Loss of fatty acid binding protein 3 ameliorates lipopolysaccharide-induced inflammation and endothelial dysfunction.

Circulating fatty acid-binding protein 3 (FABP3) is an effective biomarker of myocardial injury and peripheral artery disease (PAD). The endothelium, which forms the inner most layer of every blood vessel, is exposed to higher levels of FABP3 in PAD or following myocardial injury, but the pathophysiological role of endothelial FABP3, the effect of FABP3 exposure on endothelial cells, and related mechanisms are unknown. Here, we aimed to evaluate the pathophysiological role of endothelial FABP3 and related mechanisms in vitro. Our molecular and functional in vitro analyses show that (1) FABP3 is basally expressed in endothelial cells; (2) inflammatory stress in the form of lipopolysaccharide (LPS) upregulated endothelial FABP3 expression; (3) loss of endogenous FABP3 protected endothelial cells against LPS-induced endothelial dysfunction; however, exogenous FABP3 exposure exacerbated LPS-induced inflammation; (4) loss of endogenous FABP3 protected against LPS-induced endothelial dysfunction by promoting cell survival and anti-inflammatory and pro-angiogenic signaling pathways. Together, these findings suggest that gain-of endothelial FABP3 exacerbates, whereas loss-of endothelial FABP3 inhibits LPS-induced endothelial dysfunction by promoting cell survival and anti-inflammatory and pro-angiogenic signaling. We propose that an increased circulating FABP3 in myocardial injury or PAD patients may be detrimental to endothelial function, and therefore, therapies aimed at inhibiting FABP3 may improve endothelial function in diseased states.

DNA damage response signaling: A common link between cancer and cardiovascular diseases.

DNA damage response (DDR) signaling ensures genomic and proteomic homeostasis to maintain a healthy genome. Dysregulation either in the form of down- or upregulation in the DDR pathways correlates with various pathophysiological states, including cancer and cardiovascular diseases (CVDs). Impaired DDR is studied as a signature mechanism for cancer; however, it also plays a role in ischemia-reperfusion injury (IRI), inflammation, cardiovascular function, and aging, demonstrating a complex and intriguing relationship between cancer and pathophysiology of CVDs. Accordingly, there are increasing number of reports indicating higher incidences of CVDs in cancer patients. In the present review, we thoroughly discuss (1) different DDR pathways, (2) the functional cross talk among different DDR mechanisms, (3) the role of DDR in cancer, (4) the commonalities and differences of DDR between cancer and CVDs, (5) the role of DDR in pathophysiology of CVDs, (6) interventional strategies for targeting genomic instability in CVDs, and (7) future perspective.

Endothelial cell-specific loss of eNOS differentially affects endothelial function.

The endothelium maintains and regulates vascular homeostasis mainly by balancing interplay between vasorelaxation and vasoconstriction via regulating Nitric Oxide (NO) availability. Endothelial nitric oxide synthase (eNOS) is one of three NOS isoforms that catalyses the synthesis of NO to regulate endothelial function. However, eNOS's role in the regulation of endothelial function, such as cell proliferation and migration remain unclear. To gain a better understanding, we genetically knocked down eNOS in cultured endothelial cells using sieNOS and evaluated cell proliferation, migration and also tube forming potential in vitro. To our surprise, loss of eNOS significantly induced endothelial cell proliferation, which was associated with significant downregulation of both cell cycle inhibitor p21 and cell proliferation antigen Ki-67. Knockdown of eNOS induced cell migration but inhibited formation of tube-like structures in vitro. Mechanistically, loss of eNOS was associated with activation of MAPK/ERK and inhibition of PI3-K/AKT signaling pathway. On the contrary, pharmacologic inhibition of eNOS by inhibitors L-NAME or L-NMMA, inhibited cell proliferation. Genetic and pharmacologic inhibition of eNOS, both promoted endothelial cell migration but inhibited tube-forming potential. Our findings confirm that eNOS regulate endothelial function by inversely controlling endothelial cell proliferation and migration, and by directly regulating its tube-forming potential. Differential results obtained following pharmacologic versus genetic inhibition of eNOS indicates a more complex mechanism behind eNOS regulation and activity in endothelial cells, warranting further investigation.

Transcriptomics of angiotensin II-induced long noncoding and coding RNAs in endothelial cells.

OBJECTIVE: Angiotensin II (Ang II)-induced endothelial dysfunction plays an important role in the pathogenesis of cardiovascular diseases such as systemic hypertension, cardiac hypertrophy and atherosclerosis. Recently, long noncoding RNAs (lncRNAs) have been shown to play an essential role in the pathobiology of cardiovascular diseases; however, the effect of Ang II on lncRNAs and coding RNAs expression in endothelial cells has not been evaluated. Accordingly, we sought to evaluate the expression profiles of lncRNAs and coding RNAs in endothelial cells following treatment with Ang II. METHODS: Human umbilical vein endothelial cells (HUVECs) were cultured and treated with Ang II (10-6 mol/l) for 24 h. The cells were then profiled for the expression of lncRNAs and mRNAs using the Arraystar Human lncRNA Expression Microarray V3.0. RESULTS: In HUVECs following Ang II treatment, from a total of 30 584 lncRNA targets screened, 25 targets were significantly upregulated, while 69 were downregulated. In the same HUVECs samples, from 26 106 mRNA targets screened, 28 targets were significantly upregulated and 67 were downregulated. Of the differentially expressed lncRNAs, RP11-354P11.2 and RP11-360F5.1 were the most upregulated (11-fold) and downregulated (three-fold) lncRNAs, respectively. Assigning the differentially regulated genes into functional groups using bioinformatics reveals numerous genes involved in the nucleotide excision repair and ECM-receptor interaction. CONCLUSION: This is the first study to profile the Ang II-induced differentially expressed lncRNAs and mRNAs in human endothelial cells. Our results reveal novel targets and substantially extend the list of potential candidate genes involved in Ang II-induced endothelial dysfunction and cardiovascular diseases.

Interleukin-1 in COVID-19 Infection: Immunopathogenesis and Possible Therapeutic Perspective.

The newfound coronavirus disease 2019 (COVID-19), initiated by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an international public health concern, threatening the lives of millions of people worldwide. The virus seems to have a propensity to infect older males, especially those with underlying diseases. The cytokine storm following hyperactivated immune responses due to SARS-CoV-2 infection is probably the crucial source of severe pneumonia that leads to acute lung injury, systemic inflammatory response syndrome, or acute respiratory distress syndrome, and finally multiple organ dysfunction syndromes, as well as death in many cases. Several studies revealed that interleukin (IL)-1ß levels were elevated during COVID-19 infection. In addition, the IL-1 cytokine family has a pivotal role in the induction of cytokine storm due to uncontrolled immune responses in COVID-19 infection. This article reviews the role of IL-1 in inflammation and utilization of IL-1 inhibitor agents in controlling the inflammatory outcomes initiated by SARS-CoV-2 infection.

Immunopharmacological perspective on zinc in SARS-CoV-2 infection.

The novel SARS-CoV-2 which was first reported in China is the cause of infection known as COVID-19. In comparison with other coronaviruses such as SARS-CoV and MERS, the mortality rate of SARS-CoV-2 is lower but the transmissibility is higher. Immune dysregulation is the most common feature of the immunopathogenesis of COVID-19 that leads to hyperinflammation. Micronutrients such as zinc are essential for normal immune function. According to the assessment of WHO, approximately one-third of the world's society suffer from zinc deficiency. Low plasma levels of zinc are associated with abnormal immune system functions such as impaired chemotaxis of polymorphonuclear cells (PMNs) and phagocytosis, dysregulated intracellular killing, overexpression of the inflammatory cytokines, lymphopenia, decreased antibody production, and sensitivity to microbes especially viral respiratory infections. Zinc exerts numerous direct and indirect effects against a wide variety of viral species particularly RNA viruses. The use of zinc and a combination of zinc-pyrithione at low concentrations impede SARS-CoV replication in vitro. Accordingly, zinc can inhibit the elongation step of RNA transcription. Furthermore, zinc might improve antiviral immunity by up-regulation of IFNα through JAK/STAT1 signaling pathway in leukocytes. On the other hand, zinc supplementation might ameliorate tissue damage caused by mechanical ventilation in critical COVID-19 patients. Finally, zinc might be used in combination with antiviral medications for the management of COVID-19 patients. In the current review article, we review and discuss the immunobiological roles and antiviral properties as well as the therapeutic application of zinc in SARS-CoV-2 and related coronaviruses infections.

Neurological manifestations of COVID-19: with emphasis on Iranian patients.

The novel coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has instigated a global pandemic as a formidable and highly contagious infectious disease. Although the respiratory system remains the most frequently affected organ, several case reports have revealed that the complications are not merely limited to the respiratory system, and neurotropic and neuroinvasive properties have also been observed, leading to neurological diseases. In the present paper, it was intended to review the possible neuroinvasive routes of SARS-CoV-2 and its mechanisms that may cause neurological damage. Additionally, the neurological manifestations of COVID-19 across the globe were discussed with emphasis on Iran, while highlighting the impact of SARS-CoV-2 on the central and peripheral nervous systems.

Dexosomes as a cell-free vaccine for cancer immunotherapy.

Dendritic cells (DCs) secrete vast quantities of exosomes termed as dexosomes. Dexosomes are symmetric nanoscale heat-stable vesicles that consist of a lipid bilayer displaying a characteristic series of lipid and protein molecules. They include tetraspanins and all established proteins for presenting antigenic material such as the major histocompatibility complex class I/II (MHC I/II) and CD1a, b, c, d proteins and CD86 costimulatory molecule. Dexosomes contribute to antigen-specific cellular immune responses by incorporating the MHC proteins with antigen molecules and transferring the antigen-MHC complexes and other associated molecules to naïve DCs. A variety of ex vivo and in vivo studies demonstrated that antigen-loaded dexosomes were able to initiate potent antitumor immunity. Human dexosomes can be easily prepared using monocyte-derived DCs isolated by leukapheresis of peripheral blood and treated ex vivo by cytokines and other factors. The feasibility of implementing dexosomes as therapeutic antitumor vaccines has been verified in two phase I and one phase II clinical trials in malignant melanoma and non small cell lung carcinoma patients. These studies proved the safety of dexosome administration and showed that dexosome vaccines have the capacity to trigger both the adaptive (T lymphocytes) and the innate (natural killer cells) immune cell recalls. In the current review, we will focus on the perspective of utilizing dexosome vaccines in the context of cancer immunotherapy.

Mesenchymal stem cell derived-exosomes: a modern approach in translational medicine.

Mesenchymal stem cells (MSCs) have captured great attention in regenerative medicine for over a few decades by virtue of their differentiation capacity, potent immunomodulatory properties, and their ability to be favorably cultured and manipulated. Recent investigations implied that the pleiotropic effects of MSCs is not associated to their ability of differentiation, but rather is mediated by the secretion of soluble paracrine factors. Exosomes, nanoscale extracellular vesicles, are one of these paracrine mediators. Exosomes transfer functional cargos like miRNA and mRNA molecules, peptides, proteins, cytokines and lipids from MSCs to the recipient cells. Exosomes participate in intercellular communication events and contribute to the healing of injured or diseased tissues and organs. Studies reported that exosomes alone are responsible for the therapeutic effects of MSCs in numerous experimental models. Therefore, MSC-derived exosomes can be manipulated and applied to establish a novel cell-free therapeutic approach for treatment of a variety of diseases including heart, kidney, liver, immune and neurological diseases, and cutaneous wound healing. In comparison with their donor cells, MSC-derived exosomes offer more stable entities and diminished safety risks regarding the administration of live cells, e.g. microvasculature occlusion risk. This review discusses the exosome isolation methods invented and utilized in the clinical setting thus far and presents a summary of current information on MSC exosomes in translational medicine.

Tailoring subtractive cell biopanning to identify diffuse gastric adenocarcinoma-associated antigens via human scFv antibodies.

Among various solid tumours, gastric cancer (GC) is one of the leading causes of cancer-related deaths worldwide. Expansion into the peritoneal cavity, which results from dissemination of diffuse cancer cells, is the main cause of mortality in gastric adenocarcinoma patients. Therefore, investigation of putative biomarkers involved in metastasis is prerequisite for GC management. In an effort to discover potential tumour markers associated with peritoneal metastasis of GC, a semi-synthetic human scFv library (Tomlinson I) was used to isolate novel antibody fragments recognizing MKN-45, a poorly differentiated diffuse gastric adenocarcinoma cell line. Four rounds of subtractive selection each consisting of extensive pre-absorption of phage library with NIH-3T3 murine embryonic fibroblasts and AGS (a well-differentiated intestinal gastric adenocarcinoma) cell line were carried out prior to positive selection on MKN-45 target cells. ELISA-based screening of 192 phage-displayed scFv clones indicated 21 high-affinity binders with specific staining of MKN-45 compared with AGS cells. Diversity analysis of the selected phage-scFvs resulted in five distinct sequences with multiple frequency. Further analysis by ELISA and flow cytometry verified three clones that specifically recognized MKN-45 cells. Liquid chromatography-mass spectrometry analysis of the scFv-immunoprecipitated proteins has led to identification of c-Met, HSP90 α and HSP90 ß as candidate biomarkers associated with diffuse GC. Immunohistochemistry revealed the capability of purified scFvs to differentiate diffuse and intestinal gastric adenocarcinoma. Taken together, the isolated MKN-45-specific scFv fragments and their cognate antigens would be beneficial in screening and management as well as targeting and therapy of the diffuse gastric adenocarcinoma.

---Successful Application of Whole Cell Panning for Isolation of Phage Antibody Fragments Specific to Differentiated Gastric Cancer Cells.

Purpose: Generation of antibodies which potentially discriminate between malignant and healthy cells is an important prerequisite for early diagnosis and treatment of gastric cancer (GC). Comparative analysis of cell surface protein landscape will provide an experimental basis for biomarker discovery, which is essential for targeted molecular therapies. This study aimed to isolate phage-displayed antibody fragments recognizing cell surface proteins, which were differently expressed between two closely related GC cell lines, namely AGS and MKN-45. Methods: We selected and screened a semisynthetic phage-scFv library on AGS, MKN-45, and NIH-3T3 cell lines by utilizing a tailored selection scheme that was designed to isolate phagescFvs that not only recognize the differentiated AGS cells but also distinguish them from NIH3T3 fibroblasts and the poorly differentiated MKN-45 cells. Results: After four rounds of subtractive whole cell panning, 14 unique clones were identified by ELISA screening and nucleotide sequencing. For further characterization, we focused on four phage-scFvs with strong signals in screening, and their specificity was confirmed by cell-based ELISA. Furthermore, the selected phage-scFvs were able to specifically stain AGS cells with 38.74% (H1), 11.04% (D11), 76.93% (G11), and 69.03% (D1) in flow cytometry analysis which supported the ability of these phage scFvs in distinguishing AGS from MKN-45 and NIH-3T3 cells. Conclusion: Combined with other proteomic techniques, these phage-scFvs can be applied to membrane proteome analysis and, subsequently, identification of novel tumor-related antigens mediating proliferation and differentiation of cells. Furthermore, such antibody fragments can be exploited for diagnostic purposes as well as targeted drug delivery of GC.