Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 54
Filter
1.
Adv Exp Med Biol ; 1197: 143-163, 2019.
Article in English | MEDLINE | ID: mdl-31732940

ABSTRACT

Epithelial cells and functions of the epithelium are critical to the health of the oral cavity. We used a nonhuman primate model to profile the transcriptome of gingival tissues in health across the lifespan and hypothesized that in older animals, epithelial-related transcriptome patterns would reflect epithelial cells that are aggressively responsive to the surrounding environment and less able to modulate and resolve the noxious challenge from the bacteria. Rhesus monkeys (n = 34) with a healthy periodontium were distributed into four groups: ≤3 years (young), 3-7 years (adolescent), 12-16 years (adult), and 18-23 years (aged), and a buccal gingival sample from the premolar/molar region of each animal was obtained. RNA was subjected to a microarray analysis (GeneChip® Rhesus Macaque Genome Array, Affymetrix), and 336 genes examined that are linked to epithelium and epithelial cell functions categorized into 9 broad functional groups: extracellular matrix and cell structure; extracellular matrix remodeling enzymes; cell adhesion molecules, cytoskeleton regulation; inflammatory response; growth factors; kinases/cell signaling; cell surface receptors; junction associated molecules; autophagy/apoptosis; antimicrobial peptides; and transcription factors. Total of 255 genes displayed a normalized signal >100, and differences across the age groups were observed primarily in extracellular matrix and cell structure, cell adhesion molecules, and cell surface receptor gene categories with elevations in the aged tissues. Keratins 2, 5, 6B, 13, 16, 17 were all significantly increased in healthy-aged tissues versus adults, and keratins 1 and 2 were significantly decreased in young animals. Approximately 15 integrins are highly expressed in the gingival tissues across the age groups with only ITGA8, ITGAM (CD11b), and ITGB2 significantly increased in the aged tissues. Little impact of aging on desmosomal/hemidesmosomal genes was noted. These results suggest that healthy gingival aging has a relatively limited impact on the broader functions of the epithelium and epithelial cells, with some effects on genes for extracellular matrix and cell adhesion molecules (e.g., integrins). Thus, while there is a substantial impact of aging on immune system targets even in healthy gingiva, it appears that the epithelial barrier remains reasonably molecularly intact in this model system.


Subject(s)
Aging , Epithelial Cells , Gingiva , Transcriptome , Animals , Disease Models, Animal , Epithelial Cells/metabolism , Gingiva/metabolism , Macaca mulatta , Oligonucleotide Array Sequence Analysis
2.
Immunobiology ; 224(2): 196-206, 2019 03.
Article in English | MEDLINE | ID: mdl-30470434

ABSTRACT

Host-derived pattern recognition receptors (PRRs) are necessary for effective innate immune engagement of pathogens that express microbial-associated molecular patterns (MAMP) ligands for these PRRs. This study used a nonhuman primate model to evaluate the expression of these sensing molecules in gingival tissues. Macaca mulatta aged 12-24 with a healthy periodontium (n = 13) or periodontitis (n = 11) provided gingival tissues for assessment of naturally-occurring periodontitis. An additional group of animals (12-23 years; n = 18) was subjected to a 5 month longitudinal study examining the initiation and progression of periodontitis, RNA was isolated and microarray analysis conducted for gene expression of the sensing PRRs. The results demonstrated increased expression of various PRRs in naturally-occurring established periodontitis. Selected PRRs also correlated with both bleeding on probing (BOP) and pocket depth (PD) in the animals. The longitudinal model demonstrated multiple TLRs, as well as selected other PRRs that were significantly increased by 2 weeks during initiation of the lesion. While gene expression levels of various PRRs correlated with BOP and PD at baseline and resolution of disease, few correlated with these clinical parameters during initiation and progression of the lesion. These findings suggest that the levels of various PRRs are affected in established periodontitis lesions, and that PRR expression increased most dramatically during the initiation of the disease process, presumably in response to the juxtaposed microbial challenge to the tissues and goal of reestablishing homeostasis.


Subject(s)
Gene Expression Profiling , Host-Pathogen Interactions/genetics , Mucous Membrane/metabolism , Mucous Membrane/microbiology , Periodontal Diseases/genetics , Periodontal Diseases/microbiology , Transcriptome , Animals , Biomarkers , Disease Models, Animal , Disease Progression , Female , Macaca mulatta , Male , Periodontal Diseases/diagnosis
3.
Immunobiology ; 223(3): 279-287, 2018 03.
Article in English | MEDLINE | ID: mdl-29066255

ABSTRACT

Host-bacterial interactions at mucosal surfaces require recognition of the bacteria by host cells enabling targeted responses to maintain tissue homeostasis. It is now well recognized that an array of host-derived pattern recognition receptors (PRRs), both cell-bound and soluble, are critical to innate immune engagement of microbes via microbial-associated molecular patterns (MAMP). This report describes the use of a nonhuman primate model to evaluate changes in the expression of these sensing molecules related to aging in healthy gingival tissues. Macaca mulatta aged 3-24 years were evaluated clinically and gingival tissues obtained, RNA isolated and microarray analysis conducted for gene expression of the sensing pattern recognition receptors (PRRs). The results demonstrated increased expression of various PRRs in healthy aging gingiva including extracellular (CD14, CD209, CLEC4E, TLR4), intracellular (NAIP, IFIH1, DAI) and soluble (PTX4, SAA1) PRRs. Selected PRRs were also correlated with both bleeding on probing (BOP) and pocket depth (PD) in the animals. These findings suggest that aged animals express altered levels of various PRRs that could affect the ability of the tissues to interact effectively with the juxtaposed microbial ecology, presumably contributing to an enhanced risk of periodontitis even in clinically healthy oral mucosal tissues with aging.


Subject(s)
Aging/immunology , Gingivitis/immunology , Mouth Mucosa/immunology , Periodontitis/immunology , Receptors, Pattern Recognition/metabolism , Animals , Gingiva/immunology , Homeostasis , Host-Pathogen Interactions , Humans , Macaca mulatta , Microarray Analysis , Models, Animal , Pathogen-Associated Molecular Pattern Molecules/immunology , Receptors, Pattern Recognition/genetics , Transcriptome
4.
Mol Oral Microbiol ; 31(1): 18-32, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26197995

ABSTRACT

The molecular changes underlying the higher risk of chronic inflammatory disorders during aging remain incompletely understood. Molecular variations in the innate immune response related to recognition and interaction with microbes at mucosal surfaces could be involved in aging-related inflammation. We developed an ontology analysis of 20 nucleotide-binding and oligomerization domain (NOD)-like receptors (NLRs) and seven inflammasome-related genes (IRGs) in healthy and inflamed/periodontitis oral mucosal tissues from young, adolescent, adult, and aged non-human primates (Macaca mulatta) using the GeneChip(®) Rhesus Macaque Genome array. Validation of some of the significant changes was done by quantitative reverse transcription-polymerase chain reaction. The expression of NLRB/NAIP, NLRP12, and AIM2 increased with aging in healthy mucosa whereas NLRC2/NOD2 expression decreased. Although higher expression levels of some NLRs were generally observed with periodontitis in adult mucosal tissues (e.g. NLRB/NAIP, NLRP5, and NLRX1), various receptors (e.g. NLRC2/NOD2 and NLRP2) and the inflammasome adaptor protein ASC, exhibited a significant reduction in expression in aged periodontitis tissues. Accordingly, the expression of NLR-activated innate immune genes, such as HBD3 and IFNB1, was impaired in aged but not adult periodontitis tissues. Both adult and aged tissues showed significant increase in interleukin-1ß expression. These findings suggest that the expression of a subset of NLRs appears to change with aging in healthy oral mucosa, and that aging-related oral mucosal inflammation could involve an impaired regulation of the inflammatory and antimicrobial response associated with downregulation of specific NLRs and IRGs.


Subject(s)
Aging/genetics , Carrier Proteins/genetics , Inflammasomes/genetics , Mouth Mucosa/metabolism , NLR Proteins/genetics , Animals , Carrier Proteins/biosynthesis , Carrier Proteins/metabolism , Female , Gene Expression , Immunity, Innate/genetics , Inflammasomes/biosynthesis , Inflammasomes/metabolism , Interleukin-1beta/biosynthesis , Macaca mulatta , Male , Mouth Mucosa/immunology , Mouth Mucosa/pathology , NLR Proteins/biosynthesis , NLR Proteins/metabolism , Neuronal Apoptosis-Inhibitory Protein/biosynthesis , Neuronal Apoptosis-Inhibitory Protein/genetics , Neuronal Apoptosis-Inhibitory Protein/metabolism , Periodontitis/genetics , Periodontitis/metabolism , Periodontitis/pathology , RNA, Messenger/biosynthesis , Real-Time Polymerase Chain Reaction , Signal Transduction
5.
J Periodontal Res ; 51(2): 152-63, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26077888

ABSTRACT

BACKGROUND AND OBJECTIVE: Young/adolescent humans harbor many microorganisms associated with periodontal disease in adults and show substantial gingival inflammatory responses. However, younger individuals do not demonstrate the soft- and hard-tissue destruction that hallmark periodontitis. MATERIAL AND METHODS: This study evaluated responses to the oral microbial ecology in gingival tissues from clinically healthy young Macaca mulatta (< 3 years of age) compared with older animals (5-23 years of age). RNA was isolated from the tissues and analyzed for the transcriptome using the Rhesus Macaque GeneChip (Affymetrix). RESULTS: Global transcriptional profiling of four age groups revealed a subset of 159 genes that were differentially expressed across at least one of the age comparisons. Correlation metrics generated a relevance network abstraction of these genes. Partitioning of the relevance network revealed seven distinct communities comprising functionally related genes associated with host inflammatory and immune responses. A group of genes was identified that were selectively increased/decreased or positively/negatively correlated with gingival profiles in the animals. A principal components analysis created metagenes of expression profiles for classifying the 23 animals. CONCLUSION: The results provide novel system-level insights into gene-expression differences in gingival tissues from healthy young animals, weighted toward host responses associated with anti-inflammatory biomolecules or those linked with T-cell regulation of responses. The combination of the regulated microenvironment may help to explain the apparent 'resistance' of younger individuals to developing periodontal disease.


Subject(s)
Gingiva , Animals , Immune System , Macaca mulatta , Oligonucleotide Array Sequence Analysis , Periodontitis , Transcriptome
6.
Immunol Invest ; 44(7): 643-64, 2015.
Article in English | MEDLINE | ID: mdl-26397131

ABSTRACT

Recent evidence has determined a phenotypic and functional heterogeneity for macrophage populations. This plasticity of macrophage function has been related to specific properties of subsets (M1 and M2) of these cells in inflammation, adaptive immune responses and resolution of tissue destructive processes. This investigation hypothesized that targeted alterations in the distribution of macrophage phenotypes in aged individuals, and with periodontitis would be skewed towards M1 inflammatory macrophages in gingival tissues. The study used a non-human primate model to evaluate gene expression profiles as footprints of macrophage variation in healthy and periodontitis gingival tissues from animals 3-23 years of age and in periodontitis tissues in adult and aged animals. Significant increases in multiple genes reflecting overall increases in macrophage activities were observed in healthy aged tissues, and were significantly increased in periodontitis tissues from both adults and aged animals. Generally, gene expression patterns for M2 macrophages were similar in healthy young, adolescent and adult tissues. However, modest increases were noted in healthy aged tissues, similar to those seen in periodontitis tissues from both age groups. M1 macrophage gene transcription patterns increased significantly over the age range in healthy tissues, with multiple genes (e.g. CCL13, CCL19, CCR7 and TLR4) significantly increased in aged animals. Additionally, gene expression patterns for M1 macrophages were significantly increased in adult health versus periodontitis and aged healthy versus periodontitis. The findings supported a significant increase in macrophages with aging and in periodontitis. The primary increases in both healthy aged tissues and, particularly periodontitis tissues appeared in the M1 phenotype.


Subject(s)
Aging/genetics , Gingiva/metabolism , Macrophages/metabolism , Periodontitis/genetics , Transcriptome , Age Factors , Aging/immunology , Animals , Disease Models, Animal , Female , Gene Expression Profiling , Gene Expression Regulation , Gingiva/immunology , Gingiva/pathology , Macaca mulatta , Macrophage Activation/genetics , Macrophage Activation/immunology , Macrophages/immunology , Male , Periodontitis/immunology
7.
J Rural Health ; 31(2): 206-16, 2015.
Article in English | MEDLINE | ID: mdl-25252080

ABSTRACT

PURPOSE: In rural communities that experience high rates of cardiovascular disease (CVD) morbidity and mortality, family history education may enhance risk awareness and support engagement in healthy behaviors but could also engender fatalism. This study was conducted to assess if the relationship between family history and adherence to healthy lifestyle behaviors is moderated by fatalism. METHODS: Baseline data were obtained from 1,027 adult participants in the HeartHealth in Rural Kentucky study. Multiple linear regression was used to determine whether fatalism moderated the relationship between high-risk family history of CVD and adherence to healthy lifestyle behaviors, controlling for sociodemographic variables and CVD risk factors. The relationship between family history and healthy behaviors was assessed for subgroups of participants divided according to the upper and lower quartiles of fatalism score. FINDINGS: The relationship between high-risk family history of CVD and adherence to healthy behaviors was moderated by fatalism. Among those with the highest quartile of fatalism scores, high-risk family history predicted greater adherence to healthy behaviors, while among those in the lowest quartile, and among those with the middle 50% of fatalism scores, there was no association between family history and healthy behavior scores. CONCLUSIONS: Family history education can provide people at increased risk for CVD important information to guide health practices. This may be particularly relevant for those with a high degree of fatalistic thinking. In rural communities with limited health resources, family history education, combined with assessment of fatalism, may support better targeted interventions to enhance engagement in healthy behaviors.


Subject(s)
Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/psychology , Health Behavior , Health Knowledge, Attitudes, Practice , Rural Population/statistics & numerical data , Adult , Aged , Aged, 80 and over , Female , Humans , Kentucky/epidemiology , Life Style , Linear Models , Male , Medical History Taking , Middle Aged , Risk Factors , Young Adult
8.
J Dent Res ; 93(7 Suppl): 72S-79S, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24879575

ABSTRACT

The comparative utility of serum and saliva as diagnostic fluids for identifying biomarkers of acute myocardial infarction (AMI) was investigated. The goal was to determine if salivary biomarkers could facilitate a screening diagnosis of AMI, especially in cases of non-ST elevation MI (NSTEMI), since these cases are not readily identified by electrocardiogram (ECG). Serum and unstimulated whole saliva (UWS) collected from 92 AMI patients within 48 hours of chest pain onset and 105 asymptomatic healthy control individuals were assayed for 13 proteins relevant to cardiovascular disease, by Beadlyte technology (Luminex(®)) and enzyme immunoassays. Data were analyzed with concentration cut-points, ECG findings, logistic regression (LR) (adjusted for matching for age, gender, race, smoking, number of teeth, and oral health status), and classification and regression tree (CART) analysis. A sensitivity analysis was conducted by repetition of the CART analysis in 58 cases and 58 controls, each matched by age and gender. Serum biomarkers demonstrated AMI sensitivity and specificity superior to that of saliva, as determined by LR and CART. The predominant discriminators in serum by LR were troponin I (TnI), B-type natriuretic peptide (BNP), and creatine kinase-MB (CK-MB), and TnI and BNP by CART. In saliva, LR identified C-reactive protein (CRP) as the biomarker most predictive of AMI. A combination of smoking tobacco, UWS CRP, CK-MB, sCD40 ligand, gender, and number of teeth identified AMI in the CART decision trees. When ECG findings, salivary biomarkers, and confounders were included, AMI was predicted with 80.0% sensitivity and 100% specificity. These analyses support the potential utility of salivary biomarker measurements used with ECG for the identification of AMI. Thus, saliva-based tests may provide additional diagnostic screening information in the clinical course for patients suspected of having an AMI.


Subject(s)
Biomarkers/analysis , Myocardial Infarction/diagnosis , Saliva/chemistry , Adult , Aged , Biomarkers/blood , C-Reactive Protein/analysis , CD40 Ligand/analysis , Case-Control Studies , Cohort Studies , Creatine Kinase, MB Form/blood , Cross-Sectional Studies , Decision Trees , Dentition , Early Diagnosis , Electrocardiography/methods , Female , Health Status , Humans , Male , Middle Aged , Myocardial Infarction/blood , Natriuretic Peptide, Brain/blood , Oral Health , Salivary Proteins and Peptides/analysis , Sensitivity and Specificity , Sex Factors , Smoking , Troponin I/blood
9.
Article in English | MEDLINE | ID: mdl-24630161

ABSTRACT

OBJECTIVE: This investigation tested the hypothesis that systemic inflammatory responses would be attenuated by minimizing the oral microbial burden in patients with moderate to severe periodontitis. STUDY DESIGN: Patients (n = 73) scheduled for full-mouth extractions were categorized as case type I/II (gingivitis/mild periodontitis) or case type III/IV (moderate/severe periodontitis). Serum levels of acute phase proteins (APPs) and immunoglobulin G (IgG) antibody were assessed at baseline and through 1 year after extraction. RESULTS: At baseline, the levels of multiple APPs (e.g., fibrinogen, C-reactive protein) and antibodies to periodontal pathogens were significantly higher with case type III/IV vs I/II. These differences were sustained 12 months after extractions for most APPs. CONCLUSIONS: The results demonstrated that removal of disease by full-mouth extraction of teeth altered the overall burden of challenge to the host. Continued elevation in various APPs in the III/IV group suggested a potential underlying constitutive difference in systemic response characteristics of this population.


Subject(s)
Periodontitis/surgery , Systemic Inflammatory Response Syndrome/blood , Tooth Extraction , Acute-Phase Proteins/metabolism , Adult , Aged , Biomarkers/blood , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunoglobulin G/blood , Longitudinal Studies , Male , Middle Aged , Postoperative Complications/surgery
10.
Am J Health Behav ; 38(1): 134-43, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24034688

ABSTRACT

OBJECTIVE: To explore factors associated with cardiovascular disease (CVD) risk in Central Appalachia Kentucky to guide development of a culturally appropriate risk reduction intervention. METHODS: Based on community-based participatory research principles, 7 focus groups were conducted with 88 healthcare employees and residents from 6 Appalachian counties. Sessions were audio-recorded and transcribed. Thematic analysis was used to identify themes and sub-themes. RESULTS: Participants most frequently attributed CVD risk to behaviors including unhealthy diets, physical inactivity, and smoking, and to inadequate preventive care. Intrapersonal, interpersonal, sociocultural, environmental, organizational, and policy level influences on risk were identified. CONCLUSION: Comprehensive intervention guided by a social ecological framework is needed to address CVD risk reduction in Appalachian Kentucky communities.


Subject(s)
Cardiovascular Diseases/prevention & control , Health Knowledge, Attitudes, Practice , Risk Reduction Behavior , Adult , Aged , Aged, 80 and over , Appalachian Region , Cardiovascular Diseases/etiology , Diet , Female , Focus Groups , Humans , Life Style , Male , Middle Aged , Motor Activity , Risk Factors , Rural Population , Social Environment , Young Adult
11.
Oral Dis ; 18(1): 16-31, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21749581

ABSTRACT

A reduction in calorie intake [caloric restriction (CR)] appears to consistently decrease the biological rate of aging in a variety of organisms as well as protect against age-associated diseases including chronic inflammatory disorders such as cardiovascular disease and diabetes. Although the mechanisms behind this observation are not fully understood, identification of the main metabolic pathways affected by CR has generated interest in finding molecular targets that could be modulated by CR mimetics. This review describes the general concepts of CR and CR mimetics as well as discusses evidence related to their effects on inflammation and chronic inflammatory disorders. Additionally, emerging evidence related to the effects of CR on periodontal disease in non-human primates is presented. While the implementation of this type of dietary intervention appears to be challenging in our modern society where obesity is a major public health problem, CR mimetics could offer a promising alternative to control and perhaps prevent several chronic inflammatory disorders including periodontal disease.


Subject(s)
Caloric Restriction , Inflammation Mediators/antagonists & inhibitors , Inflammation/diet therapy , Adaptive Immunity , Animals , Biomimetics , Cardiovascular Diseases/diet therapy , Chronic Disease , Diabetes Mellitus/diet therapy , Humans , Immunity, Innate , Insulin-Like Growth Factor I/antagonists & inhibitors , Metformin/pharmacology , Periodontitis/diet therapy , Resveratrol , Signal Transduction/drug effects , Sirolimus/pharmacology , Sirtuins/drug effects , Stilbenes/pharmacology , TOR Serine-Threonine Kinases/antagonists & inhibitors
12.
J Dent Res ; 90(7): 880-6, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21471327

ABSTRACT

Cellular and molecular changes of the periodontium associated with a higher prevalence of oral diseases (e.g., chronic periodontitis) in aged populations have received little attention. Since impaired apoptosis during aging appears to be related to chronic inflammatory disorders, we hypothesized that the expression of genes associated with apoptotic processes are altered in aged healthy and periodontitis-affected gingival tissue. Ontology analysis of 88 genes related to apoptotic pathways was performed in gingival biopsies of healthy and periodontitis sites from young, adult, and aged non-human primates (Macaca mulatta), using the GeneChip® Rhesus Macaque Genome Array. Lower expression of anti-apoptotic and higher expression of pro-apoptotic genes were associated with healthy gingival tissue from young compared with aged animals. Few differences in gene expression were observed in healthy gingival tissue between adult and aged animals. Comparison between healthy and periodontitis gingival tissues showed that the up- or down-regulated apoptotic genes in diseased gingival tissue are different in adults compared with aged animals. These results suggest that apoptotic events normally occurring in gingival tissues could be reduced in aging,and unique aspects of apoptotic pathways are potentially involved in the pathophysiology of periodontal disease in adult vs. aged gingival tissues.


Subject(s)
Aging/genetics , Apoptosis/genetics , Gingiva/cytology , Gingiva/pathology , Periodontitis/genetics , Animals , Female , Gene Expression Profiling , Macaca mulatta , Male , Oligonucleotide Array Sequence Analysis
13.
J Periodontal Res ; 45(1): 1-7, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20465752

ABSTRACT

BACKGROUND AND OBJECTIVE: Periodontal disease has been linked with an increased risk of various systemic diseases. A plausible biologic explanation for this link includes the opportunity for oral pathogens to translocate to the circulation as a result of breakdown in integrity of the oral epithelium. This study refined a methodology used to detect endotoxin activity in the serum of subjects with indolent periodontal infections. MATERIAL AND METHODS: The QCL Kinetic Chromogenic Assay (Cambrex) is a kinetic measure of endotoxin activity. Sera from 211 pregnant women with periodontitis enrolled in the Obstetrics and Periodontal Therapy Trial were used to develop the assay further and to evaluate the detection of endotoxin activity that might accompany a low-level bacteremia in chronic periodontitis. RESULTS: We optimized the system to increase the sensitivity and reproducibility of the assay. The refined system was able to detect endotoxin activity in serum at > 0.0125 EU/mL. At baseline (13-16 wk of gestation), 35.5% of the women were positive for endotoxin activity (1.62 +/- 2.21; range: 0.38-15 EU/mL). CONCLUSION: This report describes a sensitive measure of endotoxin activity in serum. The procedure allowed us to document levels of this microbial virulence factor in serum of individuals with indolent infections such as periodontal disease.


Subject(s)
Chronic Periodontitis/blood , Endotoxins/blood , Pregnancy Complications/blood , Bacteremia/blood , Chromogenic Compounds , Chronic Periodontitis/classification , Chronic Periodontitis/therapy , Escherichia coli , Female , Follow-Up Studies , Gingival Hemorrhage/blood , Gingival Hemorrhage/classification , Humans , Infant, Low Birth Weight , Infant, Newborn , Limulus Test , Periodontal Attachment Loss/blood , Periodontal Attachment Loss/classification , Periodontal Pocket/blood , Periodontal Pocket/classification , Pregnancy , Pregnancy Complications/classification , Pregnancy Complications/therapy , Premature Birth , Reproducibility of Results , Sensitivity and Specificity
14.
Toxicol Appl Pharmacol ; 234(1): 128-34, 2009 Jan 01.
Article in English | MEDLINE | ID: mdl-18977373

ABSTRACT

The biochemical sequelae to chloroethyl mustard exposure correspond very well to toxic processes initiated by free radicals. Additionally, mustard solutions contain spontaneously formed cyclic onium ions which produce carbon free radicals when reduced electrochemically. Therefore, we hypothesized that the onium ions of sulfur or nitrogen mustards might produce carbon free radicals upon being reduced enzymatically, and that these radicals might constitute a metabolic activation. We set out to document radical production using an in vitro metabolic system and electron paramagnetic resonance (EPR). Our system consisted of NADPH, one of several pyridine nucleotide-driven flavoprotein reductases, cytochrome c as a terminal electron acceptor, various sulfur or nitrogen mustards and the spin trap alpha-[4-pyridyl-1-oxide]-N-tert-butylnitrone in buffer. Reactions were started by adding the reductase to the other materials, vortexing and immediately transferring the mixture to a 10 mm EPR flat cell. Repeated scans on a Bruker ESP 300E EPR spectrometer produced a triplet of doublets with hyperfine splitting constants of a(N)=15.483 G and a(H)=2.512 G. The outcome supported our hypothesis that carbon-centered free radicals are produced when mustard-related onium ions are enzymatically reduced. The EPR results varied little with the chloroethyl compound used or with porcine or human cytochrome P450 reductase, the reductase domain of rat brain neuronal nitric oxide synthase or rat liver thioredoxin reductase. Our results offer new insight into the basis for mustard-induced vesication and the outcome of exposure to different mustards. The free radical model provides an explanation for similarities in the lesions arising from mustard exposure and energy-based lesions such as those from heat, ultraviolet and nuclear radiation as well as damage across tissue types such as skin, eyes or airway epithelium.


Subject(s)
Chemical Warfare Agents/toxicity , Free Radicals/metabolism , Mustard Gas/toxicity , NADP/metabolism , Nitrogen Mustard Compounds/toxicity , Animals , Brain/metabolism , Cytochromes c/metabolism , Electron Spin Resonance Spectroscopy , Humans , Liver/metabolism , NADPH-Ferrihemoprotein Reductase/metabolism , Nitric Oxide Synthase/metabolism , Pyridines , Rats , Spin Trapping , Swine , Thioredoxin-Disulfide Reductase/metabolism
15.
Open Dent J ; 2: 49-55, 2008.
Article in English | MEDLINE | ID: mdl-19088882

ABSTRACT

Quantitative PCR (qPCR) has recently been used to quantify microorganisms in complex communities, including dental plaque biofilms. However, there is variability in the qPCR protocols being used. This study was designed to evaluate the validity of two of these variables with the intent of developing a more standardized qPCR protocol. The two variables evaluated were (1) the use of DNA content versus actual cell counts to estimate bacterial numbers in mixed plaque samples and (2) the effectiveness of three different universal primers versus species specific primers in amplifying specific target pathogens in these samples. Results lead to the development of a standardized protocol that was shown to be highly reproducible as demonstrated by low coefficients of variation. The results also confirmed that this standardized qPCR protocol can be used as a sensitive method for quantifying specific bacterial species in human plaque samples.

16.
J Dent Res ; 87(10): 928-31, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18809745

ABSTRACT

We have recently demonstrated that extracorporeal shock-wave therapy (ESWT) is effective in promoting the healing of dermal wounds and in regenerating alveolar bone lost through periodontal disease. The objective of the present study was to determine any antibacterial effect of ESWT on oral bacteria. Monoculture suspensions of 6 bacterial species were treated with 100 to 500 pulses of ESWT at energy flux densities (EFD) of 0.12 mJ/mm(2), 0.22 mJ/mm(2), and 0.3 mJ/mm(2). Following treatment, aliquots were plated for viability determination and compared with untreated controls. ESWT showed a significant microbicidal effect for Streptococcus mutans and an unencapsulated strain of Porphyromonas gingivalis following as few as 100 pulses at 0.3 mJ/mm(2) (p 0.05). These findings suggest that low-energy ESWT may be bactericidal for selected oral bacteria.


Subject(s)
Porphyromonas gingivalis/radiation effects , Radiation, Nonionizing , Streptococcus mutans/radiation effects , Actinomyces/radiation effects , Analysis of Variance , Bacterial Adhesion/radiation effects , Colony Count, Microbial , Fusobacterium nucleatum/radiation effects , Microbial Viability/radiation effects , Radiation Dosage , Staphylococcus aureus/radiation effects , Statistics, Nonparametric
17.
J Periodontal Res ; 43(5): 500-7, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18565132

ABSTRACT

BACKGROUND AND OBJECTIVE: Dietary manipulation, including caloric restriction, has been shown to impact host response capabilities significantly, particularly in association with aging. This investigation compared systemic inflammatory and immune-response molecules in rhesus monkeys (Macaca mulatta). MATERIAL AND METHODS: Monkeys on continuous long-term calorie-restricted diets and a matched group of animals on a control ad libitum diet, were examined for systemic response profiles including the effects of both gender and aging. RESULTS: The results demonstrated that haptoglobin and alpha1-antiglycoprotein levels were elevated in the serum of male monkeys. Serum IgG responses to Campylobacter rectus, Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were significantly elevated in female monkeys. While only the antibody to Fusobacterium nucleatum was significantly affected by the calorie-restricted diet in female monkeys, antibody levels to Prevotella intermedia, C. rectus and Treponema denticola demonstrated a similar trend. CONCLUSION: In this investigation, only certain serum antibody levels were influenced by the age of male animals, which was seemingly related to increasing clinical disease in this gender. More generally, analytes were modulated by gender and/or diet in this oral model system of mucosal microbial challenge.


Subject(s)
Aging/physiology , Caloric Restriction , Inflammation/immunology , Sex Factors , Acute-Phase Proteins/analysis , Animals , Antibodies, Bacterial/blood , Bacteria, Anaerobic/immunology , Female , Immunity, Mucosal/physiology , Immunoglobulin G/blood , Inflammation/blood , Linear Models , Macaca mulatta , Male , Periodontal Diseases/immunology , Periodontal Diseases/microbiology
18.
J Dent Res ; 87(7): 687-91, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18573992

ABSTRACT

UNLABELLED: Periodontal inflammation with alveolar bone resorption is a hallmark of periodontitis. We hypothesized that extracorporeal shock wave therapy (ESWT) could promote the regeneration of alveolar bone following Porphyromonas gingivalis-induced periodontitis in rats. Rats were infected with P. gingivalis for 10 wks, which caused alveolar bone resorption. The rats were then treated with a single episode of 100, 300, or 1000 impulses of shock wave on both cheeks at energy levels 0.1 mJ/mm(2). Alveolar bone levels were determined at 0, 3, 6, and 12 wks following ESWT and compared with those in untreated controls. Infected rats treated with 300 and 1000 impulses demonstrated significantly improved alveolar bone levels at 3 wks compared with untreated controls, and the improved levels remained for at least 6 wks in most rats. The results demonstrated effective regeneration of alveolar bone by ESWT and suggested that ESWT should be evaluated as an adjunct in the regeneration of periodontal tissues following periodontal disease. ABBREVIATIONS: ESWT, extracorporeal shock wave therapy; PCR, polymerase chain-reaction.


Subject(s)
Alveolar Bone Loss/radiotherapy , Bone Regeneration/radiation effects , Bone Resorption/radiotherapy , High-Energy Shock Waves/therapeutic use , Alveolar Bone Loss/etiology , Alveolar Bone Loss/microbiology , Animals , Bacteroidaceae Infections/complications , Bone Resorption/etiology , Bone Resorption/microbiology , Disease Models, Animal , Female , Gingivitis/complications , Gingivitis/microbiology , Porphyromonas gingivalis , Rats , Rats, Sprague-Dawley
19.
Clin Vaccine Immunol ; 15(7): 1067-75, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18448617

ABSTRACT

This report evaluated systemic inflammatory and immune biomarkers in a cohort of Macaca mulatta (rhesus monkeys) maintained as a large family social unit, including an age range from <1 year to >24 years. We hypothesized that the systemic host responses would be affected by the age, gender, and clinical oral presentation of the population, each contributing to inflammatory and immune responses that would reflect chronic oral infections. The results demonstrated that the prevalence and severity of periodontitis, including missing teeth, increased significantly with age. Generally, minimal differences in clinical parameters were noted between the genders. Systemic inflammatory mediators, including acute-phase reactants, prostaglandin E(2) (PGE(2)), cytokines/chemokines, and selected matrix metalloproteinases (MMP), demonstrated significant differences among the various age groups of animals. Levels of many of these were increased with age, although PGE(2), RANTES, bactericidal permeability-inducing factor (BPI), MMP-1, and MMP-9 levels were significantly increased in the young group ( approximately 1 to 3 years old) relative to those for the older animals. We observed that in the adult and aged animals, levels of the systemic inflammatory mediators related to gingival inflammation and periodontal tissue destruction were significantly elevated. Serum antibody levels in response to a battery of periodontal pathogens were generally lower in the young animals, <50% of those in the adults, and were significantly related to aging in the cohort. The levels of antibodies, particularly those to Porphorymonas gingivalis, Fusobacterium nucleatum, and Tannerella forsythia, were most significantly elevated in animals with periodontal disease, irrespective of the age of the animal. These results provide a broad description of oral health and host responses in a large cohort of nonhuman primates from very young animals to the aged of this species. The findings afford a base of data with which to examine the ontogeny of host responses at mucosal sites, such as the gingival tissues.


Subject(s)
Antibodies, Bacterial/blood , Inflammation Mediators/blood , Macaca mulatta , Monkey Diseases/immunology , Periodontitis/veterinary , Aging , Animals , Bacteria/immunology , Bacteria/pathogenicity , Bacteroidetes/immunology , Fusobacterium nucleatum/immunology , Inflammation , Male , Monkey Diseases/microbiology , Periodontitis/immunology , Periodontitis/microbiology , Porphyromonas gingivalis/immunology , Sex Characteristics
20.
Toxicol Mech Methods ; 16(7): 373-7, 2006.
Article in English | MEDLINE | ID: mdl-20021010

ABSTRACT

Reported myocardial pathology resulting from increased levels of catecholamines in vivo has led us to investigate the effect of adrenalin on the gap junction proteins connexin 40 (Cx40) and Cx43 and the possible relationship to vascular toxicity. Adrenalin and its known metabolites, adrenochrome and adrenolutin, were used in this study. Utilizing the A7r5 rat aortic cell line, we evaluated the effects of adrenalin, adrenochrome, and adrenolutin on the expression and function of connexin 40 and 43 that are present in both cardiac and vascular tissues.

SELECTION OF CITATIONS
SEARCH DETAIL
...