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The aim of this research was to evaluate the fracture healing area in osteoporotic femur of female rats restrained by stainless steel wire by statin administration in two different doses (5 mg and 20 mg). Ninety female rats were divided into six groups (n = 15): SH, SH-5 mg, SH-20 mg, OVX, OVX-5 mg, and OVX-20 mg. The surgery consisted of the fracture of the left femur bone and stabilization by K-wire and the administration was restricted and weekly controlled in the drinking water. The euthanasia was conducted at three different moments, five animals per period: 7 d, 14 d, and 28 d. Densitometry, zymography, and histological analyses showed a significant difference between some groups. According to these findings, simvastatin promoted a positive action for bone repair, especially in the osteometabolic group treated with 20 mg of the drug.

Proteins with osteoinductive potential, especially recombinant human bone morphogenetic protein (rhBMP)‐2, have large effects on cell growth and their differentiation. The aim of this study was to assess repair of bone defects in rat calvaria with different types of grafts associated with rhBMP‐2, through immunohistochemistry and micro computed tomography (CT) analyses. A total of 35 male Wistar rats were selected, each weighing ~250 g, with a waiting period of 6 weeks from the creation of the defect to the sacrifice, and divided into five groups (n = 7): autograft plus 5 μg rhBMP‐2 (AuG/BMP‐2); allograft plus 5 μg rhBMP‐2 (AlG/BMP‐2); xenograft (heterologous) plus 5 μg rhBMP‐2 (XeG/BMP‐2); 5 μg rhBMP‐2 (BMP‐2) and the control group (n = 7). The micro CT reveal that all groups associating different bone grafts with BMP‐2 showed increased bone formation compared to the control. The immunostaining show that osteocalcin and bone sialoprotein were higher in groups with BMP‐2 than control group; BMP was high expressed in AuG/BMP‐2, AlG/BMP‐2, and BMP‐2; vascular endothelial growth factor (VEGF) was more expressed in groups with BMP‐2; VEGF‐R2 was low to moderate in AuG/BMP‐2, XeG/BMP‐2, and BMP‐2, predominantly moderate in AlG/BMP‐2 and low in the control; CD‐31 was predominantly moderate in AuG/BMP‐2, AlG/BMP‐2, and XeG/BMP‐2, low to moderate in BMP‐2 and low in the control. The results revealed that rhBMP‐2 improved bone repair when administered alone, or when associated with different bone grafts.

The objective of this study was to evaluate the microarchitecture and trabecular bone strength at the distal region of the femur, and its biomechanical properties with simvastatin administration with two different doses in ovariectomized (OVX) rats. Ninety rats were divided into six groups to evaluate treatment with the simvastatin drug (n = 15): SH (Sham surgery), SH-5 (5 mg simvastatin), SH-20 (20 mg simvastatin), OVX, OVX-5, and OVX-20. Euthanasia was performed at three different times, five animals per period: 7, 14, and 28 days. The effectiveness of the treatments was evaluated by mechanical testing and histomorphometric analysis of the femurs. The results of analysis by the linear model of mixed effects showed 20 mg of simvastatin results in increased trabecular bone after 14 days (P = 0.039) of ingestion in ovariectomized animals. However, ingestion of 5 mg of simvastatin is able to sensitize the trabecular bone only at 28 days (P = 0.005) of ingestion. In the mechanical tests stiffness improves within 28 days (P = 0.003). Regarding maximum strength, no statistical differences were observed. According to these results, it can be concluded that for a decrease in oral intake, longer treatment times are required. Microsc. Res. Tech. 79:684-690, 2016. © 2016 Wiley Periodicals, Inc.

Osteoporosis and cardiovascular diseases are common causes of morbidity and mortality worldwide, especially in people aged over 60 years. Osteoporosis is characterized by low bone mineral density, which deteriorates the microarchitecture of bones and increases the risk of bone fractures. Other pathologies also constitute risk factors for the development of osteoporosis, mainly cardiovascular diseases. In fact, a growing number of reports have shown a positive correlation between cardiovascular diseases and low bone mineral density. MMPs are proteases that participate in the organized degradation of the extracellular matrix (ECM) and which play essential physiological roles, such as cardiovascular and bone tissue remodeling. Overexpression of MMPs underlies pathological processes like osteoporosis and cardiovascular diseases. MMP-1, -2, -9, -13, and -14 are expressed in bone tissue and are key players in the digestion of bone matrix by osteoblasts. Considering this relationship between osteometabolic and cardiovascular pathologies and MMPs, this review focuses on the involvement of MMPs in osteoporosis and on their participation in cardiovascular diseases; it also deals with the positive correlation between osteoporosis and cardiovascular diseases. Although there are many drugs to treat osteoporosis, controversies exist. Here, we will describe these controversies and will discuss how inhibition of MMPs could be an alternative strategy to or an adjuvant therapy in the current treatment of osteoporosis.