Cumulative Effects of Strontium Ranelate and Impact Exercise on Bone Mass in Ovariectomized Rats.

Priscilla Aveline,Thomas M Best,Marija Mazor,Eric Lespessailles,Annabelle Cesaro,Hechmi Toumi

doi:10.3390/ijms22063040

Abstract

OBJECTIVE: To explore the effect of physical exercise (EXE), strontium ranelate (SR), or their combination on bone status in ovariectomized (OVX) rats. DESIGN: Sixty female Wistar rats were randomized to one of five groups: sham (Sh), OVX (O), OVX+EXE (OE), OVX+SR (OSR), and OVX+EXE+SR (OESR). Animals in EXE groups were subjected to 10 drops per day (45 cm in height); rats in SR groups received 625 mg/kg/day of SR, 5 days/week for 8 weeks. Bone mineral density (BMD) and bone mineral content (BMC, dual-energy X-ray absorptiometry (DXA)), mechanical strength of the left femur (three-point bending test), and femur microarchitecture of (micro-computed tomography imaging, microCT) analyses were performed to characterize biomechanical and trabecular/cortical structure. Bone remodeling, osteocyte apoptosis, and lipid content were evaluated by ELISA and immunofluorescence tests. RESULTS: In OVX rats, whole-body BMD, trabecular parameters, and osteocalcin (OCN) levels decreased, while weight, lean/fat mass, osteocyte apoptosis, and lipid content all increased. EXE after ovariectomy improved BMD and BMC, trabecular parameters, cross-sectional area (CSA), moment of inertia, and OCN levels while decreasing osteocyte apoptosis and lipid content. SR treatment increased BMD and BMC, trabecular parameters, CSA, stiffness, OCN, and alkaline phosphatase (ALP) levels. Furthermore, fat mass, N-telopeptide (NTX) level, osteocyte apoptosis, and lipid content significantly decreased. The combination of both EXE and SR improved bone parameters compared with EXE or SR alone. CONCLUSION: EXE and SR had positive and synergistic effects on bone formation and resorption.

Highlights

IntroductionTreatment strategies in osteoporosis are based on both pharmacological [1] and nonpharmacological approaches to treatment, including fall prevention, calcium and vitamin
Treatment strategies in osteoporosis are based on both pharmacological [1] and nonpharmacological approaches to treatment, including fall prevention, calcium and vitaminD supplementation, exclusion of tobacco, and physical exercise (EXE) [2,3].Pharmacologic treatments for osteoporosis generally target either bone formation or bone resorption [4,5]
Our results showed that both strontium ranelate (SR) and impact exercise had beneficial effects on bone tissue in enhancing bone microarchitecture and strength

Summary

Introduction

Treatment strategies in osteoporosis are based on both pharmacological [1] and nonpharmacological approaches to treatment, including fall prevention, calcium and vitamin. Pharmacologic treatments for osteoporosis generally target either bone formation or bone resorption [4,5]. One agent, strontium ranelate (SR), acts on both bone formation and resorption [6,7,8,9]. Previous studies have shown that SR administration significantly reduced the risk of vertebral, non-vertebral, and hip fractures in postmenopausal women [4]. SR administration reduces bone resorption and stimulates bone formation [10]. By increasing osteoblast differentiation, decreasing osteoclast differentiation, and increasing synthesis of collagen and non-collagen proteins [10,11,12].

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Results

Conclusion