Short-term incubation of gabapentin or pregabalin does not affect chemically induced injury in neuronal cell models in vitro

Abstract

PurposeGabapentinoids are currently the mainstay of pharmacological treatments for patients with neuropathic pain. Little is known about the effects of this therapy on the integrity of neuronal networks, especially in patients with an already-damaged nervous system. Since gabapentinoids can worsen cognitive functions and recent studies have shown alterations in the brains of patients with neuropathic pain, it may be possible that these drugs have neurotoxic effects.MethodsRat clonal PC12 pheochromocytoma (autonomic) and primary sensory dorsal-root ganglion (DRG) neurons from newborn Wistar rats were employed for this study. To mimic neuronal damage, cells were exposed to cytotoxins using either hydrogen peroxide (H2O2) or vincristine.ResultsNo direct cytotoxic effects were observed after incubating PC12 cells for 24 hours with increasing concentrations of gabapentin or pregabalin using MTT cytotoxicity assays. Even a 7-day incubation did not cause cellular damage. Furthermore, in preinjured PC12 and DRG neurons, neither gabapentin nor pregabalin prevented or enhanced the cytotoxic effects of H2O2 or vincristine after incubation for 24 hours and 7 days, respectively. Cell morphology and integrity of the cytoskeleton assessed by employing immunostaining of cytoskeletal proteins (α-tubulin, neurofilament L) remained intact and were not altered by gabapentinoids.ConclusionBased on these results, gabapentinoids are unlikely to be neurotoxic in cultured autonomic (PC12) and sensory DRG cells, even when cells are preinjured. These results are of high clinical relevance, as it seems unlikely that the morphological changes recently observed in the brains of neuropathic pain patients are caused or worsened by gabapentinoids.

Concomitant Antihyperalgesic and Antitumor Effects of Gabapentin in a Murine Cancer Pain Model

“…In this study, the cytostatic effect of gabapentin was determined using 2000 µg/mL as the highest dose—which is equivalent to 11.68 µM—and compared to the control cell cultures without gabapentin. According to a recent study [ 81 ], this concentration is similar to a third of the maximum daily dose of gabapentin (3600 mg). Cell proliferation was monitored 96 h later using an inverted fluorescence microscope (DMIL LED, Leica Microsystems) coupled with a camera (DFC310 FX, Leica Microsystems).…”

“…Murine B16–BL6/Zs green melanoma cells were seeded into 96-well flat-bottom tissue culture microplates (1 × 10 3 cells/well, Falcon, Becton Dickinson, NJ, USA) and incubated for 24 h to allow adherence to the plate. Thereafter, six different concentrations of the drug (1, 10, 50, 100, 1000, or 2000 mg/mL) were tested ( Figure 9 ); these concentrations were chosen based on previous works [ 79 , 80 , 81 ]. According to pharmacokinetic studies, after the administration of a 400-mg gabapentin tablet to a human, its maximum concentration in plasma reached approximately 20 µM [ 80 ].…”

A Brief Review of In Vitro Models for Injury and Regeneration in the Peripheral Nervous System

“…CIPN commonly occurs as an undesirable, dose-limiting effect of several chemotherapeutics such as cisplatin, paclitaxel [ 143 , 144 ], vinblastine, and vincristine [ 145 ], mainly due to chemically induced damage to axons and cell bodies of peripheral neurons. Though the underlying mechanism of CIPN is not completely known, axonal degeneration or ‘dying back’ is a well-recognized histopathological hallmark [ 27 , 146 ], and understanding the molecular mechanism behind such pathogenesis is crucial to develop therapeutic strategies. In vitro models, especially using dissociated DRG cultures, have been utilized to understand the key cellular features of CIPN.…”