COG 133 is a fragment of Apolipoprotein E (APOE) peptide with potent anti-inflammatory and neuroprotective effects. COG 133 is also a nAChR antagonist with an IC50 of 445 nM. COG 133 (0.02, 0.2, and 2.0 μM) improved cell numbers in glutamine free media. In IEC-6 cells, COG 133 (0.2-20 μM) improved cell migration following 5-FU challenge, reaching the same migration level as controls. COG 133 (3 μM) significantly increased the mitotic crypt numbers in C57BL6J wild-type animals. COG 133 treatment improved crypt architecture and reduced lamina propria inflammation. COG 133 (3 μM) significantly reduced the intestinal MPO levels. COG 133 partially decreased TNF-α level in the proximal small intestine from 5-FU-treated mice. In both wild-type and ApoE knock-out mice, COG 133 (3 μM) reverted the increase in Tunel-positive cells in the proximal intestine induced by 5-FU. COG 133 caused higher expression of the NF-κB in the improved intestinal mucosa.