Objectives: High doses of chemotherapy generate DNA damage in patients undergoing bone marrow transplantation (BMT), due to the production of reactive oxygen species (ROS). In order to evaluate the local defensive effectiveness of the patient undergoing BMT, the concentrations of the antioxidants superoxide dismutase (SOD) and uric acid (UA) were measured in saliva. Study Design: Basal saliva samples were collected from 20 patients undergoing BMT at the Oncology Department, Sanatorio Allende (Córdoba), in the stages: initial, prior to conditioning therapy (I); middle: 7 to 10 days after BMT (M) and final stage, 30 days after discharge from isolation (F). SOD levels were determined using a RANDOX kit (RANSOD superoxide dismutase manual), and for uric acid enzymatic UOD / PAP spectrophotometric method, ( Trinder Color Kit , Wiener Lab) was used. Results: 85% of the patients developed oral mucositis. SOD concentration in the M stage was significantly higher (p<0.01) compared with stage I, and it reversed in stage F. UA concentration was significantly lower (p<0.001) in stage M compared with stage I, and in stage F it recovered the initial values. Conclusions: SOD increase in stage M coincided with the appearance of mucositis, which could be interpreted as a defensive mechanism of saliva against oxidative stress produced by chemotherapy. UA decrease in stage M would favour the development of higher degrees of mucositis. Key words:Bone marrow transplantation, mucositis, superoxide dismutase, uric acid.

This work presents a chemical and morphological analysis of samples of saliva taken from patients who were under treatment with intravenous chemotherapy with 5-fluorouracil and leucovorin calcium. Samples of saliva were extracted from fifteen patients during the three stages of the treatment: The initial stage (previous to the chemotherapy), the intermediate stage (during the chemotherapy), and the final stage (twenty-one days after finishing the treatment). An amount of 50 μl was collected in each visit. Chemical contrast images were taken by means of scanning electron microscopy, and X-ray characteristic spectra were obtained from all the studied samples by using an energy dispersive system from all the studied samples. Images that correspond to the intermediate stage showed important differences with respect to the initial and final stages. In addition, X-ray spectra provided information about the present elements in saliva and their relative abundance allowed us to determine variations in the chemical composition. The backscattered electron images and X-ray spectra from the intermediate stage showed clusters of crystals with fluorine content higher than those obtained in initial and final stages. This fact probably indicates the passage of metabolites of 5-fluorouracil and leucovorin calcium from the plasma to the oral cavity. This finding enhances the hypothesis proposed by other authors about the secondary effects of the drugs on the stomatognathic system such as oral mucositis, dysgeusia, and xerostomia with or without hyposalivation.

Objective: Chemotherapy treatment against cancer produce systemic toxicities, among which are those related to important structures of the stomatognathic system and its functional activity. 5 Fluorouracil (5-FU) and cyclophosphamide (Cf) are drugs widely used in solid tumors and in bone marrow transplantation, respectively. The objective of this work was to evaluate the toxicity of these drugs regarding functional activity of the submandibular glands, by measuring the percentage of glycogen consumption in two experimental models. Material and Methods: 84 male Wistar rats aged three months were used, housed in individual cages, with controlled temperature and lighting and ad libitum diet. They were divided into four experimental groups: 1) Control (C); 2) Treated with 5-FU+leucovorin (LV) at 20 and 10mg/Kg of body weight respectively for five consecutive days; 3) treated with Cf i.p. at 50mg/Kg of body weight for two consecutive days; and 4) rats with paired feeding (PF): for five and two days respectively, the amount administered resulted from the average of the ingested food of groups 2 and 3. Both submandibular glands were excised. The submandibular glycogen concentration was analyzed at initial time (t0) and after 60 minutes of mechanical stimulation (t60). Results: the average variation changed significantly between time 0 and 60 in the groups C and PF. (p-value=0.0001), the 5-FU + LV treatment group had an average concentration higher at t0 than groups C and PF, without significant consumption at T60. While group Cf showed a lower average concentration at time 0 with respect to groups C and PF, without significant consumption at T60. Conclusion: 5-FU+LV and Cf affect the metabolism of carbohydrates, decreasing the use of glycogen as a metabolic substrate. In the present experimental model, the toxicity of these drugs affected the functional activity of the submandibular gland.

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Efecto de ciclofosfamida sobre el metabolismo de los hidratos de carbono en glándula submandibular de ratasEffect of cyclophosphamide on the metabolism of carbohydrates in the submandibular gland of rats AbstractObjective: During the period of chemotherapy, the appearance of serious systemic toxicities is one of the main clinical problems, among which are those related to the stomatognathic system. Cyclophosphamide is a drug widely used in solid tumors and bone marrow transplantation. The objective of this work was to evaluate the toxicity of cyclophosphamide on the functional activity of the submandibular glands of Wistar rats in an experimental model. Methods: We used 42 male Wistar rats aged 3 months, housed in individual cages, with temperature and controlled lighting and free diet. They were divided into three experimental groups: 1) Control (C), 2) treated with cyclophosphamide (Cf,) applying an i.p. of 50 mg / Kg of body weight during two consecutive days and 3) rats with paired feeding (AA): during two days the amount administered resulted from the average of the ingested food of group 2 .Both submandibular glands were removed. The submandibular glycogen concentration was analyzed in initial time (t0) and after 60 minutes of mechanical stimulation (t60). Results: The average variations changed significantly between time 0 and 60 in groups C and AA (p-value = 0.0001), Cf had a lower average concentration in time 0 with respect to C and AA, without significant consumption in time 60. Conclusion: Cf would affect the metabolism of carbohydrates, decreasing the use of glycogen as a metabolic substrate. In the present experimental model the toxicity of this drug reduces the functional activity of the submandibular gland.