The Effects of Co-administration of Immobilization Stress and Aloe vera on Serum Carcinoembryonic Antigen in Rats

Background: Immobilization has been used extensively and accepted widely for studying stress-induced alterations. To determine the protective effects of Aloe vera leaf extract, we evaluated the effects of co-administration of immobilization stress and Aloe vera leaf extract on serum level of carcinoembryonic antigen (CEA) tumor marker in male rats. Materials and Methods: In this experimental study, 45 male Wistar rats were randomly divided into 9 groups of 5 rats in each including: 1) control, 2) normal saline receiving, 3) Aloe vera extract receiving, 4) acutely immobilized, 5) chronically immobilized, 6) acutely immobilized+Aloe vera extract, 7) chronically immobilized+Aloe vera extract, 8) acutely immobilized+normal saline and 9) chronically immobilized+normal saline. The animals were exposed to chronic or acute immobilization stress for 2 h/day or 8 h/day for a period of 3 weeks or one week, respectively. Aloe vera extract (300 mg/kg/day) was fed by gavage feeding orally. Blood samples were collected and following serum collection, CEA level was determined by radioimmunoassay method. Data were compared statistically between groups using ANOVA. Results: Serum CEA level was significantly increased in acutely (0.640±0.025 ng/mL) or chronically immobilized (0.647±0.023 ng/mL) rats compared with control animals group (0.564±0.014 ng/mL) (p < 0.001). However, there was no significant difference between serum CEA levels of acutely or chronically immobilized Aloe vera extract received animals compared with control rats (0.622±0.027 ng/m and 0.616±0.044 ng/mL, respectively). Conclusion: Our findings indicate that immobilization stress enhances serum CEA level, however, intake of Aloe vera extract can withstand against.