Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Einstein (Sao Paulo) ; 18: eAO4876, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31576909

RESUMO

OBJECTIVE: To investigate the effects of sericin extracted from silkworm Bombyx mori cocoon on morphophysiological parameters in mice with obesity induced by high-fat diet. METHODS: Male C57Bl6 mice aged 9 weeks were allocated to one of two groups - Control and Obese, and fed a standard or high-fat diet for 10 weeks, respectively. Mice were then further subdivided into four groups with seven mice each, as follows: Control, Control-Sericin, Obese, and Obese-Sericin. The standard or high fat diet was given for 4 more weeks; sericin (1,000mg/kg body weight) was given orally to mice in the Control-Sericin and Obese-Sericin Groups during this period. Weight gain, food intake, fecal weight, fecal lipid content, gut motility and glucose tolerance were monitored. At the end of experimental period, plasma was collected for biochemical analysis. Samples of white adipose tissue, liver and jejunum were collected and processed for light microscopy analysis; liver fragments were used for lipid content determination. RESULTS: Obese mice experienced significantly greater weight gain and fat accumulation and had higher total cholesterol and glucose levels compared to controls. Retroperitoneal and periepididymal adipocyte hypertrophy, development of hepatic steatosis, increased cholesterol and triglyceride levels and morphometric changes in the jejunal wall were observed. CONCLUSION: Physiological changes induced by obesity were not fully reverted by sericin; however, sericin treatment restored jejunal morphometry and increased lipid excretion in feces in obese mice, suggesting potential anti-obesity effects.


Assuntos
Fármacos Antiobesidade/uso terapêutico , Dieta Hiperlipídica , Obesidade/tratamento farmacológico , Sericinas/uso terapêutico , Tecido Adiposo/patologia , Animais , Fármacos Antiobesidade/farmacologia , Peso Corporal/efeitos dos fármacos , Colesterol/análise , Dieta Hiperlipídica/efeitos adversos , Ingestão de Alimentos/efeitos dos fármacos , Fígado Gorduroso/patologia , Trânsito Gastrointestinal/efeitos dos fármacos , Teste de Tolerância a Glucose , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/etiologia , Obesidade/fisiopatologia , Reprodutibilidade dos Testes , Sericinas/farmacologia , Fatores de Tempo , Resultado do Tratamento , Triglicerídeos/análise , Ganho de Peso/efeitos dos fármacos
2.
BMC Complement Altern Med ; 19(1): 168, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291937

RESUMO

BACKGROUND: Several immunological pathways, particularly skin inflammation via various pro-inflammatory cytokines have been reported to be involved in the pathogenesis and clinical manifestations of psoriasis. The aim of the study was to investigate the potential role of naringin from Citrus maxima (Burm.) Merr and sericin from Bombyx mori combination in the treatment of psoriasis. Inhibitory effects on the expression of mRNA and the production of pro-inflammatory cytokines (TNF-α, IL-6, IL-23, and IL-12p40) were investigated. METHODS: Human peripheral blood mononuclear cells (hPBMCs) were isolated from 10 healthy subjects and 10 patients with psoriasis. The hPBMCs from each group were exposed to naringin or sericin alone, and the combination of naringin and sericin. The expression levels of mRNA and the production of all cytokines were determined using quantitative RT-PCR and ELISA, respectively. RESULTS: Naringin/sericin combination significantly decreased the expression of mRNA and the production of all pro-inflammatory cytokines in hPBMCs from patients with psoriasis. The potency of inhibitory activity was markedly higher than naringin or sericin alone. CONCLUSION: The activity of naringin/sericin combination on down-regulation of these pro-inflammatory cytokines suggested its potential clinical use in psoriasis as well as other inflammation-associated diseases. The combination might be used as a complementary therapy with conventional treatment in psoriasis to improve clinical efficacy and tolerability.


Assuntos
Citrus/química , Flavanonas/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Extratos Vegetais/farmacologia , Psoríase/tratamento farmacológico , Sericinas/farmacologia , Adulto , Anti-Inflamatórios/farmacologia , Citocinas/biossíntese , Citocinas/genética , Quimioterapia Combinada , Feminino , Flavanonas/uso terapêutico , Humanos , Técnicas In Vitro , Mediadores da Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/uso terapêutico , Sericinas/uso terapêutico , Adulto Jovem
3.
Neurol Res ; 41(4): 326-334, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30638158

RESUMO

OBJECTIVE: To verify the action of sericin associated to swim exercise with overload, on sciatic nerve repair in Wistar rats, after 22 days of nerve compression. METHODS: Forty animals been composed of five groups: control, injury, injury-sericin, injury-swimming and injury-sericin-swimming. During the lesion procedure, sericin, in hydrolyzed form, applied directly to the injury in the injury-sericin and injury-sericin-swimming groups. Injury-swimming and injury-sericin-swimming groups underwent to 5 days per week for 3 weeks, with a 10% overload of the animal's body weight, and a weekly progressive evolution of swimming time, lasting 15, 20 and 25 min/day. Pre and throughout the treatment period the animals performed evaluation of sciatic functional index and pressure pain threshold with digital von Frey filament. Euthanasia was performed on the 22nd postoperative day, and two fragments of the nerve were collected and prepared for descriptive and quantitative analysis. RESULTS: The sciatic functional index assessment showed significant differences in the motor function of the control until the 14th day. Regarding the allodynia, there was revealed a significant improvement in injury-swimming performance relative to injury, injury-sericin and injury-sericin-swimming, and the number of viable and non-viable nerve fibers smaller than 4 µm in diameter was significantly higher in the injury-sericin-swimming. CONCLUSION: swimming showed a better evolution of the nociceptive threshold and allodynia. Sericin treatment had exacerbated pro-inflammatory characteristics. On the other hand, the association of sericine and swimming showed a possible regulatory effect by resting swimming exercise, with a significant increase of fibers of smaller diameter.


Assuntos
Condicionamento Físico Animal/métodos , Neuropatia Ciática/tratamento farmacológico , Neuropatia Ciática/reabilitação , Sericinas/uso terapêutico , Natação , Animais , Modelos Animais de Doenças , Medição da Dor , Limiar da Dor/efeitos dos fármacos , Limiar da Dor/fisiologia , Ratos , Ratos Wistar , Nervo Isquiático/patologia , Neuropatia Ciática/fisiopatologia , Sericinas/metabolismo , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Resultado do Tratamento
4.
Arch Dermatol Res ; 310(10): 795-805, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30302557

RESUMO

Bacterial cellulose wound dressings containing silk sericin and PHMB (BCSP) were developed in our previous studies. It had good physical properties, efficacy, and safety. For further use as a medical material, this dressing was investigated for its efficacy and safety in split-thickness skin graft (STSG) donor-site wound treatment compared to Bactigras® (control). Moreover, the inflammatory responses to both dressings were also deeply investigated. For in vivo study, expressions of anti-inflammatory cytokines were intensely considered in the tissue interfacing area. The result showed that IL-4 and TGF-ß from BCSP-treated tissue had advantages over Bactigras®-treated tissue at 14 and 21 days post-implantation. For clinical study, a single-blinded, randomized controlled study was generated. The half of STSG donor site wound was randomly assigned to cover with BCSP or Bactigras®. Twenty-one patients with 32 STSG donor site wounds were enrolled. The results showed that wound-healing time was not significantly different in both dressings. However, wound quality of BCSP was better than Bactigras® at healing time and after 1 month (p < 0.05). The pain scores of BCSP-treated wound were statistically significant lower than Bactigras®-treated wound (p < 0.05). No sign of infection or adverse event was observed after treatment with both dressings. In conclusion, the inflammation responses of the dressing were clearly clarified. The advantages of BCSP were wound-quality improvement, pain reduction, and infection protection without adverse events. It was fit to be used as the alternative treatment of STSG donor site wound.


Assuntos
Bandagens/efeitos adversos , Biguanidas/uso terapêutico , Celulose/uso terapêutico , Desinfetantes/uso terapêutico , Polissacarídeos Bacterianos/uso terapêutico , Sericinas/uso terapêutico , Cicatrização/efeitos dos fármacos , Eritema/induzido quimicamente , Feminino , Humanos , Inflamação/induzido quimicamente , Interleucina-4/metabolismo , Masculino , Pessoa de Meia-Idade , Transplante de Pele/métodos , Fator de Crescimento Transformador beta1/metabolismo , Resultado do Tratamento
5.
Drug Res (Stuttg) ; 68(6): 317-327, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29132177

RESUMO

Silks are naturally occurring polymers that have been used clinically as sutures for hundreds of years. It's so for obtained from insects or worms, silk consists of a filament core protein, termed fibroin, and a glue-like coating made up of sericin proteins. An important component of silk has an extended history of being discarded as a waste in the course of silk processing. The cost of sericin for tissue engineering is underestimated and its capability in using as regenerative remedy has simply began to be explored. Its variable amino acid composition and various functional groups confer upon it attractive bioactive proteins, which are particularly interesting for biomedical programs. Because of its antioxidant properties, moisturizing ability, and mitogenic effect on mammalian cells, sericin is beneficial in cell regeneration and tissue engineering. Research shows that keratinocytes and fibroblasts have brought about the improvement of sericin-primarily based biomaterials for skin tissue repair, in particular as wound dressings. Moreover, sericin may be used for bone tissue engineering due to its ability to set off nucleation of bone-like hydroxyapatite. Stable silk sericin biomaterials, as films, sponges, and hydrogels, are obtained by means of cross-linking, ethanol precipitation, or mixing with different polymers. Now a day, sericin may also be used for delivery of drugs due to its chemical reactivity and pH-responsiveness which facilitate the fabrication of nano and microparticles, hydrogels, and conjugated molecules, enhancing the bioactivity of drugs. In this review, we outlined the current headways from extraction of sericin till its physical properties and biomedical applications.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Sericinas/uso terapêutico , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Humanos , Sericinas/química , Sericinas/isolamento & purificação , Sericinas/farmacologia
6.
Free Radic Biol Med ; 108: 803-818, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28476503

RESUMO

Sericin, a principal constituent of silk, is widely used in various biomedical applications. In addition, conferring protection against free radicals and oxidative damage add more value to its therapeutic potential. However, the antioxidant (AO) properties of silk sericin (SS) remains contingent on extraction procedures. In the present study, we have evaluated the effect of different extraction methods (conventional, autoclaving, urea, alkali and acid-degradation) on AO properties of SS from three Indian silk varieties [Antheraea assamensis (AA), Philosamia ricini (PR) and Bombyx mori (BM)]. The physico-chemical characterization studies revealed that the molecular weight of SS isolates of each method ranged from 10 to 220kDa along with varied protein structural biochemistry. SS extracts using urea-degradation (BM, PR and AA), conventional method and alkali-degradation (BM) displayed high percentage of ß-sheets, random coils and turns. Acid-degraded SS (PR, followed by AA and BM) showed the highest total flavonoid content while conventional method (PR), autoclaving (AA) and alkali-degradation (BM) displayed lowest flavonoid levels. Interestingly, SS extracted by autoclaving (BM and AA), acid-degradation (PR), conventional and alkali-degradation (BM, AA and PR) methods exhibited 50% reduction of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical. Moreover, the efficacy of antioxidant potential of SS extracted by different methods was found to be in the order of "alkali>autoclaving>conventional" as demonstrated in L929 cells. Correspondingly, the anti-lipid peroxidation activity of SS extracted by alkali method (AA, BM and PR) further confirmed better AO properties amid others. Thus, the present study demonstrates that the extraction methods may significantly affect AO activity of SS which might be of importance for potential cosmetic applications.


Assuntos
Antioxidantes/metabolismo , Bombyx/metabolismo , Fracionamento Químico/métodos , Sericinas/metabolismo , Seda/metabolismo , Animais , Antioxidantes/química , Antioxidantes/uso terapêutico , Pesquisa Biomédica , Flavonoides/química , Flavonoides/uso terapêutico , Peroxidação de Lipídeos , Morus , Estresse Oxidativo , Capacidade de Absorbância de Radicais de Oxigênio , Sericinas/química , Sericinas/uso terapêutico , Seda/química
7.
Drug Deliv Transl Res ; 7(1): 77-88, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27565984

RESUMO

Microbial contamination in wounds leading to severe sepsis can be treated by silver-based antiseptics. However, frequent application of silver-based antiseptics, staining of skin, burning, and irritation at application site resulted to poor patient compliances. Thus, we formulated sericin- and chitosan-capped silver nanoparticle (S/C-SNP)-loaded hydrogel for accelerated wound healing and antimicrobial properties. The wound healing property of sericin, antibacterial nature of chitosan and silver, and mucoadhesive property of carbopol were utilized in development of novel wound dressing hydrogel to investigate the combined effect of these materials for effective treatment of wounds. The chemical reduction method was successfully employed for the synthesis of SNPs using sericin and chitosan as a capping/reducing agent. The SNPs were characterized by ultraviolet-spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and transmission electron microscopy (TEM). The optimized SNPs were further used for preparation of carbopol hydrogel (0.5, 0.75, and 1.0 % w/v). The prepared hydrogels were characterized for pH, viscosity, and texture analysis. The antimicrobial activity and wound healing activity of the optimized hydrogel (S/C-SNPs G-1) demonstrated higher bactericidal activity and wound closure, as supported by results of histopathology. Hydrogel containing capped SNPs has application in wound healing treatment.


Assuntos
Antibacterianos/administração & dosagem , Quitosana/administração & dosagem , Hidrogéis/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Sericinas/administração & dosagem , Prata/administração & dosagem , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/uso terapêutico , Quitosana/química , Quitosana/uso terapêutico , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Feminino , Hidrogéis/química , Hidrogéis/uso terapêutico , Concentração de Íons de Hidrogênio , Masculino , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Ratos Wistar , Sericinas/química , Sericinas/uso terapêutico , Prata/química , Prata/uso terapêutico , Pele/efeitos dos fármacos , Pele/patologia , Testes de Irritação da Pele , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Viscosidade
8.
Exp Biol Med (Maywood) ; 242(4): 411-421, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27903836

RESUMO

Sericin has been implicated in lower cholesterolemic effect due to its properties with several mechanisms. Mitochondria are one of the most important targets to be affected in high blood cholesterol and glucose conditions. The protective role of sericin on mitochondria remains doubtful. To examine this role, electron microscopic, histopathologic, immunohistochemical, and biochemical studies were performed in a high-cholesterol diet/streptozotocin rat model. The results demonstrated that sericin reduced blood cholesterol without hypoglycemic effect. Sericin alleviated dysmorphic mitochondria in heart and liver but not in kidney and also decreased peculiar endoplasmic reticulum in the exocrine pancreas. In addition, sericin decreased hepatic steatosis and preserved zymogen granule referable to the decline of reactive oxygen species production in hepatic mitochondrial extraction and down-regulation of malondialdehyde expression in the liver and exocrine pancreas however irrelevant to lipase activity. This study suggests that sericin has antioxidative property to reduce blood cholesterol by means of diminishing fat deposit in hepatocyte and improves mitochondria and endoplasmic reticulum integrities. [Box: see text].


Assuntos
Antioxidantes/uso terapêutico , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Fígado Gorduroso/tratamento farmacológico , Hipercolesterolemia/tratamento farmacológico , Mitocôndrias/metabolismo , Sericinas/uso terapêutico , Animais , Bombyx , Colesterol/sangue , Dieta Hiperlipídica , Retículo Endoplasmático/metabolismo , Feminino , Rim/metabolismo , Rim/ultraestrutura , Fígado/metabolismo , Fígado/ultraestrutura , Malondialdeído/metabolismo , Miocárdio/metabolismo , Miocárdio/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/ultraestrutura , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Estreptozocina/toxicidade
9.
Microsc Res Tech ; 80(3): 321-330, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27859881

RESUMO

The study of calcium phosphate (CaP) nanoparticles in vivo is still incomplete, which has limited their applications for biomedical delivery. Herein, we synthesized amorphous spherical calcium phosphate (S-CaP) nanoparticles with an average size of 80 nm via a co-precipitation method in the presence of silk sericin as the regulation template. S-CaP was labeled by the near-infrared dye reagent DiR, and then, the labeled nanoparticles (S-CaP@DiR) were used to investigate the distribution and degradation in healthy mice by IVIS and TEM. The results showed that the S-CaP nanoparticles were mainly distributed in the liver, and ∼90% of them (500 µg) could be degraded by the liver within 2 weeks. Tumor-bearing mice were then prepared, and the S-CaP was injected intravenously. Strikingly, the nanoparticles can effectively target solid tumors in cancer cell-bearing mice, indicating that the solid tumor was a foundation for the enrichment of the nanoparticles by the EPR effect, which showed the important potential of biodegradable inorganic nanoparticles in clinical drugs for tumor therapy.


Assuntos
Fosfatos de Cálcio/uso terapêutico , Nanopartículas/química , Neoplasias/tratamento farmacológico , Sericinas/química , Animais , Fosfatos de Cálcio/administração & dosagem , Fosfatos de Cálcio/síntese química , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Camundongos , Camundongos Endogâmicos ICR , Microesferas , Nanopartículas/administração & dosagem , Nanopartículas/metabolismo , Nanopartículas/uso terapêutico , Tamanho da Partícula , Sericinas/administração & dosagem , Sericinas/uso terapêutico , Transfecção
10.
J Nat Med ; 71(1): 208-215, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27771849

RESUMO

The beneficial effect of cholesterol-lowering proteins and/or peptides derived from various dietary sources is continuously reported. A non-dietary protein from silk cocoon, sericin, has also demonstrated cholesterol-lowering activity. A sericin hydrolysate prepared by enzymatic hydrolysis was also expected to posses this effect. The present study was aimed at investigating the cholesterol-lowering effect of sericin peptides, so called "sericin-derived oligopeptides" (SDO) both in vivo and in vitro. The results showed that SDO at all three doses tested (10 mg kg-1 day-1, 50 mg kg-1 day-1, and 200 mg kg-1 day-1) suppressed serum total and non-HDL cholesterol levels in rats fed a high-cholesterol diet. Triglyceride and HDL-cholesterol levels were not significantly changed among all groups. The fecal contents of bile acids and cholesterol did not differ among high-cholesterol fed rats. SDO dose-dependently reduced cholesterol solubility in lipid micelles, and inhibited cholesterol uptake in monolayer Caco-2 cells. SDO also effectively bound to all three types of bile salts including taurocholate, deoxytaurocholate, and glycodeoxycholate. Direct interaction with bile acids of SDO may disrupt micellar cholesterol solubility, and subsequently reduce the absorption of dietary cholesterol in intestines. Taking all data together, SDO or sericin peptides exhibit a beneficial effect on blood cholesterol levels and could be potentially used as a health-promoting dietary supplement or nutraceutical product.


Assuntos
Colesterol/sangue , Hipercolesterolemia/tratamento farmacológico , Sericinas/uso terapêutico , Triglicerídeos/metabolismo , Animais , Células CACO-2 , Modelos Animais de Doenças , Humanos , Masculino , Oligopeptídeos , Ratos , Ratos Sprague-Dawley , Ratos Wistar
11.
Biotechnol Adv ; 33(8): 1855-67, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26523781

RESUMO

Sericin is an inexpensive glycoprotein obtained as a by-product in the silk industry. Its variable amino acid composition and diverse functional groups confer upon it attractive bioactive properties, which are particularly interesting for biomedical applications. Because of its antioxidant character, moisturizing ability, and mitogenic effect on mammalian cells, sericin is useful in cell culture and tissue engineering. Its positive effects on keratinocytes and fibroblasts have led to the development of sericin-based biomaterials for skin tissue repair, mainly as wound dressings. Additionally, sericin can be used for bone tissue engineering owing to its ability to induce nucleation of bone-like hydroxyapatite. Stable silk sericin biomaterials, such as films, sponges, and hydrogels, are prepared by cross-linking, ethanol precipitation, or blending with other polymers. Sericin may also be employed for drug delivery because its chemical reactivity and pH-responsiveness facilitate the fabrication of nano- and microparticles, hydrogels, and conjugated molecules, improving the bioactivity of drugs. Here, we summarized the recent advancements in the study of silk sericin for application in tissue engineering and drug delivery.


Assuntos
Antioxidantes/química , Bandagens , Sericinas/uso terapêutico , Engenharia Tecidual , Animais , Antioxidantes/uso terapêutico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Hidrogéis/química , Sericinas/biossíntese , Sericinas/química , Seda/química , Cicatrização
12.
Int J Mol Sci ; 15(8): 13624-36, 2014 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-25101847

RESUMO

This study aims to evaluate the effect of combined use of the racemic flavanone Naringenin (NRG) and the protein sericin as TNF-α blockers. Sericin (SMs) and (R/S) NRG-loaded Sericin (SNRGMs) microparticles were prepared by spray-drying, characterized in terms of morphology and particle size distribution, and encapsulation efficiency was determined. Concerning morphology and particle size distribution of microparticles, results indicated that they were not affected by the presence of NRG. The encapsulation efficiency was almost quantitative (93%), thus proving that sericin can be advantageously loaded with (R/S) NRG. Biological evaluation of (R/S) NRG, SMs and SNRGMs was then performed in lipopolysaccharide (LPS)-stimulated human peripheral blood mononuclear cells (hPBMC). SNRGMs resulted cytotoxic at the higher dose used (200 µg/mL) and the effect was greater than (R/S) NRG alone. Moreover, even if sericin alone was not effective in suppressing LPS-induced serum TNF-α levels, SNRGMs loaded with 9.3% of (R/S) NRG were significantly more potent than (R/S) NRG alone. In summary, this study provides the proof of concept that sericin-based microspheres loaded with TNF-α-blockers could contribute to the down regulation of the cytokine and represents the starting point for the development of new topical formulations for the treatment of middle-stage psoriasis.


Assuntos
Flavanonas/uso terapêutico , Microesferas , Psoríase/tratamento farmacológico , Sericinas/química , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Células Cultivadas , Química Farmacêutica , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Flavanonas/química , Flavanonas/farmacologia , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/toxicidade , Tamanho da Partícula , Sericinas/farmacologia , Sericinas/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo
13.
Biomed Res Int ; 2013: 904314, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24106722

RESUMO

The genipin-cross-linked silk sericin/poly(vinyl alcohol) (PVA) films were developed aiming to be applied as two-dimensional wound dressings for the treatment of superficial wounds. The effects of genipin cross-linking concentration on the physical and biological properties of the films were investigated. The genipin-cross-linked silk sericin/PVA films showed the increased surface density, tensile strength, and percentage of elongation, but decreased percentage of light transmission, water vapor transmission rate, and water swelling, compared to the non-cross-linked films. This explained that the cross-linking bonds between genipin and silk sericin would reduce the mobility of molecular chains within the films, resulting in the more rigid molecular structure. Silk sericin was released from the genipin-cross-linked films in a sustained manner. In addition, either L929 mouse fibroblast or HaCat keratinocyte cells showed high percentage of viability when cultured on the silk sericin/PVA films cross-linked with 0.075 and 0.1% w/v genipin. The in vivo safety test performed according to ISO 10993-6 confirmed that the genipin-cross-linked silk sericin/PVA films were safe for the medical usages. The efficacy of the films for the treatment of superficial skin wounds will be further investigated in vivo and clinically. The genipin-cross-linked silk sericin/PVA films would be promising choices of two-dimensional wound dressings for the treatment of superficial wounds.


Assuntos
Bandagens , Iridoides/uso terapêutico , Seda/uso terapêutico , Cicatrização , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Iridoides/química , Camundongos , Álcool de Polivinil/uso terapêutico , Sericinas/química , Sericinas/uso terapêutico , Seda/química
14.
Nutr Res ; 32(12): 956-64, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23244541

RESUMO

We have previously reported that dietary sericin improves epidermal dryness with the increased total Ceramide (Cer) in NC/Nga mice, an animal model of atopic dermatitis (AD). In this study, we hypothesized that the increased level of total Cer induced by dietary sericin would be related to the altered metabolism of glucosylceramide (GlcCer) and sphingomyelin (SM), major precursors of Cer generation. NC/Nga mice were fed a control diet (group CA: atopic control) or diets with 1% silk protein, either sericin (group S) or fibroin (group F) for 10 weeks. In the epidermis of group CA, total Cer (including Cer1, 2, 3/4 and 6) and all GlcCer species were reduced; these levels in group S were increased to levels similar to or higher than in the normal control group of BALB/c mice (group C). In addition, the protein expressions, but not mRNA expressions, of GlcCer synthase, ß-glucocerebrosidase, and acidic sphingomyelinase, enzymes for GlcCer synthesis, GlcCer and SM hydrolysis, respectively, were highly increased in group S. The epidermal levels of total Cer (including Cer2, 3/4, and 6) and all GlcCer species and of these enzyme proteins in group F were lower than in group S. Notably, alterations in total SM, SM1, SM3, and SM synthase 1, which were increased in group CA, were not significant between groups S and F. Cer5 and SM2 were not altered among groups. Dietary sericin enhanced the epidermal levels of all GlcCer and most Cer species with up-regulating protein expressions of GlcCer synthase, ß-glucocerebrosidase, and acidic sphingomyelinase.


Assuntos
Ceramidas/metabolismo , Proteínas na Dieta/farmacologia , Enzimas/metabolismo , Epiderme/efeitos dos fármacos , Glucosilceramidas/metabolismo , Sericinas/farmacologia , Esfingomielinas/metabolismo , Animais , Dermatite Atópica/tratamento farmacológico , Dieta , Proteínas na Dieta/uso terapêutico , Epiderme/enzimologia , Epiderme/metabolismo , Glucosilceramidase/metabolismo , Glucosiltransferases/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos , Sericinas/uso terapêutico , Esfingomielina Fosfodiesterase/metabolismo , Regulação para Cima
15.
Waste Manag Res ; 30(3): 217-24, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21558082

RESUMO

Silk is composed of two major proteins, fibroin (fibrous protein) and sericin (globular, gumming protein). Fibroin has been used in textile manufacturing and for several biomaterial applications, whereas sericin is considered a waste material in the textile industry. Sericin has recently been found to activate the proliferation of several cell-lines and has also shown various biological activities. Sericin can form a gel by itself; however, after mixing with other polymers and cross-linking it can form a film or a scaffold with good characteristics that can be used in the cosmetic and pharmaceutical industries. Sericin is proven to cause no immunological responses, which has resulted in a more acceptable material for biological applications.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Bombyx/química , Proteínas de Insetos/uso terapêutico , Sericinas/uso terapêutico , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Materiais Biocompatíveis/farmacologia , Bombyx/fisiologia , Fibroínas/química , Fibroínas/isolamento & purificação , Proteínas de Insetos/química , Proteínas de Insetos/farmacologia , Proteínas de Insetos/fisiologia , Sericinas/química , Sericinas/farmacologia , Sericinas/fisiologia , Indústria Têxtil , Resíduos
16.
J Hepatobiliary Pancreat Sci ; 19(4): 354-60, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21678022

RESUMO

BACKGROUND/PURPOSE: Cryopreservation is necessary for the long-term storage of islet cells and to increase the practicality of clinical islet transplantation. Fetal bovine serum (FBS) supplemented with 10% dimethyl sulfoxide (DMSO) is generally used as a freezing medium for islet cells. However, FBS should ideally be avoided in cell culture and transplantation because of recent animal health problems, such as bovine spongiform encephalopathy and viral infections. The aim of this study was to develop a new serum-free freezing medium by examining the effectiveness of the silk protein sericin, which is produced by Bombyx mori. METHODS: Islets prepared from Lewis rats by collagenase digestion and Histopaque gradient centrifugation, followed by culture in medium containing 0.1% sericin for 3 days, were cryopreserved using 0.1, 0.5, 1, 2, and 5% sericin or FBS. DMSO (1, 4, 7, 10, and 15%) was added to the medium as a cryoprotectant. After thawing, on days 1, 4, 7, and 14, viable islets were counted in order to evaluate their survival. Insulin secretion was measured in vitro by a static incubation test on day 4. The in vivo function of cultured islets was tested by syngeneic transplantation. Islets were evaluated histologically and immunohistochemically after transplantation. RESULTS: There were no significant differences between freezing medium containing 1% sericin and that containing 10% FBS with regard to the survival rate of islets and stimulated insulin secretion. Following transplantation, islets rapidly reversed hyperglycemia and maintained normal glycemic control. In addition, the use of 7% DMSO as a cryoprotectant with sericin showed the same results as higher DMSO concentrations with FBS. CONCLUSION: The present results showed that serum-free medium containing sericin is useful for both cryopreservation and cell culture.


Assuntos
Criopreservação/métodos , Ilhotas Pancreáticas , Preservação de Órgãos/métodos , Sericinas/uso terapêutico , Animais , Meios de Cultura Livres de Soro/química , Insulina/metabolismo , Secreção de Insulina , Masculino , Técnicas de Cultura de Órgãos , Ratos , Ratos Endogâmicos Lew
17.
Int J Pharm ; 414(1-2): 193-202, 2011 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-21619916

RESUMO

Aqueous preparations of silk protein (sericin) films were prepared to evaluate their biodegradation properties. In the absence of trypsin, sericin film swelled rapidly, kept its shape, and remained unaltered for 28 days or longer due to form ß-sheet structures. In the presence of trypsin, sericin film gradually degraded; since the rate depended on the concentration of trypsin, the films likely underwent enzymatic hydrolysis. Sericin film incorporating the model protein drug fluorescein isothiocyanate-albumin (FA) also gradually degraded in the presence of trypsin and resulted in the sustained release of FA for 2 weeks or longer; in contrast, FA release was quite slow in the absence of trypsin. It is expected that sericin film has potential as a biodegradable and drug-releasing carrier. To evaluate the practical applicability of sericin film for the repair of defective tissues, fibroblast growth factor-2 (FGF-2) was incorporated into sericin films and the films were implanted on skull defects in rats. Whereas FGF-2 release was suppressed in the absence of trypsin in vitro, it appears that FGF-2, immobilized by ionic interactions between sericin and FGF-2, can be sustained-released in vivo from films incorporating 2500 or 250 ng of FGF-2 to support the growth of tissue around wounds.


Assuntos
Produtos Biológicos/química , Sistemas de Liberação de Medicamentos , Fator 2 de Crescimento de Fibroblastos/química , Sericinas/química , Animais , Fatores Biológicos/análise , Fatores Biológicos/química , Fatores Biológicos/metabolismo , Fatores Biológicos/uso terapêutico , Produtos Biológicos/análise , Produtos Biológicos/metabolismo , Produtos Biológicos/uso terapêutico , Bombyx , Portadores de Fármacos , Composição de Medicamentos , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Fator 2 de Crescimento de Fibroblastos/análise , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/análise , Masculino , Ratos , Ratos Sprague-Dawley , Sericinas/análise , Sericinas/metabolismo , Sericinas/uso terapêutico , Fraturas Cranianas/terapia , Tripsina/metabolismo , Cicatrização/fisiologia
18.
Biol Pharm Bull ; 32(9): 1594-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19721238

RESUMO

The protein sericin is the main constituent of silk. We investigated the effects of sericin on corneal wound healing in Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model for human type 2 diabetes. Corneal wounds were prepared by removal of the corneal epithelium, and documented using a TRC-50X equipped with a digital camera. Sericin solutions were instilled into the eyes of rats five times a day following corneal abrasion. Plasma glucose and triglycerides were determined using an Accutrend GCT. Cholesterol and insulin were measured using a Cholesterol E-Test Kit and ELISA Insulin Kit, respectively. The plasma levels of glucose, triglycerides, cholesterol and insulin in 38-week-old OLETF rats were significantly higher than in Long-Evans Tokushima Otsuka (LETO) rats used as normal controls, and the rate of corneal wound healing in OLETF rats was slower than in LETO rats. The corneal wounds of rats instilled with saline showed almost complete healing by 72 h after corneal epithelial abrasion. On the other hand, the corneal healing rate of OLETF rats instilled with 10% sericin solution was significantly higher than that of LETO rats instilled with saline, and the wounds showed almost complete healing at 48 h after abrasion. The corneal healing rate increased with increasing sericin concentration. The present study demonstrates that the corneal wound healing rate in OLETF rat is slower than in LETO rats, and the instillation of sericin solution has a potent effect in promoting wound healing and wound-size reduction in LETO and OLETF rats.


Assuntos
Perfuração da Córnea/tratamento farmacológico , Perfuração da Córnea/fisiopatologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/fisiopatologia , Sericinas/metabolismo , Sericinas/uso terapêutico , Cicatrização/efeitos dos fármacos , Animais , Perfuração da Córnea/complicações , Diabetes Mellitus Tipo 2/complicações , Modelos Animais de Doenças , Humanos , Masculino , Ratos , Ratos Endogâmicos OLETF , Ratos Long-Evans , Sericinas/farmacologia , Cicatrização/fisiologia
19.
Biol Pharm Bull ; 32(5): 933-6, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19420767

RESUMO

The protein sericin is the main constituent of silk. We demonstrate the effects of sericin on corneal wound healing in rat debrided corneal epithelium. We also determined the effects of sericin on cell adhesion and proliferation in a human cornea epithelial cell line (HCE-T). Epithelium was removed from the corneas of rats with a BD Micro-Sharp, and wounded corneas were dyed with a 1% fluorescein solution. The corneal wounds were monitored using a fundus camera TRC-50X equipped with a digital camera. The corneal wound of rats instilled with saline was approximately 10% healing at 12 h, and approximately 65% healing at 24 h after corneal epithelial abrasion. The corneal wounds of rats instilled with saline showed almost complete healing by 36 h after corneal epithelial abrasion. On the other hand, the corneal healing rate of rats instilled with sericin solution was higher than that of rats instilled with saline, and the corneal healing rate constant increased with increasing sericin concentration. In addition, the adhesion and proliferation of HCE-T cells treated with 0.01-0.5% sericin solutions were enhanced, reaching a maximum at treatments with 0.2 and 0.1% sericin solutions, respectively. The present study demonstrates that the instillation of sericin solution has a potent effect in promoting wound healing and wound-size reduction in rats, probably caused by increasing cell movement and proliferation.


Assuntos
Epitélio Anterior/lesões , Ferimentos Oculares Penetrantes/tratamento farmacológico , Sericinas/uso terapêutico , Cicatrização/efeitos dos fármacos , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Desbridamento , Modelos Animais de Doenças , Epitélio Anterior/efeitos dos fármacos , Humanos , Instilação de Medicamentos , Masculino , Ratos , Ratos Wistar , Sericinas/administração & dosagem , Cloreto de Sódio/administração & dosagem , Fatores de Tempo , Resultado do Tratamento
20.
Alcohol Alcohol ; 43(3): 246-53, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18263900

RESUMO

AIMS: The purpose of this study was to investigate the protective effects of sericin protein (SP) on alcohol-induced hepatic injury in mice and the possible mechanisms. METHODS: SP (0.375, 0.75 and 1.50 g/kg body weight) was dissolved in distilled water and given to mice by gavage 1 hour before the alcohol (56% wt/vol, 14.2 ml/kg b.w.) treatment for 30 days, then blood, urine and liver were collected, processed and used for alcohol concentration mensuration, various biochemical estimations and histopathological examination. RESULTS: The concentration of alcohol evidently decreased in serum and increased in urine in SP treated mice as compared to alcohol-administered animals. Chronic alcohol administration resulted in significantly increase in the levels of transaminase (AST and ALT) and malondialdehyde (MDA) but decrease of glutathione (GSH), glutathione peroxidase (GSH-PX), catalase (CAT) and superoxide dismutase (SOD) in the serum and liver. Hepatic triglyceride (TG) also increased. When mice ingested high doses of SP (0.75 and 1.50 g/kg b.w.) the levels of antioxidant enzymes in the serum were restored to normal. However, hepatic CAT and GSH were still below normal, although a trend of significant increases was observed in comparison with alcohol treatment group. CONCLUSIONS: The results indicated that SP was able to hasten the alcohol elimination through urine directly and enhance the ethanol oxidation rate in liver. Simultaneously, SP may exert a protective effect against lipid peroxidation by scavenging reactive oxygen species and elevating the activity of antioxidant enzymes, in consequence prevented the peroxidative deterioration of structural lipids in membranous organelles, especially mitochondria and karyon.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/tratamento farmacológico , Hepatopatias Alcoólicas/prevenção & controle , Sericinas/uso terapêutico , Consumo de Bebidas Alcoólicas/patologia , Sequência de Aminoácidos , Animais , Bombyx , Hepatopatias Alcoólicas/etiologia , Hepatopatias Alcoólicas/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Dados de Sequência Molecular , Sericinas/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA