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1.
Vaccines (Basel) ; 12(6)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38932378

RESUMO

Oligodeoxynucleotides (ODNs) containing unmethylated cytosine-phosphate-guanosine (CpG) motifs are readily recognized by Toll-like receptor 9 on immune cells, trigger an immunomodulatory cascade, induce a Th1 -biased immune milieu, and have great potential as an adjuvant in cancer vaccines. In this study, a green one-step synthesis process was adopted to prepare an amino-rich metal-organic nanoplatform (FN). The synthesized FN nanoplatform can simultaneously and effectively load model tumor antigens (OVA)/autologous tumor antigens (dLLC) and immunostimulatory CpG ODNs with an unmodified PD backbone and a guanine quadruplex structure to obtain various cancer vaccines. The FN nanoplatform and immunostimulatory CpG ODNs generate synergistic effects to enhance the immunogenicity of different antigens and inhibit the growth of established and distant tumors in both the murine E.G7-OVA lymphoma model and the murine Lewis lung carcinoma model. In the E.G7-OVA lymphoma model, vaccination efficiently increases the CD4+, CD8+, and tetramer+CD8+ T cell populations in the spleens. In the Lewis lung carcinoma model, vaccination efficiently increases the CD3+CD4+ and CD3+CD8+ T cell populations in the spleens and CD3+CD8+, CD3-CD8+, and CD11b+CD80+ cell populations in the tumors, suggesting the alteration of tumor microenvironments from cold to hot tumors.

2.
Artigo em Inglês | MEDLINE | ID: mdl-37930044

RESUMO

OBJECTIVES: The use of bone wax (BW) is controversial for sternal haemostasis because it increases the risk of wound infection and inhibits bone healing. We developed new waxy bone haemostatic agents made from biodegradable polymers containing peptides and evaluated them using rabbit models. METHODS: We designed 2 types of waxy bone haemostatic agents: peptide wax (PW) and non-peptide wax (NPW), which used poly(ε-caprolactone)-based biodegradable polymers with or without an osteogenesis-enhancing peptide, respectively. Rabbits were randomly divided into 4 groups based on treatment with BW, NPW, PW or no treatment. In a tibial defect model, the bleeding amount was measured and bone healing was evaluated by micro-computed tomography over 16 weeks. Bone healing in a median sternotomy model was assessed for 2 weeks using X-ray, micro-computed tomography, histological examination and flexural strength testing. RESULTS: The textures of PW and NPW (n = 12 each) were similar to that of BW and achieved a comparable degree of haemostasis. The crevice area of the sternal fracture line in the BW group was significantly larger than that in other groups (n = 10 each). The PW group demonstrated the strongest sternal flexural strength (n = 10), with complete tibial healing at 16 weeks. No groups exhibited wound infection, including osteomyelitis. CONCLUSIONS: Waxy biodegradable haemostatic agents showed satisfactory results in haemostasis and bone healing in rabbit models and may be an effective alternative to BW.

3.
J Control Release ; 363: 550-561, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37804880

RESUMO

Anticancer drug resistance invariably emerges and poses a significant barrier to curative therapy for various breast cancers. This results in a lack of satisfactory therapeutic medicine for cancer treatment. Herein, a universal vector system for drug-resistance breast cancer was designed to meet the needs of reversed multidrug resistance, thermo-chemotherapy, and long-term drug release behavior. The vector system comprises polycaprolactone (PCL) nanofiber mesh and magnetic nanoparticles (MNPs). PCL has excellent biocompatibility and electrospinning performance. In this study, MNPs were tailored to be thermogenic in response to an alternating magnetic field (AMF). PCL nanofiber can deliver various chemotherapy drugs, and suitable MNPs encapsulated in the nanofiber can generate hyperthermia and synergistic effect with those chemotherapy drugs. Therefore, a more personalized treatment system can be developed for different breast malignancies. In addition, the PCL nanofiber mesh (NFM) enables sustained release of the drugs for up two months, avoiding the burden on patients caused by repeated administration. Through model drugs doxorubicin (DOX) and chemosensitizers curcumin (CUR), we systematically verified the therapeutic effect of DOX-resistance breast cancer and inhibition of tumor generation in vivo. These findings represent a multifaceted platform of importance for validating strategic reversed MDR in pursuit of promoted thermo-chemotherapeutic outcomes. More importantly, the low cost and excellent safety and efficacy of this nanofiber mesh demonstrate that this can be customized multi-function vector system may be a promising candidate for refractory cancer therapy in clinical.


Assuntos
Neoplasias da Mama , Curcumina , Hipertermia Induzida , Nanopartículas , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Hipertermia Induzida/métodos , Doxorrubicina , Portadores de Fármacos/uso terapêutico , Curcumina/uso terapêutico , Linhagem Celular Tumoral
4.
Soft Matter ; 19(33): 6224-6233, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37493066

RESUMO

Here, we designed enzymatically degradable hydrogels with tunable mesh sizes and crosslinking points to evaluate the effectiveness of network structure estimations in predicting dynamic mechanical properties and cargo retention or release. Poly(ethylene glycol) (PEG) hydrogels were prepared through a thiol-ene click reaction between four- or eight-arm PEG functionalized with vinyl sulfone and cysteine residues of collagenase-degradable peptides to create well-defined, homogenous, and robust materials with a range of mesh sizes estimated from the elasticity theory or Flory-Rehner theory. Time-dependent changes in mechanical properties associated with hydrogel degradation, i.e., dynamics of storage modulus, which is determined by the relationship between the hydrogel mesh and enzyme sizes, were characterized. The shear modulus G' decreased by enzyme addition, and the degradation rate decreased with the initial crosslinking density of the hydrogel. The degradation rate could also be controlled with the reactivity of peptide sequences against collagenase. With these findings, the retention and release of FITC-dextran were successfully controlled by tuning the mesh size and degradability of the hydrogel. This report provides useful insights for designing hydrogels as cell scaffolds or functional molecular delivery matrices with tunable dynamic mechanical properties and the resulting release of loaded drugs or proteins.


Assuntos
Hidrogéis , Polietilenoglicóis , Hidrogéis/química , Polietilenoglicóis/química , Peptídeos/química , Elasticidade
5.
Nanomaterials (Basel) ; 13(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36770373

RESUMO

This study aims to propose a new treatment model for glioblastoma (GBM). The combination of chemotherapy, molecular targeted therapy and radiotherapy has been achieved in a highly simultaneous manner through the application of a safe, non-toxic, locally sustained drug-releasing composite Nanofiber mesh (NFM). The NFM consisted of biodegradable poly(ε-caprolactone) with temozolomide (TMZ) and 17-allylamino-17-demethoxygeldanamycin (17AAG), which was used in radiation treatment. TMZ and 17AAG combination showed a synergistic cytotoxicity effect in the T98G cell model. TMZ and 17AAG induced a radiation-sensitization effect, respectively. The NFM containing 17AAG or TMZ, known as 17AAG-NFM and TMZ-NFM, enabled cumulative drug release of 34.1% and 39.7% within 35 days. Moreover, 17AAG+TMZ-NFM containing both drugs revealed a synergistic effect in relation to the NFM of a single agent. When combined with radiation, 17AAG+TMZ-NFM induced in an extremely powerful cytotoxic effect. These results confirmed the application of NFM can simultaneously allow multiple treatments to T98G cells. Each modality achieved a significant synergistic effect with the other, leading to a cascading amplification of the therapeutic effect. Due to the superior advantage of sustained drug release over a long period of time, NFM has the promise of clinically addressing the challenge of high recurrence of GBM post-operatively.

6.
Front Immunol ; 14: 1328379, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38259474

RESUMO

Background: Considering the diversity of tumors, it is of great significance to develop a simple, effective, and low-cost method to prepare personalized cancer vaccines. Methods: In this study, a facile one-pot synthetic route was developed to prepare cancer vaccines using model antigen or autologous tumor antigens based on the coordination interaction between Fe3+ ions and endogenous fumarate ligands. Results: Herein, Fe-based metal organic framework can effectively encapsulate tumor antigens with high loading efficiency more than 80%, and act as both delivery system and adjuvants for tumor antigens. By adjusting the synthesis parameters, the obtained cancer vaccines are easily tailored from microscale rod-like morphology with lengths of about 0.8 µm (OVA-ML) to nanoscale morphology with sizes of about 50~80 nm (OVA-MS). When cocultured with antigen-presenting cells, nanoscale cancer vaccines more effectively enhance antigen uptake and Th1 cytokine secretion than microscale ones. Nanoscale cancer vaccines (OVA-MS, dLLC-MS) more effectively enhance lymph node targeting and cross-presentation of tumor antigens, mount antitumor immunity, and inhibit the growth of established tumor in tumor-bearing mice, compared with microscale cancer vaccines (OVA-ML, dLLC-ML) and free tumor antigens. Conclusions: Our work paves the ways for a facile, rapid, and low-cost preparation approach for personalized cancer vaccines.


Assuntos
Vacinas Anticâncer , Estruturas Metalorgânicas , Neoplasias , Animais , Camundongos , Autoantígenos , Ferro , Antígenos de Neoplasias , Neoplasias/terapia
7.
Int J Mol Sci ; 23(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36498966

RESUMO

The reactivating of disseminated dormant breast cancer cells in a soft viscoelastic matrix is mostly correlated with metastasis. Metastasis occurs due to rapid stress relaxation owing to matrix remodeling. Here, we demonstrate the possibility of promoting the permanent cell cycle arrest of breast cancer cells on a viscoelastic liquid substrate. By controlling the molecular weight of the hydrophobic molten polymer, poly(ε-caprolactone-co-D,L-lactide) within 35-63 g/mol, this study highlights that MCF7 cells can sense a 1000 times narrower relaxation time range (80-290 ms) compared to other studies by using a crosslinked hydrogel system. We propose that the rapid bulk relaxation response of the substrate promotes more reactive oxygen species generation in the formed semi-3D multicellular aggregates of breast cancer cells. Our finding sheds light on the potential role of bulk stress relaxation in a viscous-dominant viscoelastic matrix in controlling the cell cycle arrest depth of breast cancer cells.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Hidrogéis/química , Viscosidade , Pontos de Checagem do Ciclo Celular , Estresse Oxidativo
8.
Front Bioeng Biotechnol ; 10: 1046147, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406225

RESUMO

We developed a smart nanofiber mesh (SNM) with anticancer abilities as well as injectability and fast recovery from irregular to non-compressible shapes. The mesh can be injected at the tumor site to modulate and control anticancer effects by loading the chemotherapeutic drug, paclitaxel (PTX), as well as magnetic nanoparticles (MNPs). The storage modulus of the mesh decreases when applied with a certain shear strain, and the mesh can pass through a 14-gauge needle. Moreover, the fibrous morphology is maintained even after injection. In heat-generation measurements, the mesh achieved an effective temperature of mild hyperthermia (41-43°C) within 5 min of exposure to alternating magnetic field (AMF) irradiation. An electrospinning method was employed to fabricate the mesh using a copolymer of N-isopropylacrylamide (NIPAAm) and N-hydroxyethyl acrylamide (HMAAm), whose phase transition temperature was adjusted to a mildly hyperthermic temperature range. Pplyvinyl alcohol (PVA) was also incorporated to add shear-thinning property to the interactions between polymer chains derived from hydrogen bonding, The "on-off" switchable release of PTX from the mesh was detected by the drug release test. Approximately 73% of loaded PTX was released from the mesh after eight cycles, whereas only a tiny amount of PTX was released during the cooling phase. Furthermore, hyperthermia combined with chemotherapy after exposure to an AMF showed significantly reduced cancer cell survival compared to the control group. Subsequent investigations have proven that a new injectable local hyperthermia chemotherapy platform could be developed for cancer treatment using this SNM.

9.
Nanomaterials (Basel) ; 12(8)2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35458072

RESUMO

Lenvatinib has a high response rate in unresectable advanced hepatocellular carcinoma (HCC). In this study, we investigated whether lenvatinib-incorporating poly(ε-caprolactone) sheets (lenvatinib sheets) as a drug delivery system (DDS) exerted antitumor effects in a murine HCC model. The lenvatinib sheets were designed for sustained release of approximately 1 mg lenvatinib for 14 days. For 14 days, 1 mg lenvatinib was orally administered to mice. Then, we compared the antitumor effects of lenvatinib sheets with those of oral lenvatinib. The tumor volume, body weight, and serum lenvatinib level were measured for 14 days. A peritoneal dissemination model was established to examine the survival prolongation effect of the lenvatinib sheets. Tumor growth was significantly inhibited in the lenvatinib sheet group compared with that in the no treatment and oral groups. The antitumor effect was significantly higher in the lenvatinib sheet group. Regardless of the insertion site, the serum lenvatinib levels were maintained and showed similar antitumor effects. The mitotic index was significantly inhibited in the lenvatinib sheet group compared with that in the control group. Furthermore, lenvatinib sheets improved the 30-day survival. Lenvatinib sheets showed sufficient antitumor effects and may serve as an effective novel DDS for advanced HCC.

10.
Adv Healthc Mater ; 11(13): e2200050, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35385611

RESUMO

Shape-memory polymers (SMPs) are promising materials in numerous emerging biomedical applications owing to their unique shape-memory characteristics. However, simultaneous realization of high strength, toughness, stretchability while maintaining high shape fixity (Rf ) and shape recovery ratio (Rr ) remains a challenge that hinders their practical applications. Herein, a novel shape-memory polymeric string (SMP string) that is ultra-stretchable (up to 1570%), strong (up to 345 MPa), tough (up to 237.9 MJ m-3 ), and highly recoverable (Rf averagely above 99.5%, Rr averagely above 99.1%) through a facile approach fabricated solely by tetra-branched poly(ε-caprolactone) (PCL) is reported. Notably, the shape-memory contraction force (up to 7.97 N) of this SMP string is customizable with the manipulation of their energy storage capacity by adjusting the string thickness and stretchability. In addition, this SMP string displays a controllable shape-memory response time and demonstrates excellent shape-memory-induced contraction effect against both rigid silicone tubes and porcine carotids. This novel SMP string is envisioned to be applied in the contraction of blood vessels and resolves the difficulties in the restriction of blood flow in minimally invasive surgeries such as fetoscopic surgery of sacrococcygeal teratoma (SCT).


Assuntos
Polímeros , Teratoma , Animais , Fenômenos Mecânicos , Suínos , Teratoma/cirurgia
12.
Sci Rep ; 11(1): 20409, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34650081

RESUMO

This study aimed to develop a poly-ε-caprolactone (PCL) material that has a low melting point while maintaining the deformation ability. The new PCL (abbreviated as 4b45/2b20) was fabricated by mixing two types of PCL with different molecular weights, numbers of branches, and physical properties. To investigate the melting point, crystallization temperature, elastic modulus, and elongation at break for 4b45/2b20 and three commercially available masks, differential scanning calorimetry and tensile tests were performed. The melting point of 4b45/2b20 was 46.0 °C, and that of the commercially available masks was approximately 56.0 °C (55.7 °C-56.5 °C). The elastic modulus at 60 °C of 4b45/2b20 was significantly lower than the commercially available masks (1.1 ± 0.3 MPa and 46.3 ± 5.4 MPa, p = 0.0357). In addition, the elongation at break of 4b45/2b20 were significantly larger than the commercially available masks (275.2 ± 25.0% and 216.0 ± 15.2%, p = 0.0347). The crystallization temperature of 4b45/2b20 (22.1 °C) was clinically acceptable and no significant difference was found in the elastic modulus at 23 °C (253.7 ± 24.3 MPa and 282.0 ± 44.3 MPa, p = 0.4). As a shape memory-based thermoset material, 4b45/2b20 has a low melting point and large deformation ability. In addition, the crystallization temperature and strength are within the clinically acceptable standards. Because masks made using the new PCL material are formed with less pressure on the face than commercially available masks, it is a promising material for making a radiotherapy mask that can reduce the burden on patients.


Assuntos
Caproatos , Lactonas , Máscaras , Poliésteres , Radioterapia/instrumentação , Caproatos/química , Cristalização , Humanos , Lactonas/química , Poliésteres/química , Resistência à Tração , Temperatura de Transição
13.
Biomater Sci ; 9(20): 6957-6965, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34546257

RESUMO

This paper proposes a shape-memory balloon (SMB) to improve bone cement injection efficiency and postoperative thermo/chemotherapy for bone tumors. The SMB consists of biodegradable poly(ε-caprolactone) (PCL), an anticancer drug (doxorubicin, DOX), and heat-generating magnetic nanoparticles (MNPs). The balloon shape is fabricated in a mold by crosslinking PCL macromonomers with DOX and MNPs. The mechanical properties and shape-transition temperature (approximately 40 °C) of the SMB are modulated by adjusting the molecular weight of PCL and the crosslinking density. This allows safe inflation at the affected site with a 400% expansion rate by simple blow molding. The expanded shape is temporarily memorized at 37 °C, and the computed tomography image shows that the bone cement is successfully injected without extra pressure or leakage. The SMB releases DOX for over 4 weeks, allowing a prolonged effect at the local site. The local dosing is constant as the medication is continuously released, demonstrating an ON-OFF switchable heating/cooling response to alternating magnetic field irradiation. In vitro cytotoxic studies have demonstrated that heat generation/drug release and only drug release from the balloon kill approximately 99% and 60% of human osteosarcoma cells, respectively. The proposed SMB is promising in postoperative local thermo/chemotherapy for bone tumors.


Assuntos
Osteossarcoma , Poliésteres , Doxorrubicina , Portadores de Fármacos , Humanos , Micelas , Osteossarcoma/tratamento farmacológico
14.
Sci Technol Adv Mater ; 22(1): 522-531, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34220340

RESUMO

We reports a novel thermally enhanced drug release system synthesized via a dynamic Diels-Alder (DA) reaction to develop chemotherapy for pancreatic cancer. The anticancer prodrug was designed by tethering gemcitabine (GEM) to poly(furfuryl methacrylate) (PFMA) via N-(3-maleimidopropionyloxy)succinimide as a linker by DA reaction (PFMA-L-GEM). The conversion rate of the DA reaction was found to be approximately 60% at room temperature for 120 h. The reversible deconstruction of the DA covalent bond in retro Diels-Alder (rDA) reaction was confirmed by proton nuclear magnetic resonance, and the reaction was significantly accelerated at 90 °C. A PFMA-LGEM film containing magnetic nanoparticles (MNPs) was prepared for thermally enhanced release of the drug via the rDA reaction. Drug release was initiated by heating MNPs by alternating magnetic field. This enables local heating within the film above the rDA reaction temperature while maintaining a constant surrounding medium temperature. The MNPs/PFMA-L-GEM film decreased the viability of pancreatic cancer cells by 49% over 24 h. Our results suggest that DA/rDA-based thermally enhanced drug release systems can serve as a local drug release platform and deliver the target drug within locally heated tissue, thereby improving the therapeutic efficiency and overcoming the side effects of conventional drugs used to treat pancreatic cancer.

15.
Biomed Res Int ; 2021: 6678913, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33855079

RESUMO

Hepatic fibrosis is a progressive disease with serious clinical complications that arise from abnormal propagation and activation of multiple inflammatory pathways. Nilotinib is an oral tyrosine kinase inhibitor with antifibrotic activity. Mesenchymal stem cells (MSCs) are blank cells and can differentiate into specific cell types. They have the potential to repair and regenerate cells. MSCs have a special paracrine fashion where they produce special exosomes, microvesicles, and cytokines like IL-6, transforming growth factor-beta (TGF-ß), and HGF as well as hepatic stellate cell suppressors. This paracrine fashion can decrease collagen deposition, enhance antifibrotic, anti-inflammatory, and angiogenic activity in vitro and in vivo. In our study, the rat's hepatic stellate cells (HSCs) in addition to different normal cell lines were treated with Nilotinib alone and in combination with liver mesenchymal stem cells conditioned medium (LMSCs-CM) for 24 h. Mono and combined therapy antifibrotic and cytotoxicity effects were evaluated using different parameters including α-SMA, cytochrome c, P53 expression, collagen deposition, DNA content, oxidative stress parameters, cell viability, and apoptosis by flow cytometry analysis. Our results showed that Nilotinib and LMSCs-CM in combination had a significantly potent antifibrotic and anti-inflammatory effect on activated hepatic stellate cells than Nilotinib alone; otherwise, this combination showed the best safety with minimal cytotoxicity on different normal cell lines.


Assuntos
Meios de Cultivo Condicionados/farmacologia , Células Estreladas do Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Células-Tronco Mesenquimais/química , Pirimidinas/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colágeno/metabolismo , Terapia Combinada , Citocromos c/metabolismo , DNA/metabolismo , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Concentração Inibidora 50 , Cirrose Hepática/patologia , Masculino , Modelos Biológicos , Estresse Oxidativo/efeitos dos fármacos , Pirimidinas/farmacologia , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo
16.
Int J Mol Sci ; 22(5)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802613

RESUMO

This study demonstrates the rational fabrication of a magnetic composite nanofiber mesh that can achieve mutual synergy of hyperthermia, chemotherapy, and thermo-molecularly targeted therapy for highly potent therapeutic effects. The nanofiber is composed of biodegradable poly(ε-caprolactone) with doxorubicin, magnetic nanoparticles, and 17-allylamino-17-demethoxygeldanamycin. The nanofiber exhibits distinct hyperthermia, owing to the presence of magnetic nanoparticles upon exposure of the mesh to an alternating magnetic field, which causes heat-induced cell killing as well as enhanced chemotherapeutic efficiency of doxorubicin. The effectiveness of hyperthermia is further enhanced through the inhibition of heat shock protein activity after hyperthermia by releasing the inhibitor 17-allylamino-17-demethoxygeldanamycin. These findings represent a smart nanofiber system for potent cancer therapy and may provide a new approach for the development of localized medication delivery.


Assuntos
Benzoquinonas/farmacologia , Preparações de Ação Retardada/farmacologia , Doxorrubicina/farmacologia , Hipertermia/tratamento farmacológico , Lactamas Macrocíclicas/farmacologia , Nanofibras/química , Neoplasias/tratamento farmacológico , Benzoquinonas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/química , Doxorrubicina/química , Liberação Controlada de Fármacos , Sinergismo Farmacológico , Compostos Férricos/química , Humanos , Lactamas Macrocíclicas/química , Células MCF-7 , Magnetismo/métodos , Nanopartículas de Magnetita/química
17.
Oxid Med Cell Longev ; 2021: 8833467, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33623636

RESUMO

Type 2 diabetes mellitus (T2DM) is mainly characterized by insulin resistance and impaired insulin secretion, which cannot be reversed with existing therapeutic strategies. Using mesenchymal stem cells (MSCs), cell-based therapy has been demonstrated in displaying therapeutic effects in T2DM for their self-renewable, differentiation potential, and immunosuppressive properties and higher levels of angiogenic factors. Stem cell therapies are complicated and have a serious adverse effect including tumor formation and immunogenicity, while using mesenchymal stem cell-conditioned media (MSC-CM) significantly reduces stem cell risk, maintaining efficacy and showing significantly higher levels of growth factors, cytokines, and angiogenic factors that stimulate angiogenesis and promote fracture healing in diabetes. In the present study, we investigated the therapeutic potential of the liver and adipose MSC-CM in diabetic endothelial dysfunction compared with standard insulin therapy. Fifty adult male Sprague Dawley rats were divided equally into 5 groups as follows: control, diabetic, diabetic+insulin, diabetic+liver MSC-CM, and diabetic+adipose MSC-CM; all treatments continued for 4 weeks. Finally, we observed that liver MSC-CM therapy had the most apparent improvement in levels of blood glucose; HbA1c; AGEs; lipid panel (cholesterol, TG, LDL, HDL, and total lipids); renal function (urea, uric acid, creatinine, and total protein); liver function (AST, ALT, ALP, bilirubin, and albumin); CPK; C-peptide; HO-1; inflammatory markers including IL-6, TNF-α, and CRP; growth factors (liver and serum IGF-1); amylase; histopathological changes; pancreatic cell oxidative stress; and antioxidant markers (MDA, GSH, ROS, CAT, SOD, HO-1, and XO) toward the normal levels compared with insulin and adipose MSCs-CM. Moreover, both the liver and adipose MSC-CM relieved the hyperglycemic status by improving pancreatic islet ß cell regeneration, promoting the conversion of alpha cells to beta cells, reducing insulin resistance, and protecting pancreatic tissues against oxidative stress-induced injury as well as possessing the ability to modulate immunity and angiogenesis. These results indicated that MSC-CM infusion has therapeutic effects in T2DM rats and may be a promising novel therapeutic target.


Assuntos
Tecido Adiposo/citologia , Antioxidantes/farmacologia , Meios de Cultivo Condicionados/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Fígado/citologia , Células-Tronco Mesenquimais/metabolismo , Animais , Biomarcadores/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Inflamação/complicações , Inflamação/patologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Rim/efeitos dos fármacos , Rim/fisiopatologia , Lipídeos/sangue , Fígado/fisiopatologia , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Miocárdio/enzimologia , Miocárdio/patologia , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/patologia , Ratos Sprague-Dawley
18.
Acta Biomater ; 123: 222-229, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33476828

RESUMO

For decades, researchers have investigated the ideal material for clinical use in the cardiovascular field. Several substitute materials are used clinically, but each has drawbacks. Recently we developed biodegradable and elastic poly(ε-caprolactone-co-D,L-lactide) (P(CL-DLLA)) copolymers by adjusting the CL/DLLA composition, and evaluated the long-term efficacy and outcomes of these copolymers when used for right ventricular outflow tract (RVOT) replacement. This P(CL-DLLA) material was processed into a circular patch and used to replace a surgical defect in the RVOT of adult rats. Control rats were implanted with expanded polytetrafluoroethylene (ePTFE). Histologic evaluation was performed at 8, 24, and 48 weeks post-surgery. All animals survived the surgery with no aneurysm formation or thrombus. In all periods, ePTFE demonstrated fibrous tissue. In contrast, at 8 weeks P(CL-DLLA) showed infiltration of macrophages and fibroblast-like cells into the remaining material. At 24 weeks, P(CL-DLLA) was absorbed completely, and muscle-like tissue was present with positive staining for α-sarcomeric actinin and cardiac troponin T (cTnT). At 48 weeks, the cTnT-positive area had increased. The biodegradable and elastic P(CL-DLLA) induced cardiac regeneration throughout the 48-week study period. Future application of this material as a cardiovascular scaffold seems promising. STATEMENT OF SIGNIFICANCE: Biomaterials for reconstruction of tissue deficiencies in cardiovascular surgery require having suitable mechanical properties for cardiac tissue and biodegradation resulting in native tissue growth. Several biodegradable polymers such as poly-ε-caprolactone (PCL) and polylactic acid (PLA) have excellent biocompatibility and already been widely used clinically. In general, PCL and PLA are quite mechanically rigid. Meanwhile, significant elasticity is required in the high-pressure environment of the heart while the material is being replaced by new tissue. The present study provides a novel four-armed crosslinked poly(ε-caprolactone-co-D,L-lactide) (i.e., P(CL-DLLA)) material for cardiac patch, which was demonstrated properties including tissue-compatible, super-elastic nature, that made it suitable for long-term, in vivo RVOT repair. This super-elastic biomaterial could be useful for reconstruction of various muscular tissues deficiencies.


Assuntos
Caproatos , Poliésteres , Animais , Materiais Biocompatíveis/farmacologia , Dioxanos , Elasticidade , Lactonas , Polímeros , Ratos
19.
Med Phys ; 47(12): 6103-6112, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33012062

RESUMO

PURPOSE: We developed a thermoset shape memory bolus (shape memory bolus) made from poly-ε-caprolactone (PCL) polymer. This study aimed to investigate whether the shape memory bolus can be applied to radiotherapy as a bolus that conformally adheres to the body surface, can be created in a short time, and can be reused. METHODS: The shape memory bolus was developed by cross-linking tetrabranch PCL with reactive acrylate end groups. Dice similarity coefficient (DSC) was used to evaluate shape memory characterization before deformation and after restoration. In addition, the degree of adhesion to the body surface and crystallization time were calculated. Moreover, dosimetric characterization was evaluated using the water equivalent phantom and an Alderson RANDO phantom. RESULTS: The DSC value between before deformation and after restoration was close to 1. The degree of adhesion of the shape memory bolus (1.9%) was improved compared with the conventional bolus (45.6%) and was equivalent to three-dimensional (3D) printer boluses (1.3%-3.5%). The crystallization time was approximately 1.5 min, which was clinically acceptable. The dose calculation accuracy, dose distribution, and dose index were the equivalent compared with 3D boluses. CONCLUSION: The shape memory bolus has excellent adhesion to the body surface, can be created in a short time, and can be reused. In addition, the shape memory bolus needs can be made from low-cost materials and no quality control systems are required for individual clinical departments, and it is useful as a bolus for radiotherapy.


Assuntos
Impressão Tridimensional , Radiometria , Imagens de Fantasmas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
20.
Oxid Med Cell Longev ; 2020: 1362104, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32566073

RESUMO

Cancer, as a group, represents the most important cause of death worldwide. Unfortunately, the available therapeutic approaches of cancer including surgery, chemotherapy, radiotherapy, and immunotherapy are unsatisfactory and represent a great challenge as many patients have cancer recurrence and severe side effects. Methotrexate (MTX) is a well-established (antineoplastic or cytotoxic) chemotherapy and immunosuppressant drug used to treat different types of cancer, but its usage requires high doses causing severe side effects. Therefore, we need a novel drug with high antitumor efficacy in addition to safety. The aim of this study was the evaluation of the antitumor efficacy of zinc oxide nanoparticle (ZnO-NPs) and sorafenib alone or in combination on solid Ehrlich carcinoma (SEC) in mice. Sixty adult female Swiss-albino mice were divided equally into 6 groups as follows: control, SEC, MTX, ZnO-NPs, sorafenib, and ZnO-NPs+sorafenib; all treatments continued for 4 weeks. ZnO-NPs were characterized by TEM, zeta potential, and SEM mapping. Data showed that ZnO-NPs synergized with sorafenib as a combination therapy to execute more effective and safer anticancer activity compared to monotherapy as showed by a significant reduction (P < 0.001) in tumor weight, tumor cell viability, and cancer tissue glutathione amount as well as by significant increase (P < 0.001) in tumor growth inhibition rate, DNA fragmentation, reactive oxygen species generation, the release of cytochrome c, and expression of the apoptotic gene caspase-3 in the tumor tissues with minimal changes in the liver, renal, and hematological parameters. Therefore, we suggest that ZnO-NPs might be a safe candidate in combination with sorafenib as a more potent anticancer. The safety of this combined treatment may allow its use in clinical trials.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Nanopartículas Metálicas/química , Sorafenibe/farmacologia , Óxido de Zinco/farmacologia , Animais , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/metabolismo , DNA/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Feminino , Nanopartículas Metálicas/ultraestrutura , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Carga Tumoral/efeitos dos fármacos
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