Use of dark chocolate for diabetic patients: a review of the literature and current evidence

A review of air pollution as a driver of cardiovascular disease risk across the diabetes spectrum

The prevalence of diabetes is estimated to reach almost 630 million cases worldwide by the year 2045; of current and projected cases, over 90% are type 2 diabetes. Air pollution exposure has been implicated in the onset and progression of diabetes. Increased exposure to fine particulate matter air pollution (PM2.5) is associated with increases in blood glucose and glycated hemoglobin (HbA1c) across the glycemic spectrum, including normoglycemia, prediabetes, and all forms of diabetes. Air pollution exposure is a driver of cardiovascular disease onset and exacerbation and can increase cardiovascular risk among those with diabetes. In this review, we summarize the literature describing the relationships between air pollution exposure, diabetes and cardiovascular disease, highlighting how airborne pollutants can disrupt glucose homeostasis. We discuss how air pollution and diabetes, via shared mechanisms leading to endothelial dysfunction, drive increased cardiovascular disease risk. We identify portable air cleaners as potentially useful tools to prevent adverse cardiovascular outcomes due to air pollution exposure across the diabetes spectrum, while emphasizing the need for further study in this particular population. Given the enormity of the health and financial impacts of air pollution exposure on patients with diabetes, a greater understanding of the interventions to reduce cardiovascular risk in this population is needed.

Aldose Reductase and Protein Glycation Inhibitory Activity of Dark Chocolate-Assisted Zinc Oxide Nanoparticles

Introduction One of the most common health issues that the global population is dealing with is the associated complications of diabetes, which encompasses cataracts, peripheral neuropathy, vascular damage, impaired wound healing, retinal issues, and arterial wall stiffening. The present study is aimed to evaluate the effect of dark chocolate and its assisted zinc oxide nanoparticles against diabetes-associated complications. Materials and methods Zinc oxide nanoparticles were synthesized using commercially dark chocolate (DC-ZnO NP). The synthesized DC-ZnO NPs were evaluated against recombinant aldose reductase (AR) activity and the formation of advanced glycation end products (AGEs). Aminoguanidine and gallic acid were used as reference standards for AGE assay and sorbitol accumulation inhibition, respectively. Results The results of the present study showed that green synthesized DC-ZnO NP had a significant dose-dependent inhibitory activity on both AR and AGEs. The inhibitory activity was compared to that of quercetin and aminoguanidine, respectively. Conclusion Targeting the endogenous antioxidant systems like AGEs and AR enzymes seems to provide a promising therapeutic approach, thus concluding that ZnO-NP could be a promising agent for treating diabetes-related complications such as diabetic retinopathy, diabetic nephropathy, and diabetic neuropathy that provide grounds for further clinical investigations and trials.

The impact of different dark chocolate dietary patterns on synaptic potency and plasticity in the hippocampal CA1 area of the rats under chronic isolation stress

INTRODUCTION

Although, stress causes brain dysfunction, consumption of dark chocolate (DC) has positive effects on brain functions. The current study investigated the impact of different DC dietary patterns on synaptic potency and plasticity in the hippocampal CA1 area, as well as food intake and body weight in rats under chronic isolation stress.

METHODS

Thirty-five rats were allocated into five groups of control, stress, and stress accompanied by three DC dietary patterns (stress-compulsory, -optional, and -restricted DC). The stressed rats on a compulsory diet only received DC and the ones on an optional diet received unlimited chow and/or DC. Also, the stressed rats on a restricted diet each received chow freely and only 4 g DC daily. Subsequently, the slope and amplitude of field excitatory postsynaptic potentials (fEPSPs) were assessed based on the Input-Output (I/O) curves and after the longterm potentiation (LTP). Moreover, food intake and body weight were measured for all groups.

RESULTS

The fEPSP slope and amplitude in the I/O curves and after LTP decreased significantly in the stress group compared to the control group. Although the slope and amplitude both enhanced non-significantly in the optional DC diet, these parameters changed significantly in both compulsory and restricted DC dietary patterns compared to the stress group. Also, food intake and body weight decreased significantly in all DC groups.

CONCLUSION

The compulsory and restricted DC dietary patterns reversed the harmful effects of chronic isolation stress on the hippocampal synaptic potency, plasticity, learning, and memory. All DC diets, especially compulsory and restricted ones, reduced food intake and body weight.

Role of dietary polyphenols on gut microbiota, their metabolites and health benefits

The beneficial health roles of dietary polyphenols in preventing oxidative stress related chronic diseases have been subjected to intense investigation over the last two decades. As our understanding of the role of gut microbiota advances our knowledge of the antioxidant and anti-inflammatory functions of polyphenols accumulates, there emerges a need to examine the prebiotic role of dietary polyphenols. This review focused onthe role of different types and sources of dietary polyphenols on the modulation of the gut microbiota, their metabolites and how they impact on host health benefits. Inter-dependence between the gut microbiota and polyphenol metabolites and the vital balance between the two in maintaining the host gut homeostasis were discussed with reference to different types and sources of dietary polyphenols. Similarly, the mechanisms behind the health benefits by various polyphenolic metabolites bio-transformed by gut microbiota were also explained. However, further research should focus on the importance of human trials and profound links of polyphenols-gut microbiota-nerve-brain as they provide the key to unlock the mechanisms behind the observed benefits of dietary polyphenols found in vitro and in vivo studies.

Effect of cacao polyphenol-rich chocolate on postprandial glycemia, insulin, and incretin secretion in healthy participants

OBJECTIVES

There is substantial interest in using dark chocolate to prevent postprandial hyperglycemia. We investigated the effects of cacao polyphenol-rich chocolate on postprandial glycemic and insulinemic responses and whether cacao polyphenol-rich chocolate increases glucagon-like peptide-1 (GLP-1) secretion.

METHODS

In a stratified, randomized, crossover study, 48 healthy participants ingested either water (W) or cacao polyphenol-rich chocolate plus water (C) 15 min before a 50 g oral glucose tolerance test (OGTT). Pre- and postprandial concentrations of blood glucose, insulin, free fatty acid, glucagon, and GLP-1 were evaluated.

RESULTS

Peak plasma glucose concentrations did not differ significantly between groups W and C; however, plasma glucose concentrations at 120 min in group C were significantly lower than those in group W (P < .01). Postprandial serum insulin and plasma GLP-1 concentrations and incremental serum insulin and plasma GLP-1 area under the curve (AUC)_{-15-180 min} for group C were significantly higher than those for group W (P < .05). When comparing the changes after the OGTT, the incremental plasma glucose AUC_{0-180 min} for group C was significantly lower than that for group W (P < .05), but the incremental serum insulin and plasma GLP-1 AUC_{0-180 min} did not differ significantly between groups W and C.

CONCLUSIONS

This study indicated that the intake of cacao polyphenol-rich chocolate before a 50 g OGTT could enhance early insulin and GLP-1 secretion in healthy participants, and illustrates the potential of cacao polyphenol-rich chocolate in managing postprandial glucose excursions.

The effects of pilates and flavanol-rich dark chocolate consumption on the total antioxidant capacity, glycemic control and BMI in diabetic females with neuropathy complications

BACKGROUND

Pilates is a type of exercise recommended to diabetic patients due to its health benefits. Dark chocolate is also well known for its antioxidant properties. The purpose of this study has been to compare the effects of regular Pilates and flavanol-rich dark chocolate consumption on the total antioxidant capacity (TAC), fasting blood glucose (FBG) and BMI in diabetic females with peripheral neuropathy complications.

METHODS

36 diabetic patients enrolled in this single-blinded clinical trial. They were randomly allocated to the control (n = 12), Pilates and dark chocolate intake (n = 12), and Pilates and flavanol-free white chocolate (n = 12) groups. Two Pilates groups consumed 25 gr dark or white chocolate 10 min before each Pilates training session, three times per week, for 8 weeks. The control group consumed 25 gr of the same dark chocolate at a pre-determined time 3 times per week, without any regular exercise. Changes in TAC, BMI and FBG were then measured.

RESULTS

Paired t-test analysis showed significant increases in the TAC status, as compared to the baseline in all groups (P ≤ 0.05). However, BMI and FBG reduction were not significant. Covariance (ANCOVA) analysis also showed a significant difference between groups (p < 0.05). Post-hoc Bonferroni test revealed the group that consumed dark chocolate before training had statistically significant increase in the TAC status compared to other groups.

CONCLUSION

The findings indicated that regular flavanol-rich dark chocolate consumption and Pilates significantly increased the TAC status. While FBG was reduced, it was not statistically significant.

Low doses of cocoa extract supplementation ameliorate diet-induced obesity and insulin resistance in rats

Cocoa polyphenols exhibit high antioxidant activity and have been proposed as a potential adjuvant for the treatment of metabolic disturbances. Here, we demonstrate that supplementation with low doses (14 and 140 mg per kg per rat) of a complete cocoa extract induces metabolic benefits in a diet-induced obesity (DIO) model of Wistar rats. After 10 weeks, cocoa extract-supplemented animals exhibited significantly lower body weight gain and food efficiency, with no differences in energy intake. Cocoa significantly reduced visceral (epididymal and retroperitoneal) and subcutaneous fat accumulation accompanied by a significant reduction in the adipocyte size, which was mediated by downregulation of the adipocyte-specific genes Cebpa, Fasn and Adipoq. Additionally, cocoa extract supplementation reduced the triacylglycerol/high density lipoprotein (TAG/HDL) ratio, decreased hepatic triglyceride accumulation, improved insulin sensitivity by reducing HOMA-IR, and significantly ameliorated glucose tolerance after an intraperitoneal glucose tolerance test. Finally, no adverse effect was observed in an in vivo toxicity evaluation of our cocoa extract at doses up to 500 mg kg^-1 day^-1. Our data demonstrate that low doses of cocoa extract supplementation (14 and 140 mg kg^-1 day^-1) are safe and sufficient to counteract obesity and type-2 diabetes in rats and provide new insights into the potential application of cocoa supplements in the management of the metabolic syndrome.

Ingestion of Lycosome L-tug Formulation of Dark Chocolate Ameliorates Postprandial Hyperlipidemia and Hyperglycemia in Healthy Volunteers

Twenty-eight healthy middle-aged volunteers (40-60 years old) with equal gender representation were randomized into 3 study groups to investigate the changes in postprandial glucose and lipids after ingestion of different formulations of dark chocolate (DC). The volunteers from the first group were requested to ingest 100 g of regular DC whereas the individuals from the third group were given 100 g of highly bioavailable lycosome formulated L-tug formulation of DC containing 23.3 mg of lycopene. A second group received a 23.3 mg lycopene capsule, a tomato-derived antioxidant carotenoid as a matching control. Serum specimens were obtained following 30 minutes as well as 1, 2, and 3 hours after study products intake. Ingestion of L-tug DC was accompanied by the reduced postprandial hyperglycemia with maximum difference seen at 3^rd hour of the study and reduction of average AUC_Gluc values by 20% (P<0.05) as compared to regular DC. Moreover, ingestion of L-tug DC was accompanied by a statistically significantly reduced median concentration for postprandial triglycerides (to 390.7 mg⁎hr/dL; 5/95%% CIs: 363.2/405.7 versus regular DC value of 439.5mg⁎hr/dL and a lower range of confidence intervals - 5/95%CIs: 394.0/475.1). A similar tendency was observed in changes of total cholesterol concentration. Ingestion of L-tug DC completely abolished total cholesterol increase seen in volunteers at 3^rd hour of postprandial period following intake of the control DC. Ingestion of lycopene alone did not cause any changes in postprandial changes of glucose or serum lipids. The observed postprandial changes can be related to the 56.2 % increase in serum lycopene level which was observed after ingestion of L-tug DC only. Higher serum lycopene levels following the ingestion of L-tug DC resulted in a corresponding increase in serum antioxidant capacity and reduction of oxidized LDL as well as a decline in malonic dialdehyde concentration in the serum of volunteers.

Cocoa Flavanols: Natural Agents with Attenuating Effects on Metabolic Syndrome Risk Factors

The interest in cacao flavanols is still growing, as bioactive compounds with potential benefits in the prevention of chronic diseases associated with inflammation, oxidative stress and metabolic disorders. Several analytical methodologies support that the flavanols in cacao-derived products can be absorbed, have bioactive properties, and thus can be responsible for their beneficial effects on human health. However, it must be considered that their biological actions and underlying molecular mechanisms will depend on the concentrations achieved in their target tissues. Based on the antioxidant properties of cacao flavanols, this review focuses on recent advances in research regarding their potential to improve metabolic syndrome risk factors. Additionally, it has included other secondary plant metabolites that have been investigated for their protective effects against metabolic syndrome. Studies using laboratory animals or human subjects represent strong available evidence for biological effects of cacao flavanols. Nevertheless, in vitro studies are also included to provide an overview of these phytochemical mechanisms of action. Further studies are needed to determine if the main cacao flavanols or their metabolites are responsible for the observed health benefits and which are their precise molecular mechanisms.

Right ventricular dysplasia: management and treatment in light of current evidence

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare cardiovascular disease that predisposes to ventricular arrhythmias potentially leading to sudden cardiac death (SCD). ARVC varies considerably with multiple clinical presentations, ranging from no symptoms to cardiac arrhythmias to SCD. ARVC prevalence is not well known, but the estimated prevalence in the general population is 1:5000. Diagnosis of ARVC can be made by using the Revised European Society of Cardiology criteria for ARVC that includes ventricular structural and functional changes, ECG abnormalities, arrhythmias, family and genetic factors. The management of ARVC is focused on prevention of lethal events such as SCD. Implantable cardioverter defibrillator placement is the only proven mortality benefit in treatment of ARVC. Other treatment strategies include medications such as beta blockers and antiarrhythmics, radiofrequency ablation, surgery, cardiac transplantation, and lifestyle changes. All these interventions help in symptomatic treatment but none of them have proved to decrease mortality rates. ARVC is a progressive disease that leads to SCD if not treated appropriately. Management of these diseases has been a challenge for physicians. With the advent of technology and many new drugs/devices under clinical investigation, this might change in the future. However, while advances in technologies have helped elucidate many aspects of these diseases, many mysteries still remain of this unique disease. With continued research, we can expect more cost-effective and patient-friendly drug therapies and ablation techniques to be developed in the near future.