6TH INTERNATIONAL EURASIAN CONFERENCE ON BIOLOGICAL AND CHEMICAL SCIENCES, Ankara, Türkiye, 11 - 13 Ekim 2023, ss.226
One of the reasons that reduces the effectiveness of radiotherapy is that radiation can increase the survival rate
of cancer cells by stimulating autophagy in various types of cancer. Chloroquine (CQ), which has been used
in the treatment of malaria for many years, has been shown to inhibit autophagy in recent years. Apocynin
(APO) is a substance known as an effective NADPH oxidase inhibitor with antioxidant and antiapoptotic
properties. In our study, it was aimed to determine how the use of CQ together with radiotherapy will affect
healthy tissues and to reveal whether APO shows protective effects with this combination. Randomly selected
animals were divided into eight groups: Control, radiation (RAD), CQ, APO, RAD+CQ, RAD+APO,
RAD+CQ+APO and CQ+APO, respectively. The first and second groups were injected saline, the third and
fifth groups were injected 50 mg/kg CQ, the fourth and sixth groups were injected 20 mg/kg APO, the seventh
and eighth groups were injected with CQ and APO. All injections were administered intraperitoneally (i.p.)
five times every 24 hours for 5 days. One hour after the fifth injection, 8 Gray (Gy) whole body irradiation
was applied to the radiation groups. Small intestinal tissues were obtained from dissected rats one day after
radiation administration. As a result of our study, radiation causes significant histological damage, causes a
significant increase in oxidative damage parameters, weakens the antioxidant system, has antiproliferative,
inflammatory and apoptotic effects, and also stimulates autophagy are determined. CQ given together with
RAD inhibits autophagy, increases oxidative stress, weakens antioxidant capacity, has antiproliferative and
anti-inflammatory effects, and does not cause a significant change in apoptosis alone are observed. The fact
that APO significantly reverses these changes caused by RAD and CQ shows its protective effect. We
anticipate that our results may shed light on clinical applications.