Immunohistochemical neuroinflammatory markers in the hippocampus of PTZ-kindled rats under conditions of rapamycin and axitinib treatment

Abstract

The aim of the study is to determine the level of HIF-1α, TNF-α, and NF-kB in the hippocampus of kindled rats treated with rapamycin and axitinib. Materials and methods. Kindling was produced in 29 rats by administration of three-week pentylenetetrazole (PTZ, 35.0 mg/kg, i.p.). Treatment with rapamycin (0.5 mg/kg, i.p.) and axitinib (2.5 mg/kg, i.p.) was performed for ten days in fully kindled rats. The avidin-biotin-peroxidase method was used for hippocampal slice staining. For negative control, staining was performed using only secondary antibodies. Results. The HIF-1α expression increased in kindled rats raised by 1.77 times compared to the control (p<0.001). Axitinib treatment resulted in of HIF-1α level of 16.7 % (p<0.05) compared with kindled animals, while combined treatment with rapamycin and axitinib reduced HIF-1α by 33.8 % (p<0.01). In kindled rats, TNF-α expression was 3.74 times greater than in control (p<0.001). Rapamycin treatment reduced TNF-α by 31.0 % (p<0.01). Axitinib treatment caused a reduction of TNF-α by 21.1 % (p<0.05). Combined treatment with rapamycin and axitinib reduced TNF-α by 48.0 % (p<0.001) but still exceeded the TNF-α in control by 1.95 times (p<0.01). NF-kB level in kindled rats exceeded the control by three times (p<0.001). Rapamycin caused a reduction of 19.3 % (p>0.05), while axitinib – by 26.5 % (p<0.05) compared with kindled rats. Combined treatment with rapamycin and axitinib resulted in NF-kB reduction by 56.7 % compared with kindled rats (p<0.001).  Conclusions. PTZ-kindling resulted in an increase in the immunoreactivity of HIF-1α, TNF-α, and NF-kB in the hippocampus. Combined treatment with rapamycin and axitinib engendered prevention of generalized seizures and normalized the level of HIF-1α and NF-kB with a significant reduction of TNF-α. Effects of treatment favours of synergy action of rapamycin and axitinib