Multiple factors contribute to these metabolic derangements, including adipose tissue dysfunction, increased hepatic lipogenesis, reduced skeletal muscle mitochondrial content, and microbiota dysbiosis.
Two countries, the US and Mexico, grapple with alarmingly high obesity rates, signifying an urgent need for investigating the mechanisms underlying the transition from obesity to metabolic syndrome.
This article delves into the potential of pecan nuts, particularly their phenolic compounds, as a dietary intervention strategy against metabolic syndrome.
Obesity Epidemic and its Consequences
The financial burden of obesity is staggering; in Mexico, projected healthcare costs may rise to around USD 1.7 billion by 2050. In the US, obesity contributes to a yearly expenditure of approximately USD 147 billion, amounting to 9% of annual medical costs. Even a marginal reduction in obesity rates could translate to substantial cost savings.
Obesity and Metabolic Syndrome: A Looming Crisis
Cardiovascular disease and type 2 diabetes are leading causes of mortality in both countries, necessitating a deeper exploration of the link between obesity and metabolic syndrome. Metabolic syndrome, characterized by multiple health abnormalities, demands focused research efforts to develop novel preventive and therapeutic approaches. Among these, the integration of functional foods, rich in bioactive compounds, holds promise in combating metabolic syndrome. Functional foods, including fruits, vegetables, grains, and nuts, are being investigated for their potential health-promoting effects.
Dietary Patterns and Obesity
Pecan Nuts: An Overlooked Treasure
Pecan nuts, originating from the US and Mexico, have garnered attention due to their unique chemical composition. Rich in condensed and hydrolysable tannins, polyunsaturated fatty acids, and antioxidants, pecans offer potential health benefits. Clinical studies have shown reductions in LDL oxidation, LDL cholesterol, and improvements in cardiometabolic risk factors upon pecan consumption. However, these studies were conducted within a limited dose range, possibly underestimating the full potential of pecan phenolic compounds.
Unlocking the Potential: The Study Framework
To comprehensively investigate the impact of pecans and their phenolic extracts on the progression of metabolic disorders during diet-induced obesity, researchers have established a detailed framework. This framework categorizes the metabolic alterations into early and late events, enabling the assessment of biochemical, histological, and molecular effects. Employing both preventive and intervention strategies, researchers aim to unravel the preventive and mitigative properties of pecans against metabolic syndrome.
Discussion
Functional Role of Pecans as Nutraceutical-Rich Foods
Pecans, renowned for their abundance of nutraceuticals including unsaturated fatty acids, dietary fiber, and polyphenols, have earned their status as functional foods. A mounting body of basic and clinical studies has illuminated the advantages of nutraceutical-rich diets in thwarting obesity and metabolic syndrome.
This study centers on investigating the preventive and interventional potential of pecans, specifically their phenolic compounds, in mitigating the cascade of metabolic disturbances that accompany high-fat diet-induced obesity.
Early and Late Events in Metabolic Dysfunction
Metabolic disturbances triggered by high-fat diets operate in a complex network of interrelated events that culminate in chronic diseases. However, these derangements don’t manifest concurrently; rather, they evolve in a sequential manner.
The metabolic cascade leading to conditions like non-alcoholic fatty liver disease (NAFLD), type 2 diabetes, and cardiovascular diseases can be subdivided into early and late events concerning the timing of organ-specific alterations.
A comprehensive model, as depicted in Figure 11A, outlines these metabolic alterations’ early and late responses. The early events involve the reduction in colonic microbial diversity, consequent dysbiosis, and heightened release of inflammatory endotoxins such as lipopolysaccharide (LPS). Concurrently, excess energy is stored in adipose tissues, a process regulated by the PPAR gamma pathway, which also influences adipose tissue expansion, fat oxidation, and thermogenesis.
Prolonged overnutrition hampers PPAR gamma activity, instigating adipocyte hypertrophy and dysfunction. This disrupted adipose tissue environment, characterized by escalated macrophage infiltration, compromised adiponectin secretion, and elevated lipolysis, perpetuates inflammation.
The ensuing pro-inflammatory and lipotoxic milieu sets the stage for later changes in peripheral organs, such as the liver, skeletal muscle, brown adipose tissue, and pancreas. This low-grade inflammation transforms into a chronic state, prompting the subsequent late events.
Molecular Mechanisms and Targets of Pecan Phenolics
Whole pecans and pecan phenolic extracts demonstrated remarkable efficacy in averting obesity, liver steatosis, and diabetes. These effects stem from the modulation of several molecular targets across various metabolic organs. Pecan bioactives exert dual actions: direct effects on specific molecular pathways and indirect effects triggered by the direct actions.
These actions intertwine to produce the observed beneficial outcomes. The targets include promoting prebiotic effects, up-regulating PPAR gamma and UCP-1 in adipose tissues, enhancing p-AMPK and p-AKT levels in skeletal muscle, and increasing p-AMPK and p-AKT in liver tissue. Together, these actions mitigate inflammation, lipid accumulation, insulin resistance, and oxidative stress. The resulting reduction in oxidative stress and inflammation, coupled with improved insulin sensitivity and lipid metabolism, collaboratively contributes to the prevention of obesity and its associated metabolic sequelae.
Toward Clinical Implications: Dose and Translatability
The transition from murine studies to clinical applications necessitates a rational approach to dosage conversion. In this study, the phenolic content of pecans was standardized across different interventions. By extrapolating the dose administered in mice to a human equivalent, a daily consumption range for humans was suggested. The proposed range of 110.1–183.5 g of pecan kernels, or 34.2–36 g of defatted pecan flour, would supply 88.4–147.4 g of healthy fats—akin to the Mediterranean diet’s recommended fat intake. These findings underscore the potential to harness the benefits of pecans by integrating them into dietary habits.
Limitations and Future Directions
While murine models offer insights into potential human responses, differences between species necessitate cautious extrapolation of findings. Additionally, the presence of allergens in pecans poses potential concerns, necessitating allergen monitoring and the exploration of low-allergenic pecan varieties. Moreover, the study’s timeframe may have limited the full realization of pecan polyphenols’ interventional effects. Extended interventions targeting the core inflammatory and lipotoxic milieu could potentially unveil stronger therapeutic outcomes.
Conclusion
The exploration of pecans and their phenolic compounds as a defense against high-fat diet-induced metabolic disruptions opens a promising avenue for preventive and therapeutic interventions. By targeting a network of molecular pathways, pecan phenolics exhibit potential in averting obesity, diabetes, and related complications. As the world grapples with rising obesity rates and metabolic syndrome, the efficacy of pecans in curbing these epidemics invites further research and holds significant promise for improving global health outcomes.
reference link: https://www.mdpi.com/2072-6643/15/11/2591