IDDF2021-ABS-0201 Study on the promotion of lipopolysaccharide from shewanella algae on the occurrence and development of colorectal adenoma
Year: 2021
Type: conference-paper
Abstract: Background Colorectal adenoma (CRA) is a recognized precancerous lesion of colorectal cancer (CRC). Intestinal flora is closely related to many diseases, including CRA and CRC. Our previous study found that the abundance of Shewanella algae (S.algae) was significantly increased in CRA patients. Next, it was found that S.algae can significantly promote the development of CRA in APCmin/+ mice, and the levels of macrophages and lipopolysaccharide (LPS) were increased after using S.algae to gavage APCmin/+ mice. The bioactivity of LPS from different bacteria is different. Escherichia coli (E.coli) LPS has been shown to promote the development of tumors, while the bioactivity of S.algae LPS to CRA is not yet clear. Methods Twenty-four female C57BL/6J mice were randomly divided into the Control group, the AOM/DSS group, the AOM/DSS+LPS group, and the AOM/DSS+S.algae group, with 6 mice in each group. The mice in the three experimental groups were given an intraperitoneal injection of AOM 10mg/kg, while the Control group was injected with the same amount of normal saline. After a week, the mice in the three experimental groups were regrouped according to body weight and given 2.5% DSS solution for 5 days and normal drinking water for 14 days. The mice were weighed every 3 days and killed at the end of the experiment on the 26th day. S.algae and its LPS were administered began on the eighth day and was gavaged every two days until the end of the experiment, while the Control group were given an equal amount of PBS by gavage. Results Compared with the AOM/DSS group, mice in the AOM/DSS+LPS group and the AOM/DSS+S.algae group developed more intestinal polyps (IDDF2021-ABS-0201 Figure 1. Body mass, colorectal length, and polyps of mice in each group) and more severe atypical hyperplasia (IDDF2021-ABS-0201 Figure 2. The pathological changes of the colorectum in mice of each group). M1 macrophages (CD11b+/CD86+) (IDDF2021-ABS-0201 Figure 3. The protein and mRNA levels of CD11b, CD86, CD163 in adenoma tissue of each group), proliferation and periodic proteins (Ki67, PCNA, Cyclin D1) (IDDF2021-ABS-0205 Figure 4.The protein levels of Ki-67, PCNA, and Cyclin D1 in adenoma tissue of each group) and various pro-inflammatory factors (IDDF2021-ABS-0201 Figure 5. The expression of protein and mRNA of inflammatory factors in adenoma tissue of each group) were elevated, and TLR4/NF-κB pathway (IDDF2021-ABS-0201 Figure 6. The expression of TLR4/NF-κB pathway proteins in adenomas tissue of mice in each group) was activated after using S.algae and its LPS to gavage mice. Conclusions S.algae LPS may promote the occurrence and development of CRA in mice through M1 macrophages. S.algae LPS may promote the occurrence and development of CRA in mice through TLR4/NF-κB pathway.
Source: Gut
Authors: Junxiao Zhou, Junyan Li, Kaijie Liu, Yanxiao Liang, Hong Wang
Language: English
Topic: Gut microbiota and health
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W3197351612