hUCMSC Exosomes and Cardiac Aging in Mice: AMPKα2-Linked Kbhb Changes
In aged mice, human umbilical cord mesenchymal stromal cell-derived exosomes improved heart function in wild-type animals but only partly in AMPKα2-knockout animals, alongside changes in lysine β-hydroxybutyrylation (Kbhb) on cardiac proteins. [1]
Automatic summary · not editorially reviewed
The key findings
In aged wild-type mice, exosomes improved systolic and diastolic function, grip strength, fibrosis and ATP levels. [1]
In aged mice lacking AMPKα2, exosomes partly improved mitochondrial structure and diastolic measures but did not rescue systolic function or fibrosis. [1]
Modeling suggested K141bhb may destabilize the α-helical structure and act as a metabolic brake on CRAT. [1]
The source at a glance
- Study type / format
- Preclinical mouse study with quantitative proteomics and molecular modeling (abstract).
- Population / context
- Aged wild-type and AMPKα2-knockout mice, with young and aged untreated controls.
- Summary based on
- Study abstract
- Original publication
- October 15, 2026
Aged wild-type and AMPKα2-knockout mice given exosomes
The study asked whether the cardiac Kbhb landscape can be reversed therapeutically. The authors gave exosomes from human umbilical cord mesenchymal stromal cells to aged wild-type mice and to aged mice lacking AMPKα2. Young and aged untreated mice served as controls. Across six groups, they mapped 1,755 Kbhb sites on 652 proteins. In aged wild-type mice, exosomes improved systolic and diastolic function, increased grip strength, reduced fibrosis and restored ATP levels.
Supporting source [1]
Partial effects in mice lacking AMPKα2
In aged mice lacking AMPKα2, exosomes only partly improved mitochondrial structure and diastolic measures; systolic function and fibrosis were not rescued. Site-level analysis found that exosomes selectively normalized Kbhb sites that rise with aging, whereas AMPKα2 deficiency caused a nonselective global depletion. The authors propose a candidate AMPKα2-SIRT3 pathway, supported by SIRT5, as a possible basis. They validated CRAT K141bhb as an age-accumulated modification reversed by exosomes in an AMPKα2-associated manner.
Supporting source [1]
Modeling suggests K141bhb may brake CRAT
Molecular modeling indicated that K141bhb neutralizes the positive charge of K141, disrupting a local salt bridge between K141 and E144 and destabilizing the α-helical structure. The authors suggest this may act as a metabolic brake on CRAT activity. These are mouse and modeling findings; the abstract does not report human outcomes, and the proposed pathway is a candidate rather than an established mechanism.
Supporting source [1]
How to interpret this
Abstract only; the full text was not reviewed. Findings come from aged mice and molecular modeling, not human outcomes. The AMPKα2-SIRT3 pathway is a candidate, and the CRAT brake idea is suggested, not established.
Based on the study abstract; the full paper, tables and supplementary data were not reviewed.
Source & supporting passages
Li X, Ding W, Yang X, Tang C, Yu W, Jia X, Zhang Z, Song Y, Ling M, Yao G, Xing Y. · europepmc.org · October 15, 2026