Search Results (1,109)

Osteoarthritis is a chronic inflammatory condition characterized by the degeneration of joint cartilage and underlying bone, resulting in pain, swelling, and reduced mobility. This study evaluates the efficacy of salmon nasal cartilage-derived proteoglycans in mitigating osteoarthritis symptoms and investigates the underlying molecular mechanisms. This study employed a rat model of osteoarthritis induced by monosodium iodoacetate (MIA) injection. The rats were orally administered salmon nasal cartilage-derived proteoglycans or ibuprofen. Key aspects of osteoarthritis pathology, including impaired exercise ability, inflammation, extracellular matrix degradation, and chondrocyte apoptosis, were assessed using histological analysis, micro-CT, treadmill testing, serum assays, and mRNA/protein expression studies. The MIA injection caused significant cartilage damage, reduced bone mineral density, and impaired exercise ability. Additionally, it elevated serum levels of prostaglandin E2 and nitric oxide, increased the mRNA and protein levels of inflammation-related factors, and activated apoptosis signaling pathways in cartilage. Treatment with salmon nasal cartilage-derived proteoglycans significantly improved cartilage morphology and mineralization, reduced inflammation, and inhibited apoptosis signaling pathways, with effects comparable to those observed with ibuprofen treatment. These findings highlight the potential of salmon nasal cartilage-derived proteoglycans as a therapeutic agent for managing osteoarthritis by effectively reducing inflammation, preventing cartilage degradation, and inhibiting chondrocyte apoptosis. Full article

Ferroptosis, a recently elucidated style of regulated cell death, has emerged as a significant area of investigation in cancer biology. Natural active compounds that have anti-cancer effects are promising candidates for cancer prevention. Iberverin, a natural compound derived from Brassica oleracea var. capitata, has been shown to exert anti-tumor activities in some cancers. However, its role in hepatocellular carcinoma (HCC) cells and the molecular mechanisms are still poorly understood. In this study, we proved that iberverin can induce intracellular reactive oxygen species (ROS) generation to inhibit cell proliferation and initiate ferroptotic cell death in HCC cells, which can be eradicated by the ferroptosis inhibitor ferrostatin-1 (Fer-1) or deferoxamine mesylate (DFO) and ROS scavenger (GSH or NAC). Mechanistically, iberverin treatment can simultaneously downregulate SLC7A11 mRNA level and degrade GPX4 through the ubiquitination pathway, leading to lipid peroxidation and ferroptotic cell death in HCC cells. Significantly, a low dose of iberverin can remarkably increase the sensitivity of HCC cells to ferroptosis induced by canonical ferroptosis inducers RSL3 and imidazole ketone erastin (IKE). This study uncovers a critical function of iberverin in preventing HCC through ferroptosis and provides a promising strategy for HCC treatment either via iberverin alone or in combination with canonical ferroptosis inducers in the future. Full article

Streptococcus pyogenes, or Group A Streptococcus (GAS), is responsible for over 500,000 deaths per year. Approximately 15% of these deaths are caused by necrotizing soft-tissue infections. In 2008, we isolated an M5 GAS, named the LO1 strain, responsible for the nosocomial transmission of necrotizing fasciitis between a baby and a nurse in Belgium. To understand this unusual transmission route, the LO1 strain was sequenced. A comparison of the LO1 genome and transcriptome with the reference M5 Manfredo strain was conducted. We found that the major differences were the presence of an additional DNase and a Tn916-like transposon in the LO1 and other invasive M5 genomes. RNA-seq analysis showed that genes present on the transposon were barely expressed. In contrast, the DNases presented different expression profiles depending on the tested conditions. We generated knock-out mutants in the LO1 background and characterized their virulence phenotype. We also determined their nuclease activity on different substrates. We found that DNases are dispensable for biofilm formation and adhesion to both keratinocytes and pharyngeal cells. Three of these were found to be essential for blood survival; Spd4 and Sdn are implicated in phagocytosis resistance, and Spd1 is responsible for neutrophil extracellular trap (NET) degradation. Full article

Lycii Radicis Cortex (LRC), the dried root bark of Lycium chinese Mill., has traditionally been used as a medicinal herb in East Asia to treat fever and hyperhidrosis. In the present study, we investigated the effects of LRC extract on ligation-induced experimental periodontitis and associated alveolar bone loss in rats. Twenty-four hours after ligation placement, LRC was orally administered once daily for 10 days. Firstly, LRC administration inhibited anaerobic bacterial proliferation and inflammatory cell infiltration in gingival tissues. Additionally, LRC exhibited anti-inflammatory effects by reducing the expression of inflammatory mediators, including prostaglandin E₂, interleukin-1β, and tumor necrosis factor-α. LRC treatment also downregulated mRNA expression of these inflammatory mediators in lipopolysaccharide-stimulated RAW 264.7 cells by inhibiting the mitogen-activated protein kinases and nuclear factor-κB (NF-κB) signaling pathways. Furthermore, LRC showed an antioxidant effect by decreasing the malondialdehyde level and inducible nitric oxide synthase activity in gingival tissues. Moreover, LRC effectively prevented the connective tissue degradation by inhibiting matrix metalloproteinase-8 expression and the loss of collagen-occupied areas in gingival tissues. LRC also decreased the receptor activator of NF-κB ligand/osteoprotegerin (RANKL/OPG) ratio, as well as the number and occupied areas of osteoclasts on the alveolar bone surface, thereby inhibiting alveolar bone loss. In summary, these findings suggest that LRC is a promising medicinal herb for alleviating periodontitis and related alveolar bone loss through its antimicrobial, anti-inflammatory, and antioxidant properties. Full article

MicroRNAs (miRNAs) are small, endogenous, single-stranded RNAs that act on gene silencing at the post-transcriptional level by binding to a target messenger RNA (mRNA), leading to its degradation or inhibiting translation into functional proteins. The key role of miRNAs in development, proliferation, differentiation andapoptosis has been deeply investigated, revealing that deregulation in their expression is critical in various diseases, such as metabolic disorders and cancer. Since these small molecules initially evolved as a mechanism of protection against viruses and transposable elements, the fascinating hypothesis that they can move between organisms both of the same or different species has been postulated. Trans-kingdom is the term used to define the migration that occurs between species. This mechanism has been well analyzed between plants and their pests, in order to boost defense and increase pathogenicity, respectively. Intriguingly, in the last decades, the plant–human trans-kingdom migration via food intake hypothesis arose. In particular, various studies highlighted the ability of exogenous miRNAs, abundant in the mainly consumed plant-derived food, to enter the human body affecting gene expression. Notably, plant miRNAs can resist the strict conditions of the gastrointestinal tract through a methylation step that occurs during miRNA maturation, conferring high stability to these small molecules. Recent studies observed the anti-tumoral, immune modulator and anti-inflammatory abilities of trans-kingdom interaction between plant and human. Here, we depict the existing knowledge and discuss the fascinating plant–human trans-kingdom interaction, highlighting first the eventual role of plant miRNAs from foods on our somatic gene identity card and then the potential impact of using plant miRNAs as novel therapeutic avenues. Full article

Branched-chain amino acids (BCAAs) are essential for muscle protein synthesis and are widely acknowledged for mitigating sarcopenia. Oligonol^® (Olg), a low-molecular-weight polyphenol from Litchi chinensis, has also been found to attenuate sarcopenia by improving mitochondrial quality and positive protein turnover. This study aims to investigate the effect of Olg on BCAA-stimulated protein synthesis in sarcopenia. In sarcopenic C57BL/6 mice and senescence-accelerated mouse-prone 8 (SAMP8) mice, BCAAs were significantly decreased in skeletal muscle but increased in blood serum. Furthermore, the expressions of membrane L-type amino acid transporter 1 (LAT1) and branched-chain amino acid transaminase 2 (BCAT2) in skeletal muscle were lower in aged mice than in young mice. The administration of Olg for 8 weeks significantly increased the expressions of membrane LAT1 and BCAT2 in the skeletal muscle when compared with non-treated SAMP8 mice. We further found that BCAA deprivation via LAT1-siRNA in C2C12 myotubes inhibited the signaling of protein synthesis and facilitated ubiquitination degradation of BCAT2. In C2C12 cells mimicking sarcopenia, Olg combined with BCAA supplementation enhanced mTOR/p70S6K activity more than BCAA alone. However, blocked LAT1 by JPH203 reversed the synergistic effect of the combination of Olg and BCAAs. Taken together, changes in LAT1 and BCAT2 during aging profoundly alter BCAA availability and nutrient signaling in aged mice. Olg increases BCAA-stimulated protein synthesis via modulating BCAA transportation and BCAA catabolism. Combining Olg and BCAAs may be a useful nutritional strategy for alleviating sarcopenia. Full article

N6-methyladenosine (m⁶A) is the most common modification in eukaryotic RNAs. Growing research indicates that m⁶A methylation is crucial for a multitude of biological processes. However, research on the m⁶A modifications in the regulation of porcine muscle growth is lacking. In this study, we identified differentially expressed genes in the neonatal period of muscle development between Large White (LW) and NingXiang (NX) pigs and further reported m⁶A methylation patterns via MeRIP-seq. We found that m⁶A modification regulates muscle cell development, myofibrils, cell cycle, and phosphatase regulator activity during the neonatal phase of muscle development. Interestingly, differentially expressed genes in LW and NX pigs were mainly enriched in pathways involved in protein synthesis. Furthermore, we performed a conjoint analysis of MeRIP-seq and RNA-seq data and identified 27 differentially expressed and m⁶A-modified genes. Notably, a typical muscle-specific envelope transmembrane protein, WFS1, was differentially regulated by m⁶A modifications in LW and NX pigs. We further revealed that the m⁶A modification accelerated the degradation of WFS1 in a YTHDF2-dependent manner. Noteworthy, we identified a single nucleotide polymorphism (C21551T) within the last exon of WFS1 that resulted in variable m⁶A methylation, contributing to the differing WFS1 expression levels observed in LW and NX pigs. Our study conducted a comprehensive analysis of the m⁶A modification on NX and LW pigs during the neonatal period of muscle development, and elucidated the mechanism by which m⁶A regulates the differential expression of WFS1 in the two breeds. Full article

Deleterious variations in STXBP1 are responsible for early infantile epileptic encephalopathy type 4 (EIEE4, OMIM # 612164) because of its dysfunction in the central nervous system. The clinical spectrum of the neurodevelopmental delays associated with STXBP1 aberrations is collectively defined as STXBP1 encephalopathy (STXBP1-E), the conspicuous features of which are highlighted by early-onset epileptic seizures without structural brain anomalies. A girl was first diagnosed with unexplained disorders of movement and cognition, which later developed into STXBP1-E with unexpected leukoaraiosis and late onset of seizures. Genetic screening and molecular tests alongside neurological examinations were employed to investigate the genetic etiology and establish the diagnosis. A heterozygous mutation of c.37+2dupT at the STXBP1 splice site was identified as the pathogenic cause in the affected girl. The de novo mutation (DNM) did not result in any truncated proteins but immediately triggered mRNA degradation by nonsense-mediated mRNA decay (NMD), which led to the haploinsufficiency of STXBP1. The patient showed atypical phenotypes characterized by hypomyelinating leukodystrophy, and late onset of epileptic seizures, which had never previously been delineated in STXBP1-E. These findings strongly indicated that the haploinsufficiency of STXBP1 could also exhibit divergent clinical phenotypes because of the genetic heterogeneity in the subset of encephalopathies. Full article

MicroRNAs (miRNAs) are small, non-coding RNAs that control gene expression by degrading or repressing mRNA translation into proteins. Research recently suggested that food-derived miRNAs are bioavailable and may be absorbed in the gastrointestinal tract (GIT). Since these small RNAs may reach the circulation and organs, possible interactions with host genes will lead to epigenetic effects that alter metabolism. Therefore, from a precision nutrition standpoint, exogenous miRNAs may be essential in modulating health status. This review summarizes the process of miRNA biogenesis, the post-translational mechanisms of gene regulation, and their bioavailability in animal- and plant-derived foods. Full article

Eukaryotic cells possess surveillance mechanisms that detect and degrade defective transcripts. Aberrant transcripts include mRNAs with a premature termination codon (PTC), targeted by the nonsense-mediated decay (NMD) pathway, and mRNAs lacking a termination codon, targeted by the nonstop decay (NSD) pathway. The eukaryotic exosome, a ribonucleolytic complex, plays a crucial role in mRNA processing and turnover through its catalytic subunits PM/Scl100 (Rrp6 in yeast), DIS3 (Rrp44 in yeast), and DIS3L1. Additionally, eukaryotic cells have other ribonucleases, such as SMG6 and XRN1, that participate in RNA surveillance. However, the specific pathways through which ribonucleases recognize and degrade mRNAs remain elusive. In this study, we characterized the involvement of human ribonucleases, both nuclear and cytoplasmic, in the mRNA surveillance mechanisms of NMD and NSD. We performed knockdowns of SMG6, PM/Scl100, XRN1, DIS3, and DIS3L1, analyzing the resulting changes in mRNA levels of selected natural NMD targets by RT-qPCR. Additionally, we examined the levels of different human β-globin variants under the same conditions: wild-type, NMD-resistant, NMD-sensitive, and NSD-sensitive. Our results demonstrate that all the studied ribonucleases are involved in the decay of certain endogenous NMD targets. Furthermore, we observed that the ribonucleases SMG6 and DIS3 contribute to the degradation of all β-globin variants, with an exception for βNS in the former case. This is also the case for PM/Scl100, which affects all β-globin variants except the NMD-sensitive variants. In contrast, DIS3L1 and XRN1 show specificity for β-globin WT and NMD-resistant variants. These findings suggest that eukaryotic ribonucleases are target-specific rather than pathway-specific. In addition, our data suggest that ribonucleases play broader roles in mRNA surveillance and degradation mechanisms beyond just NMD and NSD. Full article

Background: Pancreatic ductal adenocarcinoma (PDAC) is among the most aggressive forms of pancreatic cancer with a poor prognosis. YAP1 expression is markedly elevated in PDAC, but how it works is not clear. GL-V9, a derivative of the natural compound wogonin, effectively fights a variety of tumors; however, its effect on PDAC has not yet been studied. Methods: TCGA database analysis, Western blots, immunofluorescence, and real-time PCR were used to evaluate GL-V9’s effect on YAP1 expression and mRNA levels. Immunofluorescence was used to examine the co-location of YAP1 with LAMP2 and p62. Co-immunoprecipitation was used to assess the binding of YAP1 to ubiquitin, p62, and TEAD1. A PDAC graft tumor model was used to test GL-V9’s pharmacological effects. Western blots and immunohistochemistry were used to measure apoptosis- and autophagy-related protein expression. Results: GL-V9 effectively promoted the degradation of YAP1, reduced YAP1 nuclear localization, and induced mitochondrial apoptosis in PDAC cells. YAP1 overexpression led to the upregulation of Bcl-2 and attenuated the caspase cascade induced by GL-V9. Furthermore, we demonstrated that GL-V9 induced autophagosome–lysosome fusion via the AKT/mTOR/TFEB pathway, leading to mitochondrial apoptosis in PDAC cells. In vivo studies also confirmed that GL-V9 exerts anti-tumor effects by suppressing YAP1 expression, while also activating autophagy and inducing mitochondrial apoptosis in BXPC-3-bearing BALB/c nude mice. Conclusions: Our findings underscore the importance of autophagy-mediated YAP1 degradation in PDAC, providing a novel molecular rationale (GL-V9) as a promising treatment for this disease. Full article

Lateolabrax maculatus iridovirus (LMIV) is a variant strain of red sea bream iridovirus (RSIV), causing serious economic losses in aquaculture. Claudins (CLDNs) are major components of tight junctions (TJs) forming an important line of defense against pathogens. Our pilot miRNA-mRNA joint analysis indicated the degradation of CLDN3, as well as its interaction with miR-181a during LMIV infection. To elucidate the miR-181a/CLDN3/LMIV interactions, in vitro assays were carried out on LMB-L cells. We first confirmed that LMIV infection could decrease the expression of CLDN3, accompanied by the enhancement of permeability, suggesting the dysfunction of TJs. Contrary to the inhibition of CLDN3, the activation of miR-181a was proved, presenting a negative correlation between miR-181a and CLDN3 (Pearson r = −0.773 and p < 0.01). In addition, the influence of CLDN3 on LMIV replication was analyzed by knockdown and over-expression of CLDN3. When CLDN3 was silenced in LMB-L cells with siCLDN3-623 at 9 days post transfection (dpt), LMIV copies and titers were significantly up-regulated by 1.59-fold and 13.87-fold, respectively. By contrast, LMIV replication in LMB-L cells was reduced by 60% and 71%, post transfection with pcDNA3.1-CLDN3 over-expressed plasmid at 6 dpt and 9 dpt, respectively. Ultimately, the regulatory relationship between miR-181a and CLDN3 was further validated by dual luciferase reporter assays. Taking into account the above-described results, we proposed a “miR-181a/CLDN3/LMIV” regulatory relationship. This study provides a new insight for understanding the mechanism of LMIV replication. Full article

Introduction: The advent of lipid nanoparticles (LNPs) as a delivery platform for mRNA therapeutics has revolutionized the biomedical field, particularly in treating infectious diseases, cancer, genetic disorders, and metabolic diseases. Recent Advances in Therapeutic LNPs: LNPs, composed of ionizable lipids, phospholipids, cholesterol, and polyethylene glycol (PEG) lipids, facilitate efficient cellular uptake and cytosolic release of mRNA while mitigating degradation by nucleases. However, as synthetic entities, LNPs face challenges that alter their therapeutic efficacy and safety concerns. Toxicity/Reactogenicity/Immunogenicity: This review provides a comprehensive overview of the latest advancements in LNP research, focusing on preclinical safety assessments encompassing toxicity, reactogenicity, and immunogenicity. Summary and Outlook: Additionally, it outlines potential strategies for addressing these challenges and offers insights into future research directions for enhancing the application of LNPs in mRNA therapeutics. Full article

Autophagy is essential for cell survival and cellular homeostasis under various stress conditions. Therefore, autophagy dysfunction is associated with the pathogenesis of various human diseases. We explored the regulatory role of RhoBTB3 in autophagy and its interaction with activating molecules in AMBRA1. RhoBTB3 deficiency was found to induce autophagy, while its overexpression inhibited autophagy induction. Through immunoprecipitation and mass spectrometry, AMBRA1 was identified as a substrate of RhoBTB3. The study revealed that RhoBTB3 regulates AMBRA1 stability by influencing its protein levels without affecting its mRNA levels. RhoBTB3 induced the ubiquitination of AMBRA1, leading to proteasome-mediated degradation, with the ubiquitination occurring at K45 on AMBRA1 through a K27-linked ubiquitin chain. The knockdown of AMBRA1 blocked RhoBTB3 knockdown-induced autophagy, indicating the dependency of autophagy on AMBRA1. Thus, RhoBTB3 negatively regulates autophagy by mediating AMBRA1 ubiquitination and degradation, suggesting RhoBTB3 as a potential therapeutic target for autophagy-related diseases. Full article

The E3 ubiquitin ligase Smurf1 catalyzes the ubiquitination and proteasomal degradation of several protein substrates related to inflammatory responses and antiviral signaling. This study investigated the role of Smurf1 in modulating inflammation induced by Betacoronavirus infection. Bone marrow-derived macrophages (BMDMs) from C57BL/6 (wild-type) or Smurf1-deficient (Smurf1^−/−) mice were infected with MHV-A59 to evaluate the inflammatory response in vitro. Smurf1 was found to be required to downregulate the macrophage production of pro-inflammatory mediators, including TNF, and CXCL1; to control viral release from infected cells; and to increase cell viability. To assess the impact of Smurf 1 in vivo, we evaluated the infection of mice with MHV-A59 through the intranasal route. Smurf1^−/− mice infected with a lethal inoculum of MHV-A59 succumbed earlier to infection. Intranasal inoculation with a 10-fold lower dose of MHV-A59 resulted in hematological parameter alterations in Smurf1^−/− mice suggestive of exacerbated systemic inflammation. In the lung parenchyma, Smurf1 expression was essential to promote viral clearance, downregulating IFN-β mRNA and controlling the inflammatory profile of macrophages and neutrophils. Conversely, Smurf1 did not affect IFN-β mRNA regulation in the liver, but it was required to increase TNF and iNOS expression in neutrophils and decrease TNF expression in macrophages. In addition, Smurf1^−/− mice exhibited augmented liver injuries, accompanied by high serum levels of alanine aminotransferase (ALT). These findings suggest that Smurf1 plays a critical role in regulating the inflammatory response in macrophages and attenuating systemic inflammation during Betacoronavirus infection. Full article