RESUMO
Apoptosis plays a crucial role in neuronal injury, with substantial evidence implicating Fas-mediated cell death as a key factor in ischemic strokes. To address this, inhibition of Fas-signaling has emerged as a promising strategy in preventing neuronal cell death and alleviating brain ischemia. However, the challenge of overcoming the blood-brain barrier (BBB) hampers the effective delivery of therapeutic drugs to the central nervous system (CNS). In this study, we employed a 30 amino acid-long leptin peptide to facilitate BBB penetration. By conjugating the leptin peptide with a Fas-blocking peptide (FBP) using polyethylene glycol (PEG), we achieved specific accumulation in the Fas-expressing infarction region of the brain following systemic administration. Notably, administration in leptin receptor-deficient db/db mice demonstrated that leptin facilitated the delivery of FBP peptide. We found that the systemic administration of leptin-PEG-FBP effectively inhibited Fas-mediated apoptosis in the ischemic region, resulting in a significant reduction of neuronal cell death, decreased infarct volumes, and accelerated recovery. Importantly, neither leptin nor PEG-FBP influenced apoptotic signaling in brain ischemia. Here, we demonstrate that the systemic delivery of leptin-PEG-FBP presents a promising and viable strategy for treating cerebral ischemic stroke. Our approach not only highlights the therapeutic potential but also emphasizes the importance of overcoming BBB challenges to advance treatments for neurological disorders.
Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Animais , Camundongos , Leptina/farmacologia , Apoptose , Isquemia Encefálica/tratamento farmacológico , Morte Celular , Peptídeos/farmacologiaRESUMO
Evaluation of the therapeutic potential of RNAi for HIV infection has been hampered by the challenges of siRNA delivery and lack of suitable animal models. Using a delivery method for T cells, we show that siRNA treatment can dramatically suppress HIV infection. A CD7-specific single-chain antibody was conjugated to oligo-9-arginine peptide (scFvCD7-9R) for T cell-specific siRNA delivery in NOD/SCIDIL2rgamma-/- mice reconstituted with human lymphocytes (Hu-PBL) or CD34+ hematopoietic stem cells (Hu-HSC). In HIV-infected Hu-PBL mice, treatment with anti-CCR5 (viral coreceptor) and antiviral siRNAs complexed to scFvCD7-9R controlled viral replication and prevented the disease-associated CD4 T cell loss. This treatment also suppressed endogenous virus and restored CD4 T cell counts in mice reconstituted with HIV+ peripheral blood mononuclear cells. Moreover, scFvCD7-9R could deliver antiviral siRNAs to naive T cells in Hu-HSC mice and effectively suppress viremia in infected mice. Thus, siRNA therapy for HIV infection appears to be feasible in a preclinical animal model.
Assuntos
Infecções por HIV/genética , Infecções por HIV/terapia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Linfócitos T/metabolismo , Animais , Antígenos CD7/metabolismo , Modelos Animais de Doenças , Expressão Gênica , HIV-1/genética , HIV-1/metabolismo , Humanos , Fragmentos de Imunoglobulinas/metabolismo , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/virologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , RNA Viral/metabolismoRESUMO
BACKGROUND: With the recent rapid increase in the prevalence of obesity, the number of obese patients requiring liver resection, including laparoscopy, has increased. Accordingly, evaluating the outcome of laparoscopic liver resection in obese patients is increasingly important. This study aimed to compare the safety and feasibility of laparoscopic major liver resection (LMR) and open major liver resection (OMR) in patients with a high body mass index (BMI > 25.0 kg/m2). METHODS: We reviewed 521 patients with high BMI (> 25.0 kg/m2) who underwent major liver resection for various indications between January 2009 and November 2018 at Asan Medical Center. We performed 1:1 propensity score matching of the LMR and OMR groups, with 120 patients subsequently included in each group. RESULTS: LMR was associated with lower blood loss and shorter postoperative hospital stays (p < 0.001). Although there was no significant difference in overall complications (p = 0.080), non-liver-specific complications were observed less frequently after LMR (p = 0.025). American Society of Anesthesiologists class > II, BMI > 30 kg/m2, and malignancy were independent predictors of morbidity. In a subgroup analysis of patients with hepatocellular carcinoma, there was no significant difference between the two groups in overall survival (hazard ratio 0.225; 95% confidence interval 0.049-1.047; p = 0.057) and recurrence-free survival (hazard ratio 0.761; 95% confidence interval 0.394-1.417; p = 0.417). CONCLUSIONS: Obesity should not be considered a contraindication for major liver resection using a laparoscopic approach; however, when applying this approach for resecting malignancies in patients with a BMI > 30 kg/m2 and comorbid diseases, special attention should be paid to the possibility of complications.
Assuntos
Laparoscopia , Neoplasias Hepáticas , Índice de Massa Corporal , Hepatectomia , Humanos , Tempo de Internação , Obesidade/complicações , Obesidade/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Pontuação de Propensão , Estudos Retrospectivos , Resultado do TratamentoRESUMO
We demonstrate the measurement of the transverse spin relaxation rate of Xe without the influence of the Rb polarization-induced magnetic field gradient. The optical pumping beam and probe beam turn on and off repeatedly during the measurement to reduce the relaxation originating from the Rb polarization-induced magnetic field gradient. During the absence of the optical pumping beam, the nuclear spin of the noble gas atom does not experience the alkali-polarization-induced magnetic field gradient so that the transverse spin relaxation rate (1/T2) decreases. When the duty cycle reaches zero, the measured transverse relaxation time T2 approaches the longitudinal spin relaxation time T1. Our method helps in roughly estimating the longitudinal spin relaxation time with a single measurement of the free induction decay.
RESUMO
Ischemic heart disease, especially myocardial infarction (MI), is the leading cause of death worldwide. Apoptotic mechanisms are thought to play a significant role in cardiomyocyte death after MI. Increased production of heat shock proteins (Hsps) in cardiomyocytes is a normal response to promote tolerance and to reduce cell damage. Hsp27 is considered to be a therapeutic option for the treatment of ischemic heart disease due to its protective effects on hypoxia-induced apoptosis. Despite its antiapoptotic effects, the lack of strategies to deliver Hsp27 to the heart tissue in vivo limits its clinical applicability. In this study, we utilized an antibody against the angiotensin II type 1 (AT1) receptor, which is expressed immediately after ischemia/reperfusion in the heart of MI rats. To achieve cardiomyocyte-targeted Hsp27 delivery after ischemia/reperfusion, we employed the immunoglobulin-binding dimer ZZ, a modified domain of protein A, in conjunction with the AT1 receptor antibody. Using the AT1 receptor antibody, we achieved systemic delivery of ZZ-TAT-GFP fusion protein into the heart of MI rats. This approach enabled selective delivery of Hsp27 to cardiomyocytes, rescued cells from apoptosis, reduced the area of fibrosis, and improved cardiac function in the rat MI model, thus suggesting its applicability as a cardiomyocyte-targeted protein delivery system to inhibit apoptosis induced by ischemic injury.
Assuntos
Proteínas de Choque Térmico HSP27/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Miócitos Cardíacos/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Animais , Anticorpos Monoclonais , Linhagem Celular Tumoral , Feminino , Proteínas de Choque Térmico HSP27/genética , Humanos , Infarto do Miocárdio/genética , Ratos , Receptor Tipo 1 de Angiotensina/genéticaRESUMO
Glioblastoma multiforme (GBM) is an aggressive tumor with no curative treatment. The tumor recurrence after resection often requires chemotherapy or radiation to delay the infiltration of tumor remnants. Intracerebral chemotherapies are preferentially being used to prevent tumor regrowth, but treatments remain unsuccessful because of the poor drug distribution in the brain. In this study, we investigated the therapeutic efficacy of cancer-targeting arginyl-glycyl-aspartic tripeptide (RGD) conjugated paclitaxel (PTX)-loaded nanoparticles (NPs) against GBM by nose-to-brain delivery. Our results demonstrated that RGD-modified PTX-loaded NPs showed cancer-specific delivery and enhanced anticancer effects in vivo. The intranasal (IN) inoculation of RGD-PTX-loaded NPs effectively controls the tumor burden (75 ± 12% reduction) by inducing apoptosis and/or inhibiting cancer cell proliferation without affecting the G0 stage of normal brain cells. Our data provide therapeutic evidence supporting the use of intranasally delivered cancer-targeted PTX-loaded NPs for GBM therapy.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Encéfalo/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Nanopartículas/química , Paclitaxel/farmacologia , Peptídeos/química , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , Nariz , Paclitaxel/química , Ratos , Ratos Sprague-Dawley , Carga Tumoral/efeitos dos fármacosRESUMO
OBJECTIVE: We aimed to describe our experience with pure laparoscopic right hepatectomy (LRH) and to compare its outcomes with those of open right hepatectomy (ORH) in hepatocellular carcinoma (HCC) patients with liver cirrhosis. BACKGROUND: Laparoscopic liver resection has been reported as a safe and effective approach for the management of liver cancer; however, its outcomes have not been evaluated in a large cohort of HCC patients with liver cirrhosis. METHODS: We retrospectively reviewed the medical records of 152 patients who underwent pure LRH (n = 37) or ORH (n = 115) between June 2008 and July 2015 at the Asan Medical Center in Seoul, Korea. We performed 1:1 propensity score matching between the LRH and ORH groups. Subsequently, 33 patients were included in each group. RESULTS: There was no statistically significant difference between the LRH and ORH groups regarding the rate of complications (P = 0.053). However, the mean comprehensive complication index, which accounts for the severity of complications, was significantly lower in the LRH group (0.63 vs 4.42; P = 0.025). There were no significant differences between the LRH and ORH groups regarding 2-year disease-free survival rate or 2-year overall survival rate (P = 0.645 and P = 0.090, respectively). CONCLUSIONS: Even in patients with cirrhosis, pure LRH is not less safe than the traditional open approach. The oncological outcomes of HCC were also comparable between the two groups. In selected patients, pure LRH for HCC appears to represent a viable alternative to ORH.
Assuntos
Carcinoma Hepatocelular/cirurgia , Laparoscopia/métodos , Laparotomia/métodos , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/mortalidade , Distribuição de Qui-Quadrado , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Seguimentos , Hepatectomia/métodos , Humanos , Estimativa de Kaplan-Meier , Cirrose Hepática/complicações , Cirrose Hepática/mortalidade , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios/métodos , Pontuação de Propensão , República da Coreia , Estudos Retrospectivos , Medição de Risco , Estatísticas não Paramétricas , Taxa de Sobrevida , Resultado do TratamentoRESUMO
RNA-guided endonucleases (RGENs) derived from the CRISPR/Cas system represent an efficient tool for genome editing. RGENs consist of two components: Cas9 protein and guide RNA. Plasmid-mediated delivery of these components into cells can result in uncontrolled integration of the plasmid sequence into the host genome, and unwanted immune responses and potential safety problems that can be caused by the bacterial sequences. Furthermore, this delivery method requires transfection tools. Here we show that simple treatment with cell-penetrating peptide (CPP)-conjugated recombinant Cas9 protein and CPP-complexed guide RNAs leads to endogenous gene disruptions in human cell lines. The Cas9 protein was conjugated to CPP via a thioether bond, whereas the guide RNA was complexed with CPP, forming condensed, positively charged nanoparticles. Simultaneous and sequential treatment of human cells, including embryonic stem cells, dermal fibroblasts, HEK293T cells, HeLa cells, and embryonic carcinoma cells, with the modified Cas9 and guide RNA, leads to efficient gene disruptions with reduced off-target mutations relative to plasmid transfections, resulting in the generation of clones containing RGEN-induced mutations. Our CPP-mediated RGEN delivery process provides a plasmid-free and additional transfection reagent-free method to use this tool with reduced off-target effects. We envision that our method will facilitate RGEN-directed genome editing.
Assuntos
Sistemas CRISPR-Cas , Peptídeos Penetradores de Células/química , RNA Guia de Cinetoplastídeos/genética , Transfecção/métodos , Linhagem Celular Tumoral , Genoma Humano , Células HEK293 , Humanos , Mutagênese Sítio-Dirigida/métodos , Nanopartículas/química , Edição de RNA , RNA Guia de Cinetoplastídeos/químicaRESUMO
BACKGROUND: Laparoscopic hepatectomy is a common procedure that has been reported frequently [1-3]. However, laparoscopic resection of tumors located in hepatic segments 5 and/or 8 remains a technically difficult procedure as it requires two transection planes [4]. Furthermore, there are a greater number of hepatic vein and glissonian pedicle branches that require a division as compared to other hepatectomy operations. In this report, we present a pure laparoscopic right anterior sectionectomy (RAS) for hepatocellular carcinoma (HCC). METHODS: Preoperative imaging showed HCC (3 cm × 4 cm) in segment 5 [5]. After selective anterior segment inflow occlusion, transection lines were demarcated. Complete Pringle maneuver was performed for 15 min intervals five times during hepatic parenchymal transection. The Cavitron Ultrasonic Surgical Aspirator was used for the transection of the hepatic tissue. Small hepatic vein branches along the middle and right hepatic veins and small glissonian pedicles were clipped, sealed and divided with EnSEAL (TM) (Ethicon). iDrive (TM) Ultra Powered Stapling device (Medtronic) was used for the division of tertiary glissonian pedicles. Hanging maneuver was performed for transection of remaining liver parenchyma after complete division of hepatic venous branches. The specimen was removed through the lower abdominal transverse incision using the endocatch bag. Jackson-Pratt drain was left in the operative field. All work was performed with IRB approval. RESULTS: Pure laparoscopic RAS for HCC was performed successfully without intraoperative complications or transfusions. The operation time was 300 min, and the estimated blood loss was <200 ml. On postoperative day 5, computed tomography scan showed well-perfused hepatic parenchyma. Pathology specimen confirmed 3.2 cm × 3 cm × 2.2 cm HCC without involvement of surgical resection margins. The patient was discharged on postoperative day 7 without complications. CONCLUSIONS: Pure laparoscopic RAS is a feasible operative procedure in patients with tumors located in hepatic segments 5/8.
Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia/métodos , Laparoscopia/métodos , Neoplasias Hepáticas/cirurgia , Carcinoma Hepatocelular/diagnóstico por imagem , Veias Hepáticas/diagnóstico por imagem , Veias Hepáticas/cirurgia , Humanos , Complicações Intraoperatórias , Neoplasias Hepáticas/diagnóstico por imagem , Período Pós-Operatório , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Laparoscopic major hepatectomy remains a challenging procedure [1, 2]. In the case of giant tumors in the right liver, conventional approach (complete mobilization of the right liver before parenchymal transection) could be dangerous during mobilization because of large volume and weight [3, 4]. We present the case of a pure laparoscopic right hepatectomy for a giant hemangioma using an anterior approach. METHODS: We achieved the informed consent with this patient and approved by the Ethics Committee of the Asan Medical Center. Giant hemangioma (13 × 11 × 14 cm) was located in right liver. After glissonean approach [5], Pringle maneuver was performed during the hepatic parenchymal transection. For the transection, the Cavitron Ultrasonic Surgical Aspirator was used. Small hepatic vein branches along the middle hepatic vein and small glissonean pedicles were sealed and divided with a THUNDERBEATTM (Olympus), which is the device with integration of both bipolar and ultrasonic energies delivered simultaneously. iDriveTM Ultra Powered Stapling device (Medtronic) was used for division of right glissonean pedicle and large hepatic veins. Hemangioma was removed through the lower abdominal transverse incision using the endo-bag. This technique has the advantage of avoiding excessive bleeding caused by avulsion of the hepatic vein and caval branches, iatrogenic tumor rupture [3]. RESULTS: By means of the anterior approach, pure laparoscopic right hepatectomy was performed successfully without intraoperative complications and transfusions. The operation time was 202 min, and the estimated blood loss was less than 150 ml. On postoperative day 3, computed tomographic scan showed no pathological findings. The patient was discharged on postoperative day 5 without complications. Laparoscopic approach has good results because of the view with magnification enabling meticulous hemostasis and the small wounds that give patients less pain [6, 7]. CONCLUSIONS: The authors recommend that the laparoscopic anterior approach is safe and feasible for right hepatectomy, even for giant tumors.
Assuntos
Hemangioma/cirurgia , Hepatectomia/métodos , Laparoscopia/métodos , Neoplasias Hepáticas/cirurgia , Veias Hepáticas/cirurgia , Humanos , Resultado do TratamentoAssuntos
Sarcoma de Kaposi , Tinha , Sarcoma de Kaposi/diagnóstico , Tinha/diagnóstico , TrichophytonRESUMO
Stem cells are poorly permissive to non-viral gene transfection reagents. In this study, we explored the possibility of improving gene delivery into human embryonic (hESC) and mesenchymal (hMSC) stem cells by synergizing the activity of a cell-binding ligand with a polymer that releases nucleic acids in a cytoplasm-responsive manner. A 29 amino acid long peptide, RVG, targeting the nicotinic acetylcholine receptor (nAchR) was identified to bind both hMSC and H9-derived hESC. Conjugating RVG to a redox-sensitive biodegradable dendrimer-type arginine-grafted polymer (PAM-ABP) enabled nanoparticle formation with plasmid DNA without altering the environment-sensitive DNA release property and favorable toxicity profile of the parent polymer. Importantly, RVG-PAM-ABP quantitatively enhanced transfection into both hMSC and hESC compared to commercial transfection reagents like Lipofectamine 2000 and Fugene. â¼60% and 50% of hMSC and hESC were respectively transfected, and at increased levels on a per cell basis, without affecting pluripotency marker expression. RVG-PAM-ABP is thus a novel bioreducible, biocompatible, non-toxic, synthetic gene delivery system for nAchR-expressing stem cells. Our data also demonstrates that a cell-binding ligand like RVG can cooperate with a gene delivery system like PAM-ABP to enable transfection of poorly-permissive cells.
Assuntos
Materiais Biocompatíveis/química , Técnicas de Transferência de Genes , Vetores Genéticos/química , Peptídeos/química , Células-Tronco/citologia , Animais , Arginina/química , Citoplasma/metabolismo , DNA/química , Células-Tronco Embrionárias/citologia , Fibroblastos/metabolismo , Citometria de Fluxo , Proteínas de Fluorescência Verde/química , Humanos , Ligantes , Lipídeos/química , Células-Tronco Mesenquimais/citologia , Camundongos , Oxirredução , Fenótipo , Plasmídeos/metabolismo , Polímeros/química , Receptores Nicotínicos/metabolismo , TransfecçãoRESUMO
PURPOSE: The significant advantages of robotic surgery have expanded the scope of surgical procedures that can be performed through minimally invasive techniques. The aim of this study was to compare the perioperative outcomes between robotic and laparoscopic liver surgeries at a single center. METHODS: From July 2007 to October 2011, a total of 206 patients underwent laparoscopic or robotic liver surgery at the Asan Medical Center, Seoul, Korea. We compared the surgical outcomes between robotic liver surgery and laparoscopic liver surgery during the same period. Only patients who underwent left hemihepatectomy or left lateral sectionectomy were included in this study. RESULTS: The robotic group consisted of 13 patients who underwent robotic liver resection including 10 left lateral sectionectomies and three left hemihepatectomies. The laparoscopic group consisted of 17 patients who underwent laparoscopic liver resection during the same period including six left lateral sectionectomies and 11 left hemihepatectomies. The groups were similar with regard to age, gender, tumor type, and tumor size. There were no significant differences in perioperative outcome such as operative time, intraoperative blood loss, postoperative liver function tests, complication rate, and hospital stay between robotic liver resection and laparoscopic liver resection. However, the medical cost was higher in the robotic group. CONCLUSIONS: Robotic liver resection is a safe and feasible option for liver resection in experienced hands. The authors suggest that since the robotic surgical system provides sophisticated advantages, the retrenchment of medical cost for the robotic system in addition to refining its liver transection tool may substantially increase its application in clinical practice in the near future.
Assuntos
Hepatectomia/métodos , Laparoscopia/métodos , Hepatopatias/cirurgia , Robótica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
Multi-functional polymer nanoparticles have been widely utilized to improve cellular uptake and enhance therapeutic efficacy. In this study, it is hypothesized that the cellular uptake of poly(D,L-lactide-co-glycolide) (PLG) nanoparticles loaded with calcium carbonate minerals into adipocytes can be improved by covalent modification with nona-arginine (R9 ) peptide. It is further hypothesized that the internalization mechanism of R9 -modified PLG nanoparticles by adipocytes may be contingent on the concentration of R9 peptide present in the nanoparticles. R9 -modified PLG nanoparticles followed the direct penetration mechanism when the concentration of R9 peptide in the nanoparticles reached 38 µM. Notably, macropinocytosis is the major endocytic mechanism when the R9 peptide concentration is ≤ 26 µM. The endocytic uptake of the nanoparticles effectively generated carbon dioxide gas at an endosomal pH, resulting in significant adipocytolytic effects in vitro, which are further supported by the findings in an obese mouse model induced by high-fat diet. Gas-generating PLG nanoparticles, modified with R9 peptide, demonstrated localized reduction of adipose tissue (reduction of 13.1%) after subcutaneous injection without significant side effects. These findings highlight the potential of multi-functional polymer nanoparticles for the development of effective and targeted fat reduction techniques, addressing both health and cosmetic considerations.
Assuntos
Nanopartículas , Polímeros , Camundongos , Animais , Polímeros/farmacologia , Peptídeos/farmacologia , Carbonato de Cálcio , Adipócitos , Nanopartículas/uso terapêuticoRESUMO
BACKGROUND: Bullous pilomatricoma is a rare variant of pilomatricoma. As it has been published in sporadic case reports, a limited understanding of its clinicopathological characteristics restricts its effective diagnosis and treatment. OBJECTIVES: This study aimed to analyze the clinicopathological and immunohistochemical characteristics of bullous pilomatricoma to better understand the bullous transformation of pilomatricoma. METHODS: The authors conducted a retrospective study of 12 patients with bullous pilomatricoma and compared their clinical, histopathological, and immunohistochemical data with those of patients with ordinary pilomatricoma. RESULTS: Bullous pilomatricoma showed no sex preference, with a mean onset age of 31.2 years. The common sites were the upper extremities and trunk. Bullous pilomatricoma had a shorter disease duration, a larger diameter, and a greater tendency to increase in size than those of ordinary pilomatricoma. Histopathologically, bullous pilomatricoma had a shorter duration, lesser calcification, more mitotic figures, and distinct dermal features from those of ordinary pilomatricoma. Immunohistochemically, the expression of Matrix Metalloprotease (MMP)-2, MMP-9, vascular endothelial growth factor receptor-3 (VEGFR-3), and VEGF-C was elevated. STUDY LIMITATIONS: The study was retrospective, and the sample size was small. CONCLUSION: The distinctive features of bullous pilomatricoma potentially result from dermal changes associated with the release of angiogenic factors and proteolytic enzymes. This comprehensive analysis provides novel insights into the clinical features and pathogenesis of bullous pilomatricoma.
Assuntos
Doenças do Cabelo , Imuno-Histoquímica , Pilomatrixoma , Neoplasias Cutâneas , Humanos , Pilomatrixoma/patologia , Estudos Retrospectivos , Feminino , Masculino , Adulto , Neoplasias Cutâneas/patologia , Doenças do Cabelo/patologia , Pessoa de Meia-Idade , Adulto Jovem , Adolescente , CriançaRESUMO
Interest in multifunctional polymer nanoparticles for targeted delivery of anti-cancer drugs has grown significantly in recent years. In this study, tumor-targeting echogenic polymer micelles were prepared from poly(ethylene glycol) methyl ether-alkyl carbonate (mPEG-AC) derivatives, and their potential in cancer therapy was assessed. Various mPEG derivatives with carbonate linkages were synthesized via an alkyl halide reaction between mPEG and alkyl chloroformate. Micelle formation using polymer amphiphiles in aqueous media and the subsequent carbon dioxide (CO2) gas generation from the micelles was confirmed. Their ability to target neuroblastoma was substantially enhanced by incorporating the rabies virus glycoprotein (RVG) peptide. RVG-modified gas-generating micelles significantly inhibited tumor growth in a tumor-bearing mouse model owing to CO2 gas generation within tumor cells and resultant cytolytic effects, showing minimal side effects. The development of multifunctional polymer micelles may offer a promising therapeutic approach for various diseases, including cancer.
Assuntos
Formiatos , Neuroblastoma , Polímeros , Animais , Camundongos , Micelas , Dióxido de Carbono , Polietilenoglicóis , Peptídeos , CarbonatosRESUMO
Age-related macular degeneration (AMD), characterized by macular retinal degeneration, poses a significant health concern due to the lack of effective treatments for prevalent dry AMD. The progression of AMD is closely linked to reactive oxygen species and Fas signaling, emphasizing the need for targeted interventions. In this study, we utilized a NaIO3-induced retinal degeneration mouse model to assess the efficacy of Fas-blocking peptide (FBP). Intravitreal administration of FBP successfully suppressed Fas-mediated inflammation and apoptosis, effectively arresting AMD progression in mice. We developed a 6R-conjugated FBP (6R-FBP) for eye drop administration. 6R-FBP, administered as an eye drop, reached the retinal region, attenuating degeneration by modulating the expression of inflammatory cytokines and blocking Fas-mediated apoptosis in rodent and rabbit NaIO3-induced retinal degeneration models to address practical concerns. Intravitreal FBP and 6R-FBP eye drops effectively reduced retinal degeneration and improved retinal thickness in rodent and rabbit models. This study highlights the therapeutic potential of FBP, particularly 6R-FBP as an eye drop, in inhibiting Fas-mediated cell signaling and protecting against retinal cell death and inflammation in dry AMD. Future investigations should explore the translational prospects of this approach in primates with eye structures comparable to those of humans.
Assuntos
Degeneração Macular , Degeneração Retiniana , Humanos , Camundongos , Animais , Coelhos , Soluções Oftálmicas/uso terapêutico , Degeneração Macular/metabolismo , Peptídeos/uso terapêutico , InflamaçãoRESUMO
Amyloid-ß (Aß) peptide aggregation in the brain is a key factor in Alzheimer's disease. However, direct inhibition of ß-secretase or γ-secretase proves ineffective in reducing Aß accumulation and improving cognition in Alzheimer's. Recent findings suggest that inhibiting gamma-secretase activating protein (GSAP) can decrease Aß generation without affecting crucial γ-secretase substrates. Dimerization of Lep9R3LC (diLep9R3LC) was confirmed by Ellman's test. The peptide-small interfering RNA (siRNA) complex ratio, particle size, and surface charge were analyzed using electrophoretic mobility shift assay, and dynamic light scattering, respectively. In a 3xTg mice model of Alzheimer's disease, diLep9R3LC:siRNA complexes were intravenously administered twice a week for 8 weeks. Assessments included gene silencing, protein expression, and behavioral improvement using reverse transcription polymerase chain reaction, quantitative polymerase chain reaction, western blotting, Y-maze, and object recognition tests. The efficacy of Lep9R3LC dimerization was ~80% after a 3-d reaction by Ellman's test. In N2a cells, diLep9R3LC:siGSAP complexes achieved ~70% silencing at 48 h posttransfection. In 7-month-old male 3xTg mice, GSAP knockdown was ~30% in the cortex and ~50% in the hippocampus. The behavior improved in mice treated with diLep9R3LC:siGSAP complexes, showing a 60% increase in entries and an 80% increase object recognition. A novel dipeptide, diLep9R3LC, complexed with siRNA targeting GSAP (siGSAP), efficiently delivers siRNA to the mouse brain, targeting the hippocampus. The treatment inhibits Aß accumulation, reduces GSK-3ß-associated with tau hyperphosphorylation, and improves Alzheimer's behavior. Our findings highlight diLep9R3LC:siGSAP's potential for Alzheimer's and as a siRNA carrier for central nervous system-related diseases.
RESUMO
Ischemic stroke-induced neuronal cell death leads to the permanent impairment of brain function. The Fas-mediating extrinsic apoptosis pathway and the cytochrome c-mediating intrinsic apoptosis pathway are two major molecular mechanisms contributing to neuronal injury in ischemic stroke. In this study, we employed a Fas-blocking peptide (FBP) coupled with a positively charged nona-arginine peptide (9R) to form a complex with negatively charged siRNA targeting Bax (FBP9R/siBax). This complex is specifically designed to deliver siRNA to Fas-expressing ischemic brain cells. This complex enables the targeted inhibition of Fas-mediating extrinsic apoptosis pathways and cytochrome c-mediating intrinsic apoptosis pathways. Specifically, the FBP targets the Fas/Fas ligand signaling, while siBax targets Bax involved in mitochondria disruption in the intrinsic pathway. The FBP9R carrier system enables the delivery of functional siRNA to hypoxic cells expressing the Fas receptor on their surface-a finding validated through qPCR and confocal microscopy analyses. Through intranasal (IN) administration of FBP9R/siCy5 to middle cerebral artery occlusion (MCAO) ischemic rat models, brain imaging revealed the complex specifically localized to the Fas-expressing infarcted region but did not localize in the non-infarcted region of the brain. A single IN administration of FBP9R/siBax demonstrated a significant reduction in neuronal cell death by effectively inhibiting Fas signaling and preventing the release of cytochrome c. The targeted delivery of FBP9R/siBax represents a promising alternative strategy for the treatment of brain ischemia.