Fibrotic Areas Research Articles

The Effect of Boric Acid and Sodium Pentaborate Pentahydrate-Treated Foreskin Derived Mesenchymal Stem Cells on Liver Fibrosis.

Liver fibrosis is a worldwide public health problem due to its life-threatening complications, including portal hypertension, liver failure, cirrhosis, and hepatocellular carcinoma (HCC). Liver fibrosis is the net result of a complex excessive accumulation of extracellular matrix (ECM). Activation of hepatic stellate cells (HSCs) are the cause of deposition of ECM and are commonly recognized as a key step in liver fibrosis. The aim of this study was to investigate the effect of foreskin-derived mesenchymal stem cells treated with boron compounds on liver fibrosis. Rats were injected intraperitoneally with thioacetamide (TAA) at a dose of 150mg/kg except sham and control groups' rats. Thioacetamide (TAA), foreskin-derived mesenchymal stem cells (TAA + FSDMSC), FSDMSC treated with boric acid (TAA + FSDMSC + BA), FSDMSC treated with sodium pentaborate pentahydrate (TAA + FSDMSC + NaB), control and sham groups were studied. Boron compound treated foreskin-derived mesenchymal stem cells were injected into the tail vein, and evaluations were conducted after 4weeks and liver tissues were obtained for structural, immunohistochemical, and western blot studies and blood samples were taken for biochemical analysis. FSDMSC (BA) alleviates TAA-induced rats liver fibrosis, and BA showed a positive effect on foreskin-derived mesenchymal stem cells viability. After using BA-treated mesenchymal stem cells, we observed that there was regression in the fibrotic areas at TAA-induced liver fibrosis. The result demonstrates that the contribution of TAA + FSDMSC and TAA + FSDMSC (NaB) at the level of structure is not effective in regression of fibrosis in TAA-generated liver fibrosis. We concluded that FSDMSC treated with BA may be a factor in the regression of fibrosis.

Delivery of nitric oxide with a pH-responsive nanocarrier for the treatment of renal fibrosis

Fibrosis is an excessive accumulation of extracellular matrix (ECM) that may cause severe organ dysfunction. Nitric oxide (NO), a multifunctional gaseous signaling molecule, may inhibit fibrosis, and delivery of NO may serve as a potential antifibrotic strategy. However, major limitations in the application of NO to treat fibrotic diseases include its nonspecificity, short half-life and low availability in fibrotic tissue. Herein, we aimed to develop a stimuli-responsive drug carrier to deliver NO to halt kidney fibrosis. We manufactured a nanoparticle (NP) composed of pH-sensitive poly[2-(diisopropylamino)ethyl methacrylate (PDPA) polymers to encapsulate a NO donor, a dinitrosyl iron complex (DNIC; [Fe2(μ-SEt)2(NO)4]). The NPs were stable at physiological pH7.4 but disintegrated at pH4.0-6.0. The NPs showed significant cytotoxicity to cultured human myofibroblasts and were able to inhibit the activation of myofibroblasts, as indicated by a lower expression level of α-smooth muscle actin and the synthesis of a major ECM component, collagen I, in cultured human myofibroblasts. When given to mice treated with unilateral ureteral ligation/obstruction (UUO) to induce kidney fibrosis, these NPs remained in blood at a stable concentration for as long as 24h and might enter the fibrotic kidneys to suppress myofibroblast activation and collagen I production, leading to a 70% reduction in the fibrotic area. In summary, our strategy to assemble a NO donor, the iron nitrosyl complex DNIC, into pH-responsive NPs proves effective in treating renal fibrosis and warrants further investigation for its therapeutic potential.

DOP07 Targeting the canonical WNT signalling pathway as a potential novel therapy in Crohn′s associated fibrosis

Abstract Background Crohn’s disease (CD) is characterized by chronic recurrent intestinal inflammation that leads to progressive fibrotic remodelling of the intestinal wall. Despite advances in medical therapy for CD, 50% of patients still require surgical treatment after 10 years of disease mainly due to fibrosis-associated intestinal stenosis formation. A specific anti-fibrotic therapy does not yet exist, underlining the medical need for further research in this area. The exact mechanism of fibrosis development in CD fibrosis is not yet understood, but WNT signalling has been shown to play a critical role in fibrosis in other organs. However, the role of WNT-signalling in intestinal fibrosis and its potential druggability is not well characterized. Methods Bulk RNA sequencing was performed to uncover important mechanistic pathways participating in fibrosis development in surgical specimens from patients with fibrostenosing CD. Non fibrotic non-inflamed areas of the same patients served as controls. To elucidate the functional role of matrix producing fibroblasts, primary cells were isolated from both areas. Their fibrotic potential was further characterized by flow cytometry, immunofluorescence, and RNA sequencing. Protein levels of fibrosis markers as well as WNT target genes were assessed using immunofluorescence imaging techniques. Results Gene set enrichment (GAGE) revealed highly upregulated WNT-pathway (p adj < 0.0029) in CD fibrosis compared to matched normal tissue. Flow cytometry revealed an increased population of PDPN+, PDGFRa+ mesenchymal cells in fibrotic segments compared to non-fibrotic tissue. These cells preserve their fibrotic phenotype in vitro showing elevated expression of aSMA and COL1 in FACS. Functional and gene analysis showed upregulated migratory potential of fibrotic fibroblasts, as well as matrix production capabilities (VIM, COL1A1, FN1). RNA sequencing of tissue as well as fibroblasts revealed markedly elevated expression the Wnt1 effector WISP1, which is upregulated in fibrotic cells and tissue. In turn, WISP1 treatment of primary fibroblasts led to activation of the canonical WNT pathway, its target transcription factors and genes (LEF1, MMP7). Conclusion Fibrosis formation in CD patients is associated with activated WNT signalling. One druggable protein, a downstream target gene of WNT-signalling could be WISP1. This will be further investigated in our in vitro as well as in our in vivo model, to propose a novel therapy for reducing surgical intervention in CD patients.

Novel small-molecule compound VCP979 attenuates renal fibrosis in male rats with unilateral ureteral obstruction.

Renal fibrosis is a hallmark of chronic kidney disease, while efficient therapy against renal fibrosis is still lacking. In this study, we investigated the role of a novel small-molecule compound VCP979 on renal fibrosis and inflammation in a rat model of unilateral ureteral obstruction (UUO). One week after the UUO surgery, rats were administered VCP979 by gavage for one week, and after treatment, magnetic resonance imaging of T1rho mapping and histopathological analysis were performed to evaluate renal fibrosis in vivo and ex vivo. This study showed that treatment with VCP979 effectively reduced renal fibrosis, extracellular matrix accumulation, and alleviated epithelial-mesenchymal transition in UUO rats, as well as improved renal function. In vivo T1rho mapping displayed increased T1rho values in the UUO rats, which was decreased after VCP979 treatment, and a positive correlation was detected between the T1rho values and the percentage of fibrotic area. Moreover, the administration of VCP979 also ameliorated the inflammatory cytokines expression and the infiltration of macrophages in renal tissues. Mechanistically, VCP979 treatment inhibited the activation of p38 mitogen-activated protein kinase, nuclear factor-kappa B, and transforming growth factor-β1/Smads signaling pathways. These results indicated that VCP979 could be an effective therapeutic agent for alleviating renal fibrosis and inflammation in the rat model of UUO via its antifibrotic and anti-inflammatory effects.

Critical Role of LMCD1 in Promoting Profibrotic Characteristics of Lung Myofibroblasts in Experimental and Scleroderma-Associated Lung Fibrosis.

Interstitial lung disease (ILD) is a serious complication and leading cause of mortality in patients with systemic sclerosis (SSc). In this study, we explored the role of LIM and cysteine-rich domains protein 1 (LMCD1) as a novel factor in the pathogenesis of SSc-related ILD (SSc-ILD). The expression and effects of LMCD1 were studied in lung tissue samples and fibroblasts from SSc-ILD patients and control subjects as well as in lung tissue samples from animal models. LMCD1 was consistently elevated in lung tissue samples and in fibroblasts isolated from SSc-ILD patients as compared to controls. Additionally, LMCD1 was found to be highly expressed in the lung in the fibroblast-specific protein (FSP)-driven, constitutively active transforming growth factor β receptor type I (TGFβR1) transgenic mouse model of ILD and the bleomycin-induced mouse model of ILD. In lung fibroblasts from SSc-ILD patients, LMCD1 is an essential factor for the TGFβ-induced generation of type I collagen, fibronectin, and α-smooth muscle actin (α-SMA). Depletion of LMCD1 by small interfering RNA reduced the expression of extracellular matrix proteins and lowered transcriptional activity and expression of α-SMA, as well as decreased the proliferation and contractile activity of SSc-ILD lung fibroblasts. In dense fibrotic areas of affected lung tissue, lung LMCD1 colocalized with α-SMA. In cultured scleroderma lung fibroblasts, LMCD1 colocalized and interacted with serum response factor which mediates LMCD1-induced contractile activity of lung fibroblasts. Our study identifies LMCD1 as a profibrotic molecule contributing to the activation of myofibroblasts and the persistent fibroproliferation observed in SSc-ILD. Thus, LMCD1 may be a potential novel therapeutic target for patients with SSc-ILD.

Uric acid promotes myocardial infarction injury via activating pyrin domain-containing 3 inflammasome and reactive oxygen species/transient receptor potential melastatin 2/Ca2+pathway

Cardiomyocytes injury has been considered as a key contributor for myocardial infarction (MI). Uric acid (UA) can induce cardiomyocytes injury, which is closely related to NLRP3 activation and inflammatory factor generation. However, the mechanism how UA modulates cardiomyocytes remains elusive. Western blotting and qRT-PCR were applied for measuring protein and mRNA expression, respectively. ROS production and Ca2+ influx were measured by flow cytometry. Patch clamp technique was used for measuring transient receptor potential melastatin 2 (TRPM2) channel. Ligation of left anterior descending for 2 h was performed to induce MI animal model. The rats were treated by different concentration of uric acid. The artery tissues were stained by HE and collected for measurement of NLRP3 and inflammatory factors. Supplementation of UA significantly promoted apoptosis, and augmented the expression of intercellular adhesion molecule-1, chemoattractant protein-1, vascular cell adhesion molecule-1, and NLRP3 inflammasome. Knockdown of NLRP3 reversed the influence of UA on MI by decreasing collagen deposition, fibrotic area, apoptosis. The expression of NLRP3 inflammasome increased markedly after treatment of UA. UA activated ROS/TRPM2/Ca2+ pathway through targeting NLRP3. UA activated NLRP3 inflammasome and augments inflammatory factor production, which in turn exacerbates cardiomyocytes injury. Knockdown of NLRP3 reversed the influence of UA on apoptosis and cell cycle. UA may promote cardiomyocytes injury through activating NLRP3 inflammasome and ROS/TRPM2 channel/Ca2+ pathway.

PS-B02-4: GLYCINE BETAINE ALLEVIATES MYOCARDIAL HYPERTROPHY IN SPONTANEOUS HYPERTENSION RATS BY REGULATING AMPK/NF-KAPPAB/STIM1/ORAI1 SIGNALING PATHWAY

Background: Spontaneous hypertension is one of the common cardiovascular diseases. Glycine betaine (GB) is a natural vitamin that has the potential to lower blood pressure. This work attempted to investigate the precise mechanism of action of GB in spontaneous hypertension. Methods: Spontaneous hypertension rats (SHRs) were administrated with 100, 200 or 400 mg/kg of GB by gavage, or followed by injection of lentivirus-mediated STIM1 overexpression vector. The heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart weight/body weight (HW/BW) of rats were monitored. The pathological changes of myocardium were examined by hematoxylin and eosin staining and Masson staining. The expression of gene and protein was detected by quantitative real-time PCR and western blotting. Results: GB at 200 and 400 mg/kg reduced the levels of HR, SBP, DBP and HW/BW in SHRs. GB decreased the cross-sectional area and fibrotic area in the myocardium, and down-regulated the expression of ANP and beta-MHC in the myocardium of SHRs. It indicated that GB treatment effectively alleviated myocardial hypertrophy in SHRs. Additionally, GB treatment enhanced p-AMPK expression and repressed the expression of p-NF-kappaB, STIM1 and Orai1 in the myocardium of SHRs. STIM1 overexpression reversed GB treatment-mediated inhibition of myocardial hypertrophy in SHRs. Conclusion: This study demonstrated that GB activated AMPK and repressed NF-kappaB/STIM1/Orai1 signaling pathway, which contributed to alleviate myocardial hypertrophy in SHRs. Thus, this work provides a theoretical basis for GB as an antihypertensive drug.

PS-B04-12: DEVELOPMENT OF VACCINE AGAINST CONNECTIVE TISSUE GROWTH FACTOR TO PREVENT THE PROGRESSION OF RENAL FIBROSIS

Objective: Hypertension is closely related with chronic kidney disease (CKD); Hypertension and CKD can cause and exacerbate each other, forming a vicious cycle. There is a critical need for efficient treatment of CKD. Renal fibrosis is a final common pathway to end-stage renal disease, and connective tissue growth factor (CTGF) is a well-recognized central profibrotic factor in fibrosis of various organ systems. Here, we developed a novel peptide vaccine against CTGF to prevent the progression of renal fibrosis. Design and method: Among sequences of CTGF, the sequence common to mice and humans in the interaction region with transforming growth factor-β; (TGF-β;) and bone morphogenic proteins was selected as the epitope for the vaccine. The efficacy of this vaccine was verified in two renal fibrosis models using male C57BL/6J mice: adenine-induced CKD and unilateral ureteral obstruction (UUO) models. Moreover, the functions of CTGF vaccine-elicited IgG antibodies were evaluated in an in vitro study. Results: Three immunizations with this CTGF vaccine at 2-week intervals elicited serum IgG antibodies specifically binding to human full-length CTGF, and the antigen-specific antibody titers were maintained at high level for > 30 weeks. In adenine-induced CKD model, histological analyses showed that immunization with the CTGF vaccine significantly attenuated renal interstitial fibrosis compared to the vehicle treatment (8.5 ± 0.8% vs 12.3 ± 0.8%; P < 0.01). The CTGF vaccination also suppressed the increased mRNA expressions of collagen 1α and α-smooth muscle actin (α-SMA) in kidney tissue samples. Moreover, vaccinated mice showed lower levels of serum urea nitrogen (UN) and creatinine and lower urine albumin-creatinine ratio compared with vehicle-treated mice (UN: 77.7 ± 5.0 vs 104.0 ± 6.8 mg/dL; P < 0.01. creatinine: 0.42 ± 0.02 vs 0.51 ± 0.04 mg/dL; P = 0.06. albumin-creatinine ratio: 74.7 ± 13.8 vs 132.0 ± 15.3 μg/mg; P < 0.05). In UUO model, the CTGF vaccination also ameliorated the expansion of the interstitial fibrotic areas (7.7 ± 0.4 vs 9.8 ± 0.7%; P < 0.05). In an in vitro study, CTGF vaccine-elicited IgG antibodies efficiently suppressed CTGF-induced- and TGF-β;-induced α-SMA expression in cultured kidney fibroblasts. Conclusions: The CTGF vaccine has the potential to prevent the progression of renal fibrosis and delay the deterioration of renal function with a low frequency of administration. Thus, this CTGF vaccine could be a promising preventive strategy for CKD patients.

АНТИФИБРОЗНЫЙ ЭФФЕКТ ПРОИЗВОДНЫХ ПИРИМИДИНА КСИМЕДОНА И ЕГО КОНЪЮГАТА С L-АСКОРБИНОВОЙ КИСЛОТОЙ

This article considers the antifibrotic properties of pyrimidine derivatives of the drug Xymedon (compound (I)) and its conjugate with L-ascorbic acid (compound (II)) in an experimental rat model of fibrosis with a preventive administration scheme. Experimental fibrosis was induced in Wistar rats given carbon tetrachloride (5% oil solution, 0.2 mL/kg orally twice a week) in combination with ethanol (5% solution in drinking water, free access) against compounds (I) and (II), both administered preventively. Fibrotic changes in the liver were detected by Van Gieson’s staining. The effects of the studied compounds on the liver and clinical condition of rats were evaluated through serum biochemical parameters. The treatment of rats with compounds (I) and (II) reduced the number of fibrotic areas threefold, ameliorated hepatic steatosis and necrosis as compared to the control group, and improved blood biochemical parameters (ALT, AST, and LDH). Interestingly, compound (II) had a more pronounced effect. Therefore, pyrimidine derivatives of Xymedon and its conjugate with L-ascorbic acid showed an antifibrotic effect in our experimental rat model of fibrosis.

PS-BPB10-5: POSSIBLE INVOLVEMENT OF RENAL TUBULAR NFAT5 IN AGING-ASSOCIATED RENAL DYSFUNCTION AND SALT-SENSITIVE HYPERTENSION

Objective: Japan is currently facing a super-aging society, where an incidence of lifestyle-related diseases has become a greater social burden. The number of patients with chronic kidney disease (CKD) and hypertension is being increased with age; however, it is not clearly defined why and how aging causes renal dysfunction and hypertension. Nuclear factor of activated T-cells 5 (NFAT5) is a transcription factor that is activated upon hypertonic conditions as observed in the renal medulla. We have shown that the renal tubular cell-specific NFAT5 conditional knockout (KO) mice exhibit salt-sensitive hypertension, while the mice exhibit impaired urine concentrating ability and are susceptible to renal fibrosis. These phenotypes resemble aging-associated renal dysfunction, i.e., urine concentrating disorder, salt-sensitive hypertension, and renal fibrosis. We therefore investigated the possible involvement of NFAT5 in aging-related changes of the kidney. Methods: Male wild-type (WT) and KO mice (12 weeks old) were subjected to unilateral ureteral obstruction (UUO) or sham operation. After 7 days, mice were sacrificed and kidneys were removed for analysis. Renal fibrosis was evaluated by AZAN staining. Senescence-associated beta-galactosidase (SA-β;-Gal) activity was examined by fluorescence study in the whole kidney slices. mRNA expression for senescence-associated secretory phenotype (SASP)-related factors (TGF-β;1, COL1A1, ICAM1, PAI-1, p21, p16, and p53) in the whole kidney tissue was examined by real-time PCR. Results: AZAN staining showed that UUO induced renal fibrosis both in WT and KO mice. The UUO-induced fibrotic area was significantly larger in KO mice than in WT mice in the medulla. In sham-operated mice, overall SA-β;-Gal activity was larger in KO mice, in which the activity was dominant in the corticomedullary region. In UUO groups, overall SA-β;-Gal activity was low compared to sham-operated groups. The mRNA expression of SASP-related factors was not different between WT and KO mice in sham-operated groups. UUO upregulated the mRNA expression of all SASP-related factors both in WT and KO mice. In UUO groups, the expression of TGF-β;1, COL1A1, ICAM1, and PAI-1 was significantly larger in KO mice than in WT mice. The expression of p21, p16, and p53 tended to be larger in KO mice than in WT mice. Conclusions: Renal tubular NFAT5 deficiency showed senescence-related phenotypes at baseline. Deficit of renal tubular NFAT5 may further induce cell senescence upon insult, which might accelerate aging-associated renal inflammation and dysfunction in CKD.

Relation of impulse oscillometry and spirometry with quantitative thorax computed tomography after COVID-19 pneumonia.

This study aimed to investigate if there is any correlation between the quantitative computed tomography and the impulse oscillometry or spirometry results of post-COVID-19 patients. The study comprised 47 post-COVID-19 patients who had spirometry, impulse oscillometry, and high-resolution computed tomography examinations at the same time. The study group consisted of 33 patients with quantitative computed tomography involvement, while the control group included 14 patients who did not have CT findings. The quantitative computed tomography technology was used to calculate percentages of density range volumes. The relationship between percentages of density range volumes for different quantitative computed tomography density ranges and impulse oscillometry-spirometry findings was statistically analyzed. In quantitative computed tomography, the percentage of relatively high-density lung parenchyma, including fibrotic areas, was 1.76±0.43 and 5.65±3.73 in the control and study groups, respectively. The percentages of primarily ground-glass parenchyma areas were found to be 7.60±2.86 and 29.25±16.50 in the control and study groups, respectively. In the correlation analysis, the forced vital capacity% predicted in the study group was correlated with DRV%[(-750)-(-500)] (volume of the lung parenchyma that has density between (-750)-(-500) Hounsfield units), but no correlation with DRV%[(-500)-0] was detected. Also, reactance area and resonant frequency were correlated with DRV%[(-750)-(-500)], while X5 was correlated with both DRV%[(-500)-0] and DRV%[(-750)-(-500)] density. Modified Medical Research Council score was correlated with predicted percentages of forced vital capacity and X5. After COVID-19, forced vital capacity, reactance area, resonant frequency, and X5 correlated with the percentages of density range volumes of ground-glass opacity areas in the quantitative computed tomography. X5 was the only parameter correlated with density ranges consistent with both ground-glass opacity and fibrosis. Furthermore, the percentages of forced vital capacity and X5 were shown to be associated with the perception of dyspnea.

Effects of Macrophage Polarization Induced by Mesoporous Silicon-Based Curcumin-siRNA Nanoparticles on the Proliferation of Tendon Stem Cells

Studies have shown that curcumin (CUR)-siRNA can improve excessive fibrosis in the repair of patellar tendon (PT) injury. First, mesoporous silicon nanoparticles (NPs) (MES-SiN) were prepared by a sol–gel method. The small molecule CUR was adsorbed in the internal pore canal of MES-Sin, and the cationic high molecular polyethyleneimine (PP) was adsorbed on the outer layer, which combined with negatively charged siRNA to form CUR@MES-SiN-PP/siRNA NPs. The preparation of NPs was observed by transmission electron microscopy (TEM). RAW264.7 macrophages were treated with different concentrations of NPs, and cell viability was determined by methyl tetrazolium (MTT) assay. The NPs were prepared by siRNA labeled with the fluorescent dye 6-carboxyfluorescein (FAM) and transfected into cells. The cellular uptake of the NPs was observed by confocal laser scanning microscopy (CLSM) and TEM. A total of 80 SPF SD rats (10 weeks of age) were randomly assigned into two groups to establish a PT injury model. The rats in experimental (Exp) group were injected with CUR@MES-SiN-PP/siRNA NP solution (2 μg/g) in the abdomen for 14 d, and those in control (Ctrl) group were injected with an equal dose of 1% dimethyl sulfoxide (DMSO). The rectus femoris of 24 rats were taken from each group 12 h and 1 d, 3 d, 5 d, 7 d, and 14 d after injury. Masson and hematoxylineosin were used to observe the degree of fibrosis of the PT tissue. The differentiation of macrophages was observed by flow cytometry, and the proliferation of tendon stem cells was observed by immunofluorescence approaches such as Pax7. The results suggested that CUR@MES-SiN-PP/siRNA NPs were successfully fabricated. The NPs showed dose-dependent cytotoxicity, the cell viability remained above 90% at concentrations below 10 μg/mL, and the NPs were ingested by higher cells. After injury, the fibrotic area of Exp group was drastically decreased (P <0.05), and the regenerated muscle fiber area was increased (P <0.05). The number of M2-type macrophages increased markedly 3 d, 5 d, 7 d, and 14 d after injury (P <0.05). Immunofluorescence showed that the proliferation of fluorescent cells 3 d after surgery was superior to that of Ctrl group (P <0.05).

Elevated fibrosis burden as assessed by MRI predicts cryoballoon ablation failure.

Late-gadolinium enhancement magnetic resonance (LGE-MRI) imaging is increasingly used in management of atrial fibrillation (AFib) patients. Here, we assess the usefulness of LGE-MRI-based fibrosis quantification to predict arrhythmia recurrence in patients undergoing cryoballoon ablation. Our secondary goal was to compare two widely used fibrosis quantification methods. In 102 AF patients undergoing LGE-MRI and cryoballoon ablation (mean age 62 years; 64% male; 59% paroxysmal AFib), atrial fibrosis was quantified using the pixel intensity histogram (PIH) and image intensity ratio (IIR) methods. PIH segmentations were completed by a third-party provider as part of the standard of care at our hospital; Image intensity ratio(IIR) segmentations of the same scans were carried out in our lab using a commercially available software package. Fibrosis burdens and spatial distributions for the two methods were compared. Patients were followed prospectively for recurrent arrhythmia following ablation. Average PIH fibrosis was 15.6 ± 5.8% of the left atrial (LA) volume. Depending on threshold (IIRthr ), the average IIR fibrosis (% of LA wall surface area) ranged from 5.0 ± 7.2% (IIRthr = 1.2) to 37.4 ± 10.9% (IIRthr = 0.97). An IIRthr of 1.03 demonstrated the greatest agreement between the methods, but spatial overlap of fibrotic areas delineated by the two methods was modest (Sorenson Dice coefficient: 0.49). Fourty-two patients (41.2%) had recurrent arrhythmia. PIH fibrosis successfully predicted recurrence (HR 1.07; p = .02) over a follow-up period of 362 ± 149 days; regardless of IIRthr , IIR fibrosis did not predict recurrence. PIH-based volumetric assessment of atrial fibrosis was modestly predictive of arrhythmia recurrence following cryoballoon ablation in this cohort. IIR-based fibrosis was not predictive of recurrence for any of the IIRthr values tested, and the overlap in designated areas of fibrosis between the PIH and IIR methods was modest. Caution must therefore be exercised when interpreting LA fibrosis from LGE-MRI, since the values and spatial pattern are methodology-dependent.

Oxidized-LDL Deteriorated the Renal Residual Function and Parenchyma in CKD Rat through Upregulating Epithelial Mesenchymal Transition and Extracellular Matrix-Mediated Tubulointerstitial Fibrosis-Pharmacomodulation of Rosuvastatin.

This study tested the hypothesis that intrarenal arterial transfusion of oxidized low-density lipoprotein (ox-LDL) jeopardized the residual renal function and kidney architecture in rat chronic kidney disease ((CKD), i.e., induced by 5/6 nephrectomy) that was reversed by rosuvastatin. Cell culture was categorized into A1 (NRK-52E cells), A2 (NRK-52E + TGF-β), A3 (NRK-52E + TGF-β + ox-LDL) and A4 (NRK-52E + TGF-β + ox-LD). The result of in vitro study showed that cell viability (at 24, 48 and 72 h), NRK-52E ox-LDL-uptake, protein expressions of epithelial-mesenchymal-transition (EMT) markers (i.e., p-Smad2/snail/α-SMA/FSP1) and cell migratory and wound healing capacities were significantly progressively increased from A1 to A4 (all p < 0.001). SD rats were categorized into group 1 (sham-operated control), group 2 (CKD), group 3 (CKD + ox-LDL/0.2 mg/rat at day 14 after CKD induction) and group 4 (CKD + ox-LDL-treated as group 3+ rosuvastatin/10 mg/kg/day by days 20 to 42 after CKD induction) and kidneys were harvested at day 42. The circulatory levels of BUN and creatinine, ratio of urine-protein to urine-creatinine and the protein expressions of the above-mentioned EMT, apoptotic (cleaved-caspase3/cleaved-PARP/mitochondrial-Bax) and oxidative-stress (NOX-1/NOX-2/oxidized-protein) markers were lowest in group 1, highest in group 3 and significantly higher in group 4 than in group 2 (all p < 0.0001). Histopathological findings demonstrated that the kidney injury score, fibrotic area and kidney injury molecule-1 (KIM-1) displayed an identical pattern, whereas the cellular expression of podocyte components (ZO-1/synaptopodin) exhibited an opposite pattern of EMT markers (all p < 0.0001). In conclusion, ox-LDL damaged the residual renal function and kidney ultrastructure in CKD mainly through augmenting oxidative stress, EMT and fibrosis that was remarkably reversed by rosuvastatin.

Matrix protein Tenascin-C promotes kidney fibrosis via STAT3 activation in response to tubular injury

Accumulating evidence indicates that the extracellular matrix (ECM) is not only a consequence of fibrosis, but also contributes to the progression of fibrosis, by creating a profibrotic microenvironment. Tenascin-C (TNC) is an ECM glycoprotein that contains multiple functional domains. We showed that following kidney injury, TNC was markedly induced in fibrotic areas in the kidney from both mouse models and humans with kidney diseases. Genetically deletion of TNC in mice significantly attenuated unilateral ureteral obstruction-induced kidney fibrosis. Further studies showed that TNC promoted the proliferation of kidney interstitial cells via STAT3 activation. TNC-expressing cells in fibrotic kidney were activated fibroblast 2 (Act.Fib2) subpopulation, according to a previously generated single nucleus RNA-seq dataset profiling kidney of mouse UUO model at day 14. To identify and characterize TNC-expressing cells, we generated a TNC-promoter-driven CreER2-IRES-eGFP knock-in mouse line and found that the TNC reporter eGFP was markedly induced in cells around injured tubules that had lost epithelial markers, suggesting TNC was induced in response to epithelium injury. Most of the eGFP-positive cells were both NG2 and PDGFRβ positive. These cells did not carry markers of progenitor cells or macrophages. In conclusion, this study provides strong evidence that matrix protein TNC contributes to kidney fibrosis. TNC pathway may serve as a potential therapeutic target for interstitial fibrosis and the progression of chronic kidney disease.

Age-dependent sex difference of non-alcoholic fatty liver disease in TSOD and db/db mice.

According to previous clinical studies, the prevalence of non-alcoholic fatty liver disease (NAFLD) is higher in men than women only during the reproductive age. Animal models of NAFLD that reflect sex differences in humans have not been established. In this study, we examined sex differences in the hepatic lesions of Tsumura Suzuki obese diabetes (TSOD) and db/db mice, which are representative genetic models of NAFLD. Male and female TSOD and db/db mice were fed with a normal diet and tap water ad libitum. Six male and female mice of each strain were sacrificed at the ages of 3 and 9 months, respectively, and serum biochemical, pathological, and molecular analyses were performed. Serum aspartate aminotransferase (AST) levels were significantly higher in male than female mice of both strains at the age of 3 months; however, at 9 months, significant sex differences were not observed. Similarly, alanine aminotransferase (ALT) levels were significantly higher in male mice than in female TSOD mice at the age of 3 months; however, at 9 months, significant sex differences were not observed. Image analysis of histological slides revealed that the frequency of the steatotic area was significantly higher in male than female db/db mice at the age of 3 months; however, significant sex differences were not observed at 9 months. The frequency of Sirius red-positive fibrotic area was significantly higher in male than female mice in both strains at the age of 3 months; however, significant sex differences were not observed at 9 months. Serum AST and ALT levels and hepatic steatosis and fibrosis in TSOD and db/db mice showed age-dependent sex differences consistent with those observed in human NAFLD. These mice may be suitable for studying sex differences of the disease.

Novel Cardiokine GDF3 Predicts Adverse Fibrotic Remodeling After Myocardial Infarction.

Myocardial infarction (MI) induces a repair response that ultimately generates a stable fibrotic scar. Although the scar prevents cardiac rupture, an excessive profibrotic response impairs optimal recovery by promoting the development of noncontractile fibrotic areas. The mechanisms that lead to cardiac fibrosis are diverse and incompletely characterized. We explored whether the expansion of cardiac fibroblasts after MI can be regulated through a paracrine action of cardiac stromal cells. We performed a bioinformatic secretome analysis of cardiac stromal PW1+ cells isolated from normal and post-MI mouse hearts to identify novel secreted proteins. Functional assays were used to screen secreted proteins that promote fibroblast proliferation. The expressions of candidates were subsequently analyzed in mouse and human hearts and plasmas. The relationship between levels of circulating protein candidates and adverse post-MI cardiac remodeling was examined in a cohort of 80 patients with a first ST-segment-elevation MI and serial cardiac magnetic resonance imaging evaluations. Cardiac stromal PW1+ cells undergo a change in paracrine behavior after MI, and the conditioned media from these cells induced a significant increase in the proliferation of fibroblasts. We identified a total of 12 candidates as secreted proteins overexpressed by cardiac PW1+ cells after MI. Among these factors, GDF3 (growth differentiation factor 3), a member of the TGF-β (transforming growth factor-β) family, was markedly upregulated in the ischemic hearts. Conditioned media specifically enriched with GDF3 induced fibroblast proliferation at a high level by stimulation of activin-receptor-like kinases. In line with the secretory nature of this protein, we next found that GDF3 can be detected in mice and human plasma samples, with a significant increase in the days after MI. In humans, higher GDF3 circulating levels (measured in the plasma at day 4 after MI) were significantly associated with an increased risk of adverse remodeling 6 months after MI (adjusted odds ratio, 1.76 [1.03-3.00]; P=0.037), including lower left ventricular ejection fraction and a higher proportion of akinetic segments. Our findings define a mechanism for the profibrotic action of cardiac stromal cells through secreted cardiokines, such as GDF3, a candidate marker of adverse fibrotic remodeling after MI. URL: https://www. gov; Unique identifier: NCT01113268.

Localization of natriuretic peptide receptors A, B, and C in healthy and diseased mouse kidneys

The natriuretic peptides (NPs) ANP (atrial natriuretic peptide) and BNP (B-type natriuretic peptide) mediate their widespread effects by activating the natriuretic peptide receptor-A (NPR-A), while C-type natriuretic peptide (CNP) acts via natriuretic peptide receptor-B (NPR-B). NPs are removed from the circulation by internalization via the natriuretic peptide clearance receptor natriuretic peptide receptor-C (NPR-C). In addition to their well-known functions, for instance on blood pressure, all three NPs confer significant cardioprotection and renoprotection. Since neither the NP-mediated renal functions nor the renal target cells of renoprotection are completely understood, we performed systematic localization studies of NP receptors using in situ hybridization (RNAscope) in mouse kidneys. NPR-A mRNA is highly expressed in glomeruli (mainly podocytes), renal arterioles, endothelial cells of peritubular capillaries, and PDGFR-receptor β positive (PDGFR-β) interstitial cells. No NPR-A mRNA was detected by RNAscope in the tubular system. In contrast, NPR-B expression is highest in proximal tubules. NPR-C is located in glomeruli (mainly podocytes), in endothelial cells and PDGFR-β positive cells. To test for a possible regulation of NPRs in kidney diseases, their distribution was studied in adenine nephropathy. Signal intensity of NPR-A and NPR-B mRNA was reduced while their spatial distribution was unaltered compared with healthy kidneys. In contrast, NPR-C mRNA signal was markedly enhanced in cell clusters of myofibroblasts in fibrotic areas of adenine kidneys. In conclusion, the primary renal targets of ANP and BNP are glomerular, vascular, and interstitial cells but not the tubular compartment, while the CNP receptor NPR-B is highly expressed in proximal tubules. Further studies are needed to clarify the function and interplay of this specific receptor expression pattern.

Diagnostic accuracy of ultrasound-based multimodal radiomics modeling for fibrosis detection in chronic kidney disease

ObjectivesTo predict kidney fibrosis in patients with chronic kidney disease using radiomics of two-dimensional ultrasound (B-mode) and Sound Touch Elastography (STE) images in combination with clinical features.MethodsThe Mindray Resona 7 ultrasonic diagnostic apparatus with SC5-1U convex array probe (bandwidth frequency of 1–5 MHz) was used to perform two-dimensional ultrasound and STE software. The severity of cortical tubulointerstitial fibrosis was divided into three grades: mild interstitial fibrosis and tubular atrophy (IFTA), fibrotic area < 25%; moderate IFTA, fibrotic area 26–50%; and severe IFTA, fibrotic area > 50%. After extracting radiomics from B-mode and STE images in these patients, we analyzed two classification schemes: mild versus moderate-to-severe IFTA, and mild-to-moderate versus severe IFTA. A nomogram was constructed based on multiple logistic regression analyses, combining clinical and radiomics. The performance of the nomogram for differentiation was evaluated using receiver operating characteristic (ROC), calibration, and decision curves.ResultsA total of 150 patients undergoing kidney biopsy were enrolled (mild IFTA: n = 74; moderate IFTA: n = 33; severe IFTA: n = 43) and randomized into training (n = 105) and validation cohorts (n = 45). To differentiate between mild and moderate-to-severe IFTA, a nomogram incorporating STE radiomics, albumin, and estimated glomerular filtration (eGFR) rate achieved an area under the ROC curve (AUC) of 0.91 (95% confidence interval [CI]: 0.85–0.97) and 0.85 (95% CI: 0.77–0.98) in the training and validation cohorts, respectively. Between mild-to-moderate and severe IFTA, the nomogram incorporating B-mode and STE radiomics features, age, and eGFR achieved an AUC of 0.93 (95% CI: 0.89–0.98) and 0.83 (95% CI: 0.70–0.95) in the training and validation cohorts, respectively. Finally, we performed a decision curve analysis and found that the nomogram using both radiomics and clinical features exhibited better predictability than any other model (DeLong test, p < 0.05 for the training and validation cohorts).ConclusionA nomogram based on two-dimensional ultrasound and STE radiomics and clinical features served as a non-invasive tool capable of differentiating kidney fibrosis of different severities.Key Points• Radiomics calculated based on the ultrasound imaging may be used to predict the severities of kidney fibrosis.• Radiomics may be used to identify clinical features associated with the progression of tubulointerstitial fibrosis in patients with CKD.• Non-invasive ultrasound imaging-based radiomics method with accuracy aids in detecting renal fibrosis with different IFTA severities.

Antemortem‐postmortem correlates of 4D‐Flow MRI in cerebral vessels

AbstractBackgroundCerebrovascular disease (CVD) is associated with increased dementia risk and often co‐occurs with Alzheimer’s disease (AD). Non‐invasive quantitative 4D‐Flow MRI can be used to characterize cerebrovascular hemodynamics and study CVD/AD interactions during life, but has not been validated against postmortem pathological assessment. This study compares antemortem 4D‐Flow metrics with postmortem pathological assessment in cerebral arteries to inform the interpretation of 4D‐Flow MRI.MethodsThree participants from the Wisconsin ADRC underwent antemortem 4D‐Flow and postmortem pathological examination. Subjects had MCI or dementia before death with suspected AD etiology (Table 1). Antemortem 4D‐Flow was acquired on a 3.0T system (GE Healthcare). Vessel cross‐sections from 4D‐Flow angiograms of cerebral arteries were used to estimate blood flow, pulsatility index (PI), and luminal area. Upon death, brain extraction and neuropathological examination were performed according to NIA‐AA guidelines. Sampled cerebral arteries included left anterior (A1) and middle (M1) cerebral, and left internal carotid arteries, basilar artery, and left and right posterior cerebral (P1 and P2) and vertebral arteries. Mason’s trichrome stained sections of the arteries were captured using an Aperio Digital Slide Scanner. QuPath software was used to delineate the intima, media and functional luminal area of the vessels. A pixel classifier measured the area of smooth muscle cells (SMC) and fibrous tissue (Figure 1). The percentage of stenosis (%stenosis) was calculated as the area of atherosclerotic plaque divided by the area encompassed by the elastica. The percentage of media fibrosis (%fibrosis) was calculated as the area of fibrotic tissue divided by the sum of the SMC and fibrotic areas within the media. Spearman correlations were used to compare antemortem and postmortem vascular measures without correction for multiple comparisons.ResultsImaging‐postmortem correlates were highest for PI vs. %fibrosis (ρSpearman=0.42), mean flow vs. %stenosis (ρSpearman=0.40), and comparisons of luminal area (ρSpearman=0.43) (Table 2, Figure 2). Correlations between other imaging and pathology measures were low (|ρSpearman|&lt;0.21).ConclusionThese data provide preliminary evidence that 4D‐Flow metrics correlate with underlying arterial vessel stenosis and fibrosis. Future work is ongoing to investigate antemortem‐postmortem associations in more cases.