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1.
Free Radic Biol Med ; 220: 67-77, 2024 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-38657755

RÉSUMÉ

Sarcopenia is characterized by loss of muscle strength and muscle mass with aging. The growing number of sarcopenia patients as a result of the aging population has no viable treatment. Exercise maintains muscle strength and mass by increasing peroxisome growth factor activating receptor γ-conjugating factor-1α (PGC-1α) and Akt signaling in skeletal muscle. The present study focused on the carbon monoxide (CO), endogenous activator of PGC-1α and Akt, and investigated the therapeutic potential of CO-loaded red blood cells (CO-RBCs), which is bioinspired from in vivo CO delivery system, as an exercise mimetic for the treatment of sarcopenia. Treatment of C2C12 myoblasts with the CO-donor increased the protein levels of PGC-1α which enhanced mitochondrial biogenesis and energy production. The CO-donor treatment also activated Akt, indicating that CO promotes muscle synthesis. CO levels were significantly elevated in the skeletal muscle of normal mice after intravenous administration of CO-RBCs. Furthermore, CO-RBCs restored the mRNA expression levels of PGC-1α in the skeletal muscle of two experimental sarcopenia mouse models, denervated (Den) and hindlimb unloading (HU) models. CO-RBCs also restored muscle mass in Den mice by activating Akt signaling and suppressing the muscle atrophy factors myostatin and atrogin-1, and oxidative stress. Treadmill tests further showed that the reduced running distance in HU mice was significantly restored by CO-RBC administration. These findings suggest that CO-RBCs have potential as an exercise mimetic for sarcopenia treatment.


Sujet(s)
Monoxyde de carbone , Muscles squelettiques , Coactivateur 1-alpha du récepteur gamma activé par les proliférateurs de peroxysomes , Sarcopénie , Sarcopénie/traitement médicamenteux , Sarcopénie/métabolisme , Sarcopénie/thérapie , Sarcopénie/anatomopathologie , Animaux , Souris , Monoxyde de carbone/métabolisme , Monoxyde de carbone/pharmacologie , Coactivateur 1-alpha du récepteur gamma activé par les proliférateurs de peroxysomes/métabolisme , Coactivateur 1-alpha du récepteur gamma activé par les proliférateurs de peroxysomes/génétique , Muscles squelettiques/métabolisme , Muscles squelettiques/effets des médicaments et des substances chimiques , Muscles squelettiques/anatomopathologie , Protéines proto-oncogènes c-akt/métabolisme , Humains , Thérapie cellulaire et tissulaire/méthodes , Transduction du signal/effets des médicaments et des substances chimiques , Mâle , Modèles animaux de maladie humaine , Myoblastes/métabolisme , Myoblastes/effets des médicaments et des substances chimiques , Conditionnement physique d'animal , Souris de lignée C57BL , Lignée cellulaire , Protéines du muscle/métabolisme , Protéines du muscle/génétique
2.
Antioxidants (Basel) ; 12(9)2023 Sep 01.
Article de Anglais | MEDLINE | ID: mdl-37760008

RÉSUMÉ

Cisplatin-induced acute kidney injury (AKI) is an important factor that limits the clinical use of this drug for the treatment of malignancies. Oxidative stress and inflammation are considered to be the main causes of not only cisplatin-induced death of cancer cells but also cisplatin-induced AKI. Therefore, developing agents that exert antioxidant and anti-inflammatory effects without weakening the anti-tumor effects of cisplatin is highly desirable. Carbon monoxide (CO) has recently attracted interest due to its antioxidant, anti-inflammatory, and anti-tumor properties. Herein, we report that CO-loaded red blood cell (CO-RBC) exerts renoprotective effects on cisplatin-induced AKI. Cisplatin treatment was found to reduce cell viability in proximal tubular cells via oxidative stress and inflammation. Cisplatin-induced cytotoxicity, however, was suppressed by the CO-RBC treatment. The intraperitoneal administration of cisplatin caused an elevation in the blood urea nitrogen and serum creatinine levels. The administration of CO-RBC significantly suppressed these elevations. Furthermore, the administration of CO-RBC also reduced the deterioration of renal histology and tubular cell injury through its antioxidant and anti-inflammatory effects in cisplatin-induced AKI mice. Thus, our data suggest that CO-RBC has the potential to substantially prevent the onset of cisplatin-induced AKI, which, in turn, may improve the usefulness of cisplatin-based chemotherapy.

3.
Biosci Biotechnol Biochem ; 86(11): 1515-1523, 2022 Oct 20.
Article de Anglais | MEDLINE | ID: mdl-36099872

RÉSUMÉ

Shade cultivation of tea plants (Camellia sinensis L.) is employed for the production of high-quality green tea which increases the content of chlorophylls and free amino acids, including theanine. However, shaded tea plants suffer from photooxidative stress caused by sudden exposure to high light (HL) when the shade is removed. In this study, we tried to acclimatize shaded tea plants to light prior to shade removal to alleviate HL-induced stress. Acclimated tea plants showed milder photoinhibition in response to HL exposure than the shaded plants without acclimation. Moreover, there were no large differences in the total chlorophylls and free amino acids (including theanine) content between acclimated and non-acclimated plants. These results indicate that acclimation of shaded tea plants can alleviate subsequent HL stress without causing large changes in the content of chemical components associated with tea quality.


Sujet(s)
Camellia sinensis , Camellia sinensis/composition chimique , Feuilles de plante/composition chimique , Thé/composition chimique , Chlorophylle/métabolisme , Acclimatation , Acides aminés/métabolisme
4.
Redox Biol ; 54: 102371, 2022 08.
Article de Anglais | MEDLINE | ID: mdl-35763935

RÉSUMÉ

Renal ischemia-reperfusion (IR)-induced tissue hypoxia causes impaired energy metabolism and oxidative stress. These conditions lead to tubular cell damage, which is a cause of acute kidney injury (AKI) and AKI to chronic kidney disease (CKD). Three key molecules, i.e., hypoxia-inducible factor-1α (HIF-1α), AMP-activated protein kinase (AMPK), and nuclear factor E2-related factor 2 (Nrf2), have the potential to protect tubular cells from these disorders. Although carbon monoxide (CO) can comprehensively induce these three molecules via the action of mitochondrial reactive oxygen species (mtROS), the issue of whether CO induces these molecules in tubular cells remains unclear. Herein, we report that CO-enriched red blood cells (CO-RBC) cell therapy, the inspiration for which is the in vivo CO delivery system, exerts a renoprotective effect on hypoxia-induced tubular cell damage via the upregulation of the above molecules. Experiments using a mitochondria-specific antioxidant provide evidence to show that CO-driven mtROS partially contributes to the upregulation of the aforementioned molecules in tubular cells. CO-RBC ameliorates the pathological conditions of IR-induced AKI model mice via activation of these molecules. CO-RBC also prevents renal fibrosis via the suppression of epithelial mesenchymal transition and transforming growth factor-ß1 secretion in an IR-induced AKI to CKD model mice. In conclusion, our results confirm that the bioinspired CO delivery system prevents the pathological conditions of both AKI and AKI to CKD via the amelioration of hypoxia inducible tubular cell damage, thereby making it an effective cell therapy for treating the progression to CKD.


Sujet(s)
Atteinte rénale aigüe , Insuffisance rénale chronique , Lésion d'ischémie-reperfusion , Atteinte rénale aigüe/métabolisme , Animaux , Monoxyde de carbone/métabolisme , Monoxyde de carbone/pharmacologie , Hypoxie/métabolisme , Rein/métabolisme , Souris , Insuffisance rénale chronique/métabolisme , Lésion d'ischémie-reperfusion/métabolisme
5.
J Control Release ; 341: 457-474, 2022 01.
Article de Anglais | MEDLINE | ID: mdl-34856227

RÉSUMÉ

Kupffer cells are a key source of reactive oxygen species (ROS) and are implicated in the development of steatohepatitis and fibrosis in nonalcoholic steatohepatitis (NASH). We recently developed a polythiolated and mannosylated human serum albumin (SH-Man-HSA), a nano-antioxidant that targets Kupffer cells, in which the mannosyl units on albumin allows their specific uptake by Kupffer cells via the mannose receptor C type 1 (MRC1), and in which the polythiolation confers antioxidant activity. The aim of this study was to investigate the therapeutic potential of SH-Man-HSA in NASH model mice. In livers from mice and/or patients with NASH, we observed a reduced blood flow in the liver lobes and the down-regulation in MRC1 expression in Kupffer cells, and SH-Man-HSA alone failed to improve the pathological phenotype in NASH. However, the administration of a nitric oxide (NO) donor restored hepatic blood flow and increased the expression of the mannose receptor C type 2 (MRC2) instead of MRC1. Consequently, treatment with a combination of SH-Man-HSA and an NO donor improved oxidative stress-associated pathology. Finally, we developed a hybrid type of nano-antioxidant (SNO-Man-HSA) via the S-nitrosation of SH-Man-HSA. This nanomedicine efficiently delivered both NO and thiol groups to the liver, with a hepatoprotective effect that was comparable to the combination therapy of SH-Man-HSA and an NO donor. These findings suggest that SNO-Man-HSA has the potential for functioning as a novel nano-therapy for the treatment of NASH.


Sujet(s)
Stéatose hépatique non alcoolique , Animaux , Antioxydants/usage thérapeutique , Humains , Cellules de Küpffer/métabolisme , Souris , Monoxyde d'azote/métabolisme , Stéatose hépatique non alcoolique/traitement médicamenteux , Stéatose hépatique non alcoolique/métabolisme
6.
EBioMedicine ; 66: 103275, 2021 Apr.
Article de Anglais | MEDLINE | ID: mdl-33745882

RÉSUMÉ

BACKGROUND: Assistive automatic seizure detection can empower human annotators to shorten patient monitoring data review times. We present a proof-of-concept for a seizure detection system that is sensitive, automated, patient-specific, and tunable to maximise sensitivity while minimizing human annotation times. The system uses custom data preparation methods, deep learning analytics and electroencephalography (EEG) data. METHODS: Scalp EEG data of 365 patients containing 171,745 s ictal and 2,185,864 s interictal samples obtained from clinical monitoring systems were analysed as part of a crowdsourced artificial intelligence (AI) challenge. Participants were tasked to develop an ictal/interictal classifier with high sensitivity and low false alarm rates. We built a challenge platform that prevented participants from downloading or directly accessing the data while allowing crowdsourced model development. FINDINGS: The automatic detection system achieved tunable sensitivities between 75.00% and 91.60% allowing a reduction in the amount of raw EEG data to be reviewed by a human annotator by factors between 142x, and 22x respectively. The algorithm enables instantaneous reviewer-managed optimization of the balance between sensitivity and the amount of raw EEG data to be reviewed. INTERPRETATION: This study demonstrates the utility of deep learning for patient-specific seizure detection in EEG data. Furthermore, deep learning in combination with a human reviewer can provide the basis for an assistive data labelling system lowering the time of manual review while maintaining human expert annotation performance. FUNDING: IBM employed all IBM Research authors. Temple University employed all Temple University authors. The Icahn School of Medicine at Mount Sinai employed Eren Ahsen. The corresponding authors Stefan Harrer and Gustavo Stolovitzky declare that they had full access to all the data in the study and that they had final responsibility for the decision to submit for publication.


Sujet(s)
Intelligence artificielle , Encéphale/physiopathologie , Électroencéphalographie , Neurologues , Crises épileptiques/diagnostic , Algorithmes , Analyse de données , Apprentissage profond , Électroencéphalographie/méthodes , Électroencéphalographie/normes , Épilepsie/diagnostic , Humains , Reproductibilité des résultats
7.
J Pharmacol Exp Ther ; 372(3): 355-365, 2020 03.
Article de Anglais | MEDLINE | ID: mdl-31924689

RÉSUMÉ

Many victims, after being extricated from a collapsed building as the result of a disaster, suffer from disaster nephrology, a term that is referred to as the crush syndrome (CS). Recommended treatments, which include dialysis or the continuous administration of massive amounts of fluid are not usually easy in cases of such mass natural disasters. In the present study, we examined the therapeutic performance of a biomimetic carbon monoxide (CO) delivery system, CO-enriched red blood cells (CO-RBCs), on experimental animal models of an acute kidney injury (AKI) induced by traumatic and nontraumatic rhabdomyolysis, including CS and rhabdomyolysis with massive hemorrhage shock. A single CO-RBC treatment was found to effectively suppress the pathogenesis of AKI with the mortality in these model rats being improved. In addition, in further studies using glycerol-induced rhabdomyolysis model rats, the pathogenesis of which is similar to that for the CS, AKI and mortality were also reduced as the result of a CO-RBC treatment. Furthermore, CO-RBCs were found to have renoprotective effects via the suppression of subsequent heme protein-associated renal oxidative injury; the oxidation of myoglobin in the kidneys, the generation of reactive oxygen species by free heme produced from degraded-cytochrome P450 and hemoglobin-associated renal injury. Because CO-RBCs can be prepared and used at both hospitals and at a disaster site, these findings suggest that CO-RBCs have the potential for use as a novel cell therapy against both nontraumatic and traumatic rhabdomyolysis including CS-induced AKI. SIGNIFICANCE STATEMENT: After mass natural and man-made disasters, people who are trapped in collapsed buildings are in danger of acute kidney injury (AKI), including crush syndrome (CS)-related AKI. This paper reports that carbon monoxide-enriched red blood cells (CO-RBCs), which can be prepared at both hospitals and disaster sites, dramatically suppressed the pathogenesis of CS-related AKI, thus improving mortality via suppressing heme protein-associated renal injuries. CO-RBCs have the potential for serving as a practical therapeutic agent against disaster nephrology associated with the CS.


Sujet(s)
Atteinte rénale aigüe/traitement médicamenteux , Monoxyde de carbone/usage thérapeutique , Syndrome d'écrasement/complications , Érythrocytes/composition chimique , Rein/effets des médicaments et des substances chimiques , Rhabdomyolyse/complications , Atteinte rénale aigüe/étiologie , Animaux , Apoptose/effets des médicaments et des substances chimiques , Monoxyde de carbone/administration et posologie , Modèles animaux de maladie humaine , Systèmes de délivrance de médicaments , Rein/métabolisme , Rein/anatomopathologie , Cellules LLC-PK1 , Stress oxydatif/effets des médicaments et des substances chimiques , Rat Sprague-Dawley , Analyse de survie , Suidae
8.
Drug Deliv ; 25(1): 1266-1274, 2018 Nov.
Article de Anglais | MEDLINE | ID: mdl-29847178

RÉSUMÉ

Macrophages play a central role in various inflammatory disorders and are broadly divided into two subpopulations, M1 and M2 macrophage. In the healing process in acute inflammatory disorders, shifting the production of M1 macrophages to M2 macrophages is desirable, because M1 macrophages secrete pro-inflammatory cytokines, whilst the M2 variety secrete anti-inflammatory cytokines. Previous findings indicate that when macrophages are treated with carbon monoxide (CO), the secretion of anti-inflammatory cytokine is increased and the expression of pro-inflammatory cytokines is inhibited, indicating that CO may have a potential to modulate the production of macrophages toward the M2-like phenotype. In this study, we examined the issue of whether CO targeting macrophages using a nanotechnology-based CO donor, namely CO-bound hemoglobin vesicles (CO-HbV), modulates their polarization and show therapeutic effects against inflammatory disorders. The results showed that the CO-HbV treatment polarized a macrophage cell line toward an M2-like phenotype. Furthermore, in an in vivo study using acute pancreatitis model mice as a model of an inflammatory disease, a CO-HbV treatment also tended to polarize macrophages toward an M2-like phenotype and inhibited neutrophil infiltration in the pancreas, resulting in a significant inflammation. In addition to the suppression of acute pancreatitis, CO-HbV diminished a subsequent pancreatitis-associated acute lung injury. This could be due to the inhibition of the systemic inflammation, neutrophil infiltration in the lungs and the production of HMGB-1. These findings suggest that CO-HbV exerts superior anti-inflammatory effects against inflammatory disorders via the regulation of macrophage and neutrophil activity.


Sujet(s)
Anti-inflammatoires/administration et posologie , Anti-inflammatoires/composition chimique , Monoxyde de carbone/composition chimique , Hémoglobines/composition chimique , Macrophages/effets des médicaments et des substances chimiques , Granulocytes neutrophiles/effets des médicaments et des substances chimiques , Pancréatite/traitement médicamenteux , Animaux , Biomimétique/méthodes , Lignée cellulaire , Cytokines/métabolisme , Modèles animaux de maladie humaine , Inflammation/traitement médicamenteux , Inflammation/métabolisme , Macrophages/métabolisme , Mâle , Souris , Souris de lignée C57BL , Granulocytes neutrophiles/métabolisme , Pancréas/effets des médicaments et des substances chimiques , Pancréas/métabolisme , Pancréatite/métabolisme , Phénotype , Cellules RAW 264.7
9.
Drug Deliv ; 25(1): 1067-1077, 2018 Nov.
Article de Anglais | MEDLINE | ID: mdl-29688069

RÉSUMÉ

Because of its multifaceted anti-inflammatory and immunomodulatory effects, delivering type-I interferon to Kupffer cells has the potential to function as a novel type of therapy for the treatment of various types of hepatitis. We report herein on the preparation of a Kupffer cell targeting type-I interferon, an albumin-IFNα2b fusion protein that contains highly mannosylated N-linked oligosaccharide chains, Man-HSA(D494N)-IFNα2b, attached by combining albumin fusion technology and site-directed mutagenesis. The presence of this unique oligosaccharide permits the protein to be efficiently, rapidly and preferentially distributed to Kupffer cells. Likewise IFNα2b, Man-HSA(D494N)-IFNα2b caused a significant induction in the mRNA levels of IL-10, IL-1Ra, PD-L1 in RAW264.7 cells and mouse isolated Kupffer cells, and these inductions were largely inhibited by blocking the interferon receptor. These data indicate that Man-HSA(D494N)-IFNα2b retained the biological activities of type-I interferon. Man-HSA(D494N)-IFNα2b significantly inhibited liver injury in Concanavalin A (Con-A)-induced hepatitis model mice, and consequently improved their survival rate. Moreover, the post-administration of Man-HSA(D494N)-IFNα2b at 2 h after the Con-A challenge also exerted hepato-protective effects. In conclusion, this proof-of-concept study demonstrates the therapeutic effectiveness and utility of Kupffer cell targeting type-I interferon against hepatitis via its anti-inflammatory and immunomodulatory actions.


Sujet(s)
Anti-inflammatoires/pharmacologie , Hépatite/traitement médicamenteux , Facteurs immunologiques/pharmacologie , Interféron de type I/métabolisme , Cellules de Küpffer/effets des médicaments et des substances chimiques , Cellules de Küpffer/métabolisme , Animaux , Antigène CD274/métabolisme , Lignée cellulaire , Hépatite/métabolisme , Humains , Interféron alpha-2 , Interféron alpha/métabolisme , Antagoniste du récepteur à l'interleukine-1/métabolisme , Interleukine-10/métabolisme , Foie/effets des médicaments et des substances chimiques , Foie/métabolisme , Mâle , Mannose/métabolisme , Souris , Souris de lignée C57BL , Souris de lignée ICR , Cellules RAW 264.7 , Protéines recombinantes/métabolisme , Sérumalbumine/métabolisme
10.
Biopsychosoc Med ; 8: 14, 2014.
Article de Anglais | MEDLINE | ID: mdl-25061475

RÉSUMÉ

This research, conducted in 1998 and 2008, uses go/no-go data to investigate the fundamentals of cognitive functioning in the inhibitory control ability of Japanese children. 844 subjects from kindergarten to junior high school participated in go/no-go task experiments. Performance of go/no-go tasks, which are frequently used to investigate response inhibition, measures a variety of cognitive components besides response inhibition. With normal brain development, the ability to inhibit responses improves substantially in adolescence. An increase over time in the error rate during the go/no-go tasks of subjects of the same age indicates that these processes are not functioning properly. Comparisons between the 1998 and 2008 data revealed several differences in error rates. In 2008, there were increases in the number of errors in groups from each age range. The comparison also revealed that overall error rates peaked at later ages in the 2008 subjects. Taken together, these results show changing conditions in the inhibitory function of the prefrontal cortex. However, the reason for these changing conditions remains unclear. While a lifestyle questionnaire revealed several differences in factors such as bedtimes and hours spent watching TV, analysis did not reveal a significant correlation.

11.
J Vet Med Sci ; 73(10): 1351-4, 2011 Oct.
Article de Anglais | MEDLINE | ID: mdl-21646747

RÉSUMÉ

Hyperbaric air therapy (HBA) is a treatment in which an animal is exposed to air pressurized to about 1.3 atmosphere absolute (ATA). Although HBA has already been administered to humans in medical applications, it has not been reported in clinical veterinary medicine. Therefore, we aimed to determine a safe protocol for dogs. To elucidate oxygen dynamics during HBA, we measured partial pressure of arterial oxygen, oxygen saturation of tissue, and partial pressure of transcutaneous oxygen in dogs. HBA could be performed safely with a protocol of pressurizing speed up to 0.1 ATA/min, maximum chamber pressure of up to 1.3 ATA, and pressure duration of around 45 min per treatment. Under these conditions, tissue was adequately oxygenated during and after treatment.


Sujet(s)
Chiens/sang , Oxygénation hyperbare/médecine vétérinaire , Oxygène/sang , Animaux , Femelle , Oxygénation hyperbare/méthodes , Oxymétrie/médecine vétérinaire
12.
Neuroimage ; 50(4): 1702-10, 2010 May 01.
Article de Anglais | MEDLINE | ID: mdl-20006719

RÉSUMÉ

A growing number of human studies have reported the beneficial influences of acute as well as chronic exercise on cognitive functions. However, neuroimaging investigations into the neural substrates of the effects of acute exercise have yet to be performed. Using multichannel functional near-infrared spectroscopy (fNIRS), we sought cortical activation related to changes in the Stroop interference test, elicited by an acute bout of moderate exercise, in healthy volunteers (N=20). The compactness and portability of fNIRS allowed on-site cortical examination in a laboratory with a cycle ergometer, enabling strict control of the exercise intensity of each subject by assessing their peak oxygen intake (VO2peak). We defined moderate exercise intensity as 50% of a subject's peak oxygen uptake (50%VO2peak). An acute bout of moderate exercise caused significant improvement of cognitive performance reflecting Stroop interference as measured by reaction time. Consistent with previous functional neuroimaging studies, we detected brain activation due to Stroop interference (incongruent minus neutral) in the lateral prefrontal cortices in both hemispheres. This Stroop-interference-related activation was significantly enhanced in the left dorsolateral prefrontal cortex due to the acute bout of moderate exercise. The enhanced activation significantly coincided with the improved cognitive performance. This suggests that the left dorsolateral prefrontal cortex is likely the neural substrate for the improved Stroop performance elicited by an acute bout of moderate exercise. fNIRS, which allows physiological monitoring and functional neuroimaging to be combined, proved to be an effective tool for examining the cognitive effects of exercise.


Sujet(s)
Cognition/physiologie , Exercice physique/physiologie , Cortex préfrontal/physiologie , Adulte , Épreuve d'effort , Femelle , Latéralité fonctionnelle , Humains , Mâle , Consommation d'oxygène , Projets pilotes , Temps de réaction , Spectroscopie proche infrarouge , Test de Stroop , Jeune adulte
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