Effect of melatonin on neurological status and oxidative modification of proteins in experimental cerebral ischemia

Background. Ischemic stroke (IS) remains one of the leading causes of death and disability worldwide. Due to the limitations of oral and parenteral routes of neuroprotectant administration in post-stroke patients, the use of rectal suppositories with melatonin (MT) is a promising direction for neuroprotective therapy.

Aim. To evaluate the effect of rectal suppositories containing MT on the dynamics of neurological status and products of oxidative protein modification in experimental acute cerebral ischemia (EACI).

Materials and methods. Male Wistar rats (n = 30) were divided into 3 groups: I – sham-operated animals; II – animals with EACI according to the method of Chen S.T. et al.; III – animals with EACI that received rectal suppositories weighing 100 mg, containing 2.5 mg of MT. Neurological status was assessed on days 3 and 7 using the Garcia J.N. scale, the paw placement test, and the Bederson test. In the ischemic focus of the brain (IFB), the content of early and late products of protein oxidative modification (POM) was evaluated.

Results. In rats with EACI, neurological deficits developed on the corresponding day (decreased scores on the Garcia J.N. scale and the paw placement test, increased scores on the Bederson test) and an increase in the content of POM products in the IFB. Administration of MT suppositories contributed to the regression of these disorders: by day 7, there was an improvement in all neurological tests, and a decrease in POM products in the IFB.

Conclusions. The results obtained suggest that the neuroprotective effect of MT in the form of rectal suppositories in EACI is mediated through an antioxidant mechanism of action.

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