PhD Scientific Days 2023

Pathology - Posters C

Supraphysiological Concentrations of Choline Oxidized in Mitochondria Support the Forward Operation of Adenine Nucleotide Translocase When Complex I is Inhibited

Előadó neve

Pallag, Gergely, MSc

Neptun code

YWBXJ7

Előadó munkahelye

Department of Biochemistry and Molecular Biology, Semmelweis University

Előadó telefonszáma

+36307030427

Előadó e-mail címe

pallag.gergely@semmelweis-univ.hu

Az előadás címe

Supraphysiological Concentrations of Choline Oxidized in Mitochondria Support the Forward Operation of Adenine Nucleotide Translocase When Complex I is Inhibited

Szerző(k) neve és munkahelye

Gergely Pallag, Department of Biochemistry and Molecular Biology, Semmelweis University, Budapest
Victoria Azarov, Department of Biochemistry and Molecular Biology, Semmelweis University, Budapest
Christos, Chinopoulos, Department of Biochemistry and Molecular Biology, Semmelweis University, Budapest

Bemutatás módja

Poszter

Szekció

Pathology - Posters C

Language of the presentation

Hungarian

Preferred session

Pathology and Oncology

Összefoglaló szövege

Introduction
The oxidation of choline to betaine aldehyde leads to the transfer of electrons to ubiquinone in mitochondria that express choline dehydrogenase (Cdh). This electron transfer supports complexes III and IV, thus generating the protonmotive force. Further catabolism of betaine aldehyde depends on CI activity due to NAD+ requirement.

Aims
Our aim was to investigate the effect of the choline catabolism on the mitochondrial membrane potential and its effect on the ANT and F1Fo-ATPase directionality in isolated mouse liver mitochondria

Method
In complex I-inhibited, mouse liver mitochondria, the directionalities of adenine nucleotide translocase (ANT) and F1Fo-ATPase were estimated by the instantaneous effect of their respective inhibitors, carboxyatractyloside vs oligomycin, on membrane potential. In addition, matrix NADH levels were also recorded.

Results
Choline, at concentrations higher than those reported in physiological contexts in the literature, generated a sufficiently high mitochondrial membrane potential to sustain ANT operation in the forward mode in CI-inhibited mouse liver mitochondria. This was not observed when either CIII or CIV were inhibited. The directionality of the F1Fo-ATPase was unaffected by choline catabolism.

Conclusion
The data show that Cdh-mediated choline catabolism could generate sufficient CIII and CIV proton pumping, thus supporting ANT operation in forward mode even under CI inhibition, but only if used at supraphysiological levels.

University and Doctoral School

Semmelweis University, János Szentágothai Doctoral School of Neurosciences

Supervisor

Christos, Chinopoulos MD, PhD

Publication of my abstract

I give consent to the publication of my abstract on the website of the congress.

Kind

Szabad

Status

elfogadva

Accepted presentation method

poszter

Előadás fájl jóváhagyás

nem rendelkezett róla

Előadó

5055

Start

11:36

End

11:41

Authors (legacy)

Gergely Pallag, Department of Biochemistry and Molecular Biology, Semmelweis University, Budapest
Victoria Azarov, Department of Biochemistry and Molecular Biology, Semmelweis University, Budapest
Christos, Chinopoulos, Department of Biochemistry and Molecular Biology, Semmelweis University, Budapest