Search Results (100)

Piscirickettsia salmonis is one of the most significant pathogens affecting salmon farming. Besides liver, head kidney and spleen, skeletal muscle has shown transcriptional immune responses to these bacteria, but the contribution of non-coding RNAs remains poorly understood. This study investigates the role of long non-coding RNAs (lncRNAs) in the immune response of rainbow trout skeletal muscle and primary myotube cultures infected with P. salmonis. Using RNA-seq data from both in vivo and in vitro muscle under control and infected conditions, the analysis identified 4263 candidate lncRNAs through a stringent bioinformatics pipeline. These lncRNAs were mostly classified as exonic and intergenic, showing distinct genomic distributions and structural differences depending on the source. Expression analyses revealed that cell type had a stronger effect on lncRNA profiles than infection status. From 764 differentially expressed lncRNAs, 191 were uniquely associated with infected and 180 with control conditions, mainly unannotated. Functional predictions based on co-expression and proximity to coding genes suggest that lncRNAs are primarily involved in downregulation of structural-cellular maintenance under control conditions, whereas during infection, they are related to immunity, signaling, and apoptosis. Overall, the findings indicate that lncRNAs exhibit origin-specific regulatory roles and are modulated by P. salmonis infection, highlighting their potential importance in fish immune responses. Full article

Porcine group A rotavirus (PoRVA) is a significant cause of viral diarrhea in piglets, necessitating urgent global implementation of effective control strategies. This review assesses advancements in PoRVA in vitro cultivation and amplification, crucial for PoRVA vaccine development. Traditional PoRVA cultivation commonly employs primary porcine kidney cells or finite cell lines like MA-104, posing well-documented challenges in scalability, production cost, and their ability to recapitulate the natural intestinal microenvironment. Consequently, research has increasingly focused on adapting PoRVA to alternative systems, particularly immortalized porcine cell lines or physiologically relevant porcine intestinal organoids. This adaptation process, involving serial passaging, can induce genomic alterations and virulence attenuation in piglets, essential for generating live attenuated vaccine (LAV) candidates. Modern biotechnological tools, such as reverse genetics and synthetic genomics, have expedited the creation of recombinant PoRVA strains with defined antigenic profiles and enhanced in vitro growth characteristics. However, a significant concern regarding LAV candidates derived from cell culture adaptation is the risk of virulence reversion upon pig back-passage, necessitating thorough safety and genetic stability evaluations. Nevertheless, utilizing stable cell lines or organoid platforms presents a feasible and cost-effective approach for large-scale PoRVA vaccine production. Future research should focus on identifying vaccine candidates that provide broad protection and exceptional safety, with an emphasis on cross-protection against divergent epidemic genotypes, while ensuring the economic feasibility of innovative manufacturing approaches. Full article

Diabetic kidney disease (DKD) is a primary cause of end-stage renal disease (ESRD), and while ferroptosis is known to contribute to DKD pathogenesis, the regulatory role of the NLRP3 inflammasome in this process remains elusive. To address this research gap, we explored whether NLRP3 inhibition alleviates DKD by suppressing ferroptosis using streptozotocin-induced diabetic wild-type and NLRP3-knockout C57BL/6 mice, alongside high-glucose-cultured (30 mM) human renal tubular epithelial (HK-2) cells with or without siNLRP3 transfection. Inflammatory cytokines (IL-6, TNF-α, and IL-1β) were measured using an ELISA; oxidative stress markers (CSSG, MDA, GSH, and ROS) and the iron ion content via colorimetric assays; mitochondrial morphology by transmission electron microscopy (TEM); and ferroptosis-related proteins (ACSL4, COX2, and GPX4) through Western blotting. Our findings demonstrate that NLRP3-knockout diabetic mice displayed markedly reduced urinary albumin excretion and serum creatinine levels (p < 0.01) compared with wild-type diabetic controls, concurrent with suppressed renal iron overload and ferroptosis, diminished inflammatory cytokine levels, and attenuated oxidative stress. Pathological assessments further revealed ameliorated renal fibrosis and preserved mitochondrial ultrastructure in NLRP3-deficient mice. In vitro, siNLRP3 transfection abrogated high-glucose-induced inflammation, oxidative stress, and ferroptosis in HK-2 cells, effects that were reversed by the ferroptosis inducer erastin (p < 0.01). Mechanistically, NLRP3 deficiency was associated with upregulated GPX4 expression and downregulated ACSL4 and COX2 expression. Collectively, these results indicate that inhibition of the NLRP3 inflammasome mitigates DKD progression by suppressing ferroptosis, underscoring its translational potential as a therapeutic target for this condition. Full article

This study aimed to elucidate the key characteristics of the humoral immune response and the tissue distribution of specific antibody-secreting cells (ASCs) in Nile tilapia (Oreochromis niloticus). A specific immune model was established by immunizing fish with human IgG. Lymphocytes were isolated from the head kidney, spleen, and peripheral blood and subjected to antigen stimulation in vitro. The MTT assay, reflecting cell metabolic activity and viability, identified the optimal culture conditions as a cell concentration of 2.5 × 10⁶ cells/mL, an antigen concentration of 2 μg/mL, and a culture duration of 72 h. Under these conditions, peripheral blood lymphocytes exhibited the most increase in metabolic activity, followed by head kidney lymphocytes, while splenic lymphocytes showed no significant response. Subsequent dynamic monitoring of antibody-secreting cells (ASCs) using ELISPOT revealed that, in the absence of antigen stimulation, ASC numbers from all three tissues declined over time. Notably, head kidney ASCs retained approximately 50% of their initial number by day 5, whereas ASCs in peripheral blood and spleen decayed to barely detectable or completely undetectable levels, respectively. These findings suggest that the head kidney may serve as a primary site for ASC persistence during the effector phase, potentially contributing to sustained humoral immunity. Although antigen stimulation did not induce significant ASC expansion, it significantly slowed their decay rate (p < 0.05), indicating an antigen-dependent maintenance role. ELISA detection of antibody levels in the culture supernatants showed a consistent trend with the ELISPOT results, further confirming the sustained functional support of antigen for ASCs. Additionally, LPS stimulation experiments demonstrated that all three tissues contained plasmablasts activatable by non-specific stimuli, with peripheral blood showing the highest proliferation fold (4–6 times). In conclusion, this study provides insights into the tissue-specific distribution, in vitro persistence, and antigen-dependent maintenance of ASCs in Nile tilapia, providing insights into the cellular basis that may contribute to humoral immune memory and laying a theoretical foundation for the rational design and application of tilapia vaccines. Full article

Deleterious crosstalk between the gut and distant organs is a key factor behind disease progression. Currently, the molecular signals mediating this communication remain elusive. We hypothesized that systemic oxidative stress and oxidatively modified serum proteins transmit injury signals from extraintestinal sites to the gut. In various murine models of organ injury, primary damage was consistently associated with systemic oxidative stress and intestinal damage. Specifically, ischemia/reperfusion (I/R)-induced acute kidney injury caused profound colonic barrier defects. Depleting the microbiota with antibiotics markedly improved survival and attenuated both renal and colonic injury, implicating translocated microbes in exacerbating pathology. Mechanistically, these changes were linked to systemic oxidative stress and were largely prevented by the antioxidant N-acetylcysteine. Furthermore, serum from I/R mice disrupted epithelial barrier integrity and induced cell death in vitro, effects that were recapitulated by exposure to oxidized serum proteins. Characterization of serum components identified albumin as the predominantly oxidized protein, which displayed potent cytotoxicity toward cultured intestinal epithelial cells. Our findings establish oxidative stress and oxidized serum albumin as key pathogenic factors mediating the detrimental interaction between remote organs and the gut. These data suggest that targeting oxidative modifications offers a promising therapeutic strategy to disrupt this pathological loop in critical illness. Full article

The SARS-CoV-2 papain-like protease (PL^pro) is an essential viral enzyme that promotes viral polyprotein processing while simultaneously suppressing the host innate immune response, which makes it a primary target for developing antiviral drugs. The present study employs a comprehensive approach integrating untargeted metabolomic profiling, in silico molecular docking and dynamics simulations, Molecular Mechanics Generalized Born Surface Area (MM-GBSA) energetic assessments, and biochemical enzyme assays. This integrated method aims to discover natural PL^pro inhibitors from two ethnomedicinal plants, Lippia javanica and Acorus calamus, which have long been utilized in African traditional medicine to treat respiratory diseases. Comprehensive metabolite profiling using untargeted Ultra-Performance Liquid Chromatography–Tandem Mass Spectrometry (UPLC-MS/MS) and Global Natural Products Social (GNPS) molecular networking revealed flavonoid glucuronides and phenylpropanoid derivatives as the major constituents in both plant species. In situ histochemical staining further offered spatial validation of phenolic- and lignin-associated tissues, supporting the phenolic-dominated molecular families detected by GNPS molecular networking. In silico evaluation of six selected compounds demonstrated spontaneous and thermodynamically favorable binding to PL^pro, with ΔG_bind values ranging from −5.63 to −6.43 kcal/mol. Catechin-7-glucoside emerged as the lead compound, establishing multiple hydrogen bond networks with Asp164, Gln269, Tyr264, and Asn267, supplemented by hydrophobic engagement with Pro247 and Pro248, and π-π stacking with the blocking loop 2 (BL2 loop). Molecular dynamics simulations confirmed the stability of the protein–ligand complexes. Biochemical enzyme assays confirmed concentration-dependent inhibition of PL^pro proteolytic and deubiquitinating activity by both crude plant extracts and isolated bioactive compounds. However, S-adenosyl-methionine showed comparatively high PL^pro proteolytic activity (IC₅₀ 5.872 µM) compared to catechin-7-glucoside, with an IC₅₀ of 7.493 µM, exhibiting efficacy similar to the reference inhibitor GRL0617. Both the extracts of L. javanica and A. calamus have shown significant inhibitory activity while maintaining cell viability in Human embryonic kidney 293T cell (HEK293T) culture models, indicating a favorable safety profile of the tested concentrations. Based on these results, catechin-based polyphenols and phenylpropanoid derivatives appear as promising lead compounds for the development of PL^pro inhibitors. To progress toward therapeutic use, further work is necessary in pharmacokinetics, structural optimization, and antiviral validation in cell models. Full article

This study presents the first documented case of a disease syndrome in cultured largefin longbarbel catfish (Hemibagrus macropterus). The condition is characterized by massive abdominal pseudotumor formation, severe cachexia, and functional gonadal arrest. Comprehensive pathological investigation revealed that the pseudotumor was encapsulated by fibroblasts and primarily composed of host-derived, poorly differentiated hyperplastic cells, interspersed with invasive, basophilic Type III cells. These cells and associated inflammatory–fibrotic lesions were also disseminated in the gill, kidney and spleen. Systematic diagnostic approaches, including microbiology and transmission electron microscopy, found no evidence of conventional bacterial or viral pathogens. Metagenomic analysis further supported these findings and suggested a link to infection by an as-yet-unidentified eukaryotic parasite, with Microsporidia or Ichthyosporea being the primary candidates. Functional (KEGG) profiling of the pseudotumor tissue further revealed a molecular signature consistent with active cellular proliferation and metabolism. We propose that the pseudotumor acts as a metabolically active “nutrient sink,” driving the systemic catabolism that underlies the severe cachexia and reproductive arrest. This work provides the first case of a eukaryotic parasite-induced pseudotumorous syndrome in fish, which represents an emerging threat to conservation aquaculture and offering novel insights into parasite-mediated host metabolic hijacking and tumor-mimicry. Full article

Cell cultures are an essential tool for laboratory diagnosis of porcine viral infections. However, interpreting the results requires considering the species and tissue origin of cell lines as well as the specific virus replication characteristics (cytopathic effect). This guide discusses the development of techniques for the primary isolation of viruses from biological material and provides recommendations for culturing viruses in different cell types. According to the World Organization for Animal Health, laboratory diagnosis should aim to isolate the virus in cell culture. We have studied the evolution of virus isolation methods for various diseases affecting pigs, including African swine fever virus (ASFV), classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV), pseudorabies virus (Aujeszky’s disease, PRV), rotaviruses (RV), teschoviruses (PTVs), swine pox virus (SwPV), swine influenza A virus (IAVs), parvovirus (PPV), coronaviruses, circoviruses (PCVs), diseases with vesicular syndrome, and others. During our analysis of the literature and our own experience, we found that the porcine kidney (PK-15) cell line is the most suitable for isolating most viral porcine pathogens. For ASFV and PRRSV, the porcine alveolar macrophages (PAMs) continue to remain the primary model for isolation. These findings can serve as a starting point for virological reference laboratories to select optimal conditions for cultivating, obtaining field isolates, and strain adaptation. Full article

Oral infections caused by Candida spp. represent a major health concern due to the increasing resistance of these fungi to conventional antifungal agents. Photodynamic therapy (PDT) is a treatment based on the use of light at a specific wavelength that activates a photosensitizer (PS) in the presence of oxygen. The activated PS selectively binds to infected cells and induces apoptosis through the generation of reactive oxygen species (ROS). Previous biomolecular studies on Candida albicans have demonstrated that its infection triggers characteristic molecular signals, such as miRNA-146a and miRNA-155, which serve as inflammatory markers. This in vitro study aimed to evaluate the impact of PDT on the expression of their primary transcripts (pri-miRNAs) in a cell culture model of C. albicans infection. Human embryonic kidney (HEK-293) cells were infected with a multidrug-resistant strain of C. albicans (CA97) and subsequently exposed to curcumin-based PDT activated by blue light (470 nm). The expression of pri-miRNAs 146a and 155 was assessed before and after PDT treatment for each experimental group. The expression levels of pri-miRNAs increased approximately 2- to 3.5-fold following C. albicans infection but returned to baseline values after PDT treatment. The evaluation of pri-miRNAs 146a/155 may serve as a valuable research tool for monitoring early inflammatory responses induced by Candida infection, as well as a sensitive biomarker for assessing the effectiveness of photodynamic therapy in an in vitro cell culture model. Full article

Cellular communication network factor 2 (CCN2, also known as CTGF) is a complex protein that regulates numerous cellular functions. This biomolecule exhibits dual functions, depending on the context, and can act as a matricellular protein or as a growth factor. CCN2 is an established marker of fibrosis and a well-known mediator of kidney damage, involved in the regulation of inflammation, extracellular matrix remodeling, cell death, and activation of tubular epithelial cell (TECs) senescence. In response to kidney damage, cellular senescence mechanisms are activated, linked to regeneration failure and progression to fibrosis. Our preclinical studies using a total conditional CCN2 knockout mouse demonstrate that CCN2 plays a significant role in the development of a senescence phenotype after exposure to a nephrotoxic agent. CCN2 induces cell growth arrest in TECs, both in the early phase and in the chronic phase of folic acid nephropathy (FAN), associated with cell-death/necroinflammation and fibrosis, respectively. Renal CCN2 overexpression was found to be linked to excessive collagen accumulation in tubulointerstitial areas, microvascular rarefaction, and a decline in renal function, which were observed three weeks following the initial injury. All these findings were markedly diminished in conditional CCN2 knockout mice. In the FAN model, injured senescent TECs are associated with microvascular rarefaction, and both were modulated by CCN2. In primary cultured endothelial cells, as previously described in TECs, CCN2 directly induced senescence. The findings collectively demonstrate the complexity of CCN2, highlight the pivotal role of cellular senescence as an important mechanism in renal injury, and underscore the critical function of this biomolecule in kidney damage progression. Full article

Aquaculture is currently the fastest-growing sector in animal production, with an average annual growth rate of 7.5% since 1970. In Chile, the industry is largely driven by salmonid farming, with Salmo salar (Atlantic salmon) accounting for over 65% of national production. This species has shown the most significant growth within the sector. This growth is achieved by having high-density farming, which results in high levels of stress due to overcrowding and the appearance of pathogens such as the Infectious Salmon Anemia (ISA) virus, Bacterial Kidney Disease (BKD), Caligus sea lice (Caligus rogercresseyi), and Piscirickettsiosis (SRS) caused by Piscirickettsia salmonis, among others. This study evaluated the toxicity of the two most commonly used antibiotics in the salmon industry—oxytetracycline and florfenicol—at four concentrations each, using primary liver cell cultures of Atlantic salmon (Salmo salar). Oxidative stress was assessed through enzymatic activity and gene expression of oxidative markers, including cytochrome P450, catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR), and glutathione peroxidase (GPx). Samples were analyzed at 1, 3, 6, 12, and 48 h post-exposure. These findings reveal time- and dose-dependent oxidative responses in salmon liver cells to OTC and FLO, providing critical insights into the sublethal cellular effects of antibiotics commonly used in aquaculture, which indicates the presence of a high amount of free radicals in the liver cells, indicating toxicity of both antibiotics. Full article

A precision genome edit in the bovine CD46 gene (A₈₂LPTFS₈₇) dramatically reduced bovine viral diarrhea virus (BVDV) susceptibility in a cloned heifer. However, pathogen evolution threatens the long-term efficacy of such interventions. Here, our aim is two-fold: first, to determine whether BVDV can adapt in vitro to use the edited CD46 receptor to infect Madin–Darby bovine kidney (MDBK) cells, and second, to evaluate the ex vivo infectivity of culture-adapted viruses in cells from the CD46-edited heifer. Serial passage of BVDV on CD46-edited MDBK cells selected for virus variants capable of CD46-independent infection. Virus genome sequencing revealed mutations in the viral E^RNS gene predicted to enhance HS-mediated entry. HS adaptation was confirmed by inhibiting virus infection with heparin or Heparinase I/III treatment. A naturally occurring HS-adapted field isolate from a persistently infected calf showed similar results. However, when tested on primary cells from the CD46-edited heifer, HS-adapted viruses showed reduced infectivity in skin fibroblasts, monocytes, and lymphocytes in a manner that correlated with HS expression. Thus, although BVDV can adapt to use HS as an alternative entry receptor, HS adaptation does not overcome the protection conferred by the CD46 edit in all relevant cell types. Full article

Gut-derived uremic toxins (UTs) contribute to cardiovascular disorders like atherosclerosis and cardiomyopathy in patients with chronic kidney disease (CKD), causing increased cardiovascular morbidity and mortality. The intermediate steps between higher concentrations of gut-derived UTs and organ damage caused by UTs are still insufficiently understood. Glycosaminoglycans (GAGs) as components of the extracellular matrix are known to interact with various ligands such as growth factors or receptors, thereby influencing (patho)physiological processes. We previously found that the UT inorganic phosphate (Pi) induces the synthesis and sulphation of the GAGs heparan sulphate and chondroitin sulphate in the rat vascular smooth muscle cell (VSMC) line A7r5 and in the human endothelial cell (EC) line EA.Hy926. The aim of this study was to investigate if other organic UTs modulate GAGs in vascular cells as well. We treated ex vivo cultures of rat aortic rings as well as primary rat VSMCs and human ECs with the UTs Pi, indoxylsulphate (IS), p-cresylsulphate (pCS), trimethylamine N-oxide (TMAO), and urea, and analyzed the samples by histological staining, qPCR, western blot, HPLC, and colorimetric assays. The UT treatment of aortic rings and cells increased contents of sulphated GAGs and hyaluronic acid. UT-treated cells contained higher amounts of 4S- and 6S-sulphated GAGs compared to controls. This was accompanied by altered expressions of genes and proteins relevant for GAG metabolism. Mechanistically, the effects of the UTs on GAGs involve the activation of the PI3K/Akt pathway and of the transcription factor NF-κB. In conclusion, the UT-induced remodeling of the cardiovascular matrix by upregulation of sulphated GAGs and hyaluronic acid in aortic tissue and vascular cells might be a missing link between gut-derived UT and pathophysiological alterations in the cardiovascular system in the sense of a gut–matrix axis. Full article

Advanced glycation end-products (AGEs) cause blood vessel damage and induce diabetic complications in various organs, such as the eyes, kidneys, nerves, and skin. As glycation stress causes aesthetic, physical, and functional changes in the skin, glycation-targeting skin anti-aging strategies are attracting attention in cosmetology and dermatology. The primary goal of this review is to understand the significance of glycation-induced skin aging and to examine the therapeutic potential of glycation-targeting strategies. This study covers experimental and clinical studies exploring various interventions to attenuate glycation-induced skin aging. Glycation stress decreases the viability of cells in culture media, the cell-mediated contraction of collagen lattices in reconstructed skin models, and the expression of fibrillin-1 at the dermo-epidermal junction in the skin explants. It also increases cross-links in tail tendon collagen in animals, prolonging its breakdown time. However, these changes are attenuated by several synthetic and natural agents. Animal and clinical studies have shown that dietary or topical administration of agents with antiglycation or antioxidant activity can attenuate changes in AGE levels (measured by skin autofluorescence) and skin aging parameters (e.g., skin color, wrinkles, elasticity, hydration, dermal density) induced by chronological aging, diabetes, high-carbohydrate diets, ultraviolet radiation, or oxidative stress. Therefore, the accumulating experimental and clinical evidence supports that dietary supplements or topical formulations containing one or more synthetic and natural antiglycation agents may help mitigate skin aging induced by AGEs. Full article

The kidneys are integral to homeostasis but are susceptible to nephrotoxic compounds. Proximal tubular epithelial cells (PTECs) mediate drug metabolism and transport and are widely used in preclinical studies. However, commercial PTECs are limited in availability and physiological relevance. This study aimed to develop a novel, reliable protocol for isolating and culturing PTECs from human kidney biopsies. Primary PTECs were isolated from kidney biopsies of two patients (MFUM-RPTEC-1 and MFUM-RPTEC-2). Their morphology, population doubling time, transepithelial electrical resistance (TEER), and phenotypic markers were evaluated. Polarization and transporter expression were analyzed using cells cultured on Transwell inserts. Colonies formed within 24–48 h, with confluence reached by 8–10 days and dome (hemicyst) formation by day 13. TEER values peaked at 190 Ω/cm² after 7–14 days, confirming tight junction formation. Immunostaining identified characteristic markers (e.g., SGLT2, OAT1/3, OCT2, P-gp, MRP4, MATE1, N-cadherin, ZO-1, CK-18). Cells cultured on Transwell plates exhibited native polarization, expressing transporters crucial for drug excretion on apical and basolateral surfaces. We present two robust protocols for isolating and characterizing PTECs, offering a scalable method to obtain functional, polarized cells from scarce biopsy material. The isolated PTECs, therefore, present a valuable platform for preclinical studies, especially for drug excretion testing through the expressed transporters. Drug competition for these transporters during tubular secretion is also a common cause of nephrotoxicity. Full article