Bacterial supplementation in mitigation of radiation-induced gastrointestinal damage

Tea Polyphenols Mitigate Radiation-Induced Ferroptosis and Intestinal Injury by Targeting the Nrf2/HO-1/GPX4 Signaling Pathway

Radiation-induced intestinal injury (RIII) is a significant concern for cancer patients receiving radiation therapy, as it can lead to complications such as radiation enteropathy. Presently, there are limited options for preventing or treating RIII. Tea polyphenols (TP), found in tea, provide various health benefits, but their antiradiation mechanisms are not fully understood. C57BL/6 mice pre-treated with TP for five days showed a significant improvement in survival rates after being exposed to 10 Gy of 60Co radiation. In the same way, abdominal exposure to 15 Gy of 60Co radiation effectively mitigated radiation-induced colon shortening, damage to intestinal tissues, oxidative stress, the release of inflammatory factors, and disruptions in intestinal microbial balance. In addition, TP treatment lowered the elevation of reactive oxygen species (ROS), iron imbalance, mitochondrial damage, and ferroptosis in IEC-6 cells post-irradiation. Utilizing network pharmacology, molecular docking, and affinity testing, we identified that TP has the capability to target the Nrf2/HO-1/GPX4 signaling pathway, while EGCG, a principal constituent of TP, interacts with HSP90 and mitigates radiation-induced ferroptosis. These findings suggest that TP may serve as a promising therapeutic agent to alleviate radiation-induced intestinal injury (RII).

The gut microbiome and cancer: from tumorigenesis to therapy

The gut microbiome has a crucial role in cancer development and therapy through its interactions with the immune system and tumour microenvironment. Although evidence links gut microbiota composition to cancer progression, its precise role in modulating treatment responses remains unclear. In this Review, we summarize current knowledge on the gut microbiome's involvement in cancer, covering its role in tumour initiation and progression, interactions with chemotherapy, radiotherapy and targeted therapies, and its influence on cancer immunotherapy. We discuss the impact of microbial metabolites on immune responses, the relationship between specific bacterial species and treatment outcomes, and potential microbiota-based therapeutic strategies, including dietary interventions, probiotics and faecal microbiota transplantation. Understanding these complex microbiota-immune interactions is critical for optimizing cancer therapies. Future research should focus on defining microbial signatures associated with treatment success and developing targeted microbiome modulation strategies to enhance patient outcomes.

Maintained homeostasis: LGYD facilitated the restoration of ISCs following radiation exposure by activating Hes1

BACKGROUND

Radiation-induced Intestinal Injury (RIII) affects quality of life in radiotherapy patients; Liangxue Guyuan Yishen Decoction (LGYD) offers protection but requires further study on its mechanism.

PURPOSE

The aim of this study was to investigate the heterogeneity of cellular responses in the intestine at a single-cell level following radiation and LGYD treatment.

STUDY DESIGN

This study's design includes in vivo and in vitro assessments to evaluate LGYD's effects on intestinal cells post-radiation, targeting survival, recovery, and molecular pathways.

METHODS

Mice were categorized into four groups: LGYD group, NC group, IR group, and Am group. Each group received daily drug administrations. All groups, except for the NC group, were subjected to a single whole-body irradiation at a dose rate of 70 R/min with a source-to-skin distance of 250 cm. Subsequent experiments were conducted following the irradiation, which led to severe survival impairments in the mice.

RESULTS

Our findings demonstrate that LGYD intervention substantially improves survival rates following lethal doses (8.5 Gy, 70R/min) of whole-body irradiation. Moreover, LGYD expedites the recovery period for intestinal injury on the fifth day after radiation by promoting repair mechanisms within intestinal tissue, with particular focus on mitigating intestinal stem cells (ISCs) damage and immune disorders. Through both in vivo and in vitro experiments, we have discovered that LGYD effectively treats RIII by activating Hes1 transcription factor activity through its key active ingredients in drug-containing serum. This activation further upregulates the downstream Stat3 and Akt gene, thereby facilitating repair processes within intestinal stem cells.

CONCLUSION

In this study, we discovered that LGYD can enhance the downstream expression and phosphorylation pathways of Stat3 and Akt by upregulating the expression of Hes1 gene following high-dose radiation exposure.