Experimental Periodontitis Group Research Articles

Bifidobacterium animalis subspecies lactis HN019 can reduce the sequelae of experimental periodontitis in rats modulating intestinal parameters, expression of lipogenic genes, and levels of hepatic steatosis.

To determine whether Bifidobacterium animalis subspecies lactis HN019 (B. lactis HN019) can reduce the sequelae of experimental periodontitis (EP) in rats modulating systemic parameters. This study evaluated the effects of probiotic therapy (PROB) in the prevention of local and systemic damage resulting from EP. Forty-eight rats were allocated into four groups: C (control), PROB, EP, and EP-PROB. PROB (1 × 1010 CFU/mL) administration lasted 8 weeks and PE was induced on the 7th week by placing ligature on the animals' lower first molars. All animals were euthanized in the 9th week of the experiment. Biomolecular analyses, RT-PCR, and histomorphometric analyses were performed. The data obtained were analyzed statistically (ANOVA, Tukey, p < .05). The EP group had higher dyslipidemia when compared to the C group, as well as higher levels of insulin resistance, proteinuria levels, percentages of systolic blood pressure, percentage of fatty hepatocytes in the liver, and expression of adipokines was up-regulated (LEPR, NAMPT, and FABP4). All these parameters (except insulin resistance, systolic blood pressure, LEPR and FABP4 gene expression) were reduced in the EP-PROB group when compared to the EP group. The EP group had lower villus height and crypt depth, as well as a greater reduction in Bacteroidetes and a greater increase in Firmicutes when compared to the EP-PROB group. Greater alveolar bone loss was observed in the EP group when compared to the EP-PROB group. Bifidobacterium lactis HN019 can reduce the sequelae of EP in rats modulating intestinal parameters, attenuating expression of lipogenic genes and hepatic steatosis.

Probiotic consumption can modify the resilience of periodontal tissues in rats under experimental periodontitis.

This study evaluated the effects of systemic administration of Bifidobacterium animalis subsp. lactis HN019 (B. lactis HN019) on experimental periodontitis (EP) in rats. Thirty-two rats were allocated to groups C (control), C-HN019 (probiotic), EP (EP only), and EP-HN019 (EP+probiotic). From day 0, the animals of C-HN019 and EP-HN019 groups received B. lactis HN019 (1×109 CFU/ml) daily. On the 14th day, the animals of EP and EP-HN019 groups received silk ligature around mandibular molars. Animals were euthanized on the 28th day. Samples of oral biofilm, gingival tissues, blood serum, and mandible were obtained for microtomographic, histomorphometric, microbiological, and immunological analyses. Data were statistically analyzed (p<0.05). Group EP-HN019 presented significantly less alveolar bone loss when compared with Group EP in histomorphometric and microtomographic analyses. In gingival tissue and serum, Group EP-HN019 presented lower proinflammatory/anti-inflammatory cytokines ratios than Group EP. Group EP-HN019 showed higher expression of beta-defensins and less TRAP-positive cells than Group EP. Group EP presented higher gene expression of Ifng and lower gene expression of Foxp3 when compared with Group EP-HN019 in gingival tissue. In oral biofilm, EP-HN019 group presented a lower percentage of species similar to Fusobacterium periodonticum and a higher percentage of species similar to Actinomyces gereneseriae, Actinomyces israelli, and Streptococcus gordonii when compared with Group EP. There was a significant increase of B. lactis HN019 after administration of probiotic therapy in oral biofilm of Group EP-HN019. The consumption of B. lactis HN019 promotes a protective effect against alveolar bone loss by modifying local and systemic microbiological and immunoinflammatory parameters.

Effects of Bdellovibrio bacteriovorus HD100 on experimental periodontitis in rats.

The aim of this study was to evaluate the effects of Bdellovibrio bacteriovorus HD100 on experimental periodontitis (EP) in rats. Thirty-two rats were divided into four groups: control, C-HD100 (B. bacteriovorus), EP, and EP-HD100. On day 0, EP was induced by the placement of cotton ligatures around the mandibular first molars (MFMs) in the EP and EP-HD100 groups. In the C-HD100 and EP-HD100 groups, suspensions containing 1×109 PUF/ml of B. bacteriovorus HD100 were topically administered to the subgingival region of MFMs on days 0, 3, and 7. Animals were euthanized on day 14. Morphometrics analyses were performed in hemimandibles. The levels of tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, monocyte chemoattractant protein (MCP)-1, IL-10, IL-1β, transforming growth factor beta (TGF-β), macrophage colony-stimulating factor (M-CSF) and regulated on activation and normal T cell expressed and secreted (RANTES) were determined by enzymatic immunoassays in gingival tissues. Beta defensin (BD)-1, BD-2, and BD-3, Toll-like receptors (TLR)-2 and TLR-4, and a cluster of differentiation (CD)-4, CD-8 and CD-57 were analyzed by immunohistochemistry in hemimandibles. Data were statistically analyzed. The EP group showed greater alveolar bone loss than EP-HD100 (p<.05). The EP-HD100 group showed higher levels of MCP-1, RANTES, IL-10, and TGF-β, lower levels of TNF-α than the EP group (p<.05). No differences were observed in IL-1β, IL-6, and M-CSF levels between EP and EP-HD100 groups. The C-HD100 group had higher IL-6, TNF-α, RANTES, and MCP-1 levels than the control group (p<.05). Regarding BD, the EP-HD100 group showed a larger immunolabeling pattern for BD-1, BD-2, and BD-3 than the EP group (p<.05). No significant differences in the immunolabeling pattern were observed for TLR-2, TLR-4, CD-4, CD-8, and CD-57 between EP and EP-HD100 groups. The topical use of B. bacteriovorus HD100 reduces alveolar bone loss, increases expression of BD, and modulates the cytokines levels on periodontal tissues in rats with EP.

Impact of Bifidobacterium animalis subsp. lactis HN019 probiotic in the prevention of periodontitis associated with immunosuppression.

This study evaluated the effects of the probiotic Bifidobacterium animalis subsp. lactis HN019 (HN019) in the development of experimental periodontitis (EP) in rats submitted to chemotherapy (5-fluorouracil [5FU]). Eighty male rats were divided into the following groups: control (C); treated with 5FU (60mg/kg at day 30 and 40mg/kg at day 32); treated with probiotic (HN019) (daily, for 44 days, starting at day 0); treatment with 5FU and probiotic (5FU-HN019); only EP (EP) (ligature placed on lower first molars at day 30, maintained for 14 days); EP and treatment with 5FU (EP-5FU); EP and treatment with probiotic (EP-HN019); and EP and treatment with 5FU and probiotic (EP-5FU-HN019). Euthanasia occurred at day 44. Morphometric, histomorphometric, microtomographic, immunohistochemical, immunoenzymatic, and gene expressions analyses were performed. The data obtained were statistically analyzed (p<0.05). The EP-5FU-HN019 group showed less bone and connective tissue loss when compared with EP-5FU group, while EP-HN019 and EP-5FU-HN019 groups had greater bone volume than EP and EP-5FU groups, respectively (p<0.05). A decrease in immunostaining for tartrate-resistant acid phosphatase and RANKL, an increase for osteoprotegerin and lower interleukin-1β levels were observed in EP-5FU-HN019 group, when compared with EP-5FU group (p<0.0001). Probiotic therapy led to an increase in the proportions of B. lactis in the feces (p=0.0018), but not in the biofilm, and reduced the expression of Fusobacterium nucleatum and Prevotella intermedia in the biofilm (p<0.0001). B. lactis HN019 reduced the severity of EP in rats submitted to chemotherapy, modulating immunoinflammatory parameters in periodontal tissues and reducing periodontopathogens expression on biofilm in rats submitted to chemotherapy.

Açaí (Euterpe oleracea Mart.) Attenuates Oxidative Stress and Alveolar Bone Damage in Experimental Periodontitis in Rats.

Açaí (Euterpe oleracea Mart.) juice is rich in phenolic compounds with high antioxidant capacity. It has been observed that the use of antioxidants may be an additional strategy to nonsurgical periodontal therapy as well as to prevent alveolar bone loss. Thus, the objective of this study was to investigate the effects of açaí supplementation on experimental periodontitis in rats. Twenty male Rattus norvegicus (Wistar) rats were assigned into control, açaí, experimental periodontitis, and experimental periodontitis with açaí supplementation groups. Periodontitis was induced by placing ligatures around the lower first molars. Animals in the açaí groups received 0.01 mL/g of clarified açaí juice for 14 days by intragastric gavage. At the end of the experimental period, blood was collected to assess the reduced glutathione (GSH), Trolox equivalent antioxidant capacity (TEAC), and lipid peroxidation (TBARS) levels. Moreover, hemimandibles were analyzed by micro-computed tomography (micro-CT) for alveolar bone loss and bone quality. Açaí supplementation increased blood total antioxidant capacity and decreased lipid peroxidation. It also reduced alveolar bone loss when compared to the experimental periodontitis group. Moreover, clarified açaí per se modulated the oxidative biochemistry and bone microstructure. Thus, açaí may be considered a viable alternative for managing periodontal oxidative stress and preventing alveolar bone loss.

Biological Activity of Copaiba in Damage to the Alveolar Bone in a Model of Periodontitis Induced in Rats.

Several studies have investigated the effects of natural products in the treatment of diseases. Traditional Amazonian populations commonly use copaiba due to its well-known anti-inflammatory, antibacterial, and healing properties. In this study, we aimed to investigate the effects of systemic administration of copaiba oleoresin (Copaifera reticulata Ducke) on ligature-induced periodontitis in rats. To do so, 21 adult rats were divided into three groups (n = 7 each): a control group, ligature-induced periodontitis group, and ligature-induced periodontitis group treated with copaiba oleoresin (200 mg/kg/day). The ligature remained from day 0 to 14, and the copaiba oleoresin was administered via oral gavage during the last seven days. On day 14, the animals were euthanized, and mandibles were collected for histopathological evaluation and microcomputed tomography analysis. Our data showed that the administration of copaiba considerably reduced the inflammatory profile. Moreover, copaiba oleoresin limited alveolar bone loss, increased trabecular thickness and bone-to-tissue volume ratio, and decreased the number of trabeculae compared with those of the untreated experimental periodontitis group. Our findings provide pioneering evidence that supports the potential of copaiba oleoresin in reducing periodontitis-induced alveolar bone damage in rats.

Effect of Traditional Drug Therapy and its Combination with Soderm®-Forte and New Injectable Form of Rexod® on the Antioxidant-prooxidant Red Blood Cell System in Rats with Experimental Periodontitis

Background.The development of periodontitis is strongly linked with both periodontopathogenic microflora and antioxidant-proxidant system disorders, which determines the need for the combined use of antimicrobial and antioxidant agents.Objectives.A comparative evaluation of the antioxidant-prooxidant system of red blood cells in rats with experimental periodontitis against the background of the traditional drug therapy and its combination with Soderm®-Forte and new injectable form of Rexod®.Methods.The authors conducted a comparative study of the effect of traditional drug therapy (TDT) and its combination with Soderm®-Forte gel containing silver nanoparticles, recombinant human superoxide dismutase (Rexod®) and new injectable form (NIF) of Rexod® on the condition of the antioxidant-prooxidant system of red blood cells in rats with experimental periodontitis (EP). The experiments were performed on Wistar male rats of 210–230 g. EP was induced by ligature method. The rats were randomly divided into 5 comparable groups of 12 animals: group 1 — with intact periodontium; group 2 — with EP; group 3 — with EP, where TDT was used, including oral irrigation with chlorhexedine (0.05% solution) and application of Septo-Pack dento-gingival dressing; group 4 — with EP, TDT and Soderm®-Forte gel (applied into the periodontal pockets of the lower incisors); group 5 — with EP, TDT in combination with Soderm®-Forte gel and NIF of Rexod®, which was injected intraperitoneally at a dose of 8000 U/kg. Treatment of rats with EP (groups 3–5) was carried out for 12 days. The observation period for all animals lasted 42 days. The biochemical tests and the antioxidant-prooxidant index were used to assess the condition of antioxidant-prooxidant system. Statistical analysis of the obtained results was carried out with parametric and non-parametric methods of Microsoft Excel (Microsoft, USA), Analysis package and AtteStat, as well as Statistica 8.0 (StatSoft, USA) software.Results.The application of TDT against the developed EP caused a moderate positive correction of the indicators of Antioxidant protection system (APS). The enrichment of TDT for the EP animals with Soderm®-Forte and especially Soderm®-Forte in combination with NIF of Rexod® to enhance the APS potential caused more significant positive dynamics of the balance in the antioxidant-prooxidant system compared to TDT.Conclusion.The combination of TDT with Soderm®-Forte and NIF of Rexod® has the most significant positive corrective effect on the condition of antioxidant-prooxidant system of red blood cells in rats with EP in comparison with the complex of TDT with Soderm®-Forte and TDT used separately.

The effects of Lactobacillus reuteri on the inflammation and periodontal tissue repair in rats: A pilot study

ObjectiveThe aim of this study was to evaluate the effects of probiotic (PRO) Lactobacillus reuteri (DSM17938) as an adjuvant to the treatment of experimental periodontitis (EP). Material and methodsFifty-four male adult Wistar rats were included. EP was induced and maintained for 7 days. Subsequently, the ligature was removed and the animals were allocated into three different experimental groups (n = 18/group): EP – no local treatment, the animals received four systemic saline solution (SS) administrations; SRP+SS, the animals underwent SRP treatment, followed by SS administration; and SRP+PRO, the animals received SRP treatment, followed by the systemic administration of PROs (Lactobacillus reuteri ; 0.16 ml/day). Six animals from each group were euthanised at 7, 15 and 30 days. Histological and histometric analyses of alveolar bone loss (BL) and immunohistochemical analyses for TRAP, RANKL, OPG, OCN, and PCNA were performed. Shapiro–Wilk, ANOVA, post-hoc Tukey, Kruskal–Wallis, Student–Newman Keuls were performed. ResultsThe SRP+PRO group presented a reduction in inflammation. At 15 days, a lower BL was observed in the SRP+SS and SRP+PRO groups. Greater immunolabeling was noticed for PCNA at 15 days in the SRP+PRO group than in the SRP+SS group. The SRP+PRO group demonstrated a higher OCN immunolabeling pattern than the EP group at 15 and 30 days. ConclusionThe use of Lactobacillus reuteri as an adjuvant to SRP for the treatment of EP showed promising results in the control of local inflammatory responses, and enhanced the periodontal tissue repair process according to the employed concentration.

Alterations and Correlations of Gut Microbiota and Fecal Metabolome Characteristics in Experimental Periodontitis Rats.

ObjectivesPeriodontitis affects the progression of many diseases, while its detailed mechanism remains unclear. This study hopes to provide new ideas for exploring its mechanism by analyzing the gut microbiota and fecal metabolic characteristics of experimental periodontitis rats.MethodsA total of 10 rats were randomly divided into ligature-induced experimental periodontitis (EP) group and healthy control group. After 4 weeks of the experiment, the feces of all rats were collected for sequencing through 16S ribosomal DNA (rDNA) sequencing technology and liquid chromatography–mass spectrometry (LC–MS).Results16S rDNA sequencing results showed that the β-diversity of gut microbiota was significantly different between the EP and control group, and the levels of dominant genera were different. Compared with the control group, Ruminococcus, Escherichia, and Roseburia were significantly enriched in EP, and Coprococcus, Turicibacter, Lachnospira were significantly decreased. Correlation analysis showed that Roseburia exhibited the highest correlation within the genus. Of 3,488 qualitative metabolites, 164 metabolites were upregulated and 362 metabolites were downregulated in EP. Enrichment analysis showed that periodontitis significantly changed 45 positive/negative ion metabolic pathways. Five KEGG pathways, protein digestion and absorption, tyrosine metabolism, glycolysis/gluconeogenesis, niacin and nicotinamide metabolism, and oxidative phosphorylation, are enriched in both the microbiome and metabolome. Correlation analysis showed that the genera with significant differences in periodontitis were usually significantly correlated with more metabolites, such as Roseburia, Lachnospira, Escherichia, Turicibacter, and Ruminococcus. The genera with the same changing trend tended to have a similar correlation with some certain metabolites. In addition, vitamin D2 and protoporphyrin IX have the most significant correlations with microorganisms.ConclusionOur study reveals that periodontitis alters gut microbiota and fecal metabolites. The correlation analysis of microbiota and metabolome provides a deeper understanding of periodontitis, and also provides a direction for the study of periodontitis affecting other diseases.

Comparison Between Different Delivery Vehicles for the Probiotic Bifidobacterium animalis subsp. lactis HN019 on Experimental Periodontitis in Rats

This study aimed to assess the effects of the probiotic (PROB) Bifidobacterium animalis subsp. lactis HN019 in two different delivery vehicles in experimental periodontitis (EP), including the gene expression for IL-10, IFN-γ, and FOXP3. In total, 32 rats were assigned into groups (n=8): C (control), EP, EP-PROB/Water, and EP-PROB/Milk. The probiotic was administered for 4 weeks, from baseline to euthanasia. Periodontitis was induced by ligatures 14 days after baseline. Data were statistically analyzed (p<0.05). Both probiotic groups presented decreased alveolar bone loss and increased interproximal attachment level than group EP. Also, these parameters were significantly improved in the Milk group when compared with the Water group. EP-PROB/Milk showed higher gene expression for IL-10 and lower for FOXP3 in relation to EP-PROB/Water and EP groups. The use of milk was able to potentiate the protective effects of B. lactis HN019 in rats under EP.

Experimental testing of tannic acid target delivery system for correcting periodontal microcirculation

Objective: to study the effect of the targeted delivery system of tannic acid (TA) in silver alginate microcapsules on the state of gum microvasculature in rats with intact periodontium vs. experimental periodontitis. Materials and Methods. The study was conducted on 90 white rats, distributed among six groups: the control group, two groups with intact periodontium and single application of gel with microcapsules loaded/not loaded with TA, experimental periodontitis group, and two groups of animals with periodontitis and repeated application of gel with microcapsules loaded/not loaded with TA. We assessed gingival perfusion and blood flow modulation mechanisms in rats via laser Doppler flowmetry. Results. Applying gel with silver microcapsules to an intact gum in rats caused 7.5% transient increase in perfusion and activation of microcirculation modulation. Loading microcapsules with TA reduced the severity of transient microcirculatory changes. Using gel with TA-loaded capsules in rats with periodontitis allowed achieving a more pronounced normalization of perfusion and mechanisms of microcirculation modulation vs. using gel containing microcapsules without active components. Conclusion. Loading alginate microcapsules with silver ions and TA yielded reduction of the irritating effect on gingival mucosa accompanied by an increase in the effectiveness of correcting microcirculatory disorders in periodontitis.

Deneysel Periodontitiste Kafeik Asit Fenetil Esterin Diş Eti Doku İnflamasyonuna Etkisi: Deneysel Çalışma

Objective: This study aimed to investigate the anti-inflammatory effect of two different dosages of caffeic acid phenethyl ester (CAPE) on lipopolysaccharide-induced experimental periodontitis (EP). Material and Methods: Forty Sprague Dawley rats were randomly divided into four groups: control, EP, EP treated with 5 μmol/kg/day of CAPE (EP+CAPE 5), and EP treated with 10 μmol/kg/day of CAPE (EP+CAPE 10). Followed by the EP, CAPE was administered intraperitoneally to the EP+CAPE groups for 28 days. Samples were investigated biochemically using an enzyme-linked immunosorbent assay kit and alveolar bone loss was measured morphometrically. Results: In both of the CAPE groups, the levels of interleukin-1 beta and tumor necrosis factor alpha (TNF-α) in the gingiva were significantly lower than those in the EP group (p<0.001). The decrease in tissue levels of TNF-α was greater in the EP+CAPE 10 group than in the EP+CAPE 5 group in a dose-dependent manner. Serum analysis of the cytokines showed no significant difference between the groups. Conclusion: Within the limits of this study, CAPE showed an anti-inflammatory effect and is claimed to be a novel agent in improving the results of periodontal therapy. CAPE may be valuable as an alternative host modulating agent for the treatment of periodontal disease.

Milk Kefir therapy reduces inflammation and alveolar bone loss on periodontitis in rats

Periodontitis is a chronic inflammatory disease that affects the tooth-supporting tissues. This study evaluated the anti-inflammatory and antiresorptive effects of milk kefir (MK) on periodontitis in rats. Micro-Raman spectroscopy was performed on MK at different fermentation times to verify the presence of Lactobacillus kefiri. From these results, Wistar rats were divided into the following groups: C (Control); EP (experimental periodontitis); K1 (animals that received MK with one day of fermentation); K1+EP; K4 (animals without EP using MK with four days of fermentation) and K4+EP. MK was administered 28 days before EP induction and during the disease development period (11 days). On day 28, in the EP groups, periodontitis was induced. The animals were euthanized on day 39. The hemimaxillae were removed and the following parameters were evaluated: micro-Raman analysis of the presence of inflammation; histomorphometric analysis to quantify alveolar bone loss and immunohistochemistry for IL-6, TNF-α, IL-Iβ and IL-10 in the periodontal ligament. Micro-Raman analysis showed that four days fermentation MK has a higher intensity spectrum of L. kefiri. Furthermore, the administration of this probiotic reduced the intensity of the inflammation spectrum when compared to one day fermentation MK. It was observed that the animals from the K4+EP group showed significant reduction of alveolar bone loss, as well as a lower IL-6, TNF-α and IL-Iβ immunoexpression and a higher IL-10 immunoexpression, when compared to EP groups. We conclude that MK has anti-inflammatory and antiresorptive effects on periodontitis in rats and that these effects are fermentation time dependent.

Effects of curcumin gel on osteoclastogenic bone markers in experimental periodontitis and alveolar bone loss in wistar rats

Background/purposeCurcumin has anti-inflammatory impacts and was suggested as an inflammatory disease therapy. This study aimed to investigate the implications of curcumin gel on experimental periodontitis (EPD) and alveolar bone loss in rats. Materials and methodsIn this study, twenty-four male Wistar rats were divided equally into four groups: negative control (with no EPD); positive control (EPD induced around lower centrals without treatment); control-treated group: EPD treated with chlorhexidine; and test EPD group treated with curcumin. After 30 days, the serum concentrations of RANKL and IL-1β were measured via ELISA. All animals were sacrificed, and mandibular central incisors with the periodontium were removed. The lingual probing depth and radiographical alveolar bone loss were measured, then samples processed for routine preparation of H&E stained sections and histologically assessed for counting inflammatory cells, osteoclasts, and PDL width. ResultsA significant decrease in the inflammatory cells infiltration, probing depth, and osteoclast numbers with the improvement of PDL associated with a reduction in RANKL and IL-1β serum concentration were seen in both EPD treated groups. ConclusionCurcumin is as effective as chlorhexidine in treating experimental periodontitis in rats. It was demonstrated to stop bone destruction related to periodontitis by regulating the RANKL and IL-1β markers level in the blood.

Non-surgical Periodontal Treatment Restored the Gut Microbiota and Intestinal Barrier in Apolipoprotein E-/- Mice With Periodontitis.

Periodontitis has been associated with a variety of systematic diseases via affecting gut microbiota. However, the influence of periodontal treatment on intestinal microbiota is not known. Hyperlipidemia can significantly alter gut microbiota structure. It is proposed that the presence of hyperlipidemia can influence the impact of periodontitis on microbiota. This study was conducted to explore the influence of periodontitis and periodontal treatment on the gut microbiota on the basis of hyperlipidemia. Apolipoprotein E−/−(ApoE−/−) mice were ligatured to induced periodontitis and non-surgical periodontal treatment was performed for half of them after 4 weeks of ligation. Microbiota communities in the feces collected at 4, 5, 8 weeks after ligation were investigated using next-generation sequencing of 16S rDNA. Bone loss at periodontitis sites were analyzed using micro-computed tomography (Micro-CT). Morphology and mucosal architecture injury of ileum tissue were observed with hematoxylin-eosin staining. The serum lipid levels were assayed. The results showed that β-diversity index in experimental periodontitis group was differed significantly from that of the control group. Significant differences were found in β-diversity between the non-surgical periodontal treatment group and the ligation group. The samples of the non-surgical periodontal treatment group and the control group were clustered together 4 weeks after periodontal treatment. Intestinal villus height and ratio of villus height to crypt depth was found decreased after ligation and restored after non-surgical periodontal treatment. Non-surgical periodontal treatment induced the colonization and prosper of butyrate-producing bacteria Eubacterium, which was absent/not present in the ligation group. We confirmed that periodontitis led to gut microbiota dysbiosis in mice with hyperlipidemia. Non-surgical periodontal treatment had the trend to normalize the gut microbiota and improved the intestinal mucosal barrier impaired by periodontitis in apoE−/− mice.

A biochemical and immunohistochemical study of the effects of caffeic acid phenethyl ester on alveolar bone loss and oxidative stress in diabetic rats with experimental periodontitis

ABSTRACT Caffeic acid phenethyl ester (CAPE) is used as a therapeutic agent to prevent bone loss. We determined the effects of systemically administered CAPE on alveolar bone loss and oxidative stress in diabetic rats with experimental periodontitis. Forty male rats were divided into four equal groups: control, experimental periodontitis (EP), EP-diabetes mellitus (EP-DM) and EP-DM-CAPE. DM was induced by streptozotocin, then lipopolysaccharide was injected to induce periodontitis. CAPE was administered to the EP-DM-CAPE group daily for 15 days. Then, serum samples were taken and the rats were sacrificed for histological analyses. Serum interleukin (IL-1β) and oxidative stress also were evaluated. Alveolar bone loss was assessed histomorphometrically. Alveolar bone loss and IL-1β levels were significantly less in the EP-DM-CAPE and EP groups compared to the EP-DM group. Oxidative stress was significantly less in the EP-DM-CAPE group compared to the EP and EP-DM groups. Receptor activator of nuclear factor kappa-B ligand (RANKL) levels were significantly higher in the EP-DM group compared to the disease groups. CAPE significantly reduced RANKL levels in the EP-DM-CAPE group compared to the EP-DM group. We found that CAPE treatment significantly inhibited DM induced oxidative stress and RANKL induced osteoclastogenesis and alveolar bone loss in diabetic rats with periodontitis.

Electroacupuncture increases immunoexpression of CB1 and CB2 receptors in experimental model of inflammatory bone loss.

This study evaluated the participation of CB1 and CB2 receptors in the antiresorptive effect of electroacupuncture (EA) on an experimental model of inflammatory bone loss in rats. 30 rats were divided into five groups: C (control); EP (experimental periodontitis); EA (C+ EA); EP-EA (EP+ EA in the acupoints LI4, LG11, ST36, ST44); EP - EA-sham (EP+ EA in sham acupoints). For the EP groups, a ligature was placed around the right mandibular first molars at day 1. Sessions of EA or EA-sham were assigned every other day. Animals were euthanized at day 11. Histometric analysis was performed to evaluate the percentage of bone area in the furcation area. Immunolabeling patterns in the periodontal tissues and immunofluorescent staining in the trigeminal ganglia and in the trigeminal spinal tract for CB1 and CB2 receptors were performed. It was observed increased bone loss in the furcation in the EP and EP-EA-sham groups, in comparison to the other groups (p < 0.05). Enhanced CB2 immunolabeling was observed in the periodontal tissues in the EP-EA group, when compared to the EP and EP-EA-sham groups (p < 0.05). Increased CB1 immunofluorescent staining was observed in the neural tissues in the EA treated group in comparison with the other groups (p < 0.05), while no expression of CB2 was observed in those regions. Our study showed that in the presence of inflammatory bone disease, EA treatment reduced bone erosion and increased the immunoexpression of CB1 in the neural tissues and CB2 in the periodontal tissues.

Protective effects of crocin on biochemistry and histopathology of experimental periodontitis in rats

ABSTRACTWe investigated the effectiveness of crocin for preventing oxidative damage in experimentally produced periodontitis. We used three groups of 10 female Wistar rats divided into: control (C); experimental periodontitis (EP), experimental periodontitis + crocin (Cr-EP). Malondialdehyde (MDA), glutathione (GSH), total antioxidant status (TAS), total oxidant status (TOS) and superoxide dismutase (SOD) and catalase (CAT) enzyme activities were measured. We examined histopathology and inflammatory cell infiltration in gingiva and periodontal ligament. MDA and TOS levels, and SOD and CAT activities increased significantly in rats with induced periodontitis compared to the control group, while GSH and TAS levels were decreased significantly compared to the control group. Histopathologic examination revealed inflammatory cell infiltration in gingiva epithelium and subepithelial connective tissue in the EP group. Histological damage was reduced significantly after crocin treatment compared to the EP group. Crocin supplementation may help reduce oxidative damage to periodontal tissues.

Histopathological and biochemical evaluation of the effect of Paeoniflorin on the periodontium during and after periodontitis formation in rats

ObjectivesAppraise the effect of systemic Paeoniflorin (Pae) application on the periodontium during and after induction of experimental periodontitis in the presence of ligature and after its removal. DesignSeventy male Wistar rats were separated into seven equal groups. The first group was reserved as healthy control group (Group 1: no periodontitis, no medication) and experimental periodontitis was induced with ligature in the remaining rats. In experimental periodontitis groups, Pae or saline was administered systemically in three differet periods; during the experimental periodontitis induction (period 1), after experimental periodontitis induction which ligature removed (period 2) or ligature kept in position (period 3). Only, one of the groups acted as the control periodontitis group and received no treatment. Experimental periodontitis groups were as follows; Group 2: medication in period 1, Group 3: periodontitis and no medication, Group 4: medication in period 2, Group 5: saline application in period 2, Group 6: medication in period 3, Group 7: saline application in period 3. Matrix metalloproteinases-9 (MMP-9) levels and interleukin-10 (IL-10) levels were detected biochemically and histomorphometric analyses were performed. These analyses included measurements of the area of alveolar bone, the level of alveolar bone, and attachment loss. ResultsArea of alveolar bone and IL-10 levels were higher in the Pae-administered groups; level of alveolar bone, attachment loss, and MMP-9 levels were correspondingly lower (P < 0.05). The beneficial effects at histomorphometrical and biochemical levels of Pae were the strongest in the rats that were administered Pae after the removal of ligature. ConclusionsSystemically administered Pae had a positive effect on the healing of periodontal tissues. Pae can be used as a new therapeutic agent for periodontal diseases, but microbiology-based studies and more extensive biochemistry-based experimental and clinical studies are needed to address this possibility.

Influence of adjuvant therapy with green tea extract in the treatment of experimental periodontitis

AimThis study evaluated the effects of topical green tea extract solution (GTE) as adjuvant therapy to mechanical debridement for the treatment of experimental periodontitis (EP). Material and methodsWe used 120 male rats (Rattus norvegicus albinus – Wistar), divided into the following four groups: NEP (sham) (n = 30): no experimental periodontitis (NEP), only simulation of EP by installation and removal of a ligature; EP (n = 30): EP induction by ligature; SRP (n = 30): EP, scaling and root planing (SRP), and irrigation with physiological saline solution; SRP/GT (n = 30): EP, SRP, and irrigation with GTE. Histologic analysis and immunohistochemistry were performed for detection of interleukin (IL)1ß, tumor necrosis factor-alpha (TNF-α), IL-10, and anti-tartrate resistant acid phosphatase (TRAP) in the furcation area. The percentage of bone in the furcation (PBF) was considered the primary variable and evaluated at 14, 22, and 37 days. The data from the histological analysis and the IL- 1B, TNF- A, and IL-10 were submitted to a Kruskal-Wallis variance test and Dunn’s posttest (p ≤ 0.05). The histometric data and TRAP were submitted to analysis of variance (ANOVA) and Tukey’s posttest (p ≤ 0.05). ResultsThe SRP/GT group showed lower inflammatory process, lower immunolabeling pattern of IL-1ß and TNF-α, and greater immunolabeling pattern of IL-10 compared with the EP and SRP groups at 22 days. Fewer TRAP-positive multinucleated osteoclasts were observed in all periods in the SRP/GT group (5.22 ± 0.65; 7.33 ± 0.80; 8.55 ± 1.15) compared with the SRP group (30.67 ± 8.55; 13.22 ± 0.77; 13.87 ± 0.77). Higher PBF was observed in all periods in the SRP/GT group (74.65 ± 7.14; 76.61 ± 5.36; 79.24 ± 3.75) compared with the SRP group (61.60 ± 9.48; 54.84 ± 9.06; 53.25 ± 9.66). ConclusionGTE adjuvant to SRP reduced inflammation, osteoclastic activity, and alveolar bone loss in EP.