**6. Conclusions**

SCFAs produced by microbial fermentation have been widely shown to reduce inflammation and oxidative stress, which are characteristic of several chronic diseases. CKD is a serious health problem, not least because of the systemic complications associated with it, and it is also a chronic condition that is very difficult to manage because of the underlying disease mechanisms. Therefore, the supplementation of short-chain fatty acids (e.g., acetate, propionate, or butyrate), either directly or by modulating the gut microbiota in favour of SCFA-producing bacterial species, including through dietary fibre or nutritional thera-

pies, could have a positive impact on the management of chronic renal failure (Figure 3). However, further studies are still needed.

**Figure 3.** SCFAs result in increased activity on G-protein-coupled receptors and enhanced epigenetic regulatory activity through HDAC. SCFAs could be able to act positively on pro-inflammatory pathways (e.g., by negatively modulating the NF-κB signalling pathway) and pro-oxidant pathways (e.g., by positively modulating the Nrf2 pathway).

**Author Contributions:** S.M., B.R.D.I. and A.H. conceived the work; G.M. and S.M. wrote the manuscript; P.M., B.R.D.I. and A.H. edited the manuscript. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was founded by University of Salerno (FARB 2021- ORSA210342) granted to S.M.

**Conflicts of Interest:** The authors declare no conflict of interest.
