The effect of gabapentin and pregabalin on bone turnover and bone strength: A prospective study in Wistar rats

The impact of antiseizure medication on bone heath: A systematic review of animal studies

BACKGROUND

Antiseizure medications (ASMs) are known to potentially impact bone health, but existing literature presents conflicting results regarding their specific effects on bone mineralization, metabolism, and quality.

OBJECTIVE

This systematic review aims to establish a consensus regarding the influence of ASMs on bone health based on existing preclinical studies.

METHODS

Following SYRCLE and PRISMA guidelines, we conducted a systematic search in PubMed, Science Direct, and Google Scholar to identify relevant studies. Ultimately, 21 articles were selected for inclusion in this review.

RESULTS

Among the chosen studies, approximately half involved Wistar rats as experimental subjects. Levetiracetam and sodium valproate were the most frequently investigated drugs, with a typical treatment duration of 10-12 weeks. These studies exhibited a low risk of bias in aspects like sequence generation, random housing, random outcome assessment, and reporting bias. However, blinding in performance, allocation concealment, and detection were often rated as having a high risk of bias. The collective findings suggest that prolonged ASM use leads to reduced bone mineral density, altered bone turnover marker levels (including hypovitaminosis D, hypocalcemia, and secondary hyperparathyroidism), deterioration of bone microarchitecture, and decreased mechanical strength.

CONCLUSION

The adverse effects on bone associated with ASMs are not limited to enzyme-inducing drugs, as newer generation ASMs may also contribute to these effects. Hypovitaminosis D alone may not be solely responsible for ASM-induced bone issues, suggesting the involvement of other mechanisms. Furthermore, substantial variations were observed in the results of different preclinical studies on individual ASMs, highlighting the need to standardize animal study methodologies to enhance reproducibility and reduce variation.

Effects of Gabapentin and Pregabalin on Calcium Homeostasis: Implications for Physical Rehabilitation of Musculoskeletal Tissues

PURPOSE OF REVIEW

In this review, we discuss the mechanism of action of gabapentinoids and the potential consequences of long-term treatment with these drugs on the musculoskeletal system.

RECENT FINDINGS

Gabapentinoids, such as gabapentin (GBP) and pregabalin (PGB) were designed as antiepileptic reagents and are now commonly used as first-line treatment for neuropathic pain and increasingly prescribed off-label for other pain disorders such as migraines and back pain. GBP and PGB exert their analgesic actions by selectively binding the α₂δ₁ auxiliary subunit of voltage-sensitive calcium channels, thereby inhibiting channel function. Numerous tissues express the α₂δ₁ subunit where GBP and PGB can alter calcium-mediated signaling events. In tissues such as bone, muscle, and cartilage, α₂δ₁ has important roles in skeletal formation, mechanosensation, and normal tissue function/repair that may be affected by chronic use of gabapentinoids. Long-term use of gabapentinoids is associated with detrimental musculoskeletal outcomes, including increased fracture risk. Therefore, understanding potential complications is essential for clinicians to guide appropriate treatments.

The Effect of Pregabalin on Bone Metabolism

The aim of the study was to determine the effect of pregabalin as monotherapy on biochemical markers and bone mineral density. 40 patients diagnosed with neuropathic pain or fibromyalgia syndrome who were using pregabalin for at least 6 months and age and sex matched 40 healthy individuals were recruited for this cross-sectional study. Bone mineral density of both groups were measured by dual energy x ray absorbsiometry(DXA), bone biochemical markers, serum calcium, and vitamin D levels were investigated. Association between pregabalin use and bone biochemical markers, serum calcium, vitamin D levels were evaluated. The mean age of 40 patients (27 females, 13 males) was 40.6 ± 7.1 years and the mean age of 40 healthy individuals (27 females, 13 males) was 40.4 ± 7.3 years. The other demographic data were similar. There were no significant differences in lumbar and femur neck BMD scores between 2 groups. Also, there were no associations neither between pregabalin use and biochemical markers including serum calcium levels nor between pregabalin use and vitamin D levels. However, the patients who had been used pregabalin less than 24 months had low lumbar t and z scores than patients who had been used pregabalin more than 24 months. This effect was more prominent in male patients. Although no negative effect of pregabalin was found on bone metabolism in these group of patients, we have suggested that further prospective controlled studies with large sample size in different age groups could provide new data about the effects of pregabalin on bone metabolism. We suggest to investigate the bone metabolism especially in male patients on pregabalin treatment who had been used pregabalin treatment less than 24 months.

Osteogenic Effect of Pregabalin in Human Primary Mesenchymal Stem Cells, Osteoblasts, and Osteosarcoma Cells

Seventy million patients worldwide are suffering from epilepsy. The long-term use of antiepileptic drugs causes the alteration of the bone tissue and its metabolism, thus increasing the risk of fractures. Clinical and pre-clinical studies have highlighted conflicting data on the influence of the relatively new antiepileptic drug pregabalin (Lyrica^®). The objective of the present study was therefore to investigate its cytotoxicity in primary human osteoblasts (hOB). HOB and human mesenchymal stem cells (hMSC) were isolated from patients. The human osteosarcoma cells MG63 were included as established cell line. Cells were incubated with pregabalin at concentrations ranging from 0 to 40 μg/mL. Time-dependent cell proliferation was measured by automatic cell counting, and metabolism was determined by XTT assay and osseous differentiation by alkaline phosphatase (ALP) activity. Histological examinations of calcium deposit were performed with ALP, Alizarin Red, and von Kossa staining. A concentration-dependent increase in the proliferation of hOB and hMSC was observed after treatment with pregabalin. All cells showed a significant increase in cell metabolism. The osteogenic differentiation, confirmed by the increase of calcium deposit, was promoted by the administration of pregabalin. This effect was already significant at the therapeutic plasma concentration of pregabalin (10 μg/mL). In contrast to the other antiepileptic drugs, pregabalin showed no osteocatabolic effects. Conflicting in-vivo data must therefore be attributed to systemic effects of pregabalin.