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1.
Acta Biomater ; 171: 378-391, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37683967

RESUMO

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) occurs in the capsule surrounding breast implants. Malignant transformation of T cells by bacteria-driven chronic inflammation may be underlying BIA-ALCL mechanism. Here, we covalently grafted 2-methacryloyloxyethyl phosphorylcholine (MPC)-based polymers on a silicone surface and examined its effects against BIA-ALCL pathogenesis. MPC grafting strongly inhibited the adhesion of bacteria and bacteria-causing inflammation. Additionally, cancer T cell proliferation and capsule-derived fibroblast-cancer cell communication were effectively inhibited by MPC grafting. We further demonstrated the effect of MPC against the immune responses causing BIA-ALCL around human silicone implants in micro-pigs. Finally, we generated a xenograft anaplastic T cell lymphoma mouse model around the silicone implants and demonstrated that MPC grafting could effectively inhibit the lymphoma progression. This study is the first to show that bacteria-driven induction and progression of BIA-ALCL can be effectively inhibited by surface modification of implants. STATEMENT OF SIGNIFICANCE: Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a major concern in the field of plastic and reconstructive surgery. In this study, we demonstrate strong inhibitory effect of zwitterionic polymer grafting on BIA-ALCL pathogenesis and progression, induced by bacterial infection and inflammation, both in vitro and in vivo. This study provides a molecular basis for the development of novel breast implants that can prevent various potential complications such as excessive capsular contracture, breast implant illness, and BIA-ALCL incidence, as well as for expanding the biomedical applications of zwitterionic polymers.


Assuntos
Implantes de Mama , Neoplasias da Mama , Linfoma Anaplásico de Células Grandes , Humanos , Animais , Camundongos , Suínos , Feminino , Implantes de Mama/efeitos adversos , Linfoma Anaplásico de Células Grandes/etiologia , Linfoma Anaplásico de Células Grandes/epidemiologia , Linfoma Anaplásico de Células Grandes/patologia , Bactérias , Inflamação , Silicones
2.
Arch Pharm Res ; 46(1): 18-34, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36593377

RESUMO

Biological cell membranes are a natural barrier for living cells. In the last few decades, the cell membrane has been the main hurdle in the efficient delivery of bioactive and therapeutic agents. To increase the drug efficacy of these agents, additional mediators have been considered. Cell-penetrating peptides (CPPs), a series of oligopeptides composed of mostly hydrophobic and/or positively charged side chains, can increase the interaction with the cell membrane. CPP-based delivery platforms have shown great potential for the efficient and direct cytosol delivery of various cargos, including genes, proteins, and small molecule drugs. Bypassing endocytosis allows the CPP-based delivery systems greater defense against the degradation of protein-based drugs than other drug delivery systems. However, the delivery of CPPs exhibits intrinsically non-specific targeting, which limits their medical applications. To endow CPPs with specific targeting ability, the conjugation of pH-sensitive, enzyme-specific cleavable, and multiple targeting ligands has been reported. Optimization of the length and sequence of CPPs is still needed for various drugs of different sizes and surface charges. Toxicity issues in CPP-based delivery systems should be addressed carefully before clinical use.


Assuntos
Peptídeos Penetradores de Células , Peptídeos Penetradores de Células/química , Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Endocitose , Membrana Celular
3.
Biomater Res ; 26(1): 90, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36578054

RESUMO

BACKGROUND: The restoration of the functional ability of mesenchymal stem cells (MSCs) using epigenetic modification is very promising for patients with weak osteogenesis ability. This study focused on the acceleration of osteogenesis from MSCs using microRNA (miRNA)2861 and a cell-penetrating peptide (CPP), LK. METHODS: We performed MSCs penetration test of complex between the LK peptides and miRNA 2861. Three different experiments were performed to investigate the effects of miRNA 2861 on osteogenic differentiation in MSCs: 1) intensity of alizarin red staining, which reflects the status of mineralization by osteoblasts; 2) gene expression related to osteoblast differentiation; and 3) confirmation of corresponding protein translation for comparison with RNA expression levels. RESULTS: We found that cLK effectively delivered miRNA 2861 into the cytoplasm of human MSCs and accelerated osteogenic differentiation from MSCs, as well as mineralization. CONCLUSION: The complex of miRNA 2861 with LK may have a positive effect on the osteogenic differentiation from MSCs and mineralization. Therapies using miRNAs combined with LK may be good candidates for the augmentation of osteogenesis in patients.

4.
Antibiotics (Basel) ; 11(10)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36289996

RESUMO

Antimicrobial peptides (AMPs) have received increasing attention as potential alternatives for future antibiotics because of the rise of multidrug-resistant (MDR) bacteria. AMPs are small cationic peptides with broad-spectrum antibiotic activities and different action mechanisms to those of traditional antibiotics. Despite the desirable advantages of developing peptide-based antimicrobial agents, the clinical applications of AMPs are still limited because of their enzymatic degradation, toxicity, and selectivity. In this review, structural modifications, such as amino acid substitution, stapling, cyclization of peptides, and hybrid AMPs with conventional antibiotics or other peptides, will be presented. Additionally, nanodelivery systems using metals or lipids to deliver AMPs will be discussed based on the structural properties and action mechanisms of AMPs.

5.
Biomater Sci ; 9(23): 7826-7831, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34812802

RESUMO

We have developed a cell penetrating peptide (CPP) system with high selectivity and penetrability at nanomolar concentrations with a combination of an HER2-selective affibody, ZHER2:342 (ZHER2), and a dimeric α-helical leucine- and lysine-rich peptide, LK-2. ZHER2 and LK-2 are linearly fused together and expressed in a prokaryotic system to create the LK-2-ZHER2 protein, which can successfully distinguish and penetrate HER2-overexpressing cancer cells at nanomolar concentrations. LK-2-ZHER2 has the ability to intracellularly deliver doxorubicin as a conjugate form to enhance its anti-cancer effect on HER2-overexpressing breast cancer cells with a great selectivity. The selective penetrability was confirmed in vitro, in 3D spheroids, and in in vivo models. LK-2-ZHER2 has the capability to overcome the weak points of current CPPs, such as poor penetrability at low concentrations and a lack of selectivity, by combining powerful CPP and affibody sequences.


Assuntos
Neoplasias da Mama , Peptídeos Penetradores de Células , Proteínas Recombinantes de Fusão , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos
6.
7.
Nano Lett ; 21(1): 731-739, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33332127

RESUMO

Photothermal therapy (PTT) exploits nanomaterials with optimal heat conversion and cellular penetration using near-infrared (NIR) laser irradiation. However, current PTT agents suffer from inefficient heat conversion, poor intracellular delivery, and a high dose of probes along with excessive laser irradiation, causing limited therapeutic outcomes. Here, bumpy Au triangular nanoprisms (BATrisms) are developed for increasing the surface area, improving cell penetration, shifting the absorption peak to the NIR region, and enhancing the photothermal conversion efficiency (∼86%). Further, leucine (L)- and lysine (K)-rich cell-penetrating peptides (LK peptides) were employed to largely improve their cellular uptake efficiency. Importantly, a significant in vivo therapeutic efficacy with LK-BATrisms was demonstrated in a triple-negative breast cancer xenograft mice model. A very small dose of LK-BATrism (2.5 µg Au) was enough to exert antitumor efficacy under very low laser power (808 nm, 0.25 W/cm2), causing minimal tissue damages while very efficiently killing cancer cells.


Assuntos
Peptídeos Penetradores de Células , Hipertermia Induzida , Nanoestruturas , Animais , Linhagem Celular Tumoral , Ouro , Lasers , Camundongos , Fototerapia , Terapia Fototérmica
8.
J Control Release ; 330: 898-906, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33152392

RESUMO

We developed a pH-activatable cell-penetrating peptide dimer LH2 with histidine residues, which can penetrate cells, specifically in weak acidic conditions, even at few tens of nanomolar concentrations. LH2 effectively delivered paclitaxel into triple-negative breast cancer cells, MDA-MB-231, via formation of non-covalent complexes (PTX-LH2(M)) or covalent conjugates (PTX-LH2(C)). Moreover, LH2 showed prolonged circulation in the body and enhanced accumulation in tumors. Both PTX-LH2(M) and PTX-LH2(C) showed strong antitumor effects in a triple-negative breast cancer grafted mouse model at an extremely low dosage.


Assuntos
Antineoplásicos , Neoplasias da Mama , Peptídeos Penetradores de Células , Preparações Farmacêuticas , Neoplasias de Mama Triplo Negativas , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Peptídeos Penetradores de Células/uso terapêutico , Feminino , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Nus , Paclitaxel/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
9.
Eur J Pharm Sci ; 144: 105210, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31899341

RESUMO

The intracellular delivery of transcription factor/cofactor using cell penetrating peptide (CPP) can lead to selective osteogenesis. The present work investigates the cell-penetrating potential of the a cyclic, α-helical cell-penetrating peptide based on leucine and lysine residues (cLK) for intracellular delivery in MC3T3 cells and the osteogenic effects of a C-terminal proline­serine­threonine-rich (PST) domain of Runx2 using cLK in rat mesenchymal stem cells (MSCs). We confirmed that the combination of cLK and fluorescein 5-isothiocyanate (FITC)-fragmented-Runx2 (fRunx2) showed an enhanced cell-penetrating activity of FITC-fRunx2 compared with FITC-fRunx2 alone. In addition, the fRunx2-cLK group showed strong staining with alizarin red compared with other groups and the degree of alizarin red staining in the fRunx2-cLK group was also 1.2-fold higher than that in the fRunx2-Tat group. The ALP and osteocalcin gene expression levels in the fRunx2-cLK group were higher than those in the other groups. The fRunx2 transferred effectively into the cytoplasm aided by the cLK peptide and augmented the osteogenic differentiation of MSCs.


Assuntos
Peptídeos Penetradores de Células/farmacologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Osteogênese/efeitos dos fármacos , Peptídeos/química , Peptídeos/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Regulação da Expressão Gênica , Técnicas de Transferência de Genes , Glicoproteínas/metabolismo , Células-Tronco Mesenquimais , Camundongos , Ratos , Ratos Sprague-Dawley
10.
Chem Commun (Camb) ; 56(1): 74-77, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31790117

RESUMO

We developed a new method for the de novo formation of fluorophores based on citrate (DNFC) in biological samples. Use of an amide coupling reagent and microwave irradiation greatly facilitates the fluorophore formation on peptides and proteins with N-terminal cysteine or serine. Since N-terminal cysteine and serine can form thiazolopyridone- or oxazolopyridone-based fluorophores emitting blue and green fluorescence, respectively, by the DNFC staining, each organelle, cell and tissue exhibited a characteristic fluorescence distribution. The DNFC staining is able to provide a new potential protocol for future cell imaging, histology and diagnosis.


Assuntos
Corantes Fluorescentes/metabolismo , Sondas Moleculares/metabolismo , Peptídeos/metabolismo , Proteínas/metabolismo , Animais , Linhagem Celular Tumoral , Ácido Cítrico/metabolismo , Cisteína/química , Fluorescência , Corantes Fluorescentes/química , Células HEK293 , Humanos , Camundongos , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Sondas Moleculares/química , Células NIH 3T3 , Peptídeos/química , Estudo de Prova de Conceito , Proteínas/química , Piridonas/química , Piridonas/metabolismo , Serina/química , Tiazóis/química , Tiazóis/metabolismo
11.
Angew Chem Int Ed Engl ; 57(38): 12468-12472, 2018 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-30062753

RESUMO

Polymers having α,ß-unsaturated anhydrides as repeating units were synthesized by ring opening metathesis polymerization (ROMP). The anhydride moieties were ready-to-be-grafted with amines to form acid-labile cis-α,ß-unsaturated acid amide linkages. The pH-responsive reversible de-grafting can be controlled by changing the intramolecular accessibility between acid and amide groups. The alendronate-grafted ROMP polymers showed distinct pH-dependent cytotoxicity according to the anhydride structures.


Assuntos
Anidridos/química , Compostos Bicíclicos com Pontes/química , Polímeros/química , Alendronato/química , Amidas/química , Amidas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Polimerização , Polímeros/farmacologia
12.
Cancer Cell ; 28(3): 318-28, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26373279

RESUMO

Tumor recurrence following treatment is the major cause of mortality for glioblastoma multiforme (GBM) patients. Thus, insights on the evolutionary process at recurrence are critical for improved patient care. Here, we describe our genomic analyses of the initial and recurrent tumor specimens from each of 38 GBM patients. A substantial divergence in the landscape of driver alterations was associated with distant appearance of a recurrent tumor from the initial tumor, suggesting that the genomic profile of the initial tumor can mislead targeted therapies for the distally recurred tumor. In addition, in contrast to IDH1-mutated gliomas, IDH1-wild-type primary GBMs rarely developed hypermutation following temozolomide (TMZ) treatment, indicating low risk for TMZ-induced hypermutation for these tumors under the standard regimen.


Assuntos
Glioblastoma/genética , Recidiva Local de Neoplasia/genética , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioma/genética , Humanos , Isocitrato Desidrogenase/genética , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Temozolomida
13.
Cell Mol Neurobiol ; 35(7): 1049-59, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25990227

RESUMO

Alzheimer's disease (AD) is an age-related disorder that causes a loss of brain function. Hyperphosphorylation of tau and the subsequent formation of intracellular neurofibrillary tangles (NFTs) are implicated in the pathogenesis of AD. Hyperphosphorylated tau accumulates into insoluble paired helical filaments that aggregate into NFTs; therefore, regulation of tau phosphorylation represents an important treatment approach for AD. Heat shock protein 27 (Hsp27) plays a specific role in human neurodegenerative diseases; however, few studies have examined its therapeutic effect. In this study, we induced tau hyperphosphorylation using okadaic acid, which is a protein phosphatase inhibitor, and generated a fusion protein of Hsp27 and the protein transduction domain of the HIV Tat protein (Tat-Hsp27) to enhance the delivery of Hsp27. We treated Tat-Hsp27 to SH-SY5Y neuroblastoma cells for 2 h; the transduction level was proportional to the Tat-hsp27 concentration. Additionally, Tat-Hsp27 reduced the level of hyperphosphorylated tau and protected cells from apoptotic cell death caused by abnormal tau aggregates. These results reveal that Hsp27 represents a valuable protein therapeutic for AD.


Assuntos
Proteínas de Choque Térmico HSP27/administração & dosagem , Neuroblastoma/metabolismo , Ácido Okadáico/toxicidade , Proteínas Recombinantes de Fusão/administração & dosagem , Produtos do Gene tat do Vírus da Imunodeficiência Humana/administração & dosagem , Proteínas tau/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Proteínas de Choque Térmico , Humanos , Chaperonas Moleculares , Fármacos Neuroprotetores/administração & dosagem , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia
14.
Mol Med Rep ; 6(5): 1160-70, 2012 11.
Artigo em Inglês | MEDLINE | ID: mdl-22895564

RESUMO

The herb Liriope platyphylla (LP) has been considered to have curative properties for diabetes, asthma and neurodegenerative disorders. To examine the effects of steaming time and frequency of manufactured red LP (RLP) on the nerve growth factor (NGF) secretion ability and NGF receptor signaling pathway, the NGF concentration, cell differentiation, NGF signaling pathway and calcium concentration were analyzed in neuronal cells treated with several types of LPs manufactured under different conditions. The maximum NGF secretion was observed in B35 cells treated with 50 µg/ml LP extract steamed for 9 h (9-SLP) and with two repeated steps (3 h steaming and 24 h air-dried) carried out 7 times (7-SALP). No significant changes in viability were detected in any of the cells treated with the various LPs, with the exception of 0-SLP and 0-SALP. In addition, PC12 cell differentiation was induced by treatment with the NGF-containing conditional medium (CM) collected from the RLP-treated cells. The levels of TrkA and extracellular signal-regulated kinase (ERK) phosphorylation in the high affinity NGF receptor signaling pathway were significantly higher in the cells treated with 3-SLP or 1-SALP/3-SALP CM compared with those treated with the vehicle CM. In the low affinity NGF receptor pathway, the expression levels of most components were higher in the 9-, 15- and 24-SALP CM-treated cells compared with the vehicle CM-treated cells. However, this level was significantly altered in cells treated with 3-SALP CM. Furthermore, an examination of the RLP function on calcium regulation revealed that only the LP- or RLP-treated cells exhibited changes in intracellular and extracellular calcium levels. RLP induced a significant decrease in the intracellular calcium levels and an increase in the extracellular calcium levels. These results suggest the possibility that steaming-processed LP may aid in the relief of neurodegenerative diseases through the NGF secretion ability and NGF signaling pathway.


Assuntos
Cálcio/metabolismo , Liriope (Planta)/química , Fator de Crescimento Neural/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Células PC12 , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Ratos , Receptor trkA/metabolismo , Transdução de Sinais , Temperatura
15.
Bone ; 50(1): 149-55, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22036912

RESUMO

We investigated the therapeutic effect of topical Risedronate (RIS) on a mouse model of estrogen-deficient osteoporosis. Fourteen-week-old female mice were ovariectomized and assigned to 4 groups: SHAM-operated (SHAM), OVX mice treated with vehicle (OVX-V), OVX mice treated with 0.2% RIS (OVX-0.2% RIS), and OVX-mice treated with 0.02% RIS (OVX-0.02% RIS). Topical samples containing RIS were prepared in 10% (w/w) polyethylene glycol (PEG, MW 400) and 80 µg of sample was spread on the mice's mid-backs every 3 days for 5 weeks. Micro-CT analysis of femora demonstrated that OVX-0.2% RIS exhibited a 29% greater bone mineral density and 24% greater bone volume fraction than that of OVX-V group. Investigation of the trabecular bone in OVX-0.2% RIS revealed a 24% higher bone volume (BV/TV), 51% higher trabecular number (Tb.N), and 40% lower trabecular separation (Tb.Sp) compared to OVX-V mice. Additionally, bone phenotypes of tibiae were further confirmed by histological analysis. OVX-0.2% RIS group exhibited a 494% greater BV/TV, 464% less Tb.Sp, 81% greater active osteoclast surface (Oc.S/BS) and 26% less osteoclast number (N.Oc/BS) than that of OVX-V group. Collectively, these results indicated that topical delivery of RIS has powerful pharmaceutical effects on the prevention of osteoporosis and bone turnover.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/uso terapêutico , Ácido Etidrônico/análogos & derivados , Osteoporose/tratamento farmacológico , Administração Tópica , Animais , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/farmacologia , Ácido Etidrônico/administração & dosagem , Ácido Etidrônico/farmacologia , Ácido Etidrônico/uso terapêutico , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Ovariectomia , Ácido Risedrônico , Pele/citologia , Pele/efeitos dos fármacos , Tíbia/efeitos dos fármacos , Tíbia/ultraestrutura , Microtomografia por Raio-X
16.
Int J Pharm ; 419(1-2): 114-20, 2011 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-21807082

RESUMO

Ion-paired solutions of risedronate (RIS) with L-arginine (ARG), L-lysine (LYS), and diethylenetriamine (DETA) were tested in vitro for their potential to enhance the penetration of RIS across the skin of hairless mouse. The xylene solubilities of RIS paired with ARG, LYS, and DETA in molar ratios of 1:2, 1:2, and 1:1 were 8.9%, 12.0%, and 2.1%, respectively, in comparison with the solubility in deionized water, but non-ion-paired RIS was not detected in xylene. In vitro permeation tests were performed on the skin of hairless mice, and the results indicated that ion-paired RIS could penetrate mice skin about 36 times more effectively than RIS alone. The cumulative amount of ion paired RIS after 24 h resulted in 475.18±94.19 µg/cm(2) and 511.21±106.52 µg/cm(2) at molar ratio of 1:2 and 1:1. The cumulative amount of RIS alone was as low as 14.13±5.49 µg/cm(2) in 24h. The hairless mice showed no skin irritation after a single administration of RIS alone and ion-paired RIS (1:2 molar ratio with ARG, and 1:1 molar ratio with DETA). In this study, we found that RIS can be delivered transdermally, and the ion-paired system in an aqueous solution showed an enhanced flux through the skin barrier.


Assuntos
Conservadores da Densidade Óssea/farmacocinética , Ácido Etidrônico/análogos & derivados , Excipientes/química , Absorção Cutânea , Administração Cutânea , Animais , Arginina/química , Conservadores da Densidade Óssea/administração & dosagem , Ácido Etidrônico/administração & dosagem , Ácido Etidrônico/farmacocinética , Íons/química , Lisina/química , Camundongos , Camundongos Pelados , Permeabilidade , Poliaminas/química , Ácido Risedrônico , Solubilidade , Solventes/química , Água/química , Xilenos/química
17.
Lab Anim Res ; 27(1): 29-36, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21826157

RESUMO

Exercise training is highly correlated with the reduced glucose-stimulated insulin secretion (GSIS), although it enhanced insulin sensitivity, glucose uptake and glucose transporter expression to reduce severity of diabetic symptoms. This study investigated the impact of short-term swimming exercise on insulin regulation in the Goto-Kakizaki (GK) rat as a non-obese model of non-insulin-dependent diabetes mellitus. Wistar (W/S) and GK rats were trained 2 hours daily with the swimming exercise for 4 weeks, and then the changes in the metabolism of insulin and glucose were assessed. Body weight was markedly decreased in the exercised GK rats compare to their non-exercised counterpart, while W/S rats did not show any exercise-related changes. Glucose concentration was not changed by exercise, although impaired glucose tolerance was improved in GK rats 120 min after glucose injection. However, insulin concentration was decreased by swimming exercise as in the decrease of GSIS after running exercise. To identify the other cause for exercise-induced insulin down-regulation, the changes in the levels of key factors involved in insulin production (C-peptide) and clearance (insulin-degrading enzyme; IDE) were measured in W/S and GK rats. The C-peptide level was maintained while IDE expression increased markedly. Therefore, these results showed that insulin down-regulation induced by short-term swimming exercise likely attributes to enhanced insulin clearance via IDE over-expression than by altered insulin production.

18.
Lab Anim Res ; 27(2): 117-26, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21826171

RESUMO

In oriental medicine, Liriope platyphylla (LP) has long been regarded as a curative herb useful for the treatment of diabetes, asthma, and neurodegenerative disorders. The principal objective of this study was to assess the effects of steaming time and frequency for manufactured Red LP (RLP) on insulin secretion ability and insulin receptor signaling pathway. To achieve our goal, several types of LPs manufactured under different conditions were applied to INS cells and streptozotocin (STZ)-induced diabetic ICR mice, after which alterations in insulin concentrations were detected in the culture supernatants and sera. The optimal concentration for the investigation of insulin secretion ability was found to be 50 ug/mL of LP. At this concentration, maximum insulin secretion was observed in the INS cells treated with LP extract steamed for 3 h (3-SLP) with two repeated steps (3 h steaming and 24 h air-dried) carried out 9 times (9-SALP); no significant changes in viability were detected in any of the treated cells. Additionally, the expression and phosphorylation levels of most components in the insulin receptor signaling pathway were increased significantly in the majority of cells treated with steaming-processed LP as compared to the cells treated with LP prepared without steaming. With regard to glucose transporter (GLUT) expression, alterations of steaming time induced similar responses on the expression levels of GLUT-2 and GLUT-3. However, differences in steaming frequency were also shown to induce dose-dependent responses in the expression level of GLUT-2 only; no significant differences in GLUT-3 expression were detected under these conditions. Furthermore, these responses observed in vitro were similarly detected in STZ-induced diabetic mice. 24-SLP and 9-SALP treatment applied for 14 days induced the down-regulation of glucose concentration and upregulation of insulin concentration. Therefore, these results indicated that the steaming processed LP may contribute to the relief of diabetes symptoms and should be regarded as an excellent candidate for a diabetes treatment.

19.
Int J Mol Med ; 28(6): 961-71, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21822534

RESUMO

Pen-2 is a key regulator of the γ-secretase complex, which is involved in the production of the amyloid ß (Aß)-42 peptides, which ultimately lead to Alzheimer's disease (AD). While Pen-2 has been studied in vitro, Pen-2 function in vivo in the brains of transgenic (Tg) mice overexpressing human Pen-2 (hPen-2) protein has not been studied. This study aimed to determine whether Pen-2 overexpression could regulate the AD-like phenotypes in Tg mice. NSE/hPen-2 Tg mice were produced by the microinjection of the NSE/hPen-2 gene into the pronucleus of fertilized eggs. The expression of the hPen-2 gene under the control of the NSE promoter was successfully detected only in the brain and kidney tissue of NSE/hPen-2 Tg mice. Also, 12-month-old NSE/hPen-2 Tg mice displayed behavioral dysfunction in the water maze test, motor activity and feeding behavior dysfunction in food intake/water intake/motor activity monitoring system. In addition, tissue samples displayed dense staining with antibody to the Aß-42 peptide. Furthermore, NSE/hPen-2 Tg mice exhibiting feeding behavior dysfunction were significantly more apt to display symptoms related to diabetes and obesity. These results suggest that Pen-2 overexpression in NSE/hPen-2 Tg mice may induce all the AD-like phenotypes, including behavioral deficits, motor activity and feeding behavior dysfunction, Aß-42 peptide deposition and chronic disease induction.


Assuntos
Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/biossíntese , Encéfalo/metabolismo , Ativação Enzimática/genética , Expressão Gênica , Proteínas de Membrana/metabolismo , Fragmentos de Peptídeos/biossíntese , Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Secretases da Proteína Precursora do Amiloide/genética , Peptídeos beta-Amiloides/genética , Animais , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Comportamento Alimentar , Feminino , Humanos , Masculino , Aprendizagem em Labirinto/fisiologia , Proteínas de Membrana/genética , Memória , Camundongos , Camundongos Transgênicos , Atividade Motora/genética , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Fragmentos de Peptídeos/genética , Plasmídeos/genética , Transfecção , Células Tumorais Cultivadas
20.
Int J Mol Med ; 28(2): 223-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21491079

RESUMO

Synaptophysin is a synaptic vesicle glycoprotein involved in the regulation process for neurotransmitter release, which is distributed throughout neuroendocrine cells and all neurons in the brain and spinal cord. In an effort to determine whether amyloid ß (Aß)-42 peptides could influence the quantity and biochemical properties of synaptophysin, alterations in the levels of the synaptophysin protein in various soluble fractions were detected in the brains of four genotypes of transgenic mice (Tg) including Non-Tg, neuron-specific enolase (NSE)-hPS2m, NSE-hAPPsw and hAPPsw/hPS2m double Tg mice. Among the four genotypes of Tg mice, the highest levels of Aß-42 peptides were noted in hAPPsw/hPS2m, followed by NSE-hAPPsw, NSE-hPS2m and Non-Tg mice. In the brains of these mice displaying different levels of Aß-42 peptides, the levels of soluble synaptophysin were reduced significantly only in the hAPPsw/hPS2m double Tg mice compared to the Non-Tg mice. However, immunohistochemical analysis revealed no differences in the levels of total synaptophysin protein between the neocortex and hippocampus of the four different genotypes of mice. Western blot analysis using four-step fractions with differing solubility revealed a marked decrease in synaptophysin levels in the Tris-buffer saline fraction of hAPPsw/hPS2m double Tg mice and a significant increase in the formic acid fraction, relative to the Non-Tg mice. The results obtained from our in vivo experiments in mice are identical to the results observed in SK-N-MC cells treated with 100 nM Aß-42 peptides. Therefore, our experiments collectively suggest that Aß-42 peptides may alter the solubility without changing the total amount of synaptophysin.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Encéfalo/metabolismo , Presenilina-1/genética , Sinaptofisina/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/patologia , Células Cultivadas , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Presenilina-1/metabolismo , Solubilidade
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