HDAC9 and columnar cell hyperplasia of the breast: These results indicate that CCH impaired colonic barrier function, markedly reduced the protein levels of GPR41 and GPR43, and aggravated overexpression of HDAC1/2, which were ameliorated by FMT and SCFA treatment (Fig. 4E, F), suggesting alleviation of colonic barrier dysfunction via activation of GPR41 and GPR43 and inhibition of HDAC.