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International Journal of Radiation... 2024This study proposes to investigate the effects of microwave radiation and its thermal effects, compared to thermal effects alone, on the bioenergetics of mitochondria...
AIMS
This study proposes to investigate the effects of microwave radiation and its thermal effects, compared to thermal effects alone, on the bioenergetics of mitochondria isolated from mouse liver.
METHODS
The main parameters investigated in this study are mitochondrial respiration (coupled states: S3 and S4; uncoupled state), using a high-resolution respirometer, and swelling, using a spectrophotometer.
RESULTS
Mitochondria irradiated at 2.45 GHz microwave with doses 0.085, 0.113 and 0.141 kJ/g, presented a decrease in S3 and uncoupled state, but an increase in S4. Conversely, mitochondria thermally treated at 40, 44 and 50 °C presented an increasing in S3 and S4, while uncoupled state was unaltered. Mitochondrial swelling increases as a function of the dose or temperature, indicating membrane damages in both cases.
CONCLUSION
Microwave radiation and thermal effect alone indicated different bioenergetics mitochondria response. These results imply that the effects due to microwave in medical treatment are not exclusively due to the increase in temperature, but a combination of electromagnetic and thermal effects.
Topics: Microwaves; Animals; Mice; Energy Metabolism; Mitochondria, Liver; Male; Dose-Response Relationship, Radiation; Temperature; Mitochondrial Swelling; Cell Respiration
PubMed: 38843455
DOI: 10.1080/09553002.2024.2348073 -
Drug Development Research Jun 2024It has been reported that lipophilic statins such as atorvastatin can more readily penetrate into β-cells and reach the mitochondria, resulting in mitochondrial...
Hesperidin, vanillic acid, and sinapic acid attenuate atorvastatin-induced mitochondrial dysfunction via inhibition of mitochondrial swelling and maintenance of mitochondrial function in pancreas isolated mitochondria.
It has been reported that lipophilic statins such as atorvastatin can more readily penetrate into β-cells and reach the mitochondria, resulting in mitochondrial dysfunction, oxidative stress, decrease in insulin release. Many studies have shown that natural products can protect mitochondrial dysfunction induced by drug in different tissue. We aimed to explore mitochondrial protection potency of hesperidin, vanillic acid, and sinapic acid as natural compounds against mitochondrial dysfunction induced by atorvastatin in pancreas isolated mitochondria. Mitochondria were isolated form rat pancreas and directly treated with toxic concentration of atorvastatin (500 µM) in presence of various concentrations hesperidin, vanillic acid, and sinapic acid (1, 10, and 100 µM) separately. Mitochondrial toxicity parameters such as the reactive oxygen species (ROS) formation, succinate dehydrogenases (SDH) activity, mitochondrial swelling, depletion of glutathione (GSH), mitochondrial membrane potential (MMP) collapse, and malondialdehyde (MDA) production were measured. Our findings demonstrated that atorvastatin directly induced mitochondrial toxicity at concentration of 500 μM and higher in pancreatic mitochondria. Except MDA, atorvastatin caused significantly reduction in SDH activity, mitochondrial swelling, ROS formation, depletion of GSH, and collapse of MMP. While, our data showed that all three protective compounds at low concentrations ameliorated atorvastatin-induced mitochondrial dysfunction with the increase of SDH activity, improvement of mitochondrial swelling, MMP collapse and mitochondrial GSH, and reduction of ROS formation. We can conclude that hesperidin, vanillic acid, and sinapic acid can directly reverse the toxic of atorvastatin in rat pancreas isolated mitochondria, which may be beneficial for protection against diabetogenic-induced mitochondrial dysfunction in pancreatic β-cells.
Topics: Animals; Atorvastatin; Mitochondria; Pancreas; Coumaric Acids; Rats; Reactive Oxygen Species; Male; Mitochondrial Swelling; Membrane Potential, Mitochondrial; Vanillic Acid; Hesperidin; Glutathione; Rats, Wistar; Succinate Dehydrogenase; Malondialdehyde
PubMed: 38812443
DOI: 10.1002/ddr.22199 -
Brazilian Journal of Medical and... 2024Adenine nucleotide translocator 4 (Ant4), an ATP/ADP transporter expressed in the early phases of spermatogenesis, plays a crucial role in male fertility. While Ant4...
Adenine nucleotide translocator 4 (Ant4), an ATP/ADP transporter expressed in the early phases of spermatogenesis, plays a crucial role in male fertility. While Ant4 loss causes early arrest of meiosis and increased apoptosis of spermatogenic cells in male mice, its other potential functions in male fertility remain unexplored. Here, we utilized Ant4 knockout mice to delineate the effects of Ant4-deficiency on male reproduction. Our observations demonstrated that Ant4-deficiency led to infertility and impaired testicular development, which was further investigated by evaluating testicular oxidative stress, autophagy, and inflammation. Specifically, the loss of Ant4 led to an imbalance of oxidation and antioxidants. Significant ultrastructural alterations were identified in the testicular tissues of Ant4-deficient mice, including swelling of mitochondria, loss of cristae, and accumulation of autophagosomes. Our results also showed that autophagic flux and AKT-AMPK-mTOR signaling pathway were affected in Ant4-deficient mice. Moreover, Ant4 loss increased the expression of pro-inflammatory factors. Overall, our findings underscored the importance of Ant4 in regulating oxidative stress, autophagy, and inflammation in testicular tissues. Taken together, these insights provided a nuanced understanding of the significance of Ant4 in testicular development.
Topics: Animals; Male; Mice, Knockout; Testis; Oxidative Stress; Mitochondrial ADP, ATP Translocases; Mice; Autophagy; Infertility, Male; Spermatogenesis; Apoptosis; Signal Transduction
PubMed: 38808891
DOI: 10.1590/1414-431X2024e13590 -
Angewandte Chemie (International Ed. in... Jul 2024The inner mitochondrial membrane (IMM) undergoes dynamic morphological changes, which are crucial for the maintenance of mitochondrial functions as well as cell...
The inner mitochondrial membrane (IMM) undergoes dynamic morphological changes, which are crucial for the maintenance of mitochondrial functions as well as cell survival. As the dynamics of the membrane are governed by its lipid components, a fluorescent probe that can sense spatiotemporal alterations in the lipid properties of the IMM over long periods of time is required to understand mitochondrial physiological functions in detail. Herein, we report a red-emissive IMM-labeling reagent with excellent photostability and sensitivity to its environment, which enables the visualization of the IMM ultrastructure using super-resolution microscopy as well as of the lipid heterogeneity based on the fluorescence lifetime at the single mitochondrion level. Combining the probe and fluorescence lifetime imaging microscopy (FLIM) showed that peroxidation of unsaturated lipids in the IMM by reactive oxygen species caused an increase in the membrane order, which took place prior to mitochondrial swelling.
Topics: Fluorescent Dyes; Mitochondrial Membranes; Optical Imaging; Humans; Lipids; Microscopy, Fluorescence; Reactive Oxygen Species; HeLa Cells; Mitochondria
PubMed: 38804831
DOI: 10.1002/anie.202404328 -
Cell Death and Differentiation May 2024Pancreatic ductal adenocarcinoma (PDAC), the most prevalent type of pancreatic cancer, is one of the deadliest forms of cancer with limited therapy options....
Pancreatic ductal adenocarcinoma (PDAC), the most prevalent type of pancreatic cancer, is one of the deadliest forms of cancer with limited therapy options. Overexpression of the heat shock protein 70 (HSP70) is a hallmark of cancer that is strongly associated with aggressive disease and worse clinical outcomes. However, the underlying mechanisms by which HSP70 allows tumor cells to thrive under conditions of continuous stress have not been fully described. Here, we report that PDAC has the highest expression of HSP70 relative to normal tissue across all cancers analyzed. Furthermore, HSP70 expression is associated with tumor grade and is further enhanced in metastatic PDAC. We show that genetic or therapeutic ablation of HSP70 alters mitochondrial subcellular localization, impairs mitochondrial dynamics, and promotes mitochondrial swelling to induce apoptosis. Mechanistically, we find that targeting HSP70 suppresses the PTEN-induced kinase 1 (PINK1) mediated phosphorylation of dynamin-related protein 1 (DRP1). Treatment with the HSP70 inhibitor AP-4-139B was efficacious as a single agent in primary and metastatic mouse models of PDAC. In addition, we demonstrate that HSP70 inhibition promotes the AMP-activated protein kinase (AMPK) mediated phosphorylation of Beclin-1, a key regulator of autophagic flux. Accordingly, we find that the autophagy inhibitor hydroxychloroquine (HCQ) enhances the ability of AP-4-139B to mediate anti-tumor activity in vivo. Collectively, our results suggest that HSP70 is a multi-functional driver of tumorigenesis that orchestrates mitochondrial dynamics and autophagy. Moreover, these findings support the rationale for concurrent inhibition of HSP70 and autophagy as a novel therapeutic approach for HSP70-driven PDAC.
PubMed: 38802657
DOI: 10.1038/s41418-024-01310-9 -
Brain Sciences May 2024Rotenone is a pesticide used in research for its ability to induce changes similar, in vivo and in vitro, to those observed in Parkinson's disease (PD). This includes a...
Rotenone is a pesticide used in research for its ability to induce changes similar, in vivo and in vitro, to those observed in Parkinson's disease (PD). This includes a selective death of dopaminergic neurons in the substantia nigra. Nonetheless, the precise mechanism through which rotenone modifies structure and function of neurons remains unclear. The PC12 cells closely resemble dopamine terminal neurons. This makes it a preferred model for studying the morphology of central dopamine neurons and predicting neurotoxicity. In this paper, we investigated the effects of 0.5 µM rotenone for 24-48 h on PC12 cell viability and ultrastructure (TEM), trying to identify primary and more evident alterations that can be related to neuronal damages similar to that seen in animal PD models. Cell viability decreased after 24 h rotenone treatment, with a further decrease after 48 h. Ultrastructural changes included vacuolar degeneration, mitochondrial mild swelling, decrease in the number of neuropeptide granules, and the loss of cell-to-cell adhesion. These findings are in agreement with previous research suggesting that rotenone, by inhibiting energy production and increasing ROS generation, is responsible for significant alterations of the ultrastructure and cell death of PC12 cells. Our data confirm the link between rotenone exposure, neuronal damage, and changes in dopamine metabolism, suggesting its role in the pathogenesis of PD.
PubMed: 38790454
DOI: 10.3390/brainsci14050476 -
Clinical Hemorheology and... May 2024To investigate the role of Pink1/Parkin-mediated mitochondrial autophagy in exertional heat stroke-induced acute lung injury in rats.
OBJECTIVE
To investigate the role of Pink1/Parkin-mediated mitochondrial autophagy in exertional heat stroke-induced acute lung injury in rats.
METHODS
Sixty SD rats were divided into four groups: normal group (CON group), normal Parkin overexpression group (CON + Parkin group), exertional heat stroke group (EHS group), and exertional heat stroke Parkin overexpression group (EHS + Parkin group). Adeno-associated virus carrying the Parkin gene was intravenously injected into the rats to overexpress Parkin in the lung tissue. An exertional heat stroke rat model was established, and survival curves were plotted. Lung micro-CT was performed, and lung coefficient and pulmonary microvascular permeability were measured.
RESULTS
Compared with the EHS group, the survival rate of rats in the EHS + Parkin overexpression group was significantly increased, lung coefficient and pulmonary microvascular permeability were reduced, and pathological changes such as exudation and consolidation were significantly reduced. The levels of inflammatory factors IL-6, IL-1β, TNF- α, and ROS were significantly decreased; the degree of mitochondrial swelling in type II alveolar epithelial cells was reduced, and no vacuolization was observed. Lung tissue apoptosis was reduced, and the colocalization fluorescence of Pink1 and Parkin, as well as LC3 and Tom20, were increased. The expression of Parkin and LC3-II/LC3-I ratio in lung tissue were both increased, while the expression of P62, Pink1, MFN2, and PTEN-L was decreased.
CONCLUSION
Impairment of Pink1/Parkin-mediated mitochondrial autophagy function is one of the mechanisms of exertional heat stroke-induced acute lung injury in rats. Activation of the Pink1/Parkin pathway can alleviate acute lung injury caused by exertional heat stroke.
PubMed: 38788061
DOI: 10.3233/CH-242100 -
Tropical Medicine and Infectious Disease May 2024Alveolar echinococcosis (AE) stands as a perilous zoonotic affliction caused by the larvae of . There is an imperative need to explore novel therapeutic agents or lead...
Alveolar echinococcosis (AE) stands as a perilous zoonotic affliction caused by the larvae of . There is an imperative need to explore novel therapeutic agents or lead compounds for the treatment of AE. Asparagusic acid, characterized by its low toxicity and possessing antimicrobial, antioxidant, and anti-parasitic attributes, emerges as a promising candidate. The aim of this study was to investigate the in vivo and in vitro efficacy of asparagusic acid against . Morphological observations, scanning electron microscopy, ROS assays, mitochondrial membrane potential assays, and Western blot were used to evaluate the in vitro effects of asparagusic acid on protoscoleces. The effects of asparagusic acid on vesicles were assessed via PGI release, γ-GGT release, and transmission electron microscopy observations. CellTiter-Glo assays, Caspase3 activity assays, flow cytometry, and Western blot were used for an evaluation of the effect of asparaginic acid on the proliferation and apoptosis of germinal cells. The in vivo efficacy of asparagusic acid was evaluated in a murine AE model. Asparagusic acid exhibited a pronounced killing effect on the protoscoleces post-treatment. Following an intervention with asparagusic acid, there was an increase in ROS levels and a decline in mitochondrial membrane potential in the protoscolex. Moreover, asparagusic acid treatment resulted in the upregulation of PGI and γ-GGT release in metacestode vesicles, concomitant with the inhibition of germinal cell viability. Furthermore, asparagusic acid led to an enhanced relative expression of Caspase3 in the culture supernatant of both the protoscoleces and germinal cells, accompanied by an increase in the proportion of apoptotic germinal cells. Notably, asparagusic acid induced an augmentation in Bax and Caspase3 protein expression while reducing Bcl2 protein expression in both the protoscoleces and germinal cells. In vitro cytotoxicity assessments demonstrated the low toxicity of asparagusic acid towards normal human hepatocytes and HFF cells. Additionally, in vivo experiments revealed that asparagusic acid administration at doses of 10 mg/kg and 40 mg/kg significantly reduced metacestode wet weight. A histopathological analysis displayed the disruption of the germinal layer structure within lesions post-asparagusic acid treatment, alongside the preservation of laminated layer structures. Transmission electron microscopy further revealed mitochondrial swelling and heightened cell necrosis subsequent to the asparagusic acid treatment. Furthermore, asparagusic acid promoted Caspase3 and Bax protein expression while decreasing Bcl2 protein expression in perilesional tissues. Subsequently, it inhibited the expression of Ki67, MMP2, and MMP9 proteins in the perilesional tissues and curbed the activation of the PI3K/Akt signaling pathway within the lesion-host microenvironmental tissues. Asparagusic acid demonstrated a pronounced killing effect on , suggesting its potential as a promising therapeutic agent for the management of AE.
PubMed: 38787043
DOI: 10.3390/tropicalmed9050110 -
Physiological Reports May 2024Permeability transition pore (PTP) opening dissipates ion and electron gradients across the internal mitochondrial membrane (IMM), including excess Ca in the...
Permeability transition pore (PTP) opening dissipates ion and electron gradients across the internal mitochondrial membrane (IMM), including excess Ca in the mitochondrial matrix. After opening, immediate PTP closure must follow to prevent outer membrane disruption, loss of cytochrome c, and eventual apoptosis. Flickering, defined as the rapid alternative opening/closing of PTP, has been reported in heart, which undergoes frequent, large variations in Ca. In contrast, in tissues that undergo depolarization events less often, such as the liver, PTP would not need to be as dynamic and thus these tissues would not be as resistant to stress. To evaluate this idea, it was decided to follow the reversibility of the permeability transition (PT) in isolated murine mitochondria from two different tissues: the very dynamic heart, and the liver, which suffers depolarizations less frequently. It was observed that in heart mitochondria PT remained reversible for longer periods and at higher Ca loads than in liver mitochondria. In all cases, Ca uptake was inhibited by ruthenium red and PT was delayed by Cyclosporine A. Characterization of this phenomenon included measuring the rate of oxygen consumption, organelle swelling and Ca uptake and retention. Results strongly suggest that there are tissue-specific differences in PTP physiology, as it resists many more Ca additions before opening in a highly active organ such as the heart than in an organ that seldom suffers Ca loading, such as the liver.
Topics: Animals; Mitochondrial Permeability Transition Pore; Male; Calcium; Mitochondria, Heart; Mitochondria, Liver; Mitochondrial Membrane Transport Proteins; Rats; Rats, Wistar; Oxygen Consumption; Liver; Mitochondrial Swelling; Cyclosporine
PubMed: 38777811
DOI: 10.14814/phy2.16056 -
Toxicology Jun 2024Cadmium (Cd) is a common pollutant with reproductive toxicity. Our previous study revealed that Cd triggered spermatogonia ferroptosis. However, the underlying...
Cadmium (Cd) is a common pollutant with reproductive toxicity. Our previous study revealed that Cd triggered spermatogonia ferroptosis. However, the underlying mechanisms remain unclear. Nuclear receptor coactivator 4 (NCOA4) mediates ferritinophagy and specific degradation of ferritin through lysosomes, resulting in the release of ferrous ions. Excessive autophagy can lead to ferroptosis. This study investigated the role of autophagy in Cd-triggered ferroptosis using GC-1 spermatogonial (spg) cells which exposed to CdCl (5 μM, 10 μM, or 20 μM) for 24 without/with CQ. The cells which transfected with Ncoa4-siRNA were used to explore the role of NCOA4-mediated ferritinophagy in Cd-triggered ferroptosis. The results revealed that Cd caused mitochondrial swelling, rupture of cristae, and vacuolar-like changes. The Cd-treated cells exhibited more autophagosomes. Simultaneously, Cd increased intracellular iron, reactive oxygen species, and malondialdehyde concentrations while decreasing glutathione content and Superoxide Dismutase-2 activity. Moreover, Cd upregulated mRNA levels of ferritinophagy-associated genes (Ncoa4, Lc3b and Fth1), as well as enhanced protein expression of NCOA4, LC3B, and FTH1. While Cd decreased the mRNA and protein expression of p62/SQSTM1. These results showed that Cd caused ferritinophagy and ferroptosis. The use of chloroquine to inhibit autophagy ameliorated Cd-induced iron overload and ferroptosis. Moreover, Ncoa4 knockdown in spermatogonia significantly reduced intracellular iron concentration and alleviated Cd-triggered ferroptosis. In conclusion, our findings demonstrate that Cd activates the ferritinophagy pathway mediated by NCOA4, resulting in iron accumulation through ferritin degradation. This causes oxidative stress, ultimately initiating ferroptosis in spermatogonia. Our results may provide new perspectives and potential strategies for preventing and treating Cd-induced reproductive toxicity.
Topics: Ferroptosis; Nuclear Receptor Coactivators; Male; Spermatogonia; Ferritins; Autophagy; Cadmium; Animals; Cell Line; Mice; Reactive Oxygen Species
PubMed: 38768701
DOI: 10.1016/j.tox.2024.153831