Serum proteomic profiling of patients with compensated advanced chronic liver disease with and without clinically significant portal hypertension.

INTRODUCTION: Portal hypertension (PH) drives the progression of liver cirrhosis to decompensation and death. Hepatic venous pressure gradient (HVPG) measurement is the standard of PH quantification, and HVPG≥10 mmHg defines clinically significant PH (CSPH). We performed proteomics-based serum profiling to search for a proteomic signature of CSPH in patients with compensated advanced chronic liver disease (cACLD). MATERIALS AND METHODS: Consecutive patients with histologically confirmed cACLD and results of HVPG measurements were prospectively included. Serum samples were pooled according to the presence/absence of CSPH and analysed by liquid chromatography-mass spectrometry. Gene set enrichment analysis was performed, followed by comprehensive literature review for proteins identified with the most striking difference between the groups. RESULTS: We included 48 patients (30 with, and 18 without CSPH). Protein CD44, involved in the inflammatory response, vascular endothelial growth factor C (VEGF-C) and lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1), both involved in lymphangiogenesis were found solely in the CSPH group. Although identified in both groups, proteins involved in neutrophil extracellular traps (NET) formation, as well as tenascin C, autotaxin and nephronectin which mediate vascular contractility and lymphangiogenesis were more abundant in CSPH. DISCUSSION AND CONCLUSION: We propose that altered inflammatory response, including NET formation, vascular contractility and formation of new lymph vessels are key steps in PH development. Proteins such as CD44, VEGF-C, LYVE-1, tenascin C, Plasminogen activator inhibitor 1, Nephronectin, Bactericidal permeability-increasing protein, Autotaxin, Myeloperoxidase and a disintegrin and metalloproteinase with thrombospondin motifs-like protein 4 might be considered for further validation as potential therapeutic targets and candidate biomarkers of CSPH in cACLD.

In search of new stratification strategies: tissue proteomic profiling of papillary thyroid microcarcinoma in patients with localized disease and lateral neck metastases.

INTRODUCTION: Papillary thyroid carcinomas (PTC) are the most common thyroid malignancies that are often diagnosed as microcarcinomas when the tumor is less than one centimetre in diameter. Currently, there are no valid stratification strategies that would reliably assess the risk of lateral neck metastases and optimize surgical treatment. MATERIALS AND METHODS: Aiming to find potential tissue biomarkers of metastatic potential, we conducted a cross-sectional proteomic pilot study on formalin-fixed paraffin-embedded tissues of metastatic (N = 10) and non-metastatic (N = 10) papillary thyroid microcarcinoma patients. Samples were analysed individually using liquid chromatography/mass spectrometry, and the differentially expressed proteins (DEP) were functionally annotated. RESULTS: We identified five overexpressed DEPs in the metastatic group (EPB41L2, CSE1L, GLIPR2, FGA and FGG) with a known association to tumour biology. Using bioinformatic-based tools, we found markedly different profiles of significantly enriched biological processes between the two groups. CONCLUSIONS: The identified DEPs might have a role as potential tissue biomarkers for PTC metastases. However, further prospective research is needed to confirm our findings.

Stage II of Chronic Kidney Disease-A Tipping Point in Disease Progression?

Chronic kidney disease (CKD) is the progressive loss of renal function. Although advances have been made in understanding the progression of CKD, key molecular events in complex pathophysiological mechanisms that mark each stage of renal failure remain largely unknown. Changes in plasma protein profiles in different disease stages are important for identification of early diagnostic markers and potential therapeutic targets. The goal of this study was to determine the molecular profile of each CKD stage (from 1 to 5), aiming to specifically point out markedly expressed or downregulated proteins. We performed a cross-sectional shotgun-proteomic study of pooled plasma across CKD stages and compared them to healthy controls. After sample pooling and heparin-column purification we analysed proteomes from healthy to CKD stage 1 through 5 participants' plasma by liquid-chromatography/mass-spectrometry. We identified 453 proteins across all study groups. Our results indicate that key events, which may later affect the course of disease progression and the overall pathophysiological background, are most pronounced in CKD stage 2, with an emphasis on inflammation, lipoprotein metabolism, angiogenesis and tissue regeneration. We hypothesize that CKD stage 2 is the tipping point in disease progression and a suitable point in disease course for the development of therapeutic solutions.

ADAMTS-4 as a possible distinguishing indicator between osteoarthritis and haemophilic arthropathy.

INTRODUCTION: Osteoarthritis (OA) and haemophilic arthropathy (HA) are clinically similar, but pathologically distinct conditions which result in joint pain and loss of function. Distinguishing their disease mechanisms is therefore a key step in the development of curative therapy, as opposed to current symptomatic treatments. A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) 4 is a metzincin-family member proteoglycan with known local involvement in OA pathogenesis. AIM: To investigate the potential differences and discriminatory potential of ADAMTS-4 between OA and HA patients. METHODS: We determined ADAMTS-4 plasma concentrations by ELISA in patients with HA and OA. This pilot cross-sectional study included N = 40 male participants equally divided across four subgroups: haemophilia patients with severe or mild HA and control subjects with severe or mild/no OA. RESULTS: Our study showed a striking elevation in plasma ADAMTS-4 expression levels in HA patients as compared to OA, as well as an increase in patients with severe as compared to mild HA. By performing the binomial logistical analysis and fitting the receiver-operator curve (ROC) (cut-off probability .5), ADAMTS-4 had a sensitivity of 95% and specificity of 50% in discriminating between HA and OA among our study participants. CONCLUSION: Uncovering the marked differences in plasma levels of ADAMTS-4 in patients with HA versus OA potentially sheds new light on the mechanisms of HA pathogenesis and could foster more research into the roles ADAMTS-4 and other matrix metalloproteinases (MMPs) play in HA versus OA.

First Characterization of ADAMTS-4 in Kidney Tissue and Plasma of Patients with Chronic Kidney Disease-A Potential Novel Diagnostic Indicator.

Background: We have previously shown that metzincin protease ADAMTS-4 accompanies renal fibrogenesis, as it appears in the blood of hemodialysis patients. Methods: Native kidney (NKB) and kidney transplant (TXCI) biopsy samples as well as plasma from patients with various stages of CKD were compared to controls. In paired analysis, 15 TXCI samples were compared with their zero-time biopsies (TX0). Tissues were evaluated and scored (interstitial fibrosis and tubular atrophy (IFTA) for NKB and Banff ci for TXCI). Immunohistochemical (IHC) staining for ADAMTS-4 and BMP-1 was performed. Plasma ADAMTS-4 was detected using ELISA. Results: ADAMTS-4 IHC expression was significantly higher in interstitial compartment (INT) of NKB and TXCI group in peritubular capillaries (PTC) and interstitial stroma (INT). Patients with higher stages of interstitial fibrosis (ci > 1 and IFTA > 1) expressed ADAMTS-4 in INT more frequently in both groups (p = 0.005; p = 0.013; respectively). In paired comparison, TXCI samples expressed ADAMTS-4 in INT and PTC more often than TX0. ADAMTS-4 plasma concentration varied significantly across CKD stages, being highest in CKD 2 and 3 compared to other groups (p = 0.0064). Hemodialysis patients had higher concentrations of ADAMTS-4 compared to peritoneal dialysis (p < 0.00001). Conclusion: ADAMTS-4 might have a significant role in CKD as a potential novel diagnostic indicator.

Heterotopic ossification vs. fracture healing: Extracellular vesicle cargo proteins shed new light on bone formation.

Fibrodysplasia ossificans progressiva (FOP) is an extremely rare disease in which bone tissue forms in extraskeletal sites, which is known as heterotopic ossification (HO). Extracellular vesicles (EVs) are small phospholipid-enclosed particles released by various cells which have an emerging, but not completely understood role in various (patho)physiological processes. In order to further study the pathophysiology of FOP we conducted a small observational study comparing the proteomic profiles of EV cargo, derived from pooled plasma of four patient groups: FOP patient (N = 1) during active disease phase (flare-up), FOP patients during remission (N = 2), patients after long bone fracture (N = 20) and healthy controls (N = 10). After isolation of EVs - their protein cargo was determined using liquid chromatography / mass spectrometry, after which a functional gene enrichment analysis was performed. Our results show a sizeable difference of the proteomics profiles in which EVs from the bone fracture group show significant activity of integrin interactions, Wnt, VEGF, IGF-1 and PDGF pathways; conversely, FOP patients' EVs indicate that HO occurs via processes of innate immunity and the Ephrin B signaling pathway. We hypothesize that the Ephrin B signaling (expressed in EVs) contributes to HO by aiding in mesenchymal stem cell recruitment and osteogenic differentiation, as well as by contributing to the inflammatory response, including macrophage chemotaxis and activation. This is, to our knowledge, the first published analysis of EV protein cargo in FOP.

The Role of ADAMTS-4 in Atherosclerosis and Vessel Wall Abnormalities.

Extracellular matrix proteins are regulated by metzincin proteases, like the disintegrin metalloproteinases with thrombospondin motifs (ADAMTS) family members. This review focuses on the emerging role which ADAMTS-4 might play in vascular pathology, which has implications for atherosclerosis and vessel wall abnormalities, as well as for the resulting diseases, such as cardiovascular and cerebrovascular disease, aortic aneurysms, and dissections. Major substrates of ADAMTS-4 are proteoglycans expressed physiologically in smooth muscle cells of blood vessels. Good examples are versican and aggrecan, principal vessel wall proteoglycans that are targeted by ADAMTS-4, driving blood vessel atrophy, which is why this metzincin protease was implicated in the pathophysiology of vascular diseases with an atherosclerotic background. Despite emerging evidence, it is important not to exaggerate the role of ADAMTS-4 as it is likely only a small piece of the complex atherosclerosis puzzle and one that could be functionally redundant due to its high structural similarity to other ADAMTS family members. The therapeutic potential of inhibiting ADAMTS-4 to halt the progression of vascular disease after initialization of treatment is unlikely. However, it is not excluded that it might find a purpose as a biomarker of vascular disease, possibly as an indicator in a larger cytokine panel.

Post-COVID-19 exacerbation of fibrodysplasia ossificans progressiva with multiple flare-ups and extensive heterotopic ossification in a 45-year-old female patient.

Fibrodyplasia ossificans progressiva (FOP) is a rare hereditary disease, which has a variable course characterized by occasional flare-ups of heterotopic ossification (HO) in soft tissues that are followed by swelling, stiffness, pain and warmth. Here, we report for the first time a case of a 45-year-old female patient with known FOP recovering from COVID-19 with disease progression potentially linked with the viral illness. In December 2020 the patient contracted a mild form of COVID-19 infection without need for hospital admission. Since January 2021, the patient felt unwell, with occasional abdominal pain which progressively intensified. In March 2021 she presented with new onset of HO, complaining of pain, swelling and thickening sensation in the lower abdomen and left part of the neck. Computerized tomography (CT) and cytokine analysis were performed. CT scan revealed new heterotopic bone formation in multiple soft tissue areas of the neck indicating clear radiological progression. Radiotherapy, which has proven to be an efficient tool to control HO in this patient, was not able to halt HO formation after COVID-19 infection. Cytokine analysis of a plasma sample obtained during a flare-up after COVID-19 infection showed a significantly elevated pro-inflammatory cytokines compared to a flare-up panel prior to infection. Of the 23 analyzed levels of cytokines, a staggering number of 21 were above normal levels. This case is the first confirmation of uncontrolled post-COVID-19 effects in a FOP patient, which manifested with flare-ups followed by progressive HO, possibly caused by a thus far, never described form of post-COVID syndrome.

Systemic inhibition of BMP1-3 decreases progression of CCl4-induced liver fibrosis in rats.

Liver fibrosis is a progressive pathological process resulting in an accumulation of excess extracellular matrix proteins. We discovered that bone morphogenetic protein 1-3 (BMP1-3), an isoform of the metalloproteinase Bmp1 gene, circulates in the plasma of healthy volunteers and its neutralization decreases the progression of chronic kidney disease in 5/6 nephrectomized rats. Here, we investigated the potential role of BMP1-3 in a chronic liver disease. Rats with carbon tetrachloride (CCl4)-induced liver fibrosis were treated with monoclonal anti-BMP1-3 antibodies. Treatment with anti-BMP1-3 antibodies dose-dependently lowered the amount of collagen type I, downregulated the expression of Tgfb1, Itgb6, Col1a1, and Acta2 and upregulated the expression of Ctgf, Itgb1, and Dcn. Mehanistically, BMP1-3 inhibition decreased the plasma levels of transforming growth factor beta 1(TGFß1) by prevention of its activation and lowered the prodecorin production further suppressing the TGFß1 profibrotic effect. Our results suggest that BMP1-3 inhibitors have significant potential for decreasing the progression of fibrosis in liver cirrhosis.

In vitro cytotoxicity assessment of imidazolium ionic liquids: biological effects in fish Channel Catfish Ovary (CCO) cell line.

Increasing interest in the application of ionic liquids as green replacement for volatile organic solvents emphasized the need for the evaluation of their toxic effects at different biological systems in order to reduce the risk for human health and environment. To our knowledge, effects of imidazolium ionic liquids on cellular level of fish cell lines have not been studied yet. The cytotoxicity of imidazolium ionic liquids containing different anions and alkyl chain lengths as the substituent at the cation ring towards the fish CCO cell line was determined by WST-1 proliferation assay. Morphological alterations were examined by fluorescent microscopy using acridine orange/ethidium bromide staining and flow cytometry analysis was also performed. The results showed concentration-dependent cytotoxicity of ionic liquids in CCO cells, related to the type of anion and alkyl chain length, while EC50 values showed moderate to high cytotoxicity of tested imidazolium ionic liquids. Distinct morphological changes observed under fluorescence microscope and data obtained by flow cytometry suggest that the toxicity of imidazolium ionic liquids with longer alkyl chains could be related to necrosis. Results presented in here may be helpful for filling existing gaps of knowledge about ionic liquids toxicity and their impact on aquatic environment.