SUMMARY: Adriamycin (ADR) is an anthracycline antibiotic used for treatment of many types of cancer. However, its applications may damage to healthy tissues. Chloroquine (CLQ) is an anti-inflammatory agent used in treatment of many inflammation associated diseases such as malaria and rheumatoid arthritis. Moreover, it is used in the treatment of pneumonia caused by COVID-19. The aim of this study is to determine possible therapeutic effects of Chloroquine on Adriamycin-induced testicular toxicity in rats. We investigated the effect of CLQ on testicular injury caused by ADR. Rats were divided into four groups: Control, ADR, CLQ, ADR+CLQ. After administrations, animals were sacrificed, and testis tissues were extracted from the animals for the further examinations. Histopathological changes in testis tissues were evaluated and TNF-α and IL-6 immunostaining were performed to determine the expression levels of these cytokines. TUNEL method were used for evaluation of apoptotic index. Moreover, serum testosterone levels were measured by ELISA assay. We observed that ADR group showed histopathological deterioration when compared to the Control group and CLQ treatment ameliorated this damage induced by Adriamycin.An increase in TNF-α and IL-6 immunoreactivities and in the number of apoptotic cells and a decrease in serum testosterone levels were determined in the ADR group compared to the Control and CLQ group. Furthermore, our examinations showed an improvement in testicular tissue in ADR+CLQ group in terms of these parameters when compared to the ADR group. We suggest that CLQ can be used as a protective agent to reduce the toxic effects of Adriamycin as a result of its anti- inflammatory and anti-apoptotic properties.

KEY WORDS: Chemotherapy; Testis damage; TUNEL; IL-6; TNF-a.