Myocardial proteome changes in aortic stenosis rats subjected to long-term aerobic exercise.

The effects of exercise training (ET) on the heart of aortic stenosis (AS) rats are controversial and the mechanisms involved in alterations induced by ET have been poorly clarified. In this study, we analyzed the myocardial proteome to identify proteins modulated by moderate-intensity aerobic ET in rats with chronic supravalvular AS. Wistar rats were divided into four groups: sedentary control (C-Sed), exercised control (C-Ex), sedentary aortic stenosis (AS-Sed), and exercised AS (AS-Ex). ET consisted of five treadmill running sessions per week for 16 weeks. Statistical analysis was performed by ANOVA or Kruskal-Wallis and Goodman tests. Results were discussed at a significance level of 5%. At the end of the experiment, AS-Ex rats had higher functional capacity, lower blood lactate concentration, and better cardiac structural and left ventricular (LV) functional parameters than the AS-Sed. Myocardial proteome analysis showed that AS-Sed had higher relative protein abundance related to the glycolytic pathway, oxidative stress, and inflammation, and lower relative protein abundance related to beta-oxidation than C-Sed. AS-Ex had higher abundance of one protein related to mitochondrial biogenesis and lower relative protein abundance associated with oxidative stress and inflammation than AS-Sed. Proteomic data were validated for proteins related to lipid and glycolytic metabolism. Chronic pressure overload changes the abundance of myocardial proteins that are mainly involved in lipid and glycolytic energy metabolism in rats. Moderate-intensity aerobic training attenuates changes in proteins related to oxidative stress and inflammation and increases the COX4I1 protein, related to mitochondrial biogenesis. Protein changes are combined with improved functional capacity, cardiac remodeling, and LV function in AS rats.

Salivary proteomic profile of response to different resistance training protocols: A case report.

Resistance training (RT) with blood flow restriction (BFR) or high intensity (HI) are effective to increase muscle mass. To understand this effect, techniques known as "omics" are used to identify possible biomarkers. This study analyzed the salivary proteomic profile of healthy individuals trained before and after two RT protocols both designed with eight exercises for upper- and lower-limbs, one performed at low percentage of one-maximum repetition (%1RM) with BFR technique, and other at high %1RM (HI) without BRF technique. Four healthy males between 18 and 28 years participated in the study. Stimulated saliva was collected before (BBFR/BHI) and immediately after (ABFR/AHI) the two RT protocols. All protein-related processing was performed using label-free proteomic. The difference in expression between groups was expressed as p < .05 for downregulated proteins and 1-p > .95 for upregulated proteins. There was difference in salivary flow between ABFR and BBFR (p = .005). For HI, 87 proteins were found after the practice and 119 before. Three hemoglobin isoforms were increased in AHI compared with BHI. In the BFR comparison, 105 proteins were identified after (ABFR) and 70 before (BBFR). Among those increased ABFR, we highlight five hemoglobin isoforms and Deleted in malignant brain tumors 1 protein. Between ABFR and AHI, 17 isoforms of histones, Transaldolase, Transketolase, Glyceraldehyde-3-phosphate dehydrogenase, and Antileukoproteinase were decreased ABFR. For HI, there was an increase in proteins related to oxidative stress and metabolism of the musculoskeletal system, compared with BFR. HI seems to induce higher anabolic signaling to muscle mass increase and antiatherosclerotic effects.

Interaction of Statherin-Derived Peptide with the Surface of Hydroxyapatite: Perspectives Based on Molecular Dynamics Simulations.

INTRODUCTION: Statherin-derived peptide (StatpSpS) has shown promise against erosive tooth wear. To elucidate its interaction with the hydroxyapatite (HAP) surface, the mechanism related to adsorption of this peptide with HAP was investigated through nanosecond-long all-atom molecular dynamics simulations. METHODS: StatpSpS was positioned parallel to the HAP surface in 2 orientations: 1 - neutral and negative residues facing the surface and 2 - positive residues facing the surface. A system containing StatpSpS without HAP was also simulated as control. In the case of systems with HAP, both partially restrained surface and unrestrained surface were constructed. Structural analysis, interaction pattern, and binding-free energy were calculated. RESULTS: In the peptide system without the HAP, there were some conformational changes during the simulation. In the presence of the surface, only moderate changes were observed. Many residues exhibited short and stable distances to the surface, indicating strong interaction. Specially, the residues ASP1 and SER2 have an important role to anchor the peptide to the surface, with positively charged residues, mainly arginine, playing a major role in the further stabilization of the peptide in an extended conformation, with close contacts to the HAP surface. CONCLUSION: The interaction between StatpSpS and HAP is strong, and the negative charged residues are important to the anchoring of the peptide in the surface, but after the initial placement the peptide rearranges itself to maximize the interactions between positive charged residues.

Hemoglobin Protects Enamel against Intrinsic Enamel Erosive Demineralization.

INTRODUCTION: This study investigated the changes in the acquired enamel pellicle (AEP) proteome when this integument is formed in vivo after treatment with sugarcane-derived cystatin (CaneCPI-5), hemoglobin (HB), and a statherin-derived peptide (StN15), or their combination and then exposed to an intrinsic acid challenge. The effectiveness of these treatments in preventing intrinsic erosion was also evaluated. METHODS: Ten volunteers, after prophylaxis, in 5 crossover phases, rinsed with the following solutions (10 mL, 1 min): control (deionized water-H2O) - group 1, 0.1 mg/mL CaneCPI-5 - group 2, 1.0 mg/mL HB - group 3, 1.88 × 10-5M StN15 - group 4, or a blend of these - group 5. Following this, AEP formation occurred (2 h) and an enamel biopsy (10 µL, 0.01 m HCl, pH 2.0, 10 s) was conducted on one incisor. The biopsy acid was then analyzed for calcium (Arsenazo method). The vestibular surfaces of the other teeth were treated with the same acid. Acid-resistant proteins in the residual AEP were then collected and analyzed quantitatively via proteomics. RESULTS: Compared to control, treatment with the proteins/peptide, mixed or isolated, markedly enhanced acid-resistant proteins in the AEP. Notable increases occurred in pyruvate kinase PKM (11-fold, CaneCPI-5), immunoglobulins and submaxillary gland androgen-regulated protein 3B (4-fold, StN15), Hb, and lysozyme C (2-fold, StN15). Additionally, a range of proteins not commonly identified in the AEP but known to bind calcium or other proteins were identified in groups treated with the tested proteins/peptide either in isolation or as a mixture. The mean (SD, mM) calcium concentrations released from enamel were 3.67 ± 1.48a, 3.11 ± 0.72a, 1.94 ± 0.57b, 2.37 ± 0.90a, and 2.38 ± 0.45a for groups 1-5, respectively (RM-ANOVA/Tukey, p < 0.05). CONCLUSIONS: Our findings demonstrate that all treatments, whether using a combination of proteins/peptides or in isolation, enhanced acid-resistant proteins in the AEP. However, only HB showed effectiveness in protecting against intrinsic erosive demineralization. These results pave the way for innovative preventive methods against intrinsic erosion, using "acquired pellicle engineering" techniques.

Acquired enamel pellicle and biofilm engineering with a combination of acid-resistant proteins (CaneCPI-5, StN15, and Hemoglobin) for enhanced protection against dental caries - in vivo and in vitro investigations.

OBJECTIVE: This study was designed in two-legs. In the in vivo, we explored the potential of a rinse solution containing a combination (Comb) of 0.1 mg/mL CaneCPI-5 (sugarcane-derive cystatin), 1.88 × 10- 5M StN15 (statherin-derived peptide) and 1.0 mg/mL hemoglobin (Hb) to change the protein profile of the acquired enamel pellicle(AEP) and the microbiome of the enamel biofilm. The in vitro, was designed to reveal the effects of Comb on the viability and bacterial composition of the microcosm biofilm, as well as on enamel demineralization. MATERIALS AND METHODS: In vivo study, 10 participants rinsed (10mL,1 min) with either deionized water (H2O-control) or Comb. AEP and biofilm were collected after 2 and 3 h, respectively, after rinsing. AEP samples underwent proteomics analysis, while biofilm microbiome was assessed via 16 S-rRNA Next Generation Sequencing(NGS). In vitro study, a microcosm biofilm protocol was employed. Ninety-six enamel specimens were treated with: 1)Phosphate-Buffered Solution-PBS(negative-control), 2)0.12%Chlorhexidine, 3)500ppmNaF and 4)Comb. Resazurin, colony-forming-units(CFU) and Transversal Microradiography(TMR) were performed. RESULTS: The proteomic results revealed higher quantity of proteins in the Comb compared to control associated with immune system response and oral microbial adhesion. Microbiome showed a significant increase in bacteria linked to a healthy microbiota, in the Comb group. In the in vitro study, Comb group was only efficient in reducing mineral-loss and lesion-depth compared to the PBS. CONCLUSIONS: The AEP modification altered the subsequent layers, affecting the initial process of bacterial adhesion of pathogenic and commensal bacteria, as well as enamel demineralization. CLINICAL RELEVANCE: Comb group shows promise in shaping oral health by potentially introducing innovative approaches to prevent enamel demineralization and deter tooth decay.

Proteomic profile of the acquired enamel pellicle of children with early childhood caries and caries-free children.

Acquired enamel pellicle plays an important role in the pathogenesis of early childhood caries (ECC), working as a protective interface between the tooth and the oral cavity. The aim of this cross-sectional in vivo proteomic study was to compare the acquired enamel pellicle protein profile of 3-5-year-old children with ECC (n = 10) and caries-free children (n = 10). Acquired enamel pellicle samples were collected and processed for proteomic analysis (nLC-ESI-MS/MS). In total, 241 proteins were identified. Basic salivary proline-rich protein 1 and 2, Cystatin-B, and SA were found only in the caries free group. When comparing caries free and ECC groups, lower protein levels were found in the caries free group for hemoglobin subunit beta, delta, epsilon, gamma-2, globin domain-containing protein and gamma-1, neutrophil defensin 3, serum albumin, protein S100-A8, and S100-A9. The proteins histatin-1, statherin, salivary acidic proline-rich phosphoprotein ½, proline-rich protein 4, submaxillary gland androgen-regulated protein 3B, alpha-amylase 1 and 2B were found at higher levels in the caries free group. The exclusive and the proteins found at higher levels in the caries free group might have protective functions that play a role in the prevention of caries, besides providing important insights to be evaluated in future studies for the possible development of new therapeutic strategies for ECC.

Solutions Containing a Statherin-Derived Peptide Reduce Enamel Erosion in vitro.

The effect of solutions containing a statherin-derived peptide (Stn15pSpS) on the protection against enamel erosion in vitro was evaluated. Bovine enamel specimens were divided into 4 groups (n = 15/group): (1) deionized water (negative control), (2) Elmex Erosion Protection™ (positive control), (3) 1.88 × 10-5 M Stn15pSpS, and (4) 3.76 × 10-5 M Stn15pSpS. The solutions were applied on the specimens for 1 min. Stimulated saliva was collected from 3 donors and used to form a 2-h acquired pellicle on the specimens. Then, the specimens were submitted to an erosive pH-cycling protocol 4 times/day, for 7 days (0.01 M HCl pH 2.0/45 s, artificial saliva/2 h, and artificial saliva overnight). The solutions were applied again during pH-cycling, 2 times/day for 1 min after the first and last erosive challenges. Enamel loss (µm) was assessed by contact profilometry. Data were analyzed by Kruskal-Wallis and Dunn's test (p < 0.05). The best protection against erosion was conferred by Elmex Erosion Protection that significantly differed from all the other treatments, followed by the solutions containing Stn15pSpS, regardless of the concentration. However, 3.76 × 10-5 M Stn15pSpS did not differ from the negative control. The solution containing the lower concentration of Stn15pSpS protected against erosion in vitro, which should be confirmed using protocols that more closely resemble the clinical condition.

Different vehicles containing CaneCPI-5 reduce erosive dentin wear in situ.

OBJECTIVE: This study evaluated the protective capacity of a sugarcane-derived cystatin (CaneCPI-5) in different vehicles (1-solution and 2-chitosan gel) against erosive dentin wear in situ. METHODS: In part-1, 15 volunteers participated in a crossover protocol (solutions): Water; Elmex™ and CaneCPI-5. The volunteers wore an appliance with 4 dentin samples for 5 days. These samples were treated with a drop of the solutions for 1 min (4X/d), then the acquired pellicle (AP) was formed and the samples were subjected to erosive challenges (EROSION: citric acid, for 90 s, 4X/day). 2X/day, half of the samples were also abraded for 15 s (ABRASION). In part-2, 16 volunteers participated in a crossover protocol (gel): No gel, Chitosan gel, Chitosan gel + NaF and Chitosan gel + CaneCPI-5. The volunteers also wore an appliance. The samples were treated once/day with the gel or not for 4 min, then the AP was formed and the samples were subjected to erosive and abrasive challenges, as reported in part-1. Dentin wear was measured by profilometry. Data were analyzed by two-way RM-ANOVA and Sidak's tests (p < 0.05). RESULTS: Part-1: Elmex™ and CaneCPI-5 significantly reduced dentin loss in comparison with Water for the EROSION/ABRASION conditions (p < 0.05). Part-2, all the treated groups significantly reduced the dentin loss in comparison to the No gel. The greatest reduction was found for the gel + CaneCPI-5 group for the EROSION/ABRASION (p < 0.05). CONCLUSION: The solution and chitosan gel containing CaneCPI-5 protected against erosive dentin wear in situ. CLINICAL RELEVANCE: These different vehicles are probably sufficient for protecting people with high risk of developing erosive dentin wear.

Teeth with acute apical abscess vs. teeth with chronic apical periodontitis: a quantitative and qualitative proteomic analysis.

OBJECTIVE: To quantitatively and qualitatively analyze the proteomic profile of teeth with acute apical abscesses (AAA) compared with teeth with chronic apical periodontitis (CAP) and to correlate the expression of detected human proteins with their main biological functions. MATERIALS AND METHODS: Samples were obtained from root canals of 9 patients diagnosed with AAA and 9 with CAP. Samples were analyzed by reversed-phase liquid chromatography coupled to mass spectrometry. Label-free quantitative proteomic analysis was performed by Protein Lynx Global Service software. Differences in protein expression were calculated using the t-test (p < 0.05). RESULTS: In total, 246 human proteins were identified from all samples. Proteins exclusively found in the AAA group were mainly associated with the immunoinflammatory response and oxidative stress response. In the quantitative analysis, 17 proteins were upregulated (p < 0.05) in the AAA group, including alpha-1-acid glycoprotein, hemopexin, fibrinogen gamma chain, and immunoglobulin. Additionally, 61 proteins were downregulated (p < 0.05), comprising cathepsin G, moesin, gelsolin, and transketolase. Most of the proteins were from the extracellular matrix, cytoplasm, and nucleus. CONCLUSIONS: The common proteins between the groups were mainly associated with the immune response at both expression levels. Upregulated proteins mostly belonged to the acute-phase proteins, while the downregulated proteins were associated with DNA/RNA regulation and repair, and structural function. CLINICAL RELEVANCE: The host response is directly related to the development of apical abscesses. Thus, understanding the behavior of human proteins against the endodontic pathogens involved in this condition might contribute to the study of new approaches related to the treatment of this disease.

Saliva proteomic profile of early childhood caries and caries-free children.

OBJECTIVE: Saliva plays an important antimicrobial role and it is related to the pathogenesis of early childhood caries (ECC). The aim of this study was to compare the proteomic profile of unstimulated saliva of children aged 3-5 years who had ECC and caries-free (CF) children. MATERIALS AND METHODS: After the saliva collection from 20 children (ECC: n = 10; CF: n = 10), the samples were processed for proteomic analysis on a mass spectrometer. RESULTS: 1638 proteins were identified, of which 355 were present in both groups. A total of 579 proteins were exclusively identified in the CF group and included Leucine-rich alpha-2-glycoprotein, Protein S100-A5, Protein S100-A8 and Mucin-2. Moreover, 704 proteins were exclusively identified in the ECC group, including Enamelin. The differential expression analysis revealed that 112 proteins were up-regulated in the CF group. Among these proteins, we highlighted Hemoglobin subunit gamma-1 (343-fold increase), gamma-2 (336-fold increase) and alpha (40-fold increase). CONCLUSIONS: The proteomic profile of the saliva varied substantially between the groups. Hemoglobin subunit gamma-1, gamma-2 and alpha may play a protective role in children with ECC. These proteins should be evaluated in future studies, because they may be possible good candidates to be included in anti-caries dental products.

Proteomic Study of Broiler Plasma Supplemented with Different Levels of Copper and Manganese from Different Sources.

The aim of the present study was to evaluate the differential expression of plasma proteins in broiler chickens supplemented with different sources (sulfates and hydroxychlorides) and levels of copper (15 and 150 mg kg-1) and manganese (80 and 120 mg kg-1). For this, plasma samples from 40 broiler chickens were used, divided into four experimental groups: S15-80 (15 ppm CuSO4 and 80 ppm MnSO4), S150-120 (150 ppm CuSO4 and 120 ppm MnSO4), H15-80 (15 ppm Cu(OH)Cl and 80 ppm Mn(OH)Cl), and H150-120 (150 ppm Cu(OH)Cl and 120 ppm Mn(OH)Cl). From plasma samples obtained from each bird from the same treatment, four pools were made considering 10 birds per group. Plasma proteome fractionation was performed by 2D-PAGE. Concentrations of the studied minerals were also evaluated in both plasma and protein pellet samples. A higher concentration of Cu and Mn was observed in the plasma and protein pellets of groups that received higher mineral supplementation levels compared to those receiving lower levels. Mn concentrations were higher in plasma and protein pellets of the hydroxychloride-supplemented groups than the sulfate-supplemented groups. Analysis of the gels revealed a total of 40 differentially expressed spots among the four treatments. Supplementation with different sources of minerals, particularly at higher levels, resulted in changes in protein regulation, suggesting a potential imbalance in homeostasis.

Effect of experimental and commercial artificial saliva formulations on the activity and viability of microcosm biofilm and on enamel demineralization for irradiated patients with head and neck cancer (HNC).

The effect of different artificial saliva formulations on biofilm activity and viability, and on enamel demineralization for head and neck cancer (HNC) patients was evaluated. Irradiated enamel samples were treated (1 min) with BioXtra® or with experimental formulations containing carboxymethylcellulose plus inorganic constituents alone (AS) or containing 0.1 mg mL-1 CaneCPI-5 (AS + Cane), 1.0 mg mL-1 hemoglobin (AS + Hb) or combination of both (AS + Cane + Hb). Phosphate-buffered-saline and chlorhexidine (0.12%) were negative and positive control, respectively. Biofilm was produced from the saliva of five male HNC patients, under 0.2% sucrose exposure for 5 days, and daily treated with the formulations (1 min). No significant effects were observed for the different experimental treatments. BioXtra® significantly reduced lactobacilli, demonstrating antibacterial potential for this group. Chlorhexidine was an effective treatment to significantly reduce all parameters, being an important antimicrobial and anticaries agent. Future in vitro studies must be performed using a new approach for the design of the experimental formulations.

Acquired Pellicle Engineering Using a Combination of Organic (Sugarcane Cystatin) and Inorganic (Sodium Fluoride) Components against Dental Erosion.

This study evaluated the combination of a sugarcane cystatin (CaneCPI-5) and sodium fluoride (NaF) in acquired pellicle engineering for the prevention of dental erosion in vitro. Seventy-five human enamel specimens were prepared and divided into 5 treatment groups (n = 15/group): Deionized water (Control); Elmex™ (SnCl2/NaF/AmF); 0.1 mg/mL CaneCPI-5; 500 ppm NaF; and CaneCPI-5+NaF (Combination). The specimens were individually treated (200 µL; 2 min; 37°C), then incubated in human saliva (200 µL; 1 h, at 37°C) for acquired pellicle formation. Afterward, the specimens were submitted to an erosive challenge (1% citric acid [CR], pH 3.6, 10 mL, 2 min, 25 °C). This sequence was conducted 5 times. Percentage of surface microhardness change (%SMC), relative surface reflection intensity (rSRI), and calcium released to the CR were measured and analyzed by one-way ANOVA followed by Tukey's test (p < 0.05). In general, all the treatments (SnCl2/NaF/AmF, CaneCPI-5, NaF, and Combination) significantly protected the enamel when compared the control group. Regarding %SMC and rSRI, the Combination was the most effective treatment, reducing the %SMC significantly (p < 0.01) when compared to all the other treatments, although this difference was not significant in the CR analysis. All treatments demonstrated a protective effect on enamel against dental erosion; however, the combination of CaneCPI-5 with NaF showed a greater protection.

Proteomic analysis of infected root canals with apical periodontitis in patients with type 2 diabetes mellitus: A cross-sectional study.

AIM: This study aimed to quantitatively and qualitatively determine the proteomic profile of apical periodontitis (AP) in type 2 diabetes mellitus (T2DM) patients in comparison with systemically noncompromised patients and to correlate the protein expression of both groups with their biological functions. METHODOLOGY: The sample consisted of 18 patients with asymptomatic AP divided into two groups according to the presence of T2DM: diabetic group-patients with T2DM (n = 9) and control group-systemically healthy patients (n = 9). After sample collection, the root canal samples were prepared for proteomic analysis using reverse-phase liquid chromatography-mass spectrometry. Label-free quantitative proteomic analysis was performed by Protein Lynx Global Service software. Differences in protein expression between groups were calculated using t-test (p < .05). Biological functions were analysed using the Homo sapiens UniProt database. RESULTS: A total of 727 human proteins were identified in all samples. Among them, 124 proteins common to both groups were quantified, out of which 65 proteins from the diabetic group showed significant differences compared with the control: 43 upregulated (p < .05) and 22 downregulated (p < .05) proteins. No significant differences in protein expression were seen for the remaining 59 proteins (p > .05). Most proteins with differences in expression were related to immune/inflammatory response. Neutrophil gelatinase-associated lipocalin, Plastin-2, Lactotransferrin and 13 isoforms of immunoglobulins were upregulated. In contrast, Protein S100-A8, Protein S100-A9, Histone H2B, Neutrophil defensin 1, Neutrophil defensin 3 and Prolactin-inducible protein were downregulated. CONCLUSIONS: Quantitative differences were demonstrated in the expression of proteins common to diabetic and control groups, mainly related to immune response, oxidative stress, apoptosis and proteolysis. These findings revealed biological pathways that provide the basis to support clinical findings on the relationship between AP and T2DM.

Two-year randomized clinical trial of different restorative techniques in non-carious cervical lesions and MMP activity in gingival crevicular fluid.

OBJECTIVES: To evaluate different restorative techniques for non-carious cervical lesions (NCCLs) and the activity of matrix metalloproteinases (MMPs) in gingival crevicular fluid. MATERIALS AND METHODS: Two hundred restorations were performed in 50 patients using resin composite restorative system without (I) and with selective enamel conditioning (II) and resin-modified glass-ionomer cement without (III) and with EDTA pretreatment (IV). Gingival crevicular fluid samples were collected in 15 patients. Restorations were evaluated using USPHS criteria at baseline and after 2 years. Percentages of MMP activity were assessed by zymography as a surrogate outcome. Equality tests of two proportions, logistic regression analysis, survival analysis, ANOVA repeated measures, and Fisher tests were used. RESULTS: No differences in clinical performance were found among groups. Group I had lower retention at 2 years than at baseline. Decreased alpha scores for marginal integrity and marginal discoloration were observed for all groups after 2 years. MMP-2 decreased after 1 year, and its activity increased back to the initial level after 2 years, mainly for groups I, II, and III. MMP-9 increased after 1 year, and it was reduced to the initial level after 2 years, mainly for group I. CONCLUSIONS: All restorative techniques performed similarly in NCCLs after 2 years with initial marginal defect alterations. MMP-2 reestablished its initial levels after 2 years, and MMP-9 had few alterations over time in crevicular fluid. Clinical relevance The different restorative techniques are equally successful in NCCLs after 2 years of clinical functioning and have similar effects on MMPs present in crevicular fluid.

Radiotherapy changes the salivary proteome in head and neck cancer patients: evaluation before, during, and after treatment.

OBJECTIVES: Salivary glands are affected during radiotherapy in the head and neck region, leading to a reduction in salivary flow and changes its composition. Besides negatively affecting the oral soft tissues, this can also lead to dental impairment. Thus, we evaluated the effect of radiotherapy in the proteomic profile of the saliva in patients with head and neck cancer (HNC). MATERIALS AND METHODS: HNC patients had their saliva collected before (BRT), during (2-5 weeks; DRT), and after (3-4 months; ART) radiotherapy. Saliva was also collected from healthy volunteers (control; C). Samples were processed for proteomic analysis. RESULTS: In total, 1055 proteins were identified, among which 46 were common to all groups, while 86, 86, 286, and 395 were exclusively found in C, BRT, DRT, and ART, respectively. Remarkably, alpha-enolase was increased 35-fold DRT compared with BRT, while proline-rich proteins were decreased. ART there was a 16-fold increase in scaffold attachment factor-B1 and a 3-fold decrease in alpha-enolase and several cystatins. When compared with C, salivary proteins of BRT patients showed increases cystatin-C, lysozyme C, histatin-1, and proline-rich proteins CONCLUSION/CLINICAL REVELANCE: Both HNC and radiotherapy remarkably change the salivary protein composition. Altogether, our results, for the first time, suggest investigating alpha-enolase levels in saliva DRT in future studies as a possible biomarker and strategy to predict the efficiency of the treatment. Moreover, our data provide important insights for designing dental products that are more effective for these patients and contribute to a better understanding of the progressive changes in salivary proteins induced by radiotherapy. Graphical abstract.

Preventive effect of chitosan gel containing CaneCPI-5 against enamel erosive wear in situ.

OBJECTIVE: This study evaluated the preventive effect of a chitosan gel containing CaneCPI-5 against enamel erosion and erosion + abrasion in situ. METHODS: Sixteen volunteers participated in a crossover, double-blind protocol, comprising 4 phases: (1) no treatment (Nt); (2) chitosan gel (Cg); (3) chitosan gel + 12,300 ppm NaF (Cg + NaF); and (4) chitosan gel + 0.1 mg/mL CaneCPI-5 (Cg + Cane). Volunteers wore an appliance containing 4 specimens. Once/day, they applied the gel (except for Nt) (4 min/specimen). Erosive challenges were performed extra-orally (0.1% citric acid, 90 s, 4 × /day; ERO). Specimens were also abraded (toothbrush, 15 s/specimen, 2 × /day; ERO + ABR). Enamel wear was assessed by profilometry and relative surface reflection intensity (%SRI). Two-way RM-ANOVA/Sidak's tests and Spearman's correlation were used (p < 0.05). RESULTS: For profilometry, ERO + ABR promoted significantly greater wear when compared with ERO. There was a significant difference among all treatments. The lowest enamel loss occurred for Cg + Cane, followed by Cg + NaF, Cg, and Nt (p < 0.05). The %SRI was significantly lower for ERO + ABR when compared to ERO, only for the Nt group. The greatest %SRI was found for the Cg + NaF and Cg + Cane groups, which did not differ significantly, regardless of the conditions. The lowest %SRI was found for the Nt and Cg groups, which did not differ from each other, regardless of the conditions. The Nt group did not differ significantly from the Cg + NaF (ERO). There was a significant correlation between both analyses. CONCLUSION: The incorporation of CaneCPI-5 in the chitosan gel prevented erosive wear in situ. CLINICAL RELEVANCE: These results open a new perspective for the use of CaneCPI-5 in other application vehicles, such as chitosan gel.

Intrauterine and Postnatal Exposure to High Levels of Fluoride Is Associated with Motor Impairments, Oxidative Stress, and Morphological Damage in the Cerebellum of Offspring Rats.

Fluoride (F) is abundantly present on Earth and plays a beneficial role in human health. However, exposure to high doses of F can be a risk, mainly in endemic fluorosis regions. In light of this, we investigated the effects of F exposure during the intrauterine and postnatal periods of rats, in doses similar to those recommended in drinking water and the levels of F in regions with endemic fluorosis, on the offspring rats' cerebellum. Pregnant rats were divided into three groups: control (received ultrapure water only), 10 mg F/L, and 50 mg F/L for a period of 42 days (21 days gestation and 21 days lactation). At the end of the lactation period, the male pups were evaluated by behavioral tests, morphological markers, and biochemistry assays. The results pointed out that 50 mg F/L exposure during the intrauterine and lactational period of rats is capable of promoting oxidative stress in the cerebellum with a decrease in Purkinje cell density and myelin basic protein compromise, which could be associated with functional motor impairments. In addition, although 10 mg F/L exposure promoted redox alterations, it did not affect other parameters evaluated, highlighting the safe use of F in low doses.

Global Proteomic Profile of Aluminum-Induced Hippocampal Impairments in Rats: Are Low Doses of Aluminum Really Safe?

Hippocampus is the brain area where aluminum (Al) accumulates in abundance and is widely associated with learning and memory. In the present study, we evaluate behavioral, tissue, and proteomic changes in the hippocampus of Wistar rats caused by exposure to doses that mimic human consumption of aluminum chloride (AlCl3) in urban areas. For this, male Wistar rats were divided into two groups: Control (distilled water) and AlCl3 (8.3 mg/kg/day), both groups were exposed orally for 60 days. After the Al exposure protocol, cognitive functions were assessed by the Water maze test, followed by a collection for analysis of the global proteomic profile of the hippocampus by mass spectrometry. Aside from proteomic analysis, we performed a histological analysis of the hippocampus, to the determination of cell body density by cresyl violet staining in Cornu Ammonis fields (CA) 1 and 3, and hilus regions. Our results indicated that exposure to low doses of aluminum chloride triggered a decreased cognitive performance in learning and memory, being associated with the deregulation of proteins expression, mainly those related to the regulation of the cytoskeleton, cellular metabolism, mitochondrial activity, redox regulation, nervous system regulation, and synaptic signaling, reduced cell body density in CA1, CA3, and hilus.

Mercury metalloproteomic profile in muscle tissue of Arapaima gigas from the Brazilian Amazon.

Metalloproteomics is an innovative methodology for identifying of protein-associated mercury. Thus, we analyzed the muscle proteome of Arapaima gigas (pirarucu), collected in the Madeira River of the Brazilian Amazon, to identify protein-associated mercury, with the aim of identifying possible mercury biomarkers in fish muscle tissue. After obtaining the protein pellet, we conducted two-dimensional electrophoresis (2D PAGE) to fractionate the muscle proteome. Total mercury in muscle tissue and protein pellets and mapping of mercury content in protein spots of the 2D PAGE gels was determined using graphite furnace atomic absorption spectrometry (GFAAS). The protein-associated mercury identification was performed using liquid chromatography coupled with sequence mass spectrometry (LC‒MS/MS). Total mercury determinations by GFAAS indicated concentrations on the order of 153 ± 1.90 mg kg-1 and 142 ± 1.50 mg kg-1 (total precipitation of protein fraction) and 139 ± 1.45 mg kg-1 (fractional precipitation of protein fraction) in muscle tissue and protein pellets, respectively. Mercury concentrations in the range of 48 ± 0.90 to 165 ± 3.00 mg kg-1 were found in twelve protein spots. Among the 2D PAGE protein spots, eleven Hg-binding proteins were identified using LC‒MS/MS, which showed characteristics of mercury exposure biomarkers for important metabolic functions, such as five parvalbumin isoforms, triosephosphate isomerase, cofilin 2 (muscle), and fructose-bisphosphate aldolases.