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1.
J Cancer ; 15(2): 309-316, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38169554

RESUMO

Cancer cells are characterized by apoptosis evasion and uncontrolled cell cycle progression. To combat these characteristics, efforts have been made to find novel natural-source anticancer compounds. The aim of this work is to find new anticancer compounds in Polyporus ulleungus (P. ulleungus) mycelial culture extracts. P. ulleungus mycelium was cultured on four individual media (DYB, MEB, MYB, and PDB) and four extracts were generated from the mycelium culture media. Extracts of P. ulleungus mycelium cultured in MEB medium (pu-MEB) significantly reduced cancer cell growth by triggering apoptosis and S phase arrest. Furthermore, the anticancer effects of pu-MEB were not confined to one type of cancer. Taken together, our results confirmed that P. ulleungus mycelia cultured in MEB medium produce metabolites that exhibit anticancer properties. Development of an optimal medium for P. ulleungus mycelium through optimization of medium components will enable P. ulleungus mycelium to produce metabolites with more anticancer efficacy.

2.
Mycobiology ; 51(4): 256-263, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37711981

RESUMO

Species in the genus Trametes (Basidiomycota, Polyporales) have been used in natural medicine for a long time. Many studies reported that mycelia or fruiting bodies of Trametes spp. exhibited effects of antioxidant, anti-inflammatory, anticancer, and antimicrobial activities. However, comparative analysis in this genus is scarce due to limitation of morphological identification and the sample number. In this study, the 19 strains of seven Trametes species were chosen to generate a five-gene-based phylogeny with the 31 global references. In addition, 39 culture extracts were prepared for 13 strains to test for anticancer and antibacterial activities. Strong anticancer activities were found in several extracts from T. hirsuta and T. suaveolens. Anticancer activities of T. suaveolens, T. cf. junipericola and T. trogii were first described here. The antibacterial ability of T. versicolor and T. hirsuta extracts has been confirmed. The antibacterial activities of T. suaveolens have been reported at the first time in this study. These results suggest an efficient application of the genus Trametes as the drug resources especially for anticancer agents.

3.
J Cancer ; 14(11): 2075-2084, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37497414

RESUMO

Most conventional anticancer drugs cause resistance to chemotherapy, which has emerged as one of the major obstacles to cancer treatment. In order to address this issue, efforts have been made to select new anticancer compounds from natural sources. The aim of this study is to identify novel anticancer compounds from mycelial culture extracts belonging to Polyporus tuberaster (P. tuberaster). Here, we found that mycelial culture extracts of P. tuberaster cultured in PDB medium (pt-PDB) effectively inhibited cancer cell growth. pt-PDB reduced the growth of cancer cells through apoptosis induction and S-phase arrest. The anticancer efficacy of pt-PDB was not to limited to one type of cancer. Furthermore, unlike traditional anticancer medications, pt-PDB did not increase the proportion of side population (SP) cells, which plays a key role in the development of chemoresistance. Taken together, we discovered a novel anticancer drug candidate that has anticancer properties without increasing the proportion of SP cells. This new drug candidate can be used for the treatment of cancer, especially chemoresistant malignancies, and will provide a breakthrough in the treatment of chemoresistant cancer.

4.
J Cancer ; 14(1): 50-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36605488

RESUMO

One of the biggest obstacles in cancer treatment is the development of chemoresistance. To overcome this, attempts have been made to screen novel anticancer substances derived from natural products. The purpose of this study is to find new anticancer candidates in the mycelium culture extract of mushrooms belonging to Polyporus. Here, we used a high-throughput screening to find agents capable of inhibiting cancer cell proliferation. The culture extract of Polyporus Parvovarius mycelium in DY medium (pp-DY) was effective. pp-DY inhibited cancer cell proliferation by inducing apoptosis and S-phase arrest. The anticancer property of pp-DY was not only effective against one type of cancer, but also against another type of cancer. Compound fractionation was performed, and the active ingredient exhibiting anticancer effects in pp-DY was identified as 3,4-dihydroxybenzaldehyde (Protocatechualdehyde, PCA). PCA, like pp-DY, inhibited the proliferation of cancer cells by inducing apoptosis and S-phase arrest. Furthermore, unlike conventional anticancer drugs, PCA did not increase the proportion of the side population that plays the most important role in the development of chemoresistance. Taken together, our data revealed the novel mycelium culture extract that exhibited anticancer property, and identified active ingredients that did not activate a proportion of the side population. These novel findings may have clinical applications in the treatment of cancer, particularly chemo-resistant cancer.

5.
Front Pharmacol ; 13: 999192, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36532751

RESUMO

Ginseng and ginsenosides have been reported to have various pharmacological effects, but their efficacies depend on intestinal absorption. Compound K (CK) is gaining prominence for its biological and pharmaceutical properties. In this study, CK-enriched fermented red ginseng extract (DDK-401) was prepared by enzymatic reactions. To examine its pharmacokinetics, a randomized, single-dose, two-sequence, crossover study was performed with eleven healthy Korean male and female volunteers. The volunteers were assigned to take a single oral dose of one of two extracts, DDK-401 or common red ginseng extract (DDK-204), during the initial period. After a 7-day washout, they received the other extract. The pharmacokinetics of DDK-401 showed that its maximum plasma concentration (Cmax) occurred at 184.8 ± 39.64 ng/mL, Tmax was at 2.4 h, and AUC0-12h was 920.3 ± 194.70 ng h/mL, which were all better than those of DDK-204. The maximum CK absorption in the female volunteers was higher than that in the male volunteers. The differentially expressed genes from the male and female groups were subjected to a KEGG pathway analysis, which showed results in the cell death pathway, such as apoptosis and necroptosis. In cytotoxicity tests, DDK-401 and DDK-204 were not particularly toxic to normal (HaCaT) cells, but at a concentration of 250 µg/mL, DDK-401 had a much higher toxicity to human lung cancer (A549) cells than DDK-204. DDK-401 also showed a stronger antioxidant capacity than DDK-204 in both the DPPH and potassium ferricyanide reducing power assays. DDK-401 reduced the reactive oxygen species production in HaCaT cells with induced oxidative stress and led to apoptosis in the A549 cells. In the mRNA sequence analysis, a signaling pathway with selected marker genes was assessed by RT-PCR. In the HaCaT cells, DDK-401 and DDK-204 did not regulate FOXO3, TLR4, MMP-9, or p38 expression; however, in the A549 cells, DDK-401 downregulated the expressions of MMP9 and TLR4 as well as upregulated the expressions of the p38 and caspase-8 genes compared to DDK-204. These results suggest that DDK-401 could act as a molecular switch for these two cellular processes in response to cell damage signaling and that it could be a potential candidate for further evaluations in health promotion studies.

6.
Holist Nurs Pract ; 36(4): 247-254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32282561

RESUMO

The study aimed to examine the effects of self-acupunctural hand massage using aromatic oil on the stress, fatigue, and vital signs of Korean middle-aged women. A quasi-experimental study using a pretest/posttest control group, nonsynchronized design was employed. The study participants consisted of 55 middle-aged women (27 in the experiment group and 28 in the control group), who visited a community center in Seoul, South Korea. Self-acupunctural hand massage using aromatic oil as an experimental intervention was performed once per day, 6 minutes per session for the left and right hands each, for 3 weeks. A questionnaire was designed to measure the general characteristics, stress, fatigue, and vital signs (blood pressure and pulse rate). There were significant differences in the degrees of stress, fatigue, and vital signs (blood pressure) between the 2 groups. Self-acupunctural hand massage using aromatic oil decreased the stress, fatigue, and vital signs (blood pressure) of Korean middle-aged women. Self-acupunctural hand massage using aromatic oil can be utilized as an effective nursing intervention for decreasing stress, fatigue, and vital signs (blood pressure) for middle-aged women in clinical practice.


Assuntos
Fadiga , Massagem , Pressão Sanguínea/fisiologia , Fadiga/terapia , Feminino , Frequência Cardíaca , Humanos , Pessoa de Meia-Idade , Sinais Vitais
7.
J Exerc Sci Fit ; 17(1): 26-33, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30662511

RESUMO

BACKGROUND/OBJECTIVE: South Korea's 2018 Report Card on Physical Activity for Children and Youth is the second comprehensive evaluation of physical activity and the sources of influence based on the 10 core indicators provided by the Active Healthy Kids Global Alliance. It will serve as an advocacy tool to promote physical activity among children and youth. METHODS: Three national surveillance data (i.e., 2017 Korea Youth Risk Behavior Web-based Survey, 2016 Korea National Health and Nutrition Examination Survey, 2016 Physical Activity Promotion System) were used as main sources to evaluate the indicators. Descriptive statistics were performed to obtain prevalence estimates of physical activity-related indicators. In addition, expert opinions as well as the most recently available published or unpublished relevant sources were synthesized. RESULTS: South Korea's 2018 Report Card, compared to the 2016 Report Card, showed favourable changes in the Active Transportation (B+), Organized Sports Participation (C), Sedentary Behaviours (D), and School (D+) indicators, while unfavourable changes were shown in Overall Physical Activity (F) and Government (D). Physical Fitness was graded as D+. In parallel with the 2016 Report Card, Active Play, Family and Peers, and Community and Environment remain ungraded due to insufficient data. CONCLUSIONS: Successes as well as gaps and research needs were identified in the 2018 Report Card. Though some indicators have shown improvement, most children and youth continue to be insufficiently physically active with overall poor grades (Average of D+). To achieve substantial improvement in all grades in future Report Cards, more institutional and governmental support and investment is needed to promote physical activity. Furthermore, effort should be made to generate data pertaining to the indicators that were ungraded.

8.
Plant Physiol ; 179(2): 558-568, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30545904

RESUMO

Root hairs are important for absorption of nutrients and water from the rhizosphere. The Root Hair Defective-Six Like (RSL) Class II family of transcription factors is expressed preferentially in root hairs and has a conserved role in root hair development in land plants. We functionally characterized the seven members of the RSL Class II subfamily in the rice (Oryza sativa) genome. In root hairs, six of these genes were preferentially expressed and four were strongly expressed. Phenotypic analysis of each mutant revealed that Os07g39940 plays a major role in root hair formation, based on observations of a short root hair phenotype in those mutants. Overexpression (OX) for each of four family members in rice resulted in an increase in the density and length of root hairs. These four members contain a transcription activation domain and are targeted to the nucleus. They interact with rice Root Hairless1 (OsRHL1), a key regulator of root hair development. When heterologously expressed in epidermal cells of Nicotiana benthamiana leaves, OsRHL1 was predominantly localized to the cytoplasm. When coexpressed with each of the four RSL Class II members, however, OsRLH1 was translocated to the nucleus. Transcriptome analysis using Os07g39940-OX plants revealed that 86 genes, including Class III peroxidases, were highly up-regulated. Furthermore, reactive oxygen species levels in the root hairs were increased in Os07g39940-OX plants but were drastically reduced in the os07g39940 and rhl1 mutants. Our results demonstrate that RSL Class II members function as essential regulators of root hair development in rice.


Assuntos
Núcleo Celular/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Núcleo Celular/genética , Citoplasma/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Mutação , Oryza/genética , Oryza/crescimento & desenvolvimento , Epiderme Vegetal/genética , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Transporte Proteico , Espécies Reativas de Oxigênio/metabolismo
9.
Cytokine ; 63(1): 27-35, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23669253

RESUMO

Vitamin D is an important factor for calcium and phosphorus homeostasis. A negative relationship has been observed between vitamin D status and diseases such as cancer, arthritis, diabetes, and muscle fiber atrophy. However, the relationship between vitamin D and prevention of skeletal muscle damage has not been clearly elucidated. The purpose of this study was to investigate the effects of vitamin D on exercise-induced muscle changes. Rats were divided into 3 groups: (1) sedentary control (C: n=10), (2) high-intensity exercise (HE: n=10), and (3) high-intensity exercise with vitamin D supplementation (HED: n=10; i.p. 1000 IU/kg body weight). Rats were trained for 30 min/day on treadmills (5 days/week for 8 weeks) with the running speed gradually increased up to 30 m/min at a 3° incline. At the end of the training period, the running speed was 38 m/min at a 5° incline. The high-intensity exercise significantly increased plasma creatine kinase (CK) and lactate dehydrogenase (LDH) activity. In addition, IL-6 and TNF-α levels as well as phosphorylation of AMPK, p38, ERK1/2, IKK, and IκB were significantly increased. Vitamin D-treated rats showed a significant decrease in plasma CK level, phosphorylation of AMPK, p38, ERK1/2, IKK, and IκB, and gene expression of IL-6 and TNF-α. Furthermore, the protein expression of vitamin D receptor (VDR) was highly increased in the muscles of HED-treated rats, respectively. Therefore, we concluded that vitamin D may play a pivotal role in exercise-induced muscle damage and inflammation through the modulation of MAPK and NF-κB involved with VDR.


Assuntos
Colecalciferol/uso terapêutico , Suplementos Nutricionais , Inflamação/tratamento farmacológico , Músculo Esquelético/patologia , Condicionamento Físico Animal/efeitos adversos , Animais , Biomarcadores/sangue , Colecalciferol/farmacologia , Creatina Quinase/sangue , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Ensaio de Imunoadsorção Enzimática , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/genética , Inflamação/patologia , Interleucina-6/sangue , Interleucina-6/genética , Interleucina-6/metabolismo , L-Lactato Desidrogenase/sangue , Sistema de Sinalização das MAP Quinases , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , NF-kappa B/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Calcitriol/metabolismo , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
10.
Discov Med ; 13(70): 229-34, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22463799

RESUMO

Rheumatoid arthritis (RA) is a chronic, systemic inflammatory arthritis that can lead to significant damage and dysfunction of involved joints. Prior to 1998, treatment options were limited to disease modifying anti-rheumatic drugs, commonly referred to as DMARDs like methotrexate, sulfasalazine, hydroxychloroquine, and gold salts. Tumor necrosis factor alpha (TNF-α) is a central cytokine that drives the inflammation in RA; hence inhibition of TNF-α offers an attractive treatment strategy in RA. The introduction of TNF-α inhibitors, a class of biologic DMARDs, has dramatically changed the treatment of RA as these are highly effective therapies. Medication-related adverse events remain a major problem in health care. This is true of the TNF-α antagonists as well, with particular concerns about increased risks of infections and malignancy. Because clinical trials performed prior to medication approval are limited by the number and clinical complexity of participants and the duration of the trials, post-marketing surveillance is critical in identifying adverse events. In order to better clarify the safety issues related to the use of TNF-α inhibitors in RA, several studies using large observational registries along with pooled meta-analyses of these studies have been published. This review will summarize the data from these recent studies on the question of malignancy risk associated with TNF-α inhibitor use in RA. It is comforting that the data from these studies do not support an increased risk of cancer, except non-melanoma skin cancer, with the use of TNF-α antagonists in adults with RA.


Assuntos
Antirreumáticos/efeitos adversos , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Neoplasias/induzido quimicamente , Vigilância de Produtos Comercializados , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Humanos , Fatores de Risco , Fator de Necrose Tumoral alfa/metabolismo
11.
Rheum Dis Clin North Am ; 37(4): 593-606, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22075199

RESUMO

It is essential to be aware of both neoplastic and paraneoplastic vasculitides, vasculopathy, and hypercoagulability, considering the importance of an accurate diagnosis and timely treatment of the underlying malignancy. Characteristics such as the type of vasculitis, age, gender, atypical presentation, and lack of response to common therapies should prompt investigation for an occult malignancy, whereas vasculitis such as GPA require due malignancy vigilance given a significantly increased risk of malignancy at the time of diagnosis and in the following years. Vasculopathies are rarer than vasculitides, but are associated with specific malignancies and, in the context of such malignancies, should be kept in mind. Hypercoagulability is a well-documented neoplastic phenomenon with an increased risk of thrombosis in the setting of positive aPLs. Most neoplastic and paraneoplastic vascular syndromes require no specific treatment outside of treatment of the underlying malignancy. The two key exceptions are PACNS, because of its poor prognosis, and erythromelalgia, in which aspirin is an effective agent.


Assuntos
Neoplasias/complicações , Síndromes Paraneoplásicas/etiologia , Trombofilia/etiologia , Vasculite/etiologia , Anticorpos Antinucleares/imunologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Neoplasias/diagnóstico , Neoplasias/fisiopatologia , Síndromes Paraneoplásicas/diagnóstico , Síndromes Paraneoplásicas/fisiopatologia , Trombofilia/diagnóstico , Trombofilia/fisiopatologia , Vasculite/diagnóstico , Vasculite/fisiopatologia
12.
Mol Cells ; 27(1): 75-81, 2009 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-19214436

RESUMO

The Arabidopsis gene AtLEC (At3g15356) gene encodes a putative 30-kDa protein with a legume lectin-like domain. Likely to classic legume lectin family of genes, AtLEC is expressed in rosette leaves, primary inflorescences, and roots, as observed in Northern blot analysis. The accumulation of AtLEC transcript is induced very rapidly, within 30 min, by chitin, a fungal wall-derived oligosaccharide elictor of the plant defense response. Transgenic Arabidopsis carrying an AtLEC promoter-driven beta-glucuronidase (GUS) construct exhibited GUS activity in the leaf veins, secondary inflorescences, carpel heads, and silique receptacles, in which no expression could be seen in Northern blot analysis. This observation suggests that AtLEC expression is induced transiently and locally during developmental processes in the absence of an external signal such as chitin. In addition, mechanically wounded sites showed strong GUS activity, indicating that the AtLEC promoter responds to jasmonate. Indeed, methyl jasmonate and ethylene exposure induced AtLEC expression within 3-6 h. Thus, the gene appears to play a role in the jasmonate-/ethylene-responsive, in addition to the chitin-elicited, defense responses. However, chitin-induced AtLEC expression was also observed in jasmonate-insensitive (coi1) and ethylene-insensitive (etr1-1) Arabidopsis mutants. Thus, it appears that chitin promotes AtLEC expression via a jasmonate- and/or ethylene-independent pathway.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Quitina/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Lectinas de Plantas/genética , Regulação para Cima/efeitos dos fármacos , Acetatos/farmacologia , Sequência de Aminoácidos , Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/química , Northern Blotting , Ciclopentanos/farmacologia , Etilenos/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Glucuronidase/metabolismo , Dados de Sequência Molecular , Especificidade de Órgãos/efeitos dos fármacos , Oxilipinas/farmacologia , Lectinas de Plantas/química , Transdução de Sinais/efeitos dos fármacos
13.
Exp Mol Med ; 39(3): 395-401, 2007 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-17603294

RESUMO

It is well known that exercise can have beneficial effects on insulin resistance by activation of glucose transporter. Following up our previous report that caveolin-1 plays an important role in glucose uptake in L6 skeletal muscle cells, we examined whether exercise alters the expression of caveolin-1, and whether exercise-caused changes are muscle fiber and exercise type specific. Fifty week-old Sprague Dawley (SD) rats were trained to climb a ladder and treadmill for 8 weeks and their soleus muscles (SOL) and extensor digitorum longus muscles (EDL) were removed after the last bout of exercise and compared with those from non-exercised animals. We found that the expression of insulin related proteins and caveolins did not change in SOL muscles after exercise. However, in EDL muscles, the expression of insulin receptor beta (IR beta) and glucose transporter-4 (GLUT-4) as well as phosphorylation of AKT and AMPK increased with resistance exercise but not with aerobic exercise. Also, caveolin-1 and caveolin-3 increased along with insulin related proteins only in EDL muscles by resistance exercise. These results suggest that upregulation of caveolin-1 in the skeletal muscle is fiber specific and exercise type specific, implicating the requirement of the specific mode of exercise to improve insulin sensitivity.


Assuntos
Caveolina 1/biossíntese , Insulina/fisiologia , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/fisiologia , Condicionamento Físico Animal , Proteínas Quinases Ativadas por AMP , Animais , Caveolina 3/metabolismo , Feminino , Transportador de Glucose Tipo 4/biossíntese , Complexos Multienzimáticos/metabolismo , Músculo Esquelético/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor de Insulina/biossíntese , Regulação para Cima
14.
Eur J Appl Physiol ; 99(2): 193-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17089153

RESUMO

Both regular physical exercise and carnitine supplementation exert a role in energy metabolism and may improve endurance capacity. We investigated whether a combination of long-term carnitine ingestion and exercise training reveals any interactive effects on cytosolic fatty acid-binding protein (FABPc) expression and beta-hydroxyacyl CoA dehydrogenase (beta-HAD) activity in human skeletal muscle. Twenty-eight untrained healthy males randomly divided into four experimental groups: a placebo (CON; n = 7), exercise training (ET; n = 7, 40 min session(-1), five times per week at 60% VO2max), carnitine supplementation (CS; n = 7, 4 g day(-1)), and exercise training and carnitine supplementation (CT; n = 7). Before and after 6-week treatment, muscle biopsy samples were taken from the vastus lateralis. Nonesterified carnitine and acid-soluble acylcarnitine concentrations were increased in CT (P < 0.05), and serum triacylglycerol concentration was elevated almost twofold in ET and CT (P < 0.05). No interactive effects in FABPc expression were shown from any of treatment groups. Although FABPc increased by 54% in ET compared to CON, it failed to reach statistical significance. In addition, there was no change in FABPc expression from any of experimental groups. Similar trends with FABPc contents were demonstrated in beta-HAD activity. It is concluded that the combination of exercise training and L-carnitine supplementation does not augment in FABPc expression and beta-HAD activity in human skeletal muscle indicating that combined treatment does not exert additive effect in fat metabolism. Thus L-carnitine supplementation would be unlikely to be associated with the enhanced exercise performance.


Assuntos
3-Hidroxiacil-CoA Desidrogenases/metabolismo , Carnitina/farmacologia , Suplementos Nutricionais , Proteínas de Ligação a Ácido Graxo/metabolismo , Músculo Esquelético/efeitos dos fármacos , Resistência Física/fisiologia , Carnitina/metabolismo , Exercício Físico/fisiologia , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Fibras Musculares de Contração Rápida/efeitos dos fármacos , Fibras Musculares de Contração Lenta/efeitos dos fármacos , Músculo Esquelético/metabolismo , Fenótipo , Fatores de Tempo
15.
Bioorg Chem ; 31(6): 425-36, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14613764

RESUMO

Cathelicidins are a gene family of antimicrobial peptides produced as inactive precursors. Signal peptidase removes the N-terminal signal sequence, while peptidylglycine alpha-amidating monooxygenase often amidates and cleaves the C-terminal region. Removal of the cathelin domain liberates the active antimicrobial peptide. For mammalian sequences, this cleavage usually occurs through the action of elastase, but other tissue-specific processing enzymes may also operate. Once released, these bioactive peptides are susceptible to proteolytic degradation. We propose that some mature cathelicidins are naturally resistant to proteases due to their unusual primary structures. Among mammalian cathelicidins, proline-rich sequences should resist attack by serine proteases because proline prevents cleavage of the scissile bond. In hagfish cathelicidins, the unusual amino acid bromotryptophan may make the active peptides less susceptible to proteolysis for steric reasons. Such protease resistance could extend the pharmacokinetic lifetimes of cathelicidins in vivo, sustaining antimicrobial activity.


Assuntos
Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Inibidores de Cisteína Proteinase/química , Endopeptidases/metabolismo , Família Multigênica , Triptofano/análogos & derivados , Sequência de Aminoácidos , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Arginina/química , Sítios de Ligação , Catelicidinas , Endopeptidases/química , Feiticeiras (Peixe) , Humanos , Oxigenases de Função Mista/metabolismo , Dados de Sequência Molecular , Complexos Multienzimáticos/metabolismo , Prolina/química , Sinais Direcionadores de Proteínas , Proteínas/química , Proteínas/metabolismo , Homologia de Sequência de Aminoácidos , Triptofano/química , Triptofano/metabolismo
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