Max Planck Research Group Sprenger

Research

Fig. 1: Ergothioneine accumulates in muscle mitochondria upon exercise training and augments performance via MPST. (A) Comparison of ergothioneine levels in muscle mitochondria isolated from sedentary vs exercised mice. (B) Molecular modeling of the favorable binding mode of ergothioneine in the active site of MPST (PDB: 4JGT). Average running distance (km/h) of control-fed and ergothioneine-fed (C) WT and (D) Mpst-/- mice during6 consecutive light and dark cycles. Data are from Sprenger et al., bioRxiv 2024. — **Fig. 1: Ergothioneine accumulates in muscle mitochondria upon exercise training and augments performance via MPST. (A)** Comparison of ergothioneine levels in muscle mitochondria isolated from sedentary vs exercised mice. **(B)** Molecular modeling of the favorable binding mode of ergothioneine in the active site of MPST (PDB: 4JGT). Average running distance (km/h) of control-fed and ergothioneine-fed **(C)** WT and **(D)** *Mpst^-/-* mice during 6 consecutive light and dark cycles. Data are from Sprenger et al., bioRxiv 2024.

© H.-G. Sprenger

**Fig. 1: Ergothioneine accumulates in muscle mitochondria upon exercise training and augments performance via MPST. (A)** Comparison of ergothioneine levels in muscle mitochondria isolated from sedentary vs exercised mice. **(B)** Molecular modeling of the favorable binding mode of ergothioneine in the active site of MPST (PDB: 4JGT). Average running distance (km/h) of control-fed and ergothioneine-fed **(C)** WT and **(D)** *Mpst^-/-* mice during
6 consecutive light and dark cycles. Data are from Sprenger et al., bioRxiv 2024.

© H.-G. Sprenger

We recently have identified a previously unknown molecular mechanism of how skeletal muscle metabolism adapts to exercise training and promotes performance. Specifically, we found that exercise training induces accumulation of the diet-derived amino acid ergothioneine (EGT) inside muscle mitochondria. In mitochondria EGT binds and activates the enzyme 3-mercaptorpyruvate sulfurtansferase (MPST), thereby controlling mitochondrial function and enhancing exercise performance (Fig. 1, 2).

EGT is known to be present at high levels in human tissues and plasma. Reduced EGT levels have been linked to several age-related disorders, while EGT supplementation is protective in a broad range of disease models. This has led to the proposal that EGT be considered a “longevity vitamin”. Indeed, recent data suggest that EGT supplementation has significant effects on longevity and healthy ageing. However, its precise mechanisms of action during ageing and age-associated metabolic diseases are unknown.

Fig. 2: Ergothioneine and ketone body metabolism in mitochondria. Ergothioneine (EGT) is imported into mitochondria and controls mitochondrial function via direct activation of 3-mercaptopyruvate sulfurtransferase (MPST) (left panel). b-hydroxybutyrate (BHB) is imported into mitochondria and controls mitochondrial function via SCOT-dependent oxidation (right panel). 3-MP = 3-mercaptopyruvate, Pyr = pyruvate, H2S = hydrogen sulfide, ETC = electron transport chain, OXPHOS = oxidative phosphorylation. BDH1 = D-b-hydroxybutyrate dehydrogenase 1, SCOT = succinyl-CoA:3-oxoacid-CoA-transferase, TCA = tricarboxylic acid. Created with BioRender.com — **Fig. 2: Ergothioneine and ketone body metabolism in mitochondria.** Ergothioneine (EGT) is imported into mitochondria and controls mitochondrial function via direct activation of 3-mercaptopyruvate sulfurtransferase (MPST) (left panel). b-hydroxybutyrate (BHB) is imported into mitochondria and controls mitochondrial function via SCOT-dependent oxidation (right panel). 3-MP = 3-mercaptopyruvate, Pyr = pyruvate, H₂S = hydrogen sulfide, ETC = electron transport chain, OXPHOS = oxidative phosphorylation. BDH1 = D-b-hydroxybutyrate dehydrogenase 1, SCOT = succinyl-CoA:3-oxoacid-CoA-transferase, TCA = tricarboxylic acid. Created with BioRender.com

© H.-G. Sprenger

**Fig. 2: Ergothioneine and ketone body metabolism in mitochondria.** Ergothioneine (EGT) is imported into mitochondria and controls mitochondrial function via direct activation of 3-mercaptopyruvate sulfurtransferase (MPST) (left panel). b-hydroxybutyrate (BHB) is imported into mitochondria and controls mitochondrial function via SCOT-dependent oxidation (right panel). 3-MP = 3-mercaptopyruvate, Pyr = pyruvate, H₂S = hydrogen sulfide, ETC = electron transport chain, OXPHOS = oxidative phosphorylation. BDH1 = D-b-hydroxybutyrate dehydrogenase 1, SCOT = succinyl-CoA:3-oxoacid-CoA-transferase, TCA = tricarboxylic acid. Created with BioRender.com

© H.-G. Sprenger

In our lab we are investigating how the EGT-MPST axis is regulated on the molecular level and study the role of its components for cellular metabolism and during age-associated metabolic diseases. Moreover, we are interested in exploring the EGT-MPST axis during the ageing process and if activating the EGT-MPST axis has the potential to improve exercise performance independent of age and sex.

Beyond skeletal muscle we are interested in studying cell type-specific metabolic adaptations to different types of exercise training with a focus on mitochondrial metabolism. Additionally, we are keen to understand how these processes are influenced by age, diet and sex (Fig. 3). To this end we are using mouse genetics, mass-spectrometry approaches and biochemistry.

Fig. 3: Sex and age-dependent effects on cell type-specific mitochondrial metabolism upon exercise training remain largely unknown. Created with BioRender.com — **Fig. 3: Sex and age-dependent effects on cell type-specific mitochondrial metabolism upon exercise training remain largely unknown.** Created with BioRender.com

© H.-G. Sprenger

**Fig. 3: Sex and age-dependent effects on cell type-specific mitochondrial metabolism upon exercise training remain largely unknown.** Created with BioRender.com

© H.-G. Sprenger

Another exercise-sensitive pathway which is seemingly critical for healthy ageing and our lab is interested in is ketone body metabolism. Ketone body metabolism is a classic example of how cells and tissues can switch between different fuel sources to maintain energy homeostasis. During periods of diminished glucose availability, the liver produces ketone bodies from fatty acids, which are released into circulation, taken up by peripheral organs and oxidized within mitochondria to fuel the TCA cycle and increase ATP production (Fig. 2). Despite extensive knowledge about the physiological relevance of ketone body metabolism in health and disease, our knowledge about the molecular regulation of ketone body metabolism remains incomplete. We are using novel approaches to study ketone body metabolism in cell culture and in vivo to identify previously unknown regulators of ketone body metabolism.