Herbal Formula Counteracts Immune Stress in Simulated Microgravity

A three-herb preparation restored immune function in rats living under simulated weightlessness and then challenged with bacteria, a research team in China reports. The study, published in Model Organisms Research, points to a nutritional way of helping crews stay well on long missions, and possibly to similar support for people on the ground.

Long-duration flight weakens the immune system, and space crew in orbit also face infection risk from microorganisms that behave differently. Escherichia coli is a normal gut bacterium, and on the ground it rarely causes trouble. In low-gravity experiments, however, bacteria including E. coli have been reported to form tougher biofilms and to switch on genes linked to virulence. Weightlessness weakens the host's own defences at the same time, and in orbit the two effects arrive together.

Jing Liu and Yao Xie of Beijing Dongfanghong Aerospace Biotech Co. Ltd., working with researchers at Beijing Institute of Technology, built a "two-hit" model to reproduce that combination: rats were tail-suspended for four weeks to simulate microgravity and given E. coli by intragastric gavage, while receiving the Ganoderma-Rhodiola Compound Preparation (GRCP), made from Ganoderma lucidum, Rhodiola rosea and Paecilomyces hepiali mycelium, daily. While most studies use one, this study combines two stressors.

Compared with untreated animals, those given GRCP showed a broadly restored immune profile across immune organs, immune cells and signalling factors. Inflammation fell both in the blood and in the lining of the gut, and the internal structure of the spleen held up. NF-κB/RelA, a switch that drives inflammation, was held in check, which the team identifies as the likely route by which a single preparation produces multi-target immune regulation. The effect was clearest at the highest dose tested.

“Traditional Chinese medicine brings a multi-component, multi-target advantage to protecting against stress-induced injury,” explains corresponding author Professor Yu-Lin Deng, School of Medical Technology, Beijing Institute of Technology, Beijing, China. “What we designed for the demands of spaceflight rests on a mechanism that is not specific to space — an innovation born for space that may end up helping far more people on the ground.” 

The results provide a scientific basis for testing GRCP as a way of protecting crew health on long-duration crewed missions. The same decline in immune function seen in space also affects long-term bedridden patients, older adults and people who sit all day.

Contact the author:

Yu-Lin Deng, School of Medical Technology, Beijing Institute of Technology, Beijing, China, deng@bit.edu.cn.

Funder:

This research was supported by internal research funding. No external funding sources were involved.

Conflict of interest:

The authors declare that there are no conflicts of interest in this work.

See the article:

Jing L., et al., Suppression of NF-κB signaling by Ganoderma-Rhodiola compound preparation alleviates immune dysregulation in a rat model of simulated microgravity, Model Organisms Research, Volume 1, Issue 2, 2026, Pages 100022, https://doi.org/10.1016/j.mores.2026.100022.