Salivary Factor Research Articles

Disinfection effect of ozonated water on SARS-CoV-2 in the presence of salivary proteins

Ozonated water is expected to be an effective disinfectant for SARS-CoV-2 present on environmental fomites; however, ozone is consumed by organic substances, resulting in attenuation of its effect. SARS-CoV-2 present in saliva can contaminate environmental surfaces; therefore, it is essential to understand the effect of organic substances in saliva on the disinfectant properties of ozonated water. To assess organic factors in saliva and the extent to which they diminish the effect of ozonated water on SARS-CoV-2. Ozonated water was exposed to salivary organic factors and residual ozone concentrations were measured. SARS-CoV-2 was exposed to a salivary factor and virus inactivation by ozonated water was measured. Amylase and mucin consumed ozone in a concentration-dependent manner. Urea did not. Ozonated water appeared to inactivate SARS-CoV-2 within 30 sec. The amount of inactivated SARS-CoV-2 decreased as the protein concentration increased. Virus inactivation was stronger by 1.5 mg/L ozonated water than by 0.5 mg/L ozonated water. This study suggests that the salivary amylase and mucin decay ozone in a concentration-dependent manner, thereby attenuating the disinfection properties of ozonated water for SARS-CoV-2. An increase of the initial amount of ozone can ameliorate the disinfection effect of ozonated water on SARS-CoV-2. Ozone consumption should be taken into consideration for virus infection control. These results provide fundamental information about the effect of ozonated water when used to decontaminate surfaces harbouring SARS-CoV-2 in saliva.

Estimation of Fibroblast Growth Factor-2 Levels in Saliva and Serum of Healthy and Chronic Periodontitis Patients: A Clinico-biochemical Study

Aim: The purpose of this study is to compare the salivary and serum basic fibroblast growth factor (FGF-2) levels in periodontally healthy and periodontitis subjects of varying severity. Further, the role of FGF-2 as a biomarker of periodontal disease was also assessed. Materials and Methods: Saliva and serum samples were collected from a total of 30 patients. The control group consisted of five healthy volunteers. The test group was further divided into three subgroups, each containing five subjects at different stages of periodontal disease (Stages I, II, and III). Periodontal parameters, including clinical attachment level, probing pocket depth, and gingival index, were recorded for all subjects. The FGF-2 content in both saliva and serum samples was measured using enzyme-linked immunosorbent assay. Results: The healthy subjects demonstrated higher mean FGF-2 levels (6.52 ± 2.29 pg/mL) compared to those with periodontitis (4.4 ± 1.38 pg/mL); the salivary FGF-2 levels were observed to be higher among subjects with periodontitis (6.36 ± 1.48 pg/mL) compared to the healthy subjects (3.43 ± 1.47 pg/mL). It was noted that the serum FGF-2 levels were in the following order: healthy subjects (6.52 ± 2.29 pg/mL), severe periodontitis (5.27 ± 2.23 pg/mL), moderate periodontitis (4.03 ± 0.25 pg/mL), and mild periodontitis (3.9 ± 0.49 pg/mL). In the comparison of salivary FGF-2 levels, the following order was observed: severe periodontitis (6.38 ± 0.61 pg/mL), moderate periodontitis (6.61 ± 0.87 pg/mL), mild periodontitis (6.1 ± 2.52 pg/mL), and healthy subjects (3.43 ± 1.47 pg/mL). Conclusions: Within the limitations of the present study, it can be concluded that FGF-2 levels can be used as a diagnostic marker of disease as its levels are remarkably increased in saliva patients having periodontitis.

The human CD47 checkpoint is targeted by an immunosuppressive Aedes aegypti salivary factor to enhance arboviral skin infectivity.

The Aedes aegypti mosquito is a vector of many infectious agents, including flaviviruses such as Zika virus. Components of mosquito saliva have pleomorphic effects on the vertebrate host to enhance blood feeding, and these changes also create a favorable niche for pathogen replication and dissemination. Here, we demonstrate that human CD47, which is known to be involved in various immune processes, interacts with a 34-kilodalton mosquito salivary protein named Nest1. Nest1 is up-regulated in blood-fed female A. aegypti and facilitates Zika virus dissemination in human skin explants. Nest1 has a stronger affinity for CD47 than its natural ligand, signal regulatory protein α, competing for binding at the same interface. The interaction between Nest1 with CD47 suppresses phagocytosis by human macrophages and inhibits proinflammatory responses by white blood cells, thereby suppressing antiviral responses in the skin. This interaction elucidates how an arthropod protein alters the human response to promote arbovirus infectivity.

The Role of Salivary Vascular Endothelial Growth Factor A, Cytokines, and Amino Acids in Immunomodulation and Angiogenesis in Breast Cancer.

In this work, we focused on the analysis of VEGF content in saliva and its relationship with pro-inflammatory cytokines and amino acids involved in immunomodulation and angiogenesis in breast cancer. The study included 230 breast cancer patients, 92 patients with benign breast disease, and 59 healthy controls. Before treatment, saliva samples were obtained from all participants, and the content of VEGF and cytokines in saliva was determined by an enzyme-linked immunosorbent assay, as well as the content of amino acids by high-performance liquid chromatography. It was found that VEGF was positively correlated with the level of pro-inflammatory cytokines IL-1β (r = 0.6367), IL-6 (r = 0.3813), IL-8 (r = 0.4370), and IL-18 (r = 0.4184). Weak correlations were shown for MCP-1 (r = 0.2663) and TNF-α (r = 0.2817). For the first time, we demonstrated changes in the concentration of VEGF and related cytokines in saliva in different molecular biological subtypes of breast cancer depending on the stage of the disease, differentiation, proliferation, and metastasis to the lymph nodes. A correlation was established between the expression of VEGF and the content of aspartic acid (r = -0.3050), citrulline (r = -0.2914), and tryptophan (r = 0.3382) in saliva. It has been suggested that aspartic acid and citrulline influence the expression of VEGF via the synthesis of the signaling molecule NO, and then tryptophan ensures tolerance of the immune system to tumor cells.

Evaluation of salivary placental growth factor in Health and Periodontitis

BackgroundVarious immune mediators have a role in the progression of periodontitis. Placental Growth Factor (PLGF) is important during pregnancy and also is involved in the pathology of several diseases. Hence, this study aimed to evaluate salivary PLGF in health and periodontitis that seemingly has not been reported earlier.MethodsFifty participants were grouped as healthy and periodontitis patients. Clinical history, periodontal parameters [Plaque Index (PI), Gingival Index (GI), probing pocket depth (PPD), clinical attachment loss (CAL), bleeding on probing (BoP)] were recorded; saliva was collected and PLGF was estimated using a commercially available ELISA kit. The data were statistically analyzed using Shapiro-Wilk’s test, Kruskal-Wallis test, Dunn’s post hoc test with Bonferroni correction, and Spearman’s rank-order correlation coefficient. The significance level was set at p ≤ 0.05 for all tests.ResultsSalivary PLGF levels comparison between the two groups showed no significant difference between both groups. Quantitatively, females had higher salivary PLGF levels than males. No significant association was observed between salivary PLGF levels and the severity of periodontitis. The periodontitis group showed statistically significant correlations between salivary PLGF levels, BoP(p = 0.005) and PPD(p = 0.005), and significant correlations of PLGF with PPD (p = 0.035) for both groups.ConclusionsPLGF can be detected and measured in the saliva of healthy individuals and periodontitis patients. However, the role of PLGF in periodontal pathology needs to be further confirmed based on their salivary levels.

Evaluation of salivary tumor necrosis factor α as a diagnostic biomarker in oral submucosal fibrosis and squamous cell carcinoma of the oral cavity and oropharynx: a cross sectional observational study.

Tumor necrosis factor α (TNF-α) is known to be associated with chronic inflammation, and its expression has been shown to increase in advanced cancers. Chronic inflammation is a characteristic feature of oral submucous fibrosis (OSMF), which is a potentially malignant disorder (PMD). Squamous cell carcinoma (SCC) is associated with considerable mortality and morbidity and an early detection or monitoring would greatly help in achieving an effective cure. TNF-α was thus evaluated for use as a biomarker in the present study according to the stage of OSMF and histological grade of SCC in the oral cavity and oropharynx. This study included 45 patients divided into 3 groups-OSMF group, SCC group and control group-each comprising 15 participants. Saliva samples were collected from each patient, and salivary TNF-α levels were estimated using an ELISA kit. Statistical analysis revealed no significant differences in TNF-α levels among the OSMF, SCC and control groups; however, there was an increase in the salivary TNF-α level in patients with stage 3 disease according to the clinical stage of OSMF, for which the p value was 0.027. An increase in the TNF-α concentration with increasing clinical stage suggested a role for TNF-α in the spread of OSMF involvement in anatomical structures of the oral cavity and oropharynx. No significant difference in salivary TNF-α levels was noted among the OSMF, SCC and control groups. The study showed a positive correlation of TNF-α with increasing stages of OSMF but was not a reliable biomarker in the categorization of the same.

The effect of curcumin oral gel on radiation-induced oral mucositis in relation to salivary epidermal growth factor

Background: Radiation-induced oral mucositis (RIOM) poses a significant challenge in the management of head and neck cancer patients (HNCs). Patients may require adjustments in their cancer treatment, such as dose reductions or treatment delays, which can decrease the effectiveness of the antineoplastic therapy. Numerous clinical investigations have demonstrated that curcumin, an herbal agent, exhibits a wide range of pharmacologic actions, including anti-inflammatory, antibacterial, and anticarcinogenic effects and the ability to enhance wound healing. Objectives: To evaluate the effect of curcumin oral gel with the magic solution (dexamethasone-based mouthwash) as a standard mouthwash treatment for RIOM in relation to salivary epidermal growth factor (EGF) before and after radiation therapy. Methods: Thirty-one HNCs who received radiotherapy with a head and neck mask were divided into the curcumin oral gel and the magic-solution groups. Saliva samples were collected before radiation, at the 3rd week of radiation, and post-radiation. Salivary EGF was measured using an enzyme-linked immunosorbent assay. RIOM was assessed using both the WHO and the VAS scales. Results: Significant differences were found between both groups in the WHO scale (P = 0.027) and VAS score (P = 0.047). Patients who used oral curcumin gel presented with less severe RIOM and elevated salivary EGF levels during the radiation sessions. Conclusion: Curcumin oral gel might be an effective agent in preventing and managing RIOM, as evidenced by the observed increase in salivary EGF.

Salivary Brain-Derived Neurotrophic Factor and Cortisol Associated with Psychological Alterations in University Students.

Recent evidence reported mental health issues in university students such as anxiety and depressive symptoms and poor sleep quality. Decreased plasma brain-derived neurotrophic factor (BDNF) levels have been proposed as a biomarker of depressive symptoms, whereas cortisol levels are an index of energy mobilization and stress and have been linked to sleep quality. Given that salivary biomarkers represent an interesting new field of research, the aim of this cross-sectional study was to evaluate salivary BDNF and cortisol levels in university students to assess whether they have associations with psychological disturbances such as anxiety and depressive symptoms, sleep quality, and stress level. Salivary BDNF and cortisol levels were measured by specific immunoassays in 70 students whose mental health was also evaluated on the same day through the evaluation of anxiety and depression symptoms (Goldberg scale), sleep quality (Pittsburg Sleep Quality Index and Athens Insomnia Scale), and stress (self-perceived stress scale) and healthy lifestyle habits (alcohol consumption, smoking, regular exercise, and body mass index) were also measured. Multivariate regression analyses were performed in order to identify the strengths of associations between psychological alterations and the concentrations of BDNF, cortisol, and other variables. Salivary BDNF levels were significantly higher in students with more depressive symptoms, whereas no significant differences were found for cortisol levels. When performing the binary logistic regression model, BDNF levels are included as a predictor variable for a high-depressive-symptoms burden (p < 0.05). Students with worse sleep quality on the Pittsburg Scale had higher cortisol levels (p < 0.05). The subdomains of sleep latency and sleep medication were those significantly associated with salivary cortisol levels in logistic regression analyses (OR = 15.150, p = 0.028). Sleep medication only appeared to be related to cortisol levels (OR = 185.142, p = 0.019). Perceived stress levels and anxiety symptoms were not associated with BDNF or cortisol levels. BDNF could play a key role in the pathophysiology of mood-related disorders, and elevation of its peripheral levels could contribute to protecting neurons from the development of mental illness. Higher salivary cortisol levels measured in the morning are accompanied by poorer sleep quality. More research is needed, focusing on salivary biomarkers of disorders related to depressive symptoms and poor sleep quality as a potential tool for the diagnosis and prevention of mental illness.

Salivary and crevicular fluid proinflammatory cytokines and advanced glycation end products in patients with different glycemic levels undergoing fixed orthodontic treatment.

To examine whether patients with different blood glycemic levels undergoing fixed orthodontic therapy demonstrate changes in the biochemical profiles of crevicular fluid and salivary advanced glycation end products (AGEs) and proinflammatory cytokine levels in comparison with nondiabetic healthy subjects. Prediabetic subjects, subjects with type 2 diabetes mellitus (T2DM), and subjects without a diabetes mellitus diagnosis undergoing fixed orthodontic therapy with MBT prescription brackets (0.022-inch brackets and 0.019 × 0.025-inch stainless steel archwires) were included in the study. The following clinical periodontal parameters were evaluated: (1) plaque score (PS), (2) probing depth (PD), (3) bleeding on probing (BOP), and (4) clinical attachment loss. Crevicular fluid and saliva specimens were collected during regular orthodontic visits. Salivary and crevicular fluid tumor necrosis factor alpha, interleukin-6, ghrelin, resistin, AGEs, and receptor activator of nuclear factor κΒ ligand were evaluated using a human magnetic Luminex multiplex assay. BOP scores were significantly higher among T2DM subjects (19.2%) than among nondiabetic subjects (11.2%) and prediabetic subjects (15.9%). Comparable values were demonstrated by all three study groups regarding PD scores and PSs. T2DM subjects demonstrated higher scores for gingival crevicular fluid (GCF) chemokines than nondiabetic and prediabetic subjects. A statistically significant difference was found in the levels of AGEs and resistin among the three study groups. The scores revealed for the levels of GCF resistin and AGEs versus periodontal BOP demonstrated a significant positive association by the Pearson correlation test. T2DM patients demonstrated significantly higher levels of GCF resistin and AGEs during fixed orthodontic therapy. Chronic hyperglycemic patients undergoing orthodontic therapy demonstrated a proinflammatory response.

Association between salivary mature brain-derived neurotrophic factor and psychological distress in healthcare workers.

Previous studies have suggested association between brain-derived neurotrophic factor (BDNF) and the stress level of workers. However, no studies have investigated the potential of salivary mature BDNF (mBDNF) level as a noninvasive biomarker for psychological distress. This study aimed to explore the reliability of salivary mBDNF as a biomarker for psychological distress in healthcare workers. Furthermore, we examined the relationship between salivary and plasma mBDNF levels and their correlation with age, sex, body mass index (BMI), and exercise habits. Fifty-one healthy healthcare workers (26 men) from the University of Occupational and Environmental Health, Japan, participated in this study. In this cross-sectional study, participants provided demographic information. Psychological distress was assessed using the Kessler 6 (K6). Saliva and blood samples were collected, and mBDNF was measured by ELISA. Spearman's rank correlation coefficient was performed to analyze the relationship between mBDNF (saliva and plasma) and K6. Statistical analyses were conducted using Stata 17.0, and a significance level of p<.05 was applied. The median K6 score was 1 (interquartile range [IQR]: 0-3). The median (IQR) salivary mBDNF was 1.36 (1.12-1.96)pg/mL, whereas the mean (standard deviation) plasma mBDNF was 1261.11 (242.98)pg/mL. No correlation was observed between salivary and plasma mBDNF concentrations or with the K6 score. Additionally, there were no associations between salivary or plasma mBDNF concentrations and age, sex, or exercise habits. Finally, an association between plasma mBDNF concentration and BMI was found only in univariate analysis. Our findings indicate that salivary mBDNF can be accurately measured noninvasively in healthcare workers. Within our study sample, salivary mBDNF did not demonstrate any correlation with K6 and plasma mBDNF. Future studies with a larger study sample and a diverse study population consisting of healthy participants and patients with psychiatric disorders are warranted.

Salivary Trefoil Factor (TFF3) in Stage I–II Periodontitis: A Prospective Clinical Study

Abstract Objective This article evaluates the salivary trefoil factor levels using enzyme-linked immunosorbent assay and clinical parameters in stage I to II periodontitis subjects. Materials and Method A total of 44 subjects with periodontitis and healthy periodontium were enrolled for the study as per the inclusion criteria. The subjects were selected and categorized as group A (control group) and group B (test group). Scaling was performed on healthy subjects at baseline and 1 month if necessary and scaling and root planing was performed for periodontitis subjects. Trefoil factor 3 (TFF3) levels was analyzed at first and post-nonsurgical periodontal therapy followed by clinical parameters, respectively. Statistical Analysis Inferential statistics were performed using independent t-test and repeated measures of analysis of variance (ANOVA) test. Independent t-test was used for the intergroup comparison of all the variables. Repeated measures of ANOVA test along with post hoc Bonferroni test was used for the intragroup comparison and the level of statistical significance was set at 0.001. Results Difference in TFF3 levels and clinical parameters was seen between groups A and B, which was statistically significant. Conclusion Within the constraints of the study, it can be stated that TFF3 is a relevant biomarker to determine the activity and association of periodontal and systemic diseases, gastrointestinal disorders, and inflammatory bowel diseases.

Salivary trefoil factor family peptide 3 (TFF3) and flow rate in persons with and without obstructive sleep apnea: A preliminary study.

Obstructive sleep apnea (OSA) is one of the most common chronic diseases. Trefoil factor family 3 (TFF3) peptides are secreted by major and minor salivary glands and may be involved in the pathogenesis of OSA. This study aimed to evaluate salivary TFF3 and flow rate between those with and without OSA. This was a prospective experimental study that enrolled patients with OSA and non-OSA. Total unstimulated saliva was collected, the salivary flow rate was measured, and theTFF3 level was analyzed by using a modified sandwich enzyme-linked immunosorbent assay. Baseline characteristics, TFF3 level, and salivary flow rate were compared between both groups. Factors associated with theTFF3 level and flow rate were computed by using multivariate linear regression analysis. Twenty-eight participants were recruited in the study: 20 patients with OSA (71.42%) and 8 non-OSA as control. The TFF3 and salivary flow rates between both groups of non-OSA versusOSA were comparable (TFF3 non-OSA 61.06 vs.OSA 96.00 ng/mg; p = .276 and flow rate non-OSA0.40 vs. OSA 0.35 mL/min; p = .320). Factors associated with theTFF3 level were neck circumference with a negative coefficient of -16.419 (p = .042). For the salivary flow rate, only age was a significant factor with the coefficient of -0.013 (p = .044). TFF3 and salivary flow rate were comparable between patients with OSA and non-OSA.The factor associated with TFF3 level was neck circumference, while age was negatively associated with the salivary flow rate in patients with OSA.

Clinical and laboratory phenotype of postcovid asthenic syndrome in children of primary school age

Objective. To determine the clinical and laboratory features of the postcovid syndrome in children of primary school age.&#x0D; Materials and methods. The analysis of complaints and anamnesis, somatic and neurological status in 24 children who had a new coronavirus infection was carried out; the results were also analyzed according to the Subjective Asthenia Scale (version for parents), the Quality of Life Assessment Scale (version for children), the Waynes questionnaire and scheme, the functional status scale. The concentration of monocytic chemotactic factor in the saliva was determined using enzyme immunoassay.&#x0D; Results. Most of the children presented astheno-vegetative complaints, which were confirmed by the MFS scores, and the Wayne's questionnaire and scheme. The concentration of monocytic chemotactic protein in the examined cohort of children was 32.48 23.22 pg/ml, with no significant difference by sex. The level of physical functioning by the quality of life scale was significantly higher in boys (100.00 0.00 points) than in girls (82.03 15.46 points, p = 0.02). A correlation was obtained between the salivary monocyte chemotactic protein content and the scores obtained using the Wayne questionnaire and scheme, as well as the MFS and functional status scales.&#x0D; Conclusions. Vegetative and asthenic syndromes are closely related to the concentration of salivary monocyte chemotactic factor.

Correlations between the severity of radiation-induced oral mucositis and salivary epidermal growth factor as well as inflammatory cytokines in patients with head and neck cancer.

This study aimed to investigate correlations of the severity of radiation-induced oral mucositis (RIOM) with epidermal growth factor (EGF) and inflammatory cytokines in patients with head and neck cancer (HNC). Levels of inflammatory cytokines and EGF in saliva of HNC patients were measured. Correlations of inflammatory cytokines and EGF levels with RIOM severity and pain degree, and their diagnostic values on RIOM severity were determined. Elevated IFN-γ, TNF-α, IL-2, and IL-6 levels, and reduced IL-4, IL-10, and EGF levels were found in patients with severe RIOM. IFN-γ, TNF-α, IL-2, and IL-6 were positively correlated with RIOM severity, while IL-10, IL-4, and EGF were negatively correlated with it. All factors were effective in predicting the severity of RIOM. IFN-γ, TNF-α, IL-2, and IL-6 in saliva of patients with HNC are positively correlated with the severity of RIOM, and IL-4, IL-10, and EGF were negatively correlated with it.

Assessment of attention, memory, and salivary brain-derived neurotrophic factor in chronic smokers: A cross-sectional observational study

Assessment of attention, memory, and salivary brain-derived neurotrophic factor in chronic smokers: A cross-sectional observational study

Differences in salivary secretion and epidermal growth factor concentrations in mild reflux esophagitis and non-erosive reflux disease.

Sex differences in salivary secretion have been reported among healthy subjects. In the present study, salivary secretion and salivary epidermal growth factor (EGF) concentrations were investigated in mild reflux esophagitis patients, non-erosive reflux disease (NERD) patients, and healthy controls by matching the sex ratio. Thirty-three (male:female = 11:22) patients with NERD, 33 (11:22) with mild reflux esophagitis, and 33 (11:22) healthy controls were recruited for this case-control study. Salivary secretion was assessed as follows: each patient chewed sugar-free gum for 3min prior to endoscopy, and the amount of saliva secretion, salivary pH, and salivary pH after acid loading as an index of the acid-buffering capacity were measured. Salivary EGF concentrations were measured by ELISA. No significant differences were observed in the amount of saliva secretion, salivary pH, or the acid-buffering capacity between the mild reflux esophagitis and NERD groups. However, the amount of saliva secretion and the acid-buffering capacity in the mild reflux esophagitis group and the amount of saliva secretion, salivary pH, and the acid-buffering capacity in the NERD group were significantly lower than those in the healthy control group. No significant differences were noted in salivary EGF concentrations between the mild reflux esophagitis and NERD groups. After matching the sex ratio, the saliva secretion was significantly lower in patients with mild reflux esophagitis and NERD than in healthy controls. However, no significant differences were observed in the amount of saliva secretion or salivary EGF concentrations between both groups.

Effect of mechanical instrumentation with adjunct photodynamic therapy on salivary TNFα levels and clinical periodontal and peri‑implant status in patients with depression: A randomized controlled trial

IntroductionThe aim of the present randomized controlled trial was to assess the effect of mechanical instrumentation (MI) with adjunct photodynamic therapy (PDT) on salivary tumor necrosis factor-alpha (TNFα) levels and clinical periodontal and peri‑implant status in patients with depression. Materials and methodsIn groups 1 and 2, individuals with periodontal and peri‑implant diseases with and without depression, respectively were included. Group-3 comprised of systemically healthy individuals with a healthy periodontal and peri‑implant status. In groups 1 and 2, patients in the test- and control groups received MI with and without PDT respectively. Periodontal and peri‑implant probing depth and plaque and gingival indices were measured. Radiographic evaluation was done at baseline. Whole salivary tumor necrosis factor alpha (TNFα) in peri‑implant sulcular fluid were measured at baseline. The clinical and immunological parameters were reassessed at 120 days’ follow-up. Level of significance was set at P<0.05. ResultsThirty-four, 36 and 37 implants were in function in groups 1, 2 and 3, respectively. At baseline, periodontal and peri‑implant clinical parameters and TNFα levels were significantly higher in groups 1 (P<0.05) and 2 (P<0.05) than Group-3. At 4-months follow-up, there was no difference in periodontal and peri‑implant clinical parameters in the test- and control groups among individuals in groups 1 and 3. In Group-2, there was a significant reduction in periodontal (P<0.05) and peri‑implant (P<0.05) clinical parameters at 4-months follow-up than baseline. In Group-2, there was no significant difference in these parameters among patients in the test- and control-groups. ConclusionIn patients with depression clinical periodontal and peri‑implant status is poorer and salivary TNFα levels are higher after MI with or without PDT. In healthy patients, PDT offers no additional benefits in the treatment of periodontal inflammation.

A salivary factor binds a cuticular protein and modulates biting by inducing morphological changes in the mosquito labrum

The mosquito proboscis is an efficient microelectromechanical system, which allows the insect to feed on vertebrate blood quickly and painlessly. Its efficiency is further enhanced by the insect saliva, although through unclear mechanisms. Here, we describe the initial trigger of an unprecedented feedback signaling pathway in Aedes mosquitoes affecting feeding behavior. We identified LIPS proteins in the saliva of Aedes mosquitoes that promote feeding in the vertebrate skin. LIPS show a new all-helical protein fold constituted by two domains. The N-terminal domain interacts with a cuticular protein (Cp19) located at the tip of the mosquito labrum. Upon interaction, the morphology of the labral cuticle changes, and this modification is most likely sensed by proprioceptive neurons. Our study identifies an additional role of mosquito saliva and underlines that the external cuticle is a possible site of key molecular interactions affecting the insect biology and its vector competence.

Salivary Neurotrophins Brain-Derived Neurotrophic Factor and Nerve Growth Factor Associated with Childhood Obesity: A Multiplex Magnetic Luminescence Analysis.

Obesity is linked with higher inflammatory markers and is characterized by chronic low-grade inflammation. Neurotrophins brain-derived neurotrophic factor (BDNF) and β-nerve growth factor (β-NGF), in addition to their neuronal functions, act on several immune cells and have been recently designated as metabokines due to their regulatory role in energy homeostasis and food intake. The current study evaluates the salivary BDNF and β-NGF and their association with anthropometric measurement, blood pressure, and salivary insulin in children. Anthropometric measurements and saliva samples were obtained from 76 children, aged 6–10 years. Multiplex analysis was carried out for the salivary analysis of BDNF, NGF, and insulin by human magnetic Luminex performance assay. Statistical analysis was performed to analyze the best fit diagnostic value for biomarkers and the relationship of the neurotrophic levels of BDNF and NGF with obesity measures and blood pressure. Salivary BDNF and β-NGF showed a significantly higher concentration in obese children than normal-weight children. Both neurotrophins are positively associated with obesity anthropometric measures, blood pressure, and salivary insulin. Multinominal regression analysis reported a significant association between salivary BDNF, β-NGF, insulin, and systolic pressure adjusted for age, gender, income, and maternal education. The salivary concentration of BDNF and NGF was higher in obese children, and it is positively associated with anthropometric measures, suggesting that neurotrophins can be used as a non-invasive predictor of obesity-related complications in children.

Effective Oral RNA Interference (RNAi) Administration to Adult Anopheles gambiae Mosquitoes.

RNA interference has been a heavily utilized tool for reverse genetic analysis for two decades. In adult mosquitoes, double-stranded RNA (dsRNA) administration has been accomplished primarily via injection, which requires significant time and is not suitable for field applications. To overcome these limitations, here we present a more efficient method for robust activation of RNAi by oral delivery of dsRNA to adult Anopheles gambiae. Long dsRNAs were produced in Escherichia coli strain HT115 (DE3), and a concentrated suspension of heat-killed dsRNA-containing bacteria in 10% sucrose was offered on cotton balls ad-libitum to adult mosquitoes. Cotton balls were replaced every 2 days for the duration of the treatment. Use of this method to target doublesex (a gene involved in sex differentiation) or fork head (which encodes a salivary gland transcription factor) resulted in reduced target gene expression and/or protein immunofluorescence signal, as measured by quantitative Real-Time PCR (qRT-PCR) or fluorescence confocal microscopy, respectively. Defects in salivary gland morphology were also observed. This highly flexible, user-friendly, low-cost, time-efficient method of dsRNA delivery could be broadly applicable to target genes important for insect vector physiology and beyond.