کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2779956 1153287 2011 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Differential effects of two citrus flavanones on bone quality in senescent male rats in relation to their bioavailability and metabolism
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شناسی تکاملی
پیش نمایش صفحه اول مقاله
Differential effects of two citrus flavanones on bone quality in senescent male rats in relation to their bioavailability and metabolism
چکیده انگلیسی

The effect of hesperidin (Hp) and naringin (Nar), two major citrus flavanones, on the regulation of bone metabolism was examined in male senescent rats. Twenty -month -old gonad-intact male Wistar rats received a casein-based diet supplemented with or without either 0.5% hesperidin (Hp), 0.5% naringin (Nar) or a mix of both flavanones (Hp + Nar, 0.25% each). After 3 months, daily Hp intake significantly improved femoral bone integrity as reflected by improvements in total and regional bone mineral densities (BMD) (9.7%–12.3% improvements, p < 0.05) and trabecular bone volume fraction (24.3% improvement, p < 0.05) at the femur compared with control group. In contrast, naringin exerted site-specific effects on BMD (10.2% improvement at the distal metaphyseal area, p < 0.05) and no further benefit to bone mass was observed with the mix of flavanones. Bone resorption (DPD) was significantly attenuated by Hp and Nar given alone (40.3% and 26.8% lower compared to control, p < 0.05, respectively) but not by the mixture of the two. All treatments significantly reduced expression of inflammatory markers to a similar extent (IL-6, 81.0–87.9% reduction; NO, 34.7–39.5% reduction) compared to control. Bone formation did not appear to be strongly affected by any of the treatments (no effect on osteocalcin levels, modest modulation of tibial BMP-2 mRNA). However, as previously reported, plasma lipid-lowering effects were observed with Hp and Nar alone (34.1%–45.1% lower for total cholesterol and triglycerides compared to control, p < 0.05) or together (46% lower for triglycerides, p < 0.05). Surprisingly the plasma circulating level of naringin (8.15 μM) was > 5-fold higher than that of hesperidin (1.44 μM) at equivalent doses (0.5%) and a linear reduction in plasma levels was observed upon co-administration (0.25% each) indicating absence of competition for their intestinal absorption sites and metabolism. The higher efficacy of Hp at a lower plasma concentration than naringin, as well as the identification of the major circulating metabolite of hesperidin (hesperetin-7-O-glucuronide) underlines the importance of flavanone bioavailability and metabolism in their biological efficacy and suggests a structure–function relationship in the mechanism of action of the active metabolites.


► Nutritional levels of hesperidin improve femoral bone integrity (BMD and microarchitecture).
► Naringin is less effective and site-specific in improving bone mass despite its higher bioavaiability.
► Flavanone structure–function relationship is implicated in the mechanism of action of the active metabolites.
► Flavanone action is mainly through bone resorption decrease as well as reduced expression of inflammatory markers (Il-6, NO).

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Bone - Volume 49, Issue 5, November 2011, Pages 1108–1116
نویسندگان
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