Mitochondrial STING rewires metabolism in diabetic cardiomyopathy
For years, STING has been viewed primarily as an innate immune sensor. This new Circulation Research study argues that STING also acts as a mitochondrial metabolic regulator, directly coupling mitochondrial dysfunction to glycolytic reprogramming in diabetic cardiomyopathy (DCM).
Hyperlipidemia-induced mitochondrial DNA leakage activates cGAS–STING, but activated STING doesn't simply trigger TBK1–IRF3 signaling.
Instead, it translocates to the mitochondrial outer membrane, where it:
• Binds TOM40, impairing mitochondrial protein import.
• Recruits ENO1, increasing glycolytic flux.
• Drives pyruvate/lactate accumulation.
• Promotes mitochondrial dysfunction and contractile failure.
The authors identify a previously unrecognized TOM40–STING–ENO1 immunometabolic complex that spatially links mitochondrial injury with metabolic rewiring.
Even more interesting is the regulatory mechanism.
In diabetes, endogenous H₂S declines, reducing STING S-sulfhydration (Cys88/91). This favors STING S-palmitoylation, enhancing mitochondrial localization. Restoring H₂S using GYY4137 reverses this switch, decreases mitochondrial STING accumulation, restores oxidative phosphorylation, suppresses glycolysis, and improves cardiac function in two diabetic mouse models.
Why this matters
This work substantially expands STING biology beyond canonical innate immunity.
Instead of acting solely as an inflammatory adaptor, mitochondrial STING functions as an immunometabolic scaffold that integrates:
→ mitochondrial protein import
→ glycolytic enzyme regulation
→ metabolic remodeling
→ cardiac dysfunction
The findings also introduce post-translational modification switching (S-palmitoylation ↔ S-sulfhydration) as a mechanism controlling STING subcellular localization.
Remaining questions
• Does the TOM40–STING–ENO1 complex exist in human cardiomyocytes?
• Is mitochondrial STING involved in HFpEF, obesity, MASLD, or aging hearts?
• Could mitochondrial-localized STING explain metabolic remodeling in non-diabetic heart failure?
• Can selective modulation of STING localization outperform global STING inhibition?
This study opens an intriguing direction where subcellular localization—not simply pathway activation—determines STING function.
Title: Mitochondrial STING Governs Glycolytic Reprogramming in Diabetic Cardiomyopathy
Journal: Circulation Research (2026)
DOI: 10.1161/CIRCRESAHA.125.327867
Aging-associated inflammation ("inflammaging") is a major driver of tissue dysfunction, frailty, and chronic disease. But what if a previously overlooked nucleic acid structure is helping fuel it?
A new study in Nature Aging identifies a mechanistic link between R-loops, cellular senescence, and inflammaging.
Key findings:
🔹 Senescent cells accumulate cytoplasmic R-loops derived from the nucleus.
🔹 These R-loops localize to cytoplasmic chromatin fragments (CCFs) and activate the cGAS–STING innate immune pathway, driving the senescence-associated secretory phenotype (SASP).
🔹 The study identifies a previously unrecognized transport mechanism:
Nuclear R-loop → DDX1 → XPO1 export → CCF localization → cGAS activation → SASP → inflammaging
DDX1 acts as an R-loop-binding export adaptor, while XPO1 mediates nuclear export.
🔹 Cytoplasmic R-loops were enriched for alpha-satellite repeat sequences, linking centromeric instability and repetitive-element biology to age-associated inflammation.
🔹 Pharmacologic inhibition of XPO1 using KPT-330 (selinexor):
• Reduced cytoplasmic R-loops
• Suppressed cGAS-STING signaling
• Lowered SASP factors
• Reduced liver inflammation and fibrosis
• Decreased circulating TNF and IL-6
• Improved body composition
• Extended lifespan in aged mice
Conceptually, this work introduces R-loop trafficking as a new aging mechanism.
Rather than acting solely as nuclear genome-instability intermediates, R-loops can become exported inflammatory signals that couple DNA damage responses to innate immunity.
The study positions the:
DDX1–XPO1–R-loop–cGAS axis
as a potentially druggable pathway for suppressing inflammaging and age-related functional decline.
Nature Aging (2026)
Hao et al.
Nuclear export of R-loop by the DDX1 and XPO1 complex promotes senescence-associated secretory phenotype and inflammaging
#Aging #Inflammaging #Senescence #SASP #RLoops #cGAS #STING #DDX1 #XPO1 #Selinexor #Longevity #NatureAging
THIS IS THE BEST PAPER OF 2026 SO FAR, A MONUMENTAL BREAKTHROUGH, A REVOLUTION IN THE FIELD OF INFLAMMATORY CONDITIONS:
Interleukin-10 Autoantibodies and HLA-DRB1*01:03 in Inflammatory Bowel Disease | New England Journal of Medicine https://t.co/4fKMgPMd4y