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Background and Objective: Immobilization stress has a variety of effects on the enzymes activity. This study was conducted to determine the protective effect of Aloe vera extract on the serum level of creatine kinase enzyme in male rates exposed to acute and chronic immobilization stress. Materials and Methods: This experimental study was conducted on 45 male Wistar rats weighing approximately 200±30g. Animals were randomly allocated into 9 groups of 5 rats: control, normal saline, chronically immobilized, acutely immobilized, chronically immobilized normal saline, acutely immobilized normal saline, Aloe vera extract (600mg/kg/daily), acutely immobilized Aloe vera (600g/kg/daily) and chronically immobilized Aloe vera groups (600g/kg/daily). Aloe vera extract with a dose of 600mg/kg/BW was administered by gavage feeding before applying stress. For chronic immobilization, animals were put under immobilization stress for 2 hrs a day for 3 weeks and for acute immobilization animals were put under immobilization for 8hrs a day for one week. At the end of the experiments, blood samples were collected using cardiac puncture method and serum level of creatine kinase enzyme (units/L) was measured by spectrophotometery. Data were analyzed using SPSS-19, one-way ANOVA and Tukey post-hoc tests. Results: Serum level of creatine kinase enzyme represented a statistical significant increase in rats exposed to acute (2368.20±104.96 units/L) and chronic immobilization (2177.80±234.75 units/L) compared with control group (1240.40±706.40 units/L) (P<0.001). The enzyme alteration level was not significant in Aloe vera (1619.80±171.41 units/L), acutely immobilized Aloe vera extract (1619.00±206.03 units/L) and chronically immobilized Aloe vera extract (1448.00±106.07 units/L). Conclusion: This study showed that gavage of Aloe vera extract (600mg/kg/daily) in rats can prevent the elevation of creatine kinase enzyme activity resulted by immobilization stress.

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Background and Objective: Aloe vera (Aloe barbadensis M.) as a medicinal herb is practiced in wound healing. This study was carried out to assess the effect of Aloe vera gel (mucilage) on TGF-β gene expression in incisional skin wound in BALB/c mice. Method: In this experimental study, 36 BALB/c male mice with weight range 22±2 gr were allocated equally into negative control (no wound), sham-operated (wound treated with physiological serum) and teratment (wound treated with Aloe vera gel). Two equal full-thickness skin wounds of 10±2mm were made on either side of the vertebral column in the sacral region. The animals in the teratment group were received daily, 2 gram of Aloe vera gel (without any bandage) as a thin layer for a period of 16 days. On 8th and 16th post wounding day, TGF-β gene expression in incisional wounds and Malonyldialdehyde (as end-product of lipid peroxidation) in serum samples was measured using RT-PCR and spectrophotometry methods, respectively. Results: TGF-β gene expression in incisional skin wound increased in Aloe vera gel treated group in compared to negative control and sham-operated groups (P<0.05). Malonyldialdehyde concentration was significantly reduced in Aloe vera treated group in comparision with negative control and sham-operated groups. Conclusion: Aloe vera gel can induce growth factor TGF-β gene expression and reducing the lipid peroxidation content can play an important role in incisional skin wound healing process.

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Background and Objective: Aloe Vera is considered as one of herbs causes oxidative indexes modification due to antioxidant properties. On the other hands, High-fat diets (HFD) cause liver disorders prevalence. This study was done to evaluate the protective effect of hydro-alcoholic extract of Aloe Vera gel on enzymes and liver tissue structure of high-fat diet rats.
Methods: In this experimental study, 40 adult male rats were allocated in five groups including control, sham (HFD 10 ml/kg) and three experimental groups receiving HFD with doses of 150, 300 and 600 mg/kg/bw of Aloe Vera gel extract. Prescriptions were conducted by gavage and for 60 days. Blood samples were collected to measure AST, ALT and ALP enzymes. Liver removed subsequently and following preparing tissue sections liver cells were counted.
Results: High-fat diet significantly increased ALP and ALT enzymes (P<0.05). High-fat diet significantly increased the number of Kupffer cells and reduced of hepatocytes in compared to control group (P<0.05). High-fat diet caused liver tissue alterations including blood congestion, inflmation; Vacuole breakdown, apoptosis, and ballooning of hepatocytes. On the other hand, the consumption of Aloe Vera with high-fat diet caused reduction in tissue changes and a significant decrease in the serum levels of ALP and ALT enzymes in compared to control group (P<0.05).
Conclusion: High-fat diet by damaging the liver tissue  increased  the serum levels of ALP and ALT enzymes and Aloe Vera extract with its anti-oxidant characteristic prevent the effect of a high-fat diet on the liver tissue and reduced the ALP and ALT enzymes.