Enhancing the Bioavailability and Bioactivity of Curcumin for Disease Prevention and Treatment.

Curcumin, a natural polyphenolic component from Curcuma longa roots, is the main bioactive component of turmeric spice and has gained increasing interest due to its proposed anti-cancer, anti-obesity, anti-inflammatory, antioxidant, and lipid-lowering effects, in addition to its thermogenic capacity. While intake from dietary sources such as curry may be sufficient to affect the intestinal microbiome and thus may act indirectly, intact curcumin in the body may be too low (<1 microM) and not sufficient to affect signaling and gene expression, as observed in vitro with cultured cells (10-20 microM). Several strategies can be envisioned to increase curcumin levels in the body, such as decreasing its metabolism or increasing absorption through the formation of nanoparticles. However, since high curcumin levels could also lead to undesired regulatory effects on cellular signaling and gene expression, such studies may need to be carefully monitored. Here, we review the bioavailability of curcumin and to what extent increasing curcumin levels using nanoformulations may increase the bioavailability and bioactivity of curcumin and its metabolites. This enhancement could potentially amplify the disease-preventing effects of curcumin, often by leveraging its robust antioxidant properties.

Bioactive dietary components-Anti-obesity effects related to energy metabolism and inflammation.

Obesity is the result of the long-term energy imbalance between the excess calories consumed and the few calories expended. Reducing the intake of energy dense foods (fats, sugars), and strategies such as fasting and caloric restriction can promote body weight loss. Not only energy in terms of calories, but also the specific composition of the diet can affect the way the food is absorbed and how its energy is stored, used or dissipated. Recent research has shown that bioactive components of food, such as polyphenols and vitamins, can influence obesity and its pathologic complications such as insulin resistance, inflammation and metabolic syndrome. Individual micronutrients can influence lipid turnover but for long-term effects on weight stability, dietary patterns containing several micronutrients may be required. At the molecular level, these molecules modulate signaling and the expression of genes that are involved in the regulation of energy intake, lipid metabolism, adipogenesis into white, beige and brown adipose tissue, thermogenesis, lipotoxicity, adipo/cytokine synthesis, and inflammation. Higher concentrations of these molecules can be reached in the intestine, where they can modulate the composition and action of the microbiome. In this review, the molecular mechanisms by which bioactive compounds and vitamins modulate energy metabolism, inflammation and obesity are discussed.

The Dose-Dependent Effect of Curcumin Supplementation on Inflammatory Response and Gut Microbiota Profile in High-Fat Fed C57BL/6 Mice.

SCOPE: The prevalence of obesity has increased, with excessive consumption of high-fat foods being one of the primary causes. Curcumin, a polyphenol extracted from Curcuma longa L., exhibits anti-inflammatory activity.  The study aims to investigate the effects of curcumin supplementation in different doses on the biochemical profile, inflammatory response, and gut microbiota profile in mice that are fed with high-fat diet (HFD). METHODS AND RESULTS: C57BL/6 male mice are fed a standard diet, or a HFD with or without different doses of curcumin (50, 250, and 500 mg kg-1 of body weight). Throughout the experimental period, food intake and body weight are assessed weekly. At euthanasia, blood, stool, and tissue samples are collected for biochemical, histological, and molecular analyses. Curcumin increases the IL-10 protein expression in the white adipose tissue. In the liver, there is a reduction in tumor necrosis factor alpha (TNF-α) and an increase in IL-10 gene expression. Also, curcumin promotes the growth of butyrogenic bacteria, such as Clostridium clusters IV and XIVa. CONCLUSIONS: The findings suggest that curcumin has the potential to improve the inflammatory response and modulate healthy gut microbiota. Further studies are needed to clarify the role of curcumin as a preventive and effective strategy for obesity.

Effect of bariatric surgery on neurocognitive function after 6 months of follow-up: a pilot study.

Introduction: Background: reduced cognitive performance has been observed in patients with severe obesity. Bariatric surgery and subsequent adipose tissue loss seem to affect cognitive functioning positively; however, improvement predictors are not well established. Aim: to evaluate the cognitive performance and the nutritional status of patients with severe obesity 6-month after bariatric surgery. Methods: we assessed the neuropsychological performance of 22 patients with obesity (body mass index: ~ 42.9 kg/m²). The nutritional evaluation consisted of the routine tests performed in the baseline and postoperative periods. Lastly, we calculated the correlation between neuropsychological assessment results and blood biomarkers. Results: the patients did not present cognitive impairment in the preoperative assessment, but performed below the standard range. The patients underwent significant weight loss after 6 months from surgery (~ 22 kg), with a change in obesity class III to I. Also, the patients presented a significant improvement in attention, mental flexibility, inhibitory control, and processing speed. Additionally, we observed a significant improvement in serum folic acid (108 %), gamma-glutamyl transferase (-41 %), uric acid (-32 %), ferritin (-28 %), triglycerides (-19 %), and high-density lipoprotein (9 %). Lastly, we found a moderate positive correlation between processing speed and body weight (r = 0.46), gamma-glutamyl transferase (r = 0.54), and total protein and mental flexibility (r = 0.75). Conclusion: bariatric surgery promoted significant weight loss and improved attention, mental flexibility, processing speed, and several nutritional biomarkers. Nevertheless, the surgery had limited effects on other cognitive functions such as short- and long-term memory and language.

Introducción: Introducción: se ha observado una disminución del rendimiento cognitivo en los pacientes con obesidad grave. La cirugía bariátrica y la pérdida de tejido adiposo parecen mejorar el funcionamiento cognitivo; sin embargo, los predictores de mejora no están bien establecidos. Objetivos: evaluar el rendimiento cognitivo y el estado nutricional de pacientes con obesidad severa después de 6 meses de una cirugía bariátrica. Métodos: evaluamos el desempeño neuropsicológico de 22 pacientes con un índice de masa corporal ~ 42,9 kg/m². Se analizaron las pruebas de rutina realizadas al inicio y después de la cirugía. Calculamos la correlación con la evaluación neuropsicológica y los biomarcadores sanguíneos. Resultados: los pacientes no mostraron deterioro cognitivo en la evaluación preoperatoria, pero sí un rendimiento por debajo del estándar. Los pacientes mostraron una pérdida de peso significativa 6 meses después de la cirugía (~ 22 kg), con un cambio de la clasificación de obesidad de III a I. Además, los pacientes mostraron una mejora significativa de la atención, la flexibilidad mental, el control inhibitorio y la velocidad de procesamiento. Además, observamos una mejora significativa del ácido fólico sérico (108 %), la gamma-glutamil-transferasa (-41 %), el ácido úrico (-32 %), la ferritina (-28 %), los triglicéridos (-19 %) y las lipoproteínas de alta densidad (9 %). Finalmente, encontramos una correlación positiva moderada entre la velocidad de procesamiento y el peso corporal (r = 0,46) y la gamma-glutamil-transferasa (r = 0,54), y entre la proteína total y la flexibilidad mental (r = 0,75). Conclusiones: la cirugía bariátrica promovió una pérdida de peso significativa y mejoró la atención, la flexibilidad mental, la velocidad de procesamiento y varios biomarcadores nutricionales. Sin embargo, tuvo efectos limitados sobre otras funciones cognitivas, como la memoria y el lenguaje a corto y largo plazo.

Beneficial effects of eugenol supplementation on gut microbiota and hepatic steatosis in high-fat-fed mice.

Due to the increase in the prevalence of obesity, new therapies have emerged and eugenol has been shown to be beneficial in metabolic changes and gut microbiota. This study aimed to investigate the effects of eugenol on gut microbiota, hepatic lipid accumulation, body weight, adipose tissue weight, lipid and glycemic profile in mice fed a high-fat diet. Forty C57BL/6 male mice were divided into standard diet (SD), high-fat diet (HFD), standard diet with eugenol (SDE) and high-fat diet with eugenol (HFDE). The dose used of eugenol was 500 mg kg-1 for 8 weeks. Eugenol did not prevent weight gain, but it was effective in preventing hepatic lipid accumulation evidenced by the presence of fat droplets in the HFD group and absence in the HFDE group. An improvement in the gut microbiota profile was observed, proved by an increase in the Actinobacteria phylum in the treated groups and a reduction of Proteobacteria phylum in the HFDE group. Despite not preventing weight gain, eugenol appeared to have a protective effect on hepatic lipid accumulation and beneficially modulate the gut microbiota in mice fed with HFD.