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Background: Non-human primates appear to represent the most faithful model of human disease, but to date the oral microbiome in macaques has not been fully characterized using next-generation sequencing. Objective: In the present study, we characterized the clinical and microbiological features of naturally occurring periodontitis in non-human primates (Macaca mulatta). Design: Clinical parameters of periodontitis including probing pocket depth (PD) and bleeding on probing (BOP) were measured in 40 adult macaques (7-22 yrs), at six sites per tooth. Subgingival plaque was collected from diseased and healthy sites, and subjected to 16S rDNA sequencing and identification at the species or higher taxon level. Results: All macaques had mild periodontitis at minimum, with numerous sites of PD ≥ 4 mm and BOP. A subset (14/40) had moderate-severe disease, with >2 sites with PD ≥ 5mm, deeper mean PD, and more BOP. Animals with mild vs moderate-severe disease were identical in age, suggesting genetic heterogeneity. 16S rDNA sequencing revealed that all macaques had species that were identical to those in humans or closely related to human counterparts, including Porphyromonas gingivalis which was present in all animals. Diseased and healthy sites harboured distinct microbiomes; however there were no significant differences in the microbiomes in moderate-severe vs. mild periodontitis. Conclusions: Naturally occurring periodontitis in older macaques closely resembles human adult periodontitis, thus validating a useful model to evaluate novel anti-microbial therapies.
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This study evaluated the alveolar bone response to testosterone and the impact of Resolvin D2 (RvD2) on testosterone-induced osteoblast function. For the in vivo characterization, 60 male adult rats were used. Treatments established sub-physiologic (L), normal (N), or supra-physiologic (H) concentrations of testosterone. Forty rats were subjected to orchiectomy; 20 rats received periodical testosterone injections while 20 rats received testicular sham-operation. Four weeks after the surgeries, 10 rats in each group received a subgingival ligature around the lower first molars to induce experimental periodontal inflammation and bone loss. In parallel, osteoblasts were differentiated from neonatal mice calvariae and treated with various doses of testosterone for 48 h. Cell lysates and conditioned media were used for the determination of alkaline phosphatase, osteocalcin, RANKL, and osteoprotegerin. Micro-computed tomography linear analysis demonstrated that bone loss was significantly increased for both L and H groups compared to animals with normal levels of testosterone. Gingival IL-1ß expression was increased in the L group (p<0.05). Ten nM testosterone significantly decreased osteocalcin, RANKL, and OPG levels in osteoblasts; 100 nM significantly increased the RANKL:OPG ratio. RvD2 partially reversed the impact of 10 nM testosterone on osteocalcin, RANKL, and OPG. These findings suggest that both L and H testosterone levels increase inflammatory bone loss in male rats. While low testosterone predominantly increases the inflammatory response, high testosterone promotes a higher osteoblast-derived RANKL:OPG ratio. The proresolving mediator RvD2 ameliorates testosterone-derived downregulation of osteocalcin, RANKL, and OPG in primary murine osteoblasts suggesting a direct role of inflammation in osteoblast function.
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Huesos/metabolismo , Huesos/patología , Inflamación/metabolismo , Inflamación/patología , Testosterona/farmacología , Fosfatasa Alcalina/metabolismo , Animales , Huesos/diagnóstico por imagen , Huesos/efectos de los fármacos , Células Cultivadas , Citocinas/metabolismo , Ácidos Docosahexaenoicos/farmacología , Regulación hacia Abajo/efectos de los fármacos , Inflamación/sangre , Masculino , Ratones , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteoblastos/patología , Osteocalcina/metabolismo , Osteoprotegerina/metabolismo , Enfermedades Periodontales/sangre , Ligando RANK/metabolismo , Ratas , Testosterona/sangre , Microtomografía por Rayos XRESUMEN
AIM: To evaluate the effects of topical Resolvin E1 (RvE1) application on infected dental pulps. METHODOLOGY: Forty-two male Wistar rats (n = 6 per three groups/and two time periods) were used. To induce inflammation, pulps in mandibular right first molars were accessed and then left exposed to the oral environment for 24 h. After this period, topical medication with a corticosteroid/antibiotic blend, or RvE1, or its vehicle (Ethanol 0.1%) was directly applied onto the pulp tissue and teeth were restored with silver amalgam. The effects of the protocols were evaluated histologically and compared with control pulps not exposed to the oral environment. The inflammatory changes after 24 and 72 h were assessed through a scoring method and analysed using the Kruskal-Wallis test followed by Dunn's. Differences were considered significant if P < 0.05 (CI = 95%). RESULTS: Ethanol and corticosteroid/antibiotic treatment were not effective in arresting severe inflammatory alterations of exposed pulps at 24 and 72 h (P < 0.05, CI = 95%). At both time periods, RvE1 treatment led to a reduction of tissue cellularity and extent of inflammation, whose changes were not different from control pulps (P > 0.05, CI = 95%). CONCLUSIONS: A protective role for RvE1 in pulp inflammation was observed even in the presence of contamination, suggesting that it may be a candidate for a novel therapeutic strategy for conservative dental pulp treatment.
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Pulpa Dental/efectos de los fármacos , Ácido Eicosapentaenoico/análogos & derivados , Corticoesteroides/administración & dosificación , Corticoesteroides/farmacología , Animales , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Pulpa Dental/patología , Ácido Eicosapentaenoico/farmacología , Masculino , Ratas , Ratas WistarRESUMEN
Southwest Metropolitan Mexico City (SWMMC) atmosphere is a complex mixture of air pollutants, including ozone, particulate matter, and aldehydes. Children in SWMMC are exposed chronically and sequentially to numerous toxicants, and they exhibit significant nasal damage. The objective of this study was to assess p53 accumulation by immunohistochemistry in nasal biopsies of SWMMC children. We evaluated 111 biopsies from 107 children (83 exposed SWMMC children and 24 control children residents in a pollutant-compliant Caribbean island). Complete clinical histories and physical examinations, including an ear-nose-throat (ENT) exam were done. There was a significant statistical difference in the upper and lower respiratory symptomatology and ENT findings between control and exposed children (p < 0.001). Control children gave no respiratory symptomatology in the 3 months prior to the study; their biopsies exhibited normal ciliated respiratory epithelium and were p53-negative. SWMMC children complained of epistaxis, nasal obstruction. and crusting. Irregular areas of whitish-gray recessed mucosa over the inferior and middle turbinates were seen in 25% of SWMMC children, and their nasal biopsies displayed basal cell hyperplasia, decreased numbers of ciliated and goblet cells, neutrophilic epithelial infiltrates, squamous metaplasia. and mild dysplasia. Four of 21 SWMMC children with grossly abnormal mucosal changes exhibited strong transmural nuclear p53 staining in their nasal biopsies (p 0.005, odds ratio 26). In the context of lifetime exposures to toxic and potentially carcinogenic air pollutants, p53 nasal induction in children could potentially represent. a) a checkpoint response to toxic exposures, setting up a selective condition for p53 mutation, or b) a p53 mutation has already occurred as a result of such selection. Because the biological significance of p53 nuclear accumulation in the nasal biopsies of these children is not clear at this point, we strongly suggest that children with macroscopic nasal mucosal abnormalities should be closely monitored by the ENT physician. Parents should be advised to decrease the children's number of outdoor exposure hours and encourage a balanced diet with an important component of fresh fruits and vegetables.
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Contaminantes Atmosféricos/efectos adversos , Exposición por Inhalación/efectos adversos , Mucosa Nasal/efectos de los fármacos , Biopsia , Niño , Epitelio/efectos de los fármacos , Epitelio/metabolismo , Epitelio/patología , Femenino , Humanos , Técnicas para Inmunoenzimas , Masculino , México , Mucosa Nasal/metabolismo , Mucosa Nasal/patología , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
To use the equilibrium established by creatine kinase (CK) to determine hepatic free ADP levels, the transcriptional control elements of the transthyretin gene were used to direct expression of the CK B isozyme to the livers of transgenic mice. Activities of CK ranging from 80-250 mumol per min per g (wet weight) were detected in liver extracts from five founder mice. The CK activity was stably transmitted to subsequent generations. Isozyme gels and immunoblots confirmed that the activity detected in extracts was due to the B isozyme of CK. Immunohistology indicated that the protein was expressed uniformly throughout the liver and was localized primarily to the cytoplasm. 31P NMR spectroscopy was used to detect the metabolic product of the CK reaction, phosphocreatine, demonstrating that the enzyme was active in vivo. The phosphocreatine level fell rapidly during anoxia (t1/2 = 1 min), indicating that the CK reaction was integrated into hepatic energy metabolism. The equilibrium established by CK was used to calculate a hepatic free ADP level of 0.059 +/- 0.004 mumol/g (wet weight). In vivo NMR studies of these mice will be valuable for studying the role of free ADP in regulating liver metabolism.