An Aniline-Substituted Bile Salt Analog Protects Both Mice and Hamsters From Multiple Clostridioides Difficile Strains

Authors

Jacqueline R. Phan, University of Nevada, Las VegasFollow
Dung M. Do, University of Nevada, Las Vegas
Minh Chau Truong, University of Nevada, Las Vegas
Connie Ngo, University of Nevada, Las Vegas
Julian H. Phan, University of Nevada, Las Vegas
Shiv K. Sharma, Wayne State University
Angel Schilke, Wayne State University
Chrisabelle C. Mefferd, University of Nevada, Las Vegas
Jacob V. Villarama, University of Nevada, Las Vegas
Dengxun Lai, University of Nevada, Las Vegas
Amber Consul, University of Nevada, Las Vegas
Brian P. Hedlund, University of Nevada, Las VegasFollow
Steven M. Firestine, Wayne State University
Ernesto Abel-Santos, University of Nevada, Las VegasFollow

Document Type

Article

Publication Date

1-1-2022

Publication Title

Antimicrobial Agents and Chemotherapy

Volume

66

Issue

1

Abstract

Clostridioides difficile infection (CDI) is the major identifiable cause of antibiotic- associated diarrhea. The emergence of hypervirulent C. difficile strains has led to increases in both hospital- and community-acquired CDI. Furthermore, the rate of CDI relapse from hypervirulent strains can reach up to 25%. Thus, standard treatments are rendered less effective, making new methods of prevention and treatment more critical. Previously, the bile salt analog CamSA (cholic acid substituted with maminosulfonic acid) was shown to inhibit spore germination in vitro and protect mice and hamsters from C. difficile strain 630. Here, we show that CamSA was less active in preventing spore germination by other C. difficile ribotypes, including the hypervirulent strain R20291. The strain-specific in vitro germination activity of CamSA correlated with its ability to prevent CDI in mice. Additional bile salt analogs were screened for in vitro germination inhibition activity against strain R20291, and the most active compounds were tested against other strains. An aniline-substituted bile salt analog, CaPA (cholic acid substituted with phenylamine), was found to be a better antigerminant than CamSA against eight different C. difficile strains. In addition, CaPA was capable of reducing, delaying, or preventing murine CDI signs with all strains tested. CaPA-treated mice showed no obvious toxicity and showed minor effects on their gut microbiome. CaPA's efficacy was further confirmed by its ability to prevent CDI in hamsters infected with strain 630. These data suggest that C. difficile spores respond to germination inhibitors in a strain-dependent manner. However, careful screening can identify antigerminants with broad CDI prophylaxis activity.

Keywords

Antibiotic-associated diarrhea; Bacterial spores; Bile salts; Clostridioides difficile; Prophylaxis; Spore germination

Disciplines

Cell Biology | Immunology of Infectious Disease

Repository Citation

Phan, J. R., Do, D. M., Truong, M., Ngo, C., Phan, J. H., Sharma, S., Schilke, A., Mefferd, C. C., Villarama, J. V., Lai, D., Consul, A., Hedlund, B. P., Firestine, S., Abel-Santos, E. (2022). An Aniline-Substituted Bile Salt Analog Protects Both Mice and Hamsters From Multiple Clostridioides Difficile Strains. Antimicrobial Agents and Chemotherapy, 66(1),
http://dx.doi.org/10.1128/AAC.01435-21