Serum CA19-9 and CEA levels, Serum CAT, GSH, oxidized glutathione levels , 8-dihidro-2′-deoxiguanosina and F2-Isoprostanes levels in colorectal cancer patients with Lactobacillus: A randomized double-blind controlled trial
Abstract
Background: Oxidative stress (OS) plays a crucial role in colorectal cancer (CRC) progression. Lactobacillus has been proposed as a potential modulator of OS. This randomized controlled trial aimed to evaluate the effects of Lactobacillus supplementation on OS markers and its related signaling pathways in CRC patients after surgery.
Methods: A total of 76 CRC patients were enrolled and randomized into two groups: the study group (n=39) received Lactobacillus supplementation, while the control group (n=37) received a placebo. The intervention lasted for six months following surgery. Serum levels of catalase (CAT), glutathione (GSH), oxidized glutathione (GSSG), 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG), and F2-isoprostanes (F2-IsoPs) were measured. In addition, the NRF2/KEAP1, p38 MAPK, and JNK signaling pathways were assessed via western blot analysis.
Results: Following Lactobacillus supplementation, serum CEA levels significantly decreased, whereas CA19-9 levels remained unchanged. OS marker analysis demonstrated increased CAT, GSH, and F2-IsoPs levels and decreased GSSG and 8-oxodG levels in the study group compared to the control group. Western blot results revealed that NRF2, ASK1, MKK3, p-p38, and MKK4 protein levels were significantly reduced after Lactobacillus intervention, while KEAP1 and p-JNK remained unchanged.
Conclusions: Oral administration of Lactobacillus for six months reduced OS marker levels and inhibited NRF2/KEAP1, p38 MAPK, and JNK signaling pathways in CRC patients after surgery. These findings suggest that Lactobacillus may contribute to CRC management by modulating oxidative stress.
Copyright (c) 2025 Shiru Chen, Weili Ning, Jiye Zhang, Zhenting Wu, Hang Zhou, Ying Liu

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