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1.
Hepatology ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976867

RESUMO

BACKGROUND AIMS: Studies have shown that blocking the PD-1/PD-L1 pathway may lead to a potential cure for HBV infections. ASC22 (Envafolimab) is a humanized, single-domain PD-L1 antibody administered subcutaneously. This study aimed to evaluate the efficacy and safety of ASC22 in virally suppressed chronic hepatitis B (CHB) patients on nucleos(t)ide analogs (NAs). APPROACH AND RESULTS: This randomized, single-blind, phase IIb trial enrolled CHB patients in two cohorts for a 24-week treatment with ASC22 or placebo (PBO) once every 2 weeks and 24-week follow-up. In total, 60, 59, and 30 patients were treated with 1.0, 2.5 mg/kg ASC22 and PBO, respectively. The mean HBsAg changes from baseline at week 24 and 24 week follow-up periods were -0.309 (p<0.001) and -0.272 (p<0.023) log10 IU/mL in the 1.0 mg/kg ASC22 group, -0.231 (p=0.007) and -0.205 (p=0.12) log10 IU/mL in the 2.5 mg/kg ASC22 group, and-0.003 and -0.063 log10 IU/mL in the PBO group, respectively (ITT population). Three out of ten patients with baseline HBsAg levels ≤100 IU/mL in the 1.0 mg/kg group obtained on-treatment HBsAg loss. Most AEs were mild (97.9%). There were no study drug-related serious AEs in the 1.0 mg/kg ASC22 group. CONCLUSIONS: Subcutaneous administration of 1.0 mg/kg ASC22 Q2W for 24 weeks was shown to be safe and well tolerated in virally suppressed CHB patients on NAs and can induce HBsAg decline, especially in patients with HBsAg ≤100 IU/mL.

2.
Biochem Biophys Res Commun ; 497(1): 444-450, 2018 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-29448100

RESUMO

We previously reported that 5-methoxyindole-2-carboxylic acid (MICA) could induce preconditioning effect in the ischemic brain of rat. In the present study, we addressed the question of whether MICA could also trigger a postconditioning effect in ischemic stroke. To this end, MICA (100 mg/kg body weight) was injected intraperitoneally at the onset of 24 h reperfusion following 1 h ischemia in rat brain. Results indicate that stroked animals treated with MICA showed less brain infarction volume than that of vehicle-treated animals. Further experiments revealed that brain mitochondrial complexes I and IV showed elevated enzymatic activities in MICA treated group and the elevation in complex I activity was likely contributed by seemingly enhanced expression of many complex I subunits, which was determined by mass spectral peptide sequencing. When compared with vehicle-treated rats, the preservation of complexes I and IV activities was shown to be accompanied by enhanced mitochondrial membrane potential, increased ATP production, and decreased caspase-3 activity. Additional studies also indicate the involvement of NQO1 upregulation by the Nrf2 signaling pathway in this MICA postconditioning paradigm. Consequently, attenuated oxidative stress in the MICA treated group reflected by decrease in H2O2 production and protein carbonylation and lipid peroxidation was detected. Taken together, the present study demonstrates that MICA can also induce a postconditioning effect in the ischemic brain of rat and the underlying mechanism likely involves preservation of mitochondrial function, upregulation of cellular antioxidative capacity, and attenuation of oxidative stress.


Assuntos
Indóis/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/fisiopatologia , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/fisiopatologia , Animais , Relação Dose-Resposta a Droga , Injeções Intraperitoneais , Masculino , Mitocôndrias/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Reperfusão/métodos , Traumatismo por Reperfusão/etiologia , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
3.
J Gastroenterol Hepatol ; 33(8): 1507-1510, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29346834

RESUMO

BACKGROUND AND AIM: The need for all-oral hepatitis C virus (HCV) treatments with higher response rates, improved tolerability, and lower pill burden compared with interferon-inclusive regimen has led to the development of new direct-acting antiviral agents. Ravidasvir (RDV) is a second-generation, pan-genotypic NS5A inhibitor with high barrier to resistance. The aim of this phase 2 study (EVEREST study) was to assess the efficacy and safety of interferon-free, 12-week RDV plus ritonavir-boosted danoprevir (DNVr) and ribavirin (RBV) regimen for treatment-naïve Asian HCV genotype 1 (GT1) patients without cirrhosis. METHODS: A total of 38 treatment-naïve, non-cirrhotic adult HCV GT1 patients were enrolled in this multicenter, open-label, single-arm phase 2 study (NCT03020095). All patients received a combination of RDV 200 mg once daily (q.d.) plus DNVr 100 mg/100 mg twice daily (b.i.d.) and oral RBV 1000/1200 mg/day (body weight < 75/≥ 75 kg) for 12 weeks. The primary endpoint was the rate of sustained virologic response 12 weeks after the end of treatment (SVR12). RESULTS: Of 38 patients, all (100%) achieved SVR12. During the study, no treatment-related serious adverse events, no patients discontinued treatment due to adverse events, and no deaths were reported. Six of 37 (16%) patients with available sequences had HCV NS5A resistance-associated variants at baseline. All patients (6/6) with baseline NS5A resistance-associated variants achieved SVR12. CONCLUSIONS: Twelve-week RDV and DNVr in combination with RBV for 12 weeks achieves the SVR12 rate of 100% in treatment-naïve non-cirrhotic Asian patients with HCV GT1 infection. This interferon-free regimen is also safe and well tolerated.


Assuntos
Genótipo , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Lactamas/administração & dosagem , Ribavirina/administração & dosagem , Ritonavir/administração & dosagem , Sulfonamidas/administração & dosagem , Administração Oftálmica , Adulto , Idoso , Idoso de 80 Anos ou mais , Antivirais , Povo Asiático , Ciclopropanos , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Isoindóis , Lactamas Macrocíclicas , Cirrose Hepática , Masculino , Pessoa de Meia-Idade , Prolina/análogos & derivados , Fatores de Tempo , Resultado do Tratamento
4.
Int J Mol Sci ; 19(10)2018 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-30274308

RESUMO

Humanin (HN) is a novel 24-amino acid peptide that protects neurons against N-methyl-d-aspartate (NMDA)-induced toxicity. However, the contribution of the different mitogen-activated protein kinases (MAPKs) signals to HN neuroprotection against NMDA neurotoxicity remains unclear. The present study was therefore aimed to investigate neuroprotective mechanisms of HN. We analyzed intracellular Ca2+ levels, reactive oxygen species (ROS) production, and the MAPKs signal transduction cascade using an in vitro NMDA-mediated excitotoxicity of cortical neurons model. Results showed that: (1) HN attenuated NMDA-induced neuronal insults by increasing cell viability, decreasing lactate dehydrogenase (LDH) release, and increasing cell survival; (2) HN reversed NMDA-induced increase in intracellular calcium; (3) pretreatment by HN or 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA-AM), an intracellular calcium chelator, decreased ROS generation after NMDA exposure; (4) administration of HN or N-Acetyl-l-cysteine (NAC), a ROS scavenger, inhibited NMDA-induced JNK and p38 MAPK activation. These results indicated that HN reduced intracellular elevation of Ca2+ levels, which, in turn, inhibited ROS generation and subsequent JNK and p38 MAPK activation that are involved in promoting cell survival in NMDA-induced excitotoxicity. Therefore, the present study suggests that inhibition of ROS-dependent JNK/p38 MAPK signaling pathway serves an effective strategy for HN neuroprotection against certain neurological diseases.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , N-Metilaspartato/toxicidade , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
6.
J Gastroenterol Hepatol ; 31(10): 1757-1765, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26992248

RESUMO

BACKGROUND AND AIM: Chronic hepatitis C is an important public health problem in Asia. We evaluated the safety, efficacy, and pharmacokinetics of fixed-dose ritonavir-boosted danoprevir plus peginterferon alfa-2a/ribavirin in treatment-naive Asian patients with chronic hepatitis C virus (HCV) genotype (G)1 infection. METHODS: Treatment-naive G1 patients in Taiwan, Thailand, and Korea with serum HCV-RNA level ≥ 105 IU/mL received ritonavir-boosted danoprevir 125/100 mg twice daily plus peginterferon alfa-2a/ribavirin for either 12 (noncirrhotic patients: Arm A, n = 34) or 24 weeks (cirrhotic patients: Arm B, n = 27) in this phase II open-label study. Sustained virologic response was defined as HCV-RNA < 25 IU/mL 12 weeks after end of treatment (SVR12). RESULTS: Similar SVR12 rates were achieved in Arms A (88.2%; 95% confidence interval, 73.4-95.3%) and B (88.9%; 71.9-96.2%). Most patients had G1b infection, among whom SVR12 rates in Arms A and B were 96.7% and 91.7%, respectively. The overall SVR12 rate was 94.0% in noncirrhotic Taiwanese patients (100% in the subset of G1b patients). No patients withdrew for safety reasons. Three (11%) cirrhotic patients (Arm B) experienced serious adverse events, none of which was considered to be related to treatment. No Grade 3/4 alanine aminotransferase elevations were reported. The pharmacokinetic properties of danoprevir were broadly overlapping in noncirrhotic and cirrhotic patients both on Days 1 and 14. CONCLUSIONS: Ritonavir-boosted danoprevir plus peginterferon alfa-2a/ribavirin produced sustained virologic response rates > 90% after 12 weeks' treatment in noncirrhotic and 24 weeks' treatment in cirrhotic Asian patients with G1b infection and was well tolerated. These regimens are well suited to countries where G1b predominates.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Adulto , Idoso , Antivirais/efeitos adversos , Antivirais/sangue , Ciclopropanos , Quimioterapia Combinada , Feminino , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/complicações , Humanos , Interferon-alfa/efeitos adversos , Interferon-alfa/sangue , Interferon-alfa/uso terapêutico , Isoindóis , Lactamas/efeitos adversos , Lactamas/sangue , Lactamas/uso terapêutico , Lactamas Macrocíclicas , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , Polietilenoglicóis/uso terapêutico , Prolina/análogos & derivados , RNA Viral/sangue , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/sangue , Proteínas Recombinantes/uso terapêutico , Ribavirina/efeitos adversos , Ribavirina/sangue , Ribavirina/uso terapêutico , Ritonavir/efeitos adversos , Ritonavir/sangue , Ritonavir/uso terapêutico , Sulfonamidas/efeitos adversos , Sulfonamidas/sangue , Sulfonamidas/uso terapêutico , Adulto Jovem
7.
Int J Mol Sci ; 17(3): 351, 2016 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-27005615

RESUMO

It is well established that the brain can be prepared to resist or tolerate ischemic stroke injury, and mitochondrion is a major target for this tolerance. The preparation of ischemic stroke tolerance can be achieved by three major approaches: ischemic conditioning, hypoxic conditioning and chemical conditioning. In each conditioning approach, there are often two strategies that can be used to achieve the conditioning effects, namely preconditioning (Pre-C) and postconditioning (Post-C). In this review, we focus on chemical conditioning of mitochondrial proteins as targets for neuroprotection against ischemic stroke injury. Mitochondrial targets covered include complexes I, II, IV, the ATP-sensitive potassium channel (mitoKATP), adenine dinucleotide translocase (ANT) and the mitochondrial permeability transition pore (mPTP). While numerous mitochondrial proteins have not been evaluated in the context of chemical conditioning and ischemic stroke tolerance, the paradigms and approaches reviewed in this article should provide general guidelines on testing those mitochondrial components that have not been investigated. A deep understanding of mitochondria as the target of chemical conditioning for ischemic stroke tolerance should provide valuable insights into strategies for fighting ischemic stroke, a leading cause of death in the world.


Assuntos
Isquemia Encefálica/complicações , Pós-Condicionamento Isquêmico , Precondicionamento Isquêmico , Mitocôndrias/metabolismo , Proteínas Mitocondriais/efeitos dos fármacos , Acidente Vascular Cerebral/etiologia , Animais , Encéfalo/irrigação sanguínea , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores , Acidente Vascular Cerebral/tratamento farmacológico
8.
Int J Med Sci ; 12(5): 432-40, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26078703

RESUMO

Intermittent hypoxia preconditioning (IHP) has been shown to protect neurons against ischemic stroke injury. Studying how proteins respond to IHP may identify targets that can help fight stroke. The objective of the present study was to investigate whether mitochondrial dihydrolipoamide dehydrogenase (DLDH) would respond to IHP and if so, whether such a response could be linked to neuroprotection in ischemic stroke injury. To do this, we subjected male rats to IHP for 20 days and measured the content and activity of DLDH as well as the three α-keto acid dehydrogenase complexes that contain DLDH. We also measured mitochondrial electron transport chain enzyme activities. Results show that DLDH content was indeed upregulated by IHP and this upregulation did not alter the activities of the three α-keto acid dehydrogenase complexes. Results also show that the activities of the five mitochondrial complexes (I-V) were not altered either by IHP. To investigate whether IHP-induced DLDH upregulation is linked to neuroprotection against ischemic stroke injury, we subjected both DLDH deficient mouse and DLDH transgenic mouse to stroke surgery followed by measurement of brain infarction volume. Results indicate that while mouse deficient in DLDH had exacerbated brain injury after stroke, mouse overexpressing human DLDH also showed increased brain injury after stroke. Therefore, the physiological significance of IHP-induced DLDH upregulation remains to be further investigated.


Assuntos
Isquemia Encefálica/metabolismo , Di-Hidrolipoamida Desidrogenase/metabolismo , Mitocôndrias/metabolismo , Animais , Isquemia Encefálica/patologia , Hipóxia Celular , Di-Hidrolipoamida Desidrogenase/genética , Modelos Animais de Doenças , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Precondicionamento Isquêmico , Camundongos Transgênicos , Ratos , Regulação para Cima
9.
Theranostics ; 14(6): 2427-2441, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646649

RESUMO

Background: MER proto-oncogene tyrosine kinase (MerTK) is a key receptor for efferocytosis, a process for the clearance of apoptotic cells. MerTK is mainly expressed in macrophages and immature dendritic cells. There are very limited reports focused on MerTK biology in aortic endothelial cells (ECs). It remains unclear for the role of blood flow patterns in regulating MerTK-mediated efferocytosis in aortic ECs. This study was designed to investigate whether endothelial MerTK and EC efferocytosis respond to blood flow patterns during atherosclerosis. Methods: Big data analytics, RNA-seq and proteomics combined with our in vitro and in vivo studies were applied to reveal the potential molecular mechanisms. Partial carotid artery ligation combined with AAV-PCSK9 and high fat diet were used to set up acute atherosclerosis in 4 weeks. Results: Our data showed that MerTK is sensitive to blood flow patterns and is inhibited by disturbed flow and oscillatory shear stress in primary human aortic ECs (HAECs). The RNA-seq data in HAECs incubated with apoptotic cells showed that d-flow promotes pro-inflammatory pathway and senescence pathway. Our in vivo data of proteomics and immunostaining showed that, compared with WT group, MerTK-/- aggravates atherosclerosis in d-flow areas through upregulation of endothelial dysfunction markers (e.g. IL-1ß, NF-κB, TLR4, MAPK signaling, vWF, VCAM-1 and p22phox) and mitochondrial dysfunction. Interestingly, MerTK-/-induces obvious abnormal endothelial thickening accompanied with decreased endothelial efferocytosis, promoting the development of atherosclerosis. Conclusions: Our data suggests that blood flow patterns play an important role in regulating MerTK-mediated efferocytosis in aortic ECs, revealing a new promising therapeutic strategy with EC efferocytosis restoration to against atherosclerosis.


Assuntos
Aorta , Aterosclerose , Células Endoteliais , Fagocitose , c-Mer Tirosina Quinase , c-Mer Tirosina Quinase/metabolismo , c-Mer Tirosina Quinase/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Aterosclerose/fisiopatologia , Humanos , Células Endoteliais/metabolismo , Animais , Aorta/metabolismo , Aorta/patologia , Camundongos , Apoptose , Proto-Oncogene Mas , Masculino , Camundongos Endogâmicos C57BL , Dieta Hiperlipídica , Células Cultivadas , Eferocitose
10.
Redox Biol ; 70: 103061, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38341954

RESUMO

RATIONALE: MER proto-oncogene tyrosine kinase (MerTK) is a key receptor for the clearance of apoptotic cells (efferocytosis) and plays important roles in redox-related human diseases. We will explore MerTK biology in human cells, tissues, and diseases based on big data analytics. METHODS: The human RNA-seq and scRNA-seq data about 42,700 samples were from NCBI Gene Expression Omnibus and analyzed by QIAGEN Ingenuity Pathway Analysis (IPA) with about 170,000 crossover analysis. MerTK expression was quantified as Log2 (FPKM + 0.1). RESULTS: We found that, in human cells, MerTK is highly expressed in macrophages, monocytes, progenitor cells, alpha-beta T cells, plasma B cells, myeloid cells, and endothelial cells (ECs). In human tissues, MerTK has higher expression in plaque, blood vessels, heart, liver, sensory system, artificial tissue, bone, adrenal gland, central nervous system (CNS), and connective tissue. Compared to normal conditions, MerTK expression in related tissues is altered in many human diseases, including cardiovascular diseases, cancer, and brain disorders. Interestingly, MerTK expression also shows sex differences in many tissues, indicating that MerTK may have different impact on male and female. Finally, based on our proteomics from primary human aortic ECs, we validated the functions of MerTK in several human diseases, such as cancer, aging, kidney failure and heart failure. CONCLUSIONS: Our big data analytics suggest that MerTK may be a promising therapeutic target, but how it should be modulated depends on the disease types and sex differences. For example, MerTK inhibition emerges as a new strategy for cancer therapy due to it counteracts effect on anti-tumor immunity, while MerTK restoration represents a promising treatment for atherosclerosis and myocardial infarction as MerTK is cleaved in these disease conditions.


Assuntos
Receptores Proteína Tirosina Quinases , c-Mer Tirosina Quinase , Feminino , Humanos , Masculino , Apoptose/genética , c-Mer Tirosina Quinase/genética , Ciência de Dados , Células Endoteliais/metabolismo , Genômica , Neoplasias/metabolismo , Fagocitose , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Encefalopatias/metabolismo
11.
Expert Opin Investig Drugs ; : 1-10, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38988285

RESUMO

BACKGROUND: Considering the rise of new SARS-CoV-2 variants that have reduced the efficacy of COVID-19 vaccines, the development of new antiviral medications for the disease has become increasingly necessary. In this study, ASC10, a novel antiviral prodrug, was studied in a phase 1 trial in healthy Chinese participants. RESEARCH DESIGN AND METHODS: Part 1 involved 60 participants, receiving 50-800 mg ASC10 or placebo twice daily for 5.5 days. Part 2, with 12 participants, explored ASC10 dosing in the fed/fasting states. RESULTS: ASC10-A, the main pharmacologically active metabolite, rapidly appeared in plasma (Tmax: 1.00-2.00 h) and decreased (t1/2: 1.10-3.04 h) without accumulation. The Cmax and area under the plasma concentration - time curve (AUC) of ASC10-A increased dose-dependently (50-800 mg BID) over 5.5 days, with no accumulation. The Tmax was slightly delayed in the fed state; however, the Cmax and AUC were similar between the fed and fasting states. Adverse events (AEs) were comparable (ASC10/placebo, 66.7%) and mostly mild (95%). CONCLUSION: ASC10 was demonstrated to be safe and well tolerated and exhibited dose-proportional exposure and minimal food effects. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov identifier is NCT05523141.

12.
Drugs R D ; 23(4): 453-464, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37919483

RESUMO

BACKGROUND: ASC42 is a non-steroidal farnesoid X receptor agonist currently in clinical development for chronic liver diseases, such as nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH) and primary biliary cirrhosis (PBC). OBJECTIVE: The objective of this study was to assess the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of ASC42 in healthy subjects. METHODS: We conducted the first-in-human study of ASC42 following single and multiple ascending doses (SAD/MAD) and food effect in healthy subjects. The SAD study included five cohorts receiving 5-200 mg ASC42 or placebo and one cohort that was given 15 mg ASC42 with a high-fat meal. The MAD study included three cohorts receiving 5-50 mg ASC42 or placebo once-daily (QD) for 14 days. RESULTS: A total of 65 healthy subjects were enrolled and one subject in the MAD study (cohort 8, ASC42 50 mg) withdrew from the study due to an unrelated serious adverse event (SAE) of atrial fibrillation. Pruritus was observed at the highest doses (200 mg cohort in SAD and 50 mg cohort in MAD). Most AEs were mild or moderate. No life-threatening or fatal AEs occurred. ASC42 showed a proportional increase in exposure and elimination half-life following both single and multiple dosing. There was a 21% and 37% decrease in area under the curve (AUC) and maximum plasma concentration (Cmax) when ASC42 was coadministered with food. The steady state was reached on day 4 with a mild accumulation (1.02-1.74-fold). ASC42 showed dose-dependent increases in fibroblast growth factor 19 and decreases in 7α-hydroxy-4-cholesten-3-one. Cholesterol remained within normal limits during study. CONCLUSION: ASC42 was well tolerated with a pharmacokinetic profile suitable for QD dosing, and demonstrated dose-dependent targets engagement without altering plasma cholesterol in healthy subjects. TRIAL REGISTRATION NUMBER: NCT04679129.


Assuntos
Colesterol , Humanos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Área Sob a Curva , Voluntários Saudáveis
13.
Theranostics ; 13(9): 2914-2929, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37284459

RESUMO

Aims: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a serine protease that binds to low-density lipoprotein receptors. Efferocytosis is the process by which phagocytes remove apoptotic cells. Both PCSK9 and efferocytosis play important roles in regulating redox biology and inflammation, the key factors contributing to vascular aging. This study was designed to investigate the impact of PCSK9 on efferocytosis in endothelial cells (ECs) and its implications in vascular aging. Methods and Results: Studies were performed in primary human aortic ECs (HAECs) and primary mouse aortic ECs (MAECs) isolated from male wild-type (WT) and PCSK9-/- mice, and in young and aged mice treated with saline or the PCSK9 inhibitor Pep2-8. Our findings include that recombinant PCSK9 protein induces defective efferocytosis and aging marker senescence-associated-ß-galactosidase (SA-ß-gal) expression in ECs, while PCSK9-/- restores efferocytosis and inhibits SA-ß-gal activity. Further studies in aged mice showed that endothelial deficiency of MerTK, a critical receptor for efferocytosis that allows phagocytes to detect the presence of apoptotic cells, may be an indicator of vascular dysfunction in the aortic arch. Pep2-8 treatment markedly restored efferocytosis in endothelium from the aged mice. A proteomics study in the aortic arch from aged mice revealed that Pep2-8 administration significantly downregulates expression of NOX4, MAPK subunits, NF-κB, and secretion of pro-inflammatory cytokines, all known to promote vascular aging. Immunofluorescent staining showed that Pep2-8 administration upregulates expression of eNOS and downregulates expression of pro-IL-1ß, NF-κB and p22phox compared to saline treated group. Conclusions: These findings provide initial evidence for the ability of aortic ECs to accomplish efferocytosis and argue for a role of PCSK9 in attenuating EC efferocytosis, thereby leading to vascular dysfunction and acceleration in vascular aging.


Assuntos
Células Endoteliais , Pró-Proteína Convertase 9 , Masculino , Camundongos , Humanos , Animais , Pró-Proteína Convertase 9/genética , Células Endoteliais/metabolismo , NF-kappa B/metabolismo , Envelhecimento
14.
Mol Ther ; 18(4): 828-34, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20068551

RESUMO

We have designed a PEGylated LPD (liposome-polycation-DNA) nanoparticle for systemic, specific, and efficient delivery of small interfering RNA (siRNA) into solid tumors in mice by modification with NGR (aspargine-glycine-arginine) peptide, targeting aminopeptidase N (CD13) expressed in the tumor cells or tumor vascular endothelium. LPD-PEG-NGR efficiently delivered siRNA to the cytoplasm and downregulated the target gene in the HT-1080 cells but not CD13(-) HT-29 cells, whereas nanoparticles containing a control peptide, LPD-PEG-ARA, showed only little siRNA uptake and gene silencing activity. LPD-PEG-NGR efficiently delivered siRNA into the cytoplasm of HT-1080 xenograft tumor 4 hours after intravenous injection. Three daily injections (1.2 mg/kg) of c-myc siRNA formulated in the LPD-PEG-NGR effectively suppressed c-myc expression and triggered cellular apoptosis in the tumor, resulting in a partial tumor growth inhibition. When doxorubicin (DOX) and siRNA were co-formulated in LPD-PEG-NGR, an enhanced therapeutic effect was observed.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Genes myc , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Oligopeptídeos/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , Animais , Apoptose , Antígenos CD13/farmacologia , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Endotélio Vascular , Células HT29 , Humanos , Lipossomos , Camundongos , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Clocks Sleep ; 2(3): 325-333, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33089207

RESUMO

Sleep deprivation is a potent stress factor that disrupts regulatory pathways in the brain resulting in cognitive dysfunction and increased risk of neurodegenerative disease with increasing age. Prevention of the adverse effects of sleep deprivation could be beneficial in older individuals by restoring healthy brain function. We report here on the ability of SS31, a mitochondrial specific peptide, to attenuate the negative neurological effects of short-term sleep deprivation in aging mice. C57BL/6 female mice, 20 months old, were subcutaneously injected with SS31 (3 mg/kg) or saline daily for four days. Sleep deprivation was 4 h daily for the last two days of SS31 treatment. Mice were immediately tested for learning ability followed by collection of brain and other tissues. In sleep deprived mice treated with SS31, learning impairment was prevented, brain mitochondrial ATP levels and synaptic plasticity regulatory proteins were restored, and reactive oxygen species (ROS) and inflammatory cytokines levels were decreased in the hippocampus. This observation suggests possible therapeutic benefits of SS31 for alleviating adverse neurological effects of short-term sleep loss.

16.
Diabetes Metab Syndr Obes ; 13: 2147-2155, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606873

RESUMO

INTRODUCTION: The purpose of the present study was to reveal the potential positive effect of the Ta-ermi extracts on oxidative stress and streptozotocin (STZ)-diabetic mice and rats treated with Ta-ermi water- and alcohol-extracts. METHODS: The study was carried out using three experimental model: 1) in vitro experiments whereby Ta-ermi extracts were incubated with free radical generators such as 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) to evaluate Ta-ermi's antioxidant effects; 2) testing the hypoglycemic effects of Ta-ermi extracts in streptozotocin (STZ)-induced diabetic mice; and 3) testing the beneficial effects of Ta-ermi extracts on mitochondrial complex I function using STZ-diabetic rats. RESULTS: In vitro antioxidant experiments showed that both of the extracts could scavenge free radicals and exhibited inhibitory effects on glucosidase and aldose reductase with differential effects between water extract and alcohol extract. In the STZ mouse diabetic model, both the water- and alcohol-extracts attenuated body weight decrease, decreased blood glucose levels in a concentration-dependent manner, improved insulin sensitivity, and increased oral glucose tolerance ability. In the STZ-diabetic rat model, both the water- and alcohol-extracts were found to be able to lower blood glucose levels in the diabetic animals with no effects on body weight changes. Moreover, in the STZ-diabetic rats, both the water- and alcohol-extracts of Ta-ermi could inhibit the increase of mitochondrial NADH/ubiquinone oxidoreductase (complex I) activity in the pancreas and enhanced complex I activity in the liver but showed no effect on lung or kidney mitochondrial complex I. DISCUSSION: The present study points to the potential medicinal value of Ta-ermi's water and alcohol extracts in lowering blood glucose and decreasing diabetic oxidative stress. One limitation of our study is that the compound or compounds that actually have this beneficial effect in the extracts remain unknown at this time. Therefore, the future studies should be focused on the identification of the components in the extracts that exhibit anti-oxidative and hypoglycemic effects. CONCLUSION: Taken together, our studies using different experimental paradigms indicate that Ta-ermi extracts possess antioxidant and anti-diabetic properties and may be employed as functional food ingredients for the remission of diabetes.

17.
Rev Soc Bras Med Trop ; 53: e20200372, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32696811

RESUMO

Coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been declared a pandemic. We herein report four COVID-19 cases with long-term positive viral ribonucleic acid (RNA) for about 61 days. Despite treatment with recombinant human interferon, convalescent plasma from COVID-19 patients, arbidol, etc., nucleic acid results were still positive for SARS-CoV-2. After treatment with ritonavir-boosted danoprevir (DNVr, 100/100 mg, once daily), all four patients showed two to three consecutive negative SARS-CoV-2 RNA and were thus discharged from hospital. Therefore, DNVr may be a potentially effective antiviral for COVID-19 patients with long-term positive SARS-CoV-2 RNA.


Assuntos
Antivirais , Infecções por Coronavirus , Coronavirus , Pandemias , Pneumonia Viral , RNA Viral , Adulto , Idoso , Antivirais/uso terapêutico , Betacoronavirus , COVID-19 , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , RNA Viral/sangue , SARS-CoV-2 , Tratamento Farmacológico da COVID-19
18.
Medicine (Baltimore) ; 99(48): e23357, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33235105

RESUMO

INTRODUCTION: As coronavirus disease 2019 (COVID-19) outbreak globally, repurposing approved drugs is emerging as important therapeutic options. Danoprevir boosted by ritonavir (Ganovo) is a potent hepatitis C virus (HCV) protease (NS3/4A) inhibitor, which was approved and marketed in China since 2018 to treat chronic hepatitis C patients. METHODS: This is an open-label, single arm study evaluating the effects of danoprevir boosted by ritonavir on treatment naïve and experienced COVID-19 patients for the first time. Patients received danoprevir boosted by ritonavir (100 mg/100 mg, twice per day). The primary endpoint was the rate of composite adverse outcomes and efficacy was also evaluated. RESULTS: The data showed that danoprevir boosted by ritonavir is safe and well tolerated in all patients. No patient had composite adverse outcomes during this study. After initiation of danoprevir/ritonavir treatment, the first negative reverse real-time PCR (RT-PCR) test occurred at a median of 2 days, ranging from 1 to 8 days, and the obvious absorption in CT scans occurred at a median 3 days, ranging from 2 to 4 days. After 4 to 12-day treatment of danoprevir boosted by ritonavir, all enrolled 11 patients were discharged from the hospital. CONCLUSION: Our findings suggest that repurposing danoprevir for COVID-19 is a promising therapeutic option.


Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Ciclopropanos/uso terapêutico , Isoindóis/uso terapêutico , Lactamas Macrocíclicas/uso terapêutico , Prolina/análogos & derivados , Ritonavir/uso terapêutico , Sulfonamidas/uso terapêutico , Adolescente , Adulto , Idoso , Antivirais/administração & dosagem , Antivirais/efeitos adversos , COVID-19/diagnóstico por imagem , Ciclopropanos/administração & dosagem , Ciclopropanos/efeitos adversos , Quimioterapia Combinada , Feminino , Humanos , Isoindóis/administração & dosagem , Isoindóis/efeitos adversos , Lactamas Macrocíclicas/administração & dosagem , Lactamas Macrocíclicas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Pandemias , Prolina/administração & dosagem , Prolina/efeitos adversos , Prolina/uso terapêutico , Reação em Cadeia da Polimerase em Tempo Real , Ritonavir/administração & dosagem , Ritonavir/efeitos adversos , SARS-CoV-2 , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos , Tomografia Computadorizada por Raios X , Adulto Jovem
19.
Toxicol Lett ; 322: 66-76, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31945382

RESUMO

Silent Information Regulator 1 (SIRT1), an NAD+-dependent deacetylase, contributes to the neuroprotective effect. However, intracellular signaling pathways that affect SIRT1 function remain unknown. It is well known that N-methyl-D-aspartate (NMDA) receptor activation induces calcium influx which then activates PKC, and SIRT1 is a mRNA target for HuR protein. We hypothesize that Ca2+-PKC-HuR-SIRT1 pathway modulates SIRT1 function. The present study is to investigate the potential pathway of SIRT1 in the SH-SY5Y cell line as an in vitro model of NMDA-induced neurotoxicity. The results showed that: (1) SIRT1 levels were downregulated in NMDA model; (2) NMDA induced an increase in serine phosphorylation of HuR, while inhibition of serine phosphorylation of HuR increased SIRT1 levels, promoting cell survival; (3) PKC inhibitor (Gö 6976) reversed NMDA insults and also suppressed serine phosphorylation of HuR; (4) 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA-AM), an intracellular calcium chelator, fully reversed NMDA insults and also inhibited PKC activity evoked by NMDA. These results indicate that intracellular elevated Ca2+ activates PKC, which phosphorylates HuR and then promotes SIRT1 mRNA decay and subsequent neuronal death in NMDA model. Therefore, the study suggests that inhibition of Ca2+-PKC-HuR-SIRT1 pathway could be an effective strategy for preventing certain neurological diseases related to NMDA excitotoxicity.


Assuntos
Agonistas de Aminoácidos Excitatórios/toxicidade , N-Metilaspartato/toxicidade , Neurônios/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Sirtuína 1/metabolismo , Cálcio/metabolismo , Sinalização do Cálcio , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo , Proteína Semelhante a ELAV 1/metabolismo , Humanos , Neurônios/enzimologia , Neurônios/patologia , Síndromes Neurotóxicas/enzimologia , Síndromes Neurotóxicas/patologia , Fosforilação , Proteína Quinase C/metabolismo , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Serina , Sirtuína 1/genética
20.
Neural Regen Res ; 15(3): 548-556, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31571667

RESUMO

Orientin is a flavonoid monomer. In recent years, its importance as a source of pharmacological active substance is growing rapidly due to its properties such as anti-myocardial ischemia, anti-apoptosis, anti-radiation, anti-tumor, and anti-aging. However, the neuroprotective effects of Orientin on stroke injury have not been comprehensively evaluated. The aim of the present study was thus to investigate the neuroprotective capacity and the potential mechanisms of Cyperus esculentus L. orientin (CLO) from Cyperus esculentus L. leaves against ischemia/reperfusion (I/R) injury using standard orientin as control. For in vitro studies, we treated HT22 cells with CoCl2 as an in vitro ischemic injury model. HT22 cells in the control group were treated with CoCl2. For in vivo studies, we used rat models of middle cerebral artery occlusion, and animals that received sham surgery were used as controls. We found that CLO protected CoCl2-induced HT22 cells against ischemia/reperfusion injury by lowering lipid peroxidation and reactive oxygen species formation as well as decreasing protein oxidation. However, CLO did not reduce the release of lactate dehydrogenase nor increase the activity of superoxide dismutase. Results showed that CLO could decrease neurological deficit score, attenuate brain water content, and reduce cerebral infarct volume, leading to neuroprotection during cerebral ischemia-reperfusion injury. Our studies indicate that CLO flavonoids can be taken as a natural antioxidant and bacteriostastic substance in food and pharmaceutical industry. The molecular mechanisms of CLO could be at least partially attributed to the antioxidant properties and subsequently inhibiting activation of casepase-3. All experimental procedures and protocols were approved on May 16, 2016 by the Experimental Animal Ethics Committee of Xinjiang Medical University of China (approval No. IACUC20160516-57).

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