Objective:

2

To investigate whether astragalus polysaccharides (APS) combined with berberine (BBR) can reduce high-fat diet (HFD)-induced obesity in mice.

Methods:

2

Except for normal mice

32 HFD-induced obese mice were randomized into HFD

APS (1

000 mg/kg APS)

BBR (200 mg/kg BBR)

and APS plus BBR (1

000 mg/kg APS plus 200 mg/kg BBR) groups

respectively. After 6-week treatment (once daily by gavage)

the obesity phenotype and pharmacodynamic effects were evaluated by histopathological examination of epididymal fat

liver

and colon using hematoxylin-eosin staining and serum biochemical analyses by an automated chemistry analyzer. The feces were collected at the 12 th week

and taxonomic and functional profiles of gut microbiota were analyzed by 16S ribosomal ribonucleic acid (16S rRNA) sequencing.

Results:

2

Compared with HFD group

the average body weight of APS plus BBR group was decreased (

P

<

0.01)

accompanied with the reduced fat accumulation

enhanced colonic integrity

insulin sensitivity and glucose homeostasis (

P

<

0.05 or

P

<

0.01). Importantly

APS combined with BBR treatment was more effective than APS or BBR alone in improving HFD-induced insulin resistance (

P

<

0.05 or

P

<

0.01). 16S rRNA sequence-based analysis of fecal samples demonstrated that APS combined with BBR treatment exhibited a better impact on HFD-induced gut microbiota dysbiosis

exclusively via the enriched abundances of

Bacteroides

which corresponded to the large increase of predicted bacterial genes involved in carbohydrate metabolism.

Conclusion:

2

APS combined with BBR may synergistically reduce obesity and modulate the gut microbiota in HFD-fed mice.