Amiodarone is the most commonly used class III antiarrhytmic drug with antiarrhytmic and vasodilator properties. Adenosine triphosphate (ATP) serves as a crucial source of intracellular energy, while resveratrol is known for its potent antioxidant activity. This study aimed to biochemically, histopathologically and immunohistochemically evaluate the effects of ATP, resveratrol and their combination on potential liver damage and dysfunction induced by amiodarone in rats. The rats were divided into 6 groups: healthy control (HG), amiodarone alone (ADG), amiodarone + ATP at 2 mg/kg (AAG-2), amiodarone + ATP at 5 mg/kg (AAG-5), resveratrol + amiodarone (RAG), and resveratrol + amiodarone + ATP at 2 mg/kg (RAA-2). Amiodarone (50 mg/kg, orally), ATP (2 mg/kg and 5 mg/kg, intraperitoneally) and resveratrol (25 mg/kg, orally) were administered once daily for 14 days. Following treatment, liver tissues were excised for biochemical analysis. Oxidative stress was assessed by measuring malondialdehyde (MDA) levels, while antioxidant status was evaluated through total glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) levels. To assess liver function, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were measured in serum samples collected from the animals' tail veins. In addition, liver tissues were subjected to histopathological and immunohistochemical examination to evaluate structural and molecular changes associated with treatment. Amiodarone administration led to a significant increase in oxidative stress markers and a reduction in antioxidant levels in rat liver tissue. Additionally, serum levels of ALT and AST were elevated, indicating liver dysfunction. Histopathological and immunohistochemical analyses revealed severe (grade 3) oxidative damage in the liver tissue. All biochemical parameters in the 5 mg/kg ATP and resveratrol + 2 mg/kg ATP treatment groups were comparable to those observed in the HG group. Histopathological and immunohistochemical evaluations showed a reduction in liver damage severity to grade 2 in the groups treated with ATP (2 mg/kg) and resveratrol alone, and to grade 1 in the groups receiving ATP (5 mg/kg) or the combination of resveratrol + ATP (2 mg/kg). The results of the present study suggest that adjusting the ATP dosage or using a combination of ATP and resveratrol may be effective strategies for minimizing amiodarone-induced liver damage.

Background: Amiodarone is a widely used class III antiarrhythmic agent, but its use can lead to peripheral neuropathy mediated by mitochondrial dysfunction, oxidative stress, and neuroinflammatory injury, while effective preventive options remain limited. Agents that support mitochondrial energy metabolism, sustain redox balance, and modulate inflammation, including adenosine triphosphate (ATP), melatonin, and thiamine pyrophosphate (TPP), may counteract these mechanisms; however, their relative neuroprotective potential in amiodarone-induced neuropathy remains unclear. This study aimed to comparatively evaluate the effects of ATP, melatonin, and TPP on amiodarone-induced peripheral neuropathy and neuropathic pain in rats. Methods: Thirty male albino Wistar rats were assigned to five groups: healthy; amiodarone (50 mg/kg/orally); amiodarone + ATP (5 mg/kg/intraperitoneally); amiodarone + melatonin (10 mg/kg/orally); or amiodarone + TPP (20 mg/kg/intraperitoneally). Treatments were given once daily for 14 days. Oxidative stress indices (malondialdehyde (MDA), total glutathione (tGSH), superoxide dismutase (SOD), catalase (CAT)) and proinflammatory cytokines (tumor necrosis factor-alpha (TNF-α), interleukin-1 Beta (IL-1β), interleukin-6 (IL-6)) were quantified in sciatic nerve by Enzyme-Linked Immunosorbent Assay (ELISA). Paw withdrawal thresholds were measured with the Randall-Selitto test before and after treatment. Histopathology was performed using Hematoxylin-eosin staining. Results: Amiodarone exposure resulted in pronounced elevations in MDA and proinflammatory cytokine levels, accompanied by significant reductions in tGSH, SOD, CAT activities, and paw withdrawal thresholds. ATP, melatonin and TPP ameliorated these alterations to varying degrees. Among them, TPP provided the most robust antioxidant and anti-inflammatory effects, followed by ATP and melatonin. Histopathological examination confirmed most severe axonal degeneration, interstitial edema and Schwann cell proliferation in the amiodarone group, with substantial amelioration in the TPP-treated rats. Conclusions: Amiodarone induces neuropathic pain through oxidative and inflammatory injury to peripheral nerves. TPP exhibited superior neuroprotective efficacy compared with ATP and melatonin, highlighting its potential as a candidate therapeutic agent for amiodarone-related neuropathy. Further clinical research is warranted to support translational application of these findings.

Background/Objectives: Linezolid is an oxazolidinone antibiotic whose prolonged use is associated with peripheral neuropathy, hyperlactatemia, and metabolic acidosis. These adverse effects are primarily linked to the inhibition of mitochondrial protein synthesis, respiratory chain dysfunction, and oxidative stress. Given the central role of impaired energy metabolism and redox imbalance in drug-induced peripheral neuropathy, therapeutic strategies targeting mitochondrial function are of particular interest. Accordingly, this study aimed to comparatively evaluate the effects of adenosine triphosphate (ATP), coenzyme Q10 (CoQ10), pyridoxine, and thiamine pyrophosphate (TPP) on linezolid-induced peripheral neuropathic pain in rats. Methods: Sixty male albino Wistar rats were assigned to ten groups: healthy (HG); ATP-only (ATPG, 5 mg/kg, intraperitoneally); CoQ10-only (CQ10G, 10 mg/kg, orally); pyridoxine-only (PDXG, 50 mg/kg, orally); TPP-only (TPPG, 20 mg/kg, intraperitoneally); linezolid-only (LZDG, 125 mg/kg, orally); linezolid+ATP (ATLG); linezolid+CoQ10 (CQLG); linezolid+pyridoxine (PXLG); and linezolid+TPP (TPLG). Treatments were administered once daily for ATP, CoQ10, and TPP, and twice daily for linezolid and pyridoxine for 14 days. Oxidative stress indices (MDA, tGSH, SOD, CAT) were quantified in the sciatic nerve using ELISA. Serum lactate dehydrogenase (LDH) activity and blood lactate levels were determined to evaluate metabolic disturbances. Mechanical paw withdrawal thresholds were measured using the Randall–Selitto test both before and after treatment. Results: Linezolid significantly reduced paw withdrawal thresholds and induced oxidative stress, antioxidant depletion, increased LDH activity, and hyperlactatemia. Co-treatment with ATP and CoQ10 attenuated oxidative stress but did not significantly improve linezolid-induced reductions in nociceptive thresholds. In contrast, pyridoxine partially alleviated linezolid-induced neuropathic pain and improved biochemical parameters. Notably, TPP exerted the most robust protective effect, preserving nociceptive thresholds and effectively normalizing oxidative stress and metabolic indices. Conclusions: These findings identify TPP as a promising therapeutic strategy for mitigating linezolid-induced peripheral neuropathic pain by targeting mitochondrial energy metabolism and pyruvate–lactate homeostasis.

Linezolid, a synthetic antimicrobial agent, may induce oxidative damage in ocular tissues, particularly in the optic nerve. Adenosine triphosphate (ATP) is involved in the production of antioxidants that scavenge and neutralize reactive oxygen species. This study aims to evaluate the potential protective effect of exogenous ATP against linezolid-induced ocular damage in rats, in comparison with methylprednisolone. Wistar-type rats were divided into five groups as follows: healthy (HG), ATP-only (ATPG), linezolid-only (LZDG), ATP + linezolid (ATLDG), and methylprednisolone + linezolid groups (MPLDG). Oxidative stress markers, antioxidant biomarkers, and proinflammatory cytokines were analyzed in isolated ocular tissues. Optic nerve tissue was also evaluated histopathologically. Linezolid administration increased the oxidative stress marker MDA and the proinflammatory cytokine TNF-α, while decreasing antioxidant parameters such as tGSH, SOD and CAT in rat ocular tissues, compared to the healthy group. However, it did not significantly alter serum troponin I levels. Histopathological analysis revealed that linezolid induced oxidative damage and inflammation in optic nerve tissue, with marked glial alterations. ATP administration reduced linezolid-induced oxidative stress in ocular tissue, as indicated by decreased MDA levels. It also enhanced antioxidant defenses by increasing tGSH, SOD, and CAT levels. In addition, ATP lowered proinflammatory cytokine levels, thereby alleviating inflammation. These effects collectively contributed to the restoration of biochemical parameters toward normal levels. In addition, ATP mitigated linezolid-induced optic nerve damage and glial alterations. The critical role of ATP in reducing oxidative stress, restoring antioxidant balance, and suppressing inflammation may represent a promising therapeutic approach for linezolid-induced ocular toxicity.

Background: Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) such as erlotinib are widely used in non-small-cell lung cancer treatment, and accumulating evidence indicates they can markedly increase ocular toxicity. Nonetheless, whether erlotinib causes optic nerve injury has not been investigated before and remains a subject worth investigating. This study aimed to examine the impact of erlotinib on oxidative stress, inflammation, and histopathological changes in rat optic nerve tissue and evaluate the potential neuroprotective role of thiamine pyrophosphate (TPP). Methods: Twenty-four male Wistar rats were randomly assigned to four groups: healthy control, TPP alone, erlotinib alone, and erlotinib + TPP. Erlotinib (10 mg/kg, orally, on alternate days) and TPP (20 mg/kg, intraperitoneally, daily) were administered for two consecutive weeks. Optic nerve samples were analyzed for malondialdehyde (MDA), total glutathione (tGSH), superoxide dismutase (SOD), catalase (CAT), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α), followed by histopathological examination. Results: Erlotinib treatment significantly increased MDA, IL-1β, and TNF-α levels while reducing tGSH, SOD, and CAT activity, demonstrating oxidative stress and an inflammatory response. Co-administration of TPP ameliorated these changes by lowering reactive oxygen species, restoring antioxidant capacity, and attenuating inflammation. Histopathological alterations, including astrocyte degeneration, edema, and vascular congestion, were evident after erlotinib exposure but were significantly alleviated when TPP was administered concurrently. Conclusions: Erlotinib induces oxidative and inflammatory optic nerve injury, while TPP co-treatment offers significant neuroprotection. These findings support TPP as a potential adjunct to reduce EGFR-TKI-related ocular toxicity and highlight importance of redox modulation in limiting treatment-associated side effects.