Complementary role of peripheral and central autonomic nervous system on insulin-like growth factor-1 activation to prevent fatty liver disease.

BACKGROUND: Insulin-like growth factor-1 (IGF-1) is involved in the pathology of non-alcoholic fatty liver disease (NAFLD) and ameliorates fatty infiltration in the liver. It is activated by growth hormone (GH); however, the role of GH-IGF-1 axis in NAFLD developmental phase has not been well identified. Therefore, in this study, we focused on the effect of IGF-1 in NAFLD pathology and GH excretion activation from the pituitary gland by peripheral autonomic neural pathways relaying liver-brain-gut pathway and by central neuropeptides. METHODS: GH and IGF-1 levels were assessed in wild-type and melanocortin-4 receptor knockout mice upon the development of diet-induced NAFLD. The contribution of the peripheral autonomic nervous system connecting the liver-brain-gut axis was assessed by its blockade using capsaicin and that of the central nervous system was assessed by the expression of hypothalamic brain-derived neurotrophic factor (BDNF) and corticotropin-releasing factor (CRH), which activates GH release from the pituitary gland. RESULTS: In the NAFLD mouse models, the levels of GH and IGF-1 increased (p < .05). Further, hepatic fatty infiltration was suppressed even under peripheral autonomic nervous system blockade (p < .001), which inhibited gastric ghrelin expression. In mice with peripheral autonomic nervous blockade, hypothalamic BDNF and CRH were inhibited (p < .05), resulting in GH and IGF-1 excretion, whereas other neuropeptides of somatostatin and cortistatin showed no changes. These complementary effects were canceled in melanocortin-4 receptor knockout mice, which diminished BDNF and CRH release control. CONCLUSIONS: Our study demonstrates that the release of IGF-1 by the nervous system is a key factor in maintaining the pathological homeostasis of NAFLD, suggesting its therapeutic potential.

Letrozole ameliorates liver fibrosis through the inhibition of the CTGF pathway and 17ß-hydroxysteroid dehydrogenase 13 expression.

BACKGROUND: To establish a treatment option for liver fibrosis, the possibility of the drug repurposing theory was investigated, with a focus on the off-target effects of active pharmaceutical ingredients. METHODS: First, several active pharmaceutical ingredients were screened for their effects on the gene expression in the hepatocytes using chimeric mice with humanized hepatocytes. As per the gene expression-based screening assay for 36 medications, we assessed the mechanism of the antifibrotic effect of letrozole, a third-generation aromatase inhibitor, in mouse models of liver fibrosis induced by carbon tetrachloride (CCl4) and a methionine choline-deficient (MCD) diet. We assessed liver histology, serum biochemical markers, and fibrosis-related gene and protein expressions in the hepatocytes. RESULTS: A gene expression-based screening assay revealed that letrozole had a modifying effect on fibrosis-related gene expression in the hepatocytes, including YAP, CTGF, TGF-ß, and CYP26A1. Letrozole was administered to mouse models of CCl4- and MCD-induced liver fibrosis and it ameliorated the liver fibrosis. The mechanisms involved the inhibition of the Yap-Ctgf profibrotic pathway following a decrease in retinoic acid levels in the hepatocytes caused by suppression of the hepatic retinol dehydrogenase, Hsd17b13 and activation of the retinoic acid hydrogenase, Cyp26a1. CONCLUSIONS: Letrozole slowed the progression of liver fibrosis by inhibiting the Yap-Ctgf pathway. The mechanisms involved the modification of the Hsd17b13 and Cyp26a1 expressions led to the suppression of retinoic acid in the hepatocytes, which contributed to the activation of Yap-Ctgf pathway. Because of its off-target effect, letrozole could be repurposed for the treatment of liver fibrosis. The third-generation aromatase inhibitor letrozole ameliorated liver fibrosis by suppressing the Yap-Ctgf pathway by partially modifying the Hsd17b13 and Cyp26a1 expressions, which reduced the retinoic acid level in the hepatocytes. The gene expression analysis using chimeric mice with humanized liver revealed that the mechanisms are letrozole specific and, therefore, may be repurposed for the treatment of liver fibrosis.

Involvement of the liver-gut peripheral neural axis in nonalcoholic fatty liver disease pathologies via hepatic HTR2A.

Serotonin (5-HT) is one of the key bioamines of nonalcoholic fatty liver disease (NAFLD). Its mechanism of action in autonomic neural signal pathways remains unexplained; hence, we evaluated the involvement of 5-HT and related signaling pathways via autonomic nerves in NAFLD. Diet-induced NAFLD animal models were developed using wild-type and melanocortin 4 receptor (MC4R) knockout (MC4RKO) mice, and the effects of the autonomic neural axis on NAFLD physiology, 5-HT and its receptors (HTRs), and lipid metabolism-related genes were assessed by applying hepatic nerve blockade. Hepatic neural blockade retarded the progression of NAFLD by reducing 5-HT in the small intestine, hepatic HTR2A and hepatic lipogenic gene expression, and treatment with an HTR2A antagonist reproduced these effects. The effects were milder in MC4RKO mice, and brain 5-HT and HTR2C expression did not correlate with peripheral neural blockade. Our study demonstrates that the autonomic liver-gut neural axis is involved in the etiology of diet-induced NAFLD and that 5-HT and HTR2A are key factors, implying that the modulation of the axis and use of HTR2A antagonists are potentially novel therapeutic strategies for NAFLD treatment. This article has an associated First Person interview with the first author of the paper.

Effects of Atezolizumab and Bevacizumab on Adrenal Gland Metastasis of Hepatocellular Carcinoma: A Case Report and Review of Literature.

Regarding the prognosis of cases with advanced-stage hepatocellular carcinoma (HCC), a recent clinical study showed that the immune checkpoint inhibitors atezolizumab plus bevacizumab have superior efficacy to sorafenib. However, only a few reports have focused on their effects on extrahepatic metastases. We herein report a case of HCC in a 59-year-old man with intrahepatic lesions treated successfully by hepatic arterial chemoembolization, radiotherapy, and sorafenib; the extrahepatic lesion in the adrenal gland was treated by atezolizumab plus bevacizumab. The patient showed a tumor-free condition for one year. We have summarized the clinical course and reviewed the literature to underscore the efficacy of atezolizumab plus bevacizumab for treating extrahepatic lesions of HCC.

Cyclin D1 Binding Protein 1 Responds to DNA Damage through the ATM-CHK2 Pathway.

Cyclin D1 binding protein 1 (CCNDBP1) is considered a tumor suppressor, and when expressed in tumor cells, CCNDBP1 can contribute to the viability of cancer cells by rescuing these cells from chemotherapy-induced DNA damage. Therefore, this study focused on investigating the function of CCNDBP1, which is directly related to the survival of cancer cells by escaping DNA damage and chemoresistance. Hepatocellular carcinoma (HCC) cells and tissues obtained from Ccndbp1 knockout mice were used for the in vitro and in vivo examination of the molecular mechanisms of CCNDBP1 associated with the recovery of cells from DNA damage. Subsequently, gene and protein expression changes associated with the upregulation, downregulation, and irradiation of CCNDBP1 were assessed. The overexpression of CCNDBP1 in HCC cells stimulated cell growth and showed resistance to X-ray-induced DNA damage. Gene expression analysis of CCNDBP1-overexpressed cells and Ccndbp1 knockout mice revealed that Ccndbp1 activated the Atm-Chk2 pathway through the inhibition of Ezh2 expression, accounting for resistance to DNA damage. Our study demonstrated that by inhibiting EZH2, CCNDBP1 contributed to the activation of the ATM-CHK2 pathway to alleviate DNA damage, leading to chemoresistance.

Modulation of serotonin in the gut-liver neural axis ameliorates the fatty and fibrotic changes in non-alcoholic fatty liver.

The etiology of non-alcoholic fatty liver disease (NAFLD) consists of various factors, including neural signal pathways. However, the molecular mechanisms of the autonomic neural signals influencing NAFLD progression have not been elucidated. Therefore, we examined the involvement of the gut-liver neural axis in NAFLD development and tested the therapeutic effect of modulation of this axis in this study. To test the contribution of the gut-liver neural axis, we examined NAFLD progression with respect to body weight, hepatic steatosis, fibrosis, intestinal tight junction, microbiota and short-chain fatty acids in NAFLD models of choline-deficient defined L-amino-acid and high-fat diet-fed mice with or without blockades of autonomic nerves from the liver. Blockade of the neural signal from the liver to the gut in these NAFLD mice models ameliorated the progression of liver weight, hepatic steatosis and fibrosis by modulating serotonin expression in the small intestine. It was related to the severity of the liver pathology, the tight junction protein expression, microbiota diversity and short-chain fatty acids. These effects were reproduced by administrating serotonin antagonist, which ameliorated the NAFLD progression in the NAFLD mice models. Our study demonstrated that the gut-liver neural axis is involved in the etiologies of NAFLD progression and that serotonin expression through this signaling network is the key factor of this axis. Therefore, modulation of the gut-liver neural axis and serotonin antagonist ameliorates fatty and fibrotic changes in non-alcoholic fatty liver, and can be a potential therapeutic target of NAFLD.This article has an associated First Person interview with the first author of the paper.

Effect of Lenvatinib on a Hepatocellular Carcinoma with Fibroblast Growth Factor Receptor 4 Expression: A Case Report and Review of the Literature.

Basic and clinical research have shown that the expression of molecules involved in the hepatocellular carcinoma (HCC) cell signaling pathway is related to the sensitivity to molecular-targeted agents. We herein report a case of HCC that was effectively treated with lenvatinib after a poor response to sorafenib. The tumor showed a high expression of fibroblast growth factor receptor 4, which is reportedly related to the sensitivity to lenvatinib in vitro. The information obtained from this case and from our literature review highlights the importance of assessing the expression of the molecules involved in tumors for effective precision medicine.

Cytapheresis for pyoderma gangrenosum associated with inflammatory bowel disease: A review of current status.

Pyoderma gangrenosum (PG) is a neutrophilic dermatosis clinically characterized by the presence of painful skin ulcerations with erythematous. As it is frequently associated with inflammatory bowel diseases, including ulcerative colitis, gastroenterologists should be familiar with the disease including therapeutic options. Therefore, we have conducted a review focusing on the cytapheresis for PG in cases of inflammatory bowel diseases. A literature search was conducted to extract studies published in the last 20 years, with information on demographics, clinical symptoms, treatment, and the clinical course from a total of 22 cases reported and our recent case. In most patients, cytapheresis was associated with improvement or resolution of PG after failure of conventional therapeutic options such as corticosteroids, antibiotics, immunosuppressive agents and immunoglobulin. Based on the information summarized, cytapheresis is helpful in the majority of patients with PG refractory to medical treatment associated with inflammatory bowel diseases and could be further studied in a multicenter, randomized trial.

Ghrelin-insulin-like growth factor-1 axis is activated via autonomic neural circuits in the non-alcoholic fatty liver disease.

BACKGROUND: The correlation of the growth hormone (GH) and insulin-like growth factor-1 (IGF-1) with non-alcoholic fatty liver disease (NAFLD) has been reported in epidemiological studies. However, the mechanisms of molecular and inter-organ systems that render these factors to influence on NAFLD have not been elucidated. In this study, we examined the induction of ghrelin which is the GH-releasing hormone and IGF-1, and involvement of autonomic neural circuits, in the pathogenesis of NAFLD. METHODS: The expression of gastric and hypothalamic ghrelin, neural activation in the brain, and serum IGF-1 were examined in NAFLD models of choline-deficient defined l-amino-acid diet-fed, melanocortin 4 receptor knockout mice, and partial hepatectomy mice with or without the blockades of autonomic nerves to test the contribution of neural circuits connecting the brain, liver, and stomach. KEY RESULTS: The fatty changes in the liver increased the expression of gastric ghrelin through the autonomic pathways which sends the neural signals to the arcuate nucleus in the hypothalamus through the afferent vagal nerve which reached the pituitary gland to release GH and then stimulate the IGF-1 release from the liver. In addition, high levels of ghrelin expression in the arcuate nucleus were correlated with NAFLD progression regardless of the circuits. CONCLUSIONS: Our study demonstrated that the fatty liver stimulates the autonomic nervous signal circuits which suppress the progression of the disease by activating the gastric ghrelin expression, the neural signal transduction in the brain, and the release of IGF-1 from the liver.

Inhibition of sodium-glucose cotransporter 2 ameliorates renal injury in a novel medaka model of nonalcoholic steatohepatitis-related kidney disease.

The effect of sodium-glucose cotransporter 2 inhibitor (SGLT2I) on nonalcoholic steatohepatitis (NASH) has been reported, but there are few studies on its effect on NASH-related renal injury. In this study, we examined the effect of SGLT2I using a novel medaka fish model of NASH-related kidney disease, which was developed by feeding the d-rR/Tokyo strain a high-fat diet. SGLT2I was administered by dissolving it in water of the feeding tank. SGLT2I ameliorates macrophage accumulation and oxidative stress and maintained mitochondrial function in the kidney. The results demonstrate the effect of SGLT2I on NASH-related renal injury and the usefulness of this novel animal model for research into NASH-related complications.

Rare Mesenteric Arterial Diseases: Fibromuscular Dysplasia and Segmental Arterial Mediolysis and Literature Review.

Fibromuscular dysplasia (FMD) and segmental arterial mediolysis (SAM) are noninflammatory, nonatherosclerotic arterial diseases that cause aneurysm, occlusion, and thromboses. These diseases are rarely seen in mesenteric arterial lesions; however, as they can be lethal if appropriate management is not provided, the accumulation of clinical information from cases is essential. We herein report the cases of a 57-year-old man diagnosed with FMD and a 63-year-old man diagnosed with SAM. We conclude that an early diagnosis with imaging modalities and clinical information followed by the appropriate treatment improves the prognosis of these arterial diseases.

Effective prevention of sorafenib-related vascular damage induced adverse events and maintenance of hepatic function by dried bonito broth and histidine.

Background: Sorafenib (SOR) is an anti-angiogenic chemotherapeutic that prolongs the survival rates of patients with hepatocellular carcinoma. However, SOR also damages normal vasculature and causes associated adverse events, including hand-foot syndrome and hypertension (HT). We previously reported in an animal study that vascular damage resulted in the narrowing of the normal vascular dimension area in medaka fish (Oryzias), and histidine (HIS), a major amino acid contained in dried bonito broth (DBB), prevented these changes. Therefore, in the study, we analyzed the effects of DBB and HIS on SOR-related vascular damages and associated adverse events in patients. Materials and methods: Three-dimensional (3D) vascular images of abdominal regions reconstituted from computed tomography were assessed to compare vascular diameter prior to and following SOR administration in groups receiving SOR monotherapy, DBB+SOR, and HIS+SOR. The clinical courses of hand-foot syndrome and HT and the toxicities of SOR in biochemical assays were monitored and compared between the groups. Correlations between hepatic function and SOR-related changes in the portal venous area dimension were also assessed. Results: SOR-related vascular damage revealed narrowing of the normal abdominal vasculature in the human body, which was monitored using 3D images. The damage was ameliorated by DBB and HIS, however, HIS had a more marked effect, particularly on the renal arteries and portal vein (PV). Maintenance of blood flow contributed to the maintenance of total cholesterol, prothrombin time, albumin (ALB), and renal functions. Changes in the 3D vascular area dimension of the PV and level of serum ALB were significantly correlated. The occurrences of the clinical symptoms of hand-foot syndrome and HT were lower in the DBB- and HIS-treated groups. Conclusion: Our results clearly demonstrate that DBB and HIS prevented SOR-related abdominal vascular damage and effectively maintained hepatic function, and prevented clinical symptoms and toxicity. Trial registration: This study was registered with the University Hospital Medical Information Network Clinical Trials Registry (UMIN000025937 and UMIN000026898).

Inhibition of sodium glucose cotransporter 2 (SGLT2) delays liver fibrosis in a medaka model of nonalcoholic steatohepatitis (NASH).

The rise in the incidence of nonalcoholic steatohepatitis (NASH) has necessitated the development of an effective prevention methodology. An antidiabetic drug, belonging to the group of sodium glucose cotransporter 2 (SGLT2) inhibitors, has been tested for its therapeutic effect on NASH; however, no studies to date have demonstrated the preventive effect of an SGLT2 inhibitor on the histological progression of steatosis and fibrosis in a sequential manner in animal models. In the present study, we examined the effect of the SGLT2 inhibitor, tofogliflozin (Tofo), on NASH liver tissue using medaka as an animal model, maintaining a feeding amount and drug concentration in all animal bodies. We generated a medaka NASH model by feeding d-rR/Tokyo medaka a high-fat diet and administered Tofo by dissolving the drug directly in the water of the feeding tank. Thereafter, the effects of Tofo on body weight (BW), liver weight, hepatotoxicity, fatty infiltration, and fibrotic changes in the liver were examined. We report here that SGLT2 is expressed in medaka fish and that Tofo inhibits the accumulation of fatty tissue and delays the progression of liver fibrosis in the medaka NASH model by inhibiting increases in blood sugar, serum lipids, and transaminase, irrespective of changes in BW. These results suggest that Tofo is effective for treating NASH and that the medaka model may be useful for developing new therapeutic drugs for this disease.

Diagnosis and management of fibromuscular dysplasia and segmental arterial mediolysis in gastroenterology field: A mini-review.

The vascular diseases including aneurysm, occlusion, and thromboses in the mesenteric lesions could cause severe symptoms and appropriate diagnosis and treatment are essential for managing patients. With the development and improvement of imaging modalities, diagnostic frequency of these vascular diseases in abdominal lesions is increasing even with the small changes in the vasculatures. Among various vascular diseases, fibromuscular dysplasia (FMD) and segmental arterial mediolysis (SAM) are noninflammatory, nonatherosclerotic arterial diseases which need to be diagnosed urgently because these diseases could affect various organs and be lethal if the appropriate management is not provided. However, because FMD and SAM are rare, the cause, prevalence, clinical characteristics including the symptoms, findings in the imaging studies, pathological findings, management, and prognoses have not been systematically summarized. Therefore, there have been neither standard diagnostic criteria nor therapeutic methodologies established, to date. To systematically summarize the information and to compare these disease entities, we have summarized the characteristics of FMD and SAM in the gastroenterological regions by reviewing the cases reported thus far. The information summarized will be helpful for physicians treating these patients in an emergency care unit and for the differential diagnosis of other diseases showing severe abdominal pain.

Autonomic nervous system network and liver regeneration.

To date, various signal transducers, cytokines, growth factors, and hormones have been reported to play an important role in homeostasis of various organs. Various cells and organs are involved in the hepatic regeneration process, which proceeds as a result of the coordination of many factors. While these factors are well known to be involved in the liver regeneration after the liver injury, however, as the details of such mechanisms have not been sufficiently elucidated, the practical applicability of hepatic regeneration based on the action of these and cytokines growth factors is still unclear. In terms of the involvement of the autonomic nervous system in hepatic regeneration, cell proliferation resulting from direct signal transduction to the liver has also been reported and recent studies focusing on the inter-organ communication via neural network opened a novel aspect of this field for therapeutic applicability. Therefore, the appropriate understanding of the relationship between autonomic neural network and liver regeneration through various organs including brain, afferent nerve, efferent nerve, etc. is essential. This mini-review explains the principle of neural system involved in the inter-organ communication and its contribution on the liver regeneration upon the liver injury reviewing recent progress in this field.

Evaluation of the branched-chain amino acid-to-tyrosine ratio prior to treatment as a prognostic predictor in patients with liver cirrhosis.

This study evaluated whether the branched-chain amino acid-to-tyrosine ratio (BTR) is a prognostic predictive factor in patients with liver cirrhosis by determining the relationship of the BTR with event-free survival in a retrospective, observational cohort study. The medical records of patients with liver cirrhosis who visited our institution from February 2000 to May 2012 were examined. Events due to liver cirrhosis were defined as death, worsening of esophageal and/or gastric varices, hepatocellular carcinoma, and liver failure. The primary endpoint was the period from the date of BTR measurement until the first onset of these events. Event-free survival was compared between patients with BTR ≥ 4 and BTR < 4. Relationships between the BTR and other factors predicting prognosis were also examined. Event-free survival was evaluated in patients with and without branched-chain amino acid supplementation using propensity score matching. Significantly longer event-free survival was found in liver cirrhosis patients with BTR ≥ 4 (n = 425) compared with those with BTR < 4 (n = 105), and the BTR was associated with liver cirrhosis events. The BTR showed significant relationships with other predictive factors evaluated. In subcohorts matched by propensity score, branched-chain amino acid supplementation significantly improved event-free survival in patients with BTR <4. The BTR is clinically useful for predicting prognosis in liver cirrhosis patients. BCAA supplementation may be beneficial in those with BTR < 4.

Effect of treatment support on preventing local recurrence of hepatocellular carcinoma directly adjacent to the diaphragm.

Treatment support is anticipated to improve the results of radiofrequency ablation (RFA) treatment in cases in which visualization of tumors using the conventional B-mode is unclear. In the present study, the effectiveness of treatment support for RFA reducing the local recurrence rate of hepatocellular carcinoma (HCC) that are located directly adjacent to the diaphragm, and which are difficult to visualize with B-mode ultrasound imaging, was investigated. A total of 103 HCC tumors measuring <5 cm, which were located abutting the diaphragm, and which were difficult to visualize using the B-mode, were treated using RFA. Thirty-three of those HCC tumors were treated using RFA without treatment support, whereas the remaining 70 HCC tumors were treated using RFA with treatment support, including artificial pleural effusion, contrast-enhanced ultrasonography (CEUS) with the contrasting agent, Sonazoid™, and fusion imaging, either alone or in combination to improve the visualization of the tumors. The rate of local recurrence, and factors affecting local recurrence, were analyzed. Local recurrences were confirmed in 17 of the 103 nodules (16.50%). The overall rate of local recurrence was 13.1% at 6 months, and 20.2% at 12 months. The rate of local recurrence using RFA with artificial pleural effusion was significantly lower compared with those cases of HCC tumors treated without artificial pleural effusion (P=0.008). Similarly, the rate of local recurrence for CEUS RFA with Sonazoid™ was significantly lower compared with those cases of HCC tumors treated without Sonazoid™ (P=0.00081). In a multivariate analysis, CEUS RFA with Sonazoid™ and artificial pleural effusion contributed to the decrease in the rate of local recurrence (hazard ratios, 0.075 and 0.143, respectively). Based on these results, it is possible to conclude that CEUS with Sonazoid™ as a treatment support was the most effective method for reducing the rate of local recurrences abutting the diaphragm that are difficult to visualize using B-mode ultrasonography.

Percutaneous transhepatic obliteration and percutaneous transhepatic sclerotherapy for intractable hepatic encephalopathy and gastric varices improves the hepatic function reserve.

Percutaneous transhepatic obliteration (PTO) and percutaneous transhepatic sclerotherapy (PTS) are widely performed as an emergency measure in cases of variceal hemorrhage and intractable hepatic encephalopathy. The PTO/PTS technique is capable of directly blocking the blood supply in cases in which balloon-occluded retrograde transvenous obliteration (B-RTO) is not effective, or in cases with complicated collateral flow. Although PTO/PTS is not currently the first choice due to the invasiveness of transhepatic puncture, this procedure can modify the blood flow in an antegrade manner. The present study examined the changes in hepatic function reserve following PTO/PTS for intractable hepatic encephalopathy and/or gastric varices. In total, the study included 37 patients (mean age, 61.75±12.77 years; age range, 32-88 years; male to female ratio, 23:14) with a variety of gastrorenal shunts, or B-RTO-intractable hepatic encephalopathy and gastric varices without gastrorenal shunts. The patients underwent PTO/PTS by embolizing a microcoil or injection of a sclerosing agent (5% ethanolamine oleate iopamidol). Alterations in hepatic function reserve prior to and following the procedure were compared. The patients were treated for hepatic encephalopathy in 11 patients, gastric varices in 19 patients, and both conditions in 7 patients. The results indicated that the blood ammonia level improved from 135.76±75.23 mg/dl to 88.00±42.16 and 61.81±33.75 mg/dl at 3 and 6 months after therapy, respectively. In addition, the Child-Pugh score improved from 8.48±2.01 prior to therapy to 7.70±1.84 and 7.22±2.01 at 3 and 6 months after the procedure, respectively. Although there was a concern that PTO/PTS may cause complications due to an increase in portal venous pressure (PVP) arising from shunt occlusion, no severe complications were observed. In conclusion, for patients with various gastrorenal shunts or those with B-RTO-intractable hepatic encephalopathy and gastric varices without gastrorenal shunts, PTO/PTS can improve the antegrade blood flow to the liver, as demonstrated by improvement in the hepatic function reserve.