Expression Of Adhesion Molecules Research Articles

Decreased proteasome function increases oxidative stress in the early stage of pressure ulcer development

The aging process in the elderly results in heightened skin fragility associated with various disorders, including pressure ulcers (PUs). Despite the high incidence of PUs in the elderly population, there is a limited body of research specifically examining the impact of aging on the development of pressure ulcers. Therefore, investigating age-related physiological abnormalities is essential to elucidate the pathogenesis of PUs. Ischemia-reperfusion (I/R) injury and the subsequent oxidative stress caused by reactive oxygen species (ROS) play essential roles in the early stage of PUs. In this study, we used a mouse model of proteasomal dysfunction with an age-related phenotype to examine the role of proteasome activity in cutaneous I/R injury in vivo. Decreased proteasome function did not affect the expression of inflammatory cytokines and adhesion molecules in the I/R area in transgenic mice; however, proteasome inhibition increased oxidative stress that was not attenuated by activation of the oxidative stress response mediated by NF-E2-related factor 2 (Nrf2). In dermal fibroblasts (FCs) subjected to hypoxia-reoxygenation (H/R), proteasome inhibition induced oxidative stress and ROS production, and Nrf2 activation did not adequately upregulate antioxidant enzyme expression, possibly leading to antioxidant/oxidant imbalance. The free radical scavenger edaravone had protective effects against I/R injury in vivo and decreased oxidative stress in FCs treated with a proteasome inhibitor and subjected to H/R in vitro. The results suggest that the age-related decline in proteasome activity promotes cutaneous I/R injury-induced oxidative stress, and free radical scavengers may exert protective effects by preventing oxidative stress in the early stage of PUs in elderly patients with impaired proteasome function.

Hepatocyte growth factor enhances the ability of dental pulp stem cells to ameliorate atherosclerosis in apolipoprotein E-knockout mice

BACKGROUND Atherosclerosis (AS), a chronic inflammatory disease of blood vessels, is a major contributor to cardiovascular disease. Dental pulp stem cells (DPSCs) are capable of exerting immunomodulatory and anti-inflammatory effects by secreting cytokines and exosomes and are widely used to treat autoimmune and inflammation-related diseases. Hepatocyte growth factor (HGF) is a pleiotropic cytokine that plays a key role in many inflammatory and autoimmune diseases. AIM To modify DPSCs with HGF (DPSC-HGF) and evaluate the therapeutic effect of DPSC-HGF on AS using an apolipoprotein E-knockout (ApoE-/-) mouse model and an in vitro cellular model. METHODS ApoE-/- mice were fed with a high-fat diet (HFD) for 12 wk and injected with DPSC-HGF or Ad-Null modified DPSCs (DPSC-Null) through tail vein at weeks 4, 7, and 11, respectively, and the therapeutic efficacy and mechanisms were analyzed by histopathology, flow cytometry, lipid and glucose measurements, real-time reverse transcription polymerase chain reaction (RT-PCR), and enzyme-linked immunosorbent assay at the different time points of the experiment. An in vitro inflammatory cell model was established by using RAW264.7 cells and human aortic endothelial cells (HAOECs), and indirect co-cultured with supernatant of DPSC-Null (DPSC-Null-CM) or DPSC-HGF-CM, and the effect and mechanisms were analyzed by flow cytometry, RT-PCR and western blot. Nuclear factor-κB (NF-κB) activators and inhibitors were also used to validate the related signaling pathways. RESULTS DPSC-Null and DPSC-HGF treatments decreased the area of atherosclerotic plaques and reduced the expression of inflammatory factors, and the percentage of macrophages in the aorta, and DPSC-HGF treatment had more pronounced effects. DPSCs treatment had no effect on serum lipoprotein levels. The FACS results showed that DPSCs treatment reduced the percentages of monocytes, neutrophils, and M1 macrophages in the peripheral blood and spleen. DPSC-Null-CM and DPSC-HGF-CM reduced adhesion molecule expression in tumor necrosis factor-α stimulated HAOECs and regulated M1 polarization and inflammatory factor expression in lipopolysaccharide-induced RAW264.7 cells by inhibiting the NF-κB signaling pathway. CONCLUSION This study suggested that DPSC-HGF could more effectively ameliorate AS in ApoE-/- mice on a HFD, and could be of greater value in stem cell-based treatments for AS.

Anti-Inflammatory Therapeutic Mechanisms of Isothiocyanates: Insights from Sulforaphane

Isothiocyanates (ITCs) belong to a group of natural products that possess a highly reactive electrophilic -N=C=S functional group. They are stored in plants as precursor molecules, glucosinolates, which are processed by the tyrosinase enzyme upon plant tissue damage to release ITCs, along with other products. Isolated from broccoli, sulforaphane is by far the most studied antioxidant ITC, acting primarily through the induction of a transcription factor, the nuclear factor erythroid 2–related factor 2 (Nrf2), which upregulates downstream antioxidant genes/proteins. Paradoxically, sulforaphane, as a pro-oxidant compound, can also increase the levels of reactive oxygen species, a mechanism which is attributed to its anticancer effect. Beyond highlighting the common pro-oxidant and antioxidant effects of sulforaphane, the present paper was designed to assess the diverse anti-inflammatory mechanisms reported to date using a variety of in vitro and in vivo experimental models. Sulforaphane downregulates the expression of pro-inflammatory cytokines, chemokines, adhesion molecules, cycloxyhenase-2, and inducible nitric oxide synthase. The signalling pathways of nuclear factor κB, activator protein 1, sirtuins 1, silent information regulator sirtuin 1 and 3, and microRNAs are among those affected by sulforaphane. These anti-inflammatory actions are sometimes due to direct action via interaction with the sulfhydryl structural moiety of cysteine residues in enzymes/proteins. The following are among the topics discussed in this paper: paradoxical signalling pathways such as the immunosuppressant or immunostimulant mechanisms; crosstalk between the oxidative and inflammatory pathways; and effects dependent on health and disease states.

Inflammation in HIV and Its Impact on Atherosclerotic Cardiovascular Disease.

People living with HIV have a 1.5- to 2-fold increased risk of developing cardiovascular disease. Despite treatment with highly effective antiretroviral therapy, people living with HIV have chronic inflammation that makes them susceptible to multiple comorbidities. Several factors, including the HIV reservoir, coinfections, clonal hematopoiesis of indeterminate potential (CHIP), microbial translocation, and antiretroviral therapy, may contribute to the chronic state of inflammation. Within the innate immune system, macrophages harbor latent HIV and are among the prominent immune cells present in atheroma during the progression of atherosclerosis. They secrete inflammatory cytokines such as IL (interleukin)-6 and tumor necrosis-α that stimulate the expression of adhesion molecules on the endothelium. This leads to the recruitment of other immune cells, including cluster of differentiation (CD)8+ and CD4+ T cells, also present in early and late atheroma. As such, cells of the innate and adaptive immune systems contribute to both systemic inflammation and vascular inflammation. On a molecular level, HIV-1 primes the NLRP3 (NLR family pyrin domain containing 3) inflammasome, leading to an increased expression of IL-1β, which is important for cardiovascular outcomes. Moreover, activation of TLRs (toll-like receptors) by HIV, gut microbes, and substance abuse further activates the NLRP3 inflammasome pathway. Finally, HIV proteins such as Nef (negative regulatory factor) can inhibit cholesterol efflux in monocytes and macrophages through direct action on the cholesterol transporter ABCA1 (ATP-binding cassette transporter A1), which promotes the formation of foam cells and the progression of atherosclerotic plaque. Here, we summarize the stages of atherosclerosis in the context of HIV, highlighting the effects of HIV, coinfections, and antiretroviral therapy on cells of the innate and adaptive immune system and describe current and future interventions to reduce residual inflammation and improve cardiovascular outcomes among people living with HIV.

#1449 Maturation of tertiary lymphoid structures in progressive kidney damage due to chronic phosphate load

Abstract Background and Aims We have recently shown that a high phosphate diet (HPD) in mice leads to an increase in FGF23 levels and causes progressive tubular damage and interstitial fibrosis with increased accumulation of macrophages and concomitant perivascular immune cell aggregates in the corticomedullary zone. Such tertiary lymphoid structures (TLS) can develop as a result of chronic inflammation and have already been described in lupus nephritis and IgA nephropathy, among others. In our model, the question arose to what extent damage to the proximal tubule is temporally associated with the development and maturation of TLS and which factors favor TLS development. Method Wild-type mice were fed HPD for 1, 2, 3, 4 and 6 months and the kidneys of each were compared with those of mice on a normal phosphate diet (NPD). To evaluate the effect of high FGF23 ± phosphate, Fgf23 was overexpressed in mice on NPD and HPD using an adeno-associated virus (AAV-Fgf23), and hypophosphatemic Hyp mice were used. Results An increased tubular damage score was seen after only two months of HPD. In parallel, perivascular immune cell clusters developed in the corticomedullary zone and in the renal cortex, which were characterized by aggregates of CD45R+ B cells and CD3+ T cells, as well as LYVE1+ lymphatic vessels after three months of HPD and were accompanied by increased expression of venous markers (Plvap, Aplnr, EphB4) and cell adhesion molecules (Sell, Vcam1, Madcam1). Further analyses showed a time-dependent induction of the immunofibroblast-derived chemokines Cxcl13 and Ccl19, as well as the lymphotoxins Lta and Ltb, which are important for the differentiation of immunofibroblasts into follicular dendritic cells (FDC) and follicular reticular cells (FRC). Already after four months of HPD, proliferating B-cell clusters with FDCs, FRCs located in T-cell clusters, podoplanin+ networks, high endothelial venules, plasma cells and increased IgD synthesis indicated fully mature TLS, while tubular damage and fibrosis continued to increase until six months of HPD. Compared to AAV-Fgf23 mice on NPD, only AAV-Fgf23 animals on HPD developed tubular damage with fibrosis and fully mature TLS. Hypophosphatemic Hyp mice with high FGF23 showed neither signs of tubular damage nor the development of TLS. Conclusion The development of renal TLS due to chronic high phosphate load coincides with the development of tubular damage, with earlier maturation of TLS and progression of tubular damage.

#1227 The role of P-selectin (CD62P) expression in renal tissue in the development of diabetic nephropathy

Abstract Background and Aims The prevalence of diabetic nephropathy (DN) is increasing in line with the increase in the incidence of diabetes mellitus (DM) worldwide. The latest data from the International Diabetes Federation (IDF) predicts that by 2045, more than 10.5% of adults worldwide will have diabetes. This will lead to kidney damage in 100-250 million people. DN is characterized by structural and functional changes. As a result of chronic hyperglycemia, pathogenic changes in the vascular wall develop, and the frequency of micro- and macrovascular complications associated with morbidity and mortality among patients with diabetes increases. However, the exact mechanism of vascular complications is not completely clear. Endothelial dysfunction plays a key role in triggering the development of inflammatory mechanisms that are associated with vascular complications in patients with type 2 diabetes mellitus (T2DM). Activation of the endothelium due to increased release of cytokines and expression of adhesion molecules promotes platelet activation and their adhesion to the activated endothelium. Selectins (E-selectin, L-selectin and P-selectin) play a major role in the development of microvascular complications. The aim of the study was to examine the role of P-selectin (CD62p) expression in the glomerular endothelium and peritubular capillaries in patients with different morphological classes of DN and to evaluate its effect on the development and progression of morphological changes in renal tissue. Method Was examined 49 patients with T2DM complicated by the development of DN. The average age of the patients was 66.58 ± 3.27 years. There were 35 women, 14 men. The duration of the disease was 17.70 ± 0.35 years. The duration of DN from the moment of detection of microalbuminuria to the morphological examination of the renal tissue and diagnosis was 1.65 ± 0.34 years. All patients underwent light and immunofluorescence microscopy of kidney tissue biopsies obtained by intravital puncture biopsy. Morphological changes in tissue were assessed in accordance with the latest international classification of diabetic nephropathy developed by the Scientific Committee of the Pathology Society, USA. According to light microscopy data, class IIa (mild mesangial expansion) was detected in 12 patients, class IIb (severe mesangial expansion) in 14 patients, class III (Kimmelstil–Wilson nodular lesions) in 19 patients, and class IV (advanced diabetic glomerulosclerosis) in 5 patients. In addition to light microscopy, the expression of CD62β (P-selectin) in the glomerular endothelium and in peritubular capillaries was determined in all patients. FITc-labeled monoclonal antibodies (FITC anti-human CD62p Antibody, clone AK4 Cat#304904), were used (Biolegend, USA). Results Analysis of biopsy tissue from DN patients showed that CD62p expression is detected both in the glomerular endothelium (1.6383 ± 0.4789 (95% CI: 0.9574-2.7234)) and in peritubular capillaries (1.1702 ± 0.1308 (95% CI: 0.9149–1.4250)). Using the linear regression method with the calculation of the coefficients of determination R2 (R Square), the values of the F criterion, significant regression models were obtained: Expression of CD62p in the glomerular endothelium promotes the development and progression of arteriolar hyalinosis (R2=0.213, F=12.476 p=0.001); expansion of the mesangial matrix (R2=0.362, F=26.09, p=0.0001); thickening of the basement membrane (R2=0.127, F=6.57, p=0.014); development and progression of nodular Kimmelstiel–Wilson lesions (R2=0.106, F=5.360, p=0.025). Expression of CD62p in peritubular capillaries promotes the development of interstitial sclerosis (R2=0.549, F=54.732, p=0.0001). The severity of CD62p expression in the glomerular endothelium depends on the morphological class of DN in patients (R2=0.216, F=12.684, p=0.001). Conclusion

Exploration on the effect of anserine on the alleviation of DVT and its molecular mechanism

BackgroundThis study aimed to explore the regulatory effect of anserine on HUVEC cell injury and thrombosis in deep venous thrombosis (DVT) rats, and to elucidate the underlying molecular mechanisms.MethodsNon-targeted metabolomics data analyses were conducted using an ultra-performance liquid chromatography system Vanquish UHPLC and mass spectrometer to detect plasma metabolism profiles. The transcriptome sequencing and gene intervention experiments were performed to verify the regulatory effect. Further in vivo and in vitro experiments were performed. Enzyme-linked immunosorbent assay was used to detect the levels of P-selectin, E-selectin, and vWF, hematoxylin-eosin (HE) staining was performed to observe thrombotic and inflammatory cell infiltration, flow cytometry and TUNEL assays were performed to detect apoptosis, and qPCR and WB assays were conducted to determine the gene and protein expression.ResultsAnserine alleviated HUVECs injury, reduced adhesion molecule expression, and inflammation. It decreased P-selectin, E-selectin, vWF, THBD, TFPI levels, and apoptosis while promoting NOS3, ET-1, and NO release in HUVECs. In DVT rats, anserine reduced P-selectin, E-selectin, vWF, thrombosis, cell infiltration, apoptosis, and promoted NO release. Transcriptome sequencing and gene intervention confirmed anserine’s regulation of the PI3K-Akt pathway and coagulation via MYB. CARNMT1, a regulatory enzyme for anserine metabolism, increased anserine content, inhibiting coagulation, thrombosis, cell infiltration, and promoting NO release in rats.ConclusionThis study confirmed anserine could alleviate DVT by improving the inflammatory response, inhibiting blood agglutination, and promoting vasodilation, providing new potential therapeutic targets, important scientific evidence for the development of DVT management, and new clues for an in-depth understanding of its molecular mechanisms.

Epithelial Cell Adhesion Molecule (EpCAM) Expression in Human Tumors: A Comparison with Pan-Cytokeratin and TROP2 in 14,832 Tumors.

EpCAM is expressed in many epithelial tumors and is used for the distinction of malignant mesotheliomas from adenocarcinomas and as a surrogate pan-epithelial marker. A tissue microarray containing 14,832 samples from 120 different tumor categories was analyzed by immunohistochemistry. EpCAM staining was compared with TROP2 and CKpan. EpCAM staining was detectable in 99 tumor categories. Among 78 epithelial tumor types, the EpCAM positivity rate was ≥90% in 60 categories-including adenocarcinomas, neuroendocrine neoplasms, and germ cell tumors. EpCAM staining was the lowest in hepatocellular carcinomas, adrenocortical tumors, renal cell neoplasms, and in poorly differentiated carcinomas. A comparison of EpCAM and CKpan staining identified a high concordance but EpCAM was higher in testicular seminomas and neuroendocrine neoplasms and CKpan in hepatocellular carcinomas, mesotheliomas, and poorly differentiated non-neuroendocrine tumors. A comparison of EpCAM and TROP2 revealed a higher rate of TROP2 positivity in squamous cell carcinomas and lower rates in many gastrointestinal adenocarcinomas, testicular germ cell tumors, neuroendocrine neoplasms, and renal cell tumors. These data confirm EpCAM as a surrogate epithelial marker for adenocarcinomas and its diagnostic utility for the distinction of malignant mesotheliomas. In comparison to CKpan and TROP2 antibodies, EpCAM staining is particularly common in seminomas and in neuroendocrine neoplasms.

Rapamycin Induces Phenotypic Alterations in Oral Cancer Cells That May Facilitate Antitumor T Cell Responses.

In this study, we investigated the antitumor immunomodulatory effects of rapamycin in oral cancer. We examined the proliferation, apoptosis, and migration of cancer cells and investigated the cell surface expression levels of immune accessory molecules and T cell immune responses in vitro. We investigated the effect of in vivo administration of rapamycin on immune cell distribution and T cell immune responses in oral tumor-bearing mice. Rapamycin treatment significantly inhibited OSCC cell proliferation and migration, increased apoptotic cell death, and upregulated cell surface expression of several immune accessory and adhesion molecules, including CD40, CD83, PD-L1, PD-L2, MHC class I, P-selectin, and VCAM-1. These cancer cells augmented T cell proliferation. In vivo rapamycin administration significantly attenuated mouse tumor growth with an increased proportion of immune cells, including CD4+ T cells, CD8+ T cells, and dendritic cells (DCs); decreased the proportion of immune suppressive cells, such as myeloid-derived suppressor cells and regulatory T cells; enhanced DC maturation and upregulated the surface expression of CD40, CD86, and ICAM-1. Our results suggest that the therapeutic effect of mTOR inhibition in oral cancer can cause direct antitumor and immunomodulatory effects.

Genomic Insights Into Enterococcus mundtii 203: A Promising Probiotic Candidate Isolated From Camel Feces.

Enterococcus, a common commensal organism in the human gut, exhibits a dual nature with certain strains offering probiotic benefits, while others are associated with nosocomial infections. In this study, we conducted a comprehensive examination of the genome of Enterococcus mundtii strain 203 to assess its probiotic potential and safety profile. The complete genome sequencing, assembly, and annotation were performed, followed by bioinformatics analysis. Our investigation reveals a detailed characterization of the Enterococcus mundtii 203 genome, originally isolated from camel feces, with a size of 3,053,234 bases and a GC content of 38.4%. Importantly, our analysis suggests that this strain poses no risk as a human pathogen due to the absence of antibiotic resistance determinants and virulence factors. The genome harbors a multitude of genes responsible for lactic acid production, bioactive peptide synthesis, adhesion molecule expression, resistance to harsh gut conditions, and enhancement of host metabolism. These findings underline the potential probiotic functionality of Enterococcus mundtii 203, positioning it as a promising candidate. Notably, our study did not identify any sequences related to insertion elements or CRISPR-Cas fragments.

Breast Cancer Conditioned Media Modulate the Expression of Immune Checkpoints and Adhesion Molecules in Endothelial Cells

Breast Cancer Conditioned Media Modulate the Expression of Immune Checkpoints and Adhesion Molecules in Endothelial Cells

Angiogenic potential in periodontal stem cells from upper and lower jaw: A pilot study.

Teeth and supporting oral tissues are attractive and accessible sources of stem cells. Periodontal ligament stem cells (PDLSC) are readily isolated from extracted third molars, and exhibit the ability to self-renew and differentiate into multiple mesodermal cell fates. Clinical experience suggests that the exact location of periodontal defects affects the oral bone remodeling and wound healing. Compared to the mandible, the maxilla heals quicker and more efficiently. Angiogenesis is key in tissue regeneration including dental tissues, yet few studies focus on the angiogenic potential of PDLSC, none of which considered the differences between upper and lower jaw PDLSC (u-PDLSC and l-PDLSC, respectively). Here we studied the angiogenic potential of u-PDLSC and l-PDLSC and compared the results to well-established mesenchymal stem cells (MSC). Cells were characterized in terms of surface markers, proliferation, and vascular endothelial growth factor (VEGF) secretion, and angiogenic assays were performed. Newly formed capillaries were stained with CD31, and their expression of platelet endothelial cell adhesion molecule (PECAM-1), angiopoietin 2 (ANGPT2), and vascular endothelial growth factor receptor 1 and 2 (VEGFR-1, VEGFR-2) were measured. Periodontal stem cells from the upper jaw showed a higher proliferation capacity, secreted more VEGF, and formed capillary networks faster and denser than l-PDLSC. Gene expression of angiogenesis-related genes was significantly higher in u-PDLSC than in l-PDLSC or MSC, given that culture conditions were suitable. The oral cavity is a valuable source of stem cells, particularly PDLSC, which are promising for oral tissue engineering due to their robust growth, lifelong accessibility, low immunogenicity, and strong differentiation potential. Notably, u-PDLSC exhibit higher VEGF secretion and accelerate capillary formation compared to l-PDLSC or MSC. This study suggests a potential molecular mechanism in capillary formation, emphasizing the significance of precise location isolation of PDLSC.

Content and tissue expression of Collagen I, Collagen IV, and Laminin in the Extracellular Matrix in Prostate Adenocarcinoma.

Prostate cancer is one of the most common neoplasm in the male population. It is not known why some tumors become more aggressive than others. Although most studies show changes in the expression of cell adhesion molecules and the extracellular matrix correlated with the Gleason score, no study has objectively measured the tissue content of these molecules. This study aims to measure the content and tissue expression of collagen type I and IV and laminin in the extracellular matrix of patients with prostate adenocarcinoma and correlate these findings with the Gleason score and clinical characteristics. Forty-one patients who underwent radical prostate surgery at the Urology Department of a reference Hospital in Brazil between January 2015 and December 2020 were studied. The tissue protein content was estimated under light microscopy at a final magnification of 200 × . The mean collagen I score in prostate adenocarcinoma tissue samples was 7.16 ± 1.03 pixels/field. The mean type IV collagen score was 3.44 ± 0.61 pixels/field. The mean laminin score was 5.19 ± 0.79 pixels/field. The total Gleason score was correlated with both collagen and laminin. All the correlations were negative, which shows that the higher the collagen/laminin expression was, the lower the total Gleason score (p-value < 0,05). According to the Pearson correlation analysis, age has no statistical relationship with collagen and laminin content. PSA, in turn, showed a correlation only with laminin, but r = -0.378 (p = 0.015). Among the associated diseases and lifestyle habits, there is only statistical significance in the comparison of alcoholism for collagen I. For collagen IV and laminin, no statistical significance was obtained with the clinical variables analyzed.

17β-estradiol and methylprednisolone association as a therapeutic option to modulate lung inflammation in brain-dead female rats.

Brain death (BD) is known to compromise graft quality by causing hemodynamic, metabolic, and hormonal changes. The abrupt reduction of female sex hormones after BD was associated with increased lung inflammation. The use of both corticoids and estradiol independently has presented positive results in modulating BD-induced inflammatory response. However, studies have shown that for females the presence of both estrogen and corticoids is necessary to ensure adequate immune response. In that sense, this study aims to investigate how the association of methylprednisolone (MP) and estradiol (E2) could modulate the lung inflammation triggered by BD in female rats. Female Wistar rats (8 weeks) were divided into four groups: sham (animals submitted to the surgical process, without induction of BD), BD (animals submitted to BD), MP/E2 (animals submitted to BD that received MP and E2 treatment 3h after BD induction) and MP (animals submitted to BD that received MP treatment 3h after BD induction). Hemodynamics, systemic and local quantification of IL-6, IL-1β, VEGF, and TNF-α, leukocyte infiltration to the lung parenchyma and airways, and adhesion molecule expression were analyzed. After treatment, MP/E2 association was able to reinstate mean arterial pressure to levels close to Sham animals (p<0.05). BD increased leukocyte infiltration to the airways and MP/E2 was able to reduce the number of cells (p=0.0139). Also, the associated treatment modulated the vasculature by reducing the expression of VEGF (p=0.0616) and maintaining eNOS levels (p=0.004) in lung tissue. Data presented in this study show that the association between corticoids and estradiol could represent a better treatment strategy for lung inflammation in the female BD donor by presenting a positive effect in the hemodynamic management of the donor, as well as by reducing infiltrated leukocyte to the airways and release of inflammatory markers in the short and long term.

Endothelial dysfunction in neurodegenerative disease: Is endothelial inflammation an overlooked druggable target?

Neurological diseases with a neurodegenerative component have been associated with alterations in the cerebrovasculature. At the anatomical level, these are centred around changes in cerebral blood flow and vessel organisation. At the molecular level, there is extensive expression of cellular adhesion molecules and increased release of pro-inflammatory mediators. Together, these has been found to negatively impact blood-brain barrier integrity. Systemic inflammation has been found to accelerate and exacerbate endothelial dysfunction, neuroinflammation and degeneration. Here, we review the role of cerebrovasculature dysfunction in neurodegenerative disease and discuss the potential contribution of intermittent pro-inflammatory systemic disease in causing endothelial pathology, highlighting a possible mechanism that may allow broad-spectrum therapeutic targeting in the future.

Regnase-1 D141N mutation induces CD4+ T cell-mediated lung granuloma formation via upregulation of Pim2.

Regnase-1 is an RNase that plays a critical role in negatively regulating immune responses by destabilizing inflammatory mRNAs. Dysfunction of Regnase-1 can be a major cause of various inflammatory diseases with tissue injury and immune cell infiltration into organs. This study focuses on the role of RNase activity of Regnase-1 in developing inflammatory diseases. We have constructed mice with a single point mutation at the catalytic center of Regnase-1 RNase domain, which lacks endonuclease activity. D141N mutant mice demonstrated systemic inflammation, immune cell infiltration into various organs and progressive development of lung granuloma. CD4+ T cells, mainly affected by this mutation, upregulated mTORC1 pathway and facilitated the autoimmune trait in D141N mutation. Moreover, serine/threonine kinase Pim2 contributed to lung inflammation in this mutation. Inhibition of Pim2 kinase activity ameliorated granulomatous inflammation, immune cell infiltration and proliferation in the lungs. Additionally, Pim2 inhibition reduced the expression of adhesion molecules on CD4+ T cells, suggesting a role for Pim2 in facilitating leukocyte adhesion and migration to inflamed tissues. Our findings provide new insights into the role of Regnase-1 RNase activity in controlling immune function and underscore the therapeutic relevance of targeting Pim2 to modulate abnormal immune responses.

LIF-STAT in decidual cells: possible role in embryo implantation and early pregnancy.

In this study, we investigate the effects of microRNA-138-5p and GPR124-regulated inflammasome and downstream LIF-STAT and adhesion molecules signaling in human decidual stromal cells. After informed consent was obtained from women aged 25-38 years undergoing surgical termination of the normal pregnancy and spontaneous miscarriage after 6-9 weeks of gestation, human decidual stromal cells were separated from the decidual tissue. Extracellular vesicles with microRNA (miRNA) between cells have been regarded as critical factors for embryo-maternal interactions on embryo implantation and programming of human pregnancy. MicroRNA-138-5p acts as the transcriptional regulator of GPR124 and the mediator of downstream inflammasome. LIF-regulated STAT activation and expression of integrins might influence embryo implantation. Hence, a better understanding of LIF-STAT and adhesion molecules signaling would elucidate the mechanism of microRNA-138-5p- and GPR124-regulated inflammasome activation on embryo implantation and pregnancy. Our results show the purified extracellular vesicles from decidual stromal cells, the microRNA-138-5p-inhibited GPR124 and inflammasome expression, and microRNA-138-5p activated the expression of LIF-STAT and adhesion molecules in human decidual stromal cells. Additionally, the knockdown of GPR124 and NLRP3 through siRNA increases the expression of LIF-STAT and adhesion molecules. Our findings reveal a better understanding the role of extracellular vesicles, microRNA-138-5p, GPR124, inflammasome, and LIF-STAT and adhesion molecules in embryo implantation and programming of human pregnancy.

A human pluripotent stem cell-derived in vitro model of the blood–brain barrier in cerebral malaria

BackgroundBlood–brain barrier (BBB) disruption is a central feature of cerebral malaria (CM), a severe complication of Plasmodium falciparum (Pf) infections. In CM, sequestration of Pf-infected red blood cells (Pf-iRBCs) to brain endothelial cells combined with inflammation, hemolysis, microvasculature obstruction and endothelial dysfunction mediates BBB disruption, resulting in severe neurologic symptoms including coma and seizures, potentially leading to death or long-term sequelae. In vitro models have advanced our knowledge of CM-mediated BBB disruption, but their physiological relevance remains uncertain. Using human induced pluripotent stem cell-derived brain microvascular endothelial cells (hiPSC-BMECs), we aimed to develop a novel in vitro model of the BBB in CM, exhibiting enhanced barrier properties.MethodshiPSC-BMECs were co-cultured with HB3var03 strain Pf-iRBCs up to 9 h. Barrier integrity was measured using transendothelial electrical resistance (TEER) and sodium fluorescein permeability assays. Localization and expression of tight junction (TJ) proteins (occludin, zonula occludens-1, claudin-5), cellular adhesion molecules (ICAM-1, VCAM-1), and endothelial surface markers (EPCR) were determined using immunofluorescence imaging (IF) and western blotting (WB). Expression of angiogenic and cell stress markers were measured using multiplex proteome profiler arrays.ResultsAfter 6-h of co-culture with Pf-iRBCs, hiPSC-BMECs showed reduced TEER and increased sodium fluorescein permeability compared to co-culture with uninfected RBCs, indicative of a leaky barrier. We observed disruptions in localization of occludin, zonula occludens-1, and claudin-5 by IF, but no change in protein expression by WB in Pf-iRBC co-cultures. Expression of ICAM-1 and VCAM-1 but not EPCR was elevated in hiPSC-BMECs with Pf-iRBC co-culture compared to uninfected RBC co-culture. In addition, there was an increase in expression of angiogenin, platelet factor-4, and phospho-heat shock protein-27 in the Pf-iRBCs co-culture compared to uninfected RBC co-culture.ConclusionThese findings demonstrate the validity of our hiPSC-BMECs based model of the BBB, that displays enhanced barrier integrity and appropriate TJ protein localization. In the hiPSC-BMEC co-culture with Pf-iRBCs, reduced TEER, increased paracellular permeability, changes in TJ protein localization, increase in expression of adhesion molecules, and markers of angiogenesis and cellular stress all point towards a novel model with enhanced barrier properties, suitable for investigating pathogenic mechanisms underlying BBB disruption in CM.

A novel dual inhibitor of the angiotensin and endothelin systems for the treatment of hypertension

Hypertension, affecting nearly half of the US adult population, is a primary cause of morbidity and mortality worldwide. Despite the availability of several classes of antihypertensive medications, only 25% of patients have their blood pressure under control, highlighting the need for novel antihypertensive therapeutics with better effcacy. Among hypertensive cases, salt-sensitive and drug-resistant hypertension are particularly concerning, as they are unresponsive to a combined regimen of three or more classes of medications, including angiotensin II (Ang II) receptor blockers (ARBs), angiotensin-converting enzyme inhibitors (ACEis), and diuretics. Salt-sensitive, observed in 50% of the general and 73% of black hypertensive patients, disproportionately affects the latter, leading to significantly higher mortality. Salt-sensitive hypertension in humans, as well as in various experimental models of hypertension (e.g., Ang II-induced, Dahl-salt sensitive [DSS] rats, deoxycorticosterone acetate [DOCA]-salt hypertensive rats), is characterized by significantly elevated levels of plasma endothelin-1 (ET-1), oxidative stress, and kidney dysfunction. ET-1 is often considered a final common pathway in orchestrating cardiovascular dysfunction through a range of proinflammatory mediators such as Ang II, cytokines, hypoxia, thrombin, reactive oxygen species (ROS), oxidized LDL, and vasopressin, all of which stimulate ET-1 production. In this capacity, we report the discovery of a gut microbiota-derived metabolite, indole-3-acetic acid (IAA), that simultaneously blocks ET-1 receptors (ETAR and ETBR) and the ET-biosynthetic enzyme ECE-1. Our data demonstrate that IAA inhibits ET-1-induced constriction of resistance mesenteric arteries, ROS production in human aortic smooth muscle cells, activation of cultured endothelial cells, adhesion molecule expression, and leukocyte adhesion. IAA inhibited purified human ECE-1 and suppressed Ang-II-induced and hypoxia-elicited ET-1 production from endothelial cells in vitro. Administration of a once-daily, extended-release formulation of IAA inhibits blood pressure elevation and kidney dysfunction in both DSS and Ang II-induced hypertension. IAA treatment preserved endothelial nitric oxide (NO) production and maintained smooth muscle sensitivity to a NO donor, sodium nitroprusside. Furthermore, IAA inhibited the expression of ROS-associated proteins such as Nox2 and Nox4, reduced oxidative damages, and decreased the production of ET-1 in vivo. Overall, IAA is the first compound that, through novel dual targeting of both the angiotensin and endothelin systems, demonstrates profound antihypertensive action in both salt-sensitive and angiotensin II-induced hypertension. Thus, IAA has the potential to effectively treat hypertension that does not respond to conventional therapies. American Heart Association. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

PM2.5 Temporally Decreases Human Brain Endothelial Barrier Proteins and Concomitantly Increases Inflammation and Autophagy in a Dose Dependent Manner

Exposure to airborne particulate matter 2.5 (particle size &lt;PM2.5 um) pollution is a significant co-morbidity for stroke and other cardio- and cerebrovascular diseases, causing premature mortality. However, mechanisms underlying PM2.5-mediated endothelial dysfunction and integrity loss are not known. Our goal was to elucidate how PM2.5 alters brain endothelial phenotype causing inflammation and loss of barrier integrity to provide better insight to the potential pathogenesis of PM2.5. We hypothesized that PM2.5 would alter integral endothelial barrier proteins as well as inflammatory mediators in a dose and temporal dependent manner, subsequently exacerbating the impact of acute ischemic-like injury. Primary adult male human brain microvascular endothelial cells (HBMEC) were preconditioned with PM2.5 (300, 75, or 15 μg/m3; 12, 24, or 36h) or vehicle, then exposed to normoxia (21% O2) or ischemic-like injury, hypoxia plus glucose deprivation (HGD; 1% O2), for 3h. HBMEC barrier function was assessed via trans-endothelial electrical resistance (TEER). HBMEC levels or expression of barrier markers (claudin-5, occludin, ZO-1), adhesion molecules (ICAM-1 and PECAM-1), inflammatory proteins (iNOS, COX-2, LOX-1, TNF-α, IL-1β), and autophagic protein (Beclin-1) were examined using qRT-PCR, in cell western, and standard immunoblotting. Ischemia-like injury as well as PM2.5 decreased HBMEC barrier function. PM2.5 also induced a concomitant temporal and dose dependent decrease in claudin-5 and increase in iNOS as well as TNF-α levels. Additionally, PM2.5 increased protein levels of beclin-1 and LOX-1 like that of HGD alone; however, combination of PM2.5 and HGD decreased levels of beclin-1. HGD alone or in combination with PM2.5 decreased levels of PECAM-1, but PM2.5 alone did not alter PECAM-1. PM2.5 in the presence or absence of HGD induced differential alteration in claudin-5 isoform protein levels. Intriguingly, PM2.5 decreased claudin-5 mRNA levels like that observed in HBMECs exposed to HGD alone. PM2.5 plus HGD significantly increased mRNA levels of both ICAM-1 and IL-1β. In conclusion, PM2.5 mediated inflammatory and vascular pathogenesis involves a potential complex intracellular molecular framework associated with the brain endothelium which is compounded by ischemic like injury. These findings have revealed detrimental effects of PM2.5 on the brain vascular endothelium which will help to identify targets in the endothelium to restore or preserve cerebrovascular homeostasis. University of Arizona Valley Research Partnership Grant VRP37 P2 (RJG), American Heart Association 19AIREA34480018 (RJG), UA VRP Grant VRP55 P1a (TSW). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.