Anti-apoptotic and antioxidant effects of melatonin protect spleen of whole body γ-irradiated male Sprague-dawley rats

Abstract

Background: Spleen is the largest lymphatic organ that is seriously affected during irradiation. Radiation exposure reduces both of spleen size and weight; that in turn decreases the numbers of immune cells. Melatonin is an effective free radicals scavenger. Therefore, this study aimed to evaluate the effects of melatonin on both blood and spleen of whole body γ-irradiated male Sprague dawley rats. Materials and methods: Animals were intraperitoneally injected with 100 mg/kg melatonin prior to radiation exposure by 30 minutes. Experimental groups were group I: control rats, group II: irradiated rats, group III: melatonin administrated unirradiated rats and group IV: melatonin administrated irradiated rats. Blood and spleen samples were collected 24 hours post irradiation for biochemical, immunological and blastogenesis measurements. Apoptosis, pro-and anti-apoptotic proteins of spleen cells were measured by flow cytometry techniques. Results: Melatonin significantly upregulated the activities of superoxide dismutase (SOD), glutathione (GSH) and catalase (CAT); and reduced malondialdehyde (MDA). It down regulated the expression of pro-apoptotic proteins (p53, Bax, caspase -3 and caspase-8) and up regulated the expression of anti-apoptotic protein Bcl-2 in spleen cells; that in turn reduced the radiation-induced apoptosis. Levels of pro-inflammatory cytokines (TNF-α, IFN-γ and IL-1β) were significantly reduced in group IV. Blastogenesis assay showed that melatonin protects PBMC and spleen B lymphocytes and stabilized their proliferation. Conclusion: Melatonin administration prior to whole body γ-radiation successfully protected rat's spleen from the consequences of radiation exposure. This was due to its free radicle scavenger nature, its reduction of lipid peroxidation and its anti-apoptotic effects.

Dual role of melatonin as an anti-colitis and anti-extra intestinal alterations against acetic acid-induced colitis model in rats

“…According to the current study, AA instillation in rats with colitis generated statistically significant rises in levels of IL-1β and TNF-α, which is similar to prior research by Ghasemi et al 40 . Due to increased epithelial permeability, luminal antigens penetrate the lamina propria layer and activate the mucosal immune system, resulting in an over-reaction of the mucosal immune system, which results in the excessive production of pro-inflammatory cytokines 41 – 45 .…”

Melatonin relieves diabetic complications and regenerates pancreatic beta cells by the reduction in NF-kB expression in streptozotocin induced diabetic rats

“…Sprague dawley male rats (10 weeks old; weighting; 170–220 g) were purchased from National Organization for Drug Control and Research (NODCAR, Cairo, Egypt). On arrival, rats were housed in conventional cages for one week before the experiment for acclimatization ( Ahmed et al, 2022 , Farid et al, 2013 , Farid et al, 2021 ). Rats were maintained at controlled temperature (21 ± 2 °C) and on a 12 h dark–light cycle.…”

Hazard Effects of Chronic consumption of Sucralose and Saccharin-Sodium Cyclamate Mixture in Murine Model

“…Animals were anesthetized by ether inhalation at the end of 8 weeks and 16 weeks intake of sweeteners. Blood was collected from jugular vein with EDTA (anti-coagulant) [9][10]. The non-coagulated blood was used to count red blood cells (RBCs), white blood cells (WBCs), platelet (PLT), and to measure haemoglobin (Hb) and haematocrit (HCT) percentage.…”

“…Specimens from liver, kidney, urinary bladder, and pancreas were fixed immediately in 10% neutral buffered formalin, dehydrated in different grades of alcohol, cleared in xylol, embedded in paraffin wax, sectioned at 4-6 μ thick and stained with haematoxylin and Eosin (H&E) according to Farid et al [9][10] and examined microscopically.…”