Investigating the effects of swimming exercise training on xidative stress induced by chronic morphine administration

Morphine as a strong analgesic compound is widely prescribed in clinic to control medium to severe pain, they are also may cause drug abuse. Recent studies have shown chronic morphine consumption and it could induce oxidative stress and cause cell damage. In this study, the effects of daily swimming exercise investigated on oxidative stress indices in the hippocampus and plasma of morphine dependent rats.

In this study, 48 adult male wistar rats were randomly divided to four groups. Experiments were done during January to March 2022 at Arak University of Medical Sciences. Morphine was self-administrated for 4 weeks, as dissolved (0.4 mg/ml) in the daily drinking water. Exercise training was included 15 minutes daily continuous swimming in a swimming pool. Swimming occurred during all days of morphine consumption. At the end, 6 rats were randomly selected from each group and withdrawal signs were evaluated by naloxone injection, to confirm morphine dependency. Then, hippocampus and plasma were collected from the 8 remaining rats of each group and were used for GSH, GSSG, MDA, irisin and BDNF assessment.

All rats in morphine consumed groups showed withdrawal signs in naloxone text, which means morphine dependency successfully were induced. However swimming exercise significantly reduced the consumption size of morphine. GSH was significantly decreased, while GSSG and MDA were significantly increased in the plasma and hippocampus of morphine groups in compare with control. Morphine consumption had no effect on plasma levels of irisin, while significantly decreased hippocampus level of BDNF. Daily swimming exercise in the morphine consumed group significantly repaired morphine effects on plasma and hippocampus levels of GSH, GSSG, MDA and hippocampus levels of BDNF.

Daily swimming exercise during the morphine consumption is able to repair at least some parts of the oxidative stress induced by morphine. This effect might help to reduce cellular and molecular damages raised by chronic morphine consumption.