RESUMO
This study evaluated the biocompatibility, bioactivity, porosity, and sealer/dentin interface of Sealer Plus BC (SP), Bio-C Sealer (BIOC), TotalFill BC Sealer (TF), and AH Plus (AHP). Dentin tubes filled with the sealers and empty tubes (control group) were implanted in the subcutaneous tissue of rats for different periods (n = 6 per group/period). Number of inflammatory cells (ICs), capsule thickness, von Kossa reaction, interleukin-6 (IL-6) and osteocalcin (OCN) were evaluated. Porosity and voids in the interface dentin/sealers were assessed by micro-computed tomography. The data were submitted to ANOVA/Tukey's tests (α = 0.05). Greater capsule thickness, ICs and IL-6 immunolabeling cells were observed in AHP. No significant difference in thickness of capsule, ICs, and IL-6- immunolabeling cells was detected between SP and TF, in all periods, and after 30 and 60 days between all groups. At 60 days all groups had reduction in capsule thickness, ICs and IL-6 immunolabeling cells. Von Kossa-positive and birefringent structures were observed in the capsules around the sealers. BIOC, SP, and TF exhibited OCN-immunolabeling cells. All sealers had porosity values below 5%, besides low and similar interface voids. BIOC, SP and TF are biocompatible, bioactive, and have low porosity and voids. The dentin-tube model used is an alternative for evaluating bioceramic materials.
Assuntos
Materiais Biocompatíveis , Dentina , Teste de Materiais , Animais , Porosidade , Dentina/química , Dentina/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Ratos , Cerâmica/química , Interleucina-6/metabolismo , Microtomografia por Raio-X , Masculino , Ratos Wistar , Selantes de Fossas e Fissuras/químicaRESUMO
Although SARS-CoV-2 induces mucin hypersecretion in the respiratory tract, hyposalivation/xerostomia has been reported by COVID-19 patients. We evaluate the submandibular gland (SMGs) pathogenesis in SARS-CoV-2-infected K18-hACE2 mice, focusing on the impact of infection on the mucin production and structural integrity of acini, ductal system, myoepithelial cells (MECs) and telocytes. The spike protein, the nucleocapsid protein, hACE2, actin, EGF, TNF-α and IL-1ß were detected by immunofluorescence, and the Egfr and Muc5b expression was evaluated. In the infected animals, significant acinar hypertrophy was observed in contrast to ductal atrophy. Nucleocapsid proteins and/or viral particles were detected in the SMG cells, mainly in the nuclear membrane-derived vesicles, confirming the nuclear role in the viral formation. The acinar cells showed intense TNF-α and IL-1ß immunoexpression, and the EGF-EGFR signaling increased, together with Muc5b upregulation. This finding explains mucin hypersecretion and acinar hypertrophy, which compress the ducts. Dying MECs and actin reduction were also observed, indicating failure of contraction and acinar support, favoring acinar hypertrophy. Viral assembly was found in the dying telocytes, pointing to these intercommunicating cells as viral transmitters in SMGs. Therefore, EGF-EGFR-induced mucin hypersecretion was triggered by SARS-CoV-2 in acinar cells, likely mediated by cytokines. The damage to telocytes and MECs may have favored the acinar hypertrophy, leading to ductal obstruction, explaining xerostomia in COVID-19 patients. Thus, acinar cells, telocytes and MECs may be viral targets, which favor replication and cell-to-cell viral transmission in the SMG, corroborating the high viral load in saliva of infected individuals.
Assuntos
COVID-19 , Receptores ErbB , SARS-CoV-2 , Glândula Submandibular , Xerostomia , COVID-19/patologia , COVID-19/virologia , COVID-19/metabolismo , Animais , Glândula Submandibular/virologia , Glândula Submandibular/patologia , Glândula Submandibular/metabolismo , SARS-CoV-2/fisiologia , Camundongos , Xerostomia/etiologia , Xerostomia/patologia , Xerostomia/virologia , Xerostomia/metabolismo , Receptores ErbB/metabolismo , Humanos , Enzima de Conversão de Angiotensina 2/metabolismo , Mucina-5B/metabolismo , Células Acinares/patologia , Células Acinares/metabolismo , Células Acinares/virologia , Interleucina-1beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Modelos Animais de DoençasRESUMO
This study aimed to evaluate the osteogenic potential of hydroxyapatite (HA), Alginate (Alg), and Gelatine (Gel) composite in a critical-size defect model in rats. Twenty-four male rats were divided into three groups: a negative control with no treatment (Control group), a positive control treated with deproteinized bovine bone mineral (DBBM group), and the experimental group treated with the new HA-Alg-Gel composite (HA-Alg-Gel group). A critical size defect (8.5mm) was made in the rat's calvaria, and the bone formation was evaluated by in vivo microcomputed tomography analysis (µCT) after 1, 15, 45, and 90 days. After 90 days, the animals were euthanized and histological and histomorphometric analyses were performed. A higher proportion of mineralized tissue/biomaterial was observed in the DBBM group when compared to the HA-Alg-Gel and Control groups in the µCT analysis during all analysis periods. However, no differences were observed in the mineralized tissue/biomaterial proportion observed on day 1 (immediate postoperative) in comparison to later periods of analysis in all groups. In the histomorphometric analysis, the HA-Alg-Gel and Control groups showed higher bone formation than the DBBM group. Moreover, in histological analysis, five samples of the HA-Alg-Gal group exhibited formed bone spicules adjacent to the graft granules against only two of eight samples in the DBBM group. Both graft materials ensured the maintenance of defect bone thickness, while a tissue thickness reduction was observed in the control group. In conclusion, this study demonstrated the osteoconductive potential of HA-Alg-Gel bone graft by supporting new bone formation around its particles.
Assuntos
Alginatos , Regeneração Óssea , Durapatita , Gelatina , Crânio , Microtomografia por Raio-X , Animais , Regeneração Óssea/efeitos dos fármacos , Durapatita/farmacologia , Crânio/cirurgia , Crânio/diagnóstico por imagem , Ratos , Masculino , Materiais Biocompatíveis , Ácido Glucurônico , Ratos Wistar , Ácidos Hexurônicos , Osteogênese/efeitos dos fármacos , Substitutos ÓsseosRESUMO
OBJECTIVE: This study assessed the impact of an anti-sclerostin monoclonal antibody (Scl-Ab)-based osteoporosis drug on the post-extraction alveolar repair of ovariectomized rats. DESIGN: Fifteen female rats were randomly distributed into three groups: CTR (healthy animals), OST (osteoporosis induced by ovariectomy), and OST+Scl-Ab (osteoporosis induction followed by Scl-Ab treatment). Ovariectomy or sham surgery was performed 30 days before baseline, and Scl-Ab or a vehicle was administered accordingly in the groups. After seven days, all rats underwent the first lower molar extraction and were euthanized 15 days later. Computed microtomography, histological analysis, and collagen content measurement were performed on post-extraction sockets and intact mandibular and maxillary bone areas. RESULTS: Microtomographic analyses of the sockets and mandibles did not reveal significant differences between groups on bone morphometric parameters (p > 0.05), while maxillary bone analyses resulted in better maintenance of bone architecture in OST+Scl-Ab, compared to OST (p < 0.05). Descriptive histological analysis and polarization microscopy indicated better post-extraction socket repair characteristics and collagen content in OST+Scl-Ab compared to OST (p < 0.05). CONCLUSIONS: Scl-Ab-based medication did not accelerate alveolar bone formation but exhibited better post-extraction repair characteristics, and collagen content compared to ovariectomized animals only.
Assuntos
Proteínas Morfogenéticas Ósseas , Osteoporose , Ratos , Feminino , Animais , Ratos Sprague-Dawley , Marcadores Genéticos , Anticorpos Monoclonais/farmacologia , ColágenoRESUMO
AIM: To evaluate the inflammatory reaction and the ability to induce mineralization activity of a new repair material, NeoPUTTY (NPutty; NuSmile, USA), in comparison with Bio-C Repair (BC; Angelus, Brazil) and MTA Repair HP (MTA HP; Angelus, Brazil). METHODOLOGY: Polyethylene tubes were filled with materials or kept empty (control group, CG) and implanted in subcutaneous tissue of rats for 7, 15, 30, and 60 days (n = 6/group). Capsule thickness, number of inflammatory cells (ICs), fibroblasts, collagen content, and von Kossa analysis were performed. Unstained sections were evaluated under polarized light and by immunohistochemistry for osteocalcin (OCN). Data were submitted to two-way anova followed by Tukey's test (p ≤ .05), except for OCN. OCN data were submitted to Kruskal-Wallis and Dunn and Friedman post hoc tests followed by the Nemenyi test at a significance level of 5%. RESULTS: At 7, 15, and 30 days, thick capsules containing numerous ICs were seen around the materials. At 60 days, a moderate inflammatory reaction was observed for NPutty, BC while MTA HP presented thin capsules with moderate inflammatory cells. In all periods, NPutty specimens contained the highest values of ICs (p < .05). From 7 to 60 days, the number of ICs reduced significantly while an increase in the number of fibroblasts and birefringent collagen content was observed. At 7 and 15 days, no significant difference was observed in the immunoexpression of OCN (p > .05). At 30 and 60 days, NPutty showed the lowest values of OCN (p < .05). At 60 days, a similar immunoexpression was observed for BC and MTA HP (p > .05). In all time intervals, capsules around NPutty, BC, and MTA HP showed von Kossa-positive and birefringent structures. CONCLUSIONS: Despite the greater inflammatory reaction promoted by NeoPutty than BC and MTA HP, the reduction in the thickness of capsules, the increase in the number of fibroblasts, and the reduction in the number of ICs indicate that this bioceramic material is biocompatible Furthermore, NeoPutty presents the ability to induce mineralization activity.
Assuntos
Materiais Biocompatíveis , Bismuto , Compostos de Cálcio , Teste de Materiais , Silicatos , Animais , Silicatos/farmacologia , Compostos de Cálcio/farmacologia , Ratos , Materiais Biocompatíveis/farmacologia , Ratos Wistar , Óxidos/farmacologia , Combinação de Medicamentos , Masculino , Compostos de Alumínio/farmacologia , Cimentos Dentários/farmacologia , Fibroblastos/efeitos dos fármacos , Colágeno/metabolismoRESUMO
Intracanal medications are used in endodontic treatment due to their antibacterial activity and ability to induce the periapical repair. Among the intracanal medications, the Calen (CAL; SS. White, Brazil) is a calcium hydroxide-based medication that provides an alkaline pH and releases calcium, exerting an antimicrobial activity. Bio-C Temp (BIO; Angelus, Brazil), a ready-to-use bioceramic intracanal medication, was designed to stimulate the mineralized tissues formation. Here, we investigated the bioactive potential of BIO in comparison to the CAL in the rat subcutaneous. Polyethylene tubes filled with medications, and empty tubes (control group, CG) were implanted in the subcutaneous tissue of rats. After 7, 15, 30 and 60 days, the blood was collected for calcium (Ca+2) and alkaline phosphatase (ALP) measurement, and the capsules around the implants were processed for morphological analyses. The data were submitted to two-way ANOVA and Tukey test (p < 0.05). At 7, 15 and 30 days, the ALP level was grater in BIO and CAL than in CG (p < 0.0001). At 7 and 15 days, greater Ca+2 level was seen in the serum of CAL samples. From 7 to 60 days, an increase in the number of fibroblasts, osteocalcin- and osteopontin-immunolabelled cells was observed in BIO and CAL groups (p < 0.0001). In all periods, BIO and CAL specimens showed von Kossa-positive structures. Moreover, ultrastructural analysis revealed globules of mineralization in the capsules around the BIO and CAL specimens. Thus Bio-C Temp caused an increase in the ALP, osteocalcin and osteopontin, which may have allowed the formation of calcite, suggesting bioactive potential.
Assuntos
Calcinose , Osteopontina , Animais , Ratos , Osteocalcina , Cálcio , Tela Subcutânea , AntibacterianosRESUMO
BACKGROUND: Paroxetine, a selective serotonin reuptake inhibitor (SSRI) antidepressant, has caused male sexual dysfunction; however, the paroxetine mechanisms of action in testes are still unclear. OBJECTIVES: Paroxetine serotonergic effects in testes were evaluated, focusing on steroidogenesis and the correlation between macrophages population and possible TNF-α-derived oxidative stress. We also verified whether the changes are reversible following treatment interruption. MATERIALS AND METHODS: Adult rats received paroxetine (PG35 and PG65) or tap water (CG) for 35 days. PG65 was maintained without treatment for 30 more days. Intratesticular testosterone (IT), nitrite, and malondialdehyde concentrations were measured. To confirm serotonergic and estrogenic effects, Htr1b and Esr1 expressions were analyzed. The daily sperm production (DSP), frequency of abnormal seminiferous tubules (ST), SC number, ST area, and Leydig cells nuclear area (LCnu) were evaluated. TUNEL+ germ cells, M1 (CD68+ ), and M2 (Perls+ ) macrophages were quantified. 17ß-HSD7, CYP19A1, NDRG2, oxytocin, TNF-α, and iNOS were evaluated by immunoreactions. Oxytocin and NDRG2 protein levels as well as Tnfa mRNA expression were also analyzed. RESULTS: The Htr1b downregulation in testes confirmed the paroxetine serotonergic effect. The testicular sections showed abnormal ST frequency, ST atrophy and reduction of DSP, LCnu, SC number and Perls+ macrophages. TUNEL+ germ cells and LC were associated with strong NDRG2 immunoexpression. Paroxetine reduced IT levels and 17ß-HSD7 immunoexpression in parallel to increased CYP19A1, oxytocin, TNF-α and iNOS. Esr1 and Tnfa overexpression and increased number of CD68+ macrophages were also observed together with high nitrite and malondialdehyde levels. Most parameters were not recovered in PG65. CONCLUSIONS: Paroxetine serotonergic effect impairs LC steroidogenesis, via aromatization, increasing estrogen/testosterone ratio, which in turn upregulate NDRG2, promoting apoptosis, and impairing sperm production. Serotonin-estrogen pathways may be responsible for M2/M1 polarization, Tnfa upregulation, and induction of oxidative stress. The unrecovered testicular changes after treatment discontinuation are due to persistent paroxetine serotonin/estrogen effects.
Assuntos
Paroxetina , Testículo , Masculino , Ratos , Animais , Testículo/metabolismo , Paroxetina/farmacologia , Paroxetina/metabolismo , Serotonina , Fator de Necrose Tumoral alfa/metabolismo , Ocitocina , Nitritos/metabolismo , Nitritos/farmacologia , Sêmen , Testosterona/farmacologia , Estrogênios/metabolismo , Macrófagos , Malondialdeído/metabolismo , Malondialdeído/farmacologiaRESUMO
Abstract This study aimed to evaluate the osteogenic potential of hydroxyapatite (HA), Alginate (Alg), and Gelatine (Gel) composite in a critical-size defect model in rats. Twenty-four male rats were divided into three groups: a negative control with no treatment (Control group), a positive control treated with deproteinized bovine bone mineral (DBBM group), and the experimental group treated with the new HA-Alg-Gel composite (HA-Alg-Gel group). A critical size defect (8.5mm) was made in the rat's calvaria, and the bone formation was evaluated by in vivo microcomputed tomography analysis (µCT) after 1, 15, 45, and 90 days. After 90 days, the animals were euthanized and histological and histomorphometric analyses were performed. A higher proportion of mineralized tissue/biomaterial was observed in the DBBM group when compared to the HA-Alg-Gel and Control groups in the µCT analysis during all analysis periods. However, no differences were observed in the mineralized tissue/biomaterial proportion observed on day 1 (immediate postoperative) in comparison to later periods of analysis in all groups. In the histomorphometric analysis, the HA-Alg-Gel and Control groups showed higher bone formation than the DBBM group. Moreover, in histological analysis, five samples of the HA-Alg-Gal group exhibited formed bone spicules adjacent to the graft granules against only two of eight samples in the DBBM group. Both graft materials ensured the maintenance of defect bone thickness, while a tissue thickness reduction was observed in the control group. In conclusion, this study demonstrated the osteoconductive potential of HA-Alg-Gel bone graft by supporting new bone formation around its particles.
Resumo Este estudo teve como objetivo avaliar o potencial osteogênico de um compósito de hidroxiapatita (HA), alginato (Alg) e gelatina (Gel) em um modelo de defeito de tamanho crítico em ratos. Vinte e quatro ratos machos foram divididos em três grupos: um controle negativo sem tratamento (grupo controle), um controle positivo tratado com osso bovino desproteinizado (grupo DBBM) e o grupo experimental tratado com o novo compósito HA-Alg-Gel (grupo HA-Alg-Gel). Um defeito de tamanho crítico (8,5mm) foi feito na calvária dos ratos, e a formação óssea foi avaliada por análise de microtomografia computadorizada in vivo (µCT) após 1, 15, 45 e 90 dias. Após 90 dias, os animais foram eutanasiados e análises histológicas e histomorfométricas foram realizadas. Uma maior proporção de tecido mineralizado/biomaterial foi observada no grupo DBBM quando comparado aos grupos HA-Alg-Gel e controle na análise de µCT durante todos os períodos de análise. Entretanto, não foram observadas diferenças na proporção tecido mineralizado/biomaterial no dia 1 (pós-operatório imediato) em relação aos períodos posteriores de análise em todos os grupos. Na análise histomorfométrica, os grupos HA-Alg-Gel e controle apresentaram maior formação óssea do que o grupo DBBM. Além disso, na análise histológica, cinco amostras do grupo HA-Alg-Gal exibiram espículas ósseas formadas adjacentes aos grânulos do enxerto contra apenas duas das oito amostras do grupo DBBM. Ambos os materiais de enxerto garantiram a manutenção da espessura óssea do defeito, enquanto uma redução da espessura do tecido foi observada no grupo controle. Em conclusão, este estudo demonstrou o potencial osteocondutor do enxerto ósseo de HA-Alg-Gel, promovendo a formação de osso novo ao redor das suas partículas.
RESUMO
BACKGROUND: Annexin A1 (ANXA1) and the NOD-like receptor family pyrin domain-containing protein 3 (NLRP3) inflammasome play important roles in bone remodeling. However, expression profiles of these factors in bone cells under diabetes mellitus (DM) and estrogen-deficient conditions are poorly understood. This study investigated the immunoexpression of ANXA1 and its formyl peptide receptor 2 (FPR2), as well as NLRP3 inflammasome mediators, during remodeling of the alveolar process in diabetic and estrogen-deficient rats. METHODS: Twenty adult female Wistar rats were divided into four groups (n = 5): Sham-operated (SHAM) and ovariectomized (OVX) rats received a vehicle solution, and SHAM and OVX rats were intraperitoneally administered 60 mg/kg/body weight (BW) of streptozotocin (STZ) to induce DM (SHAM-Di and OVX-Di groups). After 7 weeks, the rats were euthanized and their maxillae were fixed in phosphate-buffered 4% formaldehyde and embedded in paraffin. Sections were stained with hematoxylin/eosin (H&E) and picrosirius red or subjected to immunohistochemical detection of ANXA1, FPR2, NLRP3, interleukin-1ß (IL-1ß), and cyclooxygenase-2 (COX2). RESULTS: Estrogen deficiency and DM were associated with deleterious effects in bone tissue, as evidenced by a lower number of osteocytes and higher number of empty lacunae in the SHAM-Di and OVX-Di groups compared to the nondiabetic groups. Both diabetic groups showed a smaller vascular area and weaker collagen fiber birefringence intensity in alveolar bone tissue. A significantly higher number of ANXA1/FPR2-positive osteoblasts, osteocytes, and osteoclasts was accompanied by a significantly higher number of these cells immunolabeled for COX2, NLRP3, and IL-1ß in the diabetic and OVX groups, especially in both estrogen-deficient and diabetic rats. CONCLUSION: These results indicate a possible role for the ANXA1/FPR2 pathway as a fine-tuning/anti-inflammatory regulator to counterbalance exacerbated COX2/NLRP3/IL-1ß activation in bone cells during bone remodeling under estrogen deficiency and DM.
RESUMO
This study investigated whether osteocalcin (OCN) is present in osteoblast precursors and its relationship with initial phases of alveolar process formation. Samples of maxillae of 16-, 18-, and 20-day-old rat embryos (E16, E18, and E20, respectively), and 05-, 10-, and 15-day-old postnatal rats (P05, P10, and P15, respectively) were fixed and embedded in paraffin or araldite. Immunohistochemistry for osterix (Osx), alkaline phosphatase (ALP), and OCN detection was performed and the number of immunolabelled cells was computed. Non-decalcified sections were subjected to the von Kossa method combined with immunohistochemistry for Osx or OCN detection. For OCN immunolocalization, samples were fixed in 0.5% glutaraldehyde/2% formaldehyde and embedded in LR White resin. The highest number of ALP- and OCN-immunolabelled cells was observed in dental follicle of E16 specimens, mainly in basal portions of dental alveolus. In corresponding regions, osteoblasts in differentiation adjacent to von Kossa-positive bone matrix exhibited Osx and OCN immunoreactivity. Ultrastructural analysis revealed OCN immunoreactive particles inside osteoblast in differentiation, and in bone matrix associated with collagen fibrils and within matrix vesicles, at early stages of alveolar process formation. Our results indicate that OCN plays a role in osteoblast differentiation and may regulate calcium/phosphate precipitation during early mineralization of the alveolar process.