Decreasing intracellular entropy by increasing mitochondrial efficiency and reducing ROS formation the effect on the ageing process and age-related damage

Poljšak, Borut (author), Milisav, Irina (author)

A hypothesis is presented to explain how the ageing process might be influenced by optimizing mitochondrial efficiency to reduce intracellular entropy. Research-based quantifications of entropy are scarce. Non-equilibrium metabolic reactions and compartmentalization were found to contribute most to lowering entropy in the cells. Like the cells, mitochondria are thermodynamically open systems exchanging matter and energy with their surroundings—the rest of the cell. Based on the calculations from cancer cells, glycolysis was reported to produce less entropy than mitochondrial oxidative phosphorylation. However, these estimations depended on the CO2 concentration so that at slightly increased CO2, it was oxidative phosphorylation that produced less entropy. Also, the thermodynamic efficiency of mitochondrial respiratory complexes varies depending on the respiratory state and oxidant/antioxidant balance. Therefore, in spite of long-standing theoretical and practical efforts, more measurements, also in isolated mitochondria, with intact and suboptimal respiration, are needed to resolve the issue. Entropy increases in ageing while mitochondrial efficiency of energy conversion, quality control, and turnover mechanisms deteriorate. Optimally functioning mitochondria are necessary to meet energy demands for cellular defence and repair processes to attenuate ageing. The intuitive approach of simply supplying more metabolic fuels (more nutrients) often has the opposite effect, namely a decrease in energy production in the case of nutrient overload. Excessive nutrient intake and obesity accelerate ageing, while calorie restriction without malnutrition can prolong life. Balanced nutrient intake adapted to needs/activity-based high ATP requirement increases mitochondrial respiratory efficiency and leads to multiple alterations in gene expression and metabolic adaptations. Therefore, rather than overfeeding, it is necessary to fine-tune energy production by optimizing mitochondrial function and reducing oxidative stress; the evidence is discussed in this paper.

• Language: English
• Keywords: entropy, disorder, randomness, ageing, mitochondrial function, energy efficiency
• Work type: Article
• Typology: 1.02 - Review Article
• Organization: ZF - Faculty of Health Sciences; MF - Faculty of Medicine
• Publication status: Published
• Publication version: Version of Record
• Publication date: 07.06.2024
• Year: 2024
• Number of pages: 24 str.
• Numbering: Vol. 25, iss. 12, art. 6321
• PID: 20.500.12556/RUL-158447
• UDC: 577:544.322
• ISSN on article: 1422-0067
• DOI: 10.3390/ijms25126321
• COBISS.SI-ID: 198345219
• Publication date in RUL: 11.06.2024

Record is a part of a journal

• Title: International journal of molecular sciences
• Shortened title: Int. j. mol. sci.
• Publisher: MDPI
• ISSN: 1422-0067
• COBISS.SI-ID: 2779162

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P3-0388-2022
• Name: Mehanizmi varovanja zdravja

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P3-0019-2019
• Name: Aplikativna in bazična fiziologija in patofiziologija v medicini