RESUMEN
Despite being largely preventable, cardiovascular disease (CVD) is still the leading cause of death globally. Recent studies suggest that the immune system, particularly a form of systemic chronic inflammation (SCI), is involved in the mechanisms leading to CVD; thus, targeting SCI may help prevent or delay the onset of CVD. In a recent placebo-controlled randomized clinical trial, an oat product providing 3 g of ß-Glucan improved cholesterol low-density lipoprotein (LDL) levels and lowered cardiovascular risk in adults with borderline high cholesterol. Here, we conducted a secondary measurement of the serum samples to test whether the oat product has the potential to reduce SCI and improve other clinical outcomes related to healthy aging. We investigated the effects of the oat product on a novel metric for SCI called Inflammatory Age® (iAge®), derived from the Stanford 1000 Immunomes Project. The iAge® predicts multimorbidity, frailty, immune decline, premature cardiovascular aging, and all-cause mortality on a personalized level. A beneficial effect of the oat product was observed in subjects with elevated levels of iAge® at baseline (>49.6 iAge® years) as early as two weeks post-treatment. The rice control group did not show any significant change in iAge®. Interestingly, the effects of the oat product on iAge® were largely driven by a decrease in the Eotaxin-1 protein, an aging-related chemokine, independent of a person's gender, body mass index, or chronological age. Thus, we describe a novel anti-SCI role for oats that could have a major impact on functional, preventative, and personalized medicine.
Asunto(s)
Avena , Enfermedades Cardiovasculares , Adulto , Humanos , LDL-Colesterol , Enfermedades Cardiovasculares/etiología , Fibras de la Dieta/análisis , Colesterol , Grano Comestible/química , Inflamación/tratamiento farmacológicoRESUMEN
Pancreatic ß-cell dysfunction and death contribute to the onset of diabetes, and novel strategies of ß-cell function and survival under diabetogenic conditions need to be explored. We previously demonstrated that Isx9, a small molecule based on the isoxazole scaffold, drives neuroendocrine phenotypes by increasing the expression of genes required for ß-cell function and improves glycemia in a model of ß cell regeneration. We further investigated the role of Isx9 in ß-cell survival. We find that Isx9 drives the expression of Calbindin-D28K (D28K), a key regulator of calcium homeostasis, and plays a cytoprotective role through its calcium buffering capacity in ß cells. Isx9 increased the activity of the calcineurin (CN)/cytoplasmic nuclear factor of the activated T-cells (NFAT) transcription factor, a key regulator of D28K, and improved the recruitment of NFATc1, cAMP response element-binding protein (CREB), and p300 to the D28K promoter. We found that nutrient stimulation increased D28K plasma membrane enrichment and modulated calcium channel activity in order to regulate glucose-induced insulin secretion. Isx9-mediated expression of D28K protected ß cells against chronic stress induced by serum withdrawal or chronic inflammation by reducing caspase 3 activity. Consequently, Isx9 improved human islet function after transplantation in NOD-SCID mice in a streptozotocin-induced diabetes model. In summary, Isx9 significantly regulates expression of genes relevant to ß cell survival and function, and may be an attractive therapy to treat diabetes and improve islet function post-transplantation.
Asunto(s)
Calbindinas/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Secretoras de Insulina/efectos de los fármacos , Isoxazoles/farmacología , Tiofenos/farmacología , Animales , Calbindinas/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Diabetes Mellitus Experimental/metabolismo , Humanos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patología , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/metabolismo , Trasplante de Islotes Pancreáticos , Ratones Endogámicos NOD , Ratones SCID , Factores de Transcripción NFATC/genética , Factores de Transcripción NFATC/metabolismo , RatasRESUMEN
Diabetes prevalence increases with age, and ß-cell dysfunction contributes to the incidence of the disease. Dietary lipids have been recognized as contributory factors in the development and progression of the disease. Unlike long chain triglycerides, medium chain triglycerides (MCT) increase fat burning in animal and human subjects as well as serum C-peptide in type 2 diabetes patients. We evaluated the beneficial effects of MCT on ß-cells in vivo and in vitro. MCT improved glycemia in aged rats via ß-cell function assessed by measuring insulin secretion and content. In ß-cells, medium chain fatty acid (MCFA)-C10 activated fatty acid receptor 1 FFAR1/GPR40, while MCFA-C8 induced mitochondrial ketogenesis and the C8:C10 mixture improved ß cell function. We showed that GPR40 signaling positively impacts ketone body production in ß-cells, and chronic treatment with ß-hydroxybutyrate (BHB) improves ß-cell function. We also showed that BHB and MCFA help ß-cells recover from lipotoxic stress by improving mitochondrial function and increasing the expression of genes involved in ß-cell function and insulin biogenesis, such as Glut2, MafA, and NeuroD1 in primary human islets. MCFA offers a therapeutic advantage in the preservation of ß-cell function as part of a preventative strategy against diabetes in at risk populations.