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Cell Communication and Signaling : CCS Apr 2023Due to the unique nature of spermatozoa, which are transcriptionally and translationally silent, the regulation of capacitation is based on the formation of...
BACKGROUND
Due to the unique nature of spermatozoa, which are transcriptionally and translationally silent, the regulation of capacitation is based on the formation of posttranslational modifications of proteins (PTMs). However, the interactions between different types of PTMs during the capacitation remain unclear. Therefore, we aimed to unravel the PTM-based regulation of sperm capacitation by considering the relationship between tyrosine phosphorylation and reversible oxidative PTMs (oxPTMs), i.e., S-nitrosylation and S-glutathionylation. Since reversible oxPTMs may be closely related to peroxyredoxin (PRDX) activity, the second aim was to verify the role of PRDXs in the PTM-based regulation of capacitation.
METHODS
Cryopreserved bull sperm were capacitated in vitro with or without PRDX inhibitor. Qualitative parameters of sperm and symptoms characteristic of capacitation were analyzed. Posttranslational protein modifications (S-nitrosylation, S-glutathionylation, tyrosine phosphorylation) were investigated at the cellular level (flow cytometry, fluorescence microscopy) and at the proteomic level (fluorescent gel-based proteomic approach).
RESULTS
Zona-pellucida binding proteins (ACRBP, SPAM1, ZAN, ZPBP1 and IZUMO4) were particularly rich in reversible oxPTMs. Moreover, numerous flagellar proteins were associated with all analyzed types of PTMs, which indicates that the direction of posttranslational modifications was integrated. Inhibition of PRDX activity during capacitation caused an increase in S-nitrosylation and S-glutathionylation and a decrease in tyrosine phosphorylation. Inhibition of PRDXs caused GAPDHS to undergo S-glutathionylation and the GSTO2 and SOD2 enzymes to undergo denitrosylation. Moreover, PRDX inhibition caused the AKAP proteins to be dephosphorylated.
CONCLUSIONS
Our research provides evidence that crosstalk occurs between tyrosine phosphorylation and reversible oxPTMs during bull sperm capacitation. This study demonstrates that capacitation triggers S-nitrosylation and S-glutathionylation (and reverse reactions) of zona-pellucida binding proteins, which may be a new important mechanism that determines the interaction between sperms and oocytes. Moreover, TCA-related and flagellar proteins, which are particularly rich in PTMs, may play a key role in sperm capacitation. We propose that the deglutathionylation of ODFs and IZUMO4 proteins is a new hallmark of bull sperm capacitation. The obtained results indicate a relationship between PRDX activity and protein phosphorylation, S-glutathionylation and S-nitrosylation. The activity of PRDXs may be crucial for maintaining redox balance and for providing proper PKA-mediated protein phosphorylation during capacitation. Video Abstract.
Topics: Male; Animals; Cattle; Sperm Capacitation; Proteomics; Semen; Proteins; Protein Processing, Post-Translational; Phosphorylation; Tyrosine
PubMed: 37046330
DOI: 10.1186/s12964-023-01080-w -
Current Topics in Membranes 2018The ability to regulate cell volume is crucial for normal physiology; equally the regulation of extracellular fluid homeostasis is of great importance. Alteration of... (Review)
Review
The ability to regulate cell volume is crucial for normal physiology; equally the regulation of extracellular fluid homeostasis is of great importance. Alteration of normal extracellular fluid homeostasis contributes to the development of several diseases including cystic fibrosis. With regard to the airway surface liquid (ASL), which lies apically on top of airway epithelia, ion content, pH, mucin and protein abundance must be tightly regulated. Furthermore, airway epithelia must be able to switch from an absorptive to a secretory state as required. A heterogeneous population of airway epithelial cells regulate ASL solute and solvent composition, and directly secrete large mucin molecules, antimicrobials, proteases and soluble mediators into the airway lumen. This review focuses on how epithelial ion transport influences ASL hydration and ASL pH, with a specific focus on the roles of anion and cation channels and exchangers. The role of ions and pH in mucin expansion is also addressed. With regard to fluid volume regulation, we discuss the roles of nucleotides, adenosine and the short palate lung and nasal epithelial clone 1 (SPLUNC1) as soluble ASL mediators. Together, these mechanisms directly influence ciliary beating and in turn mucociliary clearance to maintain sterility and to detoxify the airways. Whilst all of these components are regulated in normal airways, defective ion transport and/or mucin secretion proves detrimental to lung homeostasis as such we address how defective ion and fluid transport, and a loss of homeostatic mechanisms, contributes to the development of pathophysiologies associated with cystic fibrosis.
Topics: Epithelial Cells; Homeostasis; Humans; Ion Transport; Mucociliary Clearance; Mucus
PubMed: 30243435
DOI: 10.1016/bs.ctm.2018.08.004 -
Clinical Journal of the American... Aug 2018The secretion of small molecules by the proximal tubules of the kidneys represents a vital homeostatic function for rapidly clearing endogenous solutes and medications... (Review)
Review
The secretion of small molecules by the proximal tubules of the kidneys represents a vital homeostatic function for rapidly clearing endogenous solutes and medications from the circulation. After filtration at the glomerulus, renal blood flow is directed through a network of peritubular capillaries, where transporters of the proximal tubules actively secrete putative uremic toxins and hundreds of commonly prescribed drugs into the urine, including protein-bound substances that cannot readily cross the glomerular basement membrane. Despite its central physiologic importance, tubular secretory clearance is rarely measured or even estimated in clinical or research settings. Major barriers to estimating tubular solute clearance include uncertainty regarding optimal endogenous secretory markers and a lack of standardized laboratory assays. The creation of new methods to measure tubular secretion could catalyze advances in kidney disease research and clinical care. Differences in secretory clearance relative to the GFR could help distinguish among the causes of CKD, particularly for disorders that primarily affect the tubulointerstitium. As the primary mechanism by which the kidneys excrete medications, tubular secretory clearance offers promise for improving kidney medication dosing, which is currently exclusively on the basis of filtration. The differing metabolic profiles of retained solutes eliminated by secretion versus glomerular filtration suggest that secretory clearance could uniquely inform uremic toxicity, refine existing measures of residual kidney function, and improve prediction of cardiovascular and kidney disease outcomes. Interdisciplinary research across clinical, translational, and laboratory medicine is needed to bring this often neglected kidney function into the limelight.
Topics: Bodily Secretions; Humans; Kidney; Kidney Diseases; Kidney Function Tests; Kidney Tubules, Proximal
PubMed: 29490976
DOI: 10.2215/CJN.12001017 -
Nutrients Feb 2021The dietary isothiocyanate L-sulforaphane (LSF), derived from cruciferous vegetables, is reported to have several beneficial biological properties, including...
The dietary isothiocyanate L-sulforaphane (LSF), derived from cruciferous vegetables, is reported to have several beneficial biological properties, including anti-inflammatory and immunomodulatory effects. However, there is limited data on how LSF modulates these effects in human immune cells. The present study was designed to investigate the immunomodulatory effects of LSF (10 µM and 50 µM) on peripheral blood mononuclear cell (PBMC) populations and cytokine secretion in healthy adult volunteers ( = 14), in the presence or absence of bacterial (lipopolysaccharide) and viral (imiquimod) toll-like receptor (TLRs) stimulations. Here, we found that LSF reduced pro-inflammatory cytokines interleukin (IL)-6, IL-1β, and chemokines monocyte chemoattractant protein (MCP)-1 irrespective of TLR stimulations. This result was associated with LSF significantly reducing the proportion of natural killer (NK) cells and monocytes while increasing the proportions of dendritic cells (DCs), T cells and B cells. We found a novel effect of LSF in relation to reducing cluster of differentiation (CD) 14 monocytes while simultaneously increasing monocyte-derived DCs (moDCs: lineage-Human Leukocyte Antigen-DR isotype (HLA-DR)CD11b CD11c). LSF was also shown to induce a 3.9-fold increase in the antioxidant response element (ARE) activity in a human monocyte cell line (THP-1). Our results provide important insights into the immunomodulatory effects of LSF, showing in human PBMCs an ability to drive differentiation of monocytes towards an immature monocyte-derived dendritic cell phenotype with potentially important biological functions. These findings provide insights into the potential role of LSF as a novel immunomodulatory drug candidate and supports the need for further preclinical and phase I clinical studies.
Topics: Adult; Bodily Secretions; Cell Differentiation; Cell Line; Cytokines; Dendritic Cells; Female; Healthy Volunteers; Humans; Immunologic Factors; Immunomodulation; Isothiocyanates; Killer Cells, Natural; Leukocytes, Mononuclear; Male; Sulfoxides
PubMed: 33673203
DOI: 10.3390/nu13020602 -
The Journal of Allergy and Clinical... Nov 2021Increased airway smooth muscle mass is a key pathology in asthma. Bronchial thermoplasty is a treatment for severe asthma based on selective heating of the airways that...
BACKGROUND
Increased airway smooth muscle mass is a key pathology in asthma. Bronchial thermoplasty is a treatment for severe asthma based on selective heating of the airways that aims to reduce the mass of airway smooth muscle cells (ASMCs), and thereby bronchoconstriction. However, short heat exposure is insufficient to explain the long-lasting effect, and heat shock proteins (HSPs) have been suggested to play a role.
OBJECTIVE
We sought to determine the role of HSP70 and HSP90 in the control of airway wall remodeling by bronchial thermoplasty.
METHODS
Bronchoalveolar lavage fluid and endobronchial biopsies of 20 patients with severe asthma were obtained before and after thermoplasty. Isolated epithelial cells and ASMCs were exposed to 65C for 10 seconds, mimicking thermoplasty. Proteins were determined by immunohistochemistry, Western blotting, immunofluorescence, and ELISA; proliferation by cell counts and antigen Ki67 (MKI67) expression.
RESULTS
Thermoplasty significantly increased the expression of HSP70 and HSP90 in the epithelium and bronchoalveolar lavage fluid. In ASMCs, thermoplasty reduced both HSPs. These cell-type-specific effects were detectable even 1 month after thermoplasty in tissue sections. In epithelial cells, ex vivo exposure to heat (65C, 10 seconds) increased the expression and secretion of HSP70 and HSP90. In addition, epithelial cell proliferation was upregulated by heat or treatment with human recombinant HSP70 or HSP90. In ASMCs, heat exposure or exogenous HSPs reduced proliferation and differentiation. In both cell types, HSP70 and HSP90 activated the signaling cascade of serine/threonine-protein kinase →mammalian target of rapamycin→ribosomal protein S6 kinase 1 and CCAAT/enhancer binding protein-β→protein arginine methyltransferase 1→ mitochondria activity.
CONCLUSIONS
Epithelial cell-derived HSP70 and HSP90 improve the function of epithelial cells, but block ASMC remodeling.
Topics: Airway Remodeling; Asthma; Bodily Secretions; Bronchi; Bronchial Thermoplasty; Cells, Cultured; Epithelial Cells; Female; HSP70 Heat-Shock Proteins; HSP90 Heat-Shock Proteins; Humans; Male; Middle Aged; Myocytes, Smooth Muscle; Signal Transduction
PubMed: 33675818
DOI: 10.1016/j.jaci.2021.02.022 -
Microbiology Spectrum Jan 2019Members of the phylum have many unique features, including gliding motility and the type IX protein secretion system (T9SS). gliding and T9SSs are common in, but...
Members of the phylum have many unique features, including gliding motility and the type IX protein secretion system (T9SS). gliding and T9SSs are common in, but apparently confined to, this phylum. Most, but not all, members of the phylum secrete proteins using the T9SS, and most also exhibit gliding motility. T9SSs secrete cell surface components of the gliding motility machinery and also secrete many extracellular or cell surface enzymes, adhesins, and virulence factors. The components of the T9SS are novel and are unrelated to those of other bacterial secretion systems. Proteins secreted by the T9SS rely on the Sec system to cross the cytoplasmic membrane, and they use the T9SS for delivery across the outer membrane. Secreted proteins typically have conserved C-terminal domains that target them to the T9SS. Some of the T9SS components were initially identified as proteins required for gliding motility. Gliding does not involve flagella or pili and instead relies on the rapid movement of motility adhesins, such as SprB, along the cell surface by the gliding motor. Contact of the adhesins with the substratum provides the traction that results in cell movement. SprB and other motility adhesins are delivered to the cell surface by the T9SS. Gliding and the T9SS appear to be intertwined, and components of the T9SS that span the cytoplasmic membrane may energize both gliding and protein secretion. The functions of the individual proteins in each process are the subject of ongoing investigations.
Topics: Adhesins, Bacterial; Bacterial Secretion Systems; Bacteroidetes; Locomotion; Protein Transport
PubMed: 30767845
DOI: 10.1128/microbiolspec.PSIB-0002-2018 -
Current Opinion in Allergy and Clinical... Feb 2018The identification of immunological markers in nasal secretions and tears is becoming essential in the study of allergic diseases. The collection procedure of nasal and... (Review)
Review
PURPOSE OF REVIEW
The identification of immunological markers in nasal secretions and tears is becoming essential in the study of allergic diseases. The collection procedure of nasal and ocular secretions directly influences the results, thus it is of paramount importance to validate and standardize the sampling process.
RECENT FINDINGS
Current techniques for nasal secretions sampling are mainly based on three principles: collection of spontaneous secretions, nasal washings, and absorption. Collection of spontaneous secretions is appropriate in subjects with nasal hypersecretion, whereas in healthy individuals the collected volume is frequently insufficient. Nasal washings are associated with an unpredictable, high dilution and concentrations of markers often fall below detection limits of immunological assays. Absorption seem to provide the best compromise between sufficient sample amounts and detectability of inflammatory mediators and immunoglobulin E. Tear samples can be obtained by glass capillary tubes, filter paper strips and ophthalmic sponges. Volumes are however small or highly diluted through reflex tearing.
SUMMARY
Secretions reflect the local inflammatory activity and provide valuable information about the immunological reaction to allergens at the target organ. There is increasing evidence of the potential clinical role of their analysis, for diagnosis, and monitoring of allergic rhino-conjunctivitis. Appropriate collection and processing is very important and requires special attention.
Topics: Allergy and Immunology; Biomarkers; Bodily Secretions; Conjunctivitis, Allergic; Humans; Immunoglobulin E; Nasal Mucosa; Rhinitis, Allergic; Specimen Handling; Tears
PubMed: 29135513
DOI: 10.1097/ACI.0000000000000412 -
Journal of Dairy Science Apr 2023Corrected milk equations were developed in attempts to bring milk weights to a standardized basis for comparison by expressing the weight and composition of milk as... (Review)
Review
Corrected milk equations were developed in attempts to bring milk weights to a standardized basis for comparison by expressing the weight and composition of milk as corrected to the energy content of milk of a specific composition. Expressed as milk weights familiar on farm and in commerce, this approach integrates energy contributions of the dissimilar components to make the mass units more comparable. Such values are applied in evaluating feed efficiency, lactation performance, and global milk production, as functional units for lifecycle assessments, and in translation of research results. Corrected milk equations are derived from equations relating milk gross energy to milk composition. First, a milk energy equation is used to calculate the energy value of the milk composition to correct to (e.g., 0.695 Mcal/kg for milk with 3.5% fat, 3.05% true protein, and 4.85% lactose). That energy value is divided into the energy equation to give the corrected milk equation. Confusion has arisen, as different equations purport to correct to the same milk composition; their differences are based on uses of different energy equations or divisors. Accuracy of corrected milk equations depends on the accuracy of the energy equations used to create them. Energy equations have evolved over time as different milk component analyses have become more available. Inclusion of multiple milk components more accurately predicts milk energy content than does fat content alone. Omission of components from an equation requires the assumption that their content in milk is constant or highly correlated with an included component. Neither of these assumptions is true. Milk energy equations evaluated on a small data set of measured milk values have demonstrated that equations that incorporate protein, fat, and lactose contents multiplied by the gross energy of each component more closely predict milk energy than equations containing fewer components or regression-derived equations. This provides a tentative recommendation for using energy equations that include the 3 main milk components and their gross energy multipliers for predicting milk energy and deriving corrected milk equations. Accuracy of energy equations is affected by the accuracy of gross energy values of individual components and variability of milk composition. Lactose has consistent reported gross energy values. In contrast, gross energy of milk fat and protein vary as their compositional profiles change. Future refinements could assess accuracy of milk fat and protein gross energy and whether that appreciably improves milk energy predictions. Fat gross energy has potential to be calculated using the milk fatty acid profile, although the influence on gross energy may be small. For research, direct reporting of milk energy values, rather than corrected milk, provides the most explicit, least manipulated form of the data. However, provision of corrected milk values in addition to information on components can serve to translate the energy information to a form familiar to and widely used in the field. When reporting corrected milk data, the corrected milk equation, citation for the energy equation used, and composition and energy contents of the corrected milk must be described to make clear what the values represent.
Topics: Female; Animals; Milk; Lactation; Lactose; Diet; Energy Metabolism; Proteins
PubMed: 36710181
DOI: 10.3168/jds.2022-22219 -
Frontiers in Cellular and Infection... 2022Tick sialome is comprised of a rich cocktail of bioactive molecules that function as a tool to disarm host immunity, assist blood-feeding, and play a vibrant role in... (Review)
Review
Tick sialome is comprised of a rich cocktail of bioactive molecules that function as a tool to disarm host immunity, assist blood-feeding, and play a vibrant role in pathogen transmission. The adaptation of the tick's blood-feeding behavior has lead to the evolution of bioactive molecules in its saliva to assist them to overwhelm hosts' defense mechanisms. During a blood meal, a tick secretes different salivary molecules including vasodilators, platelet aggregation inhibitors, anticoagulants, anti-inflammatory proteins, and inhibitors of complement activation; the salivary repertoire changes to meet various needs such as tick attachment, feeding, and modulation or impairment of the local dynamic and vigorous host responses. For instance, the tick's salivary immunomodulatory and cement proteins facilitate the tick's attachment to the host to enhance prolonged blood-feeding and to modulate the host's innate and adaptive immune responses. Recent advances implemented in the field of "omics" have substantially assisted our understanding of host immune modulation and immune inhibition against the molecular dynamics of tick salivary molecules in a crosstalk between the tick-host interface. A deep understanding of the tick salivary molecules, their substantial roles in multifactorial immunological cascades, variations in secretion, and host immune responses against these molecules is necessary to control these parasites. In this article, we reviewed updated knowledge about the molecular mechanisms underlying host responses to diverse elements in tick saliva throughout tick invasion, as well as host defense strategies. In conclusion, understanding the mechanisms involved in the complex interactions between the tick salivary components and host responses is essential to decipher the host defense mechanisms against the tick evasion strategies at tick-host interface which is promising in the development of effective anti-tick vaccines and drug therapeutics.
Topics: Animals; Immunity; Proteins; Saliva; Ticks
PubMed: 35372098
DOI: 10.3389/fcimb.2022.809052 -
Clinical and Experimental Immunology Nov 2018Dipeptidyl peptidase 4 (DPP4, CD26) is a serine protease that is expressed constitutively by many haematopoietic and non-haematopoietic tissues. It exists as a... (Review)
Review
Dipeptidyl peptidase 4 (DPP4, CD26) is a serine protease that is expressed constitutively by many haematopoietic and non-haematopoietic tissues. It exists as a membrane-associated protein, as well as in an active, soluble form (herein called sDPP4), present at high concentrations in bodily fluids. Despite the proposed use of sDPP4 as a biomarker for multiple diseases, its cellular sources are not well defined. Here, we report that individuals with congenital lymphocyte immunodeficiency had markedly lower serum concentrations of sDPP4, which were restored upon successful treatment and restoration of lymphocyte haematopoiesis. Using irradiated lymphopenic mice and wild-type to Dpp4 reciprocal bone marrow chimeric animals, we found that haematopoietic cells were a major source of circulating sDPP4. Furthermore, activation of human and mouse T lymphocytes resulted in increased sDPP4, providing a mechanistic link between immune system activation and sDPP4 concentration. Finally, we observed that acute viral infection induced a transient increase in sDPP4, which correlated with the expansion of antigen-specific CD8 T cell responses. Our study demonstrates that sDPP4 concentrations are determined by the frequency and activation state of lymphocyte populations. Insights from these studies will support the use of sDPP4 concentration as a biomarker for inflammatory and infectious diseases.
Topics: Animals; Biomarkers; Bodily Secretions; Dipeptidyl Peptidase 4; Disease Models, Animal; Hematopoiesis; Humans; Influenza A virus; Membrane Proteins; Mice; Mice, Inbred C57BL; Mice, Knockout; Orthomyxoviridae Infections; Severe Combined Immunodeficiency; Solubility; T-Lymphocytes; Transplantation Chimera
PubMed: 30251416
DOI: 10.1111/cei.13163