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.

Interação entre Lactobacillus reuteri e bactérias periodontopatogênicas: estudo in vitro e em modelo de invertebrado / Interaction of Lactobacillus reuteri and periodontopathogenic bacteria: an in vitro study and on invertebrate model

A doença periodontal, afecção crônica inflamatória multifatorial, está entre as principais doenças bucais que afetam a população mundial. Entre as bactérias associadas à periodontite, estão Fusobacterium nucleatum e Aggregactibacter actinomycetemcomitans. Novas terapias adjuntas ao tratamento convencional têm sido propostas para a doença periodontal, entre elas o uso de probióticos. Porém, seu uso não está isento de riscos, e uma alternativa para minimizá-los é inativar os microorganismos, mantendo suas propriedades benéficas, o que ocorre com os chamados paraprobióticos. Desse modo, são objetivos deste estudo avaliar os efeitos antimicrobianos de L. reuteri vivo, inativado pelo calor e seus produtos sobre F. nucleatum, A. actinomycetemcomitans e sobre as bactérias comensais, Streptococcus mitis e Streptococcus salivarius, além de estudar os efeitos da interação das preparações e periodontopatógenos em modelo de invertebrado. A atividade antimicrobiana in vitro foi avaliada associando-se as bactérias patogênicas ou comensais a L. reuteri vivo, inativado ou sobrenadante. Após interação, as bactérias foram cultivadas em meio seletivo para contagem de unidades formadoras de colônias (UFC). No estudo em Galleria mellonella, após a infecção com as bactérias patogênicas e as preparações de L. reuteri, foi avaliada a curva de sobrevivência e densidade hemocitária. Os dados foram analisados com o teste estatístico apropriado, ao nível de 5%. Após interação bacteriana in vitro, S. salivarius reduziu o número de UFC de L. reuteri, enquanto que não houve interferência das outras bactérias. O probiótico foi mais eficiente em reduzir o crescimento das bactérias periodontopatogênicas e comensais, exceto para F. nucleatum onde a preparação do sobrenadante foi melhor. In vivo, o sobrenadante foi mais eficiente em aumentar a sobrevivência das lagartas quando infectadas por F. nucleatum. Entretanto, quando infectadas por A. actinomycetemcomitans, nenhuma das preparações aumentou a sobrevivência. Da mesma maneira, nenhuma das preparações aumentaram o número de hemócitos das lagartas após infecção por F. nucleatum e A. actinomycetemcomitans, apesar de todas resultarem em redução na contagem de colônias das bactérias periodontopatogênicas. Dessa forma, concluiu-se que tanto o probiótico quanto os produtos dele derivados apresentaram efeitos antimicrobianos e aumentaram a sobrevivência de G. mellonella quando infectada por F. nucleatum (AU)

Periodontal disease, a chronic multifactorial inflammatory disease, is among the major oral diseases that affects the worldwide population. Among the bacteria associated with periodontitis are Fusobacterium nucleatum and Aggregactibacter actinomycetemcomitans. New therapies have been proposed for periodontal disease as adjunct to conventional treatment, including the use of probiotics. However, their use isn't risk-free and an alternative to that is the inactivation of the microorganisms, maintaining their beneficial properties, which occurs with the paraprobiotics. Thus, the objective of this study is to evaluate the antimicrobial effects of living and heat-killed L. reuteri, and its products on F. nucleatum, A. actinomycetemcomitans and on the commensal bacteria, Streptococcus mitis and Streptococcus salivarius, as well as to study the interaction of the preparations and periodontopathogens in an invertebrate model. In vitro antimicrobial activity was evaluated by associating the pathogenic or commensal bacteria to live, heat killed or L. reuteri supernatant. After interaction, the bacteria were cultured in a selective medium for colony-forming unit (CFU) count. In the study with Galleria mellonella, after infection with pathogenic bacteria and L. reuteri preparations, the survival curve and hemocyte density were evaluated. The data were analyzed with the appropriate statistical test at the 5% level. After bacterial interaction in vitro, S. salivarius reduced the number of CFU of L. reuteri, while there was no interference of the other bacteria. The probiotic was more efficient in reducing the growth of periodontopathogenic and commensal bacteria, except for F. nucleatum. In this case, the supernatant presented better results. In vivo, the supernatant was more efficient in increasing the larvae survival when infected by F. nucleatum. However, when infected by A. actinomycetemcomitans, none of the preparations increased the survival. Likewise, none of the preparations increased the number of hemocytes of the larvae after infection by F. nucleatum and A. actinomycetemcomitans, although all resulted in reduction in the CFU of the periodontopathogenic bacteria. Thus, it was concluded that the probiotic and the products derived therefrom presented antimicrobial effects and increased the survival of G. mellonella when infected by F. nucleatum.(AU)

Jaw osteosarcoma and pregnancy: a rare coexistence.

Osteosarcoma of the jaw represents less than 1% of all head and neck malignancies. This malignancy in pregnant women occurs in one per 1000 deliveries. We report a case of a 29-year-old woman, in the 33rd week of gestation, who presented with an expansive tumor destroying the maxillary alveolar bone, histologically composed of pleomorphic, round, spindle, or epithelioid cells and osteoid/chondroid matrix. Upon final diagnosis of osteosarcoma, the lesion was excised. To the best of our knowledge, only 10 cases of jaw osteosarcoma in pregnant women have been reported to date in the English language literature. The use of ancillary examinations, malignancy diagnosis, and cancer treatment can be challenging during pregnancy. Knowledge about jaw osteosarcoma in pregnancy can increase healthcare providers' awareness, avoid delays and misdiagnosis and potentially improve maternal and neonatal outcomes.

Jaw osteosarcoma and pregnancy: a rare coexistence

Osteosarcoma of the jaw represents less than 1% of all head and neck malignancies. This malignancy in pregnant women occurs in one per 1000 deliveries. We report a case of a 29-year-old woman, in the 33rd week of gestation, who presented with an expansive tumor destroying the maxillary alveolar bone, histologically composed of pleomorphic, round, spindle, or epithelioid cells and osteoid/chondroid matrix. Upon final diagnosis of osteosarcoma, the lesion was excised. To the best of our knowledge, only 10 cases of jaw osteosarcoma in pregnant women have been reported to date in the English language literature. The use of ancillary examinations, malignancy diagnosis, and cancer treatment can be challenging during pregnancy. Knowledge about jaw osteosarcoma in pregnancy can increase healthcare providers' awareness, avoid delays and misdiagnosis and potentially improve maternal and neonatal outcomes.

Interaction between Lactobacillus reuteri and periodontopathogenic bacteria using in vitro and in vivo (G. mellonella) approaches.

Periodontitis is a multifactorial inflammatory disease, and the major cause of tooth loss in adults. New therapies have been proposed for its treatment, including the use of probiotics such as Lactobacillus reuteri. The objective of this study was to evaluate the antimicrobial effects of L. reuteri: live, heat-killed and culture filtrate (cell-free supernatant), on periodontopathogenic bacteria (Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans) in vitro, as well as the in vivo survival curve, hemocyte density and microbial recovery using Galleria mellonella. For in vitro assays, all preparations reduced colony forming units of F. nucleatum, while only live L. reuteri reduced the growth of A. actinomycetemcomitans. All treatments reduced periodontopathogenic bacteria growth in vivo. The treatment with the supernatant increased the survival of larvae infected with F. nucleatum more than the treatment with live L. reuteri, and none of the treatments altered the survival of A. actinomycetemcomitans-infected larvae. In addition, the treatment with L. reuteri preparations did not alter the hemocyte count of F. nucleatum- and A. actinomycetemcomitans-infected larvae. This study demonstrated that L. reuteri preparations exerted antimicrobial effects and increased the survival of G. mellonella infected by F. nucleatum, although only live L. reuteri was able to reduce the growth of A. actinomycetemcomitans in vitro.

Galleria mellonella as an experimental model for studying periodontopathogens.

In the present study, Galleria mellonella was evaluated as a potential infection model for periodontal bacteria, more specifically, Porphyromonas gingivalis, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans. All the bacteria evaluated were pathogenic to G. mellonella, causing their death in a concentration-dependent manner, and a decrease in their hemocyte count. Moreover, it was possible to recover the bacteria from the larvae hemolymph and determine the colony-forming units per larvae. G. mellonella is an effective model that may help to better understand the host-microbe interactions in periodontics.

Interação entre Lactobacillus reuteri e bactérias periodontopatogênicas: estudo in vitro e em modelo de invertebrado / Interaction of Lactobacillus reuteri and periodontopathogenic bacteria: an in vitro study and on invertebrate model

A doença periodontal, afecção crônica inflamatória multifatorial, está entre as principais doenças bucais que afetam a população mundial. Entre as bactérias associadas à periodontite, estão Fusobacterium nucleatum e Aggregactibacter actinomycetemcomitans. Novas terapias adjuntas ao tratamento convencional têm sido propostas para a doença periodontal, entre elas o uso de probióticos. Porém, seu uso não está isento de riscos, e uma alternativa para minimizá-los é inativar os microorganismos, mantendo suas propriedades benéficas, o que ocorre com os chamados paraprobióticos. Desse modo, são objetivos deste estudo avaliar os efeitos antimicrobianos de L. reuteri vivo, inativado pelo calor e seus produtos sobre F. nucleatum, A. actinomycetemcomitans e sobre as bactérias comensais, Streptococcus mitis e Streptococcus salivarius, além de estudar os efeitos da interação das preparações e periodontopatógenos em modelo de invertebrado. A atividade antimicrobiana in vitro foi avaliada associando-se as bactérias patogênicas ou comensais a L. reuteri vivo, inativado ou sobrenadante. Após interação, as bactérias foram cultivadas em meio seletivo para contagem de unidades formadoras de colônias (UFC). No estudo em Galleria mellonella, após a infecção com as bactérias patogênicas e as preparações de L. reuteri, foi avaliada a curva de sobrevivência e densidade hemocitária. Os dados foram analisados com o teste estatístico apropriado, ao nível de 5%. Após interação bacteriana in vitro, S. salivarius reduziu o número de UFC de L. reuteri, enquanto que não houve interferência das outras bactérias. O probiótico foi mais eficiente em reduzir o crescimento das bactérias periodontopatogênicas e comensais, exceto para F. nucleatum onde a preparação do sobrenadante foi melhor. In vivo, o sobrenadante foi mais eficiente em aumentar a sobrevivência das lagartas quando infectadas por F. nucleatum. Entretanto, quando infectadas por A. actinomycetemcomitans, nenhuma das preparações aumentou a sobrevivência. Da mesma maneira, nenhuma das preparações aumentaram o número de hemócitos das lagartas após infecção por F. nucleatum e A. actinomycetemcomitans, apesar de todas resultarem em redução na contagem de colônias das bactérias periodontopatogênicas. Dessa forma, concluiu-se que tanto o probiótico quanto os produtos dele derivados apresentaram efeitos antimicrobianos e aumentaram a sobrevivência de G. mellonella quando infectada por F. nucleatum(AU)

Periodontal disease, a chronic multifactorial inflammatory disease, is among the major oral diseases that affects the worldwide population. Among the bacteria associated with periodontitis are Fusobacterium nucleatum and Aggregactibacter actinomycetemcomitans. New therapies have been proposed for periodontal disease as adjunct to conventional treatment, including the use of probiotics. However, their use isn't risk-free and an alternative to that is the inactivation of the microorganisms, maintaining their beneficial properties, which occurs with the paraprobiotics. Thus, the objective of this study is to evaluate the antimicrobial effects of living and heat-killed L. reuteri, and its products on F. nucleatum, A. actinomycetemcomitans and on the commensal bacteria, Streptococcus mitis and Streptococcus salivarius, as well as to study the interaction of the preparations and periodontopathogens in an invertebrate model. In vitro antimicrobial activity was evaluated by associating the pathogenic or commensal bacteria to live, heat killed or L. reuteri supernatant. After interaction, the bacteria were cultured in a selective medium for colony-forming unit (CFU) count. In the study with Galleria mellonella, after infection with pathogenic bacteria and L. reuteri preparations, the survival curve and hemocyte density were evaluated. The data were analyzed with the appropriate statistical test at the 5% level. After bacterial interaction in vitro, S. salivarius reduced the number of CFU of L. reuteri, while there was no interference of the other bacteria. The probiotic was more efficient in reducing the growth of periodontopathogenic and commensal bacteria, except for F. nucleatum. In this case, the supernatant presented better results. In vivo, the supernatant was more efficient in increasing the larvae survival when infected by F. nucleatum. However, when infected by A. actinomycetemcomitans, none of the preparations increased the survival. Likewise, none of the preparations increased the number of hemocytes of the larvae after infection by F. nucleatum and A. actinomycetemcomitans, although all resulted in reduction in the CFU of the periodontopathogenic bacteria. Thus, it was concluded that the probiotic and the products derived therefrom presented antimicrobial effects and increased the survival of G. mellonella when infected by F. nucleatum(AU)