Evaluation by different mechanisms of the protective effects of vitamin B12 on methotrexate nephrotoxicity.

Methotrexate is used for cure of many cancer types. It has many side effects. For this reason, obtaining a nephroprotective agent is obligatory. In the study, our aim is to determine probable effects of Vitamin B12 on MTX caused kidney damages in rats. Rats were randomly divided into 4 groups, including 8 animals in each group. Control group, VitB12 group (3 µg-kg-ip B12 throughout 15 days), MTX group (at the 8th day of experiment, a single dose of 20 mg-kg-ip MTX), Vit B12 + MTX group (3 µg-kg-ip B12 throughout 15 days and at the 8th day of experiment, a single dose of 20 mg-kg-ip MTX) Animals were anesthetized and kidney tissues were removed to evaluate biochemically, immunohistochemically and histopathologycally. There were histopathological deteriorations, rises of apoptotic cells, expressions of heat shock proteins, endoplasmic reticulum stress and inflammation markers in the MTX group. In the MTX group, Superoxide Dismutase (SOD), Total Antioxidant Status (TAS) and Catalase (CAT) levels decreased, but Total Oxidant Status TOS, Malondialdehyde (MDA) and interleukin-6 (IL6) levels increased. In addition, there was amelioration in kidney tissue in Vit B12 + MTX group compared to the MTX group. We suggest that Vit B12 can be used to reduce the toxic effects of MTX.

Histological, immunohistochemical and biochemical effects of bee bread on stomach tissue of obese rats.

Obesity is a major health problem threatening humanity in medical, social and psychological dimensions. In this study, we aimed to determine the histological, immunohistochemical and biochemical effects of bee bread, added to diets of obese rats in different doses, on leptin and ghrelin expression. In the study, 40 female Sprague‒Dawley (200‒250 g) rats were randomly divided into 5 equal groups and then assigned to control and obesity groups. The obesity group consisted of four subgroups: high­fat diet group, 100 and 200 mg/kg/bw groups, and metformin group. Histopathological evaluation revealed structural deterioration and necrotic areas in the epithelium and glands of the obese rats' stomach tissue, while in their serum and gastric tissues, the MDA level was significantly higher than in the other groups. There was a negative correlation between leptin and ghrelin levels. Apoptotic cells increased with obesity, but the application of beebread was similarly effective as metformin administration in reducing this increase (Tab. 5, Fig. 4, Ref. 51). Keywords: bee bread, leptin, ghrelin, stomach, obesity, rat.

Thymoquinone is a protective agent that reduces the negative effects of doxorubicin in rat testis.

BACKGROUND: Doxorubicin (DOX) is used for treatment of many cancer types. Thymoquinone (THQ) is a powerful antioxidant agent used for reducing side effects of several drugs. The aim of this study is to determine possible therapeutic effects of THQ on doxorubicin-induced testicular toxicity in rats. METHODS: Rats were divided into five groups (n = 8): control, THQ, olive oil, DOX (a single dose of 15 mg/kg intraperitoneally (i.p.) on seventh day of the experiment), and DOX + THQ (10 mg/kg THQ per day and 15 mg/kg DOX i.p. on seventh day). Animals were euthanized, and testis tissues were evaluated histopathologically. Caspase 3 and HSP90 immunostaining were performed to determine the expression levels of these proteins among groups. Terminal deoxynucleotidyl transferase 2'-deoxyuridine, 5'-triphosphate nick-end labeling method was used for evaluation of apoptotic index. Moreover, serum testosterone levels and total antioxidant status (TAS) and total oxidant status (TOS) in testicular tissue were measured by ELISA assay. RESULTS: The DOX group had histopathological deterioration compared to the control group. There was an increase in apoptotic index, caspase 3 and HSP90 expressions in the DOX group. While TAS level of the DOX group decreased, TOS level increased when compared with the other groups. Serum testosterone levels in the DOX group decreased compared to the control group. However, there was improvement in testicular tissue in DOX + THQ group compared to the DOX group. There was a decrease in apoptotic index, caspase 3, and HSP90 expressions in DOX + THQ group compared to the DOX group. Testosterone level of DOX + THQ significantly increased compared to the DOX group. CONCLUSION: We suggest that THQ can be used as a protective agent to reduce the toxic effects of DOX.

Acute effects of grayanotoxin in rhododendron honey on kidney functions in rats.

The aim of the study is to evaluate the acute biochemical and histological changes in rat kidneys after treatment with grayanotoxin (GTX) of rhododendron honey (RH). A total of 60 Sprague-Dawley female rats were divided into five groups of 12 rats each, one being a control group (group 1) and group 2 was treated with 0.015 mg/kg/bw of GTX standard preparation via intraperitoneal injection. Groups 3, 4, and 5 were given RH at doses of 0.1, 0.5, and 2.5 g/kg/bw, respectively, via oral gavage. Compared to the control group, significant increases were observed in glucose, blood urea nitrogen (BUN), and creatinine levels of the GTX-injected groups after 1 h. However, in low dose RH group, such an increase was not observed and had a normal appearance histologically. Therefore, low dose (1 g/kg/bw) of RH produces no acute adverse effects on renal functions of rats.

Coronal displacement of cementum: correlation between age and coronal movement of cementum in impacted teeth.

This study was conducted on 48 impacted and 51 erupted maxillary permanent canine teeth extracted from healthy patients aged 13-73 years. Longitudinal buccolingual ground sections were prepared. The distance between the edges of cementum and enamel in each specimen was measured with an eyepiece micrometer. A correlation test was applied between age and the distance between enamel and cementum measurements. In impacted teeth, depending on age, cementum had a tendency to overlap the enamel; there was a linear correlation between age and coronal displacement of cementum (n-2 = 46, r = 0.69, distance (microgram) = 21.7* age (years) -440, p < 0.001). No correlation between age and coronal displacement was found in erupted teeth (n-2 = 49, r = -0.23, p > 0.05). Results of the study indicated that the cementum in impacted teeth migrated coronally during the ageing process. This may be related to continually erupting forces which affect the impacted teeth and may be a mechanism by which the teeth are protected at the cemento-enamel junction (CEJ). This phenomenon could be used in forensic dentistry to determine age. The absence of correlation in erupted teeth could be attributed to the masking effects of extrinsic factors.

Effect of SC-41930, a potent selective leukotriene B4 receptor antagonist, in the guinea pig model of middle ear inflammation.

Arachidonic acid metabolites such as prostaglandins and leukotrienes have been shown to play an important role in the pathogenesis of otitis media (OM). Among these mediators, leukotriene B4 (LTB4) is one of the most potent inducers of inflammatory processes. SC-41930 has been shown to be a specific LTB4 receptor antagonist both in vitro and in vivo. In this study, anti-inflammatory effects of SC-41930 were investigated in a guinea pig model of OM induced by middle ear (ME) inoculation of killed Staphylococcus aureus. Outcome of treatment was determined by measurement of myeloperoxidase activity in the samples of ME mucosa, evaluation of temporal bone histopathology, and presence of ME fluids. Myeloperoxidase activity in the SC-41930-treated group was found to be significantly lower than that in the control group. Histopathology of temporal bones indicated decreased inflammation in the treated group as compared to the controls. In addition, ME fluids were absent in four out of six treated animals. These results demonstrate that SC-41930 can produce significant anti-inflammatory effects in this model of OM.