• A Comparison of the Levels of Salivary Biomarkers between Conventional Smokers and Electronic Cigarette Users (A Pilot Study)

      Faridoun, Afnan; Meiller, Timothy F. (2019)
      Cigarette smoking is known to alter host response and the release of inflammatory mediators and cytokines in the body. Electronic cigarettes were marketed to provide the same sensation of conventional smoking without detrimental health consequences; however, the safety of their use is an area where more research is needed. Utilizing saliva as a diagnostic medium has been rising, however, there is a lack of studies investigating the effect of e-cigarettes on the salivary biomarker profile. The purpose of this pilot project was to evaluate the salivary cytokines, associated with inflammation, and CRP profile in e-cigarette users, and compare that to cigarette smokers and controls in an attempt to assess the influence of the use of e-cigarettes on salivary biomarkers. Statistically significant elevated levels of IL- 1β accompanied by lower mean levels of IL-1RA in e-cigarette users were detected. TNF- α showed elevated values in e-cigarette users similar to conventional smokers.
    • Cyclooxygenase expression and acute inflammatory pain in humans

      Khan, Asma A.; Capra, Norman F. (2002)
      Inhibition of cyclooxygenase (COX) activity is accepted to be the mechanism by which non-steroidal anti-inflammatory drugs (NSAIDs) exert their effects. Two distinct isoforms of COX have been identified: COX-1, which is constitutively expressed; and COX-2, which is primarily inducible by inflammation. It is hypothesized that the therapeutic effects of NSAIDs are attributable to inhibition of COX-2, while the adverse effects result from inhibition of COX-1. This led to the development of selective COX-2 inhibitors, a class of NSAIDs designed to selectively inhibit COX-2. This investigation characterized the expression of COX during acute inflammation and demonstrated the in vivo selectivity of celecoxib, a prototypic selective COX-2 inhibitor. The first study involved collection of biopsies from the oral mucosa of subjects immediately before extraction of their impacted lower third molars. A second biopsy was performed either immediately after surgery, 30, 60 or 120 minutes after surgery, or at pain onset. Messenger ribonucleic acid (mRNA) levels of COX-1 and COX-2 were assessed by RT-PCR. COX-1 mRNA was transiently decreased during the post-surgical period, while COX-2 expression was clearly induced after surgery. COX-2 protein was detected in the vascular endothelial cells, fibroblasts and polymorphonuclear cells in the biopsies.;In the second study, subjects received a dose of either celecoxib 200 mg (a selective COX-2 inhibitor), ibuprofen 600 mg, or placebo 8 hours before surgery and a second dose one hour before extraction of two lower impacted third molars. Microdialysis probes were placed for sample collection under the mucoperiosteal flap raised for surgery. Pain intensity ratings were collected every 20 minutes for 4 hours using a visual analog scale and a category scale. The samples were assayed by enzyme immunoassay for prostaglandin E2 (PGE2) an algesic and proinflammatory prostaglandin, and thromboxane B2 (TxB2). Both celecoxib and ibuprofen had a significant analgesic effect as compared to placebo. Celecoxib suppresses PGE2, a measure of both COX-1 and COX-2, and has no effect on TxB2, which is attributed to COX-1 activity. These data support celecoxib being a selective COX-2 inhibitor in vivo.
    • Long-Term Post-COVID-19 Associated Oral Inflammatory Sequelae

      Alfaifi, Areej; Sultan, Ahmed S.; Montelongo-Jauregui, Daniel; Meiller, Timothy F.; Jabra-Rizk, Mary Ann (2022-03-04)
      The oral cavity remains an underappreciated site for SARS-CoV-2 infection despite the myriad oral conditions observed in COVID-19 patients. Recently, replicating SARS-CoV-2 was found inside salivary epithelial cells resulting in inflammation and atrophy of salivary glands. Saliva possesses healing properties crucial for maintaining the health of the oral mucosa. Specifically, salivary antimicrobial peptides, most notable, histatin-5 exclusively produced in salivary glands, plays a vital role in innate immunity against colonizing microbial species. The demonstration of SARS-CoV-2 destruction of gland tissue where histatin-5 is produced strongly indicate that histatin-5 production is compromised due to COVID-19. Here we present a case of a patient presenting with the patient and matched healthy subject for histatin-5 and key cytokines. Findings demonstrated significantly reduced histatin-5 levels in patient’s saliva and activation of the Th17 inflammatory pathway. As histatin-5 exhibits potent activity against the opportunistic oral pathogen Candida albicans, we evaluated saliva potency against C. albicans ex vivo. Compared to control, patient saliva exhibited significantly reduced anti-candidal efficacy. Although speculative, based on history and salivary analysis we hypothesize that salivary histatin-5 production may be compromised due to SARS-CoV-2 mediated salivary gland destruction. With the current lack of emphasis on implications of COVID-19 on oral health, this report may provide lacking mechanistic insights that may lead to reassessment of risks for oral opportunistic infections and mucosal inflammatory processes in acutely-ill and recovered COVID-19 patients.
    • Systemic Response to Chronic Endodontic Pathogens as a Risk Factor for Atherosclerosis

      Blattner, Trevor; Fouad, Ashraf F. (2013)
      INTRODUCTION: For over a decade, it has been hypothesized that microbial agents are responsible for the development of atherosclerotic disease. Prevalent periodontal pathogens including Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Porphyromonas gingivalis, and Prevotella intermedia have all been identified in atheromatous plaques. In addition, a group of epidemiological studies, as well as preliminary animal studies have suggested an association between endodontic disease, systemic inflammation, and cardiovascular disease. The purpose of the present series of studies is to clarify the association between chronic endodontic infections and the systemic immune response to the microbes causing these lesions through an investigation with the following aims: 1. Determine if atheromatous plaques are larger in atherosclerosis susceptible mice with periapical lesions than those without periapical lesions 2. Determine if periapical lesion size in atherosclerosis susceptible mice correlates with the degree of atheromatous plaque formation 3. Systematically review the literature to determine if the levels of systemic inflammatory markers are altered in humans with apical periodontitis compared to those systemic marker levels in humans with healthy periapical status and 4. Determine if systemic antibody levels 8 prevalent microorganisms from chronic primary endodontic infections, are higher in patients with atherosclerosis undergoing endarterectomy compared with those same systemic antibody levels in healthy control patients. METHODS: For aim #1 and aim #2 eight atherosclerosis susceptible female mice (N=8) were obtained and randomly placed into two separate groups of four as follows: 1. with pulp exposure and endodontic inoculation (N=4) - "EI" 2. without pulp exposure (N=4) - "w/o pulp exposure". The mice were euthanized, their aortic arches were dissected for atheroma size measurement, and their mandibles were processed for periapical lesion area measurement. For aim #3 a comprehensive literature search with no language restriction was undertaken to identify all studies that reported on the relationship between AP and circulating or systemic levels of inflammatory markers between 1948 and 2012. Studies with similar outcome variables were grouped and a meta-analysis was performed to evaluate the most prevalent markers. For aim #4, two groups of patients were selected from a cohort at the Veterans Administration Hospital, Baltimore, MD. The experimental group consisted of ten patients with a clinical diagnosis of carotid stenosis who had undergone recent endarterectomy procedures (n=10), and the control group consisted of 14 patients with a diagnosis of varicose veins (n=14). Each patient underwent comprehensive oral examination, and a blood sample was taken for each patient. Bacterial phenotypes associated with primary endodontic infections were used for immuno-checkerboard analysis to identify differences in IgG antibody levels between the groups. RESULTS: Atheromatous plaque sizes were different among the groups, and difference was borderline significant (p =0.06). There was a statistically significant correlation between lesion size and atheroma size among the groups (p=0.001). Apical periodontitis in humans was associated with increased levels of CRP, IL-1, IL-2, IL-6, ADMA, IgA, IgG, and IgM (p < 0.05) as compared to the levels of these markers in humans without apical periodontitis. Antibody levels to F. nucleatum and P. micra were not significantly different among the two groups (p > 0.05). CONCLUSIONS: 1. Exposure to endodontic pathogens leads to the development of periapical lesion area that was associated with larger atheroma formation in an animal model. 2. There was a significant correlation between periapical lesion area and atheroma size in this model. 3. In patients, apical periodontitis showed an association with increased levels of CRP, IL-1, IL-2, IL-6, ADMA, IgA, IgG, and IgM 4. Systemic antibody levels to F. nucleatum and P. micra were not increased in CEA patients compared with healthy controls.
    • The Contribution of TRPV1 S801 Phosphorylation to Nociception and Inflammatory Pain in Vivo

      Joseph, John; Chung, Man-Kyo (2020)
      Transient receptor potential vanilloid subtype 1 (TRPV1) is a nonselective cation permeable channel activated by painful stimuli, such as capsaicin and noxious heat, and enriched in many primary afferent neurons of the pain pathway. During inflammation, chemical mediators activate protein kinases (such as PKC) that phosphorylate TRPV1 and thereby enhance its function, which results in nociceptor sensitization. And this can result in a lower threshold for pain. However, the causal relationships between TRPV1 phosphorylation and pathological pain remain unexplored. To directly investigate the roles of one specific TRPV1 phosphorylation event in vivo, we genetically altered a major PKC phosphorylation site, mouse TRPV1 S801, to alanine. The TRPV1 expression pattern in sensory neurons of S801A knock-in (KI) mice was comparable to that in wildtype (WT) controls. In sensory neurons from KI mice, following the activation of PKC, the usual increase of capsaicin-induced currents was substantially impaired. Thermal hyperalgesia induced by PMA or burn injury in KI was identical to WT. Thermal hyperalgesia was only marginally attenuated in KI mice duirng inflammation. In contrast, PMA-evoked nocifensive responses and hyperalgesia to capsaicin were significantly attenuated in the hindpaws of KI mice. Ongoing pain from inflamed masseter muscle was also reduced in KI mice, and the pain was further inhibited by the TRPV1 antagonist AMG9810. These results suggest that PKC-mediated phosphorylation of TRPV1 S801 contributes to inflammation-mediated sensitization of TRPV1 to ligand, but not heat, in vivo. Further, this suggests that interference with TRPV1 S801 phosphorylation might represent a potential way to reduce inflammatory pain in the clinic, yet spare basal sensitivity and produce fewer side effects than with a more general TRPV1 inhibition.