[Melatonin reverses oxidative damage in the submandibular gland of rats treated with Cyclophosphamide]. / Melatonina revierte el daño oxidativo en glándula submandibular de ratas tratadas con Ciclofosfamida.

Objetive: Cyclophosphamide (Cf) produces oxidative damage in rat submandibular gland (GSM). In the present work we evaluated the antioxidant protective effect of melatonin (MLT) in GSM of rats treated with Cf. Methods: 40 adult male Wistar rats were divided into 5 groups (G): G1: control; G2: Control+Ethanol: treated with 1% ethanol for 10 consecutive days. On days 11 and 12 they received a dose of saline; G3: Cf: treated with 1% ethanol for 12 days, days 11 and 12 they received an intraperitoneal (i.p.) dose of Cf 50 mg/Kg/kg of saline. ) of Cf 50 mg/kg bw; G4: Cf + MLT: MLT (5 mg/kg bw, intraperitoneal, dissolved in 1% ethanol) was administered daily, days 11 and 12 received Cf same as G3; G5: MLT: treated 12 consecutive days with MLT (same dose as G4). After 12 hours of fasting, animals were anesthetized to obtain both submandibular glands, then they were sacrificed. Uric acid (UA), lipid peroxides (LPs), aqueous peroxides (APs) and superoxide dismutase (SOD) activity were measured in submandibular gland homogenate. Statistical analysis: we used ANOVA and Bonferroni test pos hoc, considering significant p<0.05. Results: Cf treatment decreased AU concentration and SOD activity (AU, mg/mg prot., G1: 2.50±0.68; G2: 2.18±0.13; G3: 0.54±0.09* G4: 1.95±0.24#, G5: 2.64±0.47, *p<0.01 G3 vs G1, G2, G4; #p<0.01 G4 vs G3 and G5; SOD, U/mg prot, G1: 4.57±0.95, G2: 4.79±0.94, G3: 2.18±0.53*, G4: 5.13±1.10, G5: 5.09±0.39, *p< 0.01 G3 vs G1, G2, G4 and G5). MLT treatment prevented these effects. In addition, Cf increased PL and PA formation. Conclusion: MLT improved the redox status in GSM of Cf-treated rats. MLT could prevent oxidative processes in GSM produced by Cf.

Objetivo: Ciclofosfamida (Cf) produce daño oxidativo en glándula submandibular (GSM) de ratas. En el presente trabajo se evaluó el efecto protector antioxidante de melatonina (MLT) en GSM de ratas tratadas con Cf. Método: Se utilizaron 40 ratas Wistar machos adultas divididas en 5 grupos (G): G1: control; G2: Control+Etanol: tratados con etanol al 1% durante 10 días consecutivos. Los días 11 y 12 recibieron una dosis de solución salina; G3: Cf: tratados con etanol al 1% durante 12 días, días 11 y 12 recibieron una dosis intraperitoneal (i.p.) de Cf de 50 mg/Kg de pc; G4: Cf + MLT: se administró diariamente MLT (5 mg/Kg pc, intraperitoneal, disuelta en etanol al 1%), días 11 y 12 recibieron Cf igual que G3; G5: MLT: tratamiento 12 días consecutivos con MLT (igual dosis de G4). Los animales fueron anestesiados, extirpándose ambas GSM y sacrificados, previo ayuno 12 hs. Se midió la concentración de ácido úrico (AU), peróxidos lipídicos (PL) y acuosos (PA) y actividad de superóxido dismutasa (SOD) en homogenato de GSM. Análisis estadístico: ANOVA y test de bonferroni, considerando significativo p<0,05. Resultados: El tratamiento con Cf disminuyó la concentración de AU y la actividad de SOD (AU, mg/mg prot., G1: 2,50±0,68; G2: 2,18±0,13; G3: 0,54±0,09* G4: 1,95±0,24#, G5: 2,64±0,47, *p< 0,01 G3 vs G1, G2, G4; #p< 0,01 G4 vs G3 y G5; SOD, U/mg prot., G1: 4,57±0.95, G2: 4,79±0,94, G3: 2,18±0,53*, G4: 5,13±1,10, G5: 5,09±0,39, *p< 0,01 G3 vs G1, G2, G4 y G5). El tratamiento con MLT previno esos efectos. Además, Cf aumentó la formación PL y PA. Conclusión: MLT mejoró el estado redox en GSM de ratas tratadas con Cf. MLT podría prevenir los procesos oxidativos en GSM producidos por Cf.

[Determination of some oxidative stress, functional and immunological markers in the saliva of patients undergoing bone marrow transplantation (BMT).] / Determinación de algunos marcadores de estrés oxidativo, funcionales e inmunológicos en saliva de pacientes sometidos a trasplante de médula ósea (TMO).

OBJECTIVE: High doses of chemotherapy used prior to bone marrow transplantation (BMT) promote severe changes in the stomatognathic system. The objective of the present work consisted in evaluating some functional, immunological and oxidative stress markers in saliva of these patients. METHODS: A longitudinal observational study was carried out on 22 patients admitted to the Bone Marrow Transplant Unit of the Oncohematology Service of the Sanatorio Allende between March 2019 and February 2020. Basal saliva collection was carried out in the initial stage (I ) prior to isolation and middle stage (M) 14 days after conditioning therapy and transplantation. The concentration of uric acid (UA), superoxide dismutase (SOD), malondialdehyde (MDA), salivary alpha amylase, secretory immunoglobulin A (Ig As), lactoferrin, ceruloplasmin and urea were analyzed. RESULTS: In (M) the levels of SOD and MAD increased significantly compared to (I) (p <0.01). The concentration of salivary alpha amylase, Ig As, lactoferrin and uric acid was significantly lower in (M) compared to (I ) p <0.0001, p <0.01, p <0.0001, p <0.02 respectively. Ceruloplasmin and Urea did not show variations during treatment. CONSLUSION: In the present study, a decrease in the defensive capacity of saliva was observed as a consequence of a reduction in the concentration of Ig As and lactoferrin. The increase in SOD in (M) could be interpreted as a defense mechanism of saliva against oxidative stress produced by chemotherapy. The decrease in uric acid in stage (M) could allow the worsening of mucositis. The synthesis and release of amylase was affected by treatment with cytostatic drugs.

OBJETIVO: Altas dosis de quimioterapia utilizadas previo al trasplante de médula ósea (TMO) pueden promover severos cambios en el sistema estomatognático. El objetivo consistió en evaluar algunos marcadores funcionales, inmunológicos y de estrés oxidativo en saliva de pacientes sometidos a dicho tratamiento. MÉTODOS: Estudio observacional longitudinal en 22 pacientes de la Unidad de trasplante de Médula Ósea del Servicio de Oncohematología del Sanatorio Allende. Se efectuó recolección de saliva basal en etapa inicial (I) previa al aislamiento y etapa media (M) 14 días posteriores a la terapia de acondicionamiento y trasplante. Se analizó la concentración de ácido úrico (AU), superóxido dismutasa (SOD), malondialdehido (MDA), alfa amilasa salival, inmunoglobulina A secretora (Ig As), lactoferrina, ceruloplasmina y urea. RESULTADOS: En (M) los niveles de SOD y MAD aumentaron significativamente respecto de (I) (p< 0.01). La concentración de  alfa amilasa salival, Ig As, lactoferrina y ácido úrico fue significativamente menor en (M) respecto de ( I ) p < 0.0001, p < 0.01, p < 0.0001, p <0.02 respectivamente. Ceruloplasmina y Urea no mostraron variaciones. CONCLUSIÓN: se observó una disminución de la capacidad defensiva de la saliva como consecuencia de una reducción de la concentración de Ig As y lactoferrina. El incremento de SOD en (M) podría interpretarse como un mecanismo de defensa de la saliva contra el estrés oxidativo producido por la quimioterapia. La disminución de ácido úrico en la etapa (M) podría favorecer el agravamiento de mucositis.  La síntesis y liberación de amilasa fue afectada por el tratamiento con citostáticos.

Mucositis and salivary antioxidants in patients undergoing bone marrow transplantation (BMT).

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.

Analysis of saliva samples from oncological patients treated with 5-fluorouracil and leucovorin calcium by scanning electron microscopy with energy dispersive system.

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.