Protective effects of taxifolin on pazopanib-induced liver toxicity: an experimental rat model.

Pazopanib is a tyrosine kinase inhibitor that is generally used for the treatment of metastatic renal cell cancer and advanced soft tissue sarcoma. It can cause various degrees of hepatotoxicity. Our study aimed to investigate the effect of taxifolin on pazopanib-induced liver toxicity. A total of 18 rats were divided into three groups: the pazopanib (PP), pazopanib plus taxifolin (TPP), and control (C) group. Taxifolin was administered to the TPP (n=6) group with a dose of 50 mg/kg. Distilled water was orally admnistered to the C (n=6) and PP (n=6) groups as a solvent. Subsequently, pazopanib 200 mg/kg was administered to the TPP and PP groups via the stomach. This procedure was repeated once a day for four weeks. Then, all rats were sacrificed, and their livers were removed. Malondialdehyde (MDA), total glutathione (tGSH), total oxidant status (TOS), and total antioxidant status (TAS) levels were evaluated. MDA and TOS levels were higher in the PP group compared with the levels of the other parameters (P<0.001). tGSH and TAS levels were lower in the PP group than in the TPP and C groups (P<0.001), and the aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) levels were higher. Furthermore, liver tissue damage, including hemorrhage, hydropic degeneration, and necrosis was observed in the PP group. Administration of taxifolin before pazopanib significantly improved degenerative changes. Our study demonstrated that the administration of taxifolin is significantly effective in preventing pazopanib-induced hepatotoxicity in rats.

Effects of adenosine triphosphate on vandetanib induced skin damage in rats.

PURPOSE: Vandetanib is a wide spectrum tyrosine kinase inhibitor used for the treatment of metastatic medullary thyroid cancer (MTC) and various other cancer types. Although it is usually well-tolerated it has been linked to a variety of severe dermatologic reactions. Our study aimed was to investigate adenosine 5'-triphosphate (ATP) on vandetanib-induced skin damage. MATERIALS AND METHODS: A total number of 18 rats were divided into three equal groups as vandetanib group (VDB), vandetanib plus ATP group (VAT), and healthy group (HG); 25 mg/kg ATP was injected intraperitoneally (ip) to the VAT group. Normal saline was given to the HG and VDB groups as solvent via intraperitoneally. One hour later, 25 mg/kg vandetanib was applied orally via an orogastric catheter in the VAT and VDB groups. This procedure was repeated once daily for 4 weeks. After that period, all animals were sacrificed and their skin tissues removed. Malondialdehyde (MDA), total glutathione (tGSH), total oxidant status (TOS), total antioxidant status (TAS) levels in rats' skin tissues were evaluated with histopathological analyses. RESULTS: MDA and TOS levels measured higher in the VDB group compared to the VAT and HG groups (p < 0.001). tGSH and TAS levels of the VDB group measured lower than the VAT and HG groups (p < 0.001). The structure and morphology of skin tissue were normal in the control group. In the VDB group, skin tissue damage with thinner epitelium, ruptured and degenerated hair follicles, abnormal accumulation of abnormal keratin on the epithelium and oedematous areas in the dermis was observed. In the VAT group, these findings were significantly improved. CONCLUSION: We demonstrated that adenosine triphosphate can prevent vandetanib-induced skin toxicity in rats for the first time. The promising results denote that further studies testing this agent in other animal models and in humans are warranted.

Effects of anakinra on the small intestine mucositis induced by methotrexate in rats.

Intestinal mucositis is an important problem in the patients receiving cancer treatment. We aimed to investigate the effect of anakinra, which is a well known anti-oxidant and anti-inflammatory agent, on methotrexate-induced small intestine mucositis in rats. Forty rats were divided into 4 groups with 10 in each group. The healthy group (HG) and the methotrexate group (MTXG) were given distilled water, while the methotrexate + anakinra 50 (MTX+ANA50) and the methotrexate + anakinra 100 (MTX+ANA100) groups were intraperitoneally administered 50 and 100 mg/kg of anakinra. After one hour, the MTXG, MTX+ANA50 and MTX+ANA100 groups were given oral methotrexate at a dose of 5 mg/kg. This procedure was repeated once a day for 7 days. After the rats had been sacrificed, the small intestine tissue of rats were removed for the assesment of biochemical markers, histopathological evaluation and gene expression analyze. Statistical analyses of the data were performed using one-way ANOVA. Malondialdehyde (MDA), myeloperoxidase (MPO) and interleukin-6 (IL-6) levels were significantly higher, whereas total glutathione (tGSH) levels were significantly lower in MTXG (P<0.001) compared to other groups. MTX also increased IL-1ß and TNF-α gene expression levels in MTXG (P<0.001). Inflammatory cell infiltration and damage to the villus were observed histopathologically in the MTXG group, whereas only mild inflammation was seen in the MTX+ANA100 group. A dose of 100 mg/kg of anakinra prevented the increase of the biochemical markers and gene expression levels better than a dose of 50 mg/kg. Intestinal mucositis caused by MTX may be preventible by co-administered anakinra.