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1.
Cell Commun Signal ; 22(1): 353, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970072

RESUMO

Copper is a crucial trace element that plays a role in various pathophysiological processes in the human body. Copper also acts as a transition metal involved in redox reactions, contributing to the generation of reactive oxygen species (ROS). Under prolonged and increased ROS levels, oxidative stress occurs, which has been implicated in different types of regulated cell death. The recent discovery of cuproptosis, a copper-dependent regulated cell death pathway that is distinct from other known regulated cell death forms, has raised interest to researchers in the field of cancer therapy. Herein, the present work aims to outline the current understanding of cuproptosis, with an emphasis on its anticancer activities through the interplay with copper-induced oxidative stress, thereby providing new ideas for therapeutic approaches targeting modes of cell death in the future.


Assuntos
Antineoplásicos , Cobre , Estresse Oxidativo , Cobre/metabolismo , Humanos , Estresse Oxidativo/efeitos dos fármacos , Antineoplásicos/farmacologia , Animais , Espécies Reativas de Oxigênio/metabolismo , Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia
2.
Oral Oncol ; 154: 106864, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38824812

RESUMO

OBJECTIVE: To compare the changes in the sinonasal mucosa microbiome in patients with nasopharyngeal carcinoma (NPC) before and after radiotherapy (RT), and to explore the pathogenesis of post-irradiation chronic rhinosinusitis (PI-CRS) and its association with dysbiosis. STUDY DESIGN: Prospective cohort study. SETTING: Unicenter, Tertiary referral hospital. METHODS: Included patients newly diagnosed with NPC. Samples of ostiomeatal complex mucosa were collected before and after RT. Microbiome analysis was conducted using 16S rRNA sequencing, and statistical analysis was performed. Subgroup analyses based on RT modality (proton therapy or photon therapy) RESULTS: Total of 18 patients were enrolled in the study, with 62.1% receiving intensity-modulated proton therapy (IMPT). Corynebacterium was the most dominant genus identified in both the pre- and post-RT groups, with a visible increase in Staphylococcus and a decrease in Fusobacterium genus in post-RT group. Alpha-diversity did not significantly differ between groups, although the beta-diversity analysis revealed a dispersed microbiota in the post-RT group. The functional prediction indicated a higher relative abundance of taxonomies associated with biofilm formation in the post-RT group. The subgroup analysis revealed the above changes to be more significant in patients who received photon therapy (Intensity modulated radiation therapy, IMRT). CONCLUSIONS: This is the first study to analyze the microbiome of patients with NPC after IMPT. We identified similarities between the post-RT microenvironment and that reported in patients with CRS, with a more apparent change noted in patients treated with IMRT. Further investigation is required to further elucidate the pathogenesis of PI-CRS and its relationship to post-RT dysbiosis, particularly IMPT.


Assuntos
Disbiose , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Masculino , Feminino , Disbiose/microbiologia , Disbiose/etiologia , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/radioterapia , Carcinoma Nasofaríngeo/microbiologia , Projetos Piloto , Estudos Prospectivos , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/microbiologia , Adulto , Idoso , Microbiota/efeitos da radiação , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos
3.
Biomedicines ; 12(3)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38540122

RESUMO

Lidocaine, a local anesthetic widely used in dentistry, is esteemed for its efficacy and safety. Recent research reveals its additional role in modulating the immune system, and particularly in reducing inflammation crucial for protecting tooth-supporting tissues. Notably, monocytes and macrophages, essential cellular components overseeing various physiological and pathological processes, stand as potential mediators of lidocaine's effects. Therefore, this study aimed to investigate how lidocaine influences cell behavior using RNA sequencing. To investigate the effect of lidocaine on THP-1 cells' behavior, we performed an MTT assay and RNA-Seq along with qPCR analyses to evaluate the transcriptomic and proteomic changes in THP-1 cells. Our results showed that a high dose of lidocaine (>1 mM) had a significant cytotoxic effect on THP-1 cells. However, a lidocaine dose lower than 0.5 mM induced a mixed anti-inflammatory profile by significantly upregulating tissue remodeling (GDF15, FGF7, HGF, COL4A3, COL8A2, LAMB2, LAMC2, PDGFRA, and VEGFA) and through the resolution of inflammation (Cpeb4, Socs1, Socs2, Socs3, Dusp1, Tnfaip3, and Gata3) gene cassettes. This study explores the effect of lidocaine on the THP-1 in the M2-like healing phenotype and provides potential applications of lidocaine's therapeutic effectiveness in dental tissue repair.

4.
J Pers Med ; 13(9)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37763136

RESUMO

BACKGROUND: Incidence of fungal rhinosinusitis has increased in recent few years. We investigated the differences in microbiological findings between patients with fungal and non-fungal rhinosinusitis by growing microbiological cultures from samples obtained from sinus surgery. METHODS: Using the Chang Gung Research Database, we enrolled all chronic rhinosinusitis (CRS) patients who had ever undergone sinus surgery from 2001 to 2019 and had microbiological culture during sinus surgery. Enrolled patients were divided into fungal and non-fungal groups, based on fungal culture and surgical pathology. RESULTS: A total of 898 patients were diagnosed with fungal rhinosinusitis and 2884 with non-fungal rhinosinusitis. The fungal group had a higher age distribution (56.9 ± 13.1 vs. 47.0 ± 14.9), a larger proportion of females (62.4% vs. 37.0%), more unilateral lesions (80.4% vs. 41.6%), a lower incidence of the need for revision surgery (3.6% vs. 6.0%, p = 0.004), and a higher proportion of Pseudomonas aeruginosa in the culture (14.3% vs. 4.6%, p < 0.001). CONCLUSIONS: This large-scale study showed that Pseudomonas aeruginosa are more commonly found in patients with fungal rhinosinusitis and in patients who needed revision surgery, suggesting that efforts aimed at eliminating Pseudomonas are needed in order to improve the disease outcomes of patients with fungal rhinosinusitis.

5.
Cancer Cell Int ; 23(1): 212, 2023 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-37743493

RESUMO

BACKGROUND: Research studies have demonstrated that Midkine (MDK) can influence the expression and activity of Renin-angiotensin system (RAS) components. Angiotensin II is involved in tumor growth and angiogenesis in different cancers. We previously observed Angiotensin II receptor blockers (ARBs) improve the survival rates of patients with oral cancers. These findings have prompted us to investigate whether MDK can influence the RAS pathway, mainly through its association with angiotensin II type 1 receptor (AT1R), which contributes to the observed poor prognosis in head and neck squamous cell carcinoma (HNSCC) patients. METHODS: MDK and AT1R expressions were examined in 150 HNSCC patients post-operation by immunohistochemical staining between 1 January 2010 and 31 December 2016. We tested the over-expression and silencing of MDK to evaluate the AT1R expression and functional biological assays in HNSCC cell lines HSC-3 and SAS. RESULTS: Positive expression of MDK is correlated with positive AT1R expression. MDK predicted poor NSCC patients' survival. Silencing MDK could suppress AT1R and pAKT expression and reduce the growth, migration, and invasion of HNSCC cells. ARB also inhibits MDK stimulating HNSCC cell proliferation. Overexpression of MDK could upregulate AT1R and pAKT. CONCLUSIONS: MDK is an independent prognostic factor of HNSCC post-operation, and AT1R regulates HNSCC cell growth, invasion, and migration. Positive MDK and AT1R expressions are highly correlated. Mechanistically, the interaction between MDK and AT1R is crucial for MDK-mediated cell viability, and inhibiting AT1R can effectively counteract or abolish these effects. Furthermore, MDK exerts a regulatory role in the expression of AT1R, as well as in the growth and motility of HNSCC cells. These findings highlight the involvement of the interaction between MDK, AT1R, and the pAkt signaling pathways in HNSCC cell viability growth.

6.
Front Oncol ; 12: 1001126, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330492

RESUMO

Oral cancer, constituted up to 90% by squamous cell carcinomas, is a significant health burden globally. Grape seed proanthocyanidins (PA) have been suggested as a potential chemopreventive agent for oral cancer. However, their efficacy can be restricted due to the low bioavailability and bioaccessibility. Inspired by sandcastle worm adhesive, we adapted the concept of complex coacervation to generate a new type of drug delivery platform. Complex coacervates are a dense liquid phase formed by the associative separation of a mixture of oppositely charged polyelectrolytes, can serve as a drug delivery platform to protect labile cargo. In this study, we developed a complex coacervates-based delivery of PA. The release kinetics was measured, and anticancer effects were determined in two human tongue squamous cell carcinoma cell lines. The results showed that complex coacervate successfully formed and able to encapsulate PA. Additionally, PA were steadily released from the system in a pH-dependent manner. The drug delivery system could significantly inhibit the cell proliferation, migration, and invasion of cancer cells. Moreover, it could markedly reduce the expression of certain matrix metalloproteinases (MMP-2, 9, and 13) crucial to metastatic processes. We also found that suppression of protein kinase B (Akt) pathway might be the underlying mechanism for these anticancer activities. Taken together, complex coacervates-based delivery of PA can act as an effective anticancer approach for oral cancer therapy.

7.
Biochem Pharmacol ; 201: 115099, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35617999

RESUMO

Periodontal diseases are prevalent worldwide. Lipoteichoic acid (LTA), a major component of gram-positive bacteria, may play a key role in periodontally inflammatory diseases. Carbon monoxide (CO) is a critical messenger in many biological processes. It can elicit various biological properties, especially anti-inflammatory effects. As the straight administration of CO remains difficult, CO-releasing molecules (CO-RMs) are emerging as promising alternatives. To explore the pharmacological actions and signaling pathways of CO battling LTA-induced periodontal inflammation, this study investigated the cytoprotective effects of CORM-2 against the adhesion of THP-1 monocytes to human gingival fibroblasts (HGFs) and the underlying molecular mechanism. After exposing HGFs to LTA with or without CORM-2 pretreatment, monocyte adhesion was determined. VCAM-1 and ICAM-1 expression in HGFs was measured by real-time PCR. To identify the signaling pathways of CO involved in the cytoprotective effects of CORM-2, HGFs underwent pharmacological or genetical interventions before LTA incubation. The expression and/or activity of possible regulatory molecules were determined. The release of pro-inflammatory cytokines, including IL-1ß, IL-6, and TNF-α, were measured using ELISA. The results showed that LTA increased cytokine production and upregulated VCAM-1 and ICAM-1 expression in HGFs, promoting monocyte adhesion. These events were dependent on TLR2/MyD88/TRAF6- and PI3K/Akt/NADPH oxidase/ROS-regulated NF-κB activation. CORM-2 inhibited LTA-induced inflammatory cascades in HGFs, in which CO seemed to be the hitman. To conclude, CO released from CORM-2 can prevent the LTA-stimulated HGFs from increasing VCAM-1 and ICAM-1 expression and promoting monocyte adhesion by inhibiting TLR2/MyD88/TRAF6 association and PI3K/Akt/NADPH oxidase/ROS signaling, both converge on the canonical NF-κB activation.


Assuntos
NF-kappa B , Compostos Organometálicos , Espécies Reativas de Oxigênio , Fator 6 Associado a Receptor de TNF , Receptor 2 Toll-Like , Molécula 1 de Adesão de Célula Vascular , Fibroblastos , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Lipopolissacarídeos , Fator 88 de Diferenciação Mieloide/metabolismo , NADPH Oxidases/metabolismo , NF-kappa B/metabolismo , Compostos Organometálicos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/metabolismo , Ácidos Teicoicos , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
8.
Cancers (Basel) ; 14(3)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35158969

RESUMO

Increasing clinical evidence supports the use of direct oral anticoagulants (DOACs) as a potential new therapeutic option for patients suffering from cancer-associated thromboembolism. However, the clinical impact of DOACs compared with traditional anticoagulants on the survival of patients with head and neck cancer has not been well studied. A total of 1025 patients diagnosed as having head and neck cancer, including 92 DOAC users, 113 warfarin users, and 820 nonusers of anticoagulants, were selected from the Chang Gung Research Database between January 2001 and December 2019. The patients were matched using the propensity-score method. The survival rates were estimated among the three groups using the Kaplan-Meier method. The protective effects and side effects of the two anticoagulants were compared using the chi-square test. The death rate (18 patients, 19.57%) in patients using DOACs was significantly lower than that in patients using warfarin (68 patients, 60.18%) and those not using any anticoagulant (403 patients, 49.15%). DOAC users had significantly better disease-specific survival (DSS) than warfarin users (p = 0.019) and those who did not use any anticoagulant (p = 0.03). Further, DOAC users had significantly higher overall survival (OS) rates than warfarin users and those who did not use any anticoagulant (p = 0.003). Patients with oropharyngeal and laryngeal cancer and DOAC users had a significantly lower hazard ratio for survival, whereas patients with American Joint Committee on Cancer stage IV disease and those receiving multidisciplinary treatment (e.g., surgery with radiotherapy or concurrent radiochemotherapy) had a significantly higher hazard ratio for survival. Among them, patients with laryngeal cancer (HR = 0.47, 95% CI = 0.26-0.86, p = 0.0134) and DOAC users (HR = 0.53, 95% CI = 0.29-0.98, p = 0.042) had the lowest hazard ratio from DSS analysis. Similarly, patients with laryngeal cancer (HR = 0.48, 95% CI = 0.30-0.76, p = 0.0018) and DOAC users (HR = 0.58, 95% CI = 0.36-0.93, p = 0.0251) had the lowest hazard ratio from OS analysis. As for the protective effects or side effects of anticoagulants, there were no significant differences in the occurrence rate of bleeding or ischemic events between DOAC and warfarin users. In our study, DOACs were found to be better than warfarin in terms of survival in patients with head and neck cancer. As regards thromboembolism prevention and side effects, DOACs were comparable to warfarin in our patients. DOACs can be a treatment choice or prophylaxis for tumor emboli in head and neck cancer patients and they might be a better choice than traditional anticoagulants according to the results of our study.

9.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445474

RESUMO

Otolaryngology (also known as ear, nose, and throat (ENT)) diseases can be significantly affected by the level of sex hormones, which indicates that sex differences affect the manifestation, pathophysiology, and outcomes of these diseases. Recently, increasing evidence has suggested that proinflammatory responses in ENT diseases are linked to the level of sex hormones. The sex hormone receptors are present on a wide variety of immune cells; therefore, it is evident that they play crucial roles in regulating the immune system and hence affect the disease progression of ENT diseases. In this review, we focus on how sex hormones, particularly estrogens, regulate ENT diseases, such as chronic rhinosinusitis, vocal fold polyps, thyroid cancer, Sjögren's syndrome, and head and neck cancers, from the perspectives of inflammatory responses and specialized proresolving mediator-driven resolution. This paper aims to clarify why considering sex differences in the field of basic and medical research on otolaryngology is a key component to successful therapy for both males and females in the future.


Assuntos
Estrogênios/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Inflamação/patologia , Rinite/patologia , Sinusite/patologia , Síndrome de Sjogren/patologia , Neoplasias da Glândula Tireoide/patologia , Animais , Progressão da Doença , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Inflamação/metabolismo , Otolaringologia , Rinite/metabolismo , Fatores Sexuais , Sinusite/metabolismo , Síndrome de Sjogren/metabolismo , Neoplasias da Glândula Tireoide/metabolismo
10.
PLoS One ; 12(11): e0187069, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29095857

RESUMO

Hyposalivation reduces the patient quality of life, as saliva is important for maintaining oral health. Current treatments for hyposalivation are limited to medications such as the muscarinic receptor agonists, pilocarpine and cevimeline. However, these therapies only provide temporary relief. Therefore, alternative therapies are essential to restore salivary gland function. An option is to use bioengineered scaffolds to promote functional salivary gland regeneration. Previous studies demonstrated that the laminin-111 protein is critical for intact salivary gland cell cluster formation and organization. However, laminin-111 protein as a whole is not suitable for clinical applications as some protein domains may contribute to unwanted side effects such as degradation, tumorigenesis and immune responses. Conversely, the use of synthetic laminin-111 peptides makes it possible to minimize the immune reactivity or pathogen transfer. In addition, it is relatively simple and inexpensive as compared to animal-derived proteins. Therefore, the goal of this study was to demonstrate whether a 20 day treatment with laminin-111-derived peptide conjugated fibrin hydrogel promotes tissue regeneration in submandibular glands of a wound healing mouse model. In this study, laminin-111-derived peptide conjugated fibrin hydrogel significantly accelerated formation of salivary gland tissue. The regenerated gland tissues displayed not only structural but also functional restoration.


Assuntos
Fibrina/química , Hidrogéis , Laminina/farmacologia , Peptídeos/farmacologia , Glândulas Salivares/efeitos dos fármacos , Animais , Feminino , Teste de Materiais , Camundongos , Camundongos Endogâmicos C57BL , Saliva/metabolismo , Glândulas Salivares/fisiologia , Proteínas e Peptídeos Salivares/metabolismo
11.
Adv Colloid Interface Sci ; 239: 88-96, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27393642

RESUMO

Sandcastle worms, Phragmatopoma californica (Fewkes), live along the western coast of North America. Individual worms build tubular shells under seawater by gluing together sandgrains and biomineral particles with a multipart, rapid-set, self-initiating adhesive. The glue comprises distinct sets of condensed, oppositely charged polyelectrolytic components-polyphosphates, polysulfates, and polyamines-that are separately granulated and stored at high concentration in distinct cell types. The pre-organized adhesive modules are secreted separately and intact, but rapidly fuse with minimal mixing and expand into a crack-penetrating complex fluid. Within 30s of secretion into seawater, the fluid adhesive transitions (sets) into a porous solid adhesive joint. The nano- and microporous structure of the foamy solid adhesive contributes to the strength and toughness of the adhesive joint through several mechanisms. A curing agent (catechol oxidase), co-packaged into both types of adhesive granules, covalently cross-links the adhesive and becomes a structural component of the final adhesive joint. The overall effectiveness of the granulated sandcastle glue is more a product of the cellular sorting and packaging mechanisms, the transition from fluid to solid following secretion, and its final biphasic porous structure as it is of its composition or any particular amino acid modification.


Assuntos
Transição de Fase , Poliquetos/química , Eletricidade Estática , Adesividade , Animais , Fenômenos Biomecânicos
12.
Physiol Rep ; 4(19)2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27694530

RESUMO

Sjögren's syndrome (SS) is an autoimmune disorder characterized by chronic inflammation and destruction of salivary and lacrimal glands leading to dry mouth and dry eyes, respectively. Currently, the etiology of SS is unknown and the current therapies have no permanent benefit; therefore, new approaches are necessary to effectively treat this condition. Resolvins are highly potent endogenous lipid mediators that are synthesized during the resolution of inflammation to restore tissue homeostasis. Previous studies indicate that the resolvin family member, RvD1, binds to the ALX/FPR2 receptor to block inflammatory signals caused by tumor necrosis factor-alpha (TNF-α) in the salivary epithelium. More recently, the corticosteroid, dexamethasone (DEX), was shown to be effective in reducing salivary gland inflammation. However, DEX, as with other corticosteroids, elicits adverse secondary effects that could be ameliorated when used in smaller doses. Therefore, we investigated whether the more stable aspirin-triggered (AT) epimer, AT-RvD1, combined with reduced doses of DEX is effective in treating TNF-α-mediated disruption of polarized rat parotid gland (Par-C10) epithelial cell clusters. Our results indicate that AT-RvD1 and DEX individually reduced TNF-α-mediated alteration in the salivary epithelium (i.e, maintained cell cluster formation, increased lumen size, reduced apoptosis, and preserved cell survival signaling responses) as compared to untreated cells. Furthermore, AT-RvD1 combined with a reduced dose of DEX produced stronger responses (i.e., robust salivary cell cluster formation, larger lumen sizes, further reduced apoptosis, and sustained survival signaling responses) as compared to those observed with individual treatments. These studies demonstrate that AT-RvD1 combined with DEX is highly effective in treating TNF-α-mediated disruption of salivary gland epithelium.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Terapia Combinada/métodos , Dexametasona/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Glucocorticoides/farmacologia , Glândulas Salivares/citologia , Síndrome de Sjogren/patologia , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Aspirina/administração & dosagem , Dexametasona/administração & dosagem , Ácidos Docosa-Hexaenoicos/administração & dosagem , Glucocorticoides/administração & dosagem , Inflamação/metabolismo , Ratos , Receptores de Lipoxinas/efeitos dos fármacos , Receptores de Lipoxinas/metabolismo , Glândulas Salivares/efeitos dos fármacos , Glândulas Salivares/patologia , Glândulas Salivares/ultraestrutura , Transdução de Sinais/fisiologia , Síndrome de Sjogren/tratamento farmacológico , Síndrome de Sjogren/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
13.
J R Soc Interface ; 12(112)2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26490632

RESUMO

Casemaker caddisfly (Hesperophylax occidentalis) larvae use adhesive silk fibres to construct protective shelters under water. The silk comprises a distinct peripheral coating on a viscoelastic fibre core. Caddisworm silk peroxinectin (csPxt), a haem-peroxidase, was shown to be glycosylated by lectin affinity chromatography and tandem mass spectrometry. Using high-resolution H2O2 and peroxidase-dependent silver ion reduction and nanoparticle deposition, imaged by electron microscopy, csPxt activity was shown to be localized in the peripheral layer of drawn silk fibres. CsPxt catalyses dityrosine cross-linking within the adhesive peripheral layer post-draw, initiated perhaps by H2O2 generated by a silk gland-specific superoxide dismutase 3 (csSOD3) from environmental reactive oxygen species present in natural water. CsSOD3 was also shown to be a glycoprotein and is likely localized in the peripheral layer. Using a synthetic fluorescent phenolic copolymer and confocal microscopy, it was shown that csPxt catalyses oxidative cross-linking to external polyphenolic compounds capable of diffusive interpenetration into the fuzzy peripheral coating, including humic acid, a natural surface-active polyphenol. The results provide evidence of enzyme-mediated covalent cross-linking of a natural bioadhesive to polyphenol conditioned interfaces as a mechanism of permanent adhesion underwater.


Assuntos
Artrópodes/química , Moléculas de Adesão Celular/química , Peroxidase/química , Seda/química , Animais , Catálise , Peróxido de Hidrogênio/química , Oxirredução , Prata/química
14.
Biomacromolecules ; 14(5): 1607-17, 2013 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-23530959

RESUMO

Tube-building sabellariid polychaetes have major impacts on the geology and ecology of shorelines worldwide. Sandcastle worms, Phragmatopoma californica (Fewkes), live along the western coast of North America. Individual sabellariid worms build tubular shells by gluing together mineral particles with a multipart polyelectrolytic adhesive. Distinct sets of oppositely charged components are packaged and stored in concentrated granules in separate cell types. Homogeneous granules contain sulfated macromolecules as counter-polyanion to polycationic Pc2 and Pc5 proteins, which become major components of the fully cured glue. Heterogeneous granules contain polyphosphoproteins, Pc3A/B, paired with divalent cations and polycationic Pc1 and Pc4 proteins. Both types of granules contain catechol oxidase that catalyzes oxidative cross-linking of L-DOPA. Co-secretion of catechol oxidase guarantees rapid and spatially homogeneous curing with limited mixing of the preassembled adhesive packets. Catechol oxidase remains active long after the glue is fully cured, perhaps providing an active cue for conspecific larval settlement.


Assuntos
Adesivos/química , Catecol Oxidase/química , Reagentes de Ligações Cruzadas/química , Levodopa/análogos & derivados , Levodopa/química , Poliquetos/enzimologia , Animais , Biocatálise , Catecol Oxidase/isolamento & purificação , Reagentes de Ligações Cruzadas/isolamento & purificação , Eletrólitos , Poliquetos/química
15.
J Exp Biol ; 215(Pt 2): 351-61, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22189779

RESUMO

The marine sandcastle worm bonds mineral particles together into underwater composite dwellings with a proteinaceous glue. The products of at least four distinct secretory cell types are co-secreted from the building organ to form the glue. Prominent hetereogeneous granules contain dense sub-granules of Mg and the (polyphospho)proteins Pc3A and B, as well as at least two polybasic proteins, Pc1 and Pc4, as revealed by immunolabeling with specific antibodies against synthetic peptides. Equally prominent homogeneous granules comprise at least two polybasic proteins, Pc2 and Pc5, localized by immunolabeling with anti-synthetic peptide antibodies. The components of the sub-micrometer granule types are unknown, though positive staining with a redox-sensitive dye suggests the contents include o-dihydroxy-phenylalanine (dopa). Quantitative PCR and in situ hybridization demonstrated that a tyrosinase-like enzyme with a signal peptide was highly expressed in both the heterogeneous and homogeneous granules. The contents of the granules are poorly mixed in the secreted mixture that forms the glue. Subsequent covalent cross-linking of the glue may be catalyzed by the co-secreted tyrosinase. The first three parapodia of the sandcastle worm also contain at least two distinct secretory tissues. The Pc4 protein was immunolocalized to the anterior secretory cells and the tryosinase-like gene was expressed in the posterior secretory cells, which suggests these proteins may have multiple roles.


Assuntos
Poliquetos/metabolismo , Poliquetos/ultraestrutura , Precursores de Proteínas/metabolismo , Adesivos , Sequência de Aminoácidos , Animais , Western Blotting , California , DNA Complementar/metabolismo , Perfilação da Expressão Gênica , Imuno-Histoquímica , Hibridização In Situ , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Poliquetos/química , Precursores de Proteínas/química , Proteínas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de Proteína
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