'Cheater mitochondria' may profit from cellular stress coping mechanisms
(eLife) Cheating mitochondria may take advantage of cellular mechanisms for coping with food scarcity in a simple worm to persist, even though this can reduce the worm's wellbeing. (Source: EurekAlert! - Biology)
Source: EurekAlert! - Biology - September 22, 2020 Category: Biology Source Type: news
Feeding off fusion or the immortalization of tumor cells
(IMBA- Institute of Molecular Biotechnology of the Austrian Academy of Sciences) Despite all recent progress, cancer remains one of the deadliest human diseases. In a new publication that appeared in the journal Cell, researchers from J ü rgen Knoblich's lab at IMBA - Institute of Molecular Biotechnology of the Austrian Academy of Sciences - found a very surprising and unexpected connection between the formation of tumors and mitochondria, the power house of the cells, that allows neural stem cells that normally build our brain to become deadly tumor cells. (Source: EurekAlert! - Biology)
Source: EurekAlert! - Biology - September 11, 2020 Category: Biology Source Type: news
Mitochondrial dynamics in postmitotic cells regulate neurogenesis
We examined and manipulated mitochondrial dynamics during mouse and human cortical neurogenesis. We reveal that shortly after cortical stem cells have divided, daughter cells destined to self-renew undergo mitochondrial fusion, whereas those that retain high levels of mitochondria fission become neurons. Increased mitochondria fission promotes neuronal fate, whereas induction of mitochondria fusion after mitosis redirects daughter cells toward self-renewal. This occurs during a restricted time window that is doubled in human cells, in line with their increased self-renewal capacity. Our data reveal a postmitotic period of ...
Source: ScienceNOW - August 12, 2020 Category: Science Authors: Iwata, R., Casimir, P., Vanderhaeghen, P. Tags: Cell Biology, Neuroscience reports Source Type: news
The mitophagy effector FUNDC1 controls mitochondrial reprogramming and cellular plasticity in cancer cells
Mitochondria are signaling hubs in eukaryotic cells. Here, we showed that the mitochondrial FUN14 domain–containing protein-1 (FUNDC1), an effector of Parkin-independent mitophagy, also participates in cellular plasticity by sustaining oxidative bioenergetics, buffering ROS production, and supporting cell proliferation. Targeting this pathway in cancer cells suppressed tumor growth but rendered transformed cells more motile and invasive in a manner dependent on ROS-mediated mitochondrial dynamics and mitochondrial repositioning to the cortical cytoskeleton. Global metabolomics and proteomics profiling identified a FU...
Source: Signal Transduction Knowledge Environment - July 27, 2020 Category: Science Authors: Li, J., Agarwal, E., Bertolini, I., Seo, J. H., Caino, M. C., Ghosh, J. C., Kossenkov, A. V., Liu, Q., Tang, H.-Y., Goldman, A. R., Languino, L. R., Speicher, D. W., Altieri, D. C. Tags: STKE Research Articles Source Type: news
What Are Common Fatty Acid Oxidation Metabolic Disorders?
Discussion
All cells and particularly their mitochondria need an energy source. Glucose is one of the most common ones, but also fatty acids, lactate, pyruvate, ketones, and amino acids.
Fatty acids are formed with a carboxylic acid with a long aliphatic carbon chain usually with even numbers of carbon atoms (usually 4-28 most commonly).
Most are unbranched and in foods are usually found in the form of esters.
Fatty acids are important energy sources for the heart (50-70%) but also skeletal muscle where resting muscle uses both glucose and fatty acids. During fasting or increased stress fatty acids become a major source o...
Source: PediatricEducation.org - July 27, 2020 Category: Pediatrics Authors: Pediatric Education Tags: Uncategorized Source Type: news
Single cells have their own defenses against pathogens
New Yale research describes the role played by the mitochondria in creating an anti-microbial compound capable of combatting the cause of typhoid fever. (Source: Yale Science and Health News)
Source: Yale Science and Health News - July 24, 2020 Category: Universities & Medical Training Source Type: news
Itaconate is an effector of a Rab GTPase cell-autonomous host defense pathway against Salmonella
The guanosine triphosphatase (GTPase) Rab32 coordinates a cell-intrinsic host defense mechanism that restricts the replication of intravacuolar pathogens such as Salmonella. Here, we show that this mechanism requires aconitate decarboxylase 1 (IRG1), which synthesizes itaconate, a metabolite with antimicrobial activity. We find that Rab32 interacts with IRG1 on Salmonella infection and facilitates the delivery of itaconate to the Salmonella-containing vacuole. Mice defective in IRG1 rescued the virulence defect of a S. enterica serovar Typhimurium mutant specifically defective in its ability to counter the Rab32 defense me...
Source: ScienceNOW - July 22, 2020 Category: Science Authors: Chen, M., Sun, H., Boot, M., Shao, L., Chang, S.-J., Wang, W., Lam, T. T., Lara-Tejero, M., Rego, E. H., Galan, J. E. Tags: Immunology, Microbiology reports Source Type: news
High-fat diet with antibiotic use linked to gut inflammation
(University of California - Davis Health) UC Davis researchers have found that combining a Western-style high-fat diet with antibiotic use significantly increases the risk of developing pre- inflammatory bowel disease. This combination shuts down the mitochondria in cells of the colon lining, leading to gut inflammation. Mesalazine can help restart the mitochondria and treat pre-IBD condition. (Source: EurekAlert! - Medicine and Health)
Source: EurekAlert! - Medicine and Health - July 14, 2020 Category: International Medicine & Public Health Source Type: news
Cancer cells with defective oxidative phosphorylation require endoplasmic reticulum-to-mitochondria Ca2+ transfer for survival
Spontaneous Ca2+ signaling from the InsP3R intracellular Ca2+ release channel to mitochondria is essential for optimal oxidative phosphorylation (OXPHOS) and ATP production. In cells with defective OXPHOS, reductive carboxylation replaces oxidative metabolism to maintain amounts of reducing equivalents and metabolic precursors. To investigate the role of mitochondrial Ca2+ uptake in regulating bioenergetics in these cells, we used OXPHOS-competent and OXPHOS-defective cells. Inhibition of InsP3R activity or mitochondrial Ca2+ uptake increased α-ketoglutarate (αKG) abundance and the NAD+/NADH ratio, indicating t...
Source: Signal Transduction Knowledge Environment - July 13, 2020 Category: Science Authors: Cardenas, C., Lovy, A., Silva-Pavez, E., Urra, F., Mizzoni, C., Ahumada-Castro, U., Bustos, G., Jana, F., Cruz, P., Farias, P., Mendoza, E., Huerta, H., Murgas, P., Hunter, M., Rios, M., Cerda, O., Georgakoudi, I., Zakarian, A., Molgo, J., Foskett, J. K. Tags: STKE Research Articles Source Type: news
Scientists pinpoint surprising new function for histones
FINDINGSUCLA scientists have identified a new function for histones, the spool-shaped proteins that regulate gene expression and help pack long strands of DNA into cells. The resulting matrix, called chromatin, provides the structural foundation for chromosomes.In a surprising finding thatreceived more than 1,400 “likes” and more than 600 shares on Twitter within the first several days after the study was published, the researchers discovered that histones also function asenzymes that convertcopper into a form that can be used by the body ’s cells.Scientists had assumed that copper spontaneously converted into a usab...
Source: UCLA Newsroom: Health Sciences - July 8, 2020 Category: Universities & Medical Training Source Type: news
New link between calcium and cardiolipin in heart defects
(Texas A&M AgriLife Communications) To function properly, the heart needs energy from cells' powerhouses, the mitochondria. In turn, mitochondria boost their energy output when calcium levels rise around them, a signal that more energy is needed. A new study shows that a shortage of cardiolipin, a type of fat, in the mitochondrial membrane, prevents calcium from entering mitochondria. The result helps explain heart and muscle weakness in the rare genetic disorder Barth syndrome. (Source: EurekAlert! - Medicine and Health)
Source: EurekAlert! - Medicine and Health - July 7, 2020 Category: International Medicine & Public Health Source Type: news
Mitochondrial Dysregulation in Sepsis: A Literature Review
CONCLUSION(S): The evidence makes a compelling case for mitochondrial dysregulation to inform the current definition of sepsis as a dysregulated host response. As the evidence points to a linear, progressive time/exposure-dependent disruption in oxygen downregulation in sepsis at the cellular level, it lends credence to the recommendations for early intervention and its relationship with survivability. Time is not on the side of the individual with sepsis. (Source: Current Awareness Service for Health (CASH))
Source: Current Awareness Service for Health (CASH) - July 1, 2020 Category: Consumer Health News Source Type: news
The ER chaperone calnexin controls mitochondrial positioning and respiration
Chaperones in the endoplasmic reticulum (ER) control the flux of Ca2+ ions into mitochondria, thereby increasing or decreasing the energetic output of the oxidative phosphorylation pathway. An example is the abundant ER lectin calnexin, which interacts with sarco/endoplasmic reticulum Ca2+ ATPase (SERCA). We found that calnexin stimulated the ATPase activity of SERCA by maintaining its redox state. This function enabled calnexin to control how much ER Ca2+ was available for mitochondria, a key determinant for mitochondrial bioenergetics. Calnexin-deficient cells compensated for the loss of this function by partially shifti...
Source: Signal Transduction Knowledge Environment - June 29, 2020 Category: Science Authors: Gutierrez, T., Qi, H., Yap, M. C., Tahbaz, N., Milburn, L. A., Lucchinetti, E., Lou, P.-H., Zaugg, M., LaPointe, P. G., Mercier, P., Overduin, M., Bischof, H., Burgstaller, S., Malli, R., Ballanyi, K., Shuai, J., Simmen, T. Tags: STKE Research Articles Source Type: news
First successful delivery of mitochondria to liver cells in animals
(University of Connecticut) This experiment marks the first time researchers have ever successfully introduced mitochondria into specific cells in living animals. The study lays the groundwork to address a serious gap in treatment for liver diseases and may even eventually be used to treat other maladies throughout the body affected by mitochondrial malfunction or damage. (Source: EurekAlert! - Medicine and Health)
Source: EurekAlert! - Medicine and Health - June 25, 2020 Category: International Medicine & Public Health Source Type: news
USC-led study: Protein in mitochondria appears to regulate health and longevity
(University of Southern California) A new study led by researchers at the USC Leonard Davis School of Gerontology is the first to demonstrate that a tiny protein, humanin, has a big impact on health and longevity in both animals and humans (Source: EurekAlert! - Medicine and Health)
Source: EurekAlert! - Medicine and Health - June 24, 2020 Category: International Medicine & Public Health Source Type: news
