TGR5活性化はアナグリプチンによる糖尿病ラットに対する肝線維化抑制効果を増強する

Hyperglycemia and hyperinsulinemia activate the proliferative potential of hepatic stellate cells (HSCs) and promote hepatic fibrosis. Dipeptidyl peptidase-4 (DPP-4) inhibitors, antidiabetic agents, reportedly inhibit the HSC proliferation. Additionally, Takeda G protein-coupled receptor 5 (TGR5) agonists induce the systemic release of glucagon-like peptides from intestinal L cells, which maintains glycemic homeostasis. This study assessed the combined effect of TGR5 agonist and DPP-4 inhibitor on diabetes-based liver fibrosis development. Male diabetic rats received intraperitoneal injection of porcine serum (PS) to induce liver fibrosis, and they were orally administered the following agents: oleanolic acid (OA) as a TGR5 agonist, anagliptin (ANA) as a DPP-4 inhibitor, and a combination of both agents. Treatment with OA or ANA significantly improved glycemic status and attenuated intrahepatic steatosis and lipid peroxidation in diabetic rats. PS-induced liver fibrosis development was also drastically suppressed by treatment with either agent, and the combination of both reciprocally enhanced the antifibrotic effect. Fecal microbiome demonstrated that both agents inhibited the increase in the Firmicutes/Bacteroidetes ratio, an indicator of dysbiosis related to metabolic syndromes. Furthermore, ANA directly inhibited in vitro HSC proliferative and profibrogenic activities. Collectively, TGR5 agonist and DPP-4 inhibitor appears to be a novel strategy against liver fibrosis under diabetic conditions.博士（医学）・甲第766号・令和3年3月15日© 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)

胆汁酸吸着薬であるセベラマーは、内因性のリポポリサッカライドの過負荷を軽減して、非アルコール性脂肪性肝炎の肝線維化を改善する。

Despite the use of various pharmacotherapeutic strategies, fibrosis due to nonalcoholic steatohepatitis (NASH) remains an unsatisfied clinical issue. We investigated the effect of sevelamer, a hydrophilic bile acid sequestrant, on hepatic fibrosis in a murine NASH model. Male C57BL/6J mice were fed a choline-deficient, L-amino acid-defined, high-fat (CDHF) diet for 12 weeks with or without orally administered sevelamer hydrochloride (2% per diet weight). Histological and biochemical analyses revealed that sevelamer prevented hepatic steatosis, macrophage infiltration, and pericellular fibrosis in CDHF-fed mice. Sevelamer reduced the portal levels of total bile acid and inhibited both hepatic and intestinal farnesoid X receptor activation. Gut microbiome analysis demonstrated that sevelamer improved a lower α-diversity and prevented decreases in Lactobacillaceae and Clostridiaceae as well as increases in Desulfovibrionaceae and Enterobacteriaceae in the CDHF-fed mice. Additionally, sevelamer bound to lipopolysaccharide (LPS) in the intestinal lumen and promoted its fecal excretion. Consequently, the sevelamer treatment restored the tight intestinal junction proteins and reduced the portal LPS levels, leading to the suppression of hepatic toll-like receptor 4 signaling pathway. Furthermore, sevelamer inhibited the LPS-mediated induction of fibrogenic activity in human hepatic stellate cells in vitro. Collectively, sevelamer inhibited the development of murine steatohepatitis by reducing hepatic LPS overload.博士（医学）・甲第779号・令和3年3月15日© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)

ラットを用いた非アルコール生脂肪肝炎におけるアンジオテンシンⅡ受容体拮抗薬とリファキシミン併用薬投与による肝線維化抑制効果の検討

The progression of nonalcoholic steatohepatitis (NASH) is complicated. The multiple parallel-hits theory is advocated, which includes adipocytokines, insulin resistance, endotoxins, and oxidative stress. Pathways involving the gut-liver axis also mediate the progression of NASH. Angiotensin-II receptor blockers (ARB) suppress hepatic fibrosis via the activation of hepatic stellate cells (HSCs). Rifaximin, a nonabsorbable antibacterial agent, is used for the treatment of hepatic encephalopathy and has been recently reported to improve intestinal permeability. We examined the inhibitory effects on and mechanism of hepatic fibrogenesis by combining ARB and rifaximin administration. Fischer 344 rats were fed a choline-deficient/l-amino acid-defined (CDAA) diet for 8 weeks to generate the NASH model. The therapeutic effect of combining an ARB and rifaximin was evaluated along with hepatic fibrogenesis, the lipopolysaccharide-Toll-like receptor 4 (TLR4) regulatory cascade, and intestinal barrier function. ARBs had a potent inhibitory effect on hepatic fibrogenesis by suppressing HSC activation and hepatic expression of transforming growth factor-β and TLR4. Rifaximin reduced intestinal permeability by rescuing zonula occludens-1 (ZO-1) disruption induced by the CDAA diet and reduced portal endotoxin. Rifaximin directly affect to ZO-1 expression on intestinal epithelial cells. The combination of an ARB and rifaximin showed a stronger inhibitory effect compared to that conferred by a single agent. ARBs improve hepatic fibrosis by inhibiting HSCs, whereas rifaximin improves hepatic fibrosis by improving intestinal permeability through improving intestinal tight junction proteins (ZO-1). Therefore, the combination of ARBs and rifaximin may be a promising therapy for NASH fibrosis.博士（医学）・甲第780号・令和3年3月15日© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)

L-カルニチンとアンギオテンシン-II1型受容体遮断薬の組み合わせは、非アルコール性脂肪肝炎ラットモデルにおける肝線維症に有益な効果を有する

Inflammation and oxidative stress contribute to the progression of nonalcoholic steatohepatitis (NASH). Hepatic fibrosis and activated hepatic stellate cells (Ac-HSCs) are attenuated by Angiotensin-II type 1 Receptor Blocker (ARB), and L-carnitine is effective for NASH by ameliorating oxidative stress, but neither agent is effective in a clinical setting. We evaluated the effect of the combination of L-carnitine and ARB on liver fibrosis using a rat NASH model. A Choline-Deficient/L-Amino Acid-defined (CDAA) diet was fed to F344 rats for 8 weeks. The rats were then divided into a control group, group receiving L-carnitine or ARB alone, and group receiving L-carnitine plus ARB. Therapeutic efficacy was assessed by evaluating liver fibrosis, liver fatty acid metabolism, and oxidative stress. ARB inhibited liver-specific tumor necrotic factor-α and LPS-binding protein, which are involved in hepatic inflammation. L-Carnitine reduced hepatic oxidative stress by rescuing hepatic sterol-regulatory elementbinding protein 1 and thiobarbituric acid reactive substances induced by the CDAA diet. Combination of L-carnitine and ARB improved liver fibrosis, with concomitant HSC suppression. Therefore, we suggest that L-carnitine and ARB are effective in suppressing liver fibrosis. Currently both drugs are in clinical use, and a combination of the two could be an effective therapy for NASH fibrosis.博士（医学）・甲第736号・令和2年3月16日Copyright © 2019 Hideto Kawaratani, Biomed J Sci & Tech Res. This is an openaccess article distributed under the terms of the Commons Attribution 4.0 License (https://creativecommons.org/licenses/by/4.0/)

エスジーエルティー2阻害薬（カナグリフロジン）およびジペプチジルペプチダーゼ４阻害薬（テネリグリプチン）との併用療法は非糖尿病ラットモデルにおける非アルコール性脂肪肝炎の進行を抑制する

Hepatocellular carcinoma (HCC) is the strongest independent predictor of mortality in non-alcoholic steatohepatitis (NASH)-related cirrhosis. The effects and mechanisms of combination of sodium-dependent glucose cotransporter inhibitor and canagliflozin (CA) and dipeptidyl peptidase-4 inhibitor and teneligliptin (TE) on non-diabetic NASH progression were examined. CA and TE suppressed choline-deficient, L-amino acid-defined diet-induced hepatic fibrogenesis and carcinogenesis. CA alone or with TE significantly decreased proinflammatory cytokine expression. CA and TE significantly attenuated hepatic lipid peroxidation. In vitro studies showed that TE alone or with CA inhibited cell proliferation and TGF-β1 and α1 (I)-procollagen mRNA expression in Ac-HSCs. CA+TE inhibited liver fibrogenesis by attenuating hepatic lipid peroxidation and inflammation and by inhibiting Ac-HSC proliferation with concomitant attenuation of hepatic lipid peroxidation. Moreover, CA+TE suppressed in vivo angiogenesis and oxidative DNA damage. CA or CA+TE inhibited HCC cells and human umbilical vein endothelial cell (HUVEC) proliferation. CA+TE suppressed vascular endothelial growth factor expression and promoted increased E-cadherin expression in HUVECs. CA+TE potentially exerts synergistic effects on hepatocarcinogenesis prevention by suppressing HCC cell proliferation and angiogenesis and concomitantly reducing oxidative stress and by inhibiting angiogenesis with attenuation of oxidative stress. CA+TE showed chemopreventive effects on NASH progression compared with single agent in non-diabetic rat model of NASH, concurrent with Ac-HSC and HCC cell proliferation, angiogenesis oxidative stress, and inflammation. Both agents are widely, safely used in clinical practice; combined treatment may represent a potential strategy against NASH.博士（医学）・甲第765号・令和3年3月15日© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)

肝線維化に対するファルネソイドX受容体アゴニストとジペプチジルペプチダーゼ-4阻害薬の併用効果

Aim: Non-alcoholic steatohepatitis (NASH) has a broad clinicopathological spectrum (inflammation to severe fibrosis). The farnesoid X receptor agonist obeticholic acid (OCA) ameliorates the histological features of NASH; satisfactory antifibrotic effects have not yet been reported. Here, we investigated the combined effects of OCA + a dipeptidyl peptidase-4 inhibitor (sitagliptin) on hepatic fibrogenesis in a rat model of NASH. Methods: Fifty Fischer 344 rats were fed a choline-deficient L-amino-acid-defined (CDAA) diet for 12 weeks. The in vitro and in vivo effects of OCA + sitagliptin were assessed along with hepatic fibrogenesis, lipopolysaccharide-Toll-like receptor 4 (TLR4) regulatory cascade and intestinal barrier function. Direct inhibitory effects of OCA + sitagliptin on activated hepatic stellate cells (Ac-HSCs) were assessed in vitro. Results: Treatment with OCA + sitagliptin potentially inhibited hepatic fibrogenesis along with Ac-HSC proliferation and hepatic transforming growth factor (TGF)-β1, α1(I)-procollagen, and tissue inhibitor of metalloproteinase-1 (TIMP-1) mRNA expression and hydroxyproline levels. Obeticholic acid inhibited hepatic TLR4 expression and increased hepatic matrix metalloproteinase-2 expression. Obeticholic acid decreased intestinal permeability by ameliorating CDAA diet-induced zonula occludens-1 disruption, whereas sitagliptin directly inhibited Ac-HSC proliferation. The in vitro suppressive effects of OCA + sitagliptin on TGF-β1 and α1(I)-procollagen mRNA expression and p38 phosphorylation in Ac-HSCs were almost consistent. Sitagliptin directly inhibited the regulation of Ac-HSC. Conclusions: Treatment with OCA + sitagliptin synergistically affected hepatic fibrogenesis by counteracting endotoxemia induced by intestinal barrier dysfunction and suppressing Ac-HSC proliferation. Thus, OCA + sitagliptin could be a promising therapeutic strategy for NASH.博士（医学）・甲第737号・令和2年3月16日© 2019 The Japan Society of HepatologyThis is the peer reviewed version of the following article: [https://onlinelibrary.wiley.com/doi/full/10.1111/hepr.13385], which has been published in final form at [https://doi.org/10.1111/hepr.13385]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions

Efficacy and HCC development after DAA therapy for patients with chronic hepatitis C: a single center retrospective cohort study

Aim: The development of hepatocellular carcinoma (HCC) is reduced after interferon based treatment in patients with chronic hepatitis C (CHC). A new therapy using direct-acting antiviral agents (DAA) has been widely applied since 2014 for CHC. The purpose of this study is to investigate the efficacy, safety and development of HCC after DAA treatment.Methods: The authors enrolled 33 consecutive patients who were treated with DAA for CHC at the hospital between January 2015 and March 2016. The laboratory data were collected at the start and 24 weeks after DAA therapy.Results: The authors analyzed 33 patients (18 male, 15 female, mean age of 68-year-old). The hepatic C virus genotypes were type 1 (27 patients) and type 2 (6 patients). The number of patients treated with sofosbuvir (SOF) + ledipasvir, daclatasvir + asunaprevir and SOF + ribavirin was 14, 13 and 6, respectively. The sustained virological response (SVR24) rate was 100%. Aspartate aminotransferase, alanine aminotransferase and FIB4-index were significantly decreased after SVR24. Adverse effects were observed in 9 patients (anemia, 5; liver function test disorder, 2; sarcoidosis, 1; pruritus, 1). With regard to HCC development, one elderly patient (3.0%) had multiple HCC recurrence after SVR24.Conclusion: DAA therapy achieved a high SVR24 rate with a good serological response. However, one patient had multiple HCC recurrence. These findings indicate that careful follow-up may be essential after DAA therapy

TGR5 Activation Modulates an Inhibitory Effect on Liver Fibrosis Development Mediated by Anagliptin in Diabetic Rats

Hyperglycemia and hyperinsulinemia activate the proliferative potential of hepatic stellate cells (HSCs) and promote hepatic fibrosis. Dipeptidyl peptidase-4 (DPP-4) inhibitors, antidiabetic agents, reportedly inhibit the HSC proliferation. Additionally, Takeda G protein-coupled receptor 5 (TGR5) agonists induce the systemic release of glucagon-like peptides from intestinal L cells, which maintains glycemic homeostasis. This study assessed the combined effect of TGR5 agonist and DPP-4 inhibitor on diabetes-based liver fibrosis development. Male diabetic rats received intraperitoneal injection of porcine serum (PS) to induce liver fibrosis, and they were orally administered the following agents: oleanolic acid (OA) as a TGR5 agonist, anagliptin (ANA) as a DPP-4 inhibitor, and a combination of both agents. Treatment with OA or ANA significantly improved glycemic status and attenuated intrahepatic steatosis and lipid peroxidation in diabetic rats. PS-induced liver fibrosis development was also drastically suppressed by treatment with either agent, and the combination of both reciprocally enhanced the antifibrotic effect. Fecal microbiome demonstrated that both agents inhibited the increase in the Firmicutes/Bacteroidetes ratio, an indicator of dysbiosis related to metabolic syndromes. Furthermore, ANA directly inhibited in vitro HSC proliferative and profibrogenic activities. Collectively, TGR5 agonist and DPP-4 inhibitor appears to be a novel strategy against liver fibrosis under diabetic conditions

Association between Equol Production Status and Nonalcoholic Steatohepatitis

Equol is a metabolite of daidzein, a major soybean isoflavone with estrogenic and antioxidant activities. As the production of equol depends on the presence of certain members of the intestinal microflora, not all individuals can produce equol. We examined the relationship between NASH histological features and equol production. In an animal model, obese OLETF rats were intraperitoneally injected with a porcine serum to augment liver fibrogenesis. Equol-rich soy product, SE5-OH was orally administered during the experimental period. Treatment with SE5-OH markedly attenuated the development of liver fibrosis and expression of alpha-smooth muscle actin. In clinical research, 38 NAFLD patients (13 men and 25 women) were included. The degree of fibrosis and ballooning in equol-nonproducers was significantly higher than in equol-producers in women. The percentage of nonproducers with NAFLD activity score (NAS) ≥ 5 was significantly higher than that of producers. None of the histological features were significantly different between nonproducers and producers in men. Decision tree analysis identified predictors for NAS ≥ 5 in women. The status of equol production was the strongest predictor, followed by fasting glucose. Since equol can be noninvasively detected in urine, it can be applied as a screening tool for the progression of NASH in women

Association between Non-Alcoholic Fatty Liver Disease and Chronic Kidney Disease: A Cross-Sectional Study

It is unclear whether the link between non-alcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD) is mediated by common risk factors. We aimed to elucidate the association between NAFLD and CKD using propensity score (PS)-matched analysis. We assessed 3725 Japanese individuals, excluding those with hepatitis B or C infection and men and women who consumed >30 and >20 g/day of alcohol, respectively. Of these, we enrolled 1097 Japanese subjects with NAFLD diagnosed by ultrasonography and 1097 PS-matched subjects without NAFLD. The prevalence of CKD was higher in subjects with NAFLD than in those without NAFLD before PS matching, but there was no significant difference between these groups in terms of CKD prevalence after PS matching. There was no difference in the prevalence of CKD between those with and without NAFLD in the subgroup analyses. Logistic regression analysis demonstrated that obesity, hypertension, and hyperuricemia were independent predictors of CKD, but NAFLD was not independently associated with CKD. In subjects with NAFLD, obesity, hypertension, and hyperuricemia were independent predictors of CKD. Thus, the link between NAFLD and CKD may be mediated by common risk factors. We recommend screening for CKD when patients with NAFLD have the aforementioned comorbidities