The beneficial effect of intravenous zoledronic acid therapy following an acute stroke in rats

The impact of menopause on bone, zoledronic acid, and implications for breast cancer growth and metastasis

Recent data from the AZURE, ABCSG-12, and ZO-FAST clinical trials have challenged our understanding of the potential anticancer activity of zoledronic acid (ZOL). Although the results of these studies may appear to be conflicting on the surface, a deeper look into commonalities among the patient populations suggest that some host factors (i.e. patient age and endocrine status) may contribute to the anticancer activity of ZOL. Indeed, data from these large clinical trials suggest that the potential anticancer activity of ZOL may be most robust in a low-estrogen environment. However, this may be only part of the story and many questions remain to be answered to fully explain the phenomenon. Does estrogen override the anticancer activity of ZOL seen in postmenopausal women? Are hormones other than estrogen involved that contribute to this effect? Does the role of bone turnover in breast cancer (BC) growth and progression differ in the presence of various estrogen levels? Here, we present a review of the multitude of factors affected by different endocrine environments in women with BC that may influence the potential anticancer activity of ZOL.

Does exercise modify the effects of zoledronic acid on bone mass, microarchitecture, biomechanics, and turnover in ovariectomized rats?

Regular activity has effects on bone size, shape, and density, resulting in an increase in mechanical strength. The mechanism of action that underlies this improvement in bone strength is mainly linked to an increase in bone formation. Zoledronic acid (Z), in contrast, may prevent bone strength changes in ovariectomized (OVX) rodents by its potent antiresorptive effects. Based on these assumptions we hypothesized that combined effects of exercise (E) and Z may produce higher benefits on bone changes resulting from estrogen deficiency than either intervention alone. At 6 months of age, 60 female Wistar rats were OVX or sham operated (SH) and divided into five groups: SH, OVX, OVX-E, OVX-Z, and OVX-ZE. OVX rats were treated with a single IV injection of Z (20 microg/kg) or vehicle and submitted or not to treadmill exercise (15 m/min, 60 min/day, 5 days/week) for 12 weeks. Whole-body BMD and bone turnover markers were analyzed longitudinally. At sacrifice, femurs were removed. BMD by DXA, three-point bending test, and microCT were performed to study biomechanical and trabecular structure parameters, respectively. After 12 weeks, bone volume fraction decreased in OVX rats, whereas bone turnover rate, trabecular spacing, and structure model index increased compared with those in the SH group (P < 0.05). Zoledronic acid prevented the ovariectomy-induced trabecular bone loss and its subsequent trabecular microarchitectural deterioration. Treadmill exercise running was shown to preserve the bone strength and to induce bone turnover changes in favor of bone formation. However, the combined effects of zoledronic acid and running exercise applied simultaneously did not produce any synergetic or additive effects.

Bone health in stroke

In 2004 the Stroke Association stated ‘Each year over 130,000 people in England and Wales have a stroke. Of all people who suffer from a stroke, about a third are likely to die within the first 10 days, about a third are likely to make a recovery within one month and about a third are likely to be left disabled and needing rehabilitation. Stroke has a greater disability impact than any other medical condition. A quarter of a million people are living with long-term disability as a result of stroke in the UK.’