Doxycycline Impairs Mitochondrial Function and Protects Human Glioma Cells from Hypoxia-Induced Cell Death: Implications of Using Tet-Inducible Systems

Abstract

Inducible gene expression is an important tool in molecular biology research to study protein function. Most frequently, the antibiotic doxycycline is used for regulation of so-called tetracycline (Tet)-inducible systems. In contrast to stable gene overexpression, these systems allow investigation of acute and reversible effects of cellular protein induction. Recent reports have already called for caution when using Tet-inducible systems as the employed antibiotics can disturb mitochondrial function and alter cellular metabolism by interfering with mitochondrial translation. Reprogramming of energy metabolism has lately been recognized as an important emerging hallmark of cancer and is a central focus of cancer research. Therefore, the scope of this study was to systematically analyze dose-dependent metabolic effects of doxycycline on a panel of glioma cell lines with concomitant monitoring of gene expression from Tet-inducible systems. We report that doxycycline doses commonly used with inducible expression systems (0.01–1 µg/mL) substantially alter cellular metabolism: Mitochondrial protein synthesis was inhibited accompanied by reduced oxygen and increased glucose consumption. Furthermore, doxycycline protected human glioma cells from hypoxia-induced cell death. An impairment of cell growth was only detectable with higher doxycycline doses (10 µg/mL). Our findings describe settings where doxycycline exerts effects on eukaryotic cellular metabolism, limiting the employment of Tet-inducible systems.

Doublecortin-Like Is Implicated in Adult Hippocampal Neurogenesis and in Motivational Aspects to Escape from an Aversive Environment in Male Mice

“…As control, we used non-induced TG animals that were fed on identical control diet without dox (S4207, BioServ, New Jersey, USA). As tetracycline-based antibiotics alter mitochondrial function, cell metabolism, cell proliferation and survival (Ahler et al, 2013;Chatzispyrou, Held, Mouchiroud, Auwerx, & Houtkooper, 2015;Luger et al, 2018), we used two additional control groups: wildtype littermates fed with chow and fed with dox containing food pellets.…”

Sulfide (Na2S) and Polysulfide (Na2S2) Interacting with Doxycycline Produce/Scavenge Superoxide and Hydroxyl Radicals and Induce/Inhibit DNA Cleavage

“…OXYT modulates inflammatory response [20] and TETR has an effect on growing bones and teeth [21]. DOXY induces cell death, has an anti-apoptotic function or induces apoptosis, reduces or induces ROS, triggers inflammation, reduces cardiac attack, protects cells or renal function from hypoxia-induced injury, prevents proliferation, reduces tumor growth, and suppresses a process of metastasis in human breast or prostate cancer models (for a review see [22,23,24,25,26,27]). Molecular mechanisms of these tetracyclines’ side effects are not fully understood yet and remain to be examined thoroughly.…”

The Role of Mitochondria in Drug-Induced Kidney Injury

“…The extensive experimental evidence on the impact of tetracyclines on mitochondria not only shed light on the molecular mechanisms of tetracycline-induced toxicity but also raised awareness within the scientific community on the use of these antibiotics for inducible gene expression in the Tet-ON/Tet-OFF system. The mitochondrial dysregulation associated with the use of these antibiotics may be a relevant pitfall in the study of mitochondrial-related disorders ( Chatzispyrou et al, 2015 ; Moullan et al, 2015 ; Luger et al, 2018 ).…”