Protocol to separate small and large extracellular vesicles from mouse and human cardiac tissues.

Extracellular vesicles (EVs) are secreted by cells under various conditions and can contribute to the disease progression in tissues. Here, we present a protocol to separate small and large EVs from mouse hearts and cardiac tissues collected from patients. We describe steps for utilizing enzymatic digestion for release of EVs from interstitial space followed by differential centrifugation and immunoaffinity purification.

Potential exhaled breath biomarkers identified in chlorine-exposed mice.

Exhaled breath (EB) contains various volatile organic compounds (VOCs) that can indicate specific biological or pathological processes in the body. Analytical techniques like gas chromatography-mass spectrometry (GC-MS) can be used to detect and measure these exhaled biomarkers. In this study, the objective was to develop a non-invasive method of EB sampling in animals that were awake, as well as to analyze EB for volatile biomarkers specific for chlorine exposure and/or diagnostic biomarkers for chlorine-induced acute lung injury (ALI).

Mitochondria are secreted in extracellular vesicles when lysosomal function is impaired.

Mitochondrial quality control is critical for cardiac homeostasis as these organelles are responsible for generating most of the energy needed to sustain contraction. Dysfunctional mitochondria are normally degraded via intracellular degradation pathways that converge on the lysosome. Here, we identified an alternative mechanism to eliminate mitochondria when lysosomal function is compromised.

Cancer-cell-secreted extracellular vesicles target p53 to impair mitochondrial function in muscle.

Skeletal muscle loss and weakness are associated with bad prognosis and poorer quality of life in cancer patients. Tumor-derived factors have been implicated in muscle dysregulation by inducing cachexia and apoptosis. Here, we show that extracellular vesicles secreted by breast cancer cells impair mitochondrial homeostasis and function in skeletal muscle, leading to decreased mitochondrial content and energy production and increased oxidative stress.

Deciphering functional roles and interplay between Beclin1 and Beclin2 in autophagosome formation and mitophagy.

The degradation of macromolecules and organelles by the process of autophagy is critical for cellular homeostasis and is often compromised during aging and disease. Beclin1 and Beclin2 are implicated in autophagy induction, and these homologs share a high degree of amino acid sequence similarity but have divergent N-terminal regions. Here, we investigated the functions of the Beclin homologs in regulating autophagy and mitophagy, a specialized form of autophagy that targets mitochondria.

Estimated daily intake of per- and polyfluoroalkyl substances related to different particle size fractions of house dust.

Indoor environmental pollutants are a threat to human health. In the current study, we analysed 25 per- and polyfluoroalkyl substances (PFASs) in seven different size fraction of house dust including the two relevant for exposure via ingestion and inhalation. The highest PFAS concentration is found in the inhalable particulate fraction which is explained by the increased surface area as the particulate's sizes decrease.

Mcl-1 Differentially Regulates Autophagy in Response to Changes in Energy Status and Mitochondrial Damage.

Myeloid cell leukemia-1 () is a unique antiapoptotic Bcl-2 member that is critical for mitochondrial homeostasis. Recent studies have demonstrated that 's functions extend beyond its traditional role in preventing apoptotic cell death. Specifically, data suggest that plays a regulatory role in autophagy, an essential degradation pathway involved in recycling and eliminating dysfunctional organelles.

The role of mitochondrial fission in cardiovascular health and disease.

Mitochondria are organelles involved in the regulation of various important cellular processes, ranging from ATP generation to immune activation. A healthy mitochondrial network is essential for cardiovascular function and adaptation to pathological stressors. Mitochondria undergo fission or fusion in response to various environmental cues, and these dynamic changes are vital for mitochondrial function and health.

Chlorine exposure induces Caspase-3 independent cell death in human lung epithelial cells.

Chlorine (Cl) is a common toxic industrial gas and human inhalation exposure causes tissue damage with symptoms ranging from wheezing to more severe symptoms such as lung injury or even death. Because the mechanism behind Cl-induced cell death is not clearly understood, the present study aimed to study the cellular effects in vitro after Cl exposure of human A549 lung epithelial cells. In addition, the possible treatment effects of the anti-inflammatory antioxidant N-acetyl cysteine (NAC) were evaluated.

Mitochondrial quality surveillance: mitophagy in cardiovascular health and disease.

Selective autophagy of mitochondria, known as mitophagy, is a major quality control pathway in the heart that is involved in removing unwanted or dysfunctional mitochondria from the cell. Baseline mitophagy is critical for maintaining fitness of the mitochondrial network by continuous turnover of aged and less-functional mitochondria. Mitophagy is also critical in adapting to stress associated with mitochondrial damage or dysfunction.

Cardiolipin Remodeling Defects Impair Mitochondrial Architecture and Function in a Murine Model of Barth Syndrome Cardiomyopathy.

Background: Cardiomyopathy is a major clinical feature in Barth syndrome (BTHS), an X-linked mitochondrial lipid disorder caused by mutations in (), encoding a mitochondrial acyltransferase required for cardiolipin remodeling. Despite recent description of a mouse model of BTHS cardiomyopathy, an in-depth analysis of specific lipid abnormalities and mitochondrial form and function in an in vivo BTHS cardiomyopathy model is lacking.

Methods: We performed in-depth assessment of cardiac function, cardiolipin species profiles, and mitochondrial structure and function in our newly generated cardiomyocyte-specific knockout mice and Cre-negative control mice (n≥3 per group).

Loss of Parkin Results in Altered Muscle Stem Cell Differentiation during Regeneration.

The high capacity of the skeletal muscle to regenerate is due to the presence of muscle stem cells (MuSCs, or satellite cells). The E3 ubiquitin ligase Parkin is a key regulator of mitophagy and is recruited to mitochondria during differentiation of mouse myoblast cell line. However, the function of mitophagy during regeneration has not been investigated in vivo.

Mcl-1-mediated mitochondrial fission protects against stress but impairs cardiac adaptation to exercise.

Myeloid cell leukemia-1 (Mcl-1) is a structurally and functionally unique anti-apoptotic Bcl-2 protein. While elevated levels of Mcl-1 contribute to tumor cell survival and drug resistance, loss of Mcl-1 in cardiac myocytes leads to rapid mitochondrial dysfunction and heart failure development. Although Mcl-1 is an anti-apoptotic protein, previous studies indicate that its functions extend beyond regulating apoptosis.

Aging is associated with a decline in Atg9b-mediated autophagosome formation and appearance of enlarged mitochondria in the heart.

Advancing age is a major risk factor for developing heart disease, and the biological processes contributing to aging are currently under intense investigation. Autophagy is an important cellular quality control mechanism that is reduced in tissues with age but the molecular mechanisms underlying the age-associated defects in autophagy remain poorly characterized. Here, we have investigated how the autophagic process is altered in aged mouse hearts.

Mitochondrial Quality Control and Cellular Proteostasis: Two Sides of the Same Coin.

Mitochondrial dysfunction is a hallmark of cardiac pathophysiology. Defects in mitochondrial performance disrupt contractile function, overwhelm myocytes with reactive oxygen species (ROS), and transform these cellular powerhouses into pro-death organelles. Thus, quality control (QC) pathways aimed at identifying and removing damaged mitochondrial proteins, components, or entire mitochondria are crucial processes in post-mitotic cells such as cardiac myocytes.