Search Results (241)

Xerostomia, the subjective complaint of a dry mouth, is frequently associated with salivary flow reduction and/or salivary gland hypofunction. This condition significantly impacts an individual’s quality of life and oral health, including difficulties in speaking, chewing, and swallowing. Xerostomia may be caused by autoimmune diseases, xerogenic medications, and radiation therapy. Our objective was to identify differentially expressed proteins in the saliva of patients with medication and autoimmune disease-associated xerostomia compared to non-xerostomic control subjects. Two groups of individuals (N = 45 total) were recruited: non-xerostomic subjects (NX-group; n = 18) and xerostomic patients (XP-group; n = 27). Dried saliva spot samples were collected from major salivary glands, i.e., parotid (left and right) and submandibular glands. Proteomic analysis was performed by deep nanoLC-MS/MS. Differential protein expression in the XP-group relative to the NX-group was determined by the Mann–Whitney U-test with FDR Benjamini–Hochberg correction (p_adj < 0.05). The Search Tool for Recurring Instances of Neighboring Genes (STRING_v12.0) was used to generate interaction networks and perform pathway analysis. A total of 1407 proteins were detected. Of these, 86 from the left parotid gland, 112 from the right parotid gland, and 73 from the submandibular gland were differentially expressed proteins (DEPs). Using STRING analysis, we identified, for the first time, several neurodegenerative disease-associated networks, primarily involving the downregulation of the 20S proteasome core complex and glyoxalase proteins across salivary glands. In this study, we determined neuronal dysregulation and impaired methylglyoxal (MGO) detoxification, possibly through reduced protein expression of glyoxalase Parkinson’s Disease (PD) Protein 7 (encoded by the PARK7 gene) in major salivary glands of xerostomic patients. Indeed, impaired MGO detoxification has been previously shown to cause salivary gland dysfunction in a mouse model of type 2 diabetes. Based on other DEPs associated with neurodegenerative disorders, our results also suggest a possible deficiency in the parasympathetic nervous system innervation of salivary glands, warranting further investigation. Full article

Background: Aquaporins (AQPs) are integral membrane proteins that facilitate water transport across biological membranes. While their role is well-characterized in various tissues, their function in the oral cavity remains poorly understood. Saliva is an easily accessible, non-invasive biofluid that contains stable extracellular RNA and can reflect both systemic and local physiological or pathological processes, making it a promising source for RNA analyses. This study investigates AQP mRNA levels in human saliva. Methods: Saliva samples were collected from patients of a dental practice and analyzed using quantitative PCR to detect AQP levels. An in silico analysis of AQPs in cells of the oral cavity were performed. Baseline data of the patients were recorded. Results: Our findings demonstrate the presence of multiple AQP subtypes in human saliva. AQP5 was the most abundant, followed by AQP9 and AQP1. The levels of several AQPs showed intercorrelation, whereas AQP3 appeared to be independently regulated and did not correlate with the other AQPs. Conclusions: This study demonstrates that differential AQP mRNA levels can be detected in human saliva. These findings suggest that salivary AQP mRNA may serve as surrogate markers for altered AQP levels in cells of the oral cavity. In the future, such patterns of AQP levels could potentially be used to identify or monitor pathological conditions affecting the oral mucosa or salivary glands. Further studies are required to validate this approach and to understand its diagnostic relevance. Full article

Human cytomegalovirus (CMV) is the leading cause of congenital infections, often leading to mental retardation and neurological disorders. It is a major public health priority to develop a vaccine for preventing and controlling human CMV infection. In this report, we generated an oral Salmonella-based vaccine to express the M33 protein of murine cytomegalovirus (MCMV) and investigated the anti-MCMV immune responses induced in mice immunized with this vaccine. Compared to those administered with phosphate-buffered saline (PBS) or a control vaccine without M33 expression, mice immunized with the vaccine expressing the M33 protein exhibited a remarkable induction of antiviral serum IgG and mucosal IgA humoral responses and a significant elicitation of antiviral T cell responses. Successful inhibition of viral growth in lungs, spleens, livers, and salivary glands was also found in the vaccinated animals compared to the PBS-treated animals or those immunized with the control vaccine without M33 expression. Furthermore, substantial protection against MCMV challenge was observed in mice immunized with the vaccine. Thus, Salmonella-based vaccine expressing MCMV M33 can induce anti-MCMV effective immune responses and protection. Our study implies that attenuated Salmonella expressing human CMV antigens, including its homologue to M33, may represent promising oral anti-CMV vaccine candidates. Full article

Sjögren’s disease (SjD) is an autoimmune disease of exocrine tissues. Prior research has shown that ETS proto-oncogene 1 (ETS1), STAT1, and IL33 may contribute to the disease’s pathology. However, the regulatory mechanisms of these genes remain poorly characterized. Our objective was to explore the mechanisms of SjD pathology and to identify dysfunctional regulators of these genes by immunostimulation of SjD and sicca relevant cell lines. We used immortalized salivary gland epithelial cell lines (iSGECs) from Sjögren’s disease (pSS1) and sicca (nSS2) patients, previously developed in our lab, and control cell line A253 to dose with immunostimulants IFN-γ or poly(I:C) (0 to 1000 ng/mL and 0 to 1000 µg/mL, respectively) over a 72 h time course. Gene expression was determined using qRT-PCR delta-delta-CT method based on glyceraldehyde-3-phosphate dehydrogenase (GAPDH) for mRNA and U6 small nuclear RNA 1 (U6) for miRNA, using normalized relative fold changes 48 h post-immunostimulation. Protein expression was quantified 72 h post-stimulation by Western blotting. Reference-based RNA-seq of immunostimulated pSS1 and nSS2 cells was performed to characterize the reactome of genes conserved across all used doses. The expression of ETS1 and STAT1 protein was upregulated (p < 0.05) in IFN-γ-treated pSS1 and nSS2, as compared to A253 cells. IFN-γ-treated nSS2 cell showed significant IL33 upregulation. Also, IL33 had a correlated (p < 0.01) U-shaped response for low-mid-range doses for IFN-γ- and poly(I:C)-treated pSS1 cells. RNA-seq showed 175 conserved differentially expressed (DE) genes between nSS2 and pSS1 immunostimulated cells. Of these, 44 were shown to interact and 39 were more abundant (p < 0.05) in pSS1 cells. Western blotting demonstrated nSS2 cells expressing ETS1 uniformly across treatments compared to pSS1 cells, despite similar mRNA abundance. miR-145b and miR-193b were significantly under-expressed in IFN-γ-treated nSS2 cells compared to pSS1 cells (p < 0.01). ETS1 and IL33 showed disproportionate mRNA and protein abundances between immunostimulated Sjögren’s disease-derived (pSS1), and sicca-derived (nSS2) cell lines. Such differences could be explained by higher levels of miR-145b and miR-193b present in pSS1 cells. Also, RNA-seq results suggested an increased sensitivity of pSS1 cells to immunostimulation. These results reflect current pathobiology aspects, confirming the relevance of immortalized salivary gland epithelial cell lines. Full article

Compounds in sand fly saliva elicit specific immune responses that may play a role in the establishment of canine Leishmania infection. Although canine antibodies to anti-sand fly saliva antigens have been extensively studied, little is known about cellular immune responses against Phlebotomus perniciosus salivary proteins. This study aimed to explore humoral and T-cell-mediated immunity against P. perniciosus salivary proteins in dogs (n = 85) from Mallorca (Spain), a leishmaniosis-endemic area, and find correlations with demographic (age, sex, and breed) and parasite-specific immunological parameters. Anti-sand fly saliva IgG was examined using a P. perniciosus whole salivary gland homogenate (SGH) ELISA and recombinant salivary protein rSP03B ELISA. Interferon gamma (IFN-γ) release whole blood assays with L. infantum soluble antigen (LSA), SGH, and rSP03B were also performed. Positive correlations were found between IgG levels in the SGH and rSP03B tests and between concentrations of SGH IFN-γ and rSP03B IFN-γ. While concentrations of SGH IFN-γ and rSP03B IFN-γ were low and produced only by a minority of dogs (less than 20%), high levels and frequencies of LSA IFN-γ as well as anti-saliva IgG for SGH and rSP03B were detected in a majority of dogs (61% and 75%, respectively). LSA IFN-γ levels were positively correlated with age and Leishmania-specific antibodies. In conclusion, dogs from a leishmaniosis-endemic area presented high humoral immunity against P. perniciosus salivary proteins, but their cellular immunity to these proteins was low and less frequent. Full article

Salivary gland cancers (SGCs) pose a therapeutic challenge due to their aggressive nature and limited treatment options. Ion transporters, particularly the sodium/iodide symporter (SLC5A5), which transport iodine in the form of iodide anion (I⁻) into cells, have emerged as potential therapeutic targets in tumors of glandular origin. Our research indicates that SLC5A5 is expressed predominantly in ductal cells of human and murine SGC cells. We assessed the effects of potassium iodide (KI), a source of iodide ions. KI treatment reduced SGC cell proliferation and viability without impacting migration. KI increased ROS levels and triggered caspase-dependent apoptosis, as indicated by the upregulation of the pro-apoptotic protein BAX, downregulation of the anti-apoptotic protein Bcl-2, and induction of SGC cell shrinkage. KI did not affect NF-κB or TNF-α and SLC5A5 expression. Adding the antioxidant N-acetylcysteine reversed KI-induced growth inhibition, underscoring ROS-induced oxidative stress’s crucial role in growth inhibition. While KI administered in drinking water to mice increased epidermal growth factor (EGF) expression in non-malignant salivary gland tissues, KI decreased EGF receptor (EGFR) expression in malignant SGC cell cultures, where EGFR signaling is frequently dysregulated in SGCs but promoted AKT phosphorylation. Combining KI and anti-EGFR treatment did not yield synergistic anti-SGC cell effects. The study underscores the therapeutic potential of KI as a standalone treatment in vitro for SGC cells. However, the upregulation of EGF in non-malignant tissues and, therefore, the possibility to enhance EGFR-driven signals and AKT phosphorylation after KI treatment in cancer patients could indicate a risk of rendering SGC cells more drug resistant, warranting further investigation to optimize its clinical application. Full article

Though a variety of methods are used to conduct West Nile virus (WNV) surveillance, accurate prediction and prevention of outbreaks remain a global challenge. Previous studies have established that the concentration of antibodies to mosquito saliva is directly related to the intensity of exposure to mosquito bites and can be a good proxy to determine risk of infection in human populations. To assess exposure characteristics and transmission dynamics among avian communities, we tested the levels of IgY antibodies against whole salivary glands of Aedes albopictus and Culex quinquefasciatus, as well as WNV antigen, in 300 Northern cardinals sampled from April 2019 to October 2019 in St. Tammany Parish, Louisiana. Though there were no significant differences in antibody responses among sex or age groups, exposure to Ae. albopictus bites was more positively associated with exposure to WNV compared with Cx. quinquefasciatus exposure (ρ = 0.2525, p < 0.001; ρ = 0.1752, p = 0.02437). This association was more pronounced among female birds (ρ = 0.3004, p = 0.0075), while no significant relationship existed between exposure to either mosquito vector and WNV among male birds in the study. In general, two seasonal trends in exposure were found, noting that exposure to Ae. albopictus becomes less intense throughout the season (ρ = −0.1529, p = 0.04984), while recaptured birds in the study were found to have increased exposure to Cx. quinquefasciatus by the end of the season (ρ = 0.277, p = 0.0468). Additionally, we report the identification of several immunogenic salivary proteins, including D7 family proteins, from both mosquito vectors among the birds. Our results suggest that Ae. albopictus may have a role in early-season transmission of WNV, particularly among brooding females and hatchling cardinals. However, bloodmeal analysis was not included in this work and further studies are needed to verify this assumption. Yet, broad circulation of WNV in nesting avian communities could enhance risk of infection among Cx. quinquefasciatus mosquitoes in the late season, with the potential to contribute to human disease incidence and epizootic spillover in the environment. Full article

Klotho, an anti-aging protein, has been extensively studied in systemic conditions such as chronic kidney disease and cardiovascular disorders. In recent years, its pivotal protective role and clinical significance in various oral and maxillofacial diseases have been increasingly demonstrated. It has been demonstrated that Klotho regulates oxidative stress, apoptosis, inflammation, and fibrosis via multiple molecular signaling pathways, including Nrf2, NF-κB, PI3K/Akt/FoxO1, insulin/IGF-1, FGF/FGFR, and Wnt/β-catenin. Consequently, these regulatory effects have been observed in conditions such as periodontitis, oral squamous cell carcinoma, malignant salivary gland tumors, oral submucous fibrosis, etc. Moreover, the decreased expression or dysfunctional activity of Klotho is frequently associated with the onset and progression of these diseases. This study provides a comprehensive review of the underlying mechanisms and recent advances in Klotho research within the realm of oral and maxillofacial diseases, offering novel perspectives for future basic and clinical investigations. Full article

Drosophila has provided a highly attractive model system for studying various tissue- and stage-specific processes as well as their pathologies, including a range of human diseases. The existence of a large number of diverse Gal4 drivers to precisely control the expression patterns of UAS transgenes simplifies such studies. However, the choice of driver is always critical, as its possible ectopic expression in non-target cells and tissues can directly impact the results. Therefore, it is very important to thoroughly characterize both the molecular nature and expression pattern of each Gal4 driver line. Here, we aim to fill such gaps regarding the AB1-Gal4 driver, which is typically used to express UAS transgenes in larval salivary glands. In this fly line, the P{GawB} enhancer trap construct encoding the Gal4 protein resides within overlapping evolutionary conserved spastin (spas) and Mitochondrial Rho (Miro) genes. Both these genes are expressed in a number of tissues, including the central nervous system (CNS), and their human orthologs are associated with neurodegenerative diseases. Consistently, we demonstrate that, in third-instar larvae, the expression pattern of AB1-Gal4 is also not restricted to salivary glands. We detect its activity in a subset of Elav-positive neurons in the CNS, including motor neurons, as well as in specific photoreceptor cells in eye discs. Full article

Nectins constitute a family of Ca(2+)-independent immunoglobulin-like adhesion molecules. They are involved in cell proliferation, morphogenesis, growth, development, and immune modulation. Due to their broad involvement in physiological processes, extensive research is being conducted on the expression of individual nectins in a variety of cancers and their potential in diagnosis, prognosis, and treatment. The overexpression of nectin-1 may be a poor prognostic factor in gastrointestinal cancers (intestine and pancreas). Similarly, the overexpression of nectin-2 is a worse prognostic factor (greater tumor advancement and shorter patient survival) in cancers such as gallbladder, esophagus, and breast cancer. Changes in nectin-3 expression also affect the advancement of, e.g., colorectal cancer. Additionally, a significant factor here seems to be the change in the localization of nectin-3 expression within cellular structures. The most extensively studied nectin-4 also shows prognostic potential in many cancers. Most often, its high expression correlates with poor prognosis (e.g., gastric cancer), but it may also be a positive prognostic factor, e.g., in salivary gland cancer. Therapy based on nectin-4 is already known and used in the case of urothelial cancers. The expression of nectin-like protein 5 (necl-5) also shows prognostic and therapeutic potential in pancreatic and lung cancers, as well as in multiple myeloma. Full article

Attenuated Salmonella strains are promising oral vectors for vaccination against human infectious diseases. Human cytomegalovirus (CMV) is among the most common causes of disability in children, including intellectual disability and sensorineural hearing loss. Developing an anti-CMV vaccine is a major public health priority. We report in this study the construction of a new attenuated Salmonella strain to express murine cytomegalovirus (MCMV) M25 protein and its use for vaccination in mice against MCMV infection. In mice orally vaccinated with the constructed Salmonella vector carrying the M25 expression cassette, we revealed a substantial induction of anti-MCMV serum IgG and mucosal IgA humoral responses and a considerable elicitation of anti-MCMV T cell responses. When the vaccinated mice were challenged intraperitoneally and intranasally with MCMV, we observed a significant inhibition of virus infection and growth in various organs including spleens, livers, lungs, and salivary glands, compared to the non-vaccinated animals or those receiving a control vaccine without M25 protein expression. Moreover, we showed effective protection of these vaccinated mice from MCMV challenge. Our study provides the first direct evidence that an attenuated Salmonella-based vector with the MCMV M25 expression cassette can induce strong humoral and T cell responses and provide effective protection against MCMV infection. These results illustrate the feasibility of engineering Salmonella-based vectors expressing the M25 antigen for anti-CMV oral vaccine development. Full article

Background and Objectives: Type 2 Diabetes Mellitus (T2DM) is a metabolic disease caused by the failure of the skeletal muscle, liver and adipose tissue to respond to insulin. Metformin is the first choice for the treatment of T2DM. Isthmin 1 (Ism1) is a newly discovered adipokine that affects all carbohydrate, lipid and protein metabolism. This study examines the changes in serum and salivary levels of Ism1 in patients using metformin, considering its potential as a follow-up marker for T2DM if present in the salivary glands. Materials and Methods: The study included 30 newly diagnosed T2DM patients and 30 non-diabetic controls. Ism1 was measured by ELISA in serum and saliva after 3 months and compared with routine biochemical parameters. Immunostaining of Ism1 was performed in salivary glands. Results: Ism1 was immunohistochemically detected in salivary glands for the first time. Serum Ism1 levels increased significantly after 3 months of metformin treatment (p = 0.028). The increase in salivary Ism1 levels did not reach statistical significance. Fasting plasma glucose (FPG) (p < 0.001), HbA1c (p < 0.001) and LDL (p = 0.015) levels decreased with metformin. There was a significant negative correlation between the increase in Ism1 levels and the decrease in LDL levels (rho = −0.362, p = 0.05). Conclusions: Despite its first detection in salivary glands, the hypothesis that Ism1 may be a surveillance marker in T2DM could not be confirmed. The negative correlation of Ism1 with LDL levels suggests that Ism1 may contribute to the ameliorative effect of metformin on serum lipids. Further studies are needed to support this conclusion. Full article

The cattle tick, Rhipicephalus microplus, is the most significant ectoparasite in the cattle industry. The application of acaricides constitutes the main control method. However, inadequate treatments have serious drawbacks, including the appearance of multi-resistant ticks. Tick vaccines offer a safe and economically sustainable alternative for controlling R. microplus. Nevertheless, the efficacy of existing vaccines has been limited by polymorphisms in target antigens among strains from different geographical regions. In this study, we characterized a putative Metalloprotease from the ADAMTSL family. We analyzed three regions to evaluate their transcriptional profiling in different R. microplus tick tissues, using two constitutive genes (β-tubulin and Elfa-1) as references. The expression levels showed that ADAMTSL-R1 was upregulated 39.37-fold (p ≤ 0.05) in salivary glands. The ADAMTSL-R2 showed the highest expression, rising 7.69-fold (p ≤ 0.05) in ovaries and up to 59.39-fold (p ≤ 0.05) in egg mass. Furthermore, this region showed the highest level of conservation among Rhipicephalus isolates. The ADAMTSL-R3 was upregulated only in the egg mass. The results of this study provide a basis for future research focused on elucidating the role of these protein variants in tick biology, including their feeding mechanisms and potential implications in pathogen transmission. Understanding these factors may aid in developing an effective tick vaccine. Full article

Background: Human cytomegalovirus (CMV) is the most common cause of viral congenital infections worldwide. The development of effective vaccines against human CMV infection and disease is a high priority. Attenuated Salmonella are attractive oral vaccine vectors against human diseases because they can be administrated orally. Methods: In this study, an attenuated Salmonella strain was generated as an oral vaccine vector for the delivery and expression of the M78 protein of murine cytomegalovirus (MCMV). Using the MCMV infection of mice as the CMV infection model, we characterized the immune responses and protection induced by the constructed Salmonella-based vaccine. Results: The generated Salmonella-based vaccine, v-M78, which contained an M78 expression plasmid construct, carried out gene transfer efficiently for M78 expression and showed little pathogenicity and virulence in mice. In orally vaccinated mice, v-M78 induced anti-MCMV serum IgG and mucosal IgA responses and also elicited anti-MCMV T cell responses. Furthermore, mice immunized with v-M78 were protected from intraperitoneal and intranasal challenges with MCMV. The v-M78 vaccination reduced the titers of the challenged viruses in spleens, livers, lungs, and salivary glands. Conclusions: These results provide the first direct evidence that a Salmonella-based vaccine expressing M78 elicits strong humoral and cellular immune responses and induces immune protection against MCMV infection. Furthermore, our study demonstrates the potential of using Salmonella-based oral vaccines against CMV infection. Full article

H. longicornis is used as an experimental animal model for the study of three-host ticks due to its special life cycle and easy maintenance in the laboratory and in its reproduction. The life cycle of H. longicornis goes through a tightly regulated life cycle to adapt to the changing host and environment, and these stages of transition are also accompanied by proteome changes in the body. Here, we used the isobaric tags for a relative and absolute quantification (iTRAQ) technique to systematically describe and analyze the dynamic expression of the protein and the molecular basis of the proteome of H. longicornis in seven differential developmental stages (eggs, unfed larvae, engorged larvae, unfed nymphs, engorged nymphs unfed adults, and engorged adults). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of the differentially expressed proteins (DEPs) were used. In our study, A total of 2044 proteins were identified, and their expression profiles were classified at different developmental stages. In addition, it was found that tissue and organ development-related proteins and metabolism-related proteins were involved in different physiological processes throughout the life cycle through the GO and KEGG analysis of DEPs. More importantly, we found that the up-regulated proteins of engorged adult ticks were mainly related to yolk absorption, degradation, and ovarian development-related proteins. The abundance of the cuticle proteins in the unfed stages was significantly higher compared with those of the engorged ticks in the previous stages. We believe that our study has made a significant contribution to the research on H. longicornis, which is an important vector of SFTSV. In this study, we identified changes in the proteome throughout the H. longicornis development, and functional analysis highlighted the important roles of many key proteins in developmental events (ovarian development, the molting process, the development of midgut, the development and degeneration of salivary glands, etc.). The revelation of this data will provide a reference proteome for future research on tick functional proteins and candidate targets for elucidating H. longicornis development and developing new tick control strategies. Full article