Investigation of the effect of metformin and aloe vera on the reduction of pulmonary fibrosis caused by bleomycin in rat models

Background and aim: Bleomycin is an antibiotic with anti-tumor activity. The main problem with the use of this drug is the occurrence of dangerous complications of pulmonary fibrosis. The present study investigated the effect of metformin as an anti-inflammatory and anti-fibrosis and aloe vera gel with antioxidant properties and the combination of the two on the inhibition of pulmonary fibrosis due to bleomycin injection. Materials and Methods: Seven groups of adult male Wistar rats were selected with a weight range (20,200%). In addition to the control group who received a single intra-tracheal dose of 0.3 ml of sterile saline, the other groups were prescribed intra-tracheal bleomycin 1 ml per 100 g body weight in the volume of 0.3 ml. Therapeutic groups included: (1) group metformin 500 mg/kg daily, (2) aloe vera 500 mg/kg daily, (3) aloe vera 700 mg /kg daily, (4) the combined group received 500 mg/kg drug and 500 mg/kg plant simultaneously intraperitoneal as treatment in a 21-day treatment period after intra-tracheal administration of bleomycin. Data were analyzed using 22spss software to analyze the overall comparison of the completely randomized variance analysis test and Duncan's multiple range test was used to compare the groups. In all experiments, p <0.05 was considered as a significant difference. Results: The final weight of the animals during 21 days of experiments in negative control group (normal saline) was 191.55±2.13, positive control group (bleomycin) 192.85±2.63, in treatment group (1) 198.50 ±8.61, treatment group (2) 197.50 ±1.51, treatment group (3) 217.75 ±2.19, treatment group (4) 219.50±1.51 that treatment groups have shown a decrease compared to the control groups, but this decrease is not statistically significant (P< 0.05). The following results were obtained for the average lung weight of each group in grams: Negative control group (normal saline) = 1.2, positive control group (bleomycin) = 2.82, treatment group (1) = 1.62, treatment group (2) = 1.42, treatment group (3) = 1.43 and treatment group (4) is 1.25. Conclusion: According to the results, metformin, as a potent anti-fibrosis agent, which is probably due to reduced synthesis of prostaglandins, as well as aloe vera with high antioxidant effect, are able to inhibit collagen accumulation. According to the results obtained in the combined group of these two substances, a sharp decrease in the amount of collagen accumulation can be observed, which indicates its greater effect.