Modulation of tooth regeneration through opposing responses to Wnt and BMP signals in teleosts.

Most vertebrate species undergo tooth replacement throughout adult life. This process is marked by the shedding of existing teeth and the regeneration of tooth organs. However, little is known about the genetic circuitry regulating tooth replacement. Here, we tested whether fish orthologs of genes known to regulate mammalian hair regeneration have effects on tooth replacement. Using two fish species that demonstrate distinct modes of tooth regeneration, threespine stickleback (Gasterosteus aculeatus) and zebrafish (Danio rerio), we found that transgenic overexpression of four different genes changed tooth replacement rates in the direction predicted by a hair regeneration model: Wnt10a and Grem2a increased tooth replacement rate, whereas Bmp6 and Dkk2 strongly inhibited tooth formation. Thus, similar to known roles in hair regeneration, Wnt and BMP signals promote and inhibit regeneration, respectively. Regulation of total tooth number was separable from regulation of replacement rates. RNA sequencing of stickleback dental tissue showed that Bmp6 overexpression resulted in an upregulation of Wnt inhibitors. Together, these data support a model in which different epithelial organs, such as teeth and hair, share genetic circuitry driving organ regeneration.

Evolution of Spatial and Temporal cis-Regulatory Divergence in Sticklebacks.

Cis-regulatory changes are thought to play a major role in adaptation. Threespine sticklebacks have repeatedly colonized freshwater habitats in the Northern Hemisphere, where they have evolved a suite of phenotypes that distinguish them from marine populations, including changes in physiology, behavior, and morphology. To understand the role of gene regulatory evolution in adaptive divergence, here we investigate cis-regulatory changes in gene expression between marine and freshwater ecotypes through allele-specific expression (ASE) in F1 hybrids. Surveying seven ecologically relevant tissues, including three sampled across two developmental stages, we identified cis-regulatory divergence affecting a third of genes, nearly half of which were tissue-specific. Next, we compared allele-specific expression in dental tissues at two timepoints to characterize cis-regulatory changes during development between marine and freshwater fish. Applying a genome-wide test for selection on cis-regulatory changes, we find evidence for lineage-specific selection on several processes between ecotypes, including the Wnt signaling pathway in dental tissues. Finally, we show that genes with ASE, particularly those that are tissue-specific, are strongly enriched in genomic regions of repeated marine-freshwater divergence, supporting an important role for these cis-regulatory differences in parallel adaptive evolution of sticklebacks to freshwater habitats. Altogether, our results provide insight into the cis-regulatory landscape of divergence between stickleback ecotypes across tissues and during development, and support a fundamental role for tissue-specific cis-regulatory changes in rapid adaptation to new environments.

Alterations of whole body glucose metabolism in a feline SARS-CoV-2 infection model.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been especially devastating to patients with comorbidities, including metabolic and cardiovascular diseases. Elevated blood glucose during SARS-CoV-2 infection increased mortality of patients with COVID-19, although the mechanisms are not well understood. It has been previously demonstrated that glucose transport and utilization is a crucial pathway for other highly infectious RNA viruses. Thus, we hypothesized that SARS-CoV-2 infection could lead to alterations in cellular and whole body glucose metabolism. Specific pathogen-free domestic cats were intratracheally inoculated with USA-WA1/2020 (wild-type) SARS-CoV-2 or vehicle-inoculated, then euthanized at 4- and 8-days postinoculation (dpi). Blood glucose and cortisol concentrations were elevated at 4 and 8 dpi. Blood ketones, insulin, and angiotensin II concentrations remained unchanged throughout the experimental timeline. SARS-CoV-2 RNA was detected in the lung and heart, without changes in angiotensin-converting enzyme 2 (ACE2) RNA expression. In the lung, SARS-CoV-2 infection increased glucose transporter 1 (GLUT1) protein levels at 4 and 8 dpi, whereas GLUT4 level was only upregulated at 8 dpi. In the heart, GLUT-1 and -4 protein levels remained unchanged. Furthermore, GLUT1 level was upregulated in the skeletal muscle at 8 dpi, and AMPK was activated in the hearts of infected cats. SARS-CoV-2 infection increased blood glucose concentration and pulmonary GLUT protein levels. These findings suggest that SARS-CoV-2 infection induces metabolic reprogramming primarily in the lung to support viral replication. Furthermore, this translational feline model mimicked human COVID-19 and could be used to explore novel therapeutic targets to treat metabolic disease during SARS-CoV-2 infection.NEW & NOTEWORTHY Our study on a feline model of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, mirroring human COVID-19, revealed alterations in whole body and cellular glucose metabolism. Infected cats developed mild hyperglycemia, increased protein levels of glucose transporters in the lung, and AMPK activation in the heart. These findings suggest that SARS-CoV-2 infection induces metabolic reprogramming in the cardiorespiratory system to support viral replication. Understanding these mechanisms could lead to novel antiviral therapeutic strategies.

Realizing the clinical utility of saliva for monitoring oral diseases.

In the era of personalized/precision health care, additional effort is being expended to understand the biology and molecular mechanisms of disease processes. How these mechanisms are affected by individual genetics, environmental exposures, and behavioral choices will encompass an expanding role in the future of optimally preventing and treating diseases. Considering saliva as an important biological fluid for analysis to inform oral disease detection/description continues to expand. This review provides an overview of saliva as a diagnostic fluid and the features of various biomarkers that have been reported. We emphasize the use of salivary biomarkers in periodontitis and transport the reader through extant literature, gaps in knowledge, and a structured approach toward validating and determine the utility of biomarkers in periodontitis. A summation of the findings support the likelihood that a panel of biomarkers including both host molecules and specific microorganisms will be required to most effectively identify risk for early transition to disease, ongoing disease activity, progression, and likelihood of response to standard periodontal therapy. The goals would be to develop predictive algorithms that serve as adjunctive diagnostic tools which provide the clinician and patient important information for making informed clinical decisions.

Influenza virus infection exacerbates gene expression related to neurocognitive dysfunction in brains of old mice.

BACKGROUND: Age > 65 years is a key risk factor for poor outcomes after human influenza infection. Specifically, in addition to respiratory disease, non-neurotropic influenza A virus (IAV) causes neuro-cognitive complications, e.g. new onset depression and increases the risk of dementia after hospitalization. This study aimed to identify potential mechanisms of these effects by determining differences between young and old mice in brain gene expression in a mouse model of non-neurotropic IAV infection. METHODS: Young (12 weeks) and old (70 weeks) C57Bl/6J mice were inoculated intranasally with 200 PFU H1N1 A/PR/34/8 (PR8) or sterile PBS (mock). Gene expression in lung and brain was measured by qRT-PCR and normalized to ß-actin. Findings were confirmed using the nCounter Mouse Neuroinflammation Array (NanoString) and analyzed with nSolver 4.0 and Ingenuity Pathway Analysis (IPA, Qiagen). RESULTS: IAV PR8 did not invade the central nervous system. Young and old mice differed significantly in brain gene expression at baseline and during non-neurotropic IAV infection. Expression of brain Ifnl, Irf7, and Tnf mRNAs was upregulated over baseline control at 3 days post-infection (p.i.) only in young mice, but old mice expressed more Ifnl than young mice 7 days p.i. Gene arrays showed down-regulation of the Epigenetic Regulation, Insulin Signaling, and Neurons and Neurotransmission pathways in old mice 3 days p.i. while young mice demonstrated no change or induction of these pathways at the same time point. IPA revealed marked baseline differences between old and young mice. Gene expression related to Cognitive Impairment, Memory Deficits and Learning worsened in old mice relative to young mice during IAV infection. Aged mice demonstrate more severe changes in gene expression related to memory loss and cognitive dysfunction by IPA. CONCLUSIONS: These data suggest the genes and pathways related to learning and cognitive performance that were worse at baseline in old mice were further worsened by IAV infection, similar to old patients. Early events in the brain triggered by IAV infection portend downstream neurocognitive pathology in old adults.

A review of animal models for burning mouth syndrome: Mechanistic insights and knowledge gaps.

OBJECTIVES: The underlying mechanisms of burning mouth syndrome (BMS) remain unclear leading to challenges and unsatisfactory management. Current treatments focus primarily on symptom relief, with few consistently achieving a 50% reduction in pain. This review aims to explore animal models of BMS to gain a better understanding of the underlying mechanisms and to discuss potential and existing knowledge gaps. METHODS: A comprehensive review of PubMed® , Google Scholar, and Scopus was performed to assess advances and significant gaps of existing rodent models that mimic BMS-related symptoms. RESULTS: Rodent models of BMS involve reproduction of dry-tongue, chorda tympani transection, or overexpression of artemin protein. Existing preclinical models tend to highlight one specific etiopathogenesis and often overlook sex- and hormone-specific factors. CONCLUSION: Combining aspects from various BMS models could prove beneficial in developing comprehensive experimental designs and outcomes encompassing the multifaceted nature of BMS.

Alternatives to dental opioid prescribing after tooth extraction (ADOPT): protocol for a stepped wedge cluster randomized trial.

BACKGROUND: Dentists and oral surgeons are leading prescribers of opioids to adolescents and young adults (AYA), who are at high risk for developing problematic opioid use after an initial exposure. Most opioids are prescribed after tooth extraction, but non-opioid analgesics provide similar analgesia and are recommended by multiple professional organizations. METHODS: This multi-site stepped wedge cluster-randomized trial will assess whether a multicomponent behavioral intervention can influence opioid prescribing behavior among dentists and oral surgeons compared to usual practice. Across up to 12 clinical practices (clusters), up to 33 dentists/oral surgeons (provider participants) who perform tooth extractions for individuals 12-25 years old will be enrolled. After enrollment, all provider participants will receive the intervention at a time based on the sequence to which their cluster is randomized. The intervention consists of prescriber education via academic detailing plus provision of standardized patient post-extraction instructions and blister packs of acetaminophen and ibuprofen. Provider participants will dispense the blister packs and distribute the patient instructions at their discretion to AYA undergoing tooth extraction, with or without additional analgesics. The primary outcome is a binary, patient-level indicator of electronic post-extraction opioid prescription. Data for the primary outcome will be collected from the provider participant's electronic health records quarterly throughout the study. Provider participants will complete a survey before and approximately 3 months after transitioning into the intervention condition to assess implementation outcomes. AYA patients undergoing tooth extraction will be offered a survey to assess pain control and satisfaction with pain management in the week after their extraction. Primary analyses will use generalized estimating equations to compare the binary patient-level indicator of being prescribed a post-extraction opioid in the intervention condition compared to usual practice. Secondary analyses will assess provider participants' perceptions of feasibility and appropriateness of the intervention, and patient-reported pain control and satisfaction with pain management. Analyses will adjust for patient-level factors (e.g., sex, number of teeth extracted, etc.). DISCUSSION: This real-world study will address an important need, providing information on the effectiveness of a multicomponent intervention at modifying dental prescribing behavior and reducing opioid prescriptions to AYA. CLINICALTRIALS: GOV: NCT06275191.

Statistical modeling to quantify the uncertainty of FoldX-predicted protein folding and binding stability.

BACKGROUND: Computational methods of predicting protein stability changes upon missense mutations are invaluable tools in high-throughput studies involving a large number of protein variants. However, they are limited by a wide variation in accuracy and difficulty of assessing prediction uncertainty. Using a popular computational tool, FoldX, we develop a statistical framework that quantifies the uncertainty of predicted changes in protein stability. RESULTS: We show that multiple linear regression models can be used to quantify the uncertainty associated with FoldX prediction for individual mutations. Comparing the performance among models with varying degrees of complexity, we find that the model precision improves significantly when we utilize molecular dynamics simulation as part of the FoldX workflow. Based on the model that incorporates information from molecular dynamics, biochemical properties, as well as FoldX energy terms, we can generally expect upper bounds on the uncertainty of folding stability predictions of ± 2.9 kcal/mol and ± 3.5 kcal/mol for binding stability predictions. The uncertainty for individual mutations varies; our model estimates it using FoldX energy terms, biochemical properties of the mutated residue, as well as the variability among snapshots from molecular dynamics simulation. CONCLUSIONS: Using a linear regression framework, we construct models to predict the uncertainty associated with FoldX prediction of stability changes upon mutation. This technique is straightforward and can be extended to other computational methods as well.

Site pleiotropy of a stickleback Bmp6 enhancer.

Development and regeneration are orchestrated by gene regulatory networks that operate in part through transcriptional enhancers. Although many enhancers are pleiotropic and are active in multiple tissues, little is known about whether enhancer pleiotropy is due to 1) site pleiotropy, in which individual transcription factor binding sites (TFBS) are required for activity in multiple tissues, or 2) multiple distinct sites that regulate expression in different tissues. Here, we investigated the pleiotropy of an intronic enhancer of the stickleback Bone morphogenetic protein 6 (Bmp6) gene. This enhancer was previously shown to regulate evolved changes in tooth number and tooth regeneration, and is highly pleiotropic, with robust activity in both fins and teeth throughout embryonic, larval, and adult life, and in the heart and kidney in adult fish. We tested the hypothesis that the pleiotropy of this enhancer is due to site pleiotropy of an evolutionarily conserved predicted Foxc1 TFBS. Transgenic analysis and site-directed mutagenesis experiments both deleting and scrambling this predicted Foxc1 TFBS revealed that the binding site is required for enhancer activity in both teeth and fins throughout embryonic, larval, and adult development, and in the heart and kidney in adult fish. Collectively these data support a model where the pleiotropy of this Bmp6 enhancer is due to site pleiotropy and this putative binding site is required for enhancer activity in multiple anatomical sites from the embryo to the adult.

Jaw size variation is associated with a novel craniofacial function for galanin receptor 2 in an adaptive radiation of pupfishes.

Understanding the genetic basis of novel adaptations in new species is a fundamental question in biology. Here we demonstrate a new role for galr2 in vertebrate craniofacial development using an adaptive radiation of trophic specialist pupfishes endemic to San Salvador Island, Bahamas. We confirmed the loss of a putative Sry transcription factor binding site upstream of galr2 in scale-eating pupfish and found significant spatial differences in galr2 expression among pupfish species in Meckel's cartilage using in situ hybridization chain reaction (HCR). We then experimentally demonstrated a novel role for Galr2 in craniofacial development by exposing embryos to Garl2-inhibiting drugs. Galr2-inhibition reduced Meckel's cartilage length and increased chondrocyte density in both trophic specialists but not in the generalist genetic background. We propose a mechanism for jaw elongation in scale-eaters based on the reduced expression of galr2 due to the loss of a putative Sry binding site. Fewer Galr2 receptors in the scale-eater Meckel's cartilage may result in their enlarged jaw lengths as adults by limiting opportunities for a circulating Galr2 agonist to bind to these receptors during development. Our findings illustrate the growing utility of linking candidate adaptive SNPs in non-model systems with highly divergent phenotypes to novel vertebrate gene functions.

Biomarker panel discriminates diabetics with and without periodontitis pre- and post-therapy.

BACKGROUND AND OBJECTIVE: Biological regulators of periodontal inflammation, collagen degradation, and insulin resistance have not been determined in association with severity of periodontitis and response to periodontal treatment in diabetics. Our objective was to determine whether type 2 diabetes (T2DM) patients with periodontal disease present a distinct salivary biomarker profile compared with T2DM patients without periodontal disease and healthy subjects (without diabetes and periodontitis) pre- and post-nonsurgical therapy. METHODS: Clinical parameters of periodontal health and whole unstimulated saliva were collected from 92 participants (31 Not Periodontitis, NP; 32 T2DM without periodontitis, DWoP; and 29 with T2DM with periodontitis, DWP) at baseline. The T2DM groups received scaling and root planning (SRP) and provided saliva at 6-week follow-up. Salivary concentrations of interleukin (IL)-1ß, IL-6, matrix metalloproteinase-8 (MMP-8), and resistin were measured by immunoassay. RESULTS: The DWP group had significantly more disease and higher salivary concentrations at baseline for IL-1ß, MMP-8, and resistin (p's < .01) compared with DWoP and NP. SRP resulted in significant improvement in periodontal parameters for the T2DM groups; however, more disease persisted (p < .001), and IL-1ß, MMP-8, and resistin concentrations remained significantly higher in the DWP than the DWoP group (p < .01) at 6 weeks post-treatment. Principal component analysis demonstrated the DWoP group appeared more biologically similar to the NP group than the DWP group. Concentrations of these salivary biomarkers increased with increasing periodontal disease severity (p < .05) in this study population. CONCLUSION: Salivary concentrations of IL-1ß, MMP-8, and resistin appear to serve as biomarkers of periodontal status pre- and post-treatment, irrespective of diabetes status.

WWOM VII: Effectiveness of systemic pharmacotherapeutic interventions in the management of BMS: A systematic review and meta-analysis.

OBJECTIVES: To determine the effectiveness of systemic pharmacotherapeutic interventions compared to placebo in burning mouth syndrome (BMS) randomized controlled trials (RCTs) based on the core outcome domains recommended by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT). METHODS: A systematic literature review of RCTs, concerning systemic pharmacotherapeutic interventions for BMS, published from January 1994 through October 2019, and meta-analysis was performed. RESULTS: Fourteen RCTs (n = 734 participants) were included. Of those, nine were eligible for the quantitative assessment due to the availability/homogeneity of data for at least one of the IMMPACT domains. Pain intensity was the only domain reported in all RCTs. Weighted mean changes in pain intensity, based on visual analogue scale (ΔVAS), were reported in three RCTs at 6 ± 2 weeks and only one RCT at 10+ weeks follow-ups. Quantitative assessment, based on ΔVAS, yielded very low evidence for the effectiveness of alpha-lipoic acid and clonazepam, low evidence for effectiveness of trazodone and melatonin, and moderate evidence for herbal compounds. CONCLUSIONS: Based on the RCTs studied, variable levels of evidence exist that suggest that select pharmacological interventions are associated with improved symptoms. However, the underreporting of IMMPACT domains in BMS RCTs restricts the multidimensional assessment of systemic interventions outcomes. Standardized outcome measures need to be applied to future RCTs to improve understanding of intervention outcomes.

WWOM VII: Effectiveness of topical interventions in the management of burning mouth syndrome: A systematic review.

OBJECTIVES: To assess the effectiveness of topical interventions in the management of burning mouth syndrome (BMS), based on the core outcome domains recommended by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT). METHODS: A systematic literature review of RCTs on topical interventions for the management of BMS, published in PubMed, Web of Science, PsycInfo, Cochrane Database/Central, and Google Scholar through May 2021 was performed. RESULTS: Eight RCTs (n = 358 study participants) were included in this study. Due to underreporting of IMMPACT domains, publication bias, high degree of heterogeneity between studies, meta-analysis was not undertaken. Based on changes in visual analogue pain scores (ΔVAS), the most reported outcome, the effectiveness of the topical interventions was demonstrated; however, it is low level of evidence. CONCLUSIONS: High levels of variability (interventions, outcomes, outcome measurement tools, and intervention effects evaluated), heterogeneity, publication bias, and underreporting of IMMPACT domains were observed across the RCTs. This systematic review highlights the need for application of standardized outcome measures to future RCTs. At the present time, there is lack of moderate-strong evidence on short- and long-term outcomes to support or refute the use of any particular topical intervention in managing BMS. Future RCTs with standardized outcome measures are needed.

Client perspectives on psychotherapy failure.

This study qualitatively examined client's definition and experiences of failed psychotherapy.Thirteen clients were interviewed by phone regarding their experience of failed psychotherapy. Data were analyzed using consensual qualitative research (CQR).Participants defined failed psychotherapy as negatively affecting clients, involving problems in the psychotherapy relationship, and not meeting clients' goals. When describing specific experiences of failed psychotherapy, participants gradually recognized the failure themselves, but the recognition was sometimes facilitated by others. Pre-termination, the failed psychotherapy yielded negative effects (worsened symptoms/functioning, deteriorating relationship, not addressing clients' concerns). Participants perceived therapists' contributions as involving action (insensitive/inappropriate responses to participants' concerns about psychotherapy) and inaction (not managing psychotherapy effectively). They perceived their own contributions as their difficulty voicing their concerns or asserting themselves. Post-termination effects were negative cognitively/affectively (heightened distress), behaviorally (disinterest in seeking mental health services), and interpersonally (relationship difficulties in later psychotherapy); the failed psychotherapy also helped participants pursue their needs in psychotherapy.Failed psychotherapy consisted of problems in the relationship and the treatment not meeting client's goals. Such psychotherapy worsened clients' functioning, further damaged an already tenuous psychotherapy relationship, and both therapists and clients contributed to the failure. After termination, failed psychotherapy yielded cognitive/affective, behavioral, and interpersonal effects.

Searching for a mechanistic description of pairwise epistasis in protein systems.

When two or more amino acid mutations occur in protein systems, they can interact in a nonadditive fashion termed epistasis. One way to quantify epistasis between mutation pairs in protein systems is by using free energy differences: ϵ = ΔΔG1,2  - (ΔΔG1  + ΔΔG2 ) where ΔΔG refers to the change in the Gibbs free energy, subscripts 1 and 2 refer to single mutations in arbitrary order and 1,2 refers to the double mutant. In this study, we explore possible biophysical mechanisms that drive pairwise epistasis in both protein-protein binding affinity and protein folding stability. Using the largest available datasets containing experimental protein structures and free energy data, we derived statistical models for both binding and folding epistasis (ϵ) with similar explanatory power (R2 ) of .299 and .258, respectively. These models contain terms and interactions that are consistent with intuition. For example, increasing the Cartesian separation between mutation sites leads to a decrease in observed epistasis for both folding and binding. Our results provide insight into factors that contribute to pairwise epistasis in protein systems and their importance in explaining epistasis. However, the low explanatory power indicates that more study is needed to fully understand this phenomenon.

Impact of Masks on Speech Recognition in Adult Patients with and without Hearing Loss.

INTRODUCTION: The coronavirus 2019 pandemic has altered how modern healthcare is delivered to patients. Concerns have been raised that masks may hinder effective communication, particularly in patients with hearing loss. The purpose of this study is to determine the effect of masks on speech recognition in adult patients with and without self-reported hearing loss in a clinical setting. METHODS: Adult patients presenting to an otolaryngology clinic were recruited. A digital recording of 36 spondaic words was presented to each participant in a standard clinical exam room. Each word was recorded in 1 of 3 conditions: no mask, surgical mask, or N95 mask. Participants were instructed to repeat back the word. The word recognition score was determined by the percent correctly repeated. RESULTS: A total of 45 participants were included in this study. Overall, the mean word recognition score was 87% without a mask, 78% with a surgical mask, and 61% with an N95 mask. Among the 23 subjects (51.1%) with self-reported hearing loss, the average word recognition score was 46% with an N95 mask compared to 79% in patients who reported normal hearing (p < 0.001). CONCLUSION: Our results suggest that masks significantly decrease word recognition, and this effect is exacerbated with N95 masks, particularly in patients with hearing loss. As masks are essential to allow for safe patient-physician interactions, it is imperative that clinicians are aware they may create a barrier to effective communication.

The potent and selective RIPK2 inhibitor BI 706039 improves intestinal inflammation in the TRUC mouse model of inflammatory bowel disease.

Mouse and human data implicate the NOD1 and NOD2 sensors of the intestinal microbiome and the associated signal transduction via the receptor interacting protein kinase 2 (RIPK2) as a potential key signaling node for the development of inflammatory bowel disease (IBD) and an attractive target for pharmacological intervention. The TRUC mouse model of IBD was strongly indicated for evaluating RIPK2 antagonism for its effect on intestinal inflammation based on previous knockout studies with NOD1, NOD2, and RIPK2. We identified and profiled the BI 706039 molecule as a potent and specific functional inhibitor of both human and mouse RIPK2 and with favorable pharmacokinetic properties. We dosed BI 706039 in the spontaneous TRUC mouse model from age 28 to 56 days. Oral, daily administration of BI 706039 caused dose-responsive and significant improvement in colonic histopathological inflammation, colon weight, and terminal levels of protein-normalized fecal lipocalin (all P values <0.001). These observations correlated with dose responsively increasing systemic levels of the BI 706039 compound, splenic molecular target engagement of RIPK2, and modulation of inflammatory genes in the colon. This demonstrates that a relatively low oral dose of a potent and selective RIPK2 inhibitor can modulate signaling in the intestinal immune system and significantly improve disease associated intestinal inflammation.NEW & NOTEWORTHY The RIPK2 kinase at the apex of microbiome immunosensing is an attractive target for pharmacological intervention. A low oral dose of a RIPK2 inhibitor leads to significantly improved intestinal inflammation in the murine TRUC model of colitis. A selective and potent inhibitor of the RIPK2 kinase may represent a new class of therapeutics that target microbiome-driven signaling for the treatment of IBD.

HIV induces synaptic hyperexcitation via cGMP-dependent protein kinase II activation in the FIV infection model.

Over half of individuals infected with human immunodeficiency virus (HIV) suffer from HIV-associated neurocognitive disorders (HANDs), yet the molecular mechanisms leading to neuronal dysfunction are poorly understood. Feline immunodeficiency virus (FIV) naturally infects cats and shares its structure, cell tropism, and pathology with HIV, including wide-ranging neurological deficits. We employ FIV as a model to elucidate the molecular pathways underlying HIV-induced neuronal dysfunction, in particular, synaptic alteration. Among HIV-induced neuron-damaging products, HIV envelope glycoprotein gp120 triggers elevation of intracellular Ca2+ activity in neurons, stimulating various pathways to damage synaptic functions. We quantify neuronal Ca2+ activity using intracellular Ca2+ imaging in cultured hippocampal neurons and confirm that FIV envelope glycoprotein gp95 also elevates neuronal Ca2+ activity. In addition, we reveal that gp95 interacts with the chemokine receptor, CXCR4, and facilitates the release of intracellular Ca2+ by the activation of the endoplasmic reticulum (ER)-associated Ca2+ channels, inositol triphosphate receptors (IP3Rs), and synaptic NMDA receptors (NMDARs), similar to HIV gp120. This suggests that HIV gp120 and FIV gp95 share a core pathological process in neurons. Significantly, gp95's stimulation of NMDARs activates cGMP-dependent protein kinase II (cGKII) through the activation of the neuronal nitric oxide synthase (nNOS)-cGMP pathway, which increases Ca2+ release from the ER and promotes surface expression of AMPA receptors, leading to an increase in synaptic activity. Moreover, we culture feline hippocampal neurons and confirm that gp95-induced neuronal Ca2+ overactivation is mediated by CXCR4 and cGKII. Finally, cGKII activation is also required for HIV gp120-induced Ca2+ hyperactivation. These results thus provide a novel neurobiological mechanism of cGKII-mediated synaptic hyperexcitation in HAND.

Salivary biomarkers for discriminating periodontitis in the presence of diabetes.

AIM: Salivary biomarkers can help in assessment of periodontitis; however, concentrations may be altered in the presence of diabetes. Hence, the ability of salivary biomarkers to discriminate periodontally healthy type II diabetics (T2DM) from T2DM who have periodontitis was examined. METHODS: Ninety-two participants (29 with T2DM with chronic periodontitis, DWP; 32 T2DM without chronic periodontitis, DWoP; and 31 Not Periodontitis, NP) provided saliva and clinical parameters of periodontal health were recorded. Salivary concentrations of interleukin (IL)-1ß, IL-6, matrix metalloproteinase-8 (MMP-8), macrophage inflammatory protein-1α (MIP-1α), adiponectin and resistin were measured by immunoassay. RESULTS: Salivary analyte concentrations for IL-1ß, MMP-8 and resistin correlated with clinical parameters of periodontitis, with MMP-8 demonstrating the strongest positive correlation with PD ≥5 mm (p < 0.0001). Periodontal health was reflected in salivary analyte concentrations by group, with concentrations of IL-1ß and MMP-8 showing significant associations with periodontitis (p ≤ 0.04) that increased in concentration from health to DWoP to DWP. Odds ratio (OR) analyses showed that MMP-8 discriminated periodontitis from NP (OR of 8.12; 95% CI: 1.01-65.33; p = 0.03) and in the presence of T2DM (DWP vs DWoP, OR = 5.09; 95% CI: 1.24-20.92; p = 0.03). CONCLUSION: Salivary MMP-8 and IL-1ß discriminate periodontitis in T2DM.

Convergent evolution of gene expression in two high-toothed stickleback populations.

Changes in developmental gene regulatory networks enable evolved changes in morphology. These changes can be in cis regulatory elements that act in an allele-specific manner, or changes to the overall trans regulatory environment that interacts with cis regulatory sequences. Here we address several questions about the evolution of gene expression accompanying a convergently evolved constructive morphological trait, increases in tooth number in two independently derived freshwater populations of threespine stickleback fish (Gasterosteus aculeatus). Are convergently evolved cis and/or trans changes in gene expression associated with convergently evolved morphological evolution? Do cis or trans regulatory changes contribute more to gene expression changes accompanying an evolved morphological gain trait? Transcriptome data from dental tissue of ancestral low-toothed and two independently derived high-toothed stickleback populations revealed significantly shared gene expression changes that have convergently evolved in the two high-toothed populations. Comparing cis and trans regulatory changes using phased gene expression data from F1 hybrids, we found that trans regulatory changes were predominant and more likely to be shared among both high-toothed populations. In contrast, while cis regulatory changes have evolved in both high-toothed populations, overall these changes were distinct and not shared among high-toothed populations. Together these data suggest that a convergently evolved trait can occur through genetically distinct regulatory changes that converge on similar trans regulatory environments.