NF-κB pathway affects silica nanoparticle-induced fibrosis via inhibited inflammatory response and epithelial-mesenchymal transition in 3D co-culture.

Long-term inhalation of silica nanoparticles (SiNPs) can induce pulmonary fibrosis (PF), nevertheless, the potential mechanisms remain elusive. Herein, we constructed a three-dimensional (3D) co-culture model by using Matrigel to investigate the interaction among different cells and potential regulatory mechanisms after SiNPs exposure. Methodologically, we dynamically observed the changes in cell morphology and migration after exposure to SiNPs by co-culturing mouse monocytic macrophages (RAW264.7), human non-small cell lung cancer cells (A549), and medical research council cell strain-5 (MRC-5) in Matrigel for 24 h. Subsequently, we detected the expression of nuclear factor kappa B (NF-κB), inflammatory factor and epithelial-mesenchymal transition (EMT) markers. The results showed that SiNPs produced toxic effects on cells. In the 3D co-culture state, the cell's movement velocity and displacement increased, and the cell migration ability was enhanced. Meanwhile, the expression of inflammatory factor tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) were upregulated, the epithelial marker E-cadherin (E-cad) was downregulated, the mesenchymal marker N-cadherin (N-cad) and myofibroblast marker alpha-smooth muscle actin (α-SMA) expression were upregulated, while NF-κB expression was also upregulated after SiNPs exposure. We further found that cells were more prone to transdifferentiate into myofibroblasts in the 3D co-culture state. Conversely, utilizing the NF-κB-specific inhibitor BAY 11-7082 effectively downregulated the expression of TNF-α, IL-6, interleukin-1ß (IL-1ß), N-cad, α-SMA, collagen-I (COL I), and fibronectin (FN), the expression of E-cad was upregulated. These findings suggest that NF-κB is involved in regulating SiNPs-induced inflammatory, EMT, and fibrosis in the 3D co-culture state.

Reconstruction of dermal layers evaluated by high-frequency ultrasound following treatment for skin fibrosis.

Background: Lymphedema is a chronic, progressive clinical condition that evolves with intense fibrosis, the most advanced stage of which is stage III (lymphostatic fibrosclerosis). Aim: The aim of the present study was to show the possibility to reconstruct the dermal layers with the intensive treatment of fibrosis using the Godoy method. Case description: A 55-year-old patient with an eight-year history of edema of the lower limb of the leg had constant episodes of erysipelas, despite regular treatments. The edema progressed continually, associated with a change in the color of the skin and the formation of a crust. Intensive treatment (eight hours per day for three weeks) was proposed with the Godoy method. The ultrasound was performed and results revealed substantial improvement in the skin, with the onset of the reconstruction of the dermal layers. Conclusion: It is possible to reconstruct the layers of the skin in fibrotic conditions caused by lymphedema.

Randomized, Controlled Trial of the FGF21 Analogue Pegozafermin in NASH.

BACKGROUND: Pegozafermin is a long-acting glycopegylated (pegylated with the use of site-specific glycosyltransferases) fibroblast growth factor 21 (FGF21) analogue in development for the treatment of nonalcoholic steatohepatitis (NASH) and severe hypertriglyceridemia. The efficacy and safety of pegozafermin in patients with biopsy-proven noncirrhotic NASH are not well established. METHODS: In this phase 2b, multicenter, double-blind, 24-week, randomized, placebo-controlled trial, we randomly assigned patients with biopsy-confirmed NASH and stage F2 or F3 (moderate or severe) fibrosis to receive subcutaneous pegozafermin at a dose of 15 mg or 30 mg weekly or 44 mg once every 2 weeks or placebo weekly or every 2 weeks. The two primary end points were an improvement in fibrosis (defined as reduction by ≥1 stage, on a scale from 0 to 4, with higher stages indicating greater severity), with no worsening of NASH, at 24 weeks and NASH resolution without worsening of fibrosis at 24 weeks. Safety was also assessed. RESULTS: Among the 222 patients who underwent randomization, 219 received pegozafermin or placebo. The percentage of patients who met the criteria for fibrosis improvement was 7% in the pooled placebo group, 22% in the 15-mg pegozafermin group (difference vs. placebo, 14 percentage points; 95% confidence interval [CI], -9 to 38), 26% in the 30-mg pegozafermin group (difference, 19 percentage points; 95% CI, 5 to 32; P = 0.009), and 27% in the 44-mg pegozafermin group (difference, 20 percentage points; 95% CI, 5 to 35; P = 0.008). The percentage of patients who met the criteria for NASH resolution was 2% in the placebo group, 37% in the 15-mg pegozafermin group (difference vs. placebo, 35 percentage points; 95% CI, 10 to 59), 23% in the 30-mg pegozafermin group (difference, 21 percentage points; 95% CI, 9 to 33), and 26% in the 44-mg pegozafermin group (difference, 24 percentage points; 95% CI, 10 to 37). The most common adverse events associated with pegozafermin therapy were nausea and diarrhea. CONCLUSIONS: In this phase 2b trial, treatment with pegozafermin led to improvements in fibrosis. These results support the advancement of pegozafermin into phase 3 development. (Funded by 89bio; ENLIVEN ClinicalTrials.gov number, NCT04929483.).

Reducing GEF-H1 Expression Inhibits Renal Cyst Formation, Inflammation, and Fibrosis via RhoA Signaling in Nephronophthisis.

Nephronophthisis (NPHP) is the most prevalent monogenic disease leading to end-stage renal failure in childhood. RhoA activation is involved in NPHP pathogenesis. This study explored the role of the RhoA activator guanine nucleotide exchange factor (GEF)-H1 in NPHP pathogenesis. We analyzed the expression and distribution of GEF-H1 in NPHP1 knockout (NPHP1KO) mice using Western blotting and immunofluorescence, followed by GEF-H1 knockdown. Immunofluorescence and renal histology were used to examine the cysts, inflammation, and fibrosis. A RhoA GTPase activation assay and Western blotting were used to detect the expression of downstream GTP-RhoA and p-MLC2, respectively. In NPHP1 knockdown (NPHP1KD) human kidney proximal tubular cells (HK2 cells), we detected the expressions of E-cadherin and α-smooth muscle actin (α-SMA). In vivo, increased expression and redistribution of GEF-H1, and higher levels of GTP-RhoA and p-MLC2 in renal tissue of NPHP1KO mice were observed, together with renal cysts, fibrosis, and inflammation. These changes were alleviated by GEF-H1 knockdown. In vitro, the expression of GEF-H1 and activation of RhoA were also increased, with increased expression of α-SMA and decreased E-cadherin. GEF-H1 knockdown reversed these changes in NPHP1KD HK2 cells. Thus, the GEF-H1/RhoA/MLC2 axis is activated in NPHP1 defects and may play a pivotal role in NPHP pathogenesis.

Hepatic fibrosis: Targeting peroxisome proliferator-activated receptor alpha from mechanism to medicines.

Liver fibrosis is the result of sustained chronic liver injury and inflammation leading to hepatocyte cell death followed by the formation of fibrous scars, which is the hallmark of NASH and alcoholic steatohepatitis and can lead to cirrhosis, HCC, and liver failure. Although progress has been made in understanding the pathogenesis and clinical consequences of hepatic fibrosis, therapeutic strategies for this disease are limited. Preclinical studies suggest that peroxisome proliferator-activated receptor alpha plays an important role in preventing the development of liver fibrosis by activating genes involved in detoxifying lipotoxicity and toxins, transrepressing genes involved in inflammation, and inhibiting activation of hepatic stellate cells. Given the robust preclinical data, several peroxisome proliferator-activated receptor alpha agonists have been tested in clinical trials for liver fibrosis. Here, we provide an update on recent progress in understanding the mechanisms by which peroxisome proliferator-activated receptor alpha prevents fibrosis and discuss the potential of targeting PPARα for the development of antifibrotic treatments.

Pathogenesis and treatment of non-alcoholic steatohepatitis and its fibrosis.

The initial presentation of non-alcoholic steatohepatitis (NASH) is hepatic steatosis. The dysfunction of lipid metabolism within hepatocytes caused by genetic factors, diet, and insulin resistance causes lipid accumulation. Lipotoxicity, oxidative stress, mitochondrial dysfunction, and endoplasmic reticulum stress would further contribute to hepatocyte injury and death, leading to inflammation and immune dysfunction in the liver. During the healing process, the accumulation of an excessive amount of fibrosis might occur while healing. During the development of NASH and liver fibrosis, the gut-liver axis, adipose-liver axis, and renin-angiotensin system (RAS) may be dysregulated and impaired. Translocation of bacteria or its end-products entering the liver could activate hepatocytes, Kupffer cells, and hepatic stellate cells, exacerbating hepatic steatosis, inflammation, and fibrosis. Bile acids regulate glucose and lipid metabolism through Farnesoid X receptors in the liver and intestine. Increased adipose tissue-derived non-esterified fatty acids would aggravate hepatic steatosis. Increased leptin also plays a role in hepatic fibrogenesis, and decreased adiponectin may contribute to hepatic insulin resistance. Moreover, dysregulation of peroxisome proliferator-activated receptors in the liver, adipose, and muscle tissues may impair lipid metabolism. In addition, the RAS may contribute to hepatic fatty acid metabolism, inflammation, and fibrosis. The treatment includes lifestyle modification, pharmacological therapy, and non-pharmacological therapy. Currently, weight reduction by lifestyle modification or surgery is the most effective therapy. However, vitamin E, pioglitazone, and obeticholic acid have also been suggested. In this review, we will introduce some new clinical trials and experimental therapies for the treatment of NASH and related fibrosis.

Cardiomyocyte-specific Peli1 contributes to the pressure overload-induced cardiac fibrosis through miR-494-3p-dependent exosomal communication.

Cardiac fibrosis is an essential pathological process in pressure overload (PO)-induced heart failure. Recently, myocyte-fibroblast communication is proven to be critical in heart failure, in which, pathological growth of cardiomyocytes (CMs) may promote fibrosis via miRNAs-containing exosomes (Exos). Peli1 regulates the activation of NF-κB and AP-1, which has been demonstrated to engage in miRNA transcription in cardiomyocytes. Therefore, we hypothesized that Peli1 in CMs regulates the activation of cardiac fibroblasts (CFs) through an exosomal miRNA-mediated paracrine mechanism, thereby promoting cardiac fibrosis. We found that CM-conditional deletion of Peli1 improved PO-induced cardiac fibrosis. Moreover, Exos from mechanical stretch (MS)-induced WT CMs (WT MS-Exos) promote activation of CFs, Peli1-/- MS-Exos reversed it. Furthermore, miRNA microarray and qPCR analysis showed that miR-494-3p was increased in WT MS-Exos while being down regulated in Peli1-/- MS-Exos. Mechanistically, Peli1 promoted miR-494-3p expression via NF-κB/AP-1 in CMs, and then miR-494-3p induced CFs activation by inhibiting PTEN and amplifying the phosphorylation of AKT, SMAD2/3, and ERK. Collectively, our study suggests that CMs Peli1 contributes to myocardial fibrosis via CMs-derived miR-494-3p-enriched exosomes under PO, and provides a potential exosomal miRNA-based therapy for cardiac fibrosis.

The Role of Tß4-POP-Ac-SDKP Axis in Organ Fibrosis.

Fibrosis is a pathological process in which parenchymal cells are necrotic and excess extracellular matrix (ECM) is accumulated due to dysregulation of tissue injury repair. Thymosin ß4 (Tß4) is a 43 amino acid multifunctional polypeptide that is involved in wound healing. Prolyl oligopeptidase (POP) is the main enzyme that hydrolyzes Tß4 to produce its derivative N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) which is found to play a role in the regulation of fibrosis. Accumulating evidence suggests that the Tß4-POP-Ac-SDKP axis widely exists in various tissues and organs including the liver, kidney, heart, and lung, and participates in the process of fibrogenesis. Herein, we aim to elucidate the role of Tß4-POP-Ac-SDKP axis in hepatic fibrosis, renal fibrosis, cardiac fibrosis, and pulmonary fibrosis, as well as the underlying mechanisms. Based on this, we attempted to provide novel therapeutic strategies for the regulation of tissue damage repair and anti-fibrosis therapy. The Tß4-POP-Ac-SDKP axis exerts protective effects against organ fibrosis. It is promising that appropriate dosing regimens that rely on this axis could serve as a new therapeutic strategy for alleviating organ fibrosis in the early and late stages.

circ_000166/miR-296 Aggravates the Process of Diabetic Renal Fibrosis by Regulating the SGLT2 Signaling Pathway in Renal Tubular Epithelial Cells.

Diabetic renal fibrosis is a common cause of end-stage renal disease, and the circRNA-miRNA-mRNA network may play an important role in the progression of diabetic nephropathy- (DN-) induced renal fibrosis. In this study, the role of circ_000166/miR-296/SGLT2 in the process of DN-related renal fibrosis was studied by constructing an animal model of DN renal fibrosis via lentiviral transfection, plasmid transfection, and dual-luciferase reporting techniques. Compared with that of normal controls, the expression of circ_000166 in the kidney tissues of DN renal fibrosis mice substantially increased. Silencing circ_000166 could minimize kidney damage and decrease urine protein levels, thereby inhibiting the progression of renal fibrosis. Moreover, circ_000166 could act as the ceRNA of miR-296 and competitively bind to miR-296, leading to an increase in the expression of the SGLT2 gene regulated by miR-296. Through mutual verification via in vivo and in vitro experiments, miR-296 was overexpressed and SGLT2 was silenced. Results showed that DN renal fibrosis and cell apoptosis were considerably reduced. We postulate that circ_000166/miR-296/SGLT2 may become a new target in the progression of DN renal fibrosis, and the regulation of this pathway may be a promising strategy for clinical treatment of DN renal fibrosis.

Twist1 regulates macrophage plasticity to promote renal fibrosis through galectin-3.

Renal interstitial fibrosis is the pathological basis of end-stage renal disease, in which the heterogeneity of macrophages in renal microenvironment plays an important role. However, the molecular mechanisms of macrophage plasticity during renal fibrosis progression remain unclear. In this study, we found for the first time that increased expression of Twist1 in macrophages was significantly associated with the severity of renal fibrosis in IgA nephropathy patients and mice with unilateral ureteral obstruction (UUO). Ablation of Twist1 in macrophages markedly alleviated renal tubular injury and renal fibrosis in UUO mice, accompanied by a lower extent of macrophage infiltration and M2 polarization in the kidney. The knockdown of Twist1 inhibited the chemotaxis and migration of macrophages, at least partially, through the CCL2/CCR2 axis. Twist1 downregulation inhibited M2 macrophage polarization and reduced the secretion of the profibrotic factors Arg-1, MR (CD206), IL-10, and TGF-ß. Galectin-3 was decreased in the macrophages of the conditional Twist1-deficient mice, and Twist1 was shown to directly activate galectin-3 transcription. Up-regulation of galectin-3 recovered Twist1-mediated M2 macrophage polarization. In conclusion, Twist1/galectin-3 signaling regulates macrophage plasticity (M2 phenotype) and promotes renal fibrosis. This study could suggest new strategies for delaying kidney fibrosis in patients with chronic kidney disease.

Imbalance in the estrogen/androgen ratio may affect prostate fibrosis through the TGF-ß/Smad signaling pathway.

OBJECTIVE: The present study aimed to investigate the effects of an imbalance in the estrogen/androgen ratio on prostate fibrosis. METHODS: Different concentrations of dihydrotestosterone (DHT) or estradiol (E2) dissolved in corn oil were injected subcutaneously into the nape of the castrated Sprague-Dawley (SD) rats over 28 consecutive days. Masson's trichrome staining and immunohistochemical staining were performed to detect the content of collagen fibers and the expression of collagen I, fibronectin, and elastin in the rat prostate of each group, respectively. DHT + E2 at different concentrations was administered to human normal prostate stromal immortalized cells (WPMY-1 cells) for 1 week. The expression of collagen I, fibronectin, elastin, transforming growth factor-ß1 (TGF-ß1), Smad3, and Smad7 was detected by Western blotting (WB). Then, WPMY-1 cells treated with 10 nM DHT + 5 pM E2 were incubated with the TGF-ß/Smad pathway inhibitor SD208 for 1 week, after which collagen I, fibronectin, and elastin expression was detected by WB. RESULTS: Compared with the uncastrated control and corn oil injection groups, the collagen fiber content and collagen I and fibronectin expression were increased and elastin expression was decreased in the castrated rat prostate with corn oil injection group (p < 0.01). Compared to castrated corn oil injection group, collagen fiber content, collagen I, and fibronectin expression were significantly decreased, and elastin expression was significantly increased in the castrated rat prostate 0.15 mg/kg DHT treatment group (p < 0.01). Following treatment with 0.15 mg/kg DHT, the content of collagen fibers, and the expression of collagen I and fibronectin were increased, and the expression of elastin was decreased in the rat prostate with increasing concentrations of E2 treatment group compared to the 0.15 mg/kg DHT group (p < 0.05, p < 0.01). Following treatment with 0.05 mg/kg E2, the collagen fiber content and the expression of collagen I and fibronectin were decreased, and the expression of elastin was increased in the rat prostate with increasing DHT concentration treatment group compared to the 0.05 mg/kg E2 group (p < 0.05, p < 0.01). Compared with the Control group, the expression of collagen I, fibronectin, TGF-ß1 and Smad3 was decreased, and the expression of elastin and Smad7 was increased in WPMY-1 cells after treatment with 10 nM DHT (p < 0.01). Following treatment with 10 nM DHT, the expression of collagen I, fibronectin, TGF-ß1, and Smad3 was increased, and the expression of elastin and Smad7 was decreased in WPMY-1 cells with increasing E2 concentration treatment compared to the 10 nM DHT group (p < 0.05, p < 0.01). Following treatment with 5 pM E2, the expression of collagen I, fibronectin, TGF-ß1, and Smad3 was decreased, and elastin and Smad7 expression was increased with increasing DHT concentration compared to the 5 pM E2 group (p < 0.05, p < 0.01). Compared to the 10 nM DHT + 5 pM E2 group, the expressions of collagen I and fibronectin were decreased; the expression of elastin was increased in WPMY-1 cells after the supplement of TGF-ß/Smad pathway inhibitor SD208 group (p < 0.05, p < 0.01). CONCLUSIONS: An imbalance in the estrogen/androgen ratio may affect prostate fibrosis. E2 may activate the degree of prostate fibrosis. In contrast to the effect of E2, DHT may inhibit the degree of prostate fibrosis, which might involve the TGF-ß/Smad signaling pathway.

Zyxin protects from hypertension-induced cardiac dysfunction.

Arterial hypertension causes left ventricular hypertrophy leading to dilated cardiomyopathy. Following compensatory cardiomyocyte hypertrophy, cardiac dysfunction develops due to loss of cardiomyocytes preceded or paralleled by cardiac fibrosis. Zyxin acts as a mechanotransducer in vascular cells that may promote cardiomyocyte survival. Here, we analyzed cardiac function during experimental hypertension in zyxin knockout (KO) mice. In zyxin KO mice, made hypertensive by way of deoxycorticosterone acetate (DOCA)-salt treatment telemetry recording showed an attenuated rise in systolic blood pressure. Echocardiography indicated a systolic dysfunction, and isolated working heart measurements showed a decrease in systolic elastance. Hearts from hypertensive zyxin KO mice revealed increased apoptosis, fibrosis and an upregulation of active focal adhesion kinase as well as of integrins α5 and ß1. Both interstitial and perivascular fibrosis were even more pronounced in zyxin KO mice exposed to angiotensin II instead of DOCA-salt. Stretched microvascular endothelial cells may release collagen 1α2 and TGF-ß, which is characteristic for the transition to an intermediate mesenchymal phenotype, and thus spur the transformation of cardiac fibroblasts to myofibroblasts resulting in excessive scar tissue formation in the heart of hypertensive zyxin KO mice. While zyxin KO mice per se do not reveal a cardiac phenotype, this is unmasked upon induction of hypertension and owing to enhanced cardiomyocyte apoptosis and excessive fibrosis causes cardiac dysfunction. Zyxin may thus be important for the maintenance of cardiac function in spite of hypertension.

Bone marrow-derived mesenchymal stem cells transplantation attenuates renal fibrosis following acute kidney injury by repairing the peritubular capillaries.

After the severe initial insults of acute kidney injury, progressive kidney tubulointerstitial fibrosis may occur, the peritubular capillary (PTC) rarefaction plays a key role in the disease progression. However, the mechanisms of PTC damage were not fully understood and potential therapeutic interventions were not explored. Previous studies of our research team and others in this field suggested that bone marrow-derived mesenchymal stem cells (BMSCs) transplanted into the AKI rat model may preserve the kidney function and pathological changes. In the current study, with the ischemia/reperfusion AKI rat model, we revealed that BMSCs transplantation attenuated the renal function decrease in the AKI model through preserving the peritubular capillaries (PTCs) function. The density of PTCs is maintained by BMSCs transplantation in the AKI model, detachment and relocation of pericytes in the PTCs diminished. Then we established that BMSCs transplantation may attenuate the renal fibrosis and preserve the kidney function after AKI by repairing the PTCs. Improving the vitality of pericytes, suppressing the detachment and trans-differentiation of pericytes, directly differentiation of BMSCs into pericytes by BMSCs transplantation all participate in the PTC repair. Through these processes, BMSCs rescued the microvascular damage and improved the density of PTCs. As a result, a preliminary conclusion can be reached that BMSCs transplantation can be an effective therapy for delaying renal fibrosis after AKI.

Late gadolinium enhancement-MRI determines definite lesion formation most accurately at 3 months post ablation compared to later time points.

AIMS: Neither the long-term development of ablation lesions nor the capability of late gadolinium enhancement (LGE)-MRI to detect ablation-induced fibrosis at late stages of scar formation have been defined. We sought to assess the development of atrial ablation lesions over time using LGE-MRI and invasive electroanatomical mapping (EAM). METHODS AND RESULTS: Ablation lesions and total atrial fibrosis were assessed in serial LGE-MRI scans 3 months and >12 months post pulmonary vein (PV) isolation. High-density EAM performed in subsequent repeat ablation procedures served as a reference. Serial LGE-MRI of 22 patients were analyzed retrospectively. The PV encircling ablation lines displayed an average LGE, indicative of ablation-induced fibrosis, of 91.7% ± 7.0% of the circumference at 3 months, but only 62.8% ± 25.0% at a median of 28 months post ablation (p < 0.0001). EAM performed in 18 patients undergoing a subsequent repeat procedure revealed that the consistent decrease in LGE over time was owed to a reduced detectability of ablation-induced fibrosis by LGE-MRI at time-points > 12 months post ablation. Accordingly, the agreement with EAM regarding detection of ablation-induced fibrosis and functional gaps was good for the LGE-MRI at 3 months (κ .74; p < .0001), but only weak for the LGE-MRI at 28 months post-ablation (κ .29; p < .0001). CONCLUSION: While non-invasive lesion assessment with LGE-MRI 3 months post ablation provides accurate guidance for future redo-procedures, detectability of atrial ablation lesions appears to decrease over time. Thus, it should be considered to perform LGE-MRI 3 months post-ablation rather than at later time-points > 12 months post ablation, like for example, prior to a planned redo-ablation procedure.

Novel pharmacological effects of lecithinized superoxide dismutase on ischemia/reperfusion injury in the kidneys of mice.

Renal ischemia/reperfusion (I/R) injury is a major clinical problem because it can cause acute kidney injury (AKI) or lead to the transition from AKI to chronic kidney disease (CKD). Oxidative stress, which involves the production of reactive oxygen species (ROS), plays an important role in the development and exacerbation of I/R-induced kidney injury. However, we have previously reported that lecithinized superoxide dismutase (PC-SOD), a SOD derivative with high tissue affinity and high stability in plasma, has beneficial effects in various disease models because of its inhibitory effect on ROS production. Therefore, we aimed to determine the effects of intravenous PC-SOD administration in a mouse model of renal injury induced by I/R. PC-SOD markedly ameliorated the I/R-induced increases in markers of renal damage (urea nitrogen, creatinine, neutrophil gelatinase-associated lipocalin, and interleukin-6) and tubular necrosis 48 h after the intervention. We also found that PC-SOD significantly ameliorated the I/R-induced increase in ROS production, using an ex vivo imaging system. Furthermore, PC-SOD inhibited the increases in expression of markers of fibrosis (α-smooth muscle actin and collagen 1A1) 96 h after, and renal fibrosis 25 days after I/R was induced. Finally, we found that PC-SOD ameliorated the I/R-induced AKI in mice with high-fat diet-induced prediabetes. These results suggest that PC-SOD inhibits AKI and the transition from AKI to CKD through the inhibition of ROS production. Therefore, we believe that PC-SOD may represent an effective therapeutic agent for I/R-induced renal injury.

Pirfenidone increases IL-10 and improves acute pancreatitis in multiple clinically relevant murine models.

Despite decades of research, there is no specific therapy for acute pancreatitis (AP). In the current study, we have evaluated the efficacy of pirfenidone, an antiinflammatory and antifibrotic agent that is approved by the FDA for treatment of idiopathic pulmonary fibrosis (IPF), in ameliorating local and systemic injury in AP. Our results suggest that treatment with pirfenidone in therapeutic settings (e.g., after initiation of injury), even when administered at the peak of injury, reduces severity of local and systemic injury and inflammation in multiple models of AP. In vitro evaluation suggests that pirfenidone decreases cytokine release from acini and macrophages and disrupts acinar-macrophage crosstalk. Therapeutic pirfenidone treatment increases IL-10 secretion from macrophages preceding changes in histology and modulates the immune phenotype of inflammatory cells with decreased levels of inflammatory cytokines. Antibody-mediated IL-10 depletion, use of IL-10-KO mice, and macrophage depletion experiments confirmed the role of IL-10 and macrophages in its mechanism of action, as pirfenidone was unable to reduce severity of AP in these scenarios. Since pirfenidone is FDA approved for IPF, a trial evaluating the efficacy of pirfenidone in patients with moderate to severe AP can be initiated expeditiously.

Pirfenidone and vitamin D mitigate renal fibrosis induced by doxorubicin in mice with Ehrlich solid tumor.

AIMS: Doxorubicin is a prominent anticancer agent. However, its organotoxic potential has restricted its clinical use. The current study was performed to investigate the protective effect of pirfenidone and vitamin D against doxorubicin-triggered nephrotoxicity. MATERIALS AND METHODS: Female albino mice (5 mice per group) were inoculated with Ehrlish scites carcinoma (EAC) cells for induction of solid tumor and treated with pirfenidone 500 mg/kg orally (p.o.) or vitamin D 0.5 µg/kg intraperitonially (i.p.), either individually or combined with single doxorubicin (15 mg/kg; i.p.) dose. Additionally, 5 mice were served as a normal group. Treatment commenced 7 days after inoculation of Ehrlich ascites carcinoma cells and lasted for 14 days. KEY FINDINGS: Pirfenidone and vitamin D enhanced the anti-tumor activity of doxorubicin, by decreasing tumor weight and volume. Doxorubicin increased kidney weights, creatinine, urea levels and collagen fibers deposition within renal tubules. Moreover, doxorubicin was associated with overexpression of nuclear factor-kappa B (NF-κB) and alpha-smooth muscle actin (α-SMA) as both parameters assessed by kidney immunohistochemistry. Furthermore, histological signs of large areas of interistital fibrosis and cellular infiltration were significant with sole doxorubicin treatment. Notably, doxorubicin elevated both MCP1 and TGFB1 gene expression in addition to increasing the protein expression of Smad3 and Jun N-terminal Kinase-1 (JNK1) while decreasing that of Smad7. Pirfenidone in combined with vitamin D abolished doxorubicin-evoked disturbances in the aforementioned parameters and blunted all histological alterations. SIGNIFICANCE: Pirfenidone and vitamin D demonstrated a viable approach to suppress the nephrotoxicity initiated by doxorubicin through inhibiting the JNK1 and MCP-1 pathways.

B10 cells decrease fibrosis progression following cardiac injury partially by IL-10 production and regulating hyaluronan secretion.

B10 cells play negative roles in inflammatory disorders by producing IL-10. However, their effects on fibrosis have not been elucidated. Therefore, this study was conducted to examine the dynamic changes of B10 cell frequency and their potential role in cardiac fibrosis. We found that the frequency of B10 cells was significantly increased, and they participated in the regression of fibrosis via IL-10, particularly by accelerating hyaluronan secretion and inhibiting collagen deposition. In vivo, hyaluronan ablation or treatment significantly restricted cardiac fibrosis development. hyaluronan-induced conversion of M1/M2 Mc was dependent on the size of hyaluronan. Low molecular weight hyaluronan promoted the conversion to M1 Mϕ, whereas medium and high molecular weight hyaluronan accelerated Mϕ transdifferentiation into the M2 phenotype. Adoptive transfer of B10 cells significantly attenuated collagen deposition whereas CD19-/- mice with reduced B10 cells exacerbated fibrosis following cardiac injury. Our results provide new evidence suggesting that B10 cells exert antifibrotic effects by regulating the extracellular matrix composition during cardiac injury, and also highlight that B10 cells may serve as a promising therapeutic candidate for managing cardiac fibrosis-associated disorders.

Calpain inhibition decreases myocardial fibrosis in chronically ischemic hypercholesterolemic swine.

OBJECTIVES: Calpain activation during ischemia is known to play critical roles in myocardial remodeling. We hypothesize that calpain inhibition (CI) may serve to reverse and/or prevent fibrosis in chronically ischemic myocardium. METHODS: Yorkshire swine were fed a high-cholesterol diet for 4 weeks followed by placement of an ameroid constrictor on the left circumflex artery to induce myocardial ischemia. 3 weeks later, animals received either: no drug; high-cholesterol control group (CON; n = 8); low-dose CI (0.12 mg/kg; LCI, n = 9); or high-dose CI (0.25 mg/kg; HCI, n = 8). The high-cholesterol diet and CI were continued for 5 weeks, after which myocardial tissue was harvested. Tissue samples were analyzed by western blot for changes in protein content. RESULTS: In the setting of hypercholesterolemia and chronic myocardial ischemia, CI decreased the expression of collagen in ischemic and nonischemic myocardial tissue. This reduced collagen content was associated with a corresponding decrease in Jak/STAT/MCP-1 signaling pathway, suggesting a role for Jak 2 signaling in calpain activity. CI also decreases the expression of focal adhesion proteins (vinculin) and stabilizes the expression of cytoskeletal and structural proteins (N-cadherin, α-fodrin, desmin, vimentin, filamin, troponin-I). CI had no significant effect on metabolic and hemodynamic parameters. CONCLUSIONS: Calpain inhibition may be a beneficial medical therapy to decrease collagen formation in patients with coronary artery disease and associated comorbidities.