OCLN and type 2 diabetes mellitus: In addition, Prevotella and Lachnospira enriched in the Hao9 group were also positively correlated with Insulin, G6Pase and PEPCK, but negatively correlated with ZO1, occludin and claudin (Figure 6), which indicated that Hao9 could only partially restore gut microbiota disturbances caused by T2DM.