Insulin resistance, obesity, and liver cancer

Diabetes risk reduction diet and risk of liver cancer and chronic liver disease mortality: A prospective cohort study

BACKGROUND

We aimed to prospectively evaluate the association between a diabetes risk reduction diet (DRRD) score and the risk of liver cancer development and chronic liver disease-specific mortality.

METHODS

We included 98,786 postmenopausal women from the Women's Health Initiative-Observational Study and the usual diet arm of the Diet Modification trial. The DRRD score was derived from eight factors: high intakes of dietary fiber, coffee, nuts, polyunsaturated fatty acids, low intakes of red and processed meat, foods with high glycemic index, sugar-sweetened beverages (SSBs), and trans fat based on a validated Food-Frequency Questionnaire administered at baseline (1993-1998). Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) for liver cancer incidence and chronic liver disease mortality were estimated using Cox proportional hazards regression models.

RESULTS AND CONCLUSION

After a median follow-up of 22.0 years, 216 incident liver cancer cases and 153 chronic liver disease deaths were confirmed. A higher DRRD score was significantly associated with a reduced risk of developing liver cancer (HRTertile 3 vs. Tertile 1 = 0.69; 95% CI: 0.49-0.97; Ptrend = 0.03) and chronic liver disease mortality (HRT3 vs. T1 = 0.54; 95% CI: 0.35-0.82; Ptrend = 0.003). We further found inverse associations with dietary fiber and coffee, and positive associations with dietary glycemic index, SSBs, and trans fat. A higher DRRD score was associated with reduced risk of developing liver cancer and chronic liver disease mortality among postmenopausal women.

Triglyceride-Glucose Index is an Independent Risk Factor for Hepatocellular Carcinoma Development in Patients with HBV-Related Liver Cirrhosis

Aim

This study aimed to explore the effects of the triglyceride-glucose (TyG) index on hepatocellular carcinoma (HCC) development in patients with hepatitis B virus (HBV)-related liver cirrhosis (LC).

Methods

A total of 242 patients with HBV-related LC were enrolled and followed-up. Logistic regression analysis was performed to investigate risk factors for HCC.

Results

The median follow-up time was 37 months (range: 6-123 months). At the end of the follow-up, 11 (11.3%) patients with compensated cirrhosis (CC) and 45 (31.0%) with decompensated cirrhosis (DC) developed HCC. The TyG index was higher in the HCC group than in the non-HCC group (P=0.05). Univariate analysis showed that age (P<0.01), DC (P<0.01), TyG index (P=0.08), albumin (ALB) level (P=0.05), platelet (PLT) count (P<0.01), and HBV DNA positivity (P<0.01) were associated with HCC development. Multivariate analysis revealed that age, DC, TyG index, PLT count, and HBV DNA positivity were independent risk factors for HCC development (P=0.01, 0.01, <0.01, 0.05, and <0.01, respectively). For patients with DC, multivariate logistic regression analysis revealed that age, TyG index, and HBV DNA positivity were independent risk factors for HCC development (all P<0.05). A new model encompassing age, DC, TyG, PLT, and positive HBV DNA had optimal predictive accuracy in patients with DC or CC, with a cutoff value of 0.197. The areas under the receiver operating characteristic curves (AUROCs) of the model for predicting HCC development in patients with LC, DC, and CC were 0.778, 0.721, and 0.783, respectively.

Conclusion

TyG index was identified as an independent risk factor for HCC development in patients with LC.

Insulin Resistance: The Increased Risk of Cancers

Insulin resistance, also known as impaired insulin sensitivity, is the result of a decreased reaction of insulin signaling to blood glucose levels. This state is observed when muscle cells, adipose tissue, and liver cells, improperly respond to a particular concentration of insulin. Insulin resistance and related increased plasma insulin levels (hyperinsulinemia) may cause metabolic impairments, which are pathological states observed in obesity and type 2 diabetes mellitus. Observations of cancer patients confirm that hyperinsulinemia is a major factor influencing obesity, type 2 diabetes, and cancer. Obesity and diabetes have been reported as risks of the initiation, progression, and metastasis of several cancers. However, both of the aforementioned pathologies may independently and additionally increase the cancer risk. The state of metabolic disorders observed in cancer patients is associated with poor outcomes of cancer treatment. For example, patients suffering from metabolic disorders have higher cancer recurrence rates and their overall survival is reduced. In these associations between insulin resistance and cancer risk, an overview of the various pathogenic mechanisms that play a role in the development of cancer is discussed.

Life-course adiposity and severe liver disease: a Mendelian randomization analysis

OBJECTIVE

There is little evidence on the genetic associations between life-course adiposity (including birth weight, childhood BMI, and adulthood BMI) and severe liver disease (SLD; including cirrhosis and liver cancer). The current study aimed to examine and contrast these associations.

METHODS

Genetic variants were obtained from genome-wide association studies. Two-sample Mendelian randomization (MR) analyses were performed to assess the genetic associations of life-course adiposity with SLD and liver biomarkers. Cox regression was used to estimate adjusted hazard ratios for SLD associated with genetic risk scores of life-course adiposity and adulthood weight change in the China Kadoorie Biobank.

RESULTS

In observational analyses, genetic predispositions to childhood adiposity and adulthood adiposity were each associated with SLD. There was a U-shaped association between adulthood weight change and risk of SLD. In meta-analyses of MR results, genetically predicted 1-standard deviation increase in birth weight was inversely associated with SLD at a marginal significance (odds ratio: 0.81 [95% CI: 0.65-1.00]), whereas genetically predicted 1-standard deviation higher childhood BMI and adulthood BMI were positively associated with SLD (odds ratio: 1.27 [95% CI: 1.05-1.55] and 1.79 [95% CI: 1.59-2.01], respectively). The results of liver biomarkers mirrored those of SLD.

CONCLUSIONS

The current study provided genetic evidence on the associations between life-course adiposity and SLD.

Population-attributable risk of modifiable lifestyle factors to hepatocellular carcinoma: The multi-ethnic cohort

BACKGROUND AND AIMS

Lifestyle factors are well associated with risk of hepatocellular carcinoma (HCC). However, the impact of reducing adverse lifestyle behaviours on population-level burden of HCC is uncertain.

METHODS

We conducted prospective analysis of the population-based multi-ethnic cohort (MEC) with linkage to cancer registries. The association of lifestyle factors (smoking, alcohol, diet quality assessed by alternate Mediterranean diet score, coffee drinking, physical activity and body mass index) with HCC incidence was examined using Cox regression. Population-attributable risk (PAR, %) for the overall, lean and overweight/obese populations was determined.

RESULTS

A total of 753 incident cases of HCC were identified in 181,346 participants over median follow-up of 23.1 years. Lifestyle factors associated with elevated HCC risk included former/current smoking, heavy alcohol use, poor diet quality, lower coffee intake and obesity, but not physical activity. The lifestyle factor with highest PAR was lower coffee intake (21.3%; 95% CI: 8.9%-33.0%), followed by current smoking (15.1%; 11.1%-19.0%), obesity (14.5%; 9.2%-19.8%), heavy alcohol use (7.1%; 3.5%-10.6%) and lower diet quality (4.1%; 0.1%-8.1%). The combined PAR of all high-risk lifestyle factors was 51.9% (95% CI: 30.1%-68.6%). A higher combined PAR was observed among lean (65.2%, 26.8%-85.7%) compared to overweight/obese (37.4%, 11.7%-58.3%) participants. Adjusting for viral hepatitis status in a linked MEC-Medicare dataset resulted in similar PAR results.

CONCLUSIONS

Modifying lifestyle factors, particularly coffee intake, may have a substantial impact on HCC burden in diverse populations, with greater impact among lean adults. Diet and lifestyle counselling should be incorporated into HCC prevention strategies.

Influence of AFP on surgical outcomes in non-B non-C patients with curative resection for hepatocellular carcinoma

To study the clinical and prognostic features of non-B non-C alpha-fetoprotein (AFP)(-)-hepatocellular carcinoma (HCC) (NBNC-AFP(-)-HCC) and the relationship between the prognostic features of HCC and hepatitis B virus surface antigen (HBsAg) status and AFP. We enrolled 227 patients who underwent hepatic resection for HCC between January 1998 and December 2007 at Sun Yat-sen University Cancer Center, all of whom were diagnosed with HCC by pathology. All patients were stratified into one of four groups (B-AFP(+)-HCC, B-AFP(-)-HCC, NBNC-AFP(+)-HCC, and NBNC-AFP(-)-HCC) according to AFP levels and HBsAg status. The clinicopathologic and survival characteristics of NBNC-AFP(-)-HCC patients were compared with those of all other three groups. Out of the 105 NBNC-HCC patients, 43 patients (40.9%) had AFP-negative HCC. There were some differences in factors between the B-AFP(+) and NBNC-AFP(-) patients, such as age, body mass index (BMI), diabetes, and ALT (P < 0.05). On univariate analysis, tumour size, secondary tumour, and portal invasion were prognostic factors for overall survival (OS) and disease-free survival (DFS) (P < 0.05). Cox multivariate regression analysis suggested that tumour size and tumour number (P < 0.05) were independent predictors. In addition, compared with the B-AFP(+)-HCC, B-AFP(-)-HCC, and NBNC-AFP(+)-HCC groups, the NBNC-AFP(-)-HCC patients had the best DFS (P < 0.05). Compared with the B-AFP(+)-HCC and NBNC-AFP(+)-HCC groups, the NBNC-AFP(-)-HCC patients had better OS (P < 0.05), and survival rates were similar to those of B-AFP(-)-HCC patients. NBNC-AFP(-)-HCC patients had a relatively favourable prognosis. It can serve as a useful marker in predicting the risk of tumour recurrence in the early stages.

Associations between serum glucose, insulin, insulin resistance and the risk of incident primary liver cancer or chronic liver disease mortality: a nested case-control study

BACKGROUND

To evaluate the associations between pre-diagnostic levels of serum insulin, glucose and insulin resistance (HOMA-IR) and future risk of incident primary liver cancer (PLC) or chronic liver disease (CLD)-related mortality.

METHODS

We used a nested case-control design to evaluate subjects over 22 years of follow-up. Glucose, insulin, and three markers of hepatitis B virus (HBV) and hepatitis C virus were measured in fasting baseline serum from 119 incident PLCs, 157 CLD-death cases and 512 matched controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression to estimate the associations between insulin, glucose, HOMA-IR and the risk of PLC or CLD death.

RESULTS

Compared with the lowest quartile of insulin, multivariable adjusted models showed that subjects in the highest quartile had elevated odds of developing PLC (ORQ4/Q1 = 2.42, 95% CI = 1.26-4.75, Ptrend = 0.007), particularly in HBV-positive subjects (Pinteraction = 0.040), and of CLD death (ORQ4/Q1 = 1.80, 95% CI = 1.02-3.21, Ptrend = 0.018). For glucose, in the HBV-positive group, subjects in the fourth quartile had an increased risk of PLC (ORQ4/Q1 = 2.18, 95% CI = 1.07-4.60, Ptrend = 0.009), and of CLD mortality (ORQ4/Q1 = 1.75, 95% CI = 0.95-3.28, Ptrend = 0.019). Subjects with the highest HOMA-IR values had a threefold risk of developing PLC (ORQ4/Q1 = 2.94, 95% CI = 1.54-5.87, Ptrend = 0.001), and a twofold risk of CLD death (ORQ4/Q1 = 2.20, 95% CI = 1.25-3.94, Ptrend = 0.005).

CONCLUSIONS

We found that serum insulin and HOMA-IR could potentially be risk factors for PLC or CLD death.

Association of triglyceride glucose-body mass index with non-small cell lung cancer risk: A case-control study on Chinese adults

Background and objectives

Insulin resistance (IR) is closely related to non-small-cell lung cancer (NSCLC) risk. Recently, triglyceride glucose-body mass index (TyG-BMI) has been recognized as one of the simple indexes of insulin resistance (IR). However, there are limited data on the relationship between TyG-BMI and NSCLC. Here, we investigated the association of TyG-BMI with NSCLC risk in Chinese adults.

Methods

This study consisted of 477 NSCLC cases and 954 healthy subjects. All participants were enrolled from 3201 Hospital affiliated to the Medical Department of Xi'an Jiaotong University. TyG-BMI was calculated based on the values of fasting blood glucose, triglyceride, and BMI. The association of TyG-BMI with NSCLC risk was estimated by logistic regression analysis.

Results

The mean value of TyG-BMI was statistically increased in patients with NSCLC compared to the control group (201.11 ± 28.18 vs. 174 ± 23.78, P < 0.01). There was a significant positive association between TyG-BMI and NSCLC (OR = 1.014; 95% CI 1.007-1.021; P < 0.001) after controlling for confounding factors. Moreover, the prevalence of NSCLC was significantly elevated in participants in the high TyG-BMI tertiles than those in the intermediate and low TyG-BMI tertiles (60.46% vs. 12.61% vs. 26.83%, P < 0.01). Importantly, TyG-BMI achieved a significant diagnostic accuracy for NSCLC, with an AUC (area under the curve) of 0.769 and a cutoff value of 184.87.

Conclusion

The findings suggest that TyG-BMI is a useful tool for assessing NSCLC risk. Thus, it is essential to follow up on high TyG-BMI, and lifestyle modification is needed to prevent NSCLC in people with high TyG-BMI.

iTRAQ-Based Proteome Profiling of Differentially Expressed Proteins in Insulin-Resistant Human Hepatocellular Carcinoma

Recently, the incidences of insulin resistance (IR) and IR-related complications have increased throughout the world, which also associate with poor prognosis in hepatocellular carcinoma (HCC). Numerous studies had been focused on the role of IR in tumorigenesis and prognosis of HCC. The proteomic analysis of IR related hepatocellular carcinoma had not been reported by now. In the present study, 196 differentially expressed proteins (DEPs) were identified between insulin resistant HepG2 cells and their parental cells, of which 109 proteins were downregulated and 87 proteins were upregulated. Bioinformatics analysis indicated that these DEPs were highly enriched in process of tumorigenesis and tumor progression. PPI network analysis showed that SOX9, YAP1 and GSK3β as the key nodes, were involved in Wnt and Hippo signaling pathways. Survival analysis revealed that high expression of SOX9 and PRKD3 were strongly associated with reduced patient survival rate. parallel reaction monitoring (PRM) and Western blot analysis were applied to verify the protein level of these four key nodes mentioned above, which showed the same trend as quantified by isobaric tags for relative and absolute quantitation (iTRAQ) and confirmed the reliability of our Proteome Profiling analysis. Our results indicated that IR related dysregulation of protein expression might participated in tumorigenesis and malignant phenotype of hepatocarcinoma cells.

Adiposity, Adulthood Weight Change, and Risk of Incident Hepatocellular Carcinoma

Prospective data are limited regarding dynamic adulthood weight changes and hepatocellular carcinoma (HCC) risk. We included 77,238 women (1980-2012) and 48,026 men (1986-2012), who recalled young-adult weight [age 18 years (women); 21 years (men)], and provided biennially updated information regarding weight, body mass index (BMI), and comorbidities. Overall adulthood weight change was defined as the difference in weight (kilograms) between young-adulthood and present. Using Cox proportional hazards models, we calculated multivariable adjusted HRs (aHR) and 95% confidence intervals (CI). Over 3,676,549 person-years, we documented 158 incident HCC cases. Elevated HCC risk was observed with higher BMI in both young-adulthood and later-adulthood [continuous aHRs per each 1 unit = 1.05; 95% CI = 1.02-1.09 (P trend = 0.019), and 1.08; 95% CI = 1.06-1.10 (P trend = 0.004), respectively]. Moreover, overall adulthood weight gain was also significantly associated with increased HCC risk (aHR per each 1-kg increase = 1.03; 95% CI = 1.01-1.08; P trend = 0.010), including after further adjusting for young-adult BMI (P trend = 0.010) and later-adult BMI (P trend = 0.008). Compared with adults with stable weight (±5 kg), the multivariable-aHRs with weight gain of 5-<10 kg, 10-<20 kg, and ≥20 kg were, 1.40 (95% CI = 0.67-2.16), 2.09 (95% CI = 1.11-3.95), and 2.61 (95% CI = 1.42-5.22), respectively. In two prospective, nationwide cohorts, adulthood weight gain was significantly associated with increased HCC risk. PREVENTION RELEVANCE: Our data suggest that maintaining a stable weight during adulthood, specifically by preventing weight gain, could represent an important public health strategy for the prevention of hepatocellular carcinoma.

Molecular Mechanisms Linking Nonalcoholic Steatohepatitis to Cancer

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Combination treatment strategies with a focus on rosiglitazone and adriamycin for insulin resistant liver cancer

Insulin resistance promotes the occurrence of liver cancer and decreases its chemosensitivity. Rosiglitazone (ROSI), a thiazolidinedione insulin sensitiser, could be used for diabetes with insulin resistance and has been reported to show anticancer effects on human malignant cells. In this paper, we investigated the combination of ROSI and chemotherapeutics on the growth and metastasis of insulin-resistant hepatoma. In vitro assay, ROSI significantly enhanced the inhibitory effects of adriamycin (ADR) on the proliferation, autophagy and migration of insulin-resistant hepatoma HepG2/IR cells via downregulation of EGFR/ERK and AKT/mTOR signalling pathway. In addition, ROSI promoted the apoptosis of HepG2/IR cells induced by ADR. In vivo assay, high fat and glucose diet and streptozotocin (STZ) induced insulin resistance in mice by increasing the body weight, fasting blood glucose (FBG) level, oral glucose tolerance, fasting insulin level and insulin resistance index. Both the growth of mouse liver cancer hepatoma H22 cells and serum FBG level in insulin resistant mice were significantly inhibited by combination of ROSI and ADR. Thus, ROSI and ADR in combination showed a stronger anti-tumour effect in insulin resistant hepatoma cells accompanying with glucose reduction and might represent an effective therapeutic strategy for liver cancer accompanied with insulin resistant diabetes.

Lifestyle and Environmental Approaches for the Primary Prevention of Hepatocellular Carcinoma

Patients with chronic liver disease are at increased risk of developing hepatocellular carcinoma (HCC). Most patients diagnosed with HCC have limited treatment options and a poor overall prognosis, with a 5-year survival less than 15%. Preventing the development of HCC represents the most important strategy. However, current guidelines lack specific recommendations for primary prevention. Lifestyle factors may be central in the pathogenesis of HCC, and primary prevention strategies focused on lifestyle modification could represent an important approach to the prevention of HCC. Both experimental and epidemiologic studies have identified promising chemopreventive agents for the primary prevention of HCC.

SHP2 knockdown ameliorates liver insulin resistance by activating IRS-2 phosphorylation through the AKT and ERK1/2 signaling pathways

Diabetes is a chronic metabolic disease characterized by insulin resistance (IR). SHP2 has previously been identified as a potential target to reduce IR in diabetes. Here, we examined the effects of SHP2 on glucose consumption (GC), IR level and the expression of insulin receptor substrate (IRS), AKT and extracellular signal-regulated kinase (ERK)1/2 proteins in a cellular and animal model of diabetes. IR was induced in hepatocellular carcinoma (HCC) cells, and SHP2 was up-regulated or down-regulated in cells. Diabetic rats were treated with SHP2 inhibitor. GC of cells, and the weight, total cholesterol, triglycerides, fasting blood glucose, fasting insulin, homeostasis model assessment-IR index and insulin sensitivity (ISI) of the rats were analyzed. The levels of SHP2 and the activation of IRS-2, AKT and ERK1/2 in cells and rats were measured by quantitative real-time PCR (qRT-PCR) or western blot. GC was reduced, but expression of SHP2 was enhanced in IR HCC cells. Phosphorylation of IRS-2 and AKT in IR HCC cells and diabetic rats was decreased, whereas phosphorylation of ERK1/2 was enhanced. In both the cell and animal models, SHP2 knockdown enhanced GC, ameliorated IR, activated IRS-2 and AKT, and inhibited ERK1/2 phosphorylation, in contrast with the effects of SHP2 overexpression. SHP2 knockdown may enhance GC and ameliorate IR through phosphorylation of IRS-2 via regulating AKT and ERK1/2 in liver.

Exercise retards hepatocarcinogenesis in obese mice independently of weight control

BACKGROUND & AIMS

Obesity and type 2 diabetes increase hepatocellular carcinoma (HCC) incidence in humans and accelerate diethylnitrosamine (DEN)-induced hepatocarcinogenesis in mice. We investigated whether exercise reduces HCC development in obese/diabetic Alms1 mutant (foz/foz) mice and studied protective mechanisms.

METHODS

We measured HCC development in DEN-injected male foz/foz and wild-type (WT) littermates housed with or without an exercise wheel from week 4 until 12 or 24 weeks, and in foz/foz mice pair-fed to WT littermates. We also studied HCC development in DEN-injected Jnk1^-/-.foz/foz mice generated by cross breeding, as well as their genetic controls. Dysplastic hepatocytes were identified by glutathione-S-transferase pi form (GST-pi) immunohistochemistry, liver nodules were counted, and HCC was analysed by histopathology.

RESULTS

Exercising foz/foz mice maintained similar weight as WT mice up to 10 weeks, but then gained weight and were obese by 24 weeks; a similar body weight profile was obtained by pair-feeding foz/foz mice to WT. At 12 weeks, livers of exercising foz/foz mice exhibited fewer GST-pi positive hepatocytes than sedentary counterparts; by 24 weeks, fewer exercising foz/foz mice developed HCC (15% vs. 64%, p <0.05). Conversely, pair-feeding foz/foz mice failed to reduce HCC incidence. In these insulin-resistant foz/foz mice, exercise failed to activate hepatic AMPK or Akt/mTORC1. Instead, it improved insulin sensitivity, ameliorated steatosis and liver injury, activated p53 to increase p27 expression, and prevented JNK activation. This was associated with suppression of hepatocellular proliferation. DEN-injected Jnk1^-/-.foz/foz mice failed to develop liver tumours or HCC at 24 weeks.

CONCLUSIONS

Direct effects of exercise dampen proliferation of dysplastic hepatocytes to reduce 3-month dysplastic foci and 6-month incidence of DEN-induced HCC in obese, insulin-resistant mice. The effects of exercise that potentially slow hepatocarcinogenesis include p53-mediated induction of p27 and prevention of JNK activation.

LAY SUMMARY

Fatty liver disease commonly occurs alongside obesity and diabetes, contributing to rapidly increasing rates of liver cancer throughout the world. Herein, we show that exercise reduces the incidence and progression of hepatocellular carcinoma in mouse models. The effect of exercise on cancer risk was shown to be independent of changes in weight. Exercise could be a protective mechanism against liver cancer in at-risk individuals.

The Hepatoprotective Effect of Taurisolo, a Nutraceutical Enriched in Resveratrol and Polyphenols, Involves Activation of Mitochondrial Metabolism in Mice Liver

Liver diseases affect millions of people worldwide. In most of the cases, severe hepatic dysfunction and liver cancer stem from mild and common clinical signs including hepatic steatosis, insulin resistance, liver inflammation, and oxidative stress, all together referred to as Nonalcoholic Fatty Liver Disease (NAFLD). Nutraceuticals endowed with antioxidant activity have been shown to reduce NAFLD risk factors and exert hepatoprotective effects. Here, we test the protective effect exerted on liver by the antioxidant Taurisolo, a nutraceutical formulation produced by grape pomace and enriched in Resveratrol and Polyphenols. We analyze the effect of Taurisolo on liver cells by profiling the metabolome of in vitro cultured hepatic HuH7 cells and of C57BL-6J mice fed a High Fat Diet and treated with the nutraceutical. Both in vitro and in vivo, we provide evidence that Taurisolo reduces risk factor markers associated with NAFLD. Taurisolo stimulates glucose uptake and reduces hepatic cholesterol and serum triglycerides. Furthermore, we give new insights into the mechanism of action of Taurisolo. The nutraceutical increases mitochondrial activity and promotes respiration and ATP production, fostering catabolic reactions like fatty acid β-oxidation and amino acid catabolism. On the contrary, Taurisolo reduces anabolic reactions like biosynthesis of cholesterol, bile acids, and plasma membrane lipids.

Harnessing adipogenesis to prevent obesity

Obesity and associated metabolic complications, including diabetes, cardiovascular and hepatic diseases, and certain types of cancers, create a major socioeconomic burden. Obesity is characterized by excessive expansion of white adipose tissue resulting from increased adipocyte size, and enhanced adipocyte precursor cells proliferation and differentiation into mature adipocytes, a process well-defined as adipogenesis. Efforts to develop therapeutically potent strategies to circumvent obesity are impacted by our limited understanding of molecular mechanisms regulating adipogenesis. In this review, we discuss recently discovered molecular mechanisms restraining adipogenesis. In this perspective, the discoveries of white adipose tissue endogenous adipogenesis-regulatory cells (Aregs) that negatively regulate adipocyte differentiation, platelet-derived growth factor receptor isoform α (PDGFRα) activation and downstream signaling that hinder adipocyte precursors differentiation, and a group of obesity-associated non-coding RNAs (ncRNAs) that regulate adipogenesis open up promising therapeutic avenues to prevent and/or treat obesity.

Pathogenesis of hypothyroidism-induced NAFLD: Evidence for a distinct disease entity?

Nonalcoholic fatty liver disease (NAFLD), the most common liver disease worldwide, may be associated with primary hypothyroidism. However, the pathogenesis underlying such an association is complex and not completely understood. Here, we specifically discuss the pathogenic mechanisms potentially involved in hypothyroidism-induced NAFLD. To this end, we summarize the general pathophysiology of thyroid hormones (TH). Next, we analyze the published data from rodent studies by discussing whether hypothyroid rats may develop NAFLD via hyperphagia; whether mitochondria become energetically more efficient; what the overall energy balance is and if diversion of fatty substrates occurs; and the latest advancements in molecular pathogenesis brought about by metabolomics, cell imaging, lipophagy, autophagy and genetically engineered mouse models. Moreover, we discuss the data published regarding humans on the pathogenic role of TH, metabolic syndrome and other risk factors in hypothyroidism-related NAFLD as well as the putative mechanisms underlying the development of NAFLD-related hepatocellular carcinoma in hypothyroidism. In conclusion, although many research questions still remain unanswered, the pathophysiology of hypothyroidism-induced NAFLD makes this a potentially curable and distinct disease entity. However, further studies are needed to better elucidate the underlying mechanisms, and to ascertain whether treatment with either TH or thyromimetic agents improves NAFLD.

Type 2 diabetes mellitus increases the risk of hepatocellular carcinoma in subjects with chronic hepatitis B virus infection: a meta-analysis and systematic review

Background

Type 2 diabetes mellitus has been proved to be a risk factor of hepatocellular carcinoma, but how diabetes affects incidence of hepatocellular carcinoma among patients with chronic hepatitis B virus infection remains controversial.

Methods

A comprehensive search of Medline and Embase was performed. Incidence of hepatocellular carcinoma in chronic hepatitis B patients was the primary outcome. Pooled HRs and 95% CIs were calculated to assess the correlation between diabetes and incidence of hepatocellular carcinoma.

Results

Five cohort studies and two case–control studies were identified, with a total of 21,842 chronic hepatitis B patients. The diabetes mellitus cohort was found to have increased incidence of hepatocellular carcinoma (pooled HR 1.77, 95% CI 1.28–2.47; fixed effect) and worse overall mortality (pooled RR 1.93, 95% CI 1.64–2.27; fixed effect) in comparison with those without diabetes. In case–control studies, hepatocellular carcinoma cases were found to have an insignificantly elevated diabetes mellitus rate in comparison with the control group.

Conclusion

Type 2 diabetes mellitus is significantly associated with increased risk of hepatocellular carcinoma among patients with chronic hepatitis B virus infection, and aggressive management of diabetes mellitus is strongly suggested.

Effects of Diabetes and Glycemic Control on Risk of Hepatocellular Carcinoma After Seroclearance of Hepatitis B Surface Antigen

BACKGROUND & AIMS

Diabetes is associated with a 2-fold increase in risk of hepatocellular carcinoma (HCC) among patients with chronic hepatitis B virus (HBV) infection. However, we know little about the effect of diabetes on HCC risk after seroclearance of hepatitis B surface antigen (HBsAg). We evaluated the effect of diabetes and glycemic control on HCC development after HBsAg seroclearance in a population-wide study in Hong Kong.

METHODS

We performed a retrospective study of 4568 patients with chronic HBV infection who cleared HBsAg from January 2000 through August 2016, using the Clinical Data Analysis and Reporting System of the Hospital Authority, Hong Kong. We collected and analyzed data on patient demographics, comorbidities, medications, laboratory test results, and subsequent development of HCC. The presence of diabetes was defined by International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code, with level of hemoglobin A1c (HbA1c) above 6.5%, fasting glucose level of 7 mmol/L or more, or treatment with any antidiabetic agent.

RESULTS

We identified 1560 patients with diabetes; 29 patients (1.9%) developed HCC after a median follow-up time of 3.4 years (interquartile range, 1.5-5.0 years). Diabetes was associated with increased risk of HCC after adjustment of age, sex, presence of cirrhosis, and the use of medications (adjusted hazard ratio, 1.85; 95% CI, 1.04-3.28; P = .036). Among patients with diabetes, time-weighted average level of HbA1c was an independent risk factor for HCC, after adjustment for age at clearance, use of statins, and other important covariates (adjusted hazard ratio: 1.51; 95% CI, 1.20-1.91; P < .001). A time-weighted average level of HbA1c of 7% or more was associated with a higher 5-year cumulative incidence of HCC (4.0%) than a time-weighted average HbA1c level below 7% (1.8%; log-rank test P = .035).

CONCLUSIONS

In a population-based analysis of patients with chronic HBV infection in Hong Kong, we found diabetes to be an independent risk factor for HCC after HBsAg seroclearance. However, glycemia control appears to reduce the risk of HCC.

Causes and mechanisms of adipocyte enlargement and adipose expansion

Adipose tissue plays a significant role in whole body energy homeostasis. Obesity-associated diabetes, fatty liver and metabolic syndrome are closely linked to adipose stress and dysfunction. Genetic predisposition, overeating and physical inactivity influence the expansion of adipose tissues. Under conditions of constant energy surplus, adipocytes become hypertrophic and adipose tissues undergo hyperplasia so as to increase their lipid storage capacity, thereby keeping circulating blood glucose and fatty acids below toxic levels. Nonetheless, adipocytes have a saturation point where they lose capacity to store more lipids. At this stage, when adipocytes are fully lipid-engorged, they express stress signals. Adipose depots (particularly visceral compartments) from obese individuals with a severe metabolic phenotype are characterized by the high proportion of hypertrophic adipocytes. This review focuses on the mechanisms of adipocyte enlargement in relation to adipose fatty acid and cholesterol metabolism, and considers how this may be related to adipose dysfunction.

Insulin resistance and the risk of hepatocellular carcinoma in chronic hepatitis B patients

BACKGROUND AND AIM

We analyzed whether insulin resistance (IR) assessed by homeostasis model assessment (HOMA2-IR) index can stratify hepatocellular carcinoma (HCC) risk in patients with chronic hepatitis B virus (HBV) infection.

METHODS

A retrospective cohort of 1696 chronic HBV-infected patients (age: 50.0 ± 7.8 years, men = 964 [56.8%]) who underwent detailed health checkup program including C-peptide and fasting blood glucose measurement and followed up for more than a year were analyzed.

RESULTS

During a median follow-up of 5.0 years (range, 1.0-10.5 years), 24 patients (1.4%) developed HCC. The HCC incidence rate was higher for patients with higher HOMA2-IR value than those with lower HOMA2-IR value (1.7% vs 0.5% for HOMA2-IR >1.200 vs ≤1.200, P = 0.009). HOMA2-IR was a significant factor associated with HCC development in multivariable-adjusted model (HR [95% CI]: 3.25 [1.13-9.31], adjusted for age, sex, cirrhosis, and HBV DNA levels). The association between HOMA2-IR and HCC was markedly attenuated and became no longer statistically significant (HR [95% CI]: 1.93 [0.57-6.51]) when further adjusted for obesity, hypertension, and diabetes. In subgroup analysis, HOMA2-IR value was an independent factor associated with HCC in patients without overt metabolic abnormalities (hypertension, diabetes, and metabolic syndrome) but not for those with overt metabolic abnormalities.

CONCLUSION

Insulin resistance assessed by HOMA2 was associated with the risk of HCC, indicating that HOMA2-IR can be a useful tool for stratifying the risk of HCC in chronic HBV-infected patients, particularly in patients without overt metabolic abnormalities.

Incidence of Hepatocellular Carcinoma in All 50 United States, From 2000 Through 2012

BACKGROUND & AIMS

The incidence and mortality of hepatocellular carcinoma (HCC) have been reported to be plateauing in the United States. The United States has large racial, ethnic, and regional variation; we collected data from all 50 states to better analyze changes in HCC incidence in the entire United States.

METHODS

We collected data from the US Cancer Statistics registry, which covers 97% of the population, and calculated adjusted incidence rates. We assessed annual trends among sociodemographic and geographic subgroups using joinpoint analysis.

RESULTS

HCC incidence increased from 4.4/100,000 in 2000 to 6.7/100,000 in 2012, increasing by 4.5% (95% confidence interval [CI], 4.3%-4.7%) annually between 2000 and 2009, but only by 0.7% annually (95% CI, -0.2% to 1.6%) from 2010 through 2012. The average annual percentage change (AAPC) between 2000 and 2012 was higher in men (increase, 3.7%) than in women (increase, 2.7%), and highest in 55- to 59-year-old individuals (AAPC, 8.9%; 95% CI, 7.1%-10.7%) and 60- to 64-year-old individuals (AAPC, 6.4%; 95% CI, 4.7%-8.2%). By 2012, rates in Hispanics surpassed those in Asians, and rates in Texas surpassed those in Hawaii (9.71/100,000 vs 9.68/100,000). Geographic variation within individual race and ethnic groups was observed, but rates were highest in all major race and ethnic groups in Texas.

CONCLUSIONS

In an analysis of the incidence of HCC in all 50 US states, we found the rate of increase in HCC to have slowed from 2010 through 2012. However, incidence is increasing in subgroups such as men ages 55 to 64 years old-especially those born in the peak era of hepatitis C virus infection and among whites/Caucasians. Rates in Hispanics have surpassed those in Asian Americans. We observed geographic differences, with Texas having the highest age-adjusted HCC rates nationwide.

Liver fibrosis in treatment-naïve HIV-infected and HIV/HBV co-infected patients: Zambia and Switzerland compared

OBJECTIVE

To examine the association between hepatitis B virus (HBV) infection and liver fibrosis in HIV-infected patients in Zambia and Switzerland.

METHODS

HIV-infected adults starting antiretroviral therapy in two clinics in Zambia and Switzerland were included. Liver fibrosis was evaluated using the aspartate aminotransferase-to-platelet-ratio index (APRI), with a ratio >1.5 defining significant fibrosis and a ratio >2.0 indicating cirrhosis. The association between hepatitis B surface antigen (HBsAg) positivity, HBV replication, and liver fibrosis was examined using logistic regression.

RESULTS

In Zambia, 96 (13.0%) of 739 patients were HBsAg-positive compared to 93 (4.5%) of 2058 in Switzerland. HBsAg-positive patients were more likely to have significant liver fibrosis than HBsAg-negative ones: the adjusted odds ratio (aOR) was 3.25 (95% confidence interval (CI) 1.44-7.33) in Zambia and 2.50 (95% CI 1.19-5.25) in Switzerland. Patients with a high HBV viral load (≥20000 IU/ml) were more likely to have significant liver fibrosis compared to HBsAg-negative patients or patients with an undetectable viral load: aOR 3.85 (95% CI 1.29-11.44) in Zambia and 4.20 (95% CI 1.64-10.76) in Switzerland. In both settings, male sex was a strong risk factor for significant liver fibrosis.

CONCLUSIONS

Despite the differences in HBV natural history between Sub-Saharan Africa and Europe, the degree of liver fibrosis and the association with important risk factors were similar.

Insulin resistance contributes to multidrug resistance in HepG2 cells via activation of the PERK signaling pathway and upregulation of Bcl-2 and P-gp

Liver tumorigenesis frequently causes insulin resistance which may be used as an independent risk factor for evaluation of survival and post-surgery relapse of liver cancer patients. In the present study, HepG2/IR, an insulin resistant HepG2 cell line, was established by exposing HepG2 cells to 0.5 µmol/l of insulin for 72 h, and comparison of HepG2/IR with the parental HepG2 cells indicated that the HepG2/IR cells showed significantly enhanced resistance to the most frequently used chemotherapeutics for solid tumors, such as cisplatin, 5-fluorouracil, vincristine and mitomycin. Flow cytometric analysis of cisplatin-treated HepG2/IR cells showed a significantly decreased hypodiploid peak and a significantly downregulated expression level of pro-apoptotic protein caspase-3 compared with the parental HepG2 cells. Our data further showed swollen endoplasmic reticulum (ER) in the cisplatin-treated HepG2/IR cells with significantly increased levels of glucose-regulated protein 78 (GRP78), phosphorylated protein kinase R-like ER kinase (p-PERK) and P-glycoprotein (P-gp). There was also an upregulated expression of anti-apoptotic protein B-cell lymphoma 2 (Bcl-2) whereas no significant change was observed for CCAAT-enhancer-binding protein homologous protein (CHOP), which is known to be induced by ER stress and to mediate apoptosis. Our results demonstrated that insulin resistance in HepG2 cells promoted a protective unfolded protein response and upregulated the expression of ER chaperone protein GRP78, which resulted in the phosphorylation of PERK kinase to activate the PERK-mediated ER stress signal transduction pathway and the upregulation of Bcl-2 and P-gp, leading to the inhibition of the caspase-3-dependent apoptosis pathway and to the survival of liver tumor cells.

Hepatocellular Carcinoma From Epidemiology to Prevention: Translating Knowledge into Practice

The epidemiology of hepatocellular carcinoma (HCC) is characterized by dynamic temporal trends, several major established (i.e., HCV, HBV, alcohol) and emerging (i.e., diabetes, obesity, NAFLD) risk factors. Epidemiologic studies and clinical trials have identified additional demographic, clinical, pharmacological, genetic and life style factors that further affect or modify the likelihood of HCC and can be used in clinical practice to identify at-risk patients (i.e., risk stratification or prognostic algorithms) that can be targeted for prevention and early detection programs. These studies have also paved the way toward several well established preventive measures including HBV vaccination, HBV treatment, HCV treatment and HCC surveillance, and potential chemoprevention using statins, metformin or coffee. However, the effectiveness of HCC prevention in clinical practice and at the population level has lagged behind due to patient, provider, system, and societal factors. The Quality in the Continuum of Cancer Care model provides a framework for evaluating the HCC prevention processes, including potential failures that create a gap between efficacy and effectiveness.

Increased risk of hepatocellular carcinoma in chronic hepatitis C patients with new onset diabetes: a nation-wide cohort study

BACKGROUND

The impact of diabetes for hepatocellular carcinoma (HCC) development in chronic hepatitis C (CHC) patients remains controversial.

AIM

To investigate the risk of HCC in CHC patients who develop new onset diabetes.

METHODS

We conducted a nation-wide cohort study by using Taiwanese National Health Insurance Research Database, which comprised of data from >99% of entire population. Among randomly sampled one million enrollees, 6251 adult CHC patients were identified from 1997 to 2009. Diabetes was defined as new onset in the patient who was given the diagnosis in the years 1999-2009 but not in 1997-1998. The cohorts of CHC with new onset diabetes (n = 1100) and 1:1 ratio age-, gender-, and inception point (onset date of diabetes) matched nondiabetes (n = 1087) were followed up from the inception point until the development of HCC, withdrawal from insurance, or December 2009.

RESULTS

After adjustment for competing mortality, patients with new onset diabetes had a significantly higher cumulative incidence of HCC (Relative Risk = 1.544, 95% CI = 1.000-2.387, modified log-rank test, P = 0.047) as compared to those without. After adjustment for age, gender, cirrhosis, hyperlipidaemia, CHC treatment, diabetes treatment, comorbidity index, obesity and statins therapy by Cox proportional hazard model, diabetes was still an independent predictor for HCC (hazard ratio (HR) = 1.906, 95% CI = 1.102-3.295, P = 0.021). The risk for HCC was increased in those who were 40-59 years old, independent of other variables (HR = 3.086, 95% CI = 1.045-9.112, P = 0.041), and after adjustment for competing mortality (modified log-rank test, P = 0.009).

CONCLUSION

Chronic hepatitis C patients who develop diabetes are at an increased risk of hepatocellular carcinoma over time.

Increased risk of hepatocellular carcinoma in chronic hepatitis B patients with new onset diabetes: a nationwide cohort study

BACKGROUND

Diabetes increases the risk of hepatocellular carcinoma (HCC), however, the time-relationship between hepatitis B virus and diabetes for the development of HCC remains unclear.

AIM

To explore the risk of HCC in chronic hepatitis B patients with newly diagnosed diabetes.

METHODS

We conducted a nationwide cohort study by using Taiwanese National Health Insurance Research Database, which covers over 99% of entire population. Among randomly sampled one million enrollees, 14 523 chronic hepatitis B patients were diagnosed in years 1997-2009. We defined new onset diabetes as patients who were given the diagnosis in the years 1999-2009, but not in 1997-1998. The cohorts of chronic hepatitis B with new onset diabetes (n = 2099) and 1:1 ratio age-, gender- and inception point (onset date of diabetes)- matched nondiabetes (n = 2080) were followed up from the inception point until development of HCC, withdrawal from insurance or December 2009.

RESULTS

After adjustment for competing mortality, patients with new onset diabetes had a significantly higher cumulative incidence of HCC [relative risk = 1.628, 95% confidence interval (CI) = 1.114-2.378, modified log-rank test, P = 0.012] as compared to nondiabetes patients. After adjustment for age, gender, hyperlipidaemia, chronic hepatitis B treatment, statins therapy, cirrhosis, comorbidity index and obesity, diabetes was still an independent predictor for HCC (hazard ratio = 1.798, 95% CI = 1.194-2.707, P = 0.005).

CONCLUSION

Chronic hepatitis B patients with newly diagnosed diabetes have an increased risk of hepatocellular carcinoma over time.

Temporal trends of nonalcoholic fatty liver disease-related hepatocellular carcinoma in the veteran affairs population

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is a risk factor for hepatocellular carcinoma (HCC). However, no systemic studies from the United States have examined temporal trends, HCC surveillance practices, and outcomes of NAFLD-related HCC.

METHODS

We identified a national cohort of 1500 patients who developed HCC from 2005 through 2010 from Veterans Administration (VA) hospitals. We reviewed patients' full VA medical records; NAFLD was diagnosed based on histologic evidence for, or the presence of, the metabolic syndrome in the absence of hepatitis C virus (HCV) infection, hepatitis B, or alcoholic liver disease. We compared annual prevalence values for the main risk factors (NAFLD, alcohol abuse, and HCV), as well a HCC surveillance and outcomes, among HCC patients.

RESULTS

NAFLD was the underlying risk factor for HCC in 120 patients (8.0%); the annual proportion of NAFLD-related HCC remained relatively stable (7.5%-12.0%). In contrast, the proportion of HCC cases associated with HCV increased from 61.0% in 2005 (95% confidence interval, 53.1%-68.9%) to 74.9% in 2010 (95% confidence interval, 69.0%-80.7%). The proportion of HCC cases associated with only alcohol abuse decreased from 21.9% in 2005 to 15.7% in 2010, and the annual proportion of HCC cases associated with hepatitis B remained relatively stable (1.4%-3.5%). A significantly lower proportion of patients with NAFLD-related HCC had cirrhosis (58.3%) compared with patients with alcohol- or HCV-related HCC (72.4% and 85.6%, respectively; P < .05). A significantly higher percentage of patients with NAFLD-related HCC did not receive HCC surveillance in the 3 years before their HCC diagnosis, compared with patients with alcohol- or HCV-associated HCC. A lower proportion of patients with NAFLD-related HCC received HCC-specific treatment (61.5%) than patients with HCV-related HCC (77.5%; P < .01). However, the 1-year survival rate did not differ among patients with HCC related to different risk factors.

CONCLUSIONS

NAFLD is the third most common risk factor for HCC in the VA population. The proportion of NAFLD-related HCC was relatively stable from 2005 through 2010. Although patients with NAFLD-related HCC received less HCC surveillance and treatment, a similar proportion survive for 1 year, compared with patients with alcohol-related or HCV-related HCC.

Time trends of clinical characteristics in hepatocellular carcinoma patients with chronic hepatitis B virus infection: A field survey between 2000 and 2012

The hepatitis B virus (HBV) carrier rate has decreased in Japan; however, the incidence of HBV infection among hepatocellular carcinoma (HCC) patients has not decreased accordingly. In this study, we aimed to assess the time trends of the clinical characteristics in HCC patients with chronic HBV infection. Between 2000 and 2012, we enrolled a total of 156 HCC patients with chronic HBV infection in our field survey. The HCC risk was evaluated using the HCC prediction score, which is constructed from the characteristics of age, presence of liver cirrhosis and serum levels of albumin, bilirubin and HBV DNA. Lifestyle factors and the presence of diabetes mellitus were also evaluated. The time trends of patient characteristics were analyzed using the Jonckheere-Terpstra proportion trend test. Among HCC patients with chronic HBV infection, the proportion of patients at high risk according to the HCC prediction score significantly decreased during the study period (P=0.0005). Similarly, the proportion of patients with liver cirrhosis, ≤3.5 g/dl serum albumin level, >4 log copies/ml serum HBV DNA level and ≥60 g/day alcohol intake were also significantly decreased. The proportion of male and obese patients was not significantly altered, whereas the proportion of elderly (≥65 years) and diabetic patients tended to increase during the study period (P=0.0654 and P=0.0528, respectively). In this study, we analyzed the time trends of the clinical characteristics in HCC patients with chronic HBV infection and demonstrated that aging and diabetes mellitus may be involved in the hepatocarcinogenesis in patients with chronic HBV infection.

Racial differences in the progression to cirrhosis and hepatocellular carcinoma in HCV-infected veterans

OBJECTIVES

The race of patients infected with hepatitis C virus (HCV) in the United States may be associated with the risk for cirrhosis and hepatocellular carcinoma (HCC). However, previous studies are too small to provide convincing data regarding the effect of race on cirrhosis and HCC risk after accounting for demographic, clinical, and virological factors.

METHODS

We used the Veterans Administration (VA) HCV Clinical Case Registry to identify patients with confirmed viremia between 2000 and 2009 and with at least 1 year of follow-up in the VA. We identified cirrhosis and HCC cases through early 2010. Cox proportional hazard regression models were performed to examine the effect of race on the risk for cirrhosis and HCC while adjusting for patients' age, gender, period of service (World War I/II, Vietnam era, post-Vietnam era), HIV coinfection, HBV coinfection, alcohol abuse, diabetes, body mass index, and antiviral treatment receipt and response.

RESULTS

There were 149,407 patients with active HCV viremia. Of them, 56.3% were non-Hispanic White (NHW), 36.1% were African American (AA), 6.0% were Hispanic, and 1.6% belonged to other racial groups. After an average follow-up of 5.2 years, 13,099 patients were seen to have a recorded diagnosis of cirrhosis and 3,551 had HCC. Hispanics had the highest annual incidence rates of cirrhosis and HCC (28.8 and 7.8%, respectively), whereas AAs had the lowest rates (13.3% and 3.9%, respectively) compared with NHWs (21.6 and 4.7%, respectively). There were differences among NHW, AA, and Hispanic patients in the rates of HIV infection (2.1, 2.5, and 6.0%, respectively), HCV genotype 1 (50.0, 50.6, and 64.2%, respectively), obesity (28.0, 25.4, and 30.9%, respectively), diabetes (8.7, 16.1, and 16.1%, respectively), and absence of antiviral treatment (81.1, 89.6, and 82.1%, respectively). However, adjusting for differences in demographic and clinical factors did not change the magnitude or direction of the race effect. Compared with NHWs, Hispanic patients had a higher risk of having cirrhosis recorded (adjusted hazard ratio (HR)=1.28, 95% confidence interval (CI)=1.21-1.37) and HCC (1.61, 95% CI=1.44-1.80). In contrast, AAs had a lower risk of cirrhosis (HR=0.58, 95% CI=0.55-0.60) and HCC (0.77, 95% CI=0.71-0.83) compared with NHWs.

CONCLUSIONS

Hispanics with HCV are at a significantly higher risk, whereas AAs are at a considerably lower risk of developing cirrhosis and HCC than are NHWs. These associations persisted even after adjusting for a range of factors including HCV genotype, HCV treatment, diabetes, and body mass index.

Animal models are reliably mimicking human diseases? A morphological study that compares animal with human NAFLD

Non-alcoholic fatty liver disease (NAFLD) is a clinical-pathological syndrome that includes a wide spectrum of morphological alterations. In research, animal models are crucial in evaluating not only the pathogenesis of NAFLD and its progression, but also the therapeutic effects of various agents. Investigations on the ultrastructural features of NAFLD in humans are not copious, due to the difficulty to obtain human samples and to the long time of NAFLD to evolve. Translational comparative studies on the reliability of animal models in representing the histopathologic picture as seen in humans are missing. To overcome this lack of investigations, we compared the ultrastructural NAFLD features of an animal model versus human. Sprague-Dawley rats were fed with a high fat diet (HFD) for 1-4 weeks, while control rats were fed with a standard diet. Human specimens were collected from patients with diagnosed fatty liver disease, undergoing liver biopsies or surgery. Rat and human samples were examined by light microscopy and by transmission and high resolution scanning electron microscopy. The present work demonstrated that NAFLD in animal model and in human, share overlapping ultrastructural features. In conclusion, animal HFD represent an appropriate tool in studying the pathogenesis of NAFLD.