Search Results (10)

The kidney is a highly specialized organ that maintains systemic homeostasis through tightly coordinated cellular and molecular mechanisms. Renal parenchymal cells regulate metabolic waste excretion, electrolyte and acid–base balance, and blood pressure control—functions that rely on the dynamic integration of intracellular organelles. Recent advances in molecular and biochemical research have highlighted how inter-organelle communication is essential for preserving renal cell function and adaptive responses to stress. This review focuses on the molecular crosstalk among key organelles—including the nucleus, endoplasmic reticulum (ER), Golgi apparatus, mitochondria, lysosomes, and peroxisomes—primarily in tubular epithelial cells. We discuss how these interactions coordinate metabolic signaling, protein homeostasis, redox balance, and energy production and how their disruption contributes to maladaptive pathways during acute kidney injury (AKI), ultimately promoting chronic kidney disease (CKD) transition. Particular focus is placed on emerging pathways linking organelle dysfunction to inflammation, fibrosis, and metabolic reprogramming. Furthermore, we highlight recent advances in genetics and molecular therapeutics targeting organelle communication, including modulation of ER stress responses, mitochondrial biogenesis, and lysosomal function. Clinically approved agents, such as mTOR inhibitors, and experimental approaches—such as chemical chaperones and mitochondrial transplantation—demonstrate the potential to restore organelle homeostasis and mitigate renal injury. Overall, elucidating the molecular networks governing organelle crosstalk provides critical insights into kidney disease pathogenesis and identifies novel targets for therapeutic intervention in AKI-to-CKD transition. Full article

The endoplasmic reticulum (ER) is a central hub of cellular proteostasis, coordinating protein folding, lipid metabolism, calcium signaling, and inter-organelle communication. Disruptions in ER function activate the unfolded protein response (UPR), an evolutionarily conserved signaling network mediated by PERK, IRE1α, and ATF6. Initially viewed primarily as a stress-mitigating mechanism, the UPR is now recognized as a central coordinator of diverse cellular stress-response pathways. This review focuses on mechanistic insights into UPR signaling, with particular emphasis on its crosstalk with oxidative stress regulation, mitochondrial function and mitochondria–ER contact sites, autophagy, inflammatory signaling, and metabolic sensing. The analysis integrates evidence from biochemical and structural studies, genetic and pharmacological perturbation models, and selected in vivo investigations from PubMed and Google Scholar between 2000 and 2025, focusing on mechanistic, experimental and translational studies addressing UPR signaling and ER stress. Together, these studies demonstrate how transient UPR activation promotes cellular adaptation through coordinated transcriptional, translational, and organelle-specific responses. We further discuss how sustained or unresolved ER stress alters UPR outputs, shifting signaling toward maladaptive outcomes such as mitochondrial dysfunction, dysregulated autophagy, oxidative imbalance, and apoptosis. By placing the UPR within a network of interconnected stress pathways, this work provides a framework for understanding how ER proteostasis is linked to cell fate decisions under stress. Full article

Peroxisomes are multifunctional organelles that play essential roles in lipid metabolism, redox regulation, and cellular signaling. An expanding body of evidence implicates peroxisomal dysfunction as a key contributor to aging and age-related diseases. Aging is accompanied by progressive declines in key peroxisomal functions, including catalase activity, fatty acid β-oxidation, plasmalogen biosynthesis, and the metabolism of bile acids and docosahexaenoic acid, resulting in increased oxidative stress, lipid dysregulation, and alterations in membrane composition. Impaired pexophagy further exacerbates these defects by allowing the accumulation of damaged peroxisomes and compromising cellular homeostasis. Through extensive metabolic and signaling crosstalk with mitochondria, the endoplasmic reticulum, and lysosomes, peroxisomal dysfunction can propagate oxidative and metabolic disturbances throughout the cell. In addition, peroxisome-derived signaling molecules, such as hydrogen peroxide and bioactive lipids, link peroxisomal activity to cellular stress responses and organismal metabolic homeostasis. We propose that aging-associated impairments in peroxisomal protein import, redox regulation, and selective turnover progressively shift peroxisomes from adaptive metabolic signaling hubs toward sources of chronic oxidative and lipid stress. In this context, current studies highlight peroxisomal homeostasis as a potential determinant of healthy aging and point to peroxisomal pathways as emerging targets for intervention in age-related disease. Full article

Cardiovascular and metabolic disorders significantly reduce healthspan and lifespan, with oxidative stress being a major contributing factor. Oxidative stress, marked by elevated reactive oxygen species (ROS), disrupts cellular and systemic functions. One proposed mechanism involves TRPM2 (Transient Receptor Potential Melastatin2)-dependent Ca²⁺ dysregulation. These channels, activated by ROS (via ADP-ribose), not only respond to ROS but also amplify it, creating a self-sustaining cycle. Recent studies suggest that TRPM2 activation triggers a cascade of signals from intracellular organelles, enhancing ROS production and affecting cell physiology and viability. This review examines the role of TRPM2 channels in oxidative stress-associated cardiovascular and metabolic diseases. Oxidative stress induces TRPM2-mediated Ca²⁺ influx, leading to lysosomal damage and the release of Zn²⁺ from lysosomal stores to the mitochondria. In mitochondria, Zn²⁺ facilitates electron leakage from respiratory complexes, reducing membrane potential, increasing ROS production, and accelerating mitochondrial degradation. Excess ROS activates PARP1 in the nucleus, releasing ADP-ribose, a TRPM2 agonist, thus perpetuating the cycle. Lysosomes act as Ca²⁺-sensitive signalling platforms, delivering toxic Zn²⁺ signals to mitochondria. This represents a paradigm shift, proposing that the toxic effects of Ca²⁺ on mitochondria are not direct, but are instead mediated by lysosomes and subsequent Zn²⁺ release. This cycle exhibits a ‘domino’ effect, causing sequential and progressive decline in the function of lysosomes, mitochondria, and the nucleus—hallmarks of ageing and oxidative stress-related cardiovascular and metabolic diseases. These insights could lead to new therapeutic strategies for addressing the widespread issue of cardiovascular and metabolic diseases. Full article

Reactive oxygen species (ROS) are critical signalling molecules, but their overproduction leads to oxidative stress (OS), a common denominator in the pathogenesis of numerous non-communicable diseases (NCDs) and aging. General antioxidant therapies have largely been unsuccessful, highlighting the need for a deeper understanding of ROS amplification mechanisms to develop targeted interventions. This review proposes a unified, self-amplifying “vicious cycle” of inter-organelle crosstalk that drives pathological ROS elevation and cellular damage. We outline a pathway initiated by extracellular stressors that co-activate plasma membrane TRPM2 channels and NADPH oxidase-2. This synergy elevates cytoplasmic Ca²⁺, leading to lysosomal dysfunction and permeabilization, which in turn releases sequestered Zn²⁺. Mitochondrial uptake of this labile Zn²⁺ impairs electron transport chain function, particularly at Complex III, resulting in mitochondrial fragmentation, loss of membrane potential and a burst of mitochondrial ROS (mtROS). These mtROS diffuse to the nucleus, activating PARP-1 and generating ADPR, which further stimulates TRPM2, thereby perpetuating the cycle. This “circular domino effect” integrates signals generated across the plasma membrane (Ca²⁺), lysosomes (Zn²⁺), mitochondria (ROS) and nucleus (ADPR), leading to progressive organelle failure, cellular dysfunction, and ultimately cell death. Understanding and targeting specific nodes within this TRPM2-NOX2-Ca²⁺-Zn²⁺-mtROS-ADPR axis offers novel therapeutic avenues for NCDs by selectively disrupting pathological ROS amplification while preserving essential physiological redox signalling. Full article

The perception of lysosomes and mitochondria as entirely separate and independent entities that degrade material and produce ATP, respectively, has been challenged in recent years as not only more complex roles for both organelles, but also an unanticipated level of interdependence are being uncovered. Coupled lysosome and mitochondrial function and dysfunction involve complex crosstalk between the two organelles which goes beyond mitochondrial quality control and lysosome-mediated clearance of damaged mitochondria through mitophagy. Our understanding of crosstalk between these two essential metabolic organelles has been transformed by major advances in the field of membrane contact sites biology. We now know that membrane contact sites between lysosomes and mitochondria play central roles in inter-organelle communication. This importance of mitochondria–lysosome contacts (MLCs) in cellular homeostasis, evinced by the growing number of diseases that have been associated with their dysregulation, is starting to be appreciated. How MLCs are regulated and how their coordination with other pathways of lysosome–mitochondria crosstalk is achieved are the subjects of ongoing scrutiny, but this review explores the current understanding of the complex crosstalk governing the function of the two organelles and its impact on cellular stress and disease. Full article

Advanced multiomics analysis has revealed novel pathophysiological mechanisms in kidney disease. In particular, proteomic and metabolomic analysis shed light on mitochondrial dysfunction (mitochondrial stress) by glycation in diabetic or age-related kidney disease. Further, metabolic damage often results from organelle stress, such as mitochondrial stress and endoplasmic reticulum (ER) stress, as well as interorganelle communication, or “organelle crosstalk”, in various kidney cells. These contribute to progression of the disease phenotype. Aberrant tubular mitochondrial lipid metabolism leads to tubular inflammation and fibrosis. This review article summarizes updated evidence regarding organelle stress, organelle crosstalk, and metabolic derangement in kidney disease. Full article

The heart is an organ with high-energy demands in which the mitochondria are most abundant. They are considered the powerhouse of the cell and occupy a central role in cellular metabolism. The intermyofibrillar mitochondria constitute the majority of the three-mitochondrial subpopulations in the heart. They are also considered to be the most important in terms of their ability to participate in calcium and cellular signaling, which are critical for the regulation of mitochondrial function and adenosine triphosphate (ATP) production. This is because they are located in very close proximity with the endoplasmic reticulum (ER), and for the presence of tethering complexes enabling interorganelle crosstalk via calcium signaling. Calcium is an important second messenger that regulates mitochondrial function. It promotes ATP production and cellular survival under physiological changes in cardiac energetic demand. This is accomplished in concert with signaling pathways that regulate both calcium cycling and mitochondrial function. Perturbations in mitochondrial homeostasis and metabolic remodeling occupy a central role in the pathogenesis of heart failure. In this review we will discuss perturbations in ER-mitochondrial crosstalk and touch on important signaling pathways and molecular mechanisms involved in the dysregulation of calcium homeostasis and mitochondrial function in heart failure. Full article

Over the past decades, peroxisomes have emerged as key regulators in overall cellular lipid and reactive oxygen species metabolism. In mammals, these organelles have also been recognized as important hubs in redox-, lipid-, inflammatory-, and innate immune-signaling networks. To exert these activities, peroxisomes must interact both functionally and physically with other cell organelles. This review provides a comprehensive look of what is currently known about the interconnectivity between peroxisomes and mitochondria within mammalian cells. We first outline how peroxisomal and mitochondrial abundance are controlled by common sets of cis- and trans-acting factors. Next, we discuss how peroxisomes and mitochondria may communicate with each other at the molecular level. In addition, we reflect on how these organelles cooperate in various metabolic and signaling pathways. Finally, we address why peroxisomes and mitochondria have to maintain a healthy relationship and why defects in one organelle may cause dysfunction in the other. Gaining a better insight into these issues is pivotal to understanding how these organelles function in their environment, both in health and disease. Full article

The dynamic interplay among intracellular organelles occurs at specific membrane tethering sites, where two organellar membranes come in close apposition but do not fuse. Such membrane microdomains allow for rapid and efficient interorganelle communication that contributes to the maintenance of cell physiology. Pathological conditions that interfere with the proper composition, number, and physical vicinity of the apposing membranes initiate a cascade of events resulting in cell death. Membrane contact sites have now been identified that tether the extensive network of the endoplasmic reticulum (ER) membranes with the mitochondria, the plasma membrane (PM), the Golgi and the endosomes/lysosomes. Thus far, the most extensively studied are the MAMs, or mitochondria associated ER membranes, and the ER-PM junctions that share functional properties and crosstalk to one another. Specific molecular components that define these microdomains have been shown to promote the interaction in trans between these intracellular compartments and the transfer or exchange of Ca²⁺ ions, lipids, and metabolic signaling molecules that determine the fate of the cell. Full article