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1.
Braz. j. oral sci ; 20: e211512, jan.-dez. 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1254424

ABSTRACT

Aim: Several systemic diseases, such as periodontitis and apical periodontitis, can cause extensive bone resorption. Host defense peptides may have the potential for the development of novel therapies for the bone resorption process. This study evaluated the potential of host defense peptides clavanins A, MO, and LL-37 in in vitro osteoclastogenesis. Methods: RAW 264.7 cultures were stimulated with recombinant of receptor activator of nuclear factor kappa B ligand in the presence of different tested concentrations of host defense peptides, besides calcium hydroxide and doxycycline. Cellular viability, nitric oxide production, and a number of differentiated osteoclast-like cells were also evaluated. Results: Results showed that none of the substances were cytotoxic, except for 128 µg.mL-1 of doxycycline after 3 days. Host defense peptides, calcium hydroxide, and doxycycline did not interfere in nitric oxide production or downregulated it. An exception was observed in the presence of 2 µg.mL-1 of doxycycline, in which nitric oxide production was up-regulated. All host defense peptides were capable of reducing osteoclast-like cell differentiation. Conclusion: Host defense peptides clavanins A and MO demonstrated to be potential suppressors of osteoclastogenesis in vitro without interfering in cellular viability and nitric oxide production. These promising results need to be further analyzed in in vivo models of bone resorption


Subject(s)
Osteogenesis , Bone Resorption , Antimicrobial Cationic Peptides , Nitric Oxide
2.
Braz. j. med. biol. res ; 54(11): e11295, 2021. tab, graf
Article in English | LILACS | ID: biblio-1339451

ABSTRACT

This study aimed to investigate the diagnostic value of heparin-binding protein (HBP) in the cerebrospinal fluid of children with purulent meningitis (PM). This study included 118 children with PM diagnosed at our hospital from January 2018 to January 2020, 110 children with viral meningitis (VM) and 80 children with suspected meningitis who were ruled out by cerebrospinal fluid (CSF) analysis during the same period. HBP and white blood cell (WBC) count in the CSF, and inflammatory factors, including C-reactive protein (CRP), tumor necrosis factor (TNF)-α, and procalcitonin (PCT), were measured. Receiver-operator characteristic curves were used to analyze the predictive value of HBP, CRP, PCT, and TNF-α levels in the diagnosis of PM by CSF analysis. HBP levels in the CSF of children with PM were higher, while the CRP and serum PCT and TNF-α levels were elevated in all groups (P<0.05). In addition, HBP levels in the CSF were more accurate for the diagnosis of PM than traditional diagnostic indexes. HBP levels in the CSF can be used as an important reference for early diagnosis of PM.


Subject(s)
Humans , Child , Meningitis, Bacterial/diagnosis , Meningitis, Viral , C-Reactive Protein , Blood Proteins , Antimicrobial Cationic Peptides , Procalcitonin
3.
Chinese Journal of Biotechnology ; (12): 1277-1282, 2020.
Article in Chinese | WPRIM | ID: wpr-826849

ABSTRACT

Microbial biofilm, a consortium of microbial cells protected by a self-produced polymer matrix, is considered as one main cause of current bacterial drug resistance. As a new type of antimicrobial agents, antimicrobial peptides provide a new strategy for the treatment of antibiotic resistant bacteria biofilm infections. Antimicrobial peptides have shown unique advantages in preventing microbial colonization of surfaces, killing bacteria in biofilms or disrupting the mature biofilm structure. This review systemically analyzes published data in the recent 30 years to summarize the possible anti-biofilm mechanisms of antimicrobial peptides. We hope that this review can provide reference for the treatment of infectious diseases by pathogenic microbial biofilm.


Subject(s)
Anti-Bacterial Agents , Pharmacology , Antimicrobial Cationic Peptides , Pharmacology , Bacteria , Biofilms , Drug Resistance, Bacterial , Microbial Sensitivity Tests , Research
4.
Adv Rheumatol ; 60: 54, 2020. tab
Article in English | LILACS | ID: biblio-1152730

ABSTRACT

Abstract Background: Systemic sclerosis (SSc) is an autoimmune disease characterized by fibrosis of skin and lung as well as involvement of kidney, gastrointestinal system and heart. Aetiology and exact mechanism of disease is poorly understood. The association between antimicrobial peptides (AMPs) and other diseases such as idiopathic pulmonary fibrosis, diffuse panbronchiolitis, pulmoner alveolar proteinosis and psoriasis have been reported. A small number of studies have examined the role of AMPs on autoimmune diseases which has not been studied in scleroderma yet. We aimed to investigate AMP serum levels and their association with disease characteristics of SSc. Methods: Forty-two patients (40 female, mean age 42 years) and 38 healthy subjects (32 female, mean age 38 years) were enrolled. For SSc patients, the following data were recorded: disease subset (limited/diffuse), autoantibodies (antinuclear, anti-centromere (ACA), and anti-SCL-70), blood tests, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP), modified Rodnan skin score, presence and history of digital ulcers, kidney, gastrointestinal disease and lung involvement assessed by computed tomography and pulmonary function tests. Association between serum AMPs and disease characteristics were analysed. Results: Twenty-nine of the patients had diffuse (69%) and 13 of the patients had limited (31%) systemic sclerosis. Average disease duration was 5.5 years. Pulmonary involvement was detected in 20 patients (47.6%). Serum concentration of alpha defensin was higher than healthy subjects (563 ± 415 vs 377 ± 269 ng/mL, p = 0.02). However, no difference was observed for beta-1 and beta-2 defensins in SSc patients and healthy controls. In sub-group analysis patients with interstitial lung disease had higher levels of alpha defensin than those without lung involvement (684 ± 473 vs 430 ± 299 ng/ml, p = 0.04). There was also correlation between alfa defensin serum concentrations and CRP (r = 0.34). Conclusions: Alpha defensin levels are increased in scleroderma patients and correlated with lung involvement indicating a role in the pathogenesis of disease. Trial registration: This study is not a clinical trial study.(AU)


Subject(s)
Humans , Scleroderma, Systemic/pathology , Antimicrobial Cationic Peptides/blood , alpha-Defensins/blood , beta-Defensins/blood , Lung Diseases/etiology
5.
Rev. cuba. med. trop ; 71(2): e343, mayo.-ago. 2019. tab, graf
Article in English | LILACS, CUMED | ID: biblio-1093562

ABSTRACT

Antimicrobial peptides are small cationic molecules present in almost all living organisms. They show direct or indirect (immunomodulation) activity in a wide range of pathogenic microorganisms as members of the humoral arsenal of innate immunity. In mammals they play a significant role in respiratory airways. The most abundant antimicrobial peptides in the respiratory tract of mammals are lysozymes, lactoferrin, histatins, defensins and cathelicidins. Respiratory and pulmonary infections are combated, primarily, by antimicrobial peptides like LL-37 against Gram-negative bacteria, histatin 5 against Candida albicans and human peptides from neutrophils against adenovirus, influenza and parainfluenza. This paper provides a review of the most important antimicrobial peptides in the respiratory tract and their use in the search for new effective agents against microorganisms that cause respiratory infections based on information published in MedLine, the Web of Science and Scopus in recent years(AU)


Los péptidos antimicrobianos son pequeñas moléculas catiónicas presentes en casi todos los organismos vivos. Muestran actividad directa o indirecta (inmunomodulación) en una amplia gama de microorganismos patógenos como miembros del arsenal humoral de la inmunidad innata. En los mamíferos juegan un papel importante en las vías respiratorias. Los péptidos antimicrobianos más abundantes en el tracto respiratorio son lisozima, lactoferrina, histatinas, defensinas y catelicidinas. Las infecciones respiratorias y pulmonares son combatidas, principalmente, por péptidos antimicrobianos como LL-37 contra bacterias gramnegativas, histatina 5 contra Candida albicans y péptidos humanos de neutrófilos contra adenovirus, influenza y parainfluenza. Este artículo proporciona una revisión sobre los péptidos antimicrobianos más importantes en el tracto respiratorio y su empleo en la búsqueda de nuevos agentes eficaces contra microorganismos causantes de infecciones respiratorias teniendo en cuenta la información publicada al respecto en MedLine, Web of Science y Scopus en los últimos años(AU)


Subject(s)
Humans , Drug Resistance, Microbial , Paramyxoviridae Infections , Antimicrobial Cationic Peptides/therapeutic use
6.
Article in English | WPRIM | ID: wpr-758901

ABSTRACT

The recent emergence of Staphylococcus schleiferi in dogs with otitis externa or skin and soft tissue infections has become a significant zoonotic issues. In the current study, we investigated 1) the carriage rates of S. schleiferi among major staphylococci in healthy dogs and dogs with otitis externa, 2) antibiotic susceptibility profiles of S. schleiferi, particularly methicillin resistance (MR), and 3) virulence factors associated with skin and soft tissue infections such as ability to form biofilm, resistance to cationic antimicrobial peptides (CAMPs), and carriage of staphylococcal enterotoxin genes. Among the 21 S. schleiferi isolates, 5 isolates (24%) were determined to be methicillin-resistant (MRSS). Staphylococcal cassette chromosome mec (SCCmec) typing revealed the presence of SCCmec type V in 4 MRSS isolates and type VII in one MRSS. Higher levels of antibiotic resistance, especially multidrug resistance, were observed in MRSS isolates compared to the methicillin-susceptible S. schleiferi (MSSS) isolates. In addition, MRSS isolates exhibited enhanced ability to form biofilm under static condition and all the 5 MRSS isolates carried three or more enterotoxin genes. However, there were no significant differences in resistance to CAMPs between MRSS and MSSS isolates. These findings suggest that coagulase-negative S. schleiferi is becoming more prevalent in canine otitis externa cases. Our results also highlight the presence of multidrug-resistant MRSS isolates with enhanced biofilm production and carriage of multiple enterotoxins.


Subject(s)
Animals , Antimicrobial Cationic Peptides , Biofilms , Dogs , Drug Resistance, Microbial , Drug Resistance, Multiple , Enterotoxins , Methicillin Resistance , Otitis Externa , Otitis , Skin , Soft Tissue Infections , Staphylococcus , Virulence Factors , Virulence
7.
Article in Chinese | WPRIM | ID: wpr-775896

ABSTRACT

OBJECTIVE@#To explore the objectivity and time-effect of stimulating effect at acupoint with PGLA in the healthy person, and to provide a basis for the rational interval of minimally invasive embedding of PGLA.@*METHODS@#Before embedding, 8 h, 3rd, 7th, 10th, 14th day after embedding, medical imaging magnetic resonance imaging (MRI) scanning technique was used to collect local T2WI pressure-lowering and T2-Mapping 8 echoes sequence image of left Zusanli (ST 36) in 8 cases of healthy person. The T2-Mapping 8 echoes sequence image was generated by the relevant software to the T2-Mapping image and the local T2 value was measured. The characteristics of local T2WI pressure-fat image signal intensity and the change of T2 value at left Zusanli (ST 36) with minimally invasive embedding with PGLA were observed and analyzed.@*RESULTS@#①There was no abnormal signal on the T2WI pressure-fat image on the left Zusanli (ST 36) point before the embedding. The high-signal was seen on the local T2WI pressure-fat image at each time point after embedding, there was no significant difference in local signal intensity between 8 h, 3rd and 7th day after embedding. The local signal intensity decreased on the 10th day after embedding, and the local signal intensity decreased significantly on the 14th day after embedding.②The T2 value at each time point after embedding increased significantly compared with that before embedding (all 0.05); there was no significant difference between the T2 value on the 7th and the 10th day after embedding (>0.05),the T2 value on the 14th day after embedding was significantly lower than that on the 7th day after embedding (<0.01).@*CONCLUSION@#It has a stimulating effect on the local acupoints with minimally invasive embedding with PGLA in the healthy person, and the stimulating effect has certain time-effect. The effective stimulation time is about 2 weeks. The rational interval period for the minimally invasive embedding with the PGLA of the same specification type should be about 2 weeks.


Subject(s)
Acupuncture Points , Antimicrobial Cationic Peptides , Magnetic Resonance Imaging
8.
Chinese Medical Journal ; (24): 569-576, 2019.
Article in English | WPRIM | ID: wpr-774811

ABSTRACT

BACKGROUND@#Glucocorticoids have been widely used to treat patients with chronic obstructive pulmonary disease (COPD). Nevertheless, corticosteroid insensitivity is a major barrier to the effective treatment of COPD and its mechanism remains unclear. This study aimed to evaluate the effect of cathelicidin LL-37 on corticosteroid insensitivity in COPD rat model, and to explore the involved mechanisms.@*METHODS@#COPD model was established by exposing male Wistar rats to cigarette smoke combined with intratracheal instillation of lipopolysaccharide (LPS). Inhaled budesonide and LL-37 were consequently applied to COPD models separately or collectively to confirm the effects on inflammatory cytokines (tumor necrosis factor [TNF]-α and transforming growth factor [TGF]-β) by enzyme-linked immunosorbent assay (ELISA) and lung tissue histopathological morphology. Expression of histone deacetylase-2 (HDAC2) and phosphorylation of Akt (p-AKT) in lung were also measured.@*RESULTS@#Briefly, COPD model rats showed an increased basal release of inflammatory cytokines (lung TNF-α: 45.7 ± 6.1 vs. 20.1 ± 3.8 pg/mL, P < 0.01; serum TNF-α: 8.9 ± 1.2 vs. 6.7 ± 0.5 pg/mL, P = 0.01; lung TGF-β: 122.4 ± 20.8 vs. 81.9 ± 10.8 pg/mL, P < 0.01; serum TGF-β: 38.9 ± 8.5 vs. 20.6 ± 2.3 pg/mL, P < 0.01) and COPD related lung tissue histopathological changes, as well as corticosteroid resistance molecular profile characterized by an increase in phosphoinositide 3-kinase (PI3K)/Akt (0.5 ± 0.1 fold of control vs. 0.2 ± 0.1 fold of control, P = 0.04) and a decrease in HDAC2 expression and activity (expression: 13.1 ± 0.4 μmol/μg vs. 17.4 ± 1.1 μmol/μg, P < 0.01; activity: 1.1 ± 0.1 unit vs. 1.4 ± 0.1 unit, P < 0.01), compared with control group. In addition, LL-37 enhanced the anti-inflammatory effect of budesonide in an additive manner. Treatment with combination of inhaled corticosteroids (ICS) and LL-37 led to a significant increase of HDAC2 expression and activity (expression: 15.7 ± 0.4 μmol/μg vs. 14.1 ± 0.9 μmol/μg, P < 0.01; activity: 1.3 ± 0.1 unit vs. 1.0 ± 0.1 unit, P < 0.01), along with decrease of p-AKT compared to budesonide monotherapy (0.1 ± 0.0 fold of control vs. 0.3 ± 0.1 fold of control, P < 0.01).@*CONCLUSIONS@#This study suggested that LL-37 could improve the anti-inflammatory activity of budesonide in cigarette smoke and LPS-induced COPD rat model by enhancing the expression and activity of HDAC2. The mechanism of this function of LL-37 might involve the inhibition of PI3K/Akt pathway.


Subject(s)
Animals , Antimicrobial Cationic Peptides , Pharmacology , Therapeutic Uses , Glucocorticoids , Metabolism , Histone Deacetylase 2 , Metabolism , Humans , Inflammation , Drug Therapy , Lipopolysaccharides , Pharmacology , Male , Phosphatidylinositol 3-Kinases , Metabolism , Proto-Oncogene Proteins c-akt , Metabolism , Pulmonary Disease, Chronic Obstructive , Drug Therapy , Metabolism , Rats , Rats, Wistar , Smoking , Tumor Necrosis Factor-alpha , Metabolism
9.
Article in Chinese | WPRIM | ID: wpr-771397

ABSTRACT

Defensins are endogenous cationic antimicrobial peptides rich in arginine and cysteine residues. They are important immune factors resisting pathogenic bacteria infection for mollusks. The 43 amino acid residues near the carboxyl terminal for Crassostrea gigas defensin (CgD) form its mature peptide region, responsible for the biological activity of CgD. First, two target genes, CgDH⁺ (with 6×His-tag at 3' end) and CgDH- (without 6×His-tag at 3' end) were separated and amplified by RT-PCR with specific primers from Crassostrea gigas mantle. These two target genes were ligated to the expression vector pPICZαA to construct recombinant expression vectors, pPICZαA-CgDH⁺ and pPICZαA-CgDH-, which were transformed into competent Pichia pastoris X-33 cells by electroporation respectively. The recombinant target proteins, CgDH⁺ and CgDH-, were induced for 72 h with 1% methanol at 29 °C and 250 r/min. The recombinant CgDH⁺ (5.78 kDa) was purified by immobilized metal affinity chromatography (IMAC), and identified by MALDI-TOF-TOF analysis, demonstrating that it was the expected target protein. Based on the concentration of the purified product, the estimated yield of recombinant CgDH⁺ was 2.32 mg/L. Antimicrobial assay showed that the culture medium supernatant containing recombinant CgDH⁺ and recombinant CgDH-, respectively, had activities against Staphylococcus aureus and Pseudomonas aeruginosa, indicating that the existence of 6×His tag in the recombinant proteins do not affect their biological activities.


Subject(s)
Animals , Anti-Bacterial Agents , Antimicrobial Cationic Peptides , Crassostrea , Defensins , Pichia , Recombinant Proteins
10.
J. bras. pneumol ; 45(4): e20190001, 2019. tab, graf
Article in Portuguese | LILACS | ID: biblio-1019982

ABSTRACT

RESUMO Objetivo Este estudo teve como objetivo determinar os níveis séricos de proteína 3 contendo um domínio NACHT, porção C-terminal rica em repetições de leucina e de domínio pirina (NLRP3) e catelicidina LL-37, bem como investigar sua importância prognóstica em pneumonia adquirida na comunidade (PAC). Métodos Este estudo prospectivo incluiu 76 pacientes com PAC. Foram obtidos dados demográficos e características clínicas. Os níveis séricos de NLRP3 e LL-37 foram determinados por meio do teste ELISA. A correlação entre NLRP3 e LL-37 foi estimada por intermédio da análise de Spearman. A associação entre NLRP3 e LL-37 com 30 dias de taxa de sobrevida e de mortalidade foi avaliada pela curva de Kaplan-Meier e análise de regressão logística. Resultados Os níveis séricos de NLRP3 estavam elevados, enquanto os níveis de LL-37 apresentaram redução significativa em pacientes com PAC grave. Observou-se correlação significativa entre os níveis séricos de NLRP3 e LL-37 em pacientes com PAC. Pacientes com níveis elevados de NLRP3 e níveis reduzidos de LL-37 exibiram maior taxa de sobrevida em 30 dias e de mortalidade quando comparados com aqueles com níveis inferiores de NLRP3 e LL-37. Conclusões Pacientes com PAC grave tendem a apresentar níveis séricos elevados de NLRP3 e níveis reduzidos de LL-37, o que pode ser utilizado como um potencial biomarcador prognóstico.


ABSTRACT Objective This study aimed to determine the serum levels of NACHT, Leucine-rich repeat (LRR), and Pyrin (PYD) domains-containing Protein 3 (NLRP3) and cathelicidin LL-37, and investigate their prognostic significance in community-acquired pneumonia (CAP). Methods The sample of this prospective study was composed of 76 consecutive patients with CAP. Demographic data and clinical characteristics were collected. Serum levels of NLRP3 and LL-37 were determined by ELISA. Spearman's analysis was used to evaluate the correlation between NLRP3 and LL-37. Association of NLRP3 and LL-37 with 30-day survival and mortality rates was assessed using the Kaplan-Meier curve and logistic regression analysis. Results Serum NLRP3 significantly increased whereas serum LL-37 significantly decreased in patients with severe CAP. Significant correlation was observed between serum NLRP3 and LL-37 in CAP patients. Patients with higher levels of NLRP3 and lower levels of LL-37 showed lower 30-day survival rate and higher mortality compared with those with lower NLRP3 and higher LL-37 levels. Conclusion Severe CAP patients tend to present higher serum NLRP3 and lower serum LL-37, which might serve as potential biomarkers for CAP prognosis.


Subject(s)
Humans , Male , Female , Middle Aged , Aged , Pneumonia/blood , Proteins/analysis , Community-Acquired Infections/blood , Antimicrobial Cationic Peptides/blood , NLR Family, Pyrin Domain-Containing 3 Protein/blood , Pyrin/blood , Pneumonia/mortality , Biomarkers/blood , Case-Control Studies , Logistic Models , Multivariate Analysis , Predictive Value of Tests , Prospective Studies , Community-Acquired Infections/mortality , Kaplan-Meier Estimate
11.
Araçatuba; s.n; 2019. 114 p. tab, graf, ilus.
Thesis in English, Portuguese | LILACS, BBO | ID: biblio-1051133

ABSTRACT

Este trabalho foi dividido em dois capítulos que objetivou avaliar: 1) o efeito isolado ou combinado do flavonoide epigallocatechin-3-gallate (EGCG) em associação com o peptídeo LL-37 e seu análogo KR-12-a5 sobre a viabilidade celular de fibroblastos e sobre cultura planctônica, biofilme simples, dual-espécies e túbulos dentináios e 2) as interações sinérgicas do EGCG e proantocianidina do oxicoco (A-type cranberry proanthocyanidins, AC-PAC), quando usado em combinação com LL-37 ou KR-12-a5 sobre a viabilidade celular, a capacidade de migração e inibição das citocinas em cultura de fibroblastos (HGF-1), quando estimuladas ou não pelo lipopolissacarídeo de A. actinomycetencomitans (LPS). No capítulo 1, a concentração inibitória mínima (MIC), a concentração bactericida mínima (MBC) e concentração inibitória fracionária (FIC) de EGCG, LL-37 e KR-12-a5 foram determinadas a partir de valores decrescentes dos compostos por meio dos métodos de microdiluição e checkerboard contra Streptococcus mutans, Enterococcus faecalis, Actinomyces israelii e Fusobacterium nucleatum após 24 horas de tratamento. Fibroblastos da linhagem L-929 foram expostos a combinações de EGCG com peptídeos em diferentes concentrações e o metabolismo celular avaliado por ensaios de MTT. Os compostos com melhor efeito antimicrobiano e citotóxico foram avaliados por 24-36h, isoladamente ou em combinação, em biofilmes individuais ou biofilmes de dual-espécies com E. faecalis formados em placas de poliestireno por 48h por meio de contagem bacteriana. Os biofilmes de E. faecalis também foram cultivados em túbulos dentinários por 2 semanas, tratados com EGCG, KR-12-a5 e EGCG + KR-12-a5 e a porcentagem de células mortas foi determinada pela análise de imagens usando Microscopia Confocal. No capítulo 2, a linhagem celular de fibroblastos gengivais humanos primários HGF-1 foi pré-tratada durante 2 h com EGCG ou AC-PAC a 25 e 12,5 µg / mL, LL-37 ou KR-12-a5 a 0,06 e 0,03 µM ou com uma combinação de EGCG + ACPAC; AC-PAC + KR-12-a5; AC-PAC + LL-37; EGCG + KR-12-a5 ou EGCG + LL-37, nas mesmas concentrações. As culturas celulares foram então estimuladas com 50 µg/mL de LPS por 24-48h. A viabilidade celular e migração foram analisadas usando ensaios colorimétricos e fluorescentes, respectivamente. A quantificação de citocinas foi determinada por ensaios multiplex ELISA. Os resultados mostraram que em condições planctônicas, EGCG + KR-12-a5 apresentaram efeito sinérgico ou aditivo contra todas as bactérias testadas, com FIC menor que os valores de MIC obtidos pelos compostos isolados. As combinações de EGCG e peptídeos testados não foram tóxicas para os fibroblastos, uma vez que o crescimento celular foi superior a 70%. Em condições de biofilme simples, EGCG + KR-12-a5 eliminou S. mutans e A. israelii e reduziu E. faecalis e F. nucleatum. Para biofilmes de duas espécies, quando E. faecalis foi combinado com S. mutans, EGCG + KR-12-a5 teve efeito sinérgico eliminando S. mutans e reduzindo estatisticamente as contagens de E. faecalis. Em biofilmes associando E. faecalis e A. israelii ou F. nucleatum, EGCG + KR-12-a5 eliminaram E. faecalis e promoveram redução de A. israelii e F. nucleatum, embora não tenha sido observada diferença estatística entre os compostos. EGCG + KR-12-a5 reduziu mais de 80% dos biofilmes de E. faecalis nos túbulos dentinários. Dentre os grupos experimentais estudados, o EGCG, principalmente a 25 e 12,5 µg/mL estimulou o crescimento de fibroblastos, protegendo-os dos efeitos do LPS. Efeito sinérgico entre EGCG + AC-PAC, EGCG + LL-37 e EGCG + KR-12-a5 no metabolismo celular também foi observado na presença de LPS. Combinações do EGCG com AC-PAC ou KR-12-a5 e AC-PAC com LL-37 foram capazes de aumentar estatisticamente a migração celular. EGCG, AC-PAC, LL-37 e KR-12-a5 promoveram a redução de citocinas individualmente ou em combinação (EGCG + AC-PAC e EGCG + KR12-a5) mais especificamente para IL-6, IL-8, GM- CSF e TNF-α. Conclui-se que a associação de EGCG e KR-12-a5 é citocompatível e promove um efeito sinérgico contra bactérias associadas a infecções endodônticas, sob condições planctônicas e de biofilme. O EGCG, isoladamente ou associado ao AC-PAC e ao KR-12-a5, aumenta a viabilidade e migração celular, bem como a inibição de citocinas por fibroblastos estimulados por LPS. A associação de EGCG com KR-12-a5 poderia ser uma opção de princípio ativo em medicações para fins endodônticos(AU)


This study was divided in two chapters that aimed to evaluate: 1) the effect of flavonoid epigallocatechin-3-gallate (EGCG), cationic peptide LL-37 peptide and its analogue KR12-a5, alone or in combination, on fibroblast cell viability and on bacteria in planktonic and single/dual-species biofilms/dentin tubules; 2) the synergistic interactions of EGCG and cranberry proanthocyanidins (A-type cranberry proanthocyanidins, AC-PAC), when used in combination with LL-37 or KR-12-a5 on cell viability, the ability to induce cell migration and inhibit cytokines in culture of fibroblasts (HGF-1) when stimulated or not by the lipopolysaccharide of A. actinomycetencomitans (LPS). For the chapter 1, Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and fractional inhibitory concentration (FIC) of EGCG, LL-37 and KR-12-a5 were determined from decreasing values of the compounds by Streptococcus mutans, Enterococcus faecalis, Actinomyces israelii and Fusobacterium nucleatum against microdilution and checkerboard after 24 hours of treatment. L-929 fibroblasts were exposed to combinations of EGCG with peptides at different concentrations and cell metabolism assessed by MTT assays. The compounds if the best antimicrobial and cytotoxic effect were also evaluated for 24-36h, alone or in combination, in 48h singleor dual-species biofilms with E. faecalis formed on polystyrene plates by bacterial counting. E. faecalis biofilms were also cultured in dentin tubules for 2 weeks and treated with EGCG, KR-12-a5 and EGCG + KR-12-a5 to determine the percentage of dead cells by analysis of images using Confocal Microscopy. For the chaper 2, primary human gingival fibroblast HGF-1 cell line was pretreated for 2 h with either EGCG or AC-PAC at 25 and 12.5 µg/mL, LL-37 or KR-12-a5 at 0.03 and 0.06 µM or with a combination of EGCG + AC-PAC; AC-PAC + KR-12-a5; AC-PAC + LL-37; EGCG + KR-12-a5 or EGCG + LL37, at the same concentrations. Cell cultures were then stimulated with 50 µg/mL LPS for 24-48h. Cell viability and migration were analyzed using colorimetric and fluorescent assays, respectively. Quantification of cytokines was determined by multiplex ELISA assays. The results show that in planktonic conditions, EGCG + KR-12- a5 showed a synergistic or additive effect against all the bacteria tested, with FIC lower than the MIC values obtained by the compounds alone. Combinations of EGCG and peptides tested were not toxic to fibroblasts, since cell growth was higher than 70%. Under single biofilm conditions, EGCG + KR-12-a5 eliminated S. mutans and A. israelii and reduced E. faecalis and F. nucleatum. For dual- species biofilms, when E. faecalis was combined with S. mutans, EGCG + KR-12-a5 had a synergistic effect by eliminating S. mutans and statistically reducing E. faecalis counts. In biofilms associated with E. faecalis and A. israelii or F. nucleatum, EGCG + KR-12-a5 eliminated E. faecalis and promoted reduction of A. israelii and F. nucleatum, although no statistical difference was observed between the compounds. EGCG + KR-12-a5 reduced more than 80% of the E. faecalis biofilms in the dentin tubules. Among the experimental groups studied, EGCG, mainly at 25 and 12.5 µg/mL stimulated the growth of fibroblasts, protecting them from the effects of LPS. Synergistic effect between EGCG + AC-PAC, EGCG + LL-37 and EGCG + KR12-a5 on cell metabolism was also observed in the presence of LPS. Combinations of EGCG with AC-PAC or KR-12-a5 and AC-PAC with LL-37 were able to increase statistically cell migration. EGCG, AC-PAC, LL-37 and KR-12-α5 promoted cytokine reduction individually or in combination (EGCG + AC-PAC and EGCG + KR-12-a5) more specifically for IL-6, IL-8, GM-CSF and TNF-α. The association of EGCG and KR-12-a5 was cytocompatible and promoted a synergistic effect against bacteria associated with endodontic infections under planktonic and biofilm conditions. EGCG, alone or in combination with AC-PAC and KR-12-a5, increases cell viability and migration, as well as inhibition of cytokines by LPS-stimulated fibroblasts. The association of EGCG with KR12-a5 could be an option as active principle for medications to be used for endodontic purposes(AU)


Subject(s)
Flavonoids , Biofilms , Antimicrobial Cationic Peptides , Cytokines , Fibroblasts
12.
Rev. Soc. Bras. Med. Trop ; 52: e20190133, 2019. tab, graf
Article in English | LILACS | ID: biblio-1020438

ABSTRACT

Abstract INTRODUCTION: Chagas disease (CD) is an important public health problem in Brazil and worldwide. Aging and obesity are important matters in patients with CD, as is hypovitaminosis D3, which can decrease the quality of life of these patients. Immunomodulation mediated by vitamin D3, especially the production of antimicrobial peptides such as cathelicidin LL-37, might be related to the severity and symptoms of CD. This study aimed to determine the serum levels of vitamin D and LL-37 and VDR gene polymorphisms in patients with chronic CD. METHODS: This study included male patients with cardiac and indeterminate clinical forms of CD. Clinical, anthropometric, and blood parameters were obtained. Serum levels of 25(OH)D3 and LL-37 were determined by chemiluminescence and enzyme-linked immunosorbent assay respectively. Fok (rs731236), Bsm (rs1544410), Apa (rs7975232), and Taq (rs731236) polymorphisms of the VDR gene were investigated by PCR-RFLP. RESULTS: Sixty-four patients were included in the study: 18 of the cardiac form and 46 of the indeterminate form. No differences in age, ethnicity, BMI, arterial hypertension, diabetes mellitus, or dyslipidemias were observed between groups. However, the serum levels of 25(OH)D3, but not of LL-37, were lower in the cardiac form group. The association among polymorphisms, vitamin D, and clinical form was not significant. CONCLUSIONS: Decreased levels of vitamin D suggest an association with the cardiac form of CD. Studies investigating the roles of vitamin D and LL-37 in the immune response and their associations with VDR polymorphisms and disease susceptibility are necessary.


Subject(s)
Humans , Male , Polymorphism, Genetic/genetics , Chagas Disease/genetics , Chagas Disease/blood , Receptors, Calcitriol/genetics , Cholecalciferol/blood , Antimicrobial Cationic Peptides/blood , Biomarkers/blood , Middle Aged
13.
ImplantNewsPerio ; 3(2): 324-334, mar.-abr. 2018. ilus, tab
Article in Portuguese | LILACS, BBO | ID: biblio-883519

ABSTRACT

Objetivo: realizar um levantamento sistemático da literatura no que tange ao uso de peptídeos antimicrobianos contra periodontopatógenos e indicar quais os peptídeos e micro-organismos mais estudados, com o objetivo final de traçar um perfil das publicações na área. Material e métodos: a busca por artigos ocorreu na base de dados Pubmed, com os seguintes critérios de inclusão: publicação nos últimos dez anos; palavras-chave "Antimicrobial Peptide" and "Periodontal" and "Bacteria", publicados em inglês e disponíveis gratuitamente na íntegra para leitura. Um total de dez artigos foram selecionados após o refinamento dos dados. Resultados: apesar do pequeno número de estudos encontrados, evidencia-se o potencial uso de peptídeos antimicrobianos no controle das principais bactérias periodontopatogênicas. Além disso, os peptídeos produzidos por células da mucosa oral (Defensinas, LL-37 e Histatinas), bem como os micro-organismos Porphyromonas gingivalis e Fusobacterium nucleatum, foram os mais estudados. Conclusão: é possível concluir que o uso de peptídeos antimicrobianos como potencial ferramenta no controle microbiano tem uma importância crescente, provavelmente devido à sua ampla aplicabilidade, mecanismos de ação e baixos índices de resistência. Contudo, estudos relacionados à sua toxicidade sobre células humanas, modo de aplicação e ensaios clínicos precisam ser realizados.


Objectives: to perform a systematic review of the literature regarding the use of antimicrobial peptides against periodontopathogens and indicate the most studied peptides and microorganisms, with the final objective of outlining a profile of publications in the area. Material and methods: the search for articles occurred in Pubmed database with the following inclusion criteria: publication in the last 10 years; Keywords "Antimicrobial Peptide" and "Periodontal" and "Bacteria", published in English and freely available for reading. Results: a total of 10 articles were selected after refi ning the data. Despite the small number of studies found, it is evident the potential use of antimicrobial peptides in the control of the main periodontopathogenic bacteria. In addition, the peptides produced by oral mucosa cells (Defensins, LL-37 and Histatins) as well as the microorganisms Porphyromonas gingivalis and Fusobacterium nucleatum were the most studied. Conclusion: it is possible to conclude that the use of antimicrobial peptides as a tool in microbial control is of increasing importance, probably due to their wide applicability, mechanisms of action and low resistance indices. However, studies related to its toxicity on human cells, mode of application and clinical trials still need to be performed.


Subject(s)
Antimicrobial Cationic Peptides , Antimicrobial Cationic Peptides/therapeutic use , Biofilms/growth & development , Periodontal Diseases
14.
Braz. j. microbiol ; 49(supl.1): 213-219, 2018. tab, graf
Article in English | LILACS | ID: biblio-974341

ABSTRACT

ABSTRACT Background: Cerebrospinal fluid bacterial culture is the gold-standard for confirmation of acute bacterial meningitis, but many cases are not culture confirmed. Antibiotics reduce the chance of a microbiological diagnosis. Objective to evaluate efficacy of Heparin-binding protein in diagnosis of bacterial meningitis. Patients: 30 patients diagnosed with acute bacterial meningitis, 30 viral meningitis, and 30 subjects with normal CSF findings. Design: Diagnosis was based on history, clinical criteria, CSF examination, latex agglutination & culture, and sensitivities and response to therapy. HBP was measured using enzyme-linked immunosorbent technique in both serum & CSF. Results: Cerebrospinal fluid HBP levels averaged 0.82 ± 0.3 ng/mL in controls, 3.3 ± 1.7 ng/mL in viral and 174.8 ± 46.7 ng/mL in bacterial meningitis. Mean serum level was 0.84 ± 0.3 ng/mL in the controls, 3.7 ± 1.9 ng/mL in viral, and 192.2 ± 56.6 ng/mL in bacterial meningitis. Both HBP levels were significantly higher in patients with bacterial meningitis. Cut-offs of 56.7 ng/ml and 45.3 ng/ml in cerebrospinal fluid & serum showed 100% overall accuracy. Even in patients who received prior antibiotics, remained elevated. Conclusion: Serum Heparin-binding protein serves as a non-invasive potential marker of acute bacterial meningitis even in partially treated cases.


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Young Adult , Blood Proteins/cerebrospinal fluid , Heparin/metabolism , Carrier Proteins/cerebrospinal fluid , Carrier Proteins/blood , Meningitis, Bacterial/diagnosis , Antimicrobial Cationic Peptides/cerebrospinal fluid , Antimicrobial Cationic Peptides/blood , Biomarkers/cerebrospinal fluid , Biomarkers/blood , Cross-Sectional Studies , Meningitis, Bacterial/cerebrospinal fluid , Meningitis, Bacterial/microbiology , Meningitis, Bacterial/blood , Middle Aged
15.
Braz. j. microbiol ; 48(4): 809-814, Oct.-Dec. 2017. graf
Article in English | LILACS | ID: biblio-889176

ABSTRACT

ABSTRACT This study aimed to describe a Bacillus subtilis expression system based on genetically modified B. subtilis. Abaecin, an antimicrobial peptide obtained from Apis mellifera, can enhance the effect of pore-forming peptides from other species on the inhibition of bacterial growth. For the exogenous expression, the abaecin gene was fused with a tobacco etch virus protease cleavage site, a promoter Pglv, and a mature beta-glucanase signal peptide. Also, a B. subtilis expression system was constructed. The recombinant abaecin gene was expressed and purified as a recombinant protein in the culture supernatant. The purified abaecin did not inhibit the growth of Escherichia coli strain K88. Cecropin A and hymenoptaecin exhibited potent bactericidal activities at concentrations of 1 and 1.5 µM. Combinatorial assays revealed that cecropin A and hymenoptaecin had sublethal concentrations of 0.3 and 0.5 µM. This potentiating functional interaction represents a promising therapeutic strategy. It provides an opportunity to address the rising threat of multidrug-resistant pathogens that are recalcitrant to conventional antibiotics.


Subject(s)
Antimicrobial Cationic Peptides/genetics , Antimicrobial Cationic Peptides/metabolism , Bacillus subtilis/genetics , Genetic Vectors/genetics , Insect Proteins/genetics , Insect Proteins/metabolism , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology , Antimicrobial Cationic Peptides/isolation & purification , Antimicrobial Cationic Peptides/pharmacology , Bacillus subtilis/metabolism , Escherichia coli/drug effects , Escherichia coli/growth & development , Gene Expression , Genetic Vectors/metabolism , Insect Proteins/isolation & purification , Insect Proteins/pharmacology , Protein Engineering , Protein Transport , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Recombinant Proteins/pharmacology
16.
Arq. bras. oftalmol ; 80(5): 277-280, Sept.-Oct. 2017. tab, graf
Article in English | LILACS | ID: biblio-888148

ABSTRACT

ABSTRACT Purpose: To investigate human beta-defensins (HBDs) and cathelicidin LL-37 (LL-37) expressions in patients with pterygium. Methods: In this retrospective consecutive case series, 26 pterygium specimens and 15 normal conjunctival specimens of 15 control subjects were in vestigated. Expressions of HBD-1, HBD-2, HBD-3, and LL-37 were assessed using immuno histochemical staining. A brown color in the cytoplasm and/or nuclei of epithelial cells indicated positive staining for HBDs and LL-37. For each antibody, the intensity of the reaction (negative [-], weak [1+], moderate [2+], or strong [3+]) was determined to describe the immunoreactions. Results: The median age was 52 years in both groups. There were no significant differences in age and sex between the groups (p=0.583, p=0.355, respectively). Of the 26 pterygium specimens, 15 (57.7%) (14 weak, 1 moderate staining) showed HBD-2 expression, which was not observed in any of the control specimens. One (3.8%) pterygium and one (6.7%) control specimen demonstrated weak staining for HBD-3. HBD-2 expression was significantly higher in the pterygium specimens than in the controls (p=0.002). None of the tissue specimens had positive staining for HBD-1 or LL-37 in either group (both; p=1.00). Conclusions: HBD-2 expression was higher in pterygium specimens than in the controls. HBD-2 expression that might be stimulated by inflammatory cytokines may be related to inflammation and fibrovascular proliferation and may play a role in pterygium pathogenesis.


RESUMO Objetivo: Investigar as expressões beta defensinas humanas (HBD) e catelicidina em pacientes com pterígio. Métodos: Nesta série de casos retrospectivos consecutivos, 26 espécimes de pterígio e 15 espécimes conjuntivais normais de 15 indivíduos controle foram investigados. As expressões de HBD-1, HBD-2, HBD-3 e catelicidina (LL-37) foram avaliadas por coloração imuno-histoquímica. Uma cor castanha no citoplasma ou nos núcleos de células epiteliais foi definida como coloração positiva para HBDs e LL-37. Para cada anticorpo foi determinada a intensidade da reação (negativo [-], fraco [1+], moderado [2+] ou forte [3+]) para descrever as imunoreações. Resultados: A idade média foi de 52 anos em ambos os grupos. Não houve diferença significativa entre os grupos em termos de idade e sexo (p=0,583, p=0,355, respectivamente). Das 26 amostras de pterígio, 15 (57,7%) (14 fracas e 1 moderada) demonstraram a expressão de HBD-2 enquanto não foi encontrada em nenhum dos espécimes de controlo. Um dos pterígios (3,8%) e um dos espécimes de controlo (6,7%) demonstraram fraca coloração para HBD-3. A expressão de HBD-2 foi significati vamente maior nos espécimes de pterígio do que nos controles (p=0,002). Nenhum dos espécimes de tecido apresentou coloração positiva para HBD-1 ou LL-37 em ambos os grupos (ambos p=1,00). Conclusão: Encontramos aumento da expressão de HBD-2 em espécimes de pte rígio em relação aos controles. A expressão de HBD-2 que pode ser estimulada por citocinas inflamatórias pode estar relacionada com inflamação e proliferação fibrovascular e pode desempenhar um papel na patogênese do pterígio.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Pterygium/metabolism , Antimicrobial Cationic Peptides/analysis , beta-Defensins/analysis , Reference Values , Biopsy , Immunohistochemistry , Case-Control Studies , Retrospective Studies , Statistics, Nonparametric , Conjunctiva/chemistry
17.
Article in English | WPRIM | ID: wpr-812043

ABSTRACT

Herbal extracts have been extensively used worldwide for their application on memory improvement, especially among aged and memory-deficit populations. In the present study, the memory loss induced by human Abeta protein over-expression in fruitfly Alzheimer's disease (AD) model was rescued by multiple extracts from Gardenia jasminoides. Three extracts that rich with gardenia yellow, geniposide, and gardenoside components showed distinct rescue effect on memory loss. Further investigation on adding gardenoside into a formula of Ganoderma lucidum, Panax notoginseng and Panax ginseng (GPP) also support its therapeutic effects on memory improvement. Interestingly, the application of GPP and gardenoside did not alter the accumulation of Abeta proteins but suppressed the expression of immune-related genes in the brain. These results revealed the importance and relevancy of anti-inflammation process and the underlying mechanisms on rescuing memory deficits, suggesting the potential therapeutic use of the improved GPP formulation in improving cognition in defined population in the future.


Subject(s)
Alzheimer Disease , Drug Therapy , Animals , Antimicrobial Cationic Peptides , Genetics , Brain , Allergy and Immunology , Cognition , Disease Models, Animal , Drosophila , Drosophila Proteins , Genetics , Gardenia , Chemistry , Gene Expression Regulation , Immunity, Innate , Iridoids , Chemistry , Pharmacology , Plant Extracts , Chemistry , Pharmacology , Polymerase Chain Reaction
18.
Araçatuba; s.n; 2017. 83 p. graf, tab, ilus.
Thesis in English, Portuguese | LILACS, BBO | ID: biblio-911426

ABSTRACT

O uso de agentes antimicrobianos naturais que reduzam a adesão e proliferação de S. mutans no biofilme poderia ser uma estratégia interessante para o controle da cárie dentária. No entanto, a estabilidade química e física de alguns desses agentes, como os peptídeos catiônicos antimicrobianos e fragmentos de peptídeos, pode ser comprometida por fatores externos, como temperatura e pH, reduzindo sua ação antimicrobiana. Com isso, os objetivos deste estudo foram desenvolver e caracterizar sistemas de liberação de fármaco nanoestruturados bioadesivos para a incorporação dos fragmentos peptídicos D1-23 e P1025 e avaliar seu efeito citotóxico e atividade contra biofilme de S. mutans. A primeira formulação (F1), composta de ácido oleico, polyoxypropylene-(5)-polyoxyethylene-(20)-cetyl alcohol (PPCA), Carbopol® 974P e Carbopol® 971P, foi analisada por microscopia de luz polarizada (MLP), reologia e bioadesão in vitro. A concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM) de D1-23 foram determinadas contra S. mutans para posterior avaliação da atividade sobre biofilme formado após 4h e 24h de tratamento. A segunda formulação (F2) foi selecionada a partir de três diferentes concentrações de ácido oleico, PPCA e Carbopol® 974P. Cada formulação foi analisada por MLP, espalhamento de raios x a baixo ângulo (SAXS), reologia e bioadesão. CIM e CBM de P1025 sobre S. mutans e seu efeito quando incorporado ou não em F2 sobre biofilme de S. mutans em formação foram analisados. A citotoxicidade em células epiteliais HaCat foi avaliada para os dois sistemas líquido cristalino (SLC) usando testes de MTT. Análise descritiva foi realizada para os dados dos ensaios de caracterização e para os ensaios microbiológicos e citotóxicos os dados foram submetidos aos testes de ANOVA/Tukey ou Kruskall-Wallis/Mann-Whitney U (p<0.05). Os resultados indicaram que F1 apresentou características de SLC com alta viscosidade e bioadesão. CIM e CBM de D1-23 foram de 15,60 e 31,25µg/mL, respectivamente. D1-23 incorporado em F1 apresentou melhores resultados contra biofilme de S. mutans que quando em solução, após 24h de tratamento. F2 apresentou melhores propriedades reológicas e força bioadesiva comparada aos demais sistemas, caracterizando um SLC. P1025 teve somente efeito inibitório sobre S. mutans (CIM=0.25 mg/mL). O efeito antibiofilme de P1025 incorporado em F2 foi observado após 24h de tratamento, principalmente quando aplicado na fase de adesão. Ambos os SLC contendo D1-23 e P1025 não apresentaram toxicidade sobre as células epiteliais, nas condições de tempo e concentrações avaliadas. A incorporação de peptídeos em SLC bioadesivos nanoestruturados aumenta suas propriedades antimicrobianas, podendo ser uma interessante estratégia para a prevenção da cárie dentária(AU)


The use of natural antimicrobial agents for reducing the adhesion and proliferation of S. mutans in the biofilm could be an interesting strategy for the control of dental caries. However, the chemical and physical stability of some natural antimicrobials, such as cationic antimicrobial peptides and peptide fragments, can be compromised by external factors such as temperature and pH, reducing their antimicrobial action. Thus, the objectives of this study were to develop and characterize nanostructured bioadhesive drug delivery systems for the incorporation of D1-23 and P1025 peptide fragments and to evaluate their citotoxicy and activity against S. mutans biofilm. The first formulation (F1) was composed of oleic acid, polyoxypropylene- (5) -polyoxyethylene- (20) - cetyl alcohol (PPCA), Carbopol® 974P and Carbopol® 971P and analyzed by polarized light microscopy (PLM), rheology and in vitro bioadhesion. Minimum inhibitory concentration (MIC) and minimal bacterial concentration (MBC) of D1-23 were determined against S. mutans for further evaluation of activity against S. mutans biofilm after 4h and 24h of treatment. The second formulation was selected from three different concentrations of oleic acid, PPCA and Carbopol® 974P. Each formulation was analyzed by PLM, small-angle x-ray scattering (SAXS), rheology and bioadhesion. MIC and MBC of P1025 were determined against S. mutans. Thus, P1025 was incorporated in the best formulation (F2). The effect of P1025 incorporated or not into F2 on S. mutans biofilm formation was analyzed. Cytotoxicity in HaCat epithelial cells for both formulations was evaluated using MTT assays. Descriptive analysis was performed for the characterization assays and data from microbiological and cytotoxic assays were submitted to ANOVA / Tukey or Kruskall-Wallis / Mann-Whitney U (p<0.05). The results indicated that F1 presented characteristics of liquid-crystalline type system (LCS) with high viscosity and bioadhesion. The MIC and MBC of D1-23 were 15.60 and 31.25µg / mL, respectively. D1-23 incorporated in F1 showed better results than D1-23 in solution against S. mutans biofilm after 24h. F2 had better rheological properties and bioadhesive strength compared to other systems analyzed and characteristics of LCS. P1025 had only inhibitory effect against S. mutans (MIC=0.25mg/mL). The antibiofilm effect of P1025 incorporated into F2 was observed after 24h of treatment, mainly when applied in surface-bound salivary phase. Both LCS had no toxicity on epithelial cells, considering time and concentrations tested. The incorporation of peptides in nanostructured bioadhesive LCS increased their antimicrobial properties and could be an interesting strategy for caries prevention(AU)


Subject(s)
Antimicrobial Cationic Peptides , Dental Caries , Streptococcus mutans , Biofilms , Drug Delivery Systems
19.
Article in Spanish | LILACS | ID: biblio-844743

ABSTRACT

En la actualidad existe consenso en que el daño de los tejidos de soporte dentario que se produce durante la periodontitis es un proceso complejo en el cual la presencia de los patógenos periodontales es necesaria, pero no suficiente, para explicar en su totalidad la extensión y severidad de dicho daño. Asimismo, la destrucción del tejido de soporte periodontal es en gran medida producida por el desbalance de la respuesta inmune generada por el paciente frente a antígenos y factores de virulencia derivados de los patógenos periodontales. Esta respuesta inmune, desencadenada por las bacterias periodontopatógenas, incluye tanto mecanismos asociados a inmunidad innata como adaptativa, siendo el rol de los péptidos antimicrobianos y mediadores lipídicos aspectos relacionados con ambas ramas de la inmunidad y que no han sido completamente dilucidados en relación con sus mecanismos de acción contra los patógenos periodontales. En esta revisión se describe el rol de los péptidos antimicrobianos y de los mediadores lipídicos en la enfermedad periodontal, enfocándonos en su contribución tanto a la protección como a la destrucción del tejido de soporte dentario durante la infección periodontal. Se destaca además la importancia de considerarlos dentro del complejo escenario de la respuesta inmune durante las enfermedades periodontales, ya que forman parte fundamental de la respuesta inmune del hospedero. Analizar la enfermedad periodontal ampliando la perspectiva de estudio a este tipo de moléculas que participan de la respuesta inmune permitiría en el futuro lograr un nuevo enfoque terapéutico de las enfermedades periodontales.


Currently, there is consensus that the damage of the tooth support tissues that occurs during periodontitis is a complex mechanism, in which the presence of specific periodontal pathogens is necessary, but not sufficient, to fully explain the extent and severity of the observed periodontal destruction. Moreover, the destruction of periodontal support tissue is largely the effect of the imbalance in the patient immune response, triggered by periodontal pathogen-derived antigens and virulence factors. The immune response elicited by periodontal pathogenic bacteria includes mechanisms associated with both innate and adaptive responses, where the role of antimicrobial peptides and lipid mediators are related to these two arms of immunity, and have not been fully elucidated in relation to their mechanisms of action against periodontal pathogens. In this review, a discussion is presented on the characteristics of these molecules and their role in periodontal disease in relation to both protection and destruction of tooth supporting tissue during periodontal infection. The relevance of considering these mediators within the complex scenario of the immune response during periodontal diseases is also highlighted, since they are a fundamental part of the host immune response. Periodontal diseases should be analysed in a broader perspective, where the study of these types of molecules involved in the immune response of periodontal tissues, may help to develop new therapeutic approaches to periodontal diseases in the future.


Subject(s)
Humans , Antimicrobial Cationic Peptides/immunology , Docosahexaenoic Acids/immunology , Periodontal Diseases/immunology , Defensins/immunology
20.
International Journal of Mycobacteriology. 2016; 5 (1): 83-88
in English | IMEMR | ID: emr-177667

ABSTRACT

It is estimated that about 40% of the Indian population are infected with tuberculosis [TB] and that 3,000,000 people die as a result of TB annually. TB is caused by Mycobacterium tuberculosis. In 2011, the World Health Organization declared India as having the highest TB burden worldwide. An important criteria for pathogenicity is the presence of mycolic acid linked to the protective outer membrane of bacteria. Mycolyl transferase catalyzes the transfer of mycolic acid and promotes cell wall synthesis. This is also considered as a novel target for drug-mediated intervention strategies. Here, we have attempted to understand the interaction between the antimicrobial peptide [AMP], dermcidin, and mycolyl transferase in M. tuberculosis using a computational approach. The present study was undertaken in order to elucidate the capability of AMPs to treat this bacteria, which is less sensitive to available antibiotics, and to design a novel method for new therapies


Subject(s)
Acyltransferases , Antigens, Bacterial , Antimicrobial Cationic Peptides
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