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Bacteriocins are peptides produced by bacteria to inhibit the growth of other prokaryotes. Nisin is a bacteriocin widely used in the food industry and for biomedical applications. However, bacteriocins have some limitations, as they experience mechanisms of resistance, degradation by proteases, and suboptimal intracellular delivery. Combining bacteriocins with nanoscale drug delivery systems (nano-DDS) is an approach that can help overcome these limitations. Among the nano-DDS, solid lipid nanoparticles (SLN) have been described as promising candidates, because of their potential for industrial scale-up and lower toxicity. The objective of this proof-of-concept study was to investigate the use of nisin-loaded SLN (SLN-Nisin) as an antimicrobial and anticancer therapeutic. We show that SLN-Nisin can significantly inhibit the growth of the oral pathogen, Treponema denticola, disrupt oral biofilms, and decrease oral squamous cell carcinoma cell (OSCC) viability compared to free nisin. Further, analysis with scanning electron microscopy (SEM) revealed significant morphological changes in OSCC cells challenged with SLN-Nisin, compared to the empty-nanoparticle or free nisin, indicating that SLN-Nisin likely decreases cell viability by increasing pore formation. This data reveals that nano-DDS are robust tools that can enhance bacteriocin properties.

RATIONALE AND OBJECTIVE: The safety of intensive blood pressure (BP) targets is controversial for persons with chronic kidney disease (CKD). We studied the effects of hypertension treatment on cerebral perfusion and structure in those with and without CKD. STUDY DESIGN: Neuroimaging substudy of a randomized trial. SETTING & PARTICIPANTS: A subset of participants in the Systolic Blood Pressure Intervention Trial who underwent brain MRI studies. Presence of baseline CKD was assessed by estimated glomerular filtration rate (eGFR) and urine albumin to creatinine ratio (UACR). INTERVENTION: Participants were randomly assigned to intensive (systolic BP 30 mg/g (N=151), the effects of intensive versus standard BP treatment on change in global cerebral blood flow, WMLs and total brain volume were 1.91 ml/100g/min (95% CI −3.01, 6.82), 0.003 cm(3) (asinh transformed, 95% CI −0.13, 0.13), and −7.0 cm(3) (95% CI −13.3, −0.3), respectively. The overall treatment effects on cerebral blood flow and total brain volume were not modified by baseline eGFR or UACR; however the effect on WMLs was attenuated in participants with albuminuria (interaction p-value 0.04). LIMITATIONS: Measurement variability due to multi-site design. CONCLUSIONS: Among hypertensive adults with primarily early kidney disease, intensive versus standard blood pressure treatment did not appear to have a detrimental effect on brain perfusion or structure. The findings support the safety of intensive blood pressure treatment targets on brain health in persons with early kidney disease. FUNDING: The Systolic Blood Pressure Intervention Trial was funded by the National Institutes of Health (including the National Heart, Lung, and Blood Institute, the National Institute of Diabetes and Digestive and Kidney Diseases, the National Institute on Aging, and the National Institute of Neurological Disorders and Stroke), and this substudy was funded by the National Institutes of Diabetes and Digestive and Kidney Diseases. TRIAL REGISTRATION: SPRINT was registered at ClinicalTrials.gov with the study number NCT01206062.

Periodontal disease is driven by dysbiosis in the oral microbiome, resulting in over-representation of species that induce the release of pro-inflammatory cytokines, chemokines, and tissue-remodeling matrix metalloproteinases (MMPs) in the periodontium. These chronic tissue-destructive inflammatory responses result in gradual loss of tooth-supporting alveolar bone. The oral spirochete Treponema denticola, is consistently found at significantly elevated levels in periodontal lesions. Host-expressed Toll-Like Receptor 2 (TLR2) senses a variety of bacterial ligands, including acylated lipopolysaccharides and lipoproteins. T. denticola dentilisin, a surface-expressed protease complex comprised of three lipoproteins has been implicated as a virulence factor in periodontal disease, primarily due to its proteolytic activity. While the role of acylated bacterial components in induction of inflammation is well-studied, little attention has been given to the potential role of the acylated nature of dentilisin. The purpose of this study was to test the hypothesis that T. denticola dentilisin activates a TLR2-dependent mechanism, leading to upregulation of tissue-destructive genes in periodontal tissue. RNA-sequencing of periodontal ligament cells challenged with T. denticola bacteria revealed significant upregulation of genes associated with extracellular matrix organization and degradation including potentially tissue-specific inducible MMPs that may play novel roles in modulating host immune responses that have yet to be characterized within the context of oral disease. The Gram-negative oral commensal, Veillonella parvula, failed to upregulate these same MMPs. Dentilisin-induced upregulation of MMPs was mediated via TLR2 and MyD88 activation, since knockdown of expression of either abrogated these effects. Challenge with purified dentilisin upregulated the same MMPs while a dentilisin-deficient T. denticola mutant had no effect. Finally, T. denticola-mediated activation of TLR2/MyD88 lead to the nuclear translocation of the transcription factor Sp1, which was shown to be a critical regulator of all T. denticola-dependent MMP expression. Taken together, these data suggest that T. denticola dentilisin stimulates tissue-destructive cellular processes in a TLR2/MyD88/Sp1-dependent fashion., Author summary Periodontal disease is driven by dysbiosis of the oral microbiome, which interacts with host tissues and thereby induces the release of pro-inflammatory cytokines, chemokines, and tissue-remodeling matrix metalloproteinases (MMPs), leading to destruction of the periodontal tissues. Even after clinical intervention, patients with severe periodontal disease are left with a persistent pro-inflammatory transcriptional profile throughout the periodontium. The oral spirochete, Treponema denticola is consistently found at elevated levels in periodontal lesions and is associated with several pathophysiological effects driving periodontal disease progression. The T. denticola surface-expressed protease complex (dentilisin) has cytopathic effects consistent with periodontal disease pathogenesis. To date, few direct links have been reported between dentilisin and the cellular and tissue processes that drive periodontal tissue destruction at the transcriptional and/or epigenetic levels. Here, we utilize wild type and dentilisin-deficient T. denticola as well as purified dentilisin to characterize dentilisin-dependent activation of intracellular pathways controlling MMP expression and activity. Our results define a role for dentilisin in initiating this signal cascade. Also, our study identified tissue-specific inducible MMPs that may play novel roles in modulating as-yet uncharacterized host responses in periodontal disease. Lastly, T. denticola dentilisin stimulates tissue-destructive cellular processes in a TLR2/MyD88/Sp1-dependent fashion. Taken together, our study provides new insights into the molecular mechanisms underpinning periodontal disease progression which could lead to the development of more efficacious therapeutic treatments.

The periodontal complex consists of the periodontal ligament (PDL), alveolar bone, and cementum, which work together to turn mechanical load into biological responses that are responsible for maintaining a homeostatic environment. However oral microbes, under conditions of dysbiosis, may challenge the actin dynamic properties of the PDL in the context of periodontal disease. To study this process, we examined host-microbial interactions in the context of the periodontium via molecular and functional cell assays and showed that human PDL cell interactions with Treponema denticola induce actin depolymerization through a novel actin reorganization signaling mechanism. This actin reorganization mechanism and loss of cell adhesion is a pathological response characterized by an initial upregulation of RASA4 mRNA expression resulting in an increase in matrix metalloproteinase-2 activity. This mechanism is specific to the T. denticola effector protein, dentilisin, thereby uncovering a novel effect for Treponema denticola-mediated RASA4 transcriptional activation and actin depolymerization in primary human PDL cells.

Background Oral dysbiosis is an imbalance in the oral microbiome and is associated with a variety of oral and systemic diseases, including periodontal disease, caries, and head and neck/oral cancer. Although antibiotics can be used to control this dysbiosis, they can lead to adverse side effects and superinfections. Thus, novel strategies have been proposed to address these shortcomings. One strategy is the use of probiotics as antimicrobial agents, since they are considered safe for humans and the environment. Specifically, the Gram-positive Lactococcus lactis, a species present in the oral and gut microbiota, is able to produce nisin, which has been used worldwide for food preservation. Objective The objective of this study was to test whether a nisin probiotic can promote a healthier oral microbiome in pathogen-spiked oral biofilms. Results We found that L. lactis can prevent oral biofilm formation and disrupt 24-h and 48-h pre-formed biofilms. Finally, we demonstrate that both treatments, a nisin-producing L. lactis probiotic and nisin can decrease the levels of pathogens in the biofilms and return the diversity levels back to control or ‘healthy’ levels. Conclusion A nisin-producing probiotic, can be used to treat ‘disease-altered’ biofilms and promote healthier oral biofilms, which may be useful for improving patient oral health.

Periodontal studies using transcriptomics, proteomics, and metabolomics encompass the collection of mRNA transcripts, proteins, and small-molecule chemicals in the context of periodontal health and disease. The number of studies using these approaches has significantly increased in the last decade and they have provided new insight into the pathogenesis and host-microbe interactions that define periodontal diseases. This review provides an overview of current molecular findings using -omic approaches that underlie periodontal disease, including modulation of the host immune response, tissue homeostasis, and complex metabolic processes of the host and the oral microbiome. Integration of these -omic approaches will broaden our perspective of the molecular mechanisms involved in periodontal disease, advancing and improving the diagnosis and treatment of various stages and forms of periodontal disease.

To report the clinical signs, diagnostic findings, surgical treatment, postoperative complications, and long-term outcome in 2 adult alpacas with large intra-abdominal abscesses treated by marsupialization of the abscess to the ventral body wall.Clinical report.Alpacas (n = 2).Two alpacas each presented with decreased appetite, lethargy, poor body condition, and marked abdominal distension. A complete physical examination, abdominal radiography, and ultrasonography confirmed the presence of large intra-abdominal abscesses. Streptococcus equi ssp. zooepidemicus was cultured from the abscess fluid of alpaca 1, and a Gram-negative bacillus from alpaca 2.Both alpacas had exploratory celiotomy with marsupialization of the abdominal abscess to the ventral body wall. Postoperatively, alpacas were administered systemic antibiotics and non-steroidal anti-inflammatory drugs, and the abscesses were lavaged for several days. Alpaca 2 required a second surgical procedure. The abscesses ultimately resolved in both alpacas, with body wall hernia formation as the only major complication. Both alpacas had good long-term outcomes.Marsupialization to the ventral abdominal wall with concurrent antibiotic treatment should be considered as a treatment option for alpacas with large intra-abdominal abscesses in which complete surgical resection of the abscess is not possible. An abdominal wall hernia can result from this procedure, and clients should be informed of this potential complication before surgery.

A 12-year-old Quarter horse gelding was presented for evaluation of severe right forelimb lameness, 2 draining tracts over the lateral aspect of the right proximal antebrachium, and weight loss. A presumptive diagnosis of blastomycotic osteomyelitis was established based on radiographs and cytology of the exudate. This diagnosis was confirmed at necropsy.

The risk of acquiring certain types of cancers has many causes which include age, environment and genetics. There have been advances in the primary treatment options available, which include surgery, radiation therapy, and chemotherapy. However, the survival prognosis for many cancer patients remains low. Cancer treatments may involve chemotherapy, which often cause harsh side effects. The Plant kingdom may provide alternative therapy that may have less side effects and possibly more effective. Hypericum perforatum possesses hypericin, which has been been shown to have antitumor effects with invitro studies on specific cell lines. In other Hypericum species, hypericin makes up a smaller percentage of the extract. However, these species contain other phytochemical compounds that may also exert an antitumor effect. The objective of the present study was to assess the cytotoxic potential of H. perforatum cv. topas, H. olympicum, and H. calycinum on breast and colorectal adenocarcinoma cell lines. MCF7, SW480, and SW620 cells were treated with varying concentrations dosages of methanolic crude extracts from the plant species. Cytotoxicity was determine by measuring the reduction of Alamar Blue after a 24 hour exposure period of 10,000 cells in 96 well fluorescent plates. The reduction was determine using the Molecular Devices fluorescent spectrophotometer. At the lowest comparable concentrations, H. perforatum cv. topas had a greater reduction in tumor growth than MCF7 and SW40 cells lines. Whereas, H. olympicum demonstrated a greater decrease in SW620 cell growth at the lowest comparable concentration. These results suggest a difference in the phytochemical composition of these plants, which should be evaluated in order to determine what metabolite(s) are having the antitumor effect and their target. Citation Format: Carla Gibbs, Johnette S. Duggans, Erin Malone, Elbert L. Myles. Cytotoxic effects of hypericum extracts on breast and colorectal tumors. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5117. doi:10.1158/1538-7445.AM2014-5117