Impact of smoking habit on the subgingival proteome in patients with periodontitis.

BACKGROUND: Few investigations evaluated smoking's impact on the periodontal proteome. Therefore, this study aimed to analyse the influence of tobacco on the overall periodontal proteome and the differential expression of gingival crevicular fluid (GCF) proteins using sequential window acquisition of all theoretical mass spectra (SWATH-MS). METHODS: GCF samples were collected from 40 periodontitis subjects (stages III-IV). These were separated based on smoking status into smokers (17), ex-smokers (10), and non-smokers (13). Samples were analysed using SWATH-MS, and proteins were identified using the UniProt human-specific database. Data are available via ProteomeXchange with the identifier PXD043474. Principal component analysis (PCA) was employed to examine the spectral mass distribution of the proteome. Protein expression was different for a p-value <0.05 and a log2 fold change ≥0.3 (upregulated) or ≤-0.3 (downregulated). RESULTS: The distribution of overall proteome did not differ between non-smokers, smokers, and ex-smokers. Considering protein expression, 23 were differentially expressed in smokers vs. non-smokers (16 upregulated and 7 downregulated), 17 in ex-smokers vs. non-smokers (2 upregulated and 15 downregulated), and only 8 in smokers vs. ex-smokers (7 upregulated and 1 downregulated). Smoking increased the expression of proteins related to epithelial hyperkeratinization (keratins type II cytoskeletal 4, type I cytoskeletal 13 and type I cytoskeletal 19, cornulin, and fatty acid-binding protein 5). However, multiple immunoglobulins were underexpressed when comparing smokers and ex-smokers to non-smokers. CONCLUSION: Although smoking does not significantly modify the overall GCF proteome associated with periodontitis, it alters the expression of several proteins compared to never-smokers and ex-smokers. PLAIN LANGUAGE SUMMARY: Smoking is a critical risk factor for the development and progression of periodontitis. However, evidence of the effect of smoking on the subgingival proteome is scarce. Therefore, this study aimed to determine the impact of smoking on the overall proteome and differential expression of gingival crevicular fluid (GCF) proteins using the sequential window acquisition of all theoretical mass spectra (SWATH-MS) proteomic technique. For this purpose, GCF samples were collected from 40 subjects with periodontitis, of which 17 were smokers, 10 were ex-smokers, and 13 were non-smokers. These samples were analysed by SWATH-MS, and proteins were identified using the UniProt human-specific database. Analysis of the overall proteome showed that its distribution was not significantly different between smokers, ex-smokers, and non-smokers. However, several proteins were found to be differentially expressed according to the smoking status. Smoking can increase the expression of several keratins and proteins related to hyperkeratinization of the epithelium. However, in ex-smokers, these proteins return to similar levels to those of non-smokers. Moreover, smoking may induce a lower expression of proteins related to adaptive immunity, such as immunoglobulins. This immunosuppressive effect may persist in ex-smokers.

Update on the Role of Cytokines as Oral Biomarkers in the Diagnosis of Periodontitis.

Periodontitis is one of the world's most common chronic human diseases and has a significant impact on oral health. Recent evidence has revealed a link between periodontitis and certain severe systemic conditions. Moreover, periodontal patients remain so for life, even following successful therapy, requiring ongoing supportive care to prevent the disease's recurrence. The first challenge in treating the condition is ensuring a timely and accurate diagnosis since the loss of periodontal bone and soft tissue is progressive and largely irreversible. Although current clinical and radiographic parameters are the best available for identifying and monitoring the disease, the scientific community has a particular interest in finding quantifiable biomarkers in oral fluids that can improve early detection rates of periodontitis and evaluations of its severity. It is widely accepted that periodontitis is associated with polymicrobial dysbiosis and a chronic inflammatory immune response in the host. This response causes the generation of mediators like cytokines. Higher concentrations of cytokines are involved in inflammation and disease progression, acting as a network of biological redundancy. Most of the cytokines investigated concerning the periodontitis pathogenesis are proinflammatory. Of all of them, interleukin (IL) 1beta has been studied the most, followed by tumor necrosis factor (TNF) alpha and IL6. In contrast, only a few papers have evaluated antiinflammatory cytokines, with the most researched being IL4 and IL10. Several systemic reviews have concluded that the specific cytokines present in patients with periodontitis have a distinctive profile, which may indicate their possible discriminatory potential. In this chapter, the focus is on analyzing studies that investigate the accuracy of diagnoses of periodontitis based on the cytokines present in gingival crevicular fluid and saliva. The findings of our research group are also described.

Epigenetic Effects of Healthy Foods and Lifestyle Habits from the Southern European Atlantic Diet Pattern: A Narrative Review.

Recent scientific evidence has shown the importance of diet and lifestyle habits for the proper functioning of the human body. A balanced and healthy diet, physical activity, and psychological well-being have a direct beneficial effect on health and can have a crucial role in the development and prognosis of certain diseases. The Southern European Atlantic diet, also named the Atlantic diet, is a unique dietary pattern that occurs in regions that present higher life expectancy, suggesting that this specific dietary pattern is associated with positive health effects. In fact, it is enriched with nutrients of high biological value, which, together with its cooking methods, physical activity promotion, reduction in carbon footprint, and promoting of family meals, promote these positive effects on health. The latest scientific advances in the field of nutri-epigenetics have revealed that epigenetic markers associated with food or nutrients and environmental factors modulate gene expression and, therefore, are involved with both health and disease. Thus, in this review, we evaluated the main aspects that define the Southern European Atlantic diet and the potential epigenetic changes associated with them based on recent studies regarding the main components of these dietary patterns. In conclusion, based on the information existing in the literature, we postulate that the Southern European Atlantic diet could promote healthy aging by means of epigenetic mechanisms. This review highlights the necessity of performing longitudinal studies to demonstrate this proposal.

His452Tyr polymorphism in the human 5-HT2A receptor affects clozapine-induced signaling networks revealed by quantitative phosphoproteomics.

Antipsychotic drugs remain the current standard for schizophrenia treatment. Although they directly recognize the orthosteric binding site of numerous monoaminergic G protein-coupled receptors (GPCRs), these drugs, and particularly second-generation antipsychotics such as clozapine, all have in common a very high affinity for the serotonin 5-HT2A receptor (5-HT2AR). Using classical pharmacology and targeted signaling pathway assays, previous findings suggest that clozapine and other atypical antipsychotics behave principally as 5-HT2AR neutral antagonists and/or inverse agonists. However, more recent findings showed that antipsychotics may also behave as pathway-specific agonists. Reversible phosphorylation is a common element in multiple signaling networks. Combining a quantitative phosphoproteomic method with signaling network analysis, we tested the effect of clozapine treatment on the overall level of protein phosphorylation and signal transduction cascades in vitro in mammalian cell lines induced to express either the human 5-HT2AR or the H452Y variant of the gene encoding the 5-HT2AR receptor. This naturally occurring variation within the 5-HT2AR gene was selected because it has been repeatedly associated with schizophrenia patients who do not respond to clozapine treatment. Our data show that short time exposure (5 or 10 min) to clozapine (10-5 M) led to phosphorylation of numerous signaling components of pathways involved in processes such as endocytosis, ErbB signaling, insulin signaling or estrogen signaling. Cells induced to express the H452Y variant showed a different basal phosphoproteome, with increases in the phosphorylation of mTOR signaling components as a translationally relevant example. However, the effect of clozapine on the functional landscape of the phosphoproteome was significantly reduced in cells expressing the 5-HT2AR-H452Y construct. Together, these findings suggest that clozapine behaves as an agonist inducing phosphorylation of numerous pathways downstream of the 5-HT2AR, and that the single nucleotide polymorphism encoding 5-HT2AR-H452Y affects these clozapine-induced phosphorylation-dependent signaling networks.

Diagnostic accuracy of IL1ß in saliva: The development of predictive models for estimating the probability of the occurrence of periodontitis in non-smokers and smokers.

AIM: To obtain salivary interleukin (IL) 1ß-based models to predict the probability of the occurrence of periodontitis, differentiating by smoking habit. MATERIALS/METHODS: A total of 141 participants were recruited, 62 periodontally healthy controls and 79 subjects affected by periodontitis. Fifty of the diseased patients were given non-surgical periodontal treatment and showed significant clinical improvement in 2 months. IL1ß was measured in the salivary samples using the Luminex instrument. Binary logistic regression models were obtained to differentiate untreated periodontitis from periodontal health (first modelling) and untreated periodontitis from treated periodontitis (second modelling), distinguishing between non-smokers and smokers. The area under the curve (AUC) and classification measures were calculated. RESULTS: In the first modelling, IL1ß presented AUC values of 0.830 for non-smokers and 0.689 for smokers (accuracy = 77.6% and 70.7%, respectively). In the second, the predictive models revealed AUC values of 0.671 for non-smokers and 0.708 for smokers (accuracy = 70.0% and 75.0%, respectively). CONCLUSION: Salivary IL1ß has an excellent diagnostic capability when it comes to distinguishing systemically healthy patients with untreated periodontitis from those who are periodontally healthy, although this discriminatory potential is reduced in smokers. The diagnostic capacity of salivary IL1ß remains acceptable for differentiating between untreated and treated periodontitis.

Accuracy of single molecular biomarkers in gingival crevicular fluid for the diagnosis of periodontitis: A systematic review and meta-analysis.

AIM: To analyse, by means of a meta-analytical approach, the diagnostic accuracy of molecular biomarkers in gingival crevicular fluid (GCF) for the detection of periodontitis in systemically healthy subjects. MATERIAL AND METHODS: Studies on GCF molecular biomarkers providing a binary classification table (or sensitivity and specificity values and group sample sizes) in individuals with clinically diagnosed periodontitis were considered eligible. The search was performed using six electronic databases. The methodological quality of studies was assessed through the tool Quality Assessment of Diagnostic Studies. Meta-analyses were performed using the Hierarchical Summary Receiver Operating Characteristic, which adjusts classification data using random effects logistic regression. RESULTS: The included papers identified 36 potential biomarkers for the detection of periodontitis and for four of them meta-analyses were performed. The median sensitivity and specificity were for MMP8, 76.7% and 92.0%; for elastase, 74.6% and 81.1%; for cathepsin, 72.8% and 67.3%, respectively. The worst estimates of sensitivity and specificity were for trypsin (71.3% and 66.1%, respectively). CONCLUSIONS: MMP8 showed good sensitivity and excellent specificity, which resulted in this biomarker being clinically the most useful or effective for the diagnosis of periodontitis in systemically healthy subjects, regardless of smoking condition.

Serotonin 2A receptor disulfide bridge integrity is crucial for ligand binding to different signalling states but not for its homodimerization.

The serotonin 2A (5-HT2A) receptor is a G-protein coupled receptor (GPCR) with a conserved disulfide bridge formed by Cys148 (transmembrane helix 3, TM3) and Cys227 (extracellular loop 2, ECL-2). We hypothesized that disulfide bridges may determine serotonin 5-HT2A receptor functions such as receptor activation, functional selectivity and ligand recognition. We used the reducing agent dithiothreitol (DTT) to determine how the reduction of disulfide bridges affects radioligand binding, second messenger mobilization and receptor dimerization. A DTT-induced decrease in the number of binding sites (1190 ± 63.55 fmol/mg protein for control cells compared with 921.2 ± 60.84 fmol/mg protein for DTT-treated cells) as well as in the efficacy of both signalling pathways characterized was observed, although the affinity and potency were unchanged. Bioluminiscence resonance energy transfer (BRET) assays revealed the DTT treatment did not modify the homodimeric nature of serotonin 5-HT2A receptors. In molecular dynamic simulations, the ECL-2 of the receptor with a broken cysteine bond adopts a wider variety of conformations, some of which protrude deeper into the receptor orthosteric binding pocket leading to collapse of the pocket. A shrunken binding pocket would be incapable of accommodating lysergic acid diethylamide (LSD). Our findings suggest that the decrease of efficacy may be due to disruption of disulfide bridge between TM3 and ECL-2. This reveals the integrity of the ECL-2 epitope, which should be explored in the development of novel ligands acting as allosteric modulators of serotonin 5-HT2A receptors.

Composición vegttal, preferencias alimenticias abundancia de biblidinae (lepiidoptera: nymphalidae) en un fragmento de bosque seco tropical en el departamento del atlántico, Colomiia / Plant Composition, Feeding Preferences and Abundance of Biblidinae (Lepidoptera: Nymphalidae) in a Tropical Dry Forest Fragment in the Department of Atlántico, Colombia

Se analizó la variación espacio-temporal de la abundancia de las mariposas de la subfamilia Biblidinae (Lepidoptera: Nymphalidae) en un fragmento de Bs-T en la Reserva Campesina La Montaña (RCM), Atlántico, Colombia; desde enero hasta agosto de 2011. Se marcaron cuatro puntos dentro del área de estudio, donde se ubicaron trampas Van Someren-Rydon cebadas con calamar en descomposición, fruta fermentada y con una mezcla de los anteriores cebos. Adicionalmente, se realizó una caracterización de la vegetación por punto, para lo cual se tomaron datos de diámetro a la altura del pecho (DAP), altura y tamaño de la copa para todas aquellas plantas leñosas con DAP mayor o igual a 2,5 cm. Se capturaron 76 individuos agrupados en seis especies y cuatro géneros; destacándose Hamadryas februa (Hübner) como la más dominante con 32 individuos. El mes de marzo presentó la mayor riqueza y abundancia (6 especies y 25 individuos) durantes las primeras lluvias en la zona. El punto 3 presentó los valores más altos de diversidad y abundancia de Biblidinae (5 especies y 37 individuos) y la mayor densidad de árboles (D= 0,28 individuos/m²). Se demuestra que la estructura de este grupo de mariposas presenta un patrón temporal y espacial en esta reserva. El análisis de componentes principales demostró que el área basal total (ABT) y la Densidad (D) de plantas leñosas, pueden considerarse como un factor determinante en la distribución y abundancia de las especies de la subfamilia Biblidinae en la RCM.

The abundance and spatio-temporal variation of butterflies of the Biblidinae subfamily (Lepidoptera: Nymphalidae) in a fragment of Tropical dry forest at the Reserva Campesina La Montaña (RCM), Atlántico, Colombia; from January until August 2011, was analyzed. Within the study area four points were marked; Van Someren-Rydon traps were placed.in each point using rotten squid, fermented fruit and a mixture of both as bait. In addition, a characterization of the vegetation by point was performed, taking data of the diameter to the breast height (DBH), height and size of treetop of all woody plants with a DBH greater than or equal to 2.5 cm. In total 76 butterfly individuals grouped in six species and four genera were captured; being Hamadryas februa (Hübner) the most dominant with 32 individuals. The greatest richness and abundance was recorded in March (6 species and 25 individuals), during the first rains in the study area. The point 3 presented the highest values of diversity and abundance (five species and 37 individuals) of Biblidinae and the higher density of trees (D= 0,28 individuals/m2). The structure of this butterflies group presents a spatio-temporal pattern in this reserve. The principal components analysis showed that the total basal area (ABT) and the density (D) of woody plants, can be considered a determining factor in the distribution and abundance of species of the subfamily Biblidinae at the RCM.