Dietary Fiber from Oat and Rye Brans Ameliorate Western Diet-Induced Body Weight Gain and Hepatic Inflammation by the Modulation of Short-Chain Fatty Acids, Bile Acids, and Tryptophan Metabolism.

SCOPE: Dietary fiber (DF) induces changes in gut microbiota function and thus modulates the gut environment. How this modulation is associated with metabolic pathways related to the gut is largely unclear. This study aims to investigate differences in metabolites produced by the gut microbiota and their interactions with host metabolism in response to supplementation with two bran fibers. METHODS AND RESULTS: Male C57BL/6N mice are fed a western diet (WD) for 17 weeks. Two groups of mice received a diet enriched with 10% w/w of either oat or rye bran, with each bran containing 50% DF. Microbial metabolites are assessed by measuring cecal short-chain fatty acids (SCFAs), ileal and fecal bile acids (BAs), and the expression of genes related to tryptophan (TRP) metabolism. Both brans lowered body weight gain and ameliorated WD-induced impaired glucose responses, hepatic inflammation, liver enzymes, and gut integrity markers associated with SCFA production, altered BA metabolism, and TRP diversion from the serotonin synthesis pathway to microbial indole production. CONCLUSIONS: Both brans develop a favorable environment in the gut by altering the composition of microbes and modulating produced metabolites. Changes induced in the gut environment by a fiber-enriched diet may explain the amelioration of metabolic disturbances related to WD.

Protective Effects of Black Raspberry (Rubus occidentalis) Extract against Hypercholesterolemia and Hepatic Inflammation in Rats Fed High-Fat and High-Choline Diets.

Choline is converted to trimethylamine by gut microbiota and further oxidized to trimethylamine-N-oxide (TMAO) by hepatic flavin monooxygenases. Positive correlation between TMAO and chronic diseases has been reported. Polyphenols in black raspberry (BR), especially anthocyanins, possess various biological activities. The objective of this study was to determine the effects of BR extract on the level of choline-derived metabolites, serum lipid profile, and inflammation markers in rats fed high-fat and high-choline diets. Forty female Sprague-Dawley (SD) rats were randomly divided into four groups and fed for 8 weeks as follows: CON (AIN-93G diet), HF (high-fat diet), HFC (HF + 1.5% choline water), and HFCB (HFC + 0.6% BR extract). Serum levels of TMAO, total cholesterol, and low-density lipoprotein (LDL)-cholesterol and cecal trimethylamine (TMA) level were significantly higher in the HFC than in the HFCB. BR extract decreased mRNA expression of pro-inflammatory genes including nuclear factor-κB (NF-κB), interleukin (IL)-1ß, IL-6, and cyclooxygenase-2 (COX-2), and protein expression of NF-κB and COX-2 in liver tissue. These results suggest that consistent intake of BR extract might alleviate hypercholesterolemia and hepatic inflammation induced by excessive choline with a high-fat diet via lowering elevated levels of cecal TMA and serum TMAO in rats.

Reduction of high-fat diet-induced liver proinflammatory state by eicosapentaenoic acid plus hydroxytyrosol supplementation: involvement of resolvins RvE1/2 and RvD1/2.

High-fat diet (HFD)-fed mice show obesity with development of liver steatosis and a proinflammatory state without establishing an inflammatory reaction. The aim of this work was to assess the hypothesis that eicosapentaenoic acid (EPA) plus hydroxytyrosol (HT) supplementation prevents the inflammatory reaction through enhancement in the hepatic resolvin content in HFD-fed mice. Male C57BL/6J mice were fed an HFD or a control diet and supplemented with EPA (50 mg/kg/day) and HT (5 mg/kg/day) or their respective vehicles for 12 weeks. Measurements include liver levels of EPA, DHA and palmitate (gas chromatography), liver resolvins and triglyceride (TG) and serum aspartate transaminase (AST) (specific kits) and hepatic and serum inflammatory markers (quantitative polymerase chain reaction and enzyme-linked immunosorbent assay). Compared to CD, HFD induced body weight gain, liver steatosis and TG accumulation, with up-regulation of proinflammatory markers in the absence of histological inflammation or serum AST changes; these results were accompanied by higher hepatic levels of resolvins RvE1, RvE2, RvD1 and RvD2, with decreases in EPA and DHA contents. EPA+HT supplementation in HFD feeding synergistically reduced the steatosis score over individual treatments and increased the hepatic levels of EPA, DHA and resolvins, with attenuation of proinflammatory markers. Lack of progression of HFD-induced proinflammatory state into overt inflammation is associated with resolvin up-regulation, which is further increased by EPA+HT supplementation eliciting steatosis attenuation. These findings point to the importance of combined protocols in hepatoprotection due to the involvement of cross-talk mechanisms, which increase effectiveness and diminish dosages, avoiding undesirable effects.

Caloric Restriction Prevents Carcinogen-Initiated Liver Tumorigenesis in Mice.

Caloric restriction (CR) and endurance exercise elicit wide-ranging health benefits including reduced risk of select cancers. In addition, diet composition influences oncogenesis, although its interactions with exercise and CR are not well understood. Therefore, to investigate the potential interactions between diet and lifestyle interventions on liver tumorigenesis, the carcinogen diethylnitrosamine was administered to 72 male C57Bl/6 mice that were subsequently fed diets enriched with lard (CTL) or olive oil and were further stratified to voluntary wheel running (Ex) or 30% CR for 49 weeks. Although Ex and diet composition did not influence liver oncogenesis, CR prevented hepatic tumor formation. In addition, CR reduced steatosis, hepatocyte ballooning, inflammation, and immune cell infiltration, all of which are hallmarks in the progression of nonalcoholic fatty liver disease to liver tumorigenesis. RNA sequencing of nontransformed liver tissues from CR mice revealed changes in metabolic pathways and reduced inflammation, cytokine production, stellate cell activation and migration, and genes associated with liver injury and oncogenesis. These data demonstrate that CR protects against steatosis, liver inflammation, and liver injury and is a robust deterrent of carcinogen-induced hepatic oncogenesis. Cancer Prev Res; 10(11); 660-70. ©2017 AACR.

Long-term dietary supplementation with low-dose nobiletin ameliorates hepatic steatosis, insulin resistance, and inflammation without altering fat mass in diet-induced obesity.

SCOPE: We evaluated the long-term effect of low-dose nobiletin (NOB), a polymethoxylated flavone, on diet-induced obesity and related metabolic disturbances. METHODS AND RESULTS: C57BL/6J mice were fed a high-fat diet (HFD, 45 kcal% fat) with or without NOB (0.02%, w/w) for 16 weeks. NOB did not alter food intake or body weight. Despite increases in fatty acid oxidation-related genes expression and enzymes activity in adipose tissue, NOB did not affect adipose tissue weight due to simultaneous increases in lipogenic genes expression and fatty acid synthase activity. However, NOB significantly decreased not only pro-inflammatory genes expression in adipose tissue but also proinflammatory cytokine levels in plasma. NOB-supplemented mice also showed improved glucose tolerance and insulin resistance, along with decreased levels of plasma insulin, free fatty acids, total cholesterol, non-HDL-cholesterol, and apolipoprotein B. In addition, NOB caused significant decreases in hepatic lipid droplet accumulation and triglyceride content by activating hepatic fatty acid oxidation-related enzymes. Hepatic proinflammatory TNF-α mRNA expression, collagen accumulation, and plasma levels of aminotransferases, liver damage indicators, were also significantly lower in NOB-supplemented mice. CONCLUSION: These findings suggest that long-term supplementation with low-dose NOB can protect against HFD-induced inflammation, insulin resistance, dyslipidemia, and nonalcoholic fatty liver disease, without ameliorating adiposity.

Polyphenol-rich virgin olive oil reduces insulin resistance and liver inflammation and improves mitochondrial dysfunction in high-fat diet fed rats.

SCOPE: Virgin olive oil is an essential component of the Mediterranean diet. Its antioxidant and anti-inflammatory properties are mainly linked to phenolic contents. This study aims to evaluate the beneficial effects of a polyphenol-rich virgin olive oil (HPCOO) or olive oil without polyphenols (WPOO) in rats fed high-fat diet (HFD). METHODS AND RESULTS: Male Sprague-Dawley rats were divided into four groups based on the different types of diet: (I) standard diet (STD); (II) HFD; (III) HFD containing WPOO, and (IV) HFD containing HPCOO. HPCOO and WPOO induced a significant improvement of HFD-induced impaired glucose homeostasis (by hyperglycemia, altered oral glucose tolerance, and HOMA-IR) and inflammatory status modulating pro- and anti-inflammatory cytokines (TNF-α, IL-1, and IL-10) and adipokines. Moreover, HPCOO and less extensively WPOO, limited HFD-induced liver oxidative and nitrosative stress and increased hepatic fatty acid oxidation. To study mitochondrial performance, oxidative capacity and energy efficiency were also evaluated in isolated liver mitochondria. HPCOO, but not WPOO, reduced H2 O2 release and aconitase activity by decreasing degree of coupling, which plays a major role in the control of mitochondrial reactive oxygen species emission. CONCLUSION: HPCOO limits HFD-induced insulin resistance, inflammation, and hepatic oxidative stress, preventing nonalcoholic fatty liver disease progression.

Incidence and risk of hepatic toxicities with PD-1 inhibitors in cancer patients: a meta-analysis.

PURPOSE: Anti-programmed cell death receptor-1 (PD-1) antibodies have demonstrated antitumor activity in many cancer entities. Hepatic adverse events (AEs) are one of its major side effects, but the overall risks have not been systematically evaluated. Thus, we conducted this meta-analysis to investigate the overall incidence and risk of developing hepatic AEs in cancer patients treated with PD-1 inhibitors. METHODS: PubMed, Embase, and oncology conference proceedings were searched for relevant studies. Eligible studies were randomized controlled trials of cancer patients treated with PD-1 inhibitors with adequate data on hepatic AEs. RESULTS: A total of nine randomized controlled trials with a variety of solid tumors were eligible for the meta-analysis. The use of PD-1 inhibitors significantly increased the risk of developing all-grade hepatic AEs but not for high-grade hepatic AEs in comparison with chemotherapy or everolimus control. Additionally, the risk of all-grade and high-grade hepatic AEs with a nivolumab/ipilimumab combination was substantially higher than ipilimumab. No significant differences in the risk of all-grade and high-grade hepatic AEs were found between PD-1 inhibitors monotherapy and ipilimumab. CONCLUSION: While the use of PD-1 inhibitors is associated with an increased risk of developing hepatic AEs in cancer patients, this is primarily for lower grade events.

Effects of glucomannan/spirulina-surimi on liver oxidation and inflammation in Zucker rats fed atherogenic diets.

Cholesterolemia is associated with pro-oxidative and proinflammatory effects. Glucomannan- or glucomannan plus spirulina-enriched surimis were included in cholesterol-enriched high-saturated diets to test the effects on lipemia; antioxidant status (glutathione status, and antioxidant enzymatic levels, expressions and activities); and inflammation biomarkers (endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α)) in Zucker fa/fa rats. Groups of eight rats each received diet containing squid-surimi (C), squid-surimi cholesterol-enriched diet (HC), glucomannan-squid-surimi cholesterol-enriched diet (HG), or glucomannan-spirulina-squid-surimi cholesterol-enriched diet (HGS) over a period of 7 weeks. HC diet induced severe hyperlipemia, hepatomegalia, increased inflammation markers, and impaired antioxidant status significantly (at least p < 0.05) vs. C diet. HG diet decreased lipemia and liver size and normalized antioxidant status to C group levels, but increased TNF-α with respect to HC diet (p < 0.05). In general terms, 3 g/kg of spirulina in diet maintained the positive results observed in the HG diet but, in addition, increased inflammation index [eNOS/(eNOS + iNOS)] and decreased plasma TNF-α (both p < 0.05). In conclusion, glucomannan plus a small amount of spirulina blocks negative effects promoted by hypercholesterolemic diets. Although more studies are needed, present results suggest the utility of including glucomannan and/or spirulina as functional ingredients into fish derivates to be consumed by people on metabolic syndrome risk.

Gelatinous bone marrow transformation secondary to unusual eating habits and drastic weight loss.

Gelatinous bone marrow transformation (GMT), also known as starvation bone marrow, has been reported in a number of chronic illnesses, eating disorders (anorexia nervosa) and malignancies. We report the case of a 37-year-old man with a history of bipolar disorder and obesity (weighing >300 pounds) who presented due to recently developing a deep yellow colour to his skin. Over the past 2 years, through diet and exercise, he lost over 150 pounds. He reported running 6-8 miles per day and eating 'lots of squash'. We made the diagnosis of starvation hepatitis and bone marrow degeneration, and referred the patient to a dietician and haematologist/oncologist, where improvements were observed at 4 weeks follow-up.

The effect of a low-carbohydrate, ketogenic diet on nonalcoholic fatty liver disease: a pilot study.

Nonalcoholic fatty liver disease is an increasingly common condition that may progress to hepatic cirrhosis. This pilot study evaluated the effects of a low-carbohydrate, ketogenic diet on obesity-associated fatty liver disease. Five patients with a mean body mass index of 36.4 kg/m(2) and biopsy evidence of fatty liver disease were instructed to follow the diet (<20 g/d of carbohydrate) with nutritional supplementation for 6 months. Patients returned for group meetings biweekly for 3 months, then monthly for the second 3 months. The mean weight change was -12.8 kg (range 0 to -25.9 kg). Four of 5 posttreatment liver biopsies showed histologic improvements in steatosis (P=.02) inflammatory grade (P=.02), and fibrosis (P=.07). Six months of a low-carbohydrate, ketogenic diet led to significant weight loss and histologic improvement of fatty liver disease. Further research is into this approach is warranted.

A placebo-controlled trial of pioglitazone in subjects with nonalcoholic steatohepatitis.

BACKGROUND: No pharmacologic therapy has conclusively proved to be effective for the treatment of nonalcoholic steatohepatitis, which is characterized by insulin resistance, steatosis, and necroinflammation with or without centrilobular fibrosis. Pioglitazone is a thiazolidinedione that ameliorates insulin resistance and improves glucose and lipid metabolism in type 2 diabetes mellitus. METHODS: We randomly assigned 55 patients with impaired glucose tolerance or type 2 diabetes and liver biopsy-confirmed nonalcoholic steatohepatitis to 6 months of treatment with a hypocaloric diet (a reduction of 500 kcal per day in relation to the calculated daily intake required to maintain body weight) plus pioglitazone (45 mg daily) or a hypocaloric diet plus placebo. Before and after treatment, we assessed hepatic histologic features, hepatic fat content by means of magnetic resonance spectroscopy, and glucose turnover during an oral glucose tolerance test ([14C]glucose given with the oral glucose load and [3H]glucose given by intravenous infusion). RESULTS: Diet plus pioglitazone, as compared with diet plus placebo, improved glycemic control and glucose tolerance (P<0.001), normalized liver aminotransferase levels as it decreased plasma aspartate aminotransferase levels (by 40% vs. 21%, P=0.04), decreased alanine aminotransferase levels (by 58% vs. 34%, P<0.001), decreased hepatic fat content (by 54% vs. 0%, P<0.001), and increased hepatic insulin sensitivity (by 48% vs. 14%, P=0.008). Administration of pioglitazone, as compared with placebo, was associated with improvement in histologic findings with regard to steatosis (P=0.003), ballooning necrosis (P=0.02), and inflammation (P=0.008). Subjects in the pioglitazone group had a greater reduction in necroinflammation (85% vs. 38%, P=0.001), but the reduction in fibrosis did not differ significantly from that in the placebo group (P=0.08). Fatigue and mild lower-extremity edema developed in one subject who received pioglitazone; no other adverse events were observed. CONCLUSIONS: In this proof-of-concept study, the administration of pioglitazone led to metabolic and histologic improvement in subjects with nonalcoholic steatohepatitis. Larger controlled trials of longer duration are warranted to assess the long-term clinical benefit of pioglitazone. (ClinicalTrials.gov number, NCT00227110 [ClinicalTrials.gov] .).

One-year intense nutritional counseling results in histological improvement in patients with non-alcoholic steatohepatitis: a pilot study.

BACKGROUND AND AIM: In individuals with biopsy-proven non-alcoholic steatohepatitis (NASH), short-term weight loss has been shown to improve biochemical abnormalities; however, its effect on liver histology is largely unknown. The aim of the article is to determine if dietary intervention is effective in improving histological features of steatohepatitis in patients with biopsy-proven NASH. METHODS: Twenty-three patients (11M/12F) with BMI >25 kg/m(2) and biopsy-proven NASH received standardized nutritional counseling aimed at reducing insulin resistance (IR) and weight. Blood tests were checked at baseline and every 1-4 months, and liver biopsy was repeated at month 12. IR was assessed by the homeostasis model assessment (HOMA). Liver biopsies were scored according to modified Brunt criteria for NASH. "Histologic response" was defined as a reduction in total NASH score of >/=2 points with at least one point being in the non-steatosis component. RESULTS: Sixteen patients (8M/8F) completed 12 months of dietary intervention, and 15 underwent repeat liver biopsies. At month 12, mean weight decreased from 98.3 to 95.4 kg. Mean waist circumference, visceral fat, fasting glucose, IR, triglycerides, AST, ALT, and histologic score were all reduced but the difference was not significant. Nine patients had a histologic response, six had stable scores, and none had a worsened score. Compared to patients with unchanged histologic scores, patients with improved scores had significantly greater reduction in weight, waist circumference, AST, ALT, steatosis grade, and total NASH score. CONCLUSION: Among patients who successfully completed 1 yr of intense dietary intervention, nine of 15 patients with NASH displayed histologic improvement. This pilot study suggests that dietary intervention can be effective in improving histology in patients with biopsy-proven NASH.

[Influence of ursodeoxycholic acid on the therapeutic effects of low-calorie diet in obesity and hyperlipidemia rats with steatohepatitis].

OBJECTIVE: To explore the influence of ursodeoxycholic acid on the therapeutic effects of low-calorie diet in steatohepatitis with obesity and hyperlipidemia. METHODS: Thirty-five Sprague-Dawley rats fed with high-fat diet for 10 weeks were randomly allocated into 3 groups, and continued to experiment for 2 weeks. The animals in model group (n = 10) were still fed with high-fat diet; low-calorie diet group (n = 10) with common diet but only one third of the amount of normal demand; ursodeoxycholic acid group (n = 15) with low-calorie diet and ursodeoxycholic acid (15 mg/kg.d(-1)); and another 9 rats with common diet for 12 weeks as normal group. RESULTS: Compared with normal group, such indexes as body weight, liver weight, and the level of serum lipids and aminotransferase were all increased significantly in model group. Furthermore, all rats in model group developed steatohepatitis. On the other hand, such indexes as body weight and the degree of steatosis in rats of low-calorie diet group were decreased sharply compared with those in model group, but neither disorders of serum lipid nor the degree of hepatic inflammation and necrosis in low-calorie diet group were improved obviously. Disorders of serum lipid, aspartate aminotransferase, hepatic inflammation and necrosis in ursodeoxycholic acid group were ameliorated to some extent. CONCLUSIONS: Ursodeoxycholic acid might help to improve the therapeutic effects of low-calorie diet on steatohepatitis with obesity and hyperlipidemia.

Plasma transforming growth factor-beta1 level and efficacy of alpha-tocopherol in patients with non-alcoholic steatohepatitis: a pilot study.

BACKGROUND: Non-alcoholic steatohepatitis is a distinct entity, characterized by fatty change, lobular inflammation and fibrosis of the liver. Some cases of non-alcoholic steatohepatitis progress to cirrhosis, but it is not easy to distinguish this disease from non-alcoholic fatty liver by non-invasive examinations. No proven therapy for non-alcoholic steatohepatitis exists. Transforming growth factor-beta1 is implicated in the development of liver fibrosis, and is inhibited by alpha-tocopherol (vitamin E) in the liver. Therefore, in this study, the significance of the measurement of the level of plasma transforming growth factor-beta1 and the effect of alpha-tocopherol on the clinical course of non-alcoholic steatohepatitis were investigated. METHODS: Twelve patients with non-alcoholic steatohepatitis and 10 patients with non-alcoholic fatty liver, with a diagnosis confirmed by liver biopsy, were studied. None of the patients had a history of alcohol abuse, habitual medicine or malignant or inflammatory diseases. All patients were negative for hepatitis B, C and G virus. Patients were given dietary instruction for 6 months, and then alpha-tocopherol (300 mg/day) was given for 1 year. Blood chemistries, measurement of plasma transforming growth factor-beta1 level and liver biopsies were undertaken before and after the 1-year alpha-tocopherol treatment. RESULTS: The serum alanine transaminase level decreased in non-alcoholic fatty liver patients, but not in non-alcoholic steatohepatitis patients, after 6 months of dietary therapy. Although the serum alanine transaminase level in non-alcoholic steatohepatitis patients was reduced during the 1-year alpha-tocopherol treatment, alpha-tocopherol had no effect on the serum alanine transaminase level in non-alcoholic fatty liver patients. The histological findings, such as steatosis, inflammation and fibrosis, of the non-alcoholic steatohepatitis patients were improved after alpha-tocopherol treatment. The plasma transforming growth factor-beta1 level in non-alcoholic steatohepatitis patients was significantly elevated compared with that in non-alcoholic fatty liver patients and healthy controls, and decreased, accompanied by an improvement in serum alanine transaminase level, with alpha-tocopherol treatment. CONCLUSIONS: Our data suggest that the measurement of the level of plasma transforming growth factor-beta1 represents a possible method of distinguishing between non-alcoholic steatohepatitis and non-alcoholic fatty liver. Long-term alpha-tocopherol treatment may be safe and effective for non-alcoholic steatohepatitis. A randomized, controlled, double-blind trial is needed to confirm the full potential of alpha-tocopherol in the management of non-alcoholic steatohepatitis.