EFFECTS OF CAFFEINE AND NICOTINE ON THE POPULATION AND DIVERSITY OF GUT BACTERIAL MICROBIOME OF ADULT WISTAR RATS

Abstract

The study was conducted to evaluate the effect of nicotine and caffeine on the population and diversity of microbiome of the gut (large intestine) of adult Wister rats. Seventy-seven (77) adult Wistar rats weighing 150 to 200 g were randomly grouped into eleven (11) groups of seven rats each. Group 1 served as control, received water which was the vehicle (group 2 (caffeine 10 mg/kg), group 3 (caffeine 20 mg/kg), group 4 (nicotine from cigarette 170 mg/kg), group 5 (nicotine from cigarette 340 mg/kg), group 6 (nicotine from tobacco 170 mg/kg), group 7 (nicotine from tobacco 340mg/kg), group 8 (caffeine 10mg/kg and nicotine from cigarette 170 mg/kg), group 9 (caffeine 20 mg/kg and nicotine from cigarette 340 mg/kg), group 10 (caffeine 10 mg/kg and nicotine from tobacco 170 mg/kg), group 11 (caffeine 20 mg/kg and nicotine from 340 mg/kg)). The agents were administered each day, orally for 14 days. On the fifteenth day, chloroform anaesthetized animals were sacrificed after which the large intestine were harvested, homogenized and microbial populations cultured to assay for changes in population and diversity of the microbiome of the gut (large intestine). Results obtained showed significant increase in the bacteria population of animals administered caffeine 20 mg/kg, nicotine from cigarette 170 mg/kg, nicotine from cigarette 340 mg/kg, nicotine from tobacco 170mg/kg, caffeine 20mg/kg and nicotine from cigarette 340 mg/kg, caffeine 10 mg/kg and nicotine from tobacco 170 mg/kg as compared with the control. Bacillus sp. was present in all groups except the groups administered caffeine 10mg/kg and nicotine from cigarette 170mg/kg. Pseudomonas sp. was only observed in the group administered caffeine 20mg/kg. Staphylococcus sp. however was present in the control but was absent in the group administered caffeine 10mg/kg and nicotine from cigarette 170mg/kg, and the group administered caffeine 20mg/kg and nicotine from tobacco 340mg/kg. This study has shown that nicotine and caffeine consumption can alter the population and diversity of microbial species in the gut. This may likely influence the general health status of the consumer. Further studies in this regard are recommended