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Erdogan, O.

Publications and source records attributed to Erdogan, O..

6 recordsLinked to original sources

Hypomineralized Enamel Alters Trigeminal Sensory Afferent Architecture, Transcriptome, and Dental Injury Responses

At barrier tissues such as the skin and gut, sensory neurons interface with environmental stimuli and coordinate with neighboring epithelial and immune cells to detect tissue perturbations. In teeth, however, the sensory dentin-pulp complex is insulated from the oral environment by highly mineralized enamel. Although dentin-pulp responses to severe injury have been studied in models with direct pulp exposure, it remains unclear whether enamel barrier dysfunction alone alters pulpal and neuronal homeostasis. Using a kallikrein-related peptidase 4 knockout (KLK4 KO) mouse model of enamel hypomineralization, we demonstrated that defective enamel induced structural, molecular, and transcriptional responses in the dental pulp and in the trigeminal system innervating teeth, despite the absence of direct pulp exposure to the oral cavity. Hypomineralized molars exhibited increased reactionary dentin formation accompanied by retraction of sensory afferents from the dentin-pulp junction. Consistent with these structural findings, trigeminal ganglia of KLK4 KO mice displayed upregulation of genes associated with cytoskeletal remodeling and stimulus response pathways. Despite increased bacterial burden and biofilm accumulation on the enamel surface, enamel hypomineralization did not induce substantial innate immune responses in the pulp. In addition, following severe dental pulp injury, teeth with hypomineralized enamel exhibited reduced sensory afferent loss and tissue damage. Together, these findings reveal that enamel integrity functions as a critical regulator of dentin-pulp homeostasis and that barrier dysfunction alone can precondition tissue responses to subsequent injury.

neuroscience↗

Vagal TRPV1+ sensory neurons regulate myeloid cell dynamics and protect against influenza virus infection

Influenza viruses are a major global cause of morbidity and mortality. Vagal TRPV1+ nociceptive sensory neurons, which innervate the airways, are known to mediate defenses against harmful agents. However, their function in lung antiviral defenses remains unclear. Our study reveals that both systemic and vagal-specific ablation of TRPV1+ nociceptors reduced survival in mice infected with influenza A virus (IAV), despite no significant changes in viral burden or weight loss. Mice lacking nociceptors showed exacerbated lung pathology and elevated levels of pro-inflammatory cytokines. The increased mortality was not attributable to the loss of the TRPV1 ion channel or neuropeptides CGRP or substance P. Immune profiling through flow cytometry and single-cell RNA sequencing identified significant nociceptor deficiency-mediated changes in the lung immune landscape, including an expansion of neutrophils and monocyte-derived macrophages. Transcriptional analysis revealed impaired interferon signaling in these myeloid cells and an imbalance in distinct neutrophil sub-populations in the absence of nociceptors. Furthermore, anti-GR1-mediated depletion of myeloid cells during IAV infection significantly improved survival, underscoring a role of nociceptors in preventing pathogenic myeloid cell states that contribute to IAV-induced mortality. One Sentence Summary: TRPV1+ neurons facilitate host survival from influenza A virus infection by controlling myeloid cell responses and immunopathology.

immunology↗

Dynamics of Innate Immune Response Due to Bacteria-Induced Pulpitis

IntroductionPulpitis is associated with dental carries and can lead to irreversible pulp damage. As bacteria penetrate deeper into dentin and pulp tissue, a pulpal innate immune response is initiated. However, an understanding of the types of immune cells in the pulp, how this relates to bacterial infiltration, and the dynamics of the immune response during pulpitis is limited. As conserving the vitality of the pulp tissue through conservative therapies becomes an important part of dental practice, there is a greater need to understand the kinetics and composition of the immune response during pulpitis. MethodsDental pulp exposure in molars of mice was used as an animal model of pulpitis. To investigate the kinetics of immune response, pulp tissue was collected from permanent molars at different time points after injury (baseline, day 1, and day 7). Flow cytometry analysis of CD45+ leukoctyes including macrophages, T cells, neutrophils and monocytes was performed. 16S in situ hybridization captured bacterial invasion of the pulp, and immunohistochemistry for F4/80 investigated spatial and morphological changes of macrophages during pulpitis. Data were analyzed using two-way ANOVA with Tukeys multiple comparisons. ResultsBacteria mostly remained close to the injury site, with some expansion towards non-injured pulp horns. We found that F4/80+ macrophages were the main immune cell population in healthy pulp. Upon injury, CD11b+Ly6Ghigh neutrophils and CD11b+Ly6GintLy6Cint monocytes constituted 70-90% of all immune populations up to 7 days after injury. Even though there was a slight increase in T cells at day 7, myeloid cells remained the main drivers of the immune response. ConclusionsAs bacteria proliferate within the pulp chamber, innate immune cells including macrophages, neutrophils and monocytes predominate as the major immune populations, with minimal signs of transitioning to an adaptive immune response.

immunology↗

Neuronal-immune Axis Alters Pain and Sensory Afferent Damage During Dental Pulp Injury

Dental pulp tissue is densely innervated by afferent fibers of the trigeminal ganglion. When bacteria cause dental decay near the pulpal tissue, a strong neuronal and immune response occur, creating pulpitis, which is associated with severe pain and pulp tissue damage. Neuro-immune interactions have the potential to modulate both the pain and pathological outcome of pulpitis. We first investigated the role of the neuropeptide calcitonin-gene related peptide (CGRP), released from peptidergic sensory afferents, in dental pain and immune responses by using calca knock out (calca-/-) and wild type (calca+/+) mice, in a model of pulpitis by creating a mechanical exposure of the dental pulp horn. While CGRP did not contribute to facial mechanical hypersensitivity, at an early time point, it did contribute to spontaneous pain-like behavior. We also found that CGRP contributed to recruitment of neutrophils and monocytes, while not clearly affecting the progression of pulpal pathology histologically. When we depleted neutrophils and monocytes, we found that there was more sensory afferent loss, tissue damage and deeper spread of bacteria into the pulp tissue, while there was a reduction in facial mechanical hypersensitivity compared to control animals at a later time point. Overall, we showed that there is a crosstalk between peptidergic neurons and neutrophils in the pulp, modulating the pain and inflammatory outcomes of the disease.

neuroscience↗

RAS mutation patterns arise from tissue-specific responses to distinct oncogenic signaling

Despite multiple possible oncogenic mutations in the proto-oncogene KRAS, unique subsets of these mutations are detected in different cancer types. As KRAS mutations occur early, if not being initiating, these mutational biases are ostensibly a product of how normal cells respond to the encoded oncoprotein. Oncogenic mutations can impact not only the level of active oncoprotein, but also engagement with effectors and other proteins. To separate these two effects, we generated four novel inducible Kras alleles encoded by the biochemically distinct mutations G12D versus Q61R encoded by native (nat) rare versus common (com) codons to produce either low or high protein levels. Each allele induced a distinct transcriptional response in normal cells. At one end of the spectrum, the KrasnatG12D allele induced transcriptional hallmarks suggestive of an expansion of multipotent cells, while at the other end, the KrascomQ61R allele exhibited all the hallmarks of oncogenic stress and inflammation. Further, this dramatic difference in the transcriptomes of normal cells appears to be a product of signaling differences due to increased protein expression as well as the specific mutation. To determine the impact of these distinct responses on RAS mutational patterning in vivo, all four alleles were globally activated, revealing that hematolymphopoietic lesions were sensitive to the level of active oncoprotein, squamous tumors were sensitive to the G12D mutant, while carcinomas were sensitive to both these features. Thus, we identify how specific KRAS mutations uniquely signal to promote the conversion of normal hematopoietic, epithelial, or squamous cells towards a tumorigenic state.

cancer biology↗

Descriptors of Pain Quality Associate with Pulpal and Periapical Diagnostic Tests in Patients Experiencing Acute Tooth Pain

Introduction Introduction Material And Methods Results Discussion References Dental pain causes a great deal of suffering, stress, and interference in the lives of patients, and relief from pain is a common reason for seeking dental care (Heaivilin et al. 2011). However, how we typically measure pain in dentistry does little to capture the complex experience of pain. Scales such as the visual analog scale (VAS) or numeric rating scale (NRS) are the most commonly used, and allow for the quantification of pain intensity. Used alone, as is most often then case, these scales are quite limited, given the multidimensional nature of pain, with sensory, affective, and temporal dimensions mediated by complex and varied biological mechanisms (Dworkin et al. 2005; von Hehn et al. 2012). Pain ...

neuroscience↗