Olive (Olea europaea L.) leaf polyphenols improve insulin sensitivity in middle-aged overweight men: a randomized, placebo-controlled, crossover trial.
PLoS One
; 8(3): e57622, 2013.
Article
en En
| MEDLINE
| ID: mdl-23516412
ABSTRACT
BACKGROUND:
Olive plant leaves (Olea europaea L.) have been used for centuries in folk medicine to treat diabetes, but there are very limited data examining the effects of olive polyphenols on glucose homeostasis in humans.OBJECTIVE:
To assess the effects of supplementation with olive leaf polyphenols (51.1 mg oleuropein, 9.7 mg hydroxytyrosol per day) on insulin action and cardiovascular risk factors in middle-aged overweight men.DESIGN:
Randomized, double-blinded, placebo-controlled, crossover trial in New Zealand. 46 participants (aged 46.4 ± 5.5 years and BMI 28.0 ± 2.0 kg/m(2)) were randomized to receive capsules with olive leaf extract (OLE) or placebo for 12 weeks, crossing over to other treatment after a 6-week washout. Primary outcome was insulin sensitivity (Matsuda method). Secondary outcomes included glucose and insulin profiles, cytokines, lipid profile, body composition, 24-hour ambulatory blood pressure, and carotid intima-media thickness.RESULTS:
Treatment evaluations were based on the intention-to-treat principle. All participants took >96% of prescribed capsules. OLE supplementation was associated with a 15% improvement in insulin sensitivity (p = 0.024) compared to placebo. There was also a 28% improvement in pancreatic ß-cell responsiveness (p = 0.013). OLE supplementation also led to increased fasting interleukin-6 (p = 0.014), IGFBP-1 (p = 0.024), and IGFBP-2 (p = 0.015) concentrations. There were however, no effects on interleukin-8, TNF-α, ultra-sensitive CRP, lipid profile, ambulatory blood pressure, body composition, carotid intima-media thickness, or liver function.CONCLUSIONS:
Supplementation with olive leaf polyphenols for 12 weeks significantly improved insulin sensitivity and pancreatic ß-cell secretory capacity in overweight middle-aged men at risk of developing the metabolic syndrome.
Texto completo:
1
Bases de datos:
MEDLINE
Métodos Terapéuticos y Terapias MTCI:
Terapias_biologicas
/
Plantas_medicinales
Asunto principal:
Resistencia a la Insulina
/
Hojas de la Planta
/
Olea
/
Sobrepeso
/
Polifenoles
Tipo de estudio:
Clinical_trials
/
Diagnostic_studies
/
Risk_factors_studies
País/Región como asunto:
Oceania
Idioma:
En
Revista:
PLoS One
Año:
2013
Tipo del documento:
Article
País de afiliación:
Nueva Zelanda