Lipid peroxidation is involved in calcium dependent upregulation of mitochondrial metabolism in skeletal muscle

Abstract

2',7'-dichlorfluorescein-diacetate (DCFH-DA); 4-hydroxynonenal (4-HNE); adenosine triphosphate (ATP); carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone (FCCP); cytosolic calcium concentration ([Ca 2+ ]c); dihydroethidium probe (DHE); Dulbecco's Modified Eagle's Medium (DMEM); extracellular acidification rates (ECAR); fetal bovine serum (FBS); gene of interest (GOI); horse serum (HS); housekeeping gene (HKG); lipid peroxidation (LPO); oxygen consumption rates (OCR); polyunsaturated fatty acids (PUFA); reactive oxygen species (ROS); relative fluorescence units (RFU); threshold cycle (CT) Summary Background: Skeletal muscle cells continuously generate reactive oxygen species (ROS). Excessive ROS can affect lipids resulting in lipid peroxidation (LPO). Here we investigated the effects of myotube contraction on the LPO induction and the impact of LPO-product 4-hydroxynonenal (4-HNE) on physiology/pathology of myotubes using C2C12 myoblasts. Methods: C2C12 myoblasts were differentiated into myotubes, stimulated with caffeine and analyzed for the induction of LPO and formation of 4-HNE protein adducts. Further effects of 4-HNE on mitochondrial bioenergetics, NADH level, mitochondrial density and expression of mitochondrial metabolism genes were determined. Results: Short and long-term caffeine stimulation of myotubes promoted superoxide production, LPO and formation of 4-HNE protein adducts. Furthermore, low 4-HNE concentrations had no effect on myotube viability and cellular redox homeostasis, while concentrations from 10µM and above reduced myotube viability and significantly disrupted homeostasis. A time and dose-dependent 4-HNE effect on superoxide production and mitochondrial NADH-autofluorescence was observed. Finally, 4-HNE had strong impact on maximal respiration, spare respiratory capacity, ATP production, coupling efficiency of mitochondria and mitochondrial density. Conclusion: Data presented in this work make evident for the first time that pathological 4-HNE levels elicit damaging effects on skeletal muscle cells while acute exposure to physiological 4-HNE induces transient adaptation. General significance: This work suggests an important role of 4-HNE on the regulation of myotube's mitochondrial metabolism and cellular energy production. It further signifies the importance of skeletal muscle cells hormesis in response to acute stress in order to maintain essential biological functions.

The NRF2, Thioredoxin, and Glutathione System in Tumorigenesis and Anticancer Therapies

“…4-HNE can act either directly or by forming adducts with macromolecules, such as proteins [ 27 ] or nucleic acids [ 28 , 29 ]. Consequently, 4-HNE can modulate various cellular functions of non-malignant as well as cancer cells [ 30 , 31 , 32 , 33 ] and can play a role in tumorigenesis [ 34 , 35 , 36 ].…”

Mitochondria and lipid peroxidation in the mechanism of neurodegeneration: Finding ways for prevention

“…Interestingly, the brain, as in the case with oxygen and glucose, consumes 20% of all PUFAs of the body which suggests a high level of lipid turnover in this organ. Products of lipid peroxidation are constantly generated and used for signaling and housekeeping needs 7–9 . The products of lipid peroxidation are utilized enzymatically to hydroxyl acids by glutathione peroxidase, using glutathione (GSH) as a cosubstrate to reduce lipid peroxides to the corresponding alcohols 10 or, to aldehydes 6,11 (Figure 1D).…”

Analysis of Multiple Mycotoxins in the Qatari Population and Their Relation to Markers of Oxidative Stress

“…Excessive ROS, based on their reactivity and the proximity of target molecules, can modulate signaling pathways, modify macromolecules or induce cell death [ 8 , 9 , 10 ]. The peroxidation of lipids leads to the formation of reactive aldehydes that have a longer lifetime than ROS, can move across membranes and affect targets distant from the initial site of oxidative injury [ 11 , 12 ]. Thus, in the current study, the aim was to provide an epidemiological “snapshot” of population exposure to mycotoxins by assessing the incidence of their biomarkers in the serum and urine samples of larger cohort using multimycotoxin approaches.…”