Research

Our research connects human studies with mechanistic work in cell and model systems. We investigate mitochondrial function, energy metabolism and their relevance to healthy ageing and neurodegeneration, with a particular focus on methods that enable collaborative human research.

Peripheral markers of ageing and age-related disease

Illustrative study rationale and measurements. The proposed link between peripheral PBMC bioenergetics and cognitive status is under investigation; PBMC ATP is not an established diagnostic marker for mild cognitive impairment or a direct measure of brain energy metabolism.

We investigate age-related changes in mitochondrial and energy metabolism in peripheral blood cells. By studying PBMC bioenergetics alongside cognitive assessments and brain imaging, we aim to better characterize peripheral markers relevant to ageing and age-related disease.

Research focus · Human studies

Selected publications:
Dieter F et al. (2026). Mitochondrial dysfunction in peripheral mononuclear blood cells (PBMC) of individuals with mild cognitive impairment. GeroScience, 48(2), 2887–2901.

Silaidos CV et al. (2024). Age-related changes in energy metabolism in peripheral mononuclear blood cells (PBMCs) and the brains of cognitively healthy seniors. GeroScience, 46(1), 981–998.

Silaidos C et al. (2018). Sex-associated differences in mitochondrial function in human peripheral blood mononuclear cells (PBMCs) and brain. Biology of Sex Differences, 9(1), 34.

PBMC cryopreservation and bioenergetics

Workflow for PBMC isolation, cryopreservation and subsequent bioenergetic analysis in collaborative human studies.

Our PBMC cryopreservation approach supports bioenergetic analyses in collaborative human studies. Samples can be collected at partner sites, cryopreserved and shipped to Giessen for analysis, enabling a shared methodological platform across study locations.

Method platform · Open to collaboration

Selected publications:
Dieter F et al. (2026). Bioenergetic and immunological characterization of cryopreserved peripheral blood mononuclear cells (PBMCs) isolated from blood and buffy coat. Frontiers in Molecular Biosciences, 12, 1716701.

Dieter et al. (2023). Cryopreservation and Bioenergetic Evaluation of Human Peripheral Blood Mononuclear Cells. Journal of Visualized Experiments, 200, e65730.

Silaidos C et al. (2020). Time-dependent melatonin secretion is associatedwith mitochondrial function in peripheral blood mononuclear cells (PBMC) of male volunteers. Mitochondrion, 53, 21–29.

Polyphenols, mitochondria and neurodegeneration

Preclinical research pathways examining polyphenols and related metabolites in C. elegans and SH-SY5Y-APP695 cells, with mitochondrial function and Alzheimer’s-related outcomes as key endpoints.

Our ongoing preclinical research investigates fermented and cocoa polyphenols, coenzyme Q10 and curcumin metabolites in C. elegans models of ageing and Alzheimer’s disease. In SH-SY5Y-APP695 cells, we study endogenous human metabolites of polyphenols, focusing on mitochondrial function and Alzheimer’s-related cellular outcomes.

Ongoing · Preclinical research

Selected publications:
Dilberger B et al. (2021). Phenolic acid metabolites of polyphenols act as inductors for hormesis in C. elegans. Mechanisms of Ageing and Development, 198, 111518.

Grewal R et al. (2020). Purified oleocanthal and ligstroside protect against mitochondrial dysfunction in models of early Alzheimer’s disease and brain ageing. Experimental Neurology, 328, 113248.

Dilberger B et al. (2019). Polyphenols and Metabolites Enhance Survival in Rodents and Nematodes—Impact of Mitochondria. Nutrients, 11(8), 1886.

TROIA

Study framework combining physical activity groups, brain imaging and spectroscopy, cognitive and fitness assessments, and peripheral bioenergetics in adults aged 60 years and over.

TROIA investigates brain health, physical activity and peripheral bioenergetics in adults aged 60 and over, including sedentary participants, recreationally active adults and master athletes. The project combines brain imaging and spectroscopy with cognitive, fitness and bioenergetic assessments.

Funding: Carstens Foundation.

Starting soon · Kick-off: 27 October 2026 · Collaborative project with Goethe University Frankfurt

ORAMIC

Overview of the 12-week intervention comparing orange juice processing strategies and assessing PBMC mitochondrial bioenergetics and immune responses.

ORAMIC examined how orange juice processing affects bioactive compounds and their effects on mitochondrial bioenergetics and cellular immunity in a human intervention study. The collaborative project with the University of Bonn is complete; a first publication and the final report are available.

Funding: German Federal Ministry for Economic Affairs and Climate Action (BMWK), through the Industrial Collective Research programme (IGF), grant no. 01IF22262N; coordinated by the Research Association of the German Food Industry (FEI).

Completed · Collaborative project with the University of Bonn

Publication:
Quentin A et al. (2026). Technological processing of orange juice differentially modulates mitochondrial bioenergetics and immune responsiveness in human PBMCs. Journal of Functional Foods, 146, 107519.

OrAGE

Proposed study framework linking orange juice processing and product composition to systemic exposure and PBMC bioenergetic and immune outcomes.

Building on ORAMIC, OrAGE will investigate orange juice processing, ageing and related biological responses. The collaborative proposal with the University of Bonn has received a positive review and is awaiting a funding decision.

Funding decision pending · Expected 19 January 2027 · Collaborative project with the University of Bonn

The graphics were created using BioRender.