox4 as important therapeutic measures in preventing and treating diabetic microangiopathy. Additionally, this review also sums up the evidence related to Nox4 and diabetic macroangiopathy.

Urinary Metabolomics Study on the Protective Role of Cocoa in Zucker Diabetic Rats via 1H-NMR-Based Approach

Cocoa constitutes one of the richest sources of dietary flavonoids with demonstrated anti-diabetic potential. However, the metabolic impact of cocoa intake in a diabetic context remains unexplored. In this study, metabolomics tools have been used to investigate the potential metabolic changes induced by cocoa in type 2 diabetes (T2D). To this end, male Zucker diabetic fatty rats were fed on standard (ZDF) or 10% cocoa-rich diet (ZDF-C) from week 10 to 20 of life. Cocoa supplementation clearly decreased serum glucose levels, improved glucose metabolism and produced significant changes in the urine metabolome of ZDF animals. Fourteen differential urinary metabolites were identified, with eight of them significantly modified by cocoa. An analysis of pathways revealed that butanoate metabolism and the synthesis and degradation of branched-chain amino acids and ketone bodies are involved in the beneficial impact of cocoa on diabetes. Moreover, correlation analysis indicated major associations between some of these urine metabolites (mainly valine, leucine, and isoleucine) and body weight, glycemia, insulin sensitivity, and glycated hemoglobin levels. Overall, this untargeted metabolomics approach provides a clear metabolic fingerprint associated to chronic cocoa intake that can be used as a marker for the improvement of glucose homeostasis in a diabetic context.

Supplementation with a Cocoa-Carob Blend, Alone or in Combination with Metformin, Attenuates Diabetic Cardiomyopathy, Cardiac Oxidative Stress and Inflammation in Zucker Diabetic Rats

Diabetic cardiomyopathy (DCM) is one of the main causes of mortality among diabetic patients, with oxidative stress and inflammation major contributors to its development. Dietary flavonoids show strong antioxidant and anti-inflammatory activities, although their potential additive outcomes in combination with antidiabetic drugs have been scarcely explored. The present study investigates the cardioprotective effects of a cocoa–carob blend (CCB) diet, rich in flavonoids, alone or in combination with metformin, in the development of DCM. Zucker diabetic fatty rats (ZDF) were fed with a CCB rich-diet or a control diet, with or without metformin for 12 weeks. Glucose homeostasis, cardiac structure and function, and oxidative and inflammatory biomarkers were analysed. CCB improved glucose homeostasis, and mitigated cardiac dysfunction, hypertrophy, and fibrosis in ZDF rats. Mechanistically, CCB counteracted oxidative stress in diabetic hearts by down-regulating NADPH oxidases, reducing reactive oxygen species (ROS) generation and modulating the sirtuin-1 (SIRT1)/ nuclear factor E2-related factor 2 (Nrf2) signalling pathway, overall improving antioxidant defence. Moreover, CCB suppressed inflammatory and fibrotic reactions by inhibiting nuclear factor kappa B (NFκB) and pro-inflammatory and pro-fibrotic cytokines. Noteworthy, several of these effects were further improved in combination with metformin. Our results demonstrate that CCB strongly prevents the cardiac remodelling and dysfunction observed in diabetic animals, highlighting its potential, alone or in adjuvant therapy, for treating DCM.

Traceability of polyphenols in cocoa during the postharvest and industrialization processes and their biological antioxidant potential

Noncommunicable diseases, the leading cause of mortality around the world, are responsible for approximately 75% of premature adult deaths (ages 30-69). To tackle this issue, a healthy diet based on functional foods, including cocoa and its derivatives, has been increasingly promoted. The polyphenols present in cocoa have been of interest due to their antioxidant potential and their possible protective role in the context of noncommunicable diseases, such as diabetes and cardiovascular conditions. However, during cocoa postharvest and industrialization, the concentration of these bioactive compounds is reduced, possibly affecting their health-promoting properties. Therefore, this paper reviews in the literature in this field to find the total polyphenol content in cocoa during the postharvest and industrialization processes in order to define concentration ranges as a reference point for future research. In addition, it discusses in vitro and in vivo studies into the biological antioxidant potential of cocoa and its derivatives. This review covers publications in indexed databases from 2010 to 2020, their data were processed and presented here using box plots. As a result, we identified the concentration ranges of polyphenols depending on the type of matrix, treatment and country, as well as their relationship with the main bioactive compounds present in cocoa that are associated with their possible antioxidant biological potential and health-related benefits.

Preventive effect of cocoa flavanols against glucotoxicity-induced vascular inflammation in the arteria of diabetic rats and on the inflammatory process in TNF-α-stimulated endothelial cells

Hyperglycaemia induces a vascular inflammatory process that is a critical event in cardiovascular disease in type 2 diabetes. Cocoa and its flavanols have been widely investigated for its antioxidant and anti-inflammatory properties, and several clinical and pre-clinical studies support their vascular benefits. However, the effects of cocoa flavanols on vascular inflammation in diabetes remains to be elucidated. Herein, we evaluated the anti-inflammatory effect of a cocoa-rich diet on the aortas of Zucker diabetic fatty (ZDF) rats. Moreover, the potential role of flavanol-derived colonic metabolites to modulate the adhesion and inflammatory processes were also evaluated using TNF-α-stimulated endothelial cells. Results demonstrate that cocoa attenuates the levels of phospho-p65-nuclear factor-kappaB (NF-κB) and the expression of inflammatory factors including intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1) and inducible nitric oxide synthase in the aortas of ZDF rats. Experiments with endothelial cells further confirm that a mix of flavanol-derived colonic metabolites effectively down-regulate the levels of p-p65-NF-κB and the cell adhesion molecules ICAM-1 and VCAM-1, preventing thus the increase of monocyte-endothelial adhesion induced by TNF-α. These novel data provide the first evidence of the relevant role of cocoa and their flavanol-derived metabolites to avoid the development of endothelial inflammation and diabetic complications.