RÉSUMÉ
Liposomes are microspheres produced by placing phospholipids in aqueous solutions. Liposomes have the advantage of being able to encapsulate both hydrophilic and hydrophobic functional substances and are thus important mediators used in cosmetics and pharmaceuticals. It is important for liposomes to have small sizes, uniform particle size distribution, and long-term stability. Previously, liposomes have been prepared using a homo mixer, microfluidizer, and horn and bath types of sonicators. However, it is difficult to produce liposomes with small sizes and uniform particle size distribution using these methods. Therefore, we have developed a focused ultrasound method to produce nano-sized liposomes with better size control. In this study, the liposome solutions were prepared using the focused ultrasound method and conventional methods. The liposome solutions were characterized for their size distribution, stability, and morphology. Results showed that the liposome solution prepared using focused ultrasonic equipment had a uniform particle size distribution with an average size of 113.6 nm and a polydispersity index value of 0.124. Furthermore, the solution showed good stability in dynamic light scattering measurements for 4 d and Turbiscan measurements for 1 week.
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Endothelial progenitor cell (EPC)-based stem cell therapy is a promising therapeutic strategy for vascular diseases. However, continuous in vitro expansion for clinical studies induces the loss of EPC functionality due to aging. In this study, we investigated the effects of StemRegenin-1 (SR-1), an antagonist of aryl hydrocarbon receptor (AhR), on replicative senescence in EPCs. We found that SR-1 maintained the expression of EPC surface markers, including stem cell markers, such as CD34, c-Kit, and CXCR4. Moreover, SR-1 long-term-treated EPCs preserved their characteristics. Subsequently, we demonstrated that SR-1 showed that aging phenotypes were reduced through senescence-associated phenotypes, such as ß-galactosidase activity, SMP30, p21, p53, and senescence-associated secretory phenotype (SASP). SR-1 treatment also increased the proliferation, migration, and tube-forming capacity of senescent EPCs. SR-1 inhibited the AhR-mediated cytochrome P450 (CYP)1A1 expression, reactive-oxygen species (ROS) production, and DNA damage under oxidative stress conditions in EPCs. Furthermore, as a result of CYP1A1-induced ROS inhibition, it was found that accumulated intracellular ROS were decreased in senescent EPCs. Finally, an in vivo Matrigel plug assay demonstrated drastically enhanced blood vessel formation via SR-1-treated EPCs. In summary, our results suggest that SR-1 contributes to the protection of EPCs against cellular senescence.
Sujet(s)
Progéniteurs endothéliaux , Espèces réactives de l'oxygène/métabolisme , Progéniteurs endothéliaux/métabolisme , Récepteurs à hydrocarbure aromatique/métabolisme , Cytochrome P-450 CYP1A1/métabolismeRÉSUMÉ
This study investigated the protective effect of glutathione (GSH), an antioxidant drug, against doxorubicin (DOX)-induced cardiotoxicity. Human cardiac progenitor cells (hCPCs) treated with DOX (250 to 500 nM) showed increased viability and reduced ROS generation and apoptosis with GSH treatment (0.1 to 1 mM) for 24 h. In contrast to the 500 nM DOX group, pERK levels were restored in the group co-treated with GSH and suppression of ERK signaling improved hCPCs' survival. Similarly to the previous results, the reduced potency of hCPCs in the 100 nM DOX group, which did not affect cell viability, was ameliorated by co-treatment with GSH (0.1 to 1 mM). Furthermore, GSH was protected against DOX-induced cardiotoxicity in the in vivo model (DOX 20 mg/kg, GSH 100 mg/kg). These results suggest that GSH is a potential therapeutic strategy for DOX-induced cardiotoxicity, which performs its function via ROS reduction and pERK signal regulation.
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There was an error in representative images of the tube formation in Figure 4b in the original publication [...].
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Anterior gradient protein 2 homolog (AGR2), an endoplasmic reticulum protein, is secreted in the tumor microenvironment. AGR2 is a member of the disulfide isomerase family, is highly expressed in multiple cancers, and promotes cancer metastasis. In this study, we found that etravirine, which is a non-nucleoside reverse transcriptase inhibitor, could induce AGR2 degradation via autophagy. Moreover, etravirine diminished proliferation, migration, and invasion in vitro. Moreover, in an orthotopic xenograft mouse model, the combination of etravirine and paclitaxel significantly suppressed cancer progression and metastasis. This drug may be a promising therapeutic agent for the treatment of ovarian cancer.
Sujet(s)
Mucoprotéines/métabolisme , Nitriles/administration et posologie , Protéines oncogènes/métabolisme , Tumeurs de l'ovaire/traitement médicamenteux , Paclitaxel/administration et posologie , Pyrimidines/administration et posologie , Inhibiteurs de la transcriptase inverse/administration et posologie , Animaux , Lignée cellulaire tumorale , Mouvement cellulaire/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Synergie des médicaments , Femelle , Régulation de l'expression des gènes tumoraux/effets des médicaments et des substances chimiques , Humains , Souris , Mucoprotéines/génétique , Métastase tumorale , Nitriles/pharmacologie , Protéines oncogènes/génétique , Tumeurs de l'ovaire/génétique , Tumeurs de l'ovaire/métabolisme , Paclitaxel/pharmacologie , Protéolyse , Pyrimidines/pharmacologie , Inhibiteurs de la transcriptase inverse/pharmacologie , Tests d'activité antitumorale sur modèle de xénogreffeRÉSUMÉ
Women and men share similar diseases; however, women have unique issues, including gynecologic diseases and diseases related to menstruation, menopause, and post menopause. In recent decades, scientists paid more attention to natural products and their derivatives because of their good tolerability and effectiveness in disease prevention and treatment. Olive oil is an essential component in the Mediterranean diet, a diet well known for its protective impact on human well-being. Investigation of the active components in olive oil, such as oleuropein and hydroxytyrosol, showed positive effects in various diseases. Their effects have been clarified in many suggested mechanisms and have shown promising results in animal and human studies, especially in breast cancer, ovarian cancer, postmenopausal osteoporosis, and other disorders. This review summarizes the current evidence of the role of olives and olive polyphenols in women's health issues and their potential implications in the treatment and prevention of health problems in women.
Sujet(s)
Régime alimentaire sain/méthodes , Olea/composition chimique , Huile d'olive/pharmacologie , Agents protecteurs/pharmacologie , Santé des femmes , Animaux , Régime méditerranéen , Femelle , Humains , Glucosides d'iridoïdes/pharmacologie , Alcool phénéthylique/analogues et dérivés , Alcool phénéthylique/pharmacologie , Huiles végétales/pharmacologie , Polyphénols/pharmacologieRÉSUMÉ
Stem cell-based therapies with clinical applications require millions of cells. Therefore, repeated subculture is essential for cellular expansion, which is often complicated by replicative senescence. Cellular senescence contributes to reduced stem cell regenerative potential as it inhibits stem cell proliferation and differentiation as well as the activation of the senescence-associated secretory phenotype (SASP). In this study, we employed MHY-1685, a novel mammalian target of rapamycin (mTOR) inhibitor, and examined its long-term priming effect on the activities of senile human cardiac stem cells (hCSCs) and the functional benefits of primed hCSCs after transplantation. In vitro experiments showed that the MHY-1685âprimed hCSCs exhibited higher viability in response to oxidative stress and an enhanced proliferation potential compared to that of the unprimed senile hCSCs. Interestingly, priming MHY-1685 enhanced the expression of stemness-related markers in senile hCSCs and provided the differentiation potential of hCSCs into vascular lineages. In vivo experiment with echocardiography showed that transplantation of MHY-1685âprimed hCSCs improved cardiac function than that of the unprimed senile hCSCs at 4 weeks post-MI. In addition, hearts transplanted with MHY-1685-primed hCSCs exhibited significantly lower cardiac fibrosis and higher capillary density than that of the unprimed senile hCSCs. In confocal fluorescence imaging, MHY-1685âprimed hCSCs survived for longer durations than that of the unprimed senile hCSCs and had a higher potential to differentiate into endothelial cells (ECs) within the infarcted hearts. These findings suggest that MHY-1685 can rejuvenate senile hCSCs by modulating autophagy and that as a senescence inhibitor, MHY-1685 can provide opportunities to improve hCSC-based myocardial regeneration.
Sujet(s)
Autophagie , Différenciation cellulaire , Myoblastes cardiaques/cytologie , Myoblastes cardiaques/métabolisme , Régénération , Cellules souches/cytologie , Cellules souches/métabolisme , Autophagie/effets des médicaments et des substances chimiques , Différenciation cellulaire/effets des médicaments et des substances chimiques , Cellules cultivées , Vieillissement de la cellule/effets des médicaments et des substances chimiques , Fibrose , Humains , Mâle , Myocarde/métabolisme , Myocarde/anatomopathologie , Espèces réactives de l'oxygène/métabolisme , Transduction du signal , Transplantation de cellules souches , Sérine-thréonine kinases TOR/métabolismeRÉSUMÉ
Cardiovascular disease (CVD) and its complications are the leading cause of morbidity and mortality in the world. Because of the side effects and incomplete recovery from current therapy, stem cell therapy emerges as a potential therapy for CVD treatment, and endothelial progenitor cell (EPC) is one of the key stem cells used for therapeutic applications. The effect of this therapy required the expansion of EPC function. To enhance the EPC activation, proliferation, and angiogenesis using dronedarone hydrochloride (DH) is the purpose of this study. DH received approval for atrial fibrillation treatment and its cardiovascular protective effects were already reported. In this study, DH significantly increased EPC proliferation, tube formation, migration, and maintained EPCs surface marker expression. In addition, DH treatment up-regulated the phosphorylation of AKT and reduced the reactive oxygen species production. In summary, the cell priming by DH considerably improved the functional activity of EPCs, and the use of which might be a novel strategy for CVD treatment.
RÉSUMÉ
Endothelial progenitor cells (EPCs) are specialized cells in circulating blood, well known for their ability to form new vascular structures. Aging and various ailments such as diabetes, atherosclerosis and cardiovascular disease make EPCs vulnerable to decreasing in number, which affects their migration, proliferation and angiogenesis. Myocardial ischemia is also linked to a reduced number of EPCs and their endothelial functional role, which hinders proper blood circulation to the myocardium. The current study shows that an aminopyrimidine derivative compound (CHIR99021) induces the inhibition of GSK-3ß in cultured late EPCs. GSK-3ß inhibition subsequently inhibits mTOR by blocking the phosphorylation of TSC2 and lysosomal localization of mTOR. Furthermore, suppression of GSK-3ß activity considerably increased lysosomal activation and autophagy. The activation of lysosomes and autophagy by GSK-3ß inhibition not only prevented replicative senescence of the late EPCs but also directed their migration, proliferation and angiogenesis. To conclude, our results demonstrate that lysosome activation and autophagy play a crucial role in blocking the replicative senescence of EPCs and in increasing their endothelial function. Thus, the findings provide an insight towards the treatment of ischemia-associated cardiovascular diseases based on the role of late EPCs.
Sujet(s)
Vieillissement de la cellule/effets des médicaments et des substances chimiques , Progéniteurs endothéliaux/effets des médicaments et des substances chimiques , Glycogen synthase kinase 3 beta/antagonistes et inhibiteurs , Inhibiteurs de protéines kinases/pharmacologie , Pyridines/pharmacologie , Pyrimidines/pharmacologie , Autophagie/effets des médicaments et des substances chimiques , Cellules cultivées , Progéniteurs endothéliaux/cytologie , Progéniteurs endothéliaux/métabolisme , Glycogen synthase kinase 3 beta/métabolisme , Humains , Sérine-thréonine kinases TOR/métabolismeRÉSUMÉ
The mammalian target of rapamycin (mTOR) signaling pathway efficiently regulates the energy state of cells and maintains tissue homeostasis. Dysregulation of the mTOR pathway has been implicated in several human diseases. Rapamycin is a specific inhibitor of mTOR and pharmacological inhibition of mTOR with rapamycin promote cardiac cell generation from the differentiation of mouse and human embryonic stem cells. These studies strongly implicate a role of sustained mTOR activity in the differentiating functions of embryonic stem cells; however, they do not directly address the required effect for sustained mTOR activity in human cardiac progenitor cells. In the present study, we evaluated the effect of mTOR inhibition by rapamycin on the cellular function of human cardiac progenitor cells and discovered that treatment with rapamycin markedly attenuated replicative cell senescence in human cardiac progenitor cells (hCPCs) and promoted their cellular functions. Furthermore, rapamycin not only inhibited mTOR signaling but also influenced signaling pathways, including STAT3 and PIM1, in hCPCs. Therefore, these data reveal a crucial function for rapamycin in senescent hCPCs and provide clinical strategies based on chronic mTOR activity.
Sujet(s)
Vieillissement de la cellule/effets des médicaments et des substances chimiques , Myoblastes cardiaques/effets des médicaments et des substances chimiques , Myoblastes cardiaques/métabolisme , Protéines proto-oncogènes c-pim-1/métabolisme , Facteur de transcription STAT-3/métabolisme , Transduction du signal/effets des médicaments et des substances chimiques , Sérine-thréonine kinases TOR/antagonistes et inhibiteurs , Différenciation cellulaire , Prolifération cellulaire , Cellules cultivées , Biologie informatique/méthodes , Analyse de profil d'expression de gènes , Humains , Sirolimus/pharmacologie , Cellules souches/métabolismeRÉSUMÉ
BACKGROUND: Despite promising advances in stem cell-based therapy, the treatment of ischemic cardiovascular diseases remains a big challenge due to both the insufficient in vivo viability of transplanted cells and poor angiogenic potential of stem cells. The goal of this study was to develop therapeutic human cardiac progenitor cells (hCPCs) for ischemic cardiovascular diseases with a novel M13 peptide carrier. METHOD: In this study, an engineered M13 peptide carrier was successfully generated using a QuikChange Kit. The cellular function of M13 peptide carrier-treated hCPCs was assessed using a tube formation assay and scratch wound healing assay. The in vivo engraftment and cell survival bioactivities of transplanted cells were demonstrated by immunohistochemistry after hCPC transplantation into a myocardial infarction animal model. RESULTS: The engineered M13RGD+SDKP peptide carrier, which expressed RGD peptide on PIII site and SDKP peptide on PVIII site, did not affect morphologic change and proliferation ability in hCPCs. In contrast, hCPCs treated with M13RGD+SDKP showed enhanced angiogenic capacity, including tube formation and migration capacity. Moreover, transplanted hCPCs with M13RGD+SDKP were engrafted into the ischemic region and promoted in vivo cell survival. CONCLUSION: Our present data provides a promising protocol for CPC-based cell therapy via short-term cell priming of hCPCs with engineered M13RGD+SDKP before cell transplantation for treatment of cardiovascular disease.
Sujet(s)
Agents angiogéniques/pharmacologie , Infarctus du myocarde/thérapie , Peptides/métabolisme , Transplantation de cellules souches , Cellules souches/effets des médicaments et des substances chimiques , Animaux , Bactériophage M13/génétique , Maladies cardiovasculaires , Survie cellulaire , Cellules endothéliales , Génie génétique , Humains , Mâle , Souris de lignée BALB C , Myocytes cardiaques/transplantation , Peptides/pharmacologie , Cicatrisation de plaieRÉSUMÉ
The purpose of the present study is to improve the endothelial progenitor cells (EPC) activation, proliferation, and angiogenesis using enzyme-aided extraction of fucoidan by amyloglucosidase (EAEF-AMG). Enzyme-aided extraction of fucoidan by AMG (EAEF-AMG) significantly increased EPC proliferation by reducing the reactive oxygen species (ROS) and decreasing apoptosis. Notably, EAEF-AMG treated EPCs repressed the colocalization of TSC2/LAMP1 and promoted perinuclear localization of mTOR/LAMP1 and mTOR/Rheb. Moreover, EAEF-AMG enhanced EPC functionalities, including tube formation, cell migration, and wound healing via regulation of AKT/Rheb signaling. Our data provided cell priming protocols to enhance therapeutic applications of EPCs using bioactive compounds for the treatment of CVD.
Sujet(s)
Progéniteurs endothéliaux/effets des médicaments et des substances chimiques , Glucan 1,4-alpha-glucosidase/métabolisme , Polyosides/pharmacologie , Protéines proto-oncogènes c-akt/métabolisme , Transduction du signal/effets des médicaments et des substances chimiques , Apoptose/effets des médicaments et des substances chimiques , Mouvement cellulaire/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Cellules cultivées , Progéniteurs endothéliaux/métabolisme , Humains , Protéine de membrane-1 associée au lysosome/métabolisme , Néovascularisation physiologique/effets des médicaments et des substances chimiques , Espèces réactives de l'oxygène/métabolisme , Sérine-thréonine kinases TOR/métabolisme , Protéine-2 du complexe de la sclérose tubéreuse/métabolisme , Cicatrisation de plaie/effets des médicaments et des substances chimiquesRÉSUMÉ
Cardiovascular diseases (CVDs) are a major cause of death worldwide. Due to the prevalence of many side effects and incomplete recovery from pharmacotherapies, stem cell therapy is being targeted for the treatment of CVDs. Among the different types of stem cells, endothelial progenitor cells (EPCs) have great potential. However, cellular replicative senescence decreases the proliferation, migration, and overall function of EPCs. Sirtuin 1 (SIRT1) has been mainly studied in the mammalian aging process. MHY2233 is a potent synthetic SIRT1 activator and a novel antiaging compound. We found that MHY2233 increased the expression of SIRT1, and its deacetylase activity thereby decreased expression of the cellular senescence biomarkers, p53, p16, and p21. In addition, MHY2233 decreased senescence-associated beta-galactosidase- (SA-ß-gal-) positive cells and senescence-associated secretory phenotypes (SASPs), such as the secretion of interleukin- (IL-) 6, IL-8, IL-1α, and IL-1ß. MHY2233 treatment protected senescent EPCs from oxidative stress by decreasing cellular reactive oxygen species (ROS) levels, thus enhancing cell survival and function. The angiogenesis, proliferation, and migration of senescent EPCs were enhanced by MHY2233 treatment. Thus, MHY2233 reduces replicative and oxidative stress-induced senescence in EPCs. Therefore, this novel antiaging compound MHY2233 might be considered a potent therapeutic agent for the treatment of age-associated CVDs.
Sujet(s)
Benzoxazoles/pharmacologie , Progéniteurs endothéliaux/effets des médicaments et des substances chimiques , Sirtuine-1/métabolisme , Vieillissement de la cellule/effets des médicaments et des substances chimiques , Progéniteurs endothéliaux/cytologie , Progéniteurs endothéliaux/métabolisme , Sang foetal/cytologie , Sang foetal/imagerie diagnostique , Sang foetal/métabolisme , Humains , Resvératrol/pharmacologie , Transduction du signal/effets des médicaments et des substances chimiquesRÉSUMÉ
Anterior gradient protein 2 homolog (AGR2) belongs to the disulfide isomerase family of endoplasmic reticulum proteins. Itis overexpressed in several types of solid tumors, including tumors of the prostate, lung, and pancreas. However, the role of AGR2 in breast cancer and the regulatory mechanisms underlying AGR2 protein expressionare not fullyunderstood. We demonstrated that AGR2 levels are increased under hypoxic conditions and in breast cancer tumors. Mechanistically, Twist1 binds to, and activates the AGR2 promoter via an E-box sequence. Under hypoxic conditions, the increased expression of ARG2 is attenuated when Twist1 levels are reduced by shRNA. Conversely, Twist1 overexpression fully reverses decreased AGR2 levels upon HIF-1α knockdown. Notably, AGR2 is required for Twist1-induced proliferation, migration, and invasion of breast cancer cells. Collectively, these findings extend our understanding of AGR2 regulation in breast cancer and may contribute to development of Twist1-AGR2 targeting therapeutics for breast cancer.
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Tumeurs du sein/génétique , Régulation de l'expression des gènes tumoraux , Mucoprotéines/génétique , Protéines nucléaires/génétique , Protéines oncogènes/génétique , Protéine-1 apparentée à Twist/génétique , Tumeurs du sein/anatomopathologie , Lignée cellulaire tumorale , Mouvement cellulaire , Prolifération cellulaire , Femelle , Humains , Adulte d'âge moyen , Régions promotrices (génétique)RÉSUMÉ
Cardiac progenitor cells (CPCs) are resident stem cells present in a small portion of ischemic hearts and function in repairing the damaged heart tissue. Intense oxidative stress impairs cell metabolism thereby decreasing cell viability. Protecting CPCs from undergoing cellular apoptosis during oxidative stress is crucial in optimizing CPC-based therapy. Histochrome (sodium salt of echinochrome A-a common sea urchin pigment) is an antioxidant drug that has been clinically used as a pharmacologic agent for ischemia/reperfusion injury in Russia. However, the mechanistic effect of histochrome on CPCs has never been reported. We investigated the protective effect of histochrome pretreatment on human CPCs (hCPCs) against hydrogen peroxide (H2O2)-induced oxidative stress. Annexin V/7-aminoactinomycin D (7-AAD) assay revealed that histochrome-treated CPCs showed significant protective effects against H2O2-induced cell death. The anti-apoptotic proteins B-cell lymphoma 2 (Bcl-2) and Bcl-xL were significantly upregulated, whereas the pro-apoptotic proteins BCL2-associated X (Bax), H2O2-induced cleaved caspase-3, and the DNA damage marker, phosphorylated histone (γH2A.X) foci, were significantly downregulated upon histochrome treatment of hCPCs in vitro. Further, prolonged incubation with histochrome alleviated the replicative cellular senescence of hCPCs. In conclusion, we report the protective effect of histochrome against oxidative stress and present the use of a potent and bio-safe cell priming agent as a potential therapeutic strategy in patient-derived hCPCs to treat heart disease.
Sujet(s)
Myocytes cardiaques/effets des médicaments et des substances chimiques , Naphtoquinones/pharmacologie , Stress oxydatif/effets des médicaments et des substances chimiques , Cellules souches/effets des médicaments et des substances chimiques , Annexine A5/métabolisme , Apoptose/effets des médicaments et des substances chimiques , Protéines régulatrices de l'apoptose/métabolisme , Caspase-3/métabolisme , Survie cellulaire/effets des médicaments et des substances chimiques , Cellules cultivées , Vieillissement de la cellule/effets des médicaments et des substances chimiques , Altération de l'ADN/effets des médicaments et des substances chimiques , Humains , Peroxyde d'hydrogène/pharmacologie , Myocytes cardiaques/métabolisme , Lésion d'ischémie-reperfusion/induit chimiquement , Lésion d'ischémie-reperfusion/traitement médicamenteux , Lésion d'ischémie-reperfusion/métabolisme , Russie , Protéine Bax/métabolismeRÉSUMÉ
Colorectal cancer is one of the leading causes of cancer-related deaths. Due to relapse after current therapy regimens, cancer stem cells (CSCs) are being studied to target this small tumor-initiating population. Anterior gradient 2 (AGR2), a disulfide isomerase protein, is a well-known pro-oncogenic/metastatic oncogene overexpressed in various tumor tissues, including colon cancer. We found that AGR2 was a novel stem cell marker that was regulated by the canonical Wnt/ß-catenin pathway in colon CSCs. AGR2 was highly co-expressed with surface stem cell markers in spheroidal culture. Silencing of AGR2 resulted in decreased sphere-forming ability and down-regulated expression of stem cell markers, whereas the opposite effects were seen with AGR2 overexpression. Moreover, patients with high ß-catenin and AGR2 expression showed lower overall survival than those with low expression. In conclusion, our study describes a novel role for AGR2 as a stem cell marker that is highly regulated by canonical Wnt/ß-catenin signaling in colorectal cancer.
Sujet(s)
Tumeurs colorectales/métabolisme , Régulation de l'expression des gènes tumoraux , Mucoprotéines/métabolisme , Cellules souches tumorales/métabolisme , Protéines oncogènes/métabolisme , Voie de signalisation Wnt , Lignée cellulaire tumorale , Analyse de profil d'expression de gènes , Extinction de l'expression des gènes , Cellules HCT116 , Cellules HEK293 , Humains , Métastase tumorale , Transduction du signal , Sphéroïdes de cellules , Protéines de type Wingless/métabolisme , bêta-Caténine/métabolismeRÉSUMÉ
Cross talks between the renin-angiotensin system (RAS), sympathetic nervous system, and vascular homeostasis are tightly coordinated in hypertension. Angiotensin II (Ang II), a key factor in RAS, when abnormally activated, affects the number and bioactivity of circulating human endothelial progenitor cells (hEPCs) in hypertensive patients. In this study, we investigated how the augmentation of Ang II regulates adrenergic receptor-mediated signaling and angiogenic bioactivities of hEPCs. Interestingly, the short-term treatment of hEPCs with Ang II drastically attenuated the expression of beta-2 adrenergic receptor (ADRB2), but did not alter the expression of beta-1 adrenergic receptor (ADRB1) and Ang II type 1 receptor (AT1R). EPC functional assay clearly demonstrated that the treatment with ADRB2 agonists significantly increased EPC bioactivities including cell proliferation, migration, and tube formation abilities. However, EPC bioactivities were decreased dramatically when treated with Ang II. Importantly, the attenuation of EPC bioactivities by Ang II was restored by treatment with an AT1R antagonist (telmisartan; TERT). We found that AT1R binds to ADRB2 in physiological conditions, but this binding is significantly decreased in the presence of Ang II. Furthermore, TERT, an Ang II-AT1R interaction blocker, restored the interaction between AT1R and ADRB2, suggesting that Ang II might induce the dysfunction of EPCs via downregulation of ADRB2, and an AT1R blocker could prevent Ang II-mediated ADRB2 depletion in EPCs. Taken together, our report provides novel insights into potential therapeutic approaches for hypertension-related cardiovascular diseases.
RÉSUMÉ
Diabetic cardiomyopathy (DCM) is tightly linked to heart disorders and dysfunction or death of the cardiomyocytes including resident cardiac progenitor cells (CPCs) in diabetic patients. In order to restore loss of function of resident or transplanted CPCs, much research has focused on novel therapeutic strategies including the discovery of novel function-modulating factors such as reactive oxygen species (ROS) scavengers. Here, we developed and defined a novel antioxidant, MHY-1684, for enhancing the angiogenic potential of CPCs against ROS-related DCM. Short-term treatment with MHY-1684 restored ROS-induced CPC cell death. Importantly, MHY-1684 decreased hyperglycemia-induced mitochondrial ROS generation and attenuated hyperglycemia-induced mitochondrial fragmentation. We observed that the activation process of both Drp1 (phosphorylation at the site of Ser616) and Fis-1 is drastically attenuated when exposed to high concentrations of D-glucose with MHY-1684. Interestingly, phosphorylation of Drp1 at the site of Ser637, which is an inhibitory signal for mitochondrial fusion, is restored by MHY-1684 treatment, suggesting that this antioxidant may affect the activation and inhibition of mitochondrial dynamics-related signaling and mitochondrial function in response to ROS stress. In conclusion, our finding of the novel compound, MHY-1684, as an ROS scavenger, might provide an effective therapeutic strategy for CPC-based therapy against diabetic cardiomyopathy.