The low-molecular-weight fraction (T3) of ripe Pu-erh tea protects against alcohol-induced gastric injury through a gut microbiota-dependent mechanism involving enrichment of Dubosiella and Bifidobacterium, increased butyrate production, and modulation of glutathione-related pathways.
Key Findings
Results
The low-molecular-weight fraction T3 (<300 kDa) of ripe Pu-erh tea exhibited the strongest gastroprotective activity among three membrane-separated fractions in mouse models of acute alcoholic gastric injury.
Ripe Pu-erh tea extract was fractionated into three fractions (T1-T3) using membrane separation, with T3 obtained using a 50 nm ceramic membrane
T3 was evaluated in both preventive and therapeutic mouse models of acute alcoholic gastric injury (AGI)
T3 demonstrated stronger gastroprotective activity compared to higher-molecular-weight fractions T1 and T2
Preventive efficacy of T3 exceeded its therapeutic efficacy, highlighting the value of early intervention
Results
Preventive T3 administration alleviated gastric mucosal injury and restored prostaglandin E2 (PGE2) levels in alcohol-challenged mice.
T3 was administered preventively prior to alcohol challenge in the mouse model
Gastric mucosal injury was assessed histologically and showed attenuation with T3 pretreatment
PGE2 levels, which are involved in gastric mucosal protection, were restored following T3 administration
These effects were observed alongside attenuation of inflammation and oxidative stress
Results
T3 treatment attenuated alcohol-induced inflammation and oxidative stress in the gastric mucosa.
Inflammatory markers were reduced following preventive T3 administration
Oxidative stress parameters were attenuated by T3 treatment
These protective effects were part of a broader modulation of microbiota-gut-stomach homeostasis
Results
T3 administration improved intestinal barrier function in alcohol-challenged mice.
Intestinal barrier function was assessed as part of the gut-stomach axis evaluation
Improvement in intestinal barrier integrity was observed with preventive T3 treatment
Intestinal barrier restoration occurred alongside gut microbiota remodeling
These findings support a microbiota-gut-stomach homeostasis mechanism of protection
Results
T3 administration remodeled gut microbiota composition, including enrichment of Dubosiella and Bifidobacterium and increased butyrate production.
Gut microbiota remodeling was identified as a key mechanism of T3's gastroprotective effects
Specific enrichment of Dubosiella and Bifidobacterium genera was observed following T3 treatment
Increased production of butyrate, a beneficial short-chain fatty acid, accompanied the microbiota changes
These microbiota changes occurred in parallel with improvements in gastric mucosal protection and reduced inflammation
Results
Antibiotic-mediated gut microbiota depletion attenuated T3 efficacy, supporting a microbiota-dependent mechanism of gastroprotection.
An antibiotic treatment protocol was used to deplete gut microbiota in mice
Following microbiota depletion, the gastroprotective effects of T3 were attenuated
This finding directly supports a gut microbiota-dependent mechanism for T3's protective activity
The result indicates that an intact gut microbiome is necessary for the full gastroprotective effect of T3
Results
Serum metabolomics analysis indicated that T3 treatment regulated glutathione-related metabolic pathways.
Serum metabolomics was employed to identify systemic metabolic changes associated with T3 treatment
Glutathione-related pathways were among the significantly modulated pathways identified
Glutathione pathway regulation is consistent with the observed attenuation of oxidative stress
Metabolomics data complemented the microbiota findings to provide a mechanistic understanding of T3's effects
What This Means
This research suggests that a specific low-molecular-weight component of ripe Pu-erh tea (a fermented Chinese tea) can protect the stomach lining from damage caused by alcohol consumption. The researchers separated Pu-erh tea extract into three size-based fractions and tested them in mice given alcohol to induce stomach injury. The smallest fraction, called T3, was the most effective at preventing stomach damage, and it worked better when given before alcohol exposure rather than after, suggesting it is more useful as a preventive measure than a treatment.
The study found that T3 works through multiple interconnected pathways. It reduced inflammation and oxidative stress in the stomach, restored protective compounds in the stomach lining, and improved the integrity of the intestinal barrier. Importantly, T3 also changed the composition of the gut microbiome — the community of bacteria living in the intestines — by increasing beneficial bacteria called Dubosiella and Bifidobacterium and boosting production of butyrate, a beneficial compound made by gut bacteria. When researchers used antibiotics to wipe out the gut bacteria, T3 lost much of its protective effect, proving that the gut microbiome plays a critical role in how T3 works.
This research suggests that components of ripe Pu-erh tea, particularly its low-molecular-weight fraction, could potentially be developed as a dietary strategy to help protect against stomach damage from alcohol consumption by working through the gut-stomach axis. The findings highlight the importance of the gut microbiome as a mediator of dietary compounds' health effects, and point to butyrate production and glutathione-related antioxidant pathways as key mechanisms. Further research in humans would be needed to confirm these effects.
Zhao S, Jiang J, Xu M, Liu Y, Dai L, Guan X, et al.. (2026). Low-Molecular-Weight Fraction of Ripe Pu-erh Tea Protects against Alcohol-Induced Gastric Injury via Gut Microbiota-Dependent Modulation.. Journal of agricultural and food chemistry. https://doi.org/10.1021/acs.jafc.6c01237