The pandanus tectorius fruit extract (PTF) modulates the gut microbiota and exerts anti-hyperlipidaemic effects

Background: The gut microbiota plays a key role in the maintenance of human health and mediates the beneficial effects of natural products including polyphenols. Previous studies have demonstrated that the polyphenol-rich Pandanus tectorius fruit extract (PTF) was effective in ameliorating high-fat diet (HFD)-induced hyperlipidaemia, and polyphenols can significantly change the structure of the gut microbiota. Purpose: In this study, we assessed whether the modulation of the gut microbiota plays a key role in the PTF-induced anti-hyperlipidaemic effects. Methods: Male C57BL/6 J mice were induced with hyperlipidaemia by consuming a high-fat diet (HFD) for 4 weeks. Then, the mice were orally administered PTF, antibiotics (ampicillin+norfloxacin), PTF+antibiotics or vehicle for another 6 weeks. Body weights and 24-h food intake were assessed weekly. At the end of the experiment, fresh stools were collected for 16S RNA pyrosequencing, and blood and liver and fat tissue were collected for pharmacological analysis. Results: PTF was effective in ameliorating high-fat diet (HFD)-induced hyperlipidaemia and significantly changed the structure of the gut microbiota. However, the anti-hyperlipidaemic effect of PTF was not influenced by the co-treatment with antibiotics (ampicillin+norfloxacin). A microbiological analysis of the gut microbiotas revealed that PTF selectively enhanced the relative abundance of Lactobacillus and decreased the relative abundance of Bacteroides and Alistipes. A correlation analysis between biochemical indexes and individual taxon showed that Lactobacillus was negatively associated with serum lipids and glucose while Bacteroides and Alistipes were positively associated with serum lipids and glucose. The modulatory effect of PTF on Lactobacillus, Bacteroides and Alistipes was not disturbed by the administration of antibiotics. Conclusion: These results demonstrated that the polyphenol-rich PTF as a unique gut microbiota modulating agent and highlighted the richness of Lactobacillus and the decreased abundance of Bacteroides and Alistipes as an effective indicator of the therapeutic effect of medicinal foods on hyperlipidaemia.