Heat-killed Limosilactobacillus reuteri ATCC PTA 6475 prevents bone loss in ovariectomized mice: A preliminary study.

Osteoporosis is an important health problem that occurs due to an imbalance between bone formation and resorption. Hormonal deficiency post-menopause is a significant risk factor. The probiotic Limosilactobacillus reuteri has been reported to prevent ovariectomy (Ovx)-induced bone loss in mice and reduce bone loss in postmenopausal women. Despite the numerous health benefits of probiotics, as they are live bacteria, the administration is not risk-free for certain groups (e.g., neonates and immunosuppressed patients). We evaluated the effects of L. reuteri (ATCC PTA 6475) and its heat-killed (postbiotic) form on Ovx-induced bone loss. Adult female mice (BALB/c) were randomly divided into four groups: group C-control (sham); group OVX-C-Ovx; group OVX-POS-Ovx + heat-killed probiotic; group OVX-PRO-Ovx + probiotic. L. reuteri or the postbiotic was administered to the groups (1.3x109 CFU/day) by gavage. Bacterial morphology after heat treatment was accessed by scanning electron microscopy (SEM). The treatment started one week after Ovx and lasted 28 days (4 weeks). The animals were euthanized at the end of the treatment period. Bone microarchitecture and ileum Occludin and pro-inflammatory cytokines gene expression were evaluated by computed microtomography and qPCR techniques, respectively. The Ovx groups had lower percentage of bone volume (BV/TV) and number of bone trabeculae as well as greater total porosity compared to the control group. Treatment with live and heat-killed L. reuteri resulted in higher BV/TV and trabecular thickness than the Ovx group. The heat treatment caused some cell surface disruptions, but its structure resembled that of the live probiotic in SEM analysis. There were no statistical differences in Occludin, Il-6 and Tnf-α gene expression. Both viable and heat-killed L. reuteri prevented bone loss on ovariectomized mice, independently of gut Occludin and intestinal Il-6 and Tnf-α gene expression.

Efeitos de probióticos e posbióticos na saúde óssea / Effects of probiotics and postbiotics in bone health

O envelhecimento da população tem sido acompanhado por um aumento significativo nas doenças crônicas, com destaque para a osteoporose. A busca por tratamentos alternativos tem levado ao estudo dos probióticos para prevenção e tratamento da perda óssea pós-menopáusica, com resultados encorajadores. Embora os benefícios dos probióticos sejam numerosos, eles são bactérias vivas e a administração de organismos vivos não é isenta de riscos. Os posbióticos são probióticos inativados ou seus produtos, e poucos são os estudos que avaliam seus efeitos ósseos. Nós revisamos a literatura sobre probióticos e posbióticos na saúde óssea e avaliamos os efeitos de Limosilactobacillus reuteri 6475 viável e inativado por calor em camundongos ovariectomizados. Mecanismos de ação semelhantes, como modulação da expressão de citocinas e ativação de sistemas de sinalização celular, são observados em probióticos e posbióticos, e os últimos têm vantagens como maior estabilidade e facilidade de incorporação em alimentos, embora seus efeitos a longo prazo, estabilidade e modo de ação ainda precisem ser estudados. Para que estas terapias sejam validadas clinicamente, é fundamental padronizar metodologias, aumentar o tamanho das amostras, realizar estudos randomizados e cegos, e definir detalhes como cepa, dose e duração do tratamento. Em um estudo in vivo, avaliamos os efeitos de L. reuteri (ATCC PTA 6475), e sua forma inativada (heat-killed) na perda óssea induzida por ovariectomia (ovx). Camundongos adultos, fêmeas, foram divididos aleatoriamente em quatro grupos: controle (sham); Ovx; Ovx + posbiótico; Ovx + probiótico. L. reuteri foi administrado aos grupos (109 UFC/dia) por gavagem. O tratamento se iniciou uma semana após a ovx e teve duração de 28 dias. Na análise por microscopia eletrônica de varredura, o probiótico manteve sua estrutura intacta, e no posbiótico foram observados alguns rompimentos na superfície celular. Foi avaliada a microarquitetura de fêmur, utilizando microtomografia computadorizada. Análise de expressão gênica em íleo foi feita para avaliar junções intercelulares intestinais e citocinas pró-inflamatórias, por meio dos marcadores Ocludina, Tnf-α e Il6. Os dados foram submetidos ao teste estatístico mais conveniente (α = 0,05). Os grupos Ovx apresentaram menor porcentagem de volume ósseo (BV/TV), menor número de trabéculas ósseas e maior porosidade total, em comparação ao grupo controle, porém os grupos que receberam L. reuteri apresentaram maior BV/TV quando comparados ao grupo Ovx. O tratamento com L. reuteri em suas duas formas levou à maior espessura trabecular, quando comparados ao controle e ao grupo Ovx. Todos apresentaram semelhança na expressão gênica da Ocludina, Tnf-α e Il-6 em intestino. Ambas as formas, viável e inativada por calor, preveniram a perda óssea induzida por depleção de estrógeno (AU)

The aging of the population has been accompanied by a significant increase in chronic diseases, with osteoporosis standing out. The search for alternative treatments has led to the study of probiotics for the prevention and treatment of postmenopausal bone loss, with encouraging results. Although the benefits of probiotics are numerous, they are live bacteria, and the administration of live organisms is not risk-free. Postbiotics are inactivated probiotics or their products, and few studies have evaluated their bone effects. We reviewed the literature on probiotics and postbiotics in bone health and assessed the effects of both viable and heat-killed Limosilactobacillus reuteri 6475 in ovariectomized mice. Similar mechanisms of action, such as the modulation of cytokine expression and activation of cellular signaling pathways, are observed in probiotics and postbiotics, and the latter have advantages such as greater stability and ease of incorporation into food, although their long-term effects, stability, and mode of action still need to be studied. To clinically validate these therapies, it is crucial to standardize methodologies, increase sample sizes, conduct randomized and blinded studies, and define details such as strain, dosage, and treatment duration. In an in vivo study, we evaluated the effects of L. reuteri (ATCC PTA 6475) and its heat-killed form on ovariectomy (ovx)-induced bone loss. Adult female mice were randomly divided into four groups: control (sham); OVX; OVX + postbiotic; OVX + probiotic. L. reuteri was administered to the groups (109 CFU/day) by gavage. Treatment began one week after ovx and lasted for 28 days. Scanning electron microscopy analysis showed that the probiotic maintained its intact structure, while some cell surface disruptions were observed in the postbiotic. Femur microarchitecture was evaluated using computerized microtomography. Gene expression analysis in the ileum was performed to assess intestinal intercellular junctions and pro-inflammatory cytokines, using markers Ocludin, Tnf-α, and Il-6. The data were subjected to the most appropriate statistical test (α = 0.05). The Ovx groups showed a lower percentage of bone volume (BV/TV), a lower number of trabecular bones, and greater total porosity compared to the control group. However, the groups that received L. reuteri showed higher BV/TV compared to the Ovx group. Treatment with both forms of L. reuteri led to greater trabecular thickness compared to the control and Ovx groups. All groups exhibited similarity in the gene expression of Ocludin, Tnf-α, and Il-6 in the intestine. Both viable and heatkilled forms prevented estrogen depletion-induced bone loss (AU)

Oral Lymphoepithelial Cyst: A Collaborative Clinicopathologic Study of 132 Cases from Brazil.

The oral lymphoepithelial cyst (OLC) is an uncommon lesion whose pathogenesis remains poorly understood. The aim of this study was to report the clinicopathologic features of the OLCs and to verify a possible association between OLCs and subgemmal neurogenous plaque (SNP) in the posterior lateral region of the tongue. A retrospective descriptive cross-sectional study was carried out. A total of 106,282 biopsy records of oral and maxillofacial lesions from six oral pathology services in Brazil were analyzed. All cases of OLCs were reviewed, and clinical and histopathological data were collected. Immunohistochemical reactions for S-100 protein were performed to confirm the diagnosis of SNP. Among all lesions, there were 132 (0.11%) cases of OLCs. The series comprised 83 females (62.9%) and 49 males (37.1%), with a 1.7:1 female-to-male ratio and a mean age of 45.8 ± 17.7 years. Most cases involved the tongue (n = 80; 62.0%) and presented clinically as asymptomatic papules or nodules with a yellow or whitish color. Microscopically, most of the cysts were entirely lined by parakeratinized stratified epithelium (n = 89; 67.4%) and filled with desquamated cells, keratin debris, amorphous eosinophilic material, and inflammatory cells in varying amounts. Connection with the epithelium of oral mucosa was observed in 18 cases (13.6%). SNP was found in 9/80 (11.2%) cases involving the tongue. The clinical and demographic features of OLCs were similar to those described in previous studies. Overall, this lesion has a predilection for the posterior region of the tongue of female adults. Clinicians must include the OLC in the differential diagnosis of yellow/white papules and nodules of the oral cavity.

Vascular leiomyoma in the oral cavity - Report of two cases.

Vascular leiomyomas (VL) are benign lesions of perivascular origin. We report two new cases and discuss their clinical, histological and immunohistochemical characteristics, in order to facilitate the diagnosis and treatment of such lesions. The patients, both male, presented asymptomatic nodules located in the bottom of the labial sulcus and buccal mucosa. In the second case, color doppler ultrasonography was performed, which showed no change in blood flow. After excisional biopsies, a limited lesion was observed histologically, with multiple tortuous vessels of varying sizes and calibers, and among them, spindle cells bundles, positive for smooth muscle actin. Oral VLs have clinical features similar to those of other more common lesions, making preoperative diagnosis difficult. Imaging examination, such as color doppler ultrasonography, may help in diagnosis. In general, excisional biopsy is performed, due to the ease of removal of the lesion during surgery. The treatment of choice is the complete excision of the lesion, which has an excellent prognosis and a low rate of recurrence. Key words:Vascular leiomyoma, spindle cells, thrombus, Doppler.

Granulomas piogênicos orais: prevalência, classificação e estudo imunohistoquímico / Oral pyogenic granulomas: prevalence, classification and immunohistochemical study

Granuloma piogênico (GP) é uma lesão de origem inflamatória que ocorre frequentemente em pele e cavidade oral. Existem dois subtipos histológicos: o tipo não lobular (GPNL), que é caracterizado por proliferação vascular semelhante a tecido de granulação, sem padrão de organização; e o tipo lobular (GPL) que se caracteriza pela organização dos vasos em agregados lobulares, separados por feixes de tecido conjuntivo. O objetivo deste estudo foi revisar todos os casos de granulomas piogênicos do nosso serviço de patologia bucal, a partir do ano 2000, reclassificar e correlacionar as características clínicas, microscópicas e imunohistoquímicas com os subtipos da lesão. No levantamento foram encontrados no arquivo 197 casos diagnosticados como granuloma piogênico e hemangioma lobular capilar. Após revisão das lâminas, 9 casos foram reclassificados, e 19 foram excluídos, restando 169 casos, sendo 62 de GPL e 107 de GPNL. Foram coletados ainda dados como sexo, idade, local da lesão, tipo de nódulo, ocorrência de trauma prévio e hipótese diagnóstica clínica. Reações imuno-histoquímicas (GLUT-1, CD34, D2-40, AML e Mast cell) de 22 casos, sendo 11 lobulados e 11 não lobulados. A média de idade de acometimento foi de 38,59 ± 16,96 anos, com 55,62% dos casos ocorrendo em pacientes do sexo feminino (10,12% durante gravidez), com maior acometimento em gengiva (39,64%), 44,97% dos nódulos eram do tipo pediculado e 13,02% relataram trauma mecânico prévio. O GPNL ocorre mais em gengiva, enquanto GPL acomete mais lábio (p < 0,05). O número de microvasos (marcados por CD34), área positiva para AML e ocorrência de atrofia do epitélio são mais prevalentes em GPL (p < 0,05), enquanto o número de mastócitos não teve diferença estatística entre os tipos histológicos. A marcação para GLUT-1 foi negativa em todos os casos. Em conclusão, o GP corresponde a 2,25% das lesões do nosso serviço de patologia, e a maioria é do tipo não lobular. Ocorre mais em indivíduos do sexo feminino, tem predileção por sítios gengivais, e 44% dos nódulos são do tipo pediculado. O GPL ocorre em indivíduos mais jovens do que o GPNL, e em lábios; na maioria das vezes possui epitélio atrófico, não sofre processo de maturação e possui maior vascularização(AU)

Pyogenic granuloma (GP) is an inflammatory lesion that occurs frequently in the skin and oral cavity. There are two histological subtypes: the non-lobular type (NLCH), which is characterized by vascular proliferation similar to granulation tissue, without organization pattern; and lobular capillary hemangioma (LCH) characterized by the organization of vessels in lobular aggregates, separated by bundles of connective tissue. The purpose of this study was to review all cases of pyogenic granulomas of our oral pathology service, from the year 2000, to classify and correlate the clinical, microscopic and immunohistochemical characteristics with the subtypes of the lesion. In the survey, 197 cases diagnosed as pyogenic granuloma and lobular capillary hemangioma were found in our files. After review, 9 cases were reclassified, and 19 were excluded, remaining 169 cases, being 62 LCH and 107 NLCH. Data such as sex, age, site of lesion, type of nodule, previous trauma and clinical diagnostic hypothesis were also collected. Immunohistochemical reactions (GLUT-1, CD34, D2- 40, SMA and Mast cell) of 24 cases, 11 LCH and 11 NLCH. Mean age was 38.59 ± 16.96 years, with 55.62% of cases occurring in female patients (10.12% during pregnancy), with a greater involvement in gingiva (39.64%), 44.97% of the nodules were pedunculated and 13.02% reported previous mechanical trauma. The NLCH occurs more in gingiva, while LCH affects more lips (p < 0,05). The number of microvessels (CD34 positive), SMA positive staining area and occurrence of epithelial atrophy are more prevalent in LCH (p < 0,05), while the number of mast cells had no statistical difference between histological types. In conclusion, PG corresponds to 2.25% of the lesions of our pathology service and most are NLCH. It occurs more in females, has predilection for gingival sites, and 44% of nodules are pedunculated. LCH occurs in younger individuals than the NLCH, and in the lips; most of the time it has atrophic epithelium, it does not undergo maturation process, and has greater vascularization(AU)