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1.
Vopr Pitan ; 90(3): 110-116, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34264562

RESUMO

For decades, one of the most popular ideas in reducing the burden of cancer worldwide is the idea of cancer chemoprevention with low-toxic agents. There is an evidence that polyprenols (polyisoprenoid alcohols) are perspective agents for cancer chemoprevention. The aim of the study is to investigate anticancer activity of the polyprenol complex (the main polyprenols are prenol-14, prenol-15, prenol-16 and prenol-17) against prostate cancer (PCa) and its precursor (prostatic intraepithelial neoplasia, PIN). Material and methods. For induction of prostate carcinogenesis we used modified protocol of two-stage model. Mature male Wistar rats were administrated with single intravenous injection of N-methyl-N-nitrosourea and chronic intraperitoneal injections of four testosterone esters following surgical castration. Animals with an initial body weight of 328±39 g were randomized into 3 groups: experimental group (n=32) - animals received polyprenols complex 12.5 mg/kg per os diluted in vegetable oil 5 days a week; control group (n=38) - animals received vehicle (vegetable oil) 0.5 ml per os 5 days a week; intact group (n=12) - animals without intervention. Duration of the experiment was 56 weeks. At the end of the study and in euthanized animals in terminal state as well, the prostate and seminal vesicles were processed by histological technique and serial step sections of all lobes were assessed blindly by two independent pathologists. Incidence and multiplicity of precancerous lesion (PIN) and prostate tumors were calculated. Results. Compared with the control group, long-term consumption of polyprenols significantly reduced the overall incidence of PIN from 76.5 to 44.8% (р=0.0183; relative risk, RR=0.59; 95% CI 0.38-0.91), multiplicity of PIN per rat per group by 48.4% (р=0.0081), the incidence of PIN in 2 or 3 lobes of the prostate from 55.9 to 27.6% (р=0.0402), the incidence of PIN in the dorsolateral prostate from 70.6 to 41.4% (р=0.0240), the incidence of PIN in the ventral lobe from 47.1 to 20.7% (р=0.0362). The polyprenol complex exhibited a pronounced anticancer effect against induced prostate tumors. In the group of animals receiving the tested agent, there was a significant decrease in the total incidence of PCa from 64.7 to 34.5% (р=0.0234; RR=0.53; 95% CI 0.30-0.93), as well as the multiplicity of PCa per rat per group and per PIN carrier by 63.4% (р=0.0024) and by 30.6% (р=0.0240) respectively. In the polyprenols group we observed significant decrease in the incidence of prostate cancer in 2 or 3 lobes from 32.4 to 6.9% (р=0.0147) and the incidence of PCa in the dorsolateral prostate from 58.8 to 24.1% (р=0.0101). Oral administration of polyprenols provided a nonsignificant trend towards a decrease in the incidence of metastatic prostate cancer from 32.4 to 20.7% (р=0.3962). Conclusion. Chronic oral consumption of polyprenols from the needles of Picea abies L. and Pinus sylvestris L. (12.5 mg/kg per day) significantly suppresses the development of PIN and PCa induced by MNM and a mixture of testosterone esters in male Wistar rats. Despite the exploratory nature of the study, our results can serve the rationale for further investigation of polyprenols in prostate cancer chemoprevention trials.


Assuntos
Abies , Picea , Pinus sylvestris , Animais , Carcinogênese , Poliprenois , Próstata , Ratos , Ratos Wistar
2.
Sci Rep ; 11(1): 7461, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33811219

RESUMO

This study ascertained the accumulation of polyprenol from four Irish conifer species Picea sitchensis, Cedrus atlantica 'Glauca', Pinus sylvestris and Taxus baccata and one flowering tree Cotoneaster hybrida using supercritical fluid extraction with carbon dioxide (SFE-CO2) and solvent extraction. The effects of SFE-CO2 parameters such as temperature (ranged from 40 to 70 [Formula: see text]), pressure (ranged from 100 to 350 bars) and dynamic time (from 70 min to 7 h) were analysed on the extraction efficiency of polyprenol. Qualitative and quantitative analysis of polyprenol was examined using high-performance liquid chromatography. Results showed that P. sylvestris accumulated the highest polyprenol yield of 14.00  ± [Formula: see text]mg g-1 DW when extracted with hexane:acetone (1:1 v/v). However, with SFE-CO2 conditions of 200 bars, 70 [Formula: see text], 7 h, with absolute ethanol as a cosolvent with a flow rate of 0.05 ml min-1, P. sitchensis accumulated the highest polyprenol yield of 6.35 ± [Formula: see text] mg g-1DW. This study emphasised the potential application of SFE-CO2 in the extraction of polyprenol as an environmentally friendly method to be used in pharmaceutical and food industries.


Assuntos
Dióxido de Carbono/isolamento & purificação , Poliprenois/análise , Árvores/química , Cromatografia Líquida de Alta Pressão , Irlanda , Magnoliopsida/química , Extratos Vegetais/química , Pressão , Padrões de Referência , Especificidade da Espécie , Temperatura
3.
Biochem Genet ; 59(1): 62-82, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32767051

RESUMO

Development of efficient vectors for transfection is one of the major challenges in genetic engineering. Previous research demonstrated that cationic derivatives of polyisoprenoids (PTAI) may serve as carriers of nucleic acids. In the present study, the effectiveness of two PTAI-based formulations (PTAI-6-8 and 10-14) was investigated and compared to the commercial reagents. The purpose of applied gene therapy was to enhance the expression of vascular endothelial growth factor (VEGF-A) in the renal medulla of spontaneously hypertensive rats (SHR) and to test its potential as a novel antihypertensive intervention. In the first part of the study (in vitro), we confirmed that PTAI-based lipoplexes efficiently transfect XC rat sarcoma cells and are stable in 37 °C for 7 days. In the in vivo experiments, we administered selected lipoplexes directly to the kidneys of conscious SHR (via osmotic pumps). There were no blood pressure changes and VEGF-A level in renal medulla was significantly higher only for PTAI-10-14-based formulation. In conclusion, despite the promising results, we were not able to achieve VEGF-A expression level high enough to verify VEGF-A gene therapy usefulness in SHR. However, results of our study give important indications for the future development of PTAI-based DNA carriers and kidney-targeted gene delivery.


Assuntos
Pressão Sanguínea/genética , Terapia Genética/instrumentação , Vetores Genéticos , Hipertensão/terapia , Medula Renal/metabolismo , Poliprenois/química , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Linhagem Celular Tumoral , DNA/genética , Glucose/metabolismo , Hipertensão/genética , Masculino , Osmose , Ratos , Ratos Endogâmicos SHR , Transfecção
4.
Sci Rep ; 10(1): 13264, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32764679

RESUMO

The cis-polyisoprenoid lipids namely polyprenols, dolichols and their derivatives are linear polymers of several isoprene units. In eukaryotes, polyprenols and dolichols are synthesized as a mixture of four or more homologues of different length with one or two predominant species with sizes varying among organisms. Interestingly, co-occurrence of polyprenols and dolichols, i.e. detection of a dolichol along with significant levels of its precursor polyprenol, are unusual in eukaryotic cells. Our metabolomics studies revealed that cis-polyisoprenoids are more diverse in the malaria parasite Plasmodium falciparum than previously postulated as we uncovered active de novo biosynthesis and substantial levels of accumulation of polyprenols and dolichols of 15 to 19 isoprene units. A distinctive polyprenol and dolichol profile both within the intraerythrocytic asexual cycle and between asexual and gametocyte stages was observed suggesting that cis-polyisoprenoid biosynthesis changes throughout parasite's development. Moreover, we confirmed the presence of an active cis-prenyltransferase (PfCPT) and that dolichol biosynthesis occurs via reduction of the polyprenol to dolichol by an active polyprenol reductase (PfPPRD) in the malaria parasite.


Assuntos
Dolicóis/isolamento & purificação , Metabolômica/métodos , Plasmodium falciparum/crescimento & desenvolvimento , Vias Biossintéticas , Dolicóis/biossíntese , Regulação da Expressão Gênica no Desenvolvimento , Plasmodium falciparum/metabolismo , Poliprenois/isolamento & purificação , Poliprenois/metabolismo , Proteínas de Protozoários/genética
5.
Bioorg Med Chem ; 28(18): 115661, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32828427

RESUMO

Nucleoside derivatives, in particular those featuring uridine, are familiar components of the nucleoside family of bioactive natural products. The structural complexity and biological activities of these compounds have inspired research from organic chemistry and chemical biology communities seeking to develop novel approaches to assemble the challenging molecular targets, to gain inspiration for enzyme inhibitor development and to fuel antibiotic discovery efforts. This review will present recent case studies describing the total synthesis and biosynthesis of uridine natural products, and de novo synthetic efforts exploiting features of the natural products to produce simplified scaffolds. This research has culminated in the development of complementary strategies that can lead to effective uridine-based inhibitors and antibiotics. The strengths and challenges of the juxtaposing methods will be illustrated by examining select uridine natural products. Moreover, structure-activity relationships (SAR) for each natural product-inspired scaffold will be discussed, highlighting the impact on inhibitor development, with the aim of future uridine-based small molecule expansion.


Assuntos
Produtos Biológicos/síntese química , Inibidores Enzimáticos/síntese química , Uridina/síntese química , Antibacterianos/farmacologia , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Descoberta de Drogas , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Estrutura Molecular , Fosfatos/química , Poliprenois/química , Relação Estrutura-Atividade , Uridina/metabolismo , Uridina/farmacologia
6.
Annu Rev Biochem ; 89: 741-768, 2020 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-32569526

RESUMO

Complex carbohydrates are essential for many biological processes, from protein quality control to cell recognition, energy storage, and cell wall formation. Many of these processes are performed in topologically extracellular compartments or on the cell surface; hence, diverse secretion systems evolved to transport the hydrophilic molecules to their sites of action. Polyprenyl lipids serve as ubiquitous anchors and facilitators of these transport processes. Here, we summarize and compare bacterial biosynthesis pathways relying on the recognition and transport of lipid-linked complex carbohydrates. In particular, we compare transporters implicated in O antigen and capsular polysaccharide biosyntheses with those facilitating teichoic acid and N-linked glycan transport. Further, we discuss recent insights into the generation, recognition, and recycling of polyprenyl lipids.


Assuntos
Proteínas de Escherichia coli/química , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Glicolipídeos/biossíntese , Antígenos O/biossíntese , Poliprenois/metabolismo , Transferases (Outros Grupos de Fosfato Substituídos)/química , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Transporte Biológico , Carbono-Oxigênio Ligases/química , Carbono-Oxigênio Ligases/genética , Carbono-Oxigênio Ligases/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Glicosiltransferases/química , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Modelos Moleculares , Estrutura Secundária de Proteína , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Ácidos Teicoicos/metabolismo , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo
7.
Int J Nanomedicine ; 15: 2733-2749, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368052

RESUMO

Background: This study demonstrated an innovative formulation including the polyprenol (GBP) lipid and vitamin E-TPGS hybrid nanoparticles (NPs) which was aimed to control the transfer of betulinic acid (BA) and low-substituted hydroxyl fullerenol (C60(OH)n). Additionally, it developed BA-C60(OH)n-GBP-TPGS-NPs delivery system and researched the anti-hepatocellular carcinoma (HCC) effects. Materials and Methods: The NPs were prepared by nanoprecipitation with ultrasonic-assisted emulsification (UAE) method. It was characterized by scanning electronic microscopy (SEM), transmission electron microscopy (TEM), FTIR spectrum, size distribution and zeta potential. Physical and chemical properties were evaluated through measurement of drug release, stability studies, drug loading efficiency (DE) and encapsulation efficiency (EE). Biological activities were evaluated through measurement of MTT assay, lactate dehydrogenase leakage assay (LDH), cell proliferation assays, cell apoptosis analysis, comet assay, wound healing assay, cell invasion and Western blot analysis. Results and Conclusions: The NPs exhibited clear distribution characteristics, improved solubility and stability. BA and C60(OH)n for the NPs displayed a biphasic release pattern with sustained drug release properties. The mixture of C60(OH)n with different hydroxyl groups may have a certain effect on the stability of the NPs system itself. The NPs could effectively inhibit MHCC97H cell proliferation, migration and invasion in vitro. Combined use of C60(OH)n and BA in GBP lipids may improve the inhibit effect of C60(OH)n or BA against HCC cells and reduce cytotoxicity and genotoxicity of C60(OH)n for normal cells. We concluded that one of the important mechanisms of BA-C60(OH)n-GBP-TPGS-NPs inhibiting MHCC97H cells is achieved by up-regulating the expression of Caspase-3, Caspase-8 and Caspase-9.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Fulerenos/farmacocinética , Neoplasias Hepáticas/tratamento farmacológico , Nanopartículas/química , Triterpenos/farmacocinética , Vitamina E/toxicidade , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Fulerenos/administração & dosagem , Fulerenos/química , Humanos , Lipídeos/química , Neoplasias Hepáticas/patologia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanopartículas/administração & dosagem , Triterpenos Pentacíclicos , Poliprenois/química , Triterpenos/administração & dosagem , Vitamina E/química
8.
Molecules ; 25(8)2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32295310

RESUMO

The needles of conifer trees are one of the richest sources of natural polyprenols. Polyprenol homologs from Abies sibirica L. lipophilic 80% purified extract were analyzed and quantified. In total, 10 peaks (Prenol-11 to Prenol-20) were observed in the ultra-high-performance liquid chromatography-diode array detector (UHPLC-DAD) chromatogram of Siberian fir with the most abundant compound being Prenol-15 (relative amount 37.23 + 0.56% of the total polyprenol yield). Abies sibirica L. polyprenol solubility and incorporation efficiency into liposomes were studied in various commercially available lecithin mixtures (Phosal IP40, Phosal 75SA, and Lipoid P45). The resulting multilamellar polyprenol liposomes were morphologically characterized by Light and Transmission Electron Microscopy, and the liposome size was discovered to be polymodal with the main peak at 1360 nm (90% of the volume). As polyprenols are fully soluble only in lipids, a liposomal formulation based upon co-solubilization and a modified ethanol injection method of polyprenols into the ethanol-phospholipid system was developed for the entrapment and delivery of polyprenols for potential commercial applications in food supplement and cosmetic industries.


Assuntos
Abies/química , Lipossomos/análise , Lipossomos/química , Poliprenois/análise , Poliprenois/química , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Peso Molecular , Extratos Vegetais/química , Solventes
9.
Biochemistry ; 59(4): 615-626, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31876413

RESUMO

The protective surfaces of bacteria are comprised of polysaccharides and are involved in host invasion and colonization, host immune system evasion, and antibacterial resistance. A major barrier to our fundamental understanding of these complex surface polysaccharides lies in the tremendous diversity in glycan composition among bacterial species. The polyisoprenoid bactoprenyl phosphate (or undecaprenyl phosphate) is an essential lipid carrier necessary for early stages of glycopolymer assembly. Because of the ubiquity of bactoprenyl phosphate in these critical processes, molecular probes appended to this lipid carrier simplify identification of enzymatic roles during polysaccharide bioassembly. A limited number of these probes exist in the literature or have been assessed with such pathways, and the limits of their use are not currently known. Herein, we devise an efficient method for producing fluorescently modified bactoprenyl probes. We further expand our previous efforts utilizing 2-nitrileaniline and additionally prepare nitrobenzoxadizol-tagged bactoprenyl phosphate for the first time. We then assess the enzyme promiscuity of these two probes utilizing four well-characterized initiating phosphoglycosyltransferases: CPS2E (Streptococcus pneumoniae), WbaP (Salmonella enterica), WecA (Escherichia coli), and WecP (Aeromonas hydrophilia). Both probes serve as substrates for these enzymes and could be readily used to investigate a wide range of bacterial glycoassembly pathways. Interestingly, we have also identified unique solubility requirements for the nitrobenzoxadizol moiety for efficient enzymatic utilization that was not observed for the 2-nitrileaniline.


Assuntos
Proteínas de Bactérias/química , Fosfatos de Poli-Isoprenil/química , Poliprenois/química , Clonagem Molecular/métodos , Escherichia coli/metabolismo , Salmonella enterica/metabolismo , Streptococcus pneumoniae/metabolismo , Açúcares
10.
Arch Biochem Biophys ; 675: 108111, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31563509

RESUMO

Long-chain polyprenol phosphates feature in membrane-associated glycoconjugate biosynthesis pathways across domains of life. These unique amphiphilic molecules are best known as substrates of polytopic membrane proteins, including polyprenol-phosphate phosphoglycosyl and glycosyl transferases, and as components of more complex substrates. The linear polyprenols are constrained by double bond geometry and lend themselves well to interactions with polytopic membrane proteins, in which multiple transmembrane helices form a rich landscape for interactions. Recently, a new superfamily of monotopic phosphoglycosyl transferase enzymes has been identified that interacts with polyprenol phosphate substrates via a single reentrant membrane helix. Intriguingly, despite the dramatic differences in their membrane-interaction domains, both polytopic and monotopic enzymes similarly favor a unique cis/trans geometry in their polyprenol phosphate substrates. Herein, we present a multipronged biochemical and biophysical study of PglC, a monotopic phosphoglycosyl transferase that catalyzes the first membrane-committed step in N-linked glycoprotein biosynthesis in Campylobacter jejuni. We probe the significance of polyprenol phosphate geometry both in mediating substrate binding to PglC and in modulating the local membrane environment. Geometry is found to be important for binding to PglC; a conserved proline residue in the reentrant membrane helix is determined to drive polyprenol phosphate recognition and specificity. Pyrene fluorescence studies show that polyprenol phosphates at physiologically-relevant levels increase the disorder of the local lipid bilayer; however, this effect is confined to polyprenol phosphates with specific isoprene geometries. The molecular insights from this study may shed new light on the interactions of polyprenol phosphates with diverse membrane-associated proteins in glycoconjugate biosynthesis.


Assuntos
Poliprenois/metabolismo , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo , Campylobacter jejuni/crescimento & desenvolvimento , Campylobacter jejuni/metabolismo , Sequência Conservada , Fluidez de Membrana , Lipídeos de Membrana/metabolismo , Ligação Proteica , Conformação Proteica , Especificidade por Substrato , Transferases (Outros Grupos de Fosfato Substituídos)/química
11.
Phytomedicine ; 64: 152927, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31465981

RESUMO

BACKGROUND: Next to aluminum salts, squalene nanoemulsions comprise the most widely employed class of adjuvants in approved vaccines. Despite their importance, the mechanisms of action of squalene nanoemulsions are not completely understood, nor are the structure/function requirements of the oil composition. PURPOSE: In this study, we build on previous work that compared the adjuvant properties of nanoemulsions made with different classes of oil structures to squalene nanoemulsion. Here, we introduce nanoemulsions made with polyprenols derived from species of the Pinaceae family as novel vaccine adjuvant compositions. In contrast with long-chain triglycerides that do not efficiently enhance an immune response, both polyprenols and squalene are comprised of multimeric isoprene units, which may represent an important structural property of oils in nanoemulsions with adjuvant properties. STUDY DESIGN: Oils derived from species of the Pinaceae family were formulated in nanoemulsions, with or without a synthetic Toll-like receptor 4 (TLR4) ligand, and characterized regarding physicochemical and biological activity properties in comparison to squalene nanoemulsions. METHODS: Oils were extracted from species of the Pinaceae family and used to prepare oil-in-water nanoemulsions by microfluidization. Emulsion droplet diameter stability was characterized by dynamic light scattering. Nanoemulsions were evaluated for in vitro biological activity using human whole blood, and in vivo biological activity in mouse, pig, and ferret models when combined with pandemic influenza vaccine antigens. RESULTS: Nanoemulsions comprised of Pinaceae-derived polyprenol oils demonstrated long-term physical stability, stimulated cytokine production from human cells in vitro, and promoted antigen-specific immune responses in various animal models, particularly when formulated with the TLR4 ligand glucopyranosyl lipid adjuvant (GLA). CONCLUSION: Pinaceae-derived nanoemulsions are compatible with inclusion of a synthetic TLR4 ligand and promote antigen-specific immune responses to pandemic influenza antigens in mouse, pig, and ferret models.


Assuntos
Adjuvantes Imunológicos/farmacologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Pinaceae/química , Óleos Vegetais/farmacologia , Poliprenois/farmacologia , Esqualeno/farmacologia , Adjuvantes Imunológicos/química , Animais , Emulsões , Feminino , Furões , Humanos , Influenza Humana/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óleos Vegetais/química , Poliprenois/química , Organismos Livres de Patógenos Específicos , Esqualeno/química , Suínos , Receptor 4 Toll-Like/imunologia
12.
Curr Opin Struct Biol ; 59: 81-90, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31003021

RESUMO

Peripheral and integral membrane proteins feature in stepwise assembly of complex glycans and glycoconjugates. Catalysis on membrane-bound substrates features challenges with substrate solubility and active-site accessibility. However, advantages in enzyme and substrate orientation and control of lateral membrane diffusion provide order to the multistep processes. Recent glycosyltransferase (GT) studies show that substrate diversity is met by the selection of folds which do not converge upon a common mechanism. Examples of polyprenol phosphate phosphoglycosyl transferases (PGTs) highlight that divergent fold families catalyze the same reaction with different mechanisms. Lipid A biosynthesis enzymes illustrate that variations on the robust Rossmann fold allow substrate diversity. Improved understanding of GT and PGT structure and function holds promise for better function prediction and improvement of therapeutic inhibitory ligands.


Assuntos
Membrana Celular/química , Glicoconjugados/química , Sítios de Ligação , Metabolismo dos Carboidratos , Catálise , Domínio Catalítico , Membrana Celular/metabolismo , Celulose/química , Celulose/metabolismo , Glucosiltransferases/química , Glucosiltransferases/metabolismo , Glicoconjugados/biossíntese , Glicosiltransferases/química , Glicosiltransferases/metabolismo , Lipídeo A/biossíntese , Lipídeo A/química , Poliprenois/química , Poliprenois/metabolismo , Polissacarídeos/química , Relação Quantitativa Estrutura-Atividade , Especificidade por Substrato
13.
Rev. odontol. UNESP (Online) ; 48: e20190108, 2019. graf, ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-1099188

RESUMO

Resumo Introdução A quantidade e qualidade óssea na implantodontia é um fator de alta relevância quando se tem por objetivo instalar implantes e reabilitar pacientes. No entanto, essa disponibilidade é comprometida na maioria dos casos, havendo a necessidade da busca de novos biomateriais, membranas e substâncias para uma regeneração mais favorável. Objetivo: O objetivo deste estudo foi avaliar a resposta da neoformação óssea em defeitos críticos em calvárias de ratos utilizando scaffolds de fibras de blenda polimérica a partir de poli (ácido láctico-co-glicólico) e poli-isopreno (Cellprene®). O projeto foi aprovado pelo Comitê de Ética em Experimentação Animal. Material e método Neste estudo, foram utilizados 36 ratos (Rattus Norvegicus), variação albinus, Holtzman, adultos. Os animais foram submetidos à tricotomia na região da calota craniana e à confecção de defeitos ósseos circulares bilaterais com 5 mm de diâmetro. Os animais foram divididos em três grupos: GC - defeito sem colocação de biomaterial; GCol - scaffolds de colágeno (Bio-Gide, da empresa Geistlich Pharma Ag - Biomaterials); GPoli - scaffolds de fibras de blenda polimérica a partir de poli (ácido láctico-co-glicólico - Cellprene®). Cada grupo foi avaliado em quatro períodos experimentais (7, 15, 30 e 60 dias). Após esses períodos, os animais foram sacrificados, e as peças passaram por tramitação laboratorial de rotina e inclusão em parafina. Foram obtidos cortes semisseriados e corados pela técnica de hematoxilina e eosina para análise histométrica e histológica. Foi executada análise histométrica para avaliar a composição do tecido ósseo reparado (% osso). Os dados obtidos foram analisados estatisticamente com nível de significância de 95%. Resultado Foi verificado que o GCol apresentou maior preenchimento do defeito nos períodos de 30 e 60 dias em comparação aos GC e GPoli. Conclusão Os scaffolds de fibras de blenda polimérica a partir de poli (ácido láctico-co-glicólico) e poli-isopreno (Cellprene®) não apresentaram vantagens quando utilizados em defeitos críticos.


Abstract Introduction The bone quantity and quality in implant dentistry is a highly relevant factor when it aims the use of implants and rehabilitation in patients. However, this availability is compromised in most cases, with the need to research new biomaterials, membranes and substances for more favorable regeneration. Objective: The aim of this study was to evaluate the response of bone neoformation in critical defects in rat calvaries using polymeric blend fiber scaffolds from Poly (Lactic-Co-Glycolic Acid) and Polyisoprene (Cellprene®). The project was approved by the Animal Experimentation Ethics Committee. Material and method In this study 36 rats (Rattus Norvegicus), variation albinus, Holtzman, adults were used. The animals had trichotomy in the region of the skull and the confection of bilateral circular bone defects with a diameter of 5 mm. The animals were divided into 3 groups: Group GC - defect without biomaterial placement, Group GCol - collagen scaffolds (Bio-Gide, from Geistlich Pharma Ag - Biomaterials), Group GPoli - polymeric blend fiber scaffolds from Poly (Lactic-Co-Glycolic Acid)-Polyisoprene. Each group was evaluated in 4 experimental periods (7, 15, 30 and 60 days). After these periods the animals were sacrificed and the pieces underwent routine laboratory procedures and paraffin embedding. Semi-serial sections were obtained and stained by hematoxylin and eosin technique for histometric and histological analysis. Histometric analysis was performed to evaluate the composition of repaired bone tissue (% Bone). The data obtained were statistically analyzed with a significance level of 95%. Result It was found that the GCol group presented greater defect filling in the 30 and 60 days periods compared to the GC and GPoli groups. Conclusion Polymer blend fiber scaffolds from Poly (Lactic-Co-Glycolic Acid) and Polyisoprene (Cellprene®) did not have advantages when used in critical defects.


Assuntos
Animais , Ratos , Regeneração Óssea , Substitutos Ósseos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/uso terapêutico , Poliprenois/uso terapêutico
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