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1.
Heliyon ; 9(12): e22594, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38076095

RESUMO

Aim: The aim of this study was to assess the feasibility of targeted therapy of thyroid carcinoma, first exploring potential targets BRAF, EGFR and CD44v6 in patient material through immunohistochemistry and mutation analysis. Materials and methods: A patient cohort (n = 22) consisting of seven papillary (PTC), eight anaplastic (ATC) and seven follicular (FTC) thyroid carcinomas were evaluated. Additionally, eight thyroid carcinoma cells lines were analyzed for CD44v6-expression and sensitivity to the multi-kinase inhibitor sorafenib (Nexavar®), which targets numerous serine/threonine and tyrosine kinases, including the Raf family kinases. Targeted therapy using 131I-AbN44v6, a novel anti-CD44v6 antibody, and/or sorafenib was evaluated in 3D multicellular tumor spheroids. Results: Of the two cell surface proteins, EGFR and CD44v6, the latter was overexpressed in >80 % of samples, while EGFR-expression levels were moderate at best in only a few samples. BRAF mutations were more common in PTC patient samples than in ATC samples, while FTC samples did not harbor BRAF mutations. CD44v6-expression levels in the thyroid carcinoma cell lines were more heterogenous compared to patient samples, while BRAF mutational status was in line with the original tumor type. Monotherapy in 3D multicellular ATC tumor spheroids with either 131I-AbN44v6 or sorafenib resulted in delayed spheroid growth. The combination of 131I-AbN44v6 and sorafenib was the most potent and resulted in significantly impaired spheroid growth. Conclusion: This "proof of concept" targeted therapy study in the in vitro ATC 3D multicellular tumor spheroids indicated applicability of utilizing CD44v6 for molecular radiotherapy both as a monotherapy and in combination with sorafenib.

2.
Sci Rep ; 13(1): 20648, 2023 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-38001360

RESUMO

Molecular radiotherapy combines the advantages of systemic administration of highly specific antibodies or peptides and the localized potency of ionizing radiation. A potential target for molecular radiotherapy is the cell surface antigen CD44v6, which is overexpressed in numerous cancers, with limited expression in normal tissues. The aim of the present study was to generate and characterize a panel of human anti-CD44v6 antibodies and identify a suitable candidate for future use in molecular radiotherapy of CD44v6-expressing cancers. Binders were first isolated from large synthetic phage display libraries containing human scFv and Fab antibody fragments. The antibodies were extensively analyzed through in vitro investigations of binding kinetics, affinity, off-target binding, and cell binding. Lead candidates were further subjected to in vivo biodistribution studies in mice bearing anaplastic thyroid cancer xenografts that express high levels of CD44v6. Additionally, antigen-dependent tumor uptake of the lead candidate was verified in additional xenograft models with varying levels of target expression. Interestingly, although only small differences were observed among the top antibody candidates in vitro, significant differences in tumor uptake and retention were uncovered in in vivo experiments. A high-affinity anti-CD44v6 lead drug candidate was identified, mAb UU-40, which exhibited favorable target binding properties and in vivo distribution. In conclusion, a panel of human anti-CD44v6 antibodies was successfully generated and characterized in this study. Through comprehensive evaluation, mAb UU-40 was identified as a promising lead candidate for future molecular radiotherapy of CD44v6-expressing cancers due to its high affinity, excellent target binding properties, and desirable in vivo distribution characteristics.


Assuntos
Neoplasias , Humanos , Animais , Camundongos , Distribuição Tecidual , Neoplasias/patologia , Anticorpos Monoclonais/metabolismo , Linhagem Celular Tumoral
3.
Plast Reconstr Surg ; 150(2): 327-338, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35666152

RESUMO

BACKGROUND: Striae distensae are common disfiguring cutaneous lesions but lack effective treatments because of an incomplete understanding of their pathophysiology. Dermal fibroblasts likely play an important role. The authors investigate the cellular-molecular features distinguishing fibroblasts from human striae distensae and normal skin. The authors also develop a mouse model of striae distensae. METHODS: Human striae distensae and normal skin samples were compared for tensile strength and histologic structure. Fibroblasts from striae distensae and normal skin were isolated by fluorescence-activated cell sorting for gene expression analysis. Immunofluorescence staining and fluorescence-activated cell sorting were used to confirm gene expression data at the protein level. A mouse model of striae distensae formation was created by administering corticosteroids and mechanically loading the dorsal skin. RESULTS: Human striae distensae exhibited reduced tensile strength, more disordered collagen fibers, and epidermal atrophy compared to human normal skin. There were 296 up-regulated genes in striae distensae fibroblasts, including the profibrotic lineage and surface marker CD26. Up-regulated genes were involved in profibrotic and mechanoresponsive signaling pathways (TGFß and FAK-PI3-AKT-signaling). In contrast, 571 genes were down-regulated, including CD74 and genes of the AMPK pathway. Increased CD26 and decreased CD74 expression was confirmed by fluorescence-activated cell sorting and immunofluorescence. Similar cutaneous histologic and gene expression changes were induced in hypercortisolemic mice by mechanically loading the dorsal skin. CONCLUSIONS: Fibroblasts from human striae distensae exhibit increased profibrotic and decreased antifibrotic signaling. CD26 and CD74 are promising surface markers that may be targeted therapeutically. The authors' mouse model of striae distensae can be used as a platform to test the efficacy of potential therapeutic agents. CLINICAL RELEVANCE STATEMENT: Striae distensae are common disfiguring cutaneous lesions whose etiology remains elusive, which has hindered development of effective treatment strategies. Dermal fibroblasts likely play an important role. The authors sought to elucidate the key cellular-molecular pathways distinguishing fibroblasts in striae distensae from those in normal skin.


Assuntos
Estrias de Distensão , Animais , Dipeptidil Peptidase 4 , Modelos Animais de Doenças , Fibroblastos/metabolismo , Humanos , Camundongos , Transdução de Sinais , Pele/patologia
4.
Cleft Palate Craniofac J ; 59(3): 330-335, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33960204

RESUMO

OBJECTIVE: It is important for health care education materials to be easily understood by caretakers of children requiring craniofacial surgery. This study aimed to analyze the readability of Google search results as they pertain to "Cleft Palate Surgery" and "Palatoplasty." Additionally, the study included a search from several locations globally to identify possible geographic differences. DESIGN: Google searches of the terms "Cleft Palate Surgery" and "Palatoplasty" were performed. Additionally, searches of only "Cleft Palate Surgery" were run from several internet protocol addresses globally. MAIN OUTCOME MEASURES: Flesch-Kincaid Grade Level and Readability Ease, Gunning Fog Index, Simple Measure of Gobbledygook (SMOG) index, and Coleman-Liau Index. RESULTS: Search results for "Cleft Palate Surgery" were easier to read and comprehend compared to search results for "Palatoplasty." Mean Flesch-Kincaid Grade Level scores were 7.0 and 10.11, respectively (P = .0018). Mean Flesch-Kincaid Reading Ease scores were 61.29 and 40.71, respectively (P = .0003). Mean Gunning Fog Index scores were 8.370 and 10.34, respectively (P = .0458). Mean SMOG Index scores were 6.84 and 8.47, respectively (P = .0260). Mean Coleman-Liau Index scores were 12.95 and 15.33, respectively (P = .0281). No significant differences were found in any of the readability measures based on global location. CONCLUSIONS: Although some improvement can be made, craniofacial surgeons can be confident in the online information pertaining to cleft palate repair, regardless of where the search is performed from. The average readability of the top search results for "Cleft Palate Surgery" is around the seventh-grade reading level (US educational system) and compares favorably to other health care readability analyses.


Assuntos
Fissura Palatina , Letramento em Saúde , Cirurgia Bucal , Criança , Fissura Palatina/cirurgia , Compreensão , Humanos , Internet , Smog
5.
Adv Wound Care (New Rochelle) ; 11(10): 524-536, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34346243

RESUMO

Objective: Radiation therapy is commonplace for cancer treatment but often results in fibrosis and atrophy of surrounding soft tissue. Decellularized adipose matrices (DAMs) have been reported to improve these soft tissue defects through the promotion of adipogenesis. These matrices are decellularized by a combination of physical, chemical, and enzymatic methods to minimize their immunologic effects while promoting their regenerative effects. In this study, we aimed at exploring the regenerative ability of a DAM (renuva®; MTF biologics, Edison, NJ) in radiation-induced soft tissue injury. Approach: Fresh human lipoaspirate or DAM was injected into the irradiated scalp of CD-1 nude mice, and volume retention was monitored radiographically over 8 weeks. Explanted grafts were histologically assessed, and overlying skin was examined histologically and biomechanically. Irradiated human skin was also evaluated from patients after fat grafting or DAM injection. However, integrating data between murine and human skin in all cohorts is limited given the genetic variability between the two species. Results: Volume retention was found to be greater with fat grafts, though DAM retention was, nonetheless, appreciated at irradiated sites. Improvement in both mouse and human irradiated skin overlying fat and DAM grafts was observed in terms of biomechanical stiffness, dermal thickness, collagen density, collagen fiber networks, and skin vascularity. Innovation: This is the first demonstration of the use of DAMs for augmenting the regenerative potential of irradiated mouse and human skin. Conclusions: These findings support the use of DAMs to address soft tissue atrophy after radiation therapy. Morphological characteristics of the irradiated skin can also be improved with DAM grafting.


Assuntos
Tecido Adiposo , Pele , Animais , Atrofia/patologia , Fibrose , Humanos , Camundongos , Camundongos Nus , Pele/patologia
6.
J Cell Mol Med ; 25(21): 10028-10038, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34612609

RESUMO

The iron chelator, deferoxamine (DFO), has been shown to potentially improve dermal radiation-induced fibrosis (RIF) in mice through increased angiogenesis and reduced oxidative damage. This preclinical study evaluated the efficacy of two DFO administration modalities, transdermal delivery and direct injection, as well as temporal treatment strategies in relation to radiation therapy to address collateral soft tissue fibrosis. The dorsum of CD-1 nude mice received 30 Gy radiation, and DFO (3 mg) was administered daily via patch or injection. Treatment regimens were prophylactic, during acute recovery, post-recovery, or continuously throughout the experiment (n = 5 per condition). Measures included ROS-detection, histology, biomechanics and vascularity changes. Compared with irradiated control skin, DFO treatment decreased oxidative damage, dermal thickness and collagen content, and increased skin elasticity and vascularity. Metrics of improvement in irradiated skin were most pronounced with continuous transdermal delivery of DFO. In summary, DFO administration reduces dermal fibrosis induced by radiation. Although both treatment modalities were efficacious, the transdermal delivery showed greater effect than injection for each temporal treatment strategy. Interestingly, the continuous patch group was more similar to normal skin than to irradiated control skin by most measures, highlighting a promising approach to address detrimental collateral soft tissue injury following radiation therapy.


Assuntos
Desferroxamina/farmacologia , Derme/metabolismo , Derme/patologia , Derme/efeitos da radiação , Radiação Ionizante , Animais , Biomarcadores , Derme/irrigação sanguínea , Suscetibilidade a Doenças , Feminino , Fibrose , Camundongos , Microvasos/diagnóstico por imagem , Microvasos/metabolismo , Estresse Oxidativo , Síndrome da Fibrose por Radiação/etiologia , Síndrome da Fibrose por Radiação/metabolismo , Síndrome da Fibrose por Radiação/patologia , Espécies Reativas de Oxigênio/metabolismo
8.
J Tissue Eng Regen Med ; 15(12): 1105-1117, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34582109

RESUMO

Radiation therapy is effective for cancer treatment but may also result in collateral soft tissue contracture, contour deformities, and non-healing wounds. Autologous fat transfer has been described to improve tissue architecture and function of radiation-induced fibrosis and these effects may be augmented by enrichment with specific adipose-derived stromal cells (ASCs) with enhanced angiogenic potential. CD34+CD146+, CD34+CD146-, or CD34+ unfractionated human ASCs were isolated by flow cytometry and used to supplement human lipoaspirate placed beneath the scalp of irradiated mice. Volume retention was followed radiographically and fat grafts as well as overlying soft tissue were harvested after eight weeks for histologic and biomechanical analyses. Radiographic evaluation revealed the highest volume retention in fat grafts supplemented with CD34+CD146+ ASCs, and these grafts were also found to have greater histologic integrity than other groups. Irradiated skin overlying CD34+CD146+ ASC-enriched grafts was significantly more vascularized than other treatment groups, had significantly less dermal thickness and collagen deposition, and the greatest improvement in fibrillin staining and return of elasticity. Radiation therapy obliterates vascularity and contributes to scarring and loss of tissue function. ASC-enrichment of fat grafts with CD34+CD146+ ASCs not only enhances fat graft vascularization and retention, but also significantly promotes improvement in overlying radiation-injured soft tissue. This regenerative effect on skin is highly promising for patients with impaired wound healing and deformities following radiotherapy.


Assuntos
Tecido Adiposo/metabolismo , Diferenciação Celular , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Síndrome da Fibrose por Radiação , Pele , Tecido Adiposo/patologia , Animais , Feminino , Xenoenxertos , Humanos , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Síndrome da Fibrose por Radiação/metabolismo , Síndrome da Fibrose por Radiação/patologia , Síndrome da Fibrose por Radiação/terapia , Pele/metabolismo , Pele/patologia
9.
Sci Transl Med ; 13(609): eabb3312, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34516825

RESUMO

Pathologic skin scarring presents a vast economic and medical burden. Unfortunately, the molecular mechanisms underlying scar formation remain to be elucidated. We used a hypertrophic scarring (HTS) mouse model in which Jun is overexpressed globally or specifically in α-smooth muscle or collagen type I­expressing cells to cause excessive extracellular matrix deposition by skin fibroblasts in the skin after wounding. Jun overexpression triggered dermal fibrosis by modulating distinct fibroblast subpopulations within the wound, enhancing reticular fibroblast numbers, and decreasing lipofibroblasts. Analysis of human scars further revealed that JUN is highly expressed across the wide spectrum of scars, including HTS and keloids. CRISPR-Cas9­mediated JUN deletion in human HTS fibroblasts combined with epigenomic and transcriptomic analysis of both human and mouse HTS fibroblasts revealed that JUN initiates fibrosis by regulating CD36. Blocking CD36 with salvianolic acid B or CD36 knockout model counteracted JUN-mediated fibrosis efficacy in both human fibroblasts and mouse wounds. In summary, JUN is a critical regulator of pathological skin scarring, and targeting its downstream effector CD36 may represent a therapeutic strategy against scarring.


Assuntos
Antígenos CD36 , Cicatriz Hipertrófica , Proteínas Proto-Oncogênicas c-jun , Dermatopatias , Animais , Cicatriz Hipertrófica/patologia , Humanos , Camundongos , Pele/patologia , Dermatopatias/patologia
10.
J Cataract Refract Surg ; 47(5): 671-673, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32769750

RESUMO

Deep anterior lamellar keratoplasty is a widely adopted technique to treat pathologies of the cornea without endothelial cell involvement. This technique has several advantages including longer graft survival without endothelial rejection and lower doses of steroid administration. A transillumination technique was used to diagnose big bubble formation. A partial-thickness trephination was made, followed by superficial keratectomy and air injection into the stroma. Then, a vitreoretinal endoilluminator was used to illuminate the cornea and check for any signs of "full moon" or "waning moon," which corresponded to the shine of the big bubble from total internal reflection of light. Once the diagnosis was made, the remnant stroma was removed, and the donor cornea without endothelium was sutured. An advantage of this technique was that it allowed the diagnosis of big bubble even on an opaque or whitish emphysematous cornea when other methods could not be used.


Assuntos
Transplante de Córnea , Ceratocone , Córnea , Substância Própria , Lâmina Limitante Posterior , Humanos , Ceratocone/cirurgia , Transiluminação
11.
Sci Rep ; 10(1): 12346, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32704071

RESUMO

Radiation therapy can result in pathological fibrosis of healthy soft tissue. The iron chelator deferoxamine (DFO) has been shown to improve skin vascularization when injected into radiated tissue prior to fat grafting. Here, we evaluated whether topical DFO administration using a transdermal drug delivery system prior to and immediately following irradiation (IR) can mitigate the chronic effects of radiation damage to the skin. CD-1 nude immunodeficient mice were split into four experimental groups: (1) IR alone (IR only), (2) DFO treatment for two weeks after recovery from IR (DFO post-IR), (3) DFO prophylaxis with treatment through and post-IR (DFO ppx), or (4) no irradiation or DFO (No IR). Immediately following IR, reactive oxygen species and apoptotic markers were significantly decreased and laser doppler analysis revealed significantly improved skin perfusion in mice receiving prophylactic DFO. Six weeks following IR, mice in the DFO post-IR and DFO ppx groups had improved skin perfusion and increased vascularization. DFO-treated groups also had evidence of reduced dermal thickness and collagen fiber network organization akin to non-irradiated skin. Thus, transdermal delivery of DFO improves tissue perfusion and mitigates chronic radiation-induced skin fibrosis, highlighting a potential role for DFO in the treatment of oncological patients.


Assuntos
Desferroxamina/farmacologia , Derme/metabolismo , Lesões Experimentais por Radiação/prevenção & controle , Radiodermite/prevenção & controle , Animais , Derme/patologia , Feminino , Camundongos , Camundongos Nus , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/patologia , Radiodermite/metabolismo , Radiodermite/patologia
12.
Stem Cells Transl Med ; 9(11): 1401-1413, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32563212

RESUMO

Fat grafting can reduce radiation-induced fibrosis. Improved outcomes are found when fat grafts are enriched with adipose-derived stromal cells (ASCs), implicating ASCs as key drivers of soft tissue regeneration. We have identified a subpopulation of ASCs positive for CD74 with enhanced antifibrotic effects. Compared to CD74- and unsorted (US) ASCs, CD74+ ASCs have increased expression of hepatocyte growth factor, fibroblast growth factor 2, and transforming growth factor ß3 (TGF-ß3) and decreased levels of TGF-ß1. Dermal fibroblasts incubated with conditioned media from CD74+ ASCs produced less collagen upon stimulation, compared to fibroblasts incubated with media from CD74- or US ASCs. Upon transplantation, fat grafts enriched with CD74+ ASCs reduced the stiffness, dermal thickness, and collagen content of overlying skin, and decreased the relative proportions of more fibrotic dermal fibroblasts. Improvements in several extracellular matrix components were also appreciated on immunofluorescent staining. Together these findings indicate CD74+ ASCs have antifibrotic qualities and may play an important role in future strategies to address fibrotic remodeling following radiation-induced fibrosis.


Assuntos
Antígenos de Diferenciação de Linfócitos B/metabolismo , Fibrose/induzido quimicamente , Antígenos de Histocompatibilidade Classe II/metabolismo , Radioterapia/efeitos adversos , Tecido Adiposo/metabolismo , Humanos , Pele/patologia , Células Estromais/metabolismo
13.
Stem Cells Transl Med ; 9(11): 1389-1400, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32543083

RESUMO

Fat grafting is a surgical technique able to reconstruct and regenerate soft tissue. The adipose-derived stromal cells (ASCs) within the stromal vascular fraction are believed to drive these beneficial effects. ASCs are increasingly recognized to be a heterogeneous group, comprised of multiple stem and progenitor subpopulations with distinct functions. We hypothesized the existence of an ASC subpopulation with enhanced angiogenic potential. Human ASCs that were CD34+CD146+, CD34+CD146-, or CD34+ unfractionated (UF) were isolated by flow cytometry for comparison of expression of proangiogenic factors and endothelial tube-forming potential. Next, lipoaspirate was enriched with either CD34+CD146+, CD34+CD146-, CD34+ UF ASCs, or was not enriched, and grafted beneath the scalp skin of immunodeficient CD-1 Nude mice (10 000 cells/200 µL/graft). Fat retention was monitored radiographically more than 8 weeks and fat grafts were harvested for histological assessment of quality and vascularization. The CD34+CD146+ subpopulation comprised ~30% of ASCs, and exhibited increased expression of vascular endothelial growth factor and angiopoietin-1 compared to CD34+CD146- and CD34+ UF ASCs, and increased expression of fibroblast growth factor-2 compared to CD34+CD146- ASCs. The CD34+CD146+ subpopulation exhibited enhanced induction of tube-formation compared to CD34+CD146- ASCs. Upon transplantation, fat enriched CD34+CD146+ ASCs underwent less resorption and had improved histologic quality and vascularization. We have identified a subpopulation of CD34+ ASCs with enhanced angiogenic effects in vitro and in vivo, likely mediated by increased expression of potent proangiogenic factors. These findings suggest that enriching lipoaspirate with CD34+CD146+ ASCs may enhance fat graft vascularization and retention in the clinical setting.


Assuntos
Tecido Adiposo/transplante , Antígenos CD34/metabolismo , Antígeno CD146/metabolismo , Células Estromais/metabolismo , Animais , Humanos , Camundongos , Camundongos Nus
14.
Mar Drugs ; 18(4)2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32244488

RESUMO

Neglected Tropical Diseases (NTD) represent a serious threat to humans, especially for those living in poor or developing countries. Almost one-sixth of the world population is at risk of suffering from these diseases and many thousands die because of NTDs, to which we should add the sanitary, labor and social issues that hinder the economic development of these countries. Protozoan-borne diseases are responsible for more than one million deaths every year. Visceral leishmaniasis, Chagas disease or sleeping sickness are among the most lethal NTDs. Despite not being considered an NTD by the World Health Organization (WHO), malaria must be added to this sinister group. Malaria, caused by the apicomplexan parasite Plasmodium falciparum, is responsible for thousands of deaths each year. The treatment of this disease has been losing effectiveness year after year. Many of the medicines currently in use are obsolete due to their gradual loss of efficacy, their intrinsic toxicity and the emergence of drug resistance or a lack of adherence to treatment. Therefore, there is an urgent and global need for new drugs. Despite this, the scant interest shown by most of the stakeholders involved in the pharmaceutical industry makes our present therapeutic arsenal scarce, and until recently, the search for new drugs has not been seriously addressed. The sources of new drugs for these and other pathologies include natural products, synthetic molecules or repurposing drugs. The most frequent sources of natural products are microorganisms, e.g., bacteria, fungi, yeasts, algae and plants, which are able to synthesize many drugs that are currently in use (e.g. antimicrobials, antitumor, immunosuppressants, etc.). The marine environment is another well-established source of bioactive natural products, with recent applications against parasites, bacteria and other pathogens which affect humans and animals. Drug discovery techniques have rapidly advanced since the beginning of the millennium. The combination of novel techniques that include the genetic modification of pathogens, bioimaging and robotics has given rise to the standardization of High-Performance Screening platforms in the discovery of drugs. These advancements have accelerated the discovery of new chemical entities with antiparasitic effects. This review presents critical updates regarding the use of High-Throughput Screening (HTS) in the discovery of drugs for NTDs transmitted by protozoa, including malaria, and its application in the discovery of new drugs of marine origin.


Assuntos
Antiprotozoários/farmacologia , Organismos Aquáticos/química , Produtos Biológicos/farmacologia , Infecções por Euglenozoa/tratamento farmacológico , Malária Falciparum/tratamento farmacológico , Doenças Negligenciadas/tratamento farmacológico , Animais , Antiprotozoários/uso terapêutico , Produtos Biológicos/uso terapêutico , Descoberta de Drogas , Resistência a Medicamentos , Infecções por Euglenozoa/parasitologia , Ensaios de Triagem em Larga Escala , Humanos , Malária Falciparum/parasitologia , Doenças Negligenciadas/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium malariae/efeitos dos fármacos , Plasmodium malariae/patogenicidade , Trypanosomatina/efeitos dos fármacos
15.
Bioorg Med Chem Lett ; 30(1): 126760, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31767266

RESUMO

In this study, six curcuminoids containing a tert-butoxycarbonyl (Boc) piperidone core were successfully synthesized, five of them are novel compounds reported here for the first time. These compounds were prepared through an aldolic condensation by adding tetrahydropyranyl-protected benzaldehydes or substituted benzaldehyde to a reaction mixture containing 4-Boc-piperidone and lithium hydroxide in an alcoholic solvent. A 44-94% yield was obtained supporting the developed methodology as a good strategy for the synthesis of 4-Boc-piperidone chalcones. Cytotoxic activity against LoVo and COLO 205 human colorectal cell lines was observed at GI50 values that range from 0.84 to 34.7 µg/mL, while in PC3 and 22RV1 human prostate cancer cell lines, GI50 values ranging from 17.1 to 22.9 µg/mL were obtained. Results from biochemical assays suggest that the cytotoxicity of the 4-Boc-piperidone chalcones can be linked to their ability to induce apoptosis, decrease the activity of NFκB and cellular proliferation. Our findings strongly support the potential of Boc-piperidone chalcones as novel cytotoxic agents against highly-metastatic cancer cells.


Assuntos
Antineoplásicos/uso terapêutico , Chalconas/síntese química , Neoplasias/tratamento farmacológico , Piperidonas/síntese química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Relação Estrutura-Atividade
16.
Stem Cells ; 38(3): 382-389, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31793745

RESUMO

The aim of this study was to explore the therapeutic effects of fat grafting on radiation-induced hind limb contracture. Radiation therapy (RT) is used to palliate and/or cure a range of malignancies but causes inevitable and progressive fibrosis of surrounding soft tissue. Pathological fibrosis may lead to painful contractures which limit movement and negatively impact quality of life. Fat grafting is able to reduce and/or reverse radiation-induced soft tissue fibrosis. We explored whether fat grafting could improve extensibility in irradiated and contracted hind limbs of mice. Right hind limbs of female 60-day-old CD-1 nude mice were irradiated. Chronic skin fibrosis and limb contracture developed. After 4 weeks, irradiated hind limbs were then injected with (a) fat enriched with stromal vascular cells (SVCs), (b) fat only, (c) saline, or (d) nothing (n = 10/group). Limb extension was measured at baseline and every 2 weeks for 12 weeks. Hind limb skin then underwent histological analysis and biomechanical strength testing. Irradiation significantly reduced limb extension but was progressively rescued by fat grafting. Fat grafting also reduced skin stiffness and reversed the radiation-induced histological changes in the skin. The greatest benefits were found in mice injected with fat enriched with SVCs. Hind limb radiation induces contracture in our mouse model which can be improved with fat grafting. Enriching fat with SVCs enhances these beneficial effects. These results underscore an attractive approach to address challenging soft tissue fibrosis in patients following RT.


Assuntos
Tecido Adiposo/transplante , Contratura/etiologia , Membro Posterior/patologia , Lesões Experimentais por Radiação/terapia , Animais , Feminino , Humanos , Camundongos , Camundongos Nus
17.
J Biol Chem ; 293(43): 16923-16930, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30201608

RESUMO

Bacterial conjugation is a key mechanism by which bacteria acquire antibiotic resistance. Therefore, conjugation inhibitors (COINs) are promising compounds in the fight against the spread of antibiotic resistance genes among bacteria. Unsaturated fatty acids (uFAs) and alkynoic fatty acid derivatives, such as 2-hexadecanoic acid (2-HDA), have been reported previously as being effective COINs. The traffic ATPase TrwD, a VirB11 homolog in plasmid R388, is the molecular target of these compounds, which likely affect binding of TrwD to bacterial membranes. In this work, we demonstrate that COINs are abundantly incorporated into Escherichia coli membranes, replacing palmitic acid as the major component of the membrane. We also show that TrwD binds palmitic acid, thus facilitating its interaction with the membrane. Our findings also suggest that COINs bind TrwD at a site that is otherwise occupied by palmitic acid. Accordingly, molecular docking predictions with palmitic acid indicated that it shares the same binding site as uFAs and 2-HDA, although it differs in the contacts involved in this interaction. We also identified 2-bromopalmitic acid, a palmitate analog that inhibits many membrane-associated enzymes, as a compound that effectively reduces TrwD ATPase activity and bacterial conjugation. Moreover, we demonstrate that 2-bromopalmitic and palmitic acids both compete for the same binding site in TrwD. Altogether, these detailed findings open up a new avenue in the search for effective synthetic inhibitors of bacterial conjugation, which may be pivotal for combating multidrug-resistant bacteria.


Assuntos
Adenosina Trifosfatases/metabolismo , Alcinos/farmacologia , Antibacterianos/farmacologia , Conjugação Genética/efeitos dos fármacos , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Ácidos Graxos Insaturados/farmacologia , Ácido Palmítico/farmacologia , Alcinos/química , Sítios de Ligação , Cristalografia por Raios X , Escherichia coli/efeitos dos fármacos , Simulação de Acoplamento Molecular
18.
Curr Top Med Chem ; 18(5): 418-427, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29766807

RESUMO

INTRODUCTION: The first total synthesis of ω-phenyl Δ6 fatty acids (FA) and their cytotoxicity (A549) and leishmanicidal (L. infantum) activities are described. The novel 16-phenyl-6-hexadecynoic acid (1) and the known 16-phenylhexadecanoic acid (2) were synthesized in 7-8 steps with overall yields of 46 % and 41 %, respectively. The syntheses of the unprecedented 10-phenyl-6-decynoic acid (3), 10-cyclohexyl-6-decynoic acid (4) and 10-(4-methoxyphenyl)-6-decynoic acid (5) was also performed in 3 steps with 73-76 % overall yields. The use of lithium acetylide coupling enabled the 4-step synthesis of 10-phenyl-6Z-decenoic acid (6) with a 100 % cis-stereochemistry. The cytotoxicity of these novel FA was determined against A549 cells and L. infantum promastigotes and amastigotes. Among the ω-phenylated FA, the best cytotoxicity towards A549 was displayed by 1, with an IC50 of 18 ± 1 µM. On the other hand, among the C10 acids, the ω-cyclohexyl acid 4 presented the best cytotoxicity (IC50 = 40 ± 2 µM) towards A549. RESULTS: Based on caspase-3/7 studies neither of the FA induced apoptosis in A549, thus implying other mechanisms of cell death. CONCLUSION: The antileishmanial studies were performed with the top Leishmania donovani topoisomerase IB (LdTopIB) inhibitors, namely 1 and 2 (EC50 between 14 and 36 µM, respectively), acids that did not stabilize the cleavage complexes between LdTopIB and DNA. Acids 1 and 2 displayed cytotoxicity towards L. infantum amastigotes (IC50 = 3-6 µM) and L. infantum promastigotes (IC50 = 60- 70 µM), but low toxicity towards murine splenocytes. Our results identified 1 as the optimum ω- phenylated acid of the series.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antiprotozoários/síntese química , Antiprotozoários/farmacologia , Ácidos Graxos Ômega-6/síntese química , Ácidos Graxos Ômega-6/farmacologia , Leishmania infantum/efeitos dos fármacos , Inibidores da Topoisomerase I/farmacologia , Antineoplásicos/química , Antiprotozoários/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA Topoisomerases Tipo I/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ácidos Graxos Ômega-6/química , Humanos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Inibidores da Topoisomerase I/síntese química , Inibidores da Topoisomerase I/química
19.
Rev. Asoc. Argent. Ortop. Traumatol ; 82(1): 54-58, mar. 2017. []
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-842510

RESUMO

Introducción: El ortopedista se enfrenta a situaciones donde impera el sacrificio de la arteria radial, ya sea en el uso del árbol arterial radial como donante de tejido vascularizado o en situaciones donde la arteria radial es lesionada. El objetivo de este estudio fue determinar los cambios morfológicos y funcionales en la circulación de la mano luego del sacrificio de la arteria radial. Materiales y Métodos: Se realizó un estudio de corte transversal sobre la base de una revisión de historias clínicas de 41 pacientes de ambos sexos, sometidos a cirugía de revascularización miocárdica a quienes se les resecó la arteria radial para ser utilizada como injerto. Los pacientes fueron evaluados mediante ecografía bidimensional y Doppler comparativa de ambos antebrazos, oximetría de pulso del dedo índice de ambas manos en reposo y estrés por ejercicio, y centellografía de ambos miembros superiores en reposo y estrés. Se constataron los síntomas y signos subjetivos de intolerancia al frío y en situación de estrés luego del ejercicio. Los resultados fueron valorados estadísticamente. Resultados: Solo dos pacientes (4,8%) tuvieron síntomas de claudicación de la mano operada durante actividades intensas. La valoración comparativa de ambas manos por oximetría de pulso y de perfusión por centellografía no arrojó diferencias estadísticamente significativas. La diferencia fue estadísticamente significativa en la medición ecográfica del diámetro de ambas arterias cubitales. Conclusión: La perfusión de la mano luego del sacrificio de la arteria radial no se ve comprometida. Nivel de Evidencia: IV


Introduction: Orthopedists face situations in which the radial artery is sacrificed, either for its use as donor of vascularized tissue for coverage of soft tissue defects or in situations where the radial artery is injured. The aim of this study was to determine the morphological and/or functional changes in hand circulation after the radial artery is sacrificed. Methods: A cross-sectional study was conducted based on the review of medical records of 41 patients of both sexes who underwent cardiac revascularization surgery in which a radial artery graft was used. Patients were evaluated using twodimensional and Doppler ultrasound comparing both forearms, index finger pulse oximetry of both hands at rest and after stress, and scintigraphy of both upper limbs at rest and after stress. Statistical evaluation was performed. Results: Only two patients (4.8%) had symptoms of hand claudication during intense activities. Comparative assessment of both hands by pulse oximetry and perfusion scintigraphy yielded no statistically significant difference. There was a statistically significant difference in ultrasound measurement of the diameter of both ulnar arteries. Conclusion: Perfusion of the hand after the sacrifice of the radial artery is not compromised. Level of Evidence: IV


Assuntos
Adulto , Retalhos Cirúrgicos , Artéria Radial/cirurgia , Mãos
20.
Lipids ; 51(2): 245-56, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26694606

RESUMO

The novel fatty acids (2R,5Z,9Z)-2-methoxy-25-methyl-5,9-hexacosadienoic acid (1a) and (2R,5Z,9Z)-2-methoxy-24-methyl-5,9-hexacosadienoic acid (1b) were isolated in 80 % purity from the Caribbean sponge Asteropus niger by chloroform/methanol extraction followed by solvent partitioning and silica gel column chromatography. The compounds were characterized by utilizing a combination of gas chromatography-mass spectrometry, nuclear magnetic resonance, and circular dichroism. Acids 1a and 1b were not detected in the phospholipids (PtdCho and PtdIns) of the sponge, but rather as free FA and possibly in glycosylceramides. The mixtures of 1a and 1b displayed cytotoxicity towards THP-1 and HepG2 cells with EC50's between 41 and 35 µg/mL. Apoptosis was not the preferred mode of cell death induced by 1a-1b in the THP-1 cells. This implies other types of cytotoxicity mechanisms, such as membrane disruption and/or the inhibition (EC50 = 1.8 µg/mL) of the human topoisomerase IB enzyme (hTopIB), with a mechanism of inhibition different from the one displayed by camptothecin (CPT). In a separate experiment, the mixture of 1a and 1b also displayed cytotoxicity towards ex vivo mouse splenocytes infected with Leishmania infantum amastigotes (IC(50) = 0.17 mg/mL) and free living promastigotes (IC(50) = 0.34 mg/mL). It was also found that the FA were inhibitory of the Leishmania topoisomerase IB (LTopIB) with an EC(50) = 5.1 µg/mL. Taken together, 1a and 1b represent a new class of FA with potential as TopIB inhibitors that preferentially inhibit hTopIB over LTopIB.


Assuntos
DNA Topoisomerases/biossíntese , Ácidos Graxos Insaturados/química , Glicoesfingolipídeos/química , Leishmaniose Visceral/tratamento farmacológico , Poríferos/química , Animais , DNA Topoisomerases/química , Ácidos Graxos Insaturados/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Células Hep G2 , Humanos , Leishmania infantum/efeitos dos fármacos , Leishmania infantum/patogenicidade , Leishmaniose Visceral/parasitologia , Espectroscopia de Ressonância Magnética , Camundongos , Inibidores da Topoisomerase/química , Inibidores da Topoisomerase/farmacologia
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