Drp1-mediated mitochondrial fission induced autophagy attenuates cell apoptosis caused by 3-chlorpropane-1,2-diol in HEK293 cells

Han

Food Science & Nutrition

et al. 2022

Acrylamide has been well known for its neurotoxicity, genotoxicity, carcinogenicity, etc. Recently, the immunotoxicity of acrylamide has been reported by different research groups, although the underlying mechanisms of acrylamide endangering immune systems have not been fully elucidated. In this study, mouse monocyte–macrophage cells model was used to clarify the toxic mechanism of acrylamide and the inhibitory effect of Yam polysaccharides (YPS) on acrylamide‐induced damage. We found that acrylamide induced RAW 264.7 cell death in a time‐ and concentration‐dependent manner. After acrylamide (2.0, 3.0, 4.0 mmol/L) treatment for 24 h, cell apoptosis, autophagy, and pyroptosis were observed. However, the levels of autophagy and pyroptosis decreased at a high concentration of acrylamide (4.0 mmol/L). Acrylamide upregulated P2X7 expression, but the P2X7 level was not showing a monotone increasing trend. When the P2X7 antagonist was applied, the effect of acrylamide on autophagy and pyroptosis was weakened. Additionally, acrylamide triggered the occurrence of oxidative stress and a decreased nitric oxide (NO) level. However, reactive oxygen species (ROS) generation, the decrease of heme oxygenase‐1 (HO‐1) expression, and the increase of inducible nitric oxide synthase (iNOS) expression were reversed by the inhibition of P2X7. Yam polysaccharides (50.0 μg/ml) significantly inhibited acrylamide‐induced oxidative stress and cell death (including apoptosis, autophagy, and pyroptosis). Yam polysaccharides also effectively reversed the increase of iNOS expression induced by acrylamide. However, Yam polysaccharides promoted the expression of P2X7 rather than prohibit it. These results indicated that acrylamide caused RAW 264.7 cell death due to pro‐apoptosis as well as excessive autophagy and pyroptosis. Apoptosis might be more predominant than autophagy and pyroptosis under a higher concentration of acrylamide (4.0 mmol/L). P2X7‐stimulated oxidative stress was responsible for acrylamide‐induced programmed cell death (PCD), but P2X7 showed limited regulatory effect on apoptosis. Yam polysaccharides with antioxidant activity inhibited acrylamide‐induced cell death (apoptosis, autophagy, and pyroptosis), but exerted limited effect on the acrylamide‐induced P2X7 expression. These findings would offer an insight into elucidating the immunotoxic mechanism of acrylamide and the potential approaches to control its toxicity.

Section: Discussionmentioning

confidence: 99%

The inhibitory effect of Yam polysaccharides on acrylamide‐induced programmed cell death in RAW 264.7 cells

Han

Food Science & Nutrition

et al. 2022

“…This is essential for the production of sufficient mitochondria in developing cells, the energy metabolism, the spread and inheritance of mitochondria, and the removal of damaged or dysfunctional mitochondria via mitophagy [48][49][50][51]. Fission also facilitates apoptosis through the release of cytochrome c, playing a crucial role in this process [52,53].…”

Section: Mitochondrial Damage-associated Molecular Patterns In Innate...mentioning

confidence: 99%

Mitochondrial Damage-Associated Molecular Patterns and Metabolism in the Regulation of Innate Immunity

Lyu,

Wang,

Huang

et al. 2023

J Innate Immun

The innate immune system, as the host’s first line of defense against intruders, plays a critical role in recognizing, identifying, and reacting to a wide range of microbial intruders. There is increasing evidence that mitochondrial stress is a major initiator of innate immune responses. When mitochondria’s integrity is disrupted or dysfunction occurs, the mitochondria’s contents are released into the cytosol. These contents, like reactive oxygen species, mitochondrial DNA, and double-stranded RNA, among others, act as damage-related molecular patterns (DAMPs) that can bind to multiple innate immune sensors, particularly pattern recognition receptors, thereby leading to inflammation. To avoid the production of DAMPs, in addition to safeguarding organelles integrity and functionality, mitochondria may activate mitophagy or apoptosis. Moreover, mitochondrial components and specific metabolic regulations modify properties of innate immune cells. These include macrophages, dendritic cells, innate lymphoid cells, and so on, in steady state or in stimulation that are involved in processes ranging from the tricarboxylic acid cycle to oxidative phosphorylation and fatty acid metabolism. Here we provide a brief summary of mitochondrial DAMPs’ initiated and potentiated inflammatory response in the innate immune system. We also provide insights into how the state of activation, differentiation, and functional polarization of innate immune cells can be influenced by alteration to the metabolic pathways in mitochondria.

“…Acute myeloid leukemia (AML) is hierarchical with leukemic stem cells and progenitor cells giving rise to mature and differentiated blasts. Like HSCs, AML cells have unique mitochondrial and metabolic features with reliance on OXPHOS [158]. Recently, the mitochondrial transacylase tafazzin (TAZ) was demonstrated to regulate AML stemness by modulating intracellular levels of phospholipids [159].…”

Section: Cancer Stem Cell Metabolismmentioning

confidence: 99%

Mitochondria at Work: New Insights into Regulation and Dysregulation of Cellular Energy Supply and Metabolism

Schirrmacher¹

2020

Biomedicines

Mitochondria are of great relevance to health, and their dysregulation is associated with major chronic diseases. Research on mitochondria—156 brand new publications from 2019 and 2020—have contributed to this review. Mitochondria have been fundamental for the evolution of complex organisms. As important and semi-autonomous organelles in cells, they can adapt their function to the needs of the respective organ. They can program their function to energy supply (e.g., to keep heart muscle cells going, life-long) or to metabolism (e.g., to support hepatocytes and liver function). The capacity of mitochondria to re-program between different options is important for all cell types that are capable of changing between a resting state and cell proliferation, such as stem cells and immune cells. Major chronic diseases are characterized by mitochondrial dysregulation. This will be exemplified by cardiovascular diseases, metabolic syndrome, neurodegenerative diseases, immune system disorders, and cancer. New strategies for intervention in chronic diseases will be presented. The tumor microenvironment can be considered a battlefield between cancer and immune defense, competing for energy supply and metabolism. Cancer cachexia is considered as a final stage of cancer progression. Nevertheless, the review will present an example of complete remission of cachexia via immune cell transfer. These findings should encourage studies along the lines of mitochondria, energy supply, and metabolism.