EVALUATION OF PROTECTIVE EFFECTS OF SPIRULINA PLATENSIS AGAINST AFLATOXIN B1 INDUCED TOXICITIES IN SWISS ALBINO MICE

Abstract

Aflatoxins are toxic metabolites produced by Aspergillus species principally by Aspergillus flavus and Aspergillus parasiticus. Aflatoxins are teratogenic, mutagenic, carcinogenic, immunosuppressive and have been associated with various diseases conditions. Chemoprotective strategies are required to reduce both exposure to and the adverse health effects of aflatoxins, hence the basis for the present study. The main objective of this study was evaluation of protective effects of Spirulina platensis (SP) extract against aflatoxin B1 (AFB1) induced toxicities in male Swiss albino mice. These were evaluated by biochemical changes, histopathological changes, immune changes and probable mechanism of action. Randomly, 25 male Swiss albino mice were allocated into 5 groups. Group I (Control group); mice received normal diet. Group II mice received SP 100 mg/kg/day. Group III mice received 200 µg/kg/day of AFB1. Group IV mice received 200 µg/kg/day of AFB1 and SP 100 mg/kg/day. Group V mice received 200 µg/kg/day of AFB1 and SP 100 mg/kg/day. The treatments were administered orally for 28 days. One-way ANOVA statistical test was used to compare group means. Data was statistically significant if (P<0.05). If statistically significant differences were found (P<0.05), post-hoc comparisons between multiple groups were done using Tukey’s Honestly Significantly Differenced (HSD). Python® 3.0 with statistical libraries data analysis software was used. Results showed that compared to group I (control), group III (200 µg/Kg/day AFB1) had increased levels of alanine aminotransaminase (ALT); (44.0±6.83 IU/L vs. 61.0±8.19 IU/L; p=0.054) and aspartate aminotransferase (AST (176.75±44.34 IU/L vs. 256±115.99 IU/L; p=0.0195). Mice that were co-treated with 200 µg/Kg/day of AFB1 and 200 mg/Kg/day of SP extract exhibited lower levels compared to mice treated with only 200 mg/Kg/day of AFB1; ALT (49.8±7.9 IU/L vs. 61.5±8.19 IU/L; p=0.039) and AST (229.8±95 IU/L vs. 256±11.15 IU/L; p=0.04819). These findings were furthered by histology photomicrographs of liver and kidney tissues samples. With regard to the immune changes, comparison of group I (control) with group III; IgA reduced (AFB1 200 µg/Kg/day) (0.7147 ± 0.001 vs. 0.7075 ± 0.010); IgM levels were also reduced (0.0916 ± 0.003 vs. 0.0866 ± 0.019); IgG levels were elevated (0.1746 ± 0.001 vs. 0.2808 ± 0.243). Administration of AFB1 200 µg/Kg/day followed by supplementation of S. platensis extract 200 mg/Kg/day as seen in group V compared to group III (AFB1 200 µg/Kg/day) reversed depression of IgA levels (0.7124 ± 0.005 vs. 0.7075 ± 0.010; P=0.05437); IgM (0.1005 ± 0.004 vs. 0.0866 ± 0.019; P=0.0178); IgG levels were reduced (0.1749±0.001 vs. 0.2808± 0.243; P=0.0155). In regard to MDA equivalents, co-administration of (AFB1 200 µg/Kg/day + SP 100 mg/Kg/day) reduced the the mean concentration of MDA equivalents (µmol) in the liver and kidney compared to group III (AFB1 200 µg/Kg/day). Also, co-administration of (AFB1 200 µg/Kg/day + SP 200 mg/Kg/day) further reduced the the mean concentration of MDA equivalents (µmol) in the liver and kidney compared to group III (AFB1 200 µg/Kg/day). In conclusion, co-treatment of S. platensis extract in doses ranging from 100 mg/Kg/day to 200 mg/Kg/day inhibits biochemical changes, immune changes, histopathological changes in liver and kidney and it lowers MDA equivalent concentration caused by 200 µg/Kg/day of AFB1 in male Swiss albino mice. This study recommends clinical trials on Spirulina platensis to evaluate its protective effect against aflatoxin induced toxicity in human beings.