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International Journal of Nanomedicine 2024To address the problem of suboptimal reactive oxygen species (ROS) production in Radiation therapy (RT) which was resulted from exacerbated tumor hypoxia and the...
PURPOSE
To address the problem of suboptimal reactive oxygen species (ROS) production in Radiation therapy (RT) which was resulted from exacerbated tumor hypoxia and the heterogeneous distribution of radiation sensitizers.
MATERIALS AND METHODS
In this work, a novel nanomedicine, designated as PLGA@IR780-Bi-DTPA (PIBD), was engineered by loading the radiation sensitizer Bi-DTPA and the photothermal agent IR780 onto poly(lactic-co-glycolic acid) (PLGA). This design leverages the tumor-targeting ability of IR780 to ensure selective accumulation of the nanoparticles in tumor cells, particularly within the mitochondria. The effect of the photothermal therapy-enhanced radiation therapy was also examined to assess the alleviation of hypoxia and the enhancement of radiation sensitivity.
RESULTS
The PIBD nanoparticles exhibited strong capacity in mitochondrial targeting and selective tumor accumulation. Upon activation by 808 nm laser irradiation, the nanoparticles effectively alleviated local hypoxia by photothermal effect enhanced blood supplying to improve oxygen content, thereby enhancing the ROS production for effective RT. Comparative studies revealed that PIBD-induced RT significantly outperformed conventional RT in treating hypoxic tumors.
CONCLUSION
This design of tumor-targeting photothermal therapy-enhanced radiation therapy nanomedicine would advance the development of targeted drug delivery system for effective RT regardless of hypoxic microenvironment.
Topics: Animals; Photothermal Therapy; Reactive Oxygen Species; Nanoparticles; Cell Line, Tumor; Humans; Polylactic Acid-Polyglycolic Acid Copolymer; Mice; Indoles; Tumor Hypoxia; Radiation-Sensitizing Agents; Mice, Inbred BALB C; Mitochondria; Neoplasms; Nanomedicine
PubMed: 38946887
DOI: 10.2147/IJN.S450124 -
International Journal of Nanomedicine 2024Mitochondrial oxidative stress is an important factor in cell apoptosis. Cerium oxide nanomaterials show great potential for scavenging free radicals and simulating...
PURPOSE
Mitochondrial oxidative stress is an important factor in cell apoptosis. Cerium oxide nanomaterials show great potential for scavenging free radicals and simulating superoxide dismutase (SOD) and catalase (CAT) activities. To solve the problem of poor targeting of cerium oxide nanomaterials, we designed albumin-cerium oxide nanoclusters (TPP-PCNLs) that target the modification of mitochondria with triphenyl phosphate (TPP). TPP-PCNLs are expected to simulate the activity of superoxide dismutase, continuously remove reactive oxygen species, and play a lasting role in radiation protection.
METHODS
First, cerium dioxide nanoclusters (CNLs), polyethylene glycol cerium dioxide nanoclusters (PCNLs), and TPP-PCNLs were characterized in terms of their morphology and size, ultraviolet spectrum, dispersion stability and cellular uptake, and colocalization Subsequently, the anti-radiation effects of TPP-PCNLs were investigated using in vitro and in vivo experiments including cell viability, apoptosis, comet assays, histopathology, and dose reduction factor (DRF).
RESULTS
TPP-PCNLs exhibited good stability and biocompatibility. In vitro experiments indicated that TPP-PCNLs could not only target mitochondria excellently but also regulate reactive oxygen species (ROS)levels in whole cells. More importantly, TPP-PCNLs improved the integrity and functionality of mitochondria in irradiated L-02 cells, thereby indirectly eliminating the continuous damage to nuclear DNA caused by mitochondrial oxidative stress. TPP-PCNLs are mainly targeted to the liver, spleen, and other extramedullary hematopoietic organs with a radiation dose reduction factor of 1.30. In vivo experiments showed that TPP-PCNLs effectively improved the survival rate, weight change, hematopoietic function of irradiated animals. Western blot experiments have confirmed that TPP-PCNLs play a role in radiation protection by regulating the mitochondrial apoptotic pathway.
CONCLUSION
TPP-PCNLs play a radiologically protective role by targeting extramedullary hematopoietic organ-liver cells and mitochondria to continuously clear ROS.
Topics: Cerium; Animals; Mitochondria; Reactive Oxygen Species; Mice; Apoptosis; Hematopoiesis; Oxidative Stress; Cell Survival; Radiation-Protective Agents; Humans; Radiation Protection; Cell Line
PubMed: 38946882
DOI: 10.2147/IJN.S459607 -
World Journal of Gastroenterology Jun 2024In this editorial, we comment on an article titled "Morphological and biochemical characteristics associated with autophagy in gastrointestinal diseases", which was...
In this editorial, we comment on an article titled "Morphological and biochemical characteristics associated with autophagy in gastrointestinal diseases", which was published in a recent issue of the . We focused on the statement that "autophagy is closely related to the digestion, secretion, and regeneration of gastrointestinal cells". With advancing research, autophagy, and particularly the pivotal role of the macroautophagy in maintaining cellular equilibrium and stress response in the gastrointestinal system, has garnered extensive study. However, the significance of mitophagy, a unique selective autophagy pathway with ubiquitin-dependent and independent variants, should not be overlooked. In recent decades, mitophagy has been shown to be closely related to the occurrence and development of gastrointestinal diseases, especially inflammatory bowel disease, gastric cancer, and colorectal cancer. The interplay between mitophagy and mitochondrial quality control is crucial for elucidating disease mechanisms, as well as for the development of novel treatment strategies. Exploring the pathogenesis behind gastrointestinal diseases and providing individualized and efficient treatment for patients are subjects we have been exploring. This article reviews the potential mechanism of mitophagy in gastrointestinal diseases with the hope of providing new ideas for diagnosis and treatment.
Topics: Humans; Mitophagy; Autophagy; Gastrointestinal Diseases; Mitochondria; Gastrointestinal Tract; Animals
PubMed: 38946875
DOI: 10.3748/wjg.v30.i23.2934 -
Physiological Reports Jul 2024Cancer cachexia is a multifactorial syndrome associated with advanced cancer that contributes to mortality. Cachexia is characterized by loss of body weight and muscle...
Cancer cachexia is a multifactorial syndrome associated with advanced cancer that contributes to mortality. Cachexia is characterized by loss of body weight and muscle atrophy. Increased skeletal muscle mitochondrial reactive oxygen species (ROS) is a contributing factor to loss of muscle mass in cachectic patients. Mice inoculated with Lewis lung carcinoma (LLC) cells lose weight, muscle mass, and have lower muscle sirtuin-1 (sirt1) expression. Nicotinic acid (NA) is a precursor to nicotinamide dinucleotide (NAD+) which is exhausted in cachectic muscle and is a direct activator of sirt1. Mice lost body and muscle weight and exhibited reduced skeletal muscle sirt1 expression after inoculation with LLC cells. C2C12 myotubes treated with LLC-conditioned media (LCM) had lower myotube diameter. We treated C2C12 myotubes with LCM for 24 h with or without NA for 24 h. C2C12 myotubes treated with NA maintained myotube diameter, sirt1 expression, and had lower mitochondrial superoxide. We then used a sirt1-specific small molecule activator SRT1720 to increase sirt1 activity. C2C12 myotubes treated with SRT1720 maintained myotube diameter, prevented loss of sirt1 expression, and attenuated mitochondrial superoxide production. Our data provides evidence that NA may be beneficial in combating cancer cachexia by maintaining sirt1 expression and decreasing mitochondrial superoxide production.
Topics: Animals; Cachexia; Sirtuin 1; Muscle Fibers, Skeletal; Mice; Oxidative Stress; Mice, Inbred C57BL; Carcinoma, Lewis Lung; Male; Heterocyclic Compounds, 4 or More Rings; Mitochondria, Muscle; Cell Line; Niacin; Mitochondria; Reactive Oxygen Species
PubMed: 38946587
DOI: 10.14814/phy2.16103 -
Autoimmunity Dec 2024Chondrocyte viability, apoptosis, and migration are closely related to cartilage injury in osteoarthritis (OA) joints. Exosomes are identified as potential therapeutic...
BACKGROUND
Chondrocyte viability, apoptosis, and migration are closely related to cartilage injury in osteoarthritis (OA) joints. Exosomes are identified as potential therapeutic agents for OA.
OBJECTIVE
This study aimed to investigate the role of exosomes derived from osteocytes in OA, particularly focusing on their effects on cartilage repair and molecular mechanisms.
METHODS
An injury cell model was established by treating chondrocytes with IL-1β. Cartilage repair was evaluated using cell counting kit-8, flow cytometry, scratch test, and Western Blot. Molecular mechanisms were analyzed using quantitative real-time PCR, bioinformatic analysis, and Western Blot. An OA mouse model was established to explore the role of exosomal DLX2 .
RESULTS
Osteocyte-released exosomes promoted cell viability and migration, and inhibited apoptosis and extracellular matrix (ECM) deposition. Moreover, exosomes upregulated DLX2 expression, and knockdown of DLX2 activated the Wnt pathway. Additionally, exosomes attenuated OA in mice by transmitting DLX2.
CONCLUSION
Osteocyte-derived exosomal DLX2 alleviated IL-1β-induced cartilage repair and inactivated the Wnt pathway, thereby alleviating OA progression. The findings suggested that osteocyte-derived exosomes may hold promise as a treatment for OA.
Topics: Exosomes; Animals; Osteoarthritis; Mice; Transcription Factors; Homeodomain Proteins; Osteocytes; Wnt Signaling Pathway; Chondrocytes; Disease Models, Animal; Humans; Interleukin-1beta; Cartilage, Articular; Apoptosis; Cartilage; Male; Cell Movement; Cell Survival
PubMed: 38946534
DOI: 10.1080/08916934.2024.2364686 -
British Journal of Haematology Jun 2024Erythroid cells undergo a highly complex maturation process, resulting in dynamic changes that generate red blood cells (RBCs) highly rich in haemoglobin. The end stages... (Review)
Review
Erythroid cells undergo a highly complex maturation process, resulting in dynamic changes that generate red blood cells (RBCs) highly rich in haemoglobin. The end stages of the erythroid cell maturation process primarily include chromatin condensation and nuclear polarization, followed by nuclear expulsion called enucleation and clearance of mitochondria and other organelles to finally generate mature RBCs. While healthy RBCs are devoid of mitochondria, recent evidence suggests that mitochondria are actively implicated in the processes of erythroid cell maturation, erythroblast enucleation and RBC production. However, the extent of mitochondrial participation that occurs during these ultimate steps is not completely understood. This is specifically important since abnormal RBC retention of mitochondria or mitochondrial DNA contributes to the pathophysiology of sickle cell and other disorders. Here we review some of the key findings so far that elucidate the importance of this process in various aspects of erythroid maturation and RBC production under homeostasis and disease conditions.
PubMed: 38946206
DOI: 10.1111/bjh.19600 -
Journal of Nutritional Science and... 2024The purpose of this study was to examine whether 4 wk of daily ingestion of milk fat globule membrane (MFGM) combined with exercise training improves physical... (Randomized Controlled Trial)
Randomized Controlled Trial
Effects of Milk Fat Globule Membrane Supplementation Following Exercise Training on Physical Performance in Healthy Young Adults: A Randomized Double-Blind, Placebo-Controlled Pilot Trial.
The purpose of this study was to examine whether 4 wk of daily ingestion of milk fat globule membrane (MFGM) combined with exercise training improves physical performance-muscle strength, agility and muscle power-in healthy young adults. The study was designed as a randomized, double-blind, and placebo-controlled trial. Twenty healthy young adults received either an MFGM powder containing 1.6 g of fat and 160 mg of sphingomyelin or an isocaloric placebo powder daily throughout 4 wk of power or agility training. Physical performance tests and body composition measurements were conducted before and after the 4-wk intervention. Ingestion of MFGM did not affect isometric or isokinetic muscle strength, but it was associated with a greater increase in vertical jump peak power compared with placebo. There were no significant changes in body weight or lean body mass during the intervention period in either group, and no significant differences between groups. We conclude that daily MFGM supplementation combined with exercise training has the potential to improve physical performance in young adults; however, further studies with larger sample sizes should be conducted to obtain more evidence supporting achievement of improved physical performance through MFGM supplementation.
Topics: Humans; Double-Blind Method; Glycolipids; Lipid Droplets; Glycoproteins; Male; Young Adult; Female; Dietary Supplements; Muscle Strength; Body Composition; Exercise; Pilot Projects; Adult; Physical Functional Performance; Body Weight; Sphingomyelins; Muscle, Skeletal
PubMed: 38945893
DOI: 10.3177/jnsv.70.273 -
The Journal of Toxicological Sciences 2024Dihydropyrazines (DHPs) are formed by non-enzymatic glycation reactions in vivo and in food. We recently reported that 3-hydro-2,2,5,6-tetramethylpyrazine (DHP-3), which...
Dihydropyrazines (DHPs) are formed by non-enzymatic glycation reactions in vivo and in food. We recently reported that 3-hydro-2,2,5,6-tetramethylpyrazine (DHP-3), which is a methyl-substituted DHP, caused severe oxidative stress and cytotoxicity. However, the molecular mechanisms underlying the cytotoxic pathways of the DHP response remain elusive. Because oxidative stress induces endoplasmic reticulum (ER) stress and autophagy, we investigated the ability of DHP-3 to modulate the ER stress and autophagy pathways. DHP-3 activated the ER stress pathway by increasing inositol-requiring enzyme 1 (IRE1) and PKR-like ER kinase (PERK) phosphorylation and transcription factor 6 (ATF6) expression. Moreover, DHP-3 increased the expression of activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP), which are downstream targets of PERK. In addition, DHP-3 inhibited the autophagy pathway by increasing the accumulation of microtubule-associated protein 1 light chain 3 alpha-phosphatidylethanolamine conjugate (LC3-II) and p62/sequestosome 1 (p62), while decreasing autophagic flux. Taken together, these results indicate that DHP-3 activates the ER stress pathway and inhibits the autophagy pathway, suggesting that the resulting removal of damaged organelles is inadequate.
Topics: Humans; Autophagy; Endoplasmic Reticulum Stress; Pyrazines; Hep G2 Cells; Activating Transcription Factor 4; eIF-2 Kinase; Activating Transcription Factor 6; Protein Serine-Threonine Kinases; Transcription Factor CHOP; Endoribonucleases; Phosphorylation; Carcinoma, Hepatocellular; Liver Neoplasms; Oxidative Stress; Sequestosome-1 Protein; Signal Transduction; Microtubule-Associated Proteins
PubMed: 38945842
DOI: 10.2131/jts.49.313 -
Trends in Biochemical Sciences Jun 2024Migrasomes, newly identified organelles, play crucial roles in intercellular communication, contributing to organ development and angiogenesis. These vesicles, forming... (Review)
Review
Migrasomes, newly identified organelles, play crucial roles in intercellular communication, contributing to organ development and angiogenesis. These vesicles, forming on retraction fibers of migrating cells, showcase a sophisticated architecture. Recent research reveals that migrasome biogenesis is a complicated and highly regulated process. This review summarizes the mechanisms governing migrasome formation, proposing a model in which biogenesis is understood through the lens of membrane microdomain assembly. It underscores the critical interplay between biochemistry and biophysics. The biogenesis unfolds in three distinct stages: nucleation, maturation, and expansion, each characterized by unique morphological, biochemical, and biophysical features. We also explore the broader implications of migrasome research in membrane biology and outline key unanswered questions that represent important directions for future investigation.
PubMed: 38945731
DOI: 10.1016/j.tibs.2024.06.004 -
Physiologia Plantarum 2024Chlorophyll (Chl) plays a crucial role in photosynthesis, functioning as a photosensitizer. As an integral component of this process, energy absorbed by this pigment is...
Chlorophyll (Chl) plays a crucial role in photosynthesis, functioning as a photosensitizer. As an integral component of this process, energy absorbed by this pigment is partly emitted as red fluorescence. This signal can be readily imaged by fluorescence microscopy and provides a visualization of photosynthetic activity. However, due to limited resolution, signals cannot be assigned to specific subcellular/organellar membrane structures. By correlating fluorescence micrographs with transmission electron microscopy, researchers can identify sub-cellular compartments and membranes, enabling the monitoring of Chl distribution within thylakoid membrane substructures in cyanobacteria, algae, and higher plant single cells. Here, we describe a simple and effective protocol for correlative light-electron microscopy (CLEM) based on the autofluorescence of Chl and demonstrate its application to selected photosynthetic model organisms. Our findings illustrate the potential of this technique to identify areas of high Chl concentration and photochemical activity, such as grana regions in vascular plants, by mapping stacked thylakoids.
Topics: Thylakoids; Chlorophyll; Photosynthesis; Microscopy, Fluorescence; Microscopy, Electron, Transmission
PubMed: 38945684
DOI: 10.1111/ppl.14417