Kelsey M. Wheeler, Myung Whan Oh, Julianna Fusco
et al.
Infections often occur in complex niches consisting of multiple bacteria. Despite the increasing awareness, there is a fundamental gap in understanding which interactions govern microbial community composition. <i>Pseudomonas aeruginosa</i> is frequently isolated from monomicrobial and polymicrobial human infections. This pathogen forms polymicrobial infections with other ESKAPEE pathogens and defies eradication by conventional therapies. By analyzing the competition within co-cultures of <i>P. aeruginosa</i> and representative secondary pathogens that commonly co-infect patients, we demonstrate the antagonism of <i>P. aeruginosa</i> against other ESKAPEE pathogens and the contribution of this pathogen’s multiple quorum-sensing (QS) systems in these interactions. QS is a highly conserved bacterial cell-to-cell communication mechanism that coordinates collective gene expressions at the population level, and it is also involved in <i>P. aeruginosa</i> virulence. Using a collection of <i>P. aeruginosa</i> QS mutants of the three major systems, LasR/LasI, MvfR/PqsABCDE, and RhlR/RhlI, and mutants of several QS-regulated functions, we reveal that MvfR and, to a lesser extent, LasR and RhlR, control competition between <i>P. aeruginosa</i> and other microbes, possibly through their positive impact on pyoverdine, pyochelin, and phenazine genes. We show that MvfR inhibition alters competitive interspecies interactions and preserves the coexistence of <i>P. aeruginosa</i> with the ESKAPEE pathogens tested while disarming the pathogens’ ability to form biofilm and adhere to lung epithelial cells. Our results highlight the role of MvfR inhibition in modulating microbial competitive interactions across multiple species, while simultaneously attenuating virulence traits. These findings reveal the complexity and importance of QS in interspecies interactions and underscore the impact of the anti-virulence approach in microbial ecology and its importance for treating polymicrobial infections.
Iwona Lasocka, Michał Skibniewski, Iwona Pasternak
et al.
Graphene-based materials (GBMs), owing to their excellent biomedical properties, can significantly advance the development of nano-biodressings. Their unique physicochemical features, such as high surface area, tunable functionalization, antimicrobial activity, and ability to interact with immune cells, suggest that GBMs may influence key biological processes involved in tissue repair, particularly the immune response. Building on this growing evidence, the aim of this review is to demonstrate that GBMs can serve as tools for modulating macrophage polarization as a strategy for promoting wound healing. We present the mechanisms by which GBMs penetrate macrophages and discuss the effects of GBMs, either in suspension or as scaffolds/grounds/substrates, on macrophage polarization. Moreover, we propose mechanisms underlying the actions of different forms of GBMs on macrophage polarization. Nevertheless, a multitude of uncertainties and significant challenges remain. Chief among these are the pronounced heterogeneity of GBM subtypes, the necessity for exhaustive characterization and in-depth analysis, the formulation of robust experimental designs, and the careful selection of models capable of accurately delineating macrophage populations and guiding their polarization toward achieving targeted wound healing outcomes. This review attempts to systematize and clarify these issues.
Abstract Excessive scar formation such as hypertrophic scars and keloids, resulting from trauma or surgical procedures, present a widespread concern for causing disfigurement, discomfort, and functional limitations. Macrophages play pivotal roles in maintaining tissue homeostasis, orchestrating tissue development, repair, and immune responses, and its transition of function and phenotype plays a critical role in regulating the balance between inflammation and tissue regeneration, which is central to cutaneous scar formation. Recent evidence suggests the involvement of Sonic Hedgehog (SHH) in the induction of anti-inflammatory M2-like macrophage phenotypes within tumor microenvironments. In our study, we observed increased SHH expression in human hypertrophic scars, prompting an investigation into its influence on macrophage polarization, efferocytosis, and cutaneous scar formation. Our findings reveal that SHH can enhance oxidative phosphorylation (OXPHOS) in macrophages, augment macrophage efferocytosis, and promote M2 polarization, finally contributing to the progression of cutaneous scar formation. Notably, targeting SHH signaling with vismodegib exhibited promising potential in mitigating scar formation by reversing the effects of enhanced OXPHOS and M2 polarization in macrophages. In conclusion, this study underscores the critical roles of macrophage metabolism, particularly OXPHOS, efferocytosis and SHH signaling in cutaneous scar formation. Understanding these mechanisms provides new avenues for potential interventions and scar prevention strategies.
Faride Nam Avar Jahromi, Razieh Dowran, Reza Jafari
Abstract In clinical diagnosis, the capability of exosomes to serve as biomarkers is one of the most important biological functions of exosomes. The superior stability of exosome biomarkers makes them superior to those isolated from traditional samples such as serum and urine. Almost all body fluids contain exosomes, which contain proteins, nucleic acids, and lipids. Several molecular components of exosomes, including exosome proteins and microRNAs (miRNAs), are promising diagnostic biomarkers. These exosomes may carry genetic information by containing messenger RNA (mRNA) and miRNA. The miRNAs are small noncoding RNAs that regulate protein-coding genes by acting as translational repressors. It has been shown that miRNAs are mis-expressed in a range of conditions, including hematologic neoplasms. Additionally, miRNAs found within exosomes have been linked with specific diseases, including hematologic neoplasms. Numerous studies suggest that circulating exosomes contain miRNAs similar to those found in parental cancer cells. Exosomes contain miRNAs that are released by almost all kinds of cells. MiRNAs are packaged into exosomes and delivered to recipient cells, and manipulate its function. It has been recognized that exosomes are new therapeutic targets for immunotherapy and biomedicine of cancers. The current review discusses the current evidence around exosomal miRNAs involved in the pathogenesis, diagnosis, and treatment of hematologic neoplasms. Video Abstract
Seiji Nakahara, Shunsuke Doi, Satoshi Nishiwada
et al.
Abstract Background Pancreatic lipomas (PLs) arising from the adipose tissue in the pancreatic parenchyma are rare among pancreatic tumors. Coexisting pancreatic ductal adenocarcinoma (PDAC) and PLs have not been previously reported. Herein, we report a case of PDAC arising from the pancreatic parenchyma with chronic pancreatitis compressed by a large PL. Case presentation The patient was a 69-year-old male. He had been diagnosed with a PL using computed tomography (CT) 12 years previously. The tumor had been slowly growing and was followed up carefully because of the possibility of well-differentiated liposarcoma. During follow-up, laboratory data revealed liver damage and slightly elevated levels of inflammatory markers. Contrast-enhanced CT revealed the previously diagnosed 12 cm pancreatic head tumor and an irregular isodensity mass at the upper margin of the tumor that invaded and obstructed the distal common bile duct. Magnetic resonance cholangiopancreatography demonstrated no specific findings in the main pancreatic duct. Based on these imaging findings, the patient underwent endoscopic retrograde biliary drainage and bile duct brushing cytology, which revealed indeterminate findings. The differential diagnosis of the tumor at that time was as follows: (1) pancreatic liposarcoma (focal change from well-differentiated to dedifferentiated, not lipoma), (2) distal cholangiocarcinoma, and (3) pancreatic cancer. After the cholangitis improved, a pancreatoduodenectomy was performed. Histologically, hematoxylin–eosin staining revealed moderately differentiated PDAC compressed by proliferating adipose tissue. The adipose lesion showed homogeneous adipose tissue with no evidence of sarcoma, which led to a diagnosis of lipoma. Additionally, extensive fibrosis of the pancreatic parenchyma and atrophy of the acinar cells around the lipoma was suggestive of chronic pancreatitis. The pathological diagnosis was PDAC (pT2N0M0 pStage Ib) with chronic pancreatitis and PL. The postoperative course was uneventful, and the patient was discharged on the 15th day after surgery. The patient received adjuvant chemotherapy and has remained recurrence-free for more than 6 months. Conclusions PL may be associated with the development of PDAC in the surrounding inflammatory microenvironment of chronic pancreatitis. In cases of growing lipomas, careful radiologic surveillance may be needed not only for the possibility of liposarcoma but also for the coincidental occurrence of PDAC.
Alla K. Ovsyannikova, Vlada I. Alferova, Oksana D. Rymar
Of all types of diabetes mellitus (DM), type 1 diabetes mellitus (DM1) and type 2 diabetes (DM2) are most often diagnosed in young people. However, up to 10 % of all cases of DM diagnosed at a young age are monogenic forms of DM – MODY (Maturity-Onset Diabetes of the Young), the most common forms of which are MODY2 (GCK-MODY) and MODY3 (HNF1AMODY). These genetic forms of DM are poorly understood, so the investigation of their clinical and biochemical parameters, including lipid profile, and comparison with more studied forms of DM is of high importance. The aim of this study was to analyze the characteristics of the lipid profile in patients aged 18–45 years with DM1, DM2, GCK-MODY and HNF1A-MODY.
Material and methods. In 56 patients diagnosed by the molecular genetic method MODY, as well as in 82 patients with DM2 and 14 patients with DM1, matched by sex, age, a lipid profile was studied.
Results. There were no statistically significant differences in total cholesterol and low-density lipoprotein cholesterol between young patients with different types of DM. In HNF1a-MODY, the highest level of triglycerides was revealed; in DM1, the level of high-density lipoprotein cholesterol was significantly higher than in other types of DM. Among the changes in the lipid profile among all types of DM, hypercholesterolemia was more often determined.
Diseases of the blood and blood-forming organs, Diseases of the circulatory (Cardiovascular) system
Mitochondria are not only the main energy supplier but are also the cell metabolic center regulating multiple key metaborates that play pivotal roles in epigenetics regulation. These metabolites include acetyl-CoA, α-ketoglutarate (α-KG), S-adenosyl methionine (SAM), NAD<sup>+</sup>, and O-linked beta-N-acetylglucosamine (O-GlcNAc), which are the main substrates for DNA methylation and histone post-translation modifications, essential for gene transcriptional regulation and cell fate determination. Tumorigenesis is attributed to many factors, including gene mutations and tumor microenvironment. Mitochondria and epigenetics play essential roles in tumor initiation, evolution, metastasis, and recurrence. Targeting mitochondrial metabolism and epigenetics are promising therapeutic strategies for tumor treatment. In this review, we summarize the roles of mitochondria in key metabolites required for epigenetics modification and in cell fate regulation and discuss the current strategy in cancer therapies via targeting epigenetic modifiers and related enzymes in metabolic regulation. This review is an important contribution to the understanding of the current metabolic-epigenetic-tumorigenesis concept.
Stevioside, the primary sweetener in stevia, is a glycoside with numerous beneficial biological activities. However, its anti-adipogenic effects on tissue differentiation and adipose tissues remain to be thoroughly investigated. In this study, the anti-adipogenic effects of stevioside during the differentiation of 3T3-L1 cells and epididymal adipose tissues of <i>db/db</i> mice were investigated by measuring the lipid droplets stained with Oil Red O and an immunoblot assay. Immunoblot analysis revealed that stevioside downregulated the expression of peroxisome proliferator-activated receptor-gamma (PPARγ), sterol regulatory element-binding protein-1c (SREBP-1c), CCAAT/enhancer-binding protein alpha (C/EBPα), and fatty acid synthase (FAS). Additionally, the protein expression of carnitine palmitoyltransferase 1 (CPT1), silent mating type information regulation 2 homolog 1 (SIRT1), and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) increased following treatment with stevioside. Furthermore, stevioside increased the phosphorylation of adenosine monophosphate (AMP)-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), both in vitro and in vivo. The activity of AMPK in stevioside-treated 3T3-L1 cells was further confirmed using agonists and antagonists of AMPK signaling. Our data indicate that stevioside ameliorates anti-adipogenic effects and promotes β-oxidation in adipocytes by activating AMPK-mediated signaling. The results of this study clearly demonstrated the inhibitory effect of stevioside on the differentiation of adipocytes and the reduction of lipid accumulation in the epididymal adipose tissues of <i>db/db</i> mice.
Foteini Vasilopoulou, Aina Bellver-Sanchis, Júlia Companys-Alemany
et al.
Behavioural and psychological symptoms of dementia (BPSD) are presented in 95% of Alzheimer’s Disease (AD) patients and are also associated with neurotrophin deficits. The molecular mechanisms leading to age-related diseases are still unclear; however, emerging evidence has suggested that epigenetic modulation is a key pathophysiological basis of ageing and neurodegeneration. In particular, it has been suggested that G9a methyltransferase and its repressive histone mark (H3K9me2) are important in shaping learning and memory by modulating autophagic activity and synaptic plasticity. This work deepens our understanding of the epigenetic mechanisms underlying the loss of cognitive function and BPSD in AD. For this purpose, several tasks were performed to evaluate the parameters of sociability (three-chamber test), aggressiveness (resident intruder), anxiety (elevated plus maze and open field) and memory (novel object recognition test) in mice, followed by the evaluation of epigenetic, autophagy and synaptic plasticity markers at the molecular level. The behavioural alterations presented by senescence-accelerated mice prone 8 (SAMP8) of 12 months of age compared with their senescence-accelerated mouse resistant mice (SAMR1), the healthy control strain was accompanied by age-related cognitive deficits and alterations in epigenetic markers. Increased levels of G9a are concomitant to the dysregulation of the JNK pathway in aged SAMP8, driving a failure in autophagosome formation. Furthermore, lower expression of the genes involved in the memory-consolidation process modulated by ERK was observed in the aged male SAMP8 model, suggesting the implication of G9a. In any case, two of the most important neurotrophins, namely <i>brain-derived neurotrophic factor (Bdnf)</i> and <i>neurotrophin-3 (NT3),</i> were found to be reduced, along with a decrease in the levels of dendritic branching and spine density presented by SAMP8 mice. Thus, the present study characterizes and provides information regarding the non-cognitive and cognitive states, as well as molecular alterations, in aged SAMP8, demonstrating the AD-like symptoms presented by this model. In any case, our results indicate that higher levels of G9a are associated with autophagic deficits and alterations in synaptic plasticity, which could further explain the BPSD and cognitive decline exhibited by the model.
Abstract In adult skeletal muscle, satellite cells are in a quiescent state, which is essential for the future activation of muscle homeostasis and regeneration. Multiple studies have investigated satellite cell proliferation and differentiation, but the molecular mechanisms that safeguard the quiescence of satellite cells remain largely unknown. In this study, we purposely activated dormant satellite cells by using various stimuli and captured the in vivo-preserved features from quiescence to activation transitions. We found that retinoic acid signaling was required for quiescence maintenance. Mechanistically, retinoic acid receptor gamma (RARγ) binds to and stimulates genes responsible for Akt dephosphorylation and subsequently inhibits overall protein translation initiation in satellite cells. Furthermore, the alleviation of retinoic acid signaling released the satellite cells from quiescence, but this restraint was lost in aged cells. Retinoic acid also preserves the quiescent state during satellite cell isolation, overcoming the cellular stress caused by the isolation process. We conclude that active retinoic acid signaling contributes to the maintenance of the quiescent state of satellite cells through regulation of the protein translation initiation process.
Leon J. Blankenstein, Nils Cordes, Leoni A. Kunz-Schughart
et al.
Glioblastoma is a devastating malignant disease with poor patient overall survival. Strong invasiveness and resistance to radiochemotherapy have challenged the identification of molecular targets that can finally improve treatment outcomes. This study evaluates the influence of all six known p21-activated kinase (PAK) protein family members on the invasion capacity and radio-response of glioblastoma cells by employing a siRNA-based screen. In a panel of human glioblastoma cell models, we identified PAK4 as the main PAK isoform regulating invasion and clonogenic survival upon irradiation and demonstrated the radiosensitizing potential of PAK4 inhibition. Mechanistically, we show that PAK4 depletion and pharmacological inhibition enhanced the number of irradiation-induced DNA double-strand breaks and reduced the expression levels of various DNA repair proteins. In conclusion, our data suggest PAK4 as a putative target for radiosensitization and impairing DNA repair in glioblastoma, deserving further scrutiny in extended combinatorial treatment testing.
Diana Ferraro, Sara De Biasi, Anna Maria Simone
et al.
The altered numbers and functions of cells belonging to immunoregulatory cell networks such as T regulatory (Tregs) and invariant Natural Killer T (iNKT) cells have been reported in Multiple Sclerosis (MS), an immune-mediated disease. We aimed to assess the frequencies of Tregs and iNKT cells in MS patients throughout a one-year treatment with fingolimod (FTY) and to correlate immunological data with efficacy and safety data. The percentage of Tregs (defined as Live Dead-CD3 + CD4 + FoxP3 + CD25++/CD127− cells) increased steadily throughout the year, while there was no significant difference in the absolute number or percentage of iNKT cells (defined as CD3 + CD14−CD19− Vα24-Jα18 TCR+ cells). However, out of all the iNKT cells, the CD8+ iNKT and CD4−CD8− double-negative (DN) cell percentages steadily increased, while the CD4+ iNKT cell percentages decreased significantly. The mean percentage of CD8+ T cells at all time-points was lower in patients with infections throughout the study. The numbers and percentages of DN iNKT cells were more elevated, considering all time-points, in patients who presented a clinical relapse. FTY may, therefore, exert its beneficial effect in MS patients through various mechanisms, including the increase in Tregs and in iNKT subsets with immunomodulatory potential such as CD8+ iNKT cells. The occurrence of infections was associated with lower mean CD8+ cell counts during treatment with FTY.
Stefan Teufel, Petra Köckemann, Christine Fabritius
et al.
Abstract Agonists and antagonists of the canonical Wnt signaling pathway are modulators of pathological aspects of rheumatoid arthritis (RA). Their activity is primarily modifying bone loss and bone formation, as shown in animal models of RA. More recently, modulation of Wnt signaling by the antagonist Sclerostin has also been shown to influence soft-tissue-associated inflammatory aspects of the disease pointing towards a role of Wnt signaling in soft-tissue inflammation as well. Yet, nothing is known experimentally about the role of Wnt ligands in RA. Here we provide evidence that altering Wnt signaling at the level of a ligand affects all aspects of the rheumatoid arthritic disease. WNT9a levels are increased in the pannus tissue of RA patients, and stimulation of synovial fibroblasts (SFB) with tumor necrosis factor (TNF) leads to increased transcription of Wnt9a. Loss of Wnt9a in a chronic TNF-dependent RA mouse model results in an aggravation of disease progression with enhanced pannus formation and joint destruction. Yet, loss of its activity in the acute K/BxN serum-transfer induced arthritis (STIA) mouse model, which is independent of TNF signaling, has no effect on disease severity or progression. Thus, suggesting a specific role for WNT9a in TNF-triggered RA. In synovial fibroblasts, WNT9a can activate the canonical Wnt/β-catenin pathway, but it can also activate P38- and downregulate NFκB signaling. Based on in vitro data, we propose that loss of Wnt9a creates a slight proinflammatory and procatabolic environment that boosts the TNF-mediated inflammatory response.
David Della-Morte, Francesca Pacifici, Camillo Ricordi
et al.
Abstract The pathophysiology of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and especially of its complications is still not fully understood. In fact, a very high number of patients with COVID-19 die because of thromboembolic causes. A role of plasminogen, as precursor of fibrinolysis, has been hypothesized. In this study, we aimed to investigate the association between plasminogen levels and COVID-19-related outcomes in a population of 55 infected Caucasian patients (mean age: 69.8 ± 14.3, 41.8% female). Low levels of plasminogen were significantly associated with inflammatory markers (CRP, PCT, and IL-6), markers of coagulation (D-dimer, INR, and APTT), and markers of organ dysfunctions (high fasting blood glucose and decrease in the glomerular filtration rate). A multidimensional analysis model, including the correlation of the expression of coagulation with inflammatory parameters, indicated that plasminogen tended to cluster together with IL-6, hence suggesting a common pathway of activation during disease’s complication. Moreover, low levels of plasminogen strongly correlated with mortality in COVID-19 patients even after multiple adjustments for presence of confounding. These data suggest that plasminogen may play a pivotal role in controlling the complex mechanisms beyond the COVID-19 complications, and may be useful both as biomarker for prognosis and for therapeutic target against this extremely aggressive infection.
Yiyao Huang, Lesley Cheng, Andrey Turchinovich
et al.
Extracellular vesicles (EVs) are involved in a wide range of physiological and pathological processes by shuttling material out of and between cells. Tissue EVs may thus lend insights into disease mechanisms and also betray disease when released into easily accessed biological fluids. Since brain-derived EVs (bdEVs) and their cargo may serve as biomarkers of neurodegenerative diseases, we evaluated modifications to a published, rigorous protocol for separation of EVs from brain tissue and studied effects of processing variables on quantitative and qualitative outcomes. To this end, size exclusion chromatography (SEC) and sucrose density gradient ultracentrifugation were compared as final separation steps in protocols involving stepped ultracentrifugation. bdEVs were separated from brain tissues of human, macaque, and mouse. Effects of tissue perfusion and a model of post-mortem interval (PMI) before final bdEV separation were probed. MISEV2018-compliant EV characterization was performed, and both small RNA and protein profiling were done. We conclude that the modified, SEC-employing protocol achieves EV separation efficiency roughly similar to a protocol using gradient density ultracentrifugation, while decreasing operator time and, potentially, variability. The protocol appears to yield bdEVs of higher purity for human tissues compared with those of macaque and, especially, mouse, suggesting opportunities for optimization. Where possible, perfusion should be performed in animal models. The interval between death/tissue storage/processing and final bdEV separation can also affect bdEV populations and composition and should thus be recorded for rigorous reporting. Finally, different populations of EVs obtained through the modified method reported herein display characteristic RNA and protein content that hint at biomarker potential. To conclude, this study finds that the automatable and increasingly employed technique of SEC can be applied to tissue EV separation, and also reveals more about the importance of species-specific and technical considerations when working with tissue EVs. These results are expected to enhance the use of bdEVs in revealing and understanding brain disease.