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Renal ischemia-reperfusion (I/R) can be precipitated by multiple clinical situations that lead to impaired renal function and associated mortality. The resulting tubular cell damage is the outcome of complex disorders including, an inflammatory process with an overproduction of cytokines. Here, diacerein (DIA), an inhibitor of proinflammatory cytokine interleukin-1 beta (IL-1β), was investigated against renal I/R in rats. DIA was orally administrated (50 mg/kg/day) for ten days before bilateral ischemia for 45 min with subsequent 2 hr. reperfusion. Interestingly, DIA alleviated the renal dysfunction and histopathological damage in the renal tissues. Pretreatment with DIA corrected the oxidative imbalance by prevented reduction in antioxidant levels of GSH and SOD, while it decreased the elevation of the oxidative marker, MDA. In addition, DIA downregulated IL-1β and TNF-α expression in the renal tissues. Consequent to inhibition of the oxidative stress and inflammatory cascades, DIA inhibited the phosphorylation of p38 mitogen-activated protein kinase (p38 MAPK). Therefore, downstream targets for p38 MAPK were also inhibited via DIA which prevented further increases of inflammatory cytokines and the apoptotic marker, caspase-3. Collectively, this study revealed the renoprotective role of DIA for renal I/R and highlighted the role of p38 MAPK encountered in its therapeutic application in renal disease., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Pulmonary fibrosis (PF) is the last phase of interstitial lung diseases (ILDs), which are a collection of pulmonary illnesses marked by parenchymal remodeling and scarring. Treatment can only halt the functional decline of the lung, raising the necessity of identifying the basic processes implicated in lung fibrogenesis. The Interferon lambda-3 ( IFNL3 ) gene variant, rs12979860, was determined to be related to an elevated risk of fibrosis in different organs, but the mechanism through which it mediates fibrogenesis is not clear. In the current research, we aim to figure out some of the mechanistic pathways by which IFN-λ3 mediates ILDs. 100 healthy controls and 74 ILD patients were genotyped for IFNL3 rs12979860. Then the mRNA expression of IFNL3 and some other proinflammatory mediators was examined according to genotype in the peripheral blood mononuclear cells (PBMCs) of ILDs patients. The IFNL3 rs12979860 genotype distribution of healthy individuals and ILDs patients was shown to be in Hardy-Weinberg equilibrium (HWE) with a minor allele frequency (MAF) of 0.293 and 0.326, respectively. Furthermore, the CC genotype was demonstrated to be linked to enhanced IFNL3 expression. Also, the CC genotype was linked to an increase in the mRNA expression of TLR4 ( P =  0.03) and the inflammatory cytokines IL-1β and TNF-α ( P =  0.01 and 0.04, respectively) and had no effect on the NF-kB level ( P =  0.3). From these results, we can deduce that IFN-λ3 may mediate tissue fibrosis via increasing the expression of IFN-λ3 itself and other proinflammatory mediators. This stimulates a self-sustaining loop mechanism which includes a reciprocal production of IFN-λ3, TLR4, IL-1β, and TNF-α leading to persistent inflammation and fibrosis., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

The breakdown of toll-like receptor (TLR) tolerance results in tissue damage, and hyperactivation of the TLRs and subsequent inflammatory consequences have been implicated as risk factors for more severe forms of disease and poor outcomes from various diseases including COVID-19 and metabolic (dysfunction) associated fatty liver disease (MAFLD). Here we provide evidence that membrane bound O-acyltransferase domain containing 7 (MBOAT7) is a negative regulator of TLR signalling. MBOAT7 deficiency in macrophages as observed in patients with MAFLD and in COVID-19, alters membrane phospholipid composition. We demonstrate that this is associated with a redistribution of arachidonic acid toward proinflammatory eicosanoids, induction of endoplasmic reticulum stress, mitochondrial dysfunction, and remodelling of the accessible inflammatory-related chromatin landscape culminating in macrophage inflammatory responses to TLRs. Activation of MBOAT7 reverses these effects. These outcomes are further modulated by the MBOAT7 rs8736 (T) MAFLD risk variant. Our findings suggest that MBOAT7 can potentially be explored as a therapeutic target for diseases associated with dysregulation of the TLR signalling cascade., (© 2022. The Author(s).)

Polycystic ovary syndrome (PCOS) is the most common gynaecological endocrine disease that causes anovulatory infertility. The current study aimed to explore the possible role of diacerein (DIA), an IL-1β inhibitor, in treating letrozole-induced PCOS in rats that exhibit the metabolic and endocrinal criteria of PCOS patients. PCOS was induced in female Wistar rats by the oral administration of letrozole (1 mg/kg, per orally, p.o.) for 21 days. Rats were then treated with DIA (25 mg/kg/day, p.o.), DIA (50 mg/kg/day, p.o.), or metformin (2 mg/100 g/day, p.o.) for 14 days after the PCOS induction. PCOS resulted in a significantly higher body weight, ovarian weight, ovarian size, and cysts, as well as an elevation in serum testosterone, LH, insulin, glycemia, and lipid profile levels. All of these effects were significantly reduced by the DIA administration. Additionally, DIA remarkably inhibited the letrozole-induced oxidative stress in the ovaries, muscles, and liver by reducing the upraised levels of malondialdehyde and total nitrite and increasing the suppressed levels of superoxide dismutase and catalase. DIA enhanced the protective proteins Keap-1, Nrf2, and OH-1 levels. Finally, DIA inhibited the elevated mRNA levels of NLRP3 and caspase-1, the up-regulated inflammatory cytokines IL-6, TNF-α, and the IL-1β/NFκB signaling pathway. Our results proved that DIA ameliorates letrozole-induced PCOS through its antioxidant and anti-inflammatory properties., (Copyright © 2022 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Despite the introduction of directly acting antivirals (DAAs), for the treatment of hepatitis C virus (HCV) infection, their cost, patient compliance, and viral resistance are still important issues to be considered. Here, we describe the generation of a novel JFH1-based HCV subgenomic replicon double reporter cell line suitable for testing different antiviral drugs and therapeutic interventions. This cells line allowed a rapid and accurate quantification of cell growth/viability and HCV RNA replication, thus discriminating specific from unspecific antiviral effects caused by DAAs or cytotoxic compounds, respectively. By correlating cell number and virus replication, we could confirm the inhibitory effect on the latter of cell over confluency and characterize an array of lentiviral vectors expressing single, double, or triple cassettes containing different combinations of short hairpin (sh)RNAs, targeting both highly conserved viral genome sequences and cellular factors crucial for HCV replication. While all vectors were effective in reducing HCV replication, the ones targeting viral sequences displayed a stronger antiviral effect, without significant cytopathic effects. Such combinatorial platforms as well as the developed double reporter cell line might find application both in setting-up anti-HCV gene therapy approaches and in studies aimed at further dissecting the viral biology/pathogenesis of infection.

We report the synthesis of new quinoline-2-one/pyrazole hybrids and their antiapoptotic activity. This effect was studied in sight of decreasing tissue damage induced by I/R in colon of rats using N-acetylcysteine (NAC) as anti-apoptotic reference. Compounds 6a, 6c and 6f showed significant improvement for oxidative stress parameters MDA, SOD, GSH and NOx in comparison with model group and greater than the reference NAC (N-acetylcysteine), whereas compounds 6d and 6e exhibited weaker antioxidant activity when compared with the reference NAC. Moreover, compounds 6a, 6c and 6f showed significant decrease in inflammatory mediators TNFα and CRB greater than NAC when compared to the model group especially compound 6c whose found CRB conc 1.90 (mg/dL) in comparison to NAC of conc 2.13 mg/dL. Additionally, colonic histopathological investigation was performed to all targeted compounds that indicates H&E sections of compounds 6a and 6f revealed apparent normal colonic cells while compound 6e showed dilated blood vessels with more apoptotic cells if compared with NAC. Caspase-3 inhibition assay revealed that compounds 6a, 6b and 6d weaken caspase-3 expression to an extent higher than NAC (1.063, 0.430, 0.731 and 1.115, respectively). Docking studies with caspase-3 revealed that most of the tested compounds showed good binding with the enzyme especially for compound 6d make several interactions better than that of the reference NAC., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Fibrosis across different organs and tissues is likely to share common pathophysiological mechanisms and pathways. Recently, a polymorphism (rs12979860) near the interferon lambda gene (IFNL3) was shown to be associated with fibrosis in liver across multiple disease etiologies. We determined whether this variant is a risk factor for pulmonary fibrosis (PF) and worsening cutaneous fibrosis in systemic sclerosis (SSc). Caucasian patients with SSc (n = 733) were genotyped to test for association with the presence of PF and worsening of skin fibrosis. Serum IFN-λ3 levels from 200 SSc cases were evaluated. An association of the IFNL3 polymorphism with PF was demonstrated (OR: 1.66 (95% CI: 1.142-2.416, p = 0.008). The IFNL3 variant was not a risk factor for worsening of skin fibrosis. Functionally, IFN-λ3 serum levels were higher among subjects with PF compared to those unaffected (P < 0.0001). In conclusion, IFNL3 serum levels and the genetic variant known to be associated with liver fibrosis are similarly linked to PF, but not to worsening of skin fibrosis in SSc. These data highlight both common fibrosis pathways operating between organs, as well as differential effects within the same disease.

Background & Aims: Irisin, the cleaved extra-cellular fragment of the Fibronectin type III domain-containing protein 5 (FNDC5) is a myokine that is proposed to have favorable metabolic activity. We aimed to elucidate the currently undefined role of variants in the FNDC5 gene in non-alcoholic fatty liver disease (NAFLD)., Methods: We prioritized single nucleotide polymorphisms in FNDC5 on the basis of their putative biological function and identified rs3480 in the 3' untranslated region (3'UTR). We studied the association of rs3480 with liver disease severity and the metabolic profile of 987 Caucasian patients with NAFLD. Functional investigations were undertaken using luciferase reporter assays of the 3'UTR of human FNDC5, pyrosequencing for allele-specific expression of FNDC5 in liver, measurement of serum irisin, and bioinformatics analysis., Results: The rs3480 (G) allele was associated with advanced steatosis (OR 1.29; 95% CI 1.08-1.55; p = 0.004), but not with other histological features. This effect was independent but additive to PNPLA3 and TM6SF2. The rs3480 polymorphism influenced FNDC5 mRNA stability and the binding of miR-135a-5P. Compared with controls, hepatic expression of this microRNA was upregulated while FNDC5 expression was downregulated. Elevated serum irisin was associated with reduced steatosis, and an improved metabolic profile., Conclusions: Carriage of the FNDC5 rs3480 minor (G) allele is associated with more severe steatosis in NAFLD through a microRNA-mediated mechanism controlling FNDC5 mRNA stability. Irisin is likely to have a favorable metabolic impact on NAFLD., Lay Summary: Irisin is a novel protein produced mainly by muscle, which is known to be released into the circulation, with an unclear role in liver fat deposition. This study demonstrates that genetic variants in the gene encoding the irisin protein modulate the risk of liver fat in patients with fatty liver disease. Interestingly, these effects are independent of, but additive to those of other recently described genetic variants that contribute to liver fat. In functional studies, we have deciphered the detailed molecular mechanisms by which this genetic variant mediates its effects., (Copyright © 2018 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Hepatocarcinogenesis is tightly linked to liver fibrosis. Recently, two GWAS variants, MICA rs2596542 and DEPDC5 rs1012068 were identified as being associated with the development of HCV-induced hepatocellular carcinoma (HCC) in Japanese patients. The role of these variants on hepatic inflammation and fibrosis that are closely associated with HCC development is not known, nor are the biological mechanisms underlying their impact on the liver. Here, we demonstrate in 1689 patients with chronic hepatitis C (CHC) (1,501 with CHC and 188 with HCV-related HCC), that the MICA (T) allele, despite not being associated with HCC susceptibility, is associated with increased fibrosis stage (OR: 1.47, 95% CI: 1.05-2.06, p = 0.02) and fibrosis progression rate (hazards ratio: 1.41, 95% CI: 1.04-1.90, p = 0.02). The DEPDC5 variant was not associated with any of these phenotypes. MICA expression was down-regulated in advanced fibrosis stages. Further, (T) allele carriage was associated with lower MICA expression in liver and serum. Transforming growth factor-β1 (TGF-β1) expression suppresses MICA expression in hepatic stellate cells. Our findings suggest a novel mechanism linking susceptibility to advanced fibrosis and subsequently indirectly to HCC, to the level of MICA expression through TGF-β1-dependent mechanisms.

Chronic hepatitis B (CHB) is characterized by hepatic inflammation that promotes progression to cirrhosis and predisposes to the development of hepatocellular carcinoma (HCC). Subtle interindividual genetic variation as well as viral and environmental factors interact to determine disease progression between individuals. Recently, the rs641738 membrane-bound O-acyltransferase domain-containing 7 (MBOAT7) polymorphism was demonstrated to influence histological liver damage in alcoholic liver disease, nonalcoholic fatty liver disease, and hepatitis C, but no data are available for CHB. We evaluated rs641738 influence on disease severity in a cohort of 1,101 patients with CHB. Forty-two patients underwent gene expression analysis to assess the functional consequences of rs641738 on hepatic MBOAT7 expression. The minor allele (T) of rs641738 was associated with greater inflammation (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.06-1.95; P = 0.001) and fibrosis (OR = 1.31; 95% CI, 1.19-1.92; P = 0.01). Risk allele frequency in whites (0.43) was greater than in Chinese (0.24), translating to a larger size effect in the former. The rs641738 (T) allele was associated with lower hepatic MBOAT7 expression (P = 0.008), and the latter was associated with serum liver enzymes and inflammation. Neither patatin-like phospholipase domain-containing protein 3 rs738409 nor transmembrane 6 superfamily member 2 rs58542926 polymorphisms influenced disease severity., Conclusion: In patients with CHB, MBOAT7 rs641738 influences hepatic inflammation and fibrosis stage. (Hepatology 2017;65:1840-1850)., (© 2017 by the American Association for the Study of Liver Diseases.)

Genetic variation in the IFNL3-IFNL4 (interferon-λ3-interferon-λ4) region is associated with hepatic inflammation and fibrosis. Whether IFN-λ3 or IFN-λ4 protein drives this association is not known. We demonstrate that hepatic inflammation, fibrosis stage, fibrosis progression rate, hepatic infiltration of immune cells, IFN-λ3 expression, and serum sCD163 levels (a marker of activated macrophages) are greater in individuals with the IFNL3-IFNL4 risk haplotype that does not produce IFN-λ4, but produces IFN-λ3. No difference in these features was observed according to genotype at rs117648444, which encodes a substitution at position 70 of the IFN-λ4 protein and reduces IFN-λ4 activity, or between patients encoding functionally defective IFN-λ4 (IFN-λ4-Ser70) and those encoding fully active IFN-λ4-Pro70. The two proposed functional variants (rs368234815 and rs4803217) were not superior to the discovery SNP rs12979860 with respect to liver inflammation or fibrosis phenotype. IFN-λ3 rather than IFN-λ4 likely mediates IFNL3-IFNL4 haplotype-dependent hepatic inflammation and fibrosis.

Cirrhosis likely shares common pathophysiological pathways despite arising from a variety of liver diseases. A recent GWAS identified rs641738, a polymorphism in the MBOAT7 locus, as being associated with the development of alcoholic cirrhosis. Here we explore the role of this variant on liver inflammation and fibrosis in two cohorts of patients with chronic hepatitis C. In 2,051 patients, rs641738 associated with severe hepatic inflammation and increased risk of fibrosis, as well as fast fibrosis progression. At functional level, rs641738 associated with MBOAT7 transcript and protein levels in liver and blood, and with serum inflammatory, oxidative stress and macrophage activation markers. MBOAT7 was expressed in immune cell subsets, implying a role in hepatic inflammation. We conclude that the MBOAT7 rs641738 polymorphism is a novel risk variant for liver inflammation in hepatitis C, and thereby for liver fibrosis.

Background & Aims: Peptide YY (PYY) and pancreatic polypeptide (PPY) are members of the neuropeptide Y peptide family. The neuropeptide Y receptor signaling pathway has been implicated in a number of physiologic processes, including the regulation of energy balance and bone mass. To investigate the contribution of endogenous PYY and PPY to these processes, we generated both Pyy- and Ppy-deficient mice., Methods: Pyy(-/-) and Ppy(-/-) mice and their respective wild-type littermates were studied from 8 weeks to 9 months of age. Food intake, metabolic parameters, and locomotor activity were monitored using indirect calorimetry. Body composition and bone parameters were analyzed using dual energy x-ray absorptiometry, histomorphometry, and vertebral compression testing., Results: Studies in these mice showed an osteopenic phenotype specific to the Pyy-deficient line, which included a reduction in trabecular bone mass and a functional deficit in bone strength. Furthermore, female Pyy(-/-) mice showed a greater sensitivity to ovariectomy-induced bone loss compared with wild-type littermates. No food intake or metabolic phenotype was apparent in male or female Pyy(-/-) mice on standard chow. However, female Pyy(-/-) mice on a high-fat diet showed a greater propensity to gain body weight and adiposity. No metabolic or osteopenic phenotype was observed in Ppy-deficient mice., Conclusions: These results indicate that endogenous PYY plays a critical role in regulating bone mass. In comparison, its role in regulating body weight is minor and is confined to situations of high-fat feeding.

Trb3, a mammalian homolog of Drosophila tribbles, was proposed as a suppressor of Akt activity, predominantly in conditions of fasting and diabetes. Given these prior studies, we sought to determine whether Trb3 plays a major role in modulating hepatic insulin sensitivity. To answer this question, we produced mice in which a lacZ reporter was knocked into the locus containing the gene Trib3, resulting in a Trib3 null animal. Trib3 expression analyses demonstrated that the Trib3 is expressed in liver, adipose tissues, heart, kidney, lung, skin, small intestine, stomach, and denervated, but not normal, skeletal muscle. Trib3(-/-) mice are essentially identical to their wild-type littermates in overall appearance and body composition. Phenotypic analysis of Trib3(-/-) mice did not detect any alteration in serum glucose, insulin, or lipid levels; glucose or insulin tolerance; or energy metabolism. Studies in Trib3(-/-) hepatocytes revealed normal Akt and glycogen synthase kinase- 3beta phosphorylation patterns, glycogen levels, and expressions of key regulatory gluconeogenic and glycolytic genes. These data demonstrate that deletion of Trib3 has minimal effect on insulin-induced Akt activation in hepatic tissue, and, as such, they question any nonredundant role for Trb3 in the maintenance of glucose and energy homeostasis in mice.

Ghrelin is a recently identified growth hormone (GH) secretogogue whose administration not only induces GH release but also stimulates food intake, increases adiposity, and reduces fat utilization in mice. The effect on food intake appears to be independent of GH release and instead due to direct activation of orexigenic neurons in the arcuate nucleus of the hypothalamus. The effects of ghrelin administration on food intake have led to the suggestion that inhibitors of endogenous ghrelin could be useful in curbing appetite and combating obesity. To further study the role of endogenous ghrelin in appetite and body weight regulation, we generated ghrelin-deficient (ghrl(-/-)) mice, in which the ghrelin gene was precisely replaced with a lacZ reporter gene. ghrl(-/-) mice were viable and exhibited normal growth rates as well as normal spontaneous food intake patterns, normal basal levels of hypothalamic orexigenic and anorexigenic neuropeptides, and no impairment of reflexive hyperphagia after fasting. These results indicate that endogenous ghrelin is not an essential regulator of food intake and has, at most, a redundant role in the regulation of appetite. However, analyses of ghrl(-/-) mice demonstrate that endogenous ghrelin plays a prominent role in determining the type of metabolic substrate (i.e., fat vs. carbohydrate) that is used for maintenance of energy balance, particularly under conditions of high fat intake.