Effect of physiologic hyperinsulinemia on glucose and lipid metabolism in cirrhosis

Patients with chronic liver diseases are at risk for diabetes even before development of cirrhosis

BACKGROUND AND AIMS

The prevalence of insulin resistance (IR) and type 2 diabetes mellitus (T2DM) is higher in patients with cirrhosis, compared to control patients without liver disease. The exact mechanism for this is unknown but could include liver inflammation. In this study we investigate whether cirrhosis is the primum movens of IR or if impaired insulin sensitivity is already present in non-cirrhotic patients with chronic liver diseases.

METHODS

Patients were recruited and divided into three groups: control (CTL), chronic liver disease without cirrhosis (CLD) and cirrhosis (CIR). In patients not taking pharmacological treatment for T2DM, IR was quantified using the homeostasis model assessment of insulin resistance (HOMA-IR). The proportion of patients with T2DM as well as HOMA-IR levels among different disease etiologies were recorded and compared.

RESULTS

532 patients were included in our study. Median glycemia and insulinemia and therefore HOMA-IR values were significantly different between the three cohorts (p-value <0.001): IR levels in CLD subjects lie between those seen in CTL and CIR subjects. The proportion of diabetic patients in the two case categories also differs (p-value = 0.027): one quarter of CLD subjects and one third of CIR patients suffer from T2DM. Finally, HOMA-IR levels vary according to disease etiology (p-value <0.001): metabolic steatosis and chronic viral hepatitis C are at greater risk than alcohol and other disease causes.

CONCLUSION

CLD is already a predisposing factor to T2DM, regardless of the presence of CIR. CIR is a factor which elicits additional increase in insulin levels. Metabolic steatosis and hepatitis C are associated with more severe IR.

Glucose turnover at whole-body and skeletal muscle level in response to parenteral nutrition in male patients with alcoholic liver cirrhosis

BACKGROUND & AIMS

Cirrhosis is associated with insulin resistance and impaired glucose tolerance, which may be caused by impairments at different tissue levels (liver, skeletal muscle, and/or beta cell).

METHODS

Here, glucose kinetics at whole-body and skeletal muscle level in patients with cirrhosis (Child-Pugh A and B) were studied during parenteral nutrition using the isotope dilution technique and arteriovenous balance approach across the leg. As opposed to the euglycemic hyperinsulinemic clamp or glucose tolerance tests applied in previous studies, this approach provides a nutrient composition more similar to a normal meal while circumventing any possible portal-systemic shunting, impaired hepatic uptake and incretin effect.

RESULTS

We confirmed the presence of hepatic and peripheral insulin resistance in our patient population. Endogenous glucose production was less suppressed in response to parenteral nutrition. However, glucose uptake in skeletal muscle was increased.

CONCLUSION

Our results suggests that in our study participants with cirrhosis, the hepatic and peripheral insulin resistance is compensated for by increased insulin secretion and thus, increased glucose uptake in muscle. Hereby, glucose homeostasis is maintained.

Diabetes and cirrhosis: Current concepts on diagnosis and management

Type 2 diabetes mellitus is often associated with cirrhosis as comorbidities, acute illness, medications, and other conditions profoundly alter glucose metabolism. Both conditions are closely related in NAFLD, the leading cause of chronic liver disease, and given its rising burden worldwide, management of type 2 diabetes mellitus in cirrhosis will be an increasingly common dilemma. Having diabetes increases cirrhosis-related complications, including HCC as well as overall mortality. In the absence of effective treatments for cirrhosis, patients with type 2 diabetes mellitus should be systematically screened as early as possible for NAFLD-related fibrosis/cirrhosis using noninvasive tools, starting with a FIB-4 index followed by transient elastography, if available. In people with cirrhosis, an early diagnosis of diabetes is critical for an optimal management strategy (ie, nutritional goals, and glycemic targets). Diagnosis of diabetes may be missed if based on A1C in patients with cirrhosis and impaired liver function (Child-Pugh B-C) as anemia may turn the test unreliable. Clinicians must also become aware of their high risk of hypoglycemia, especially in decompensated cirrhosis where insulin is the only therapy. Care should be within multidisciplinary teams (nutritionists, obesity management teams, endocrinologists, hepatologists, and others) and take advantage of novel glucose-monitoring devices. Clinicians should become familiar with the safety and efficacy of diabetes medications for patients with advanced fibrosis and compensated cirrhosis. Management is conditioned by whether the patient has either compensated or decompensated cirrhosis. This review gives an update on the complex relationship between cirrhosis and type 2 diabetes mellitus, with a focus on its diagnosis and treatment, and highlights knowledge gaps and future directions.

Effects of late evening snacks on glucose homeostasis in cirrhotic patients: A meta-analysis

BACKGROUND

Insulin resistance and hepatogenic diabetes are common complications in patients with liver cirrhosis. Previous studies have shown that reducing the fasting phase by supplying a late evening snack (LES) is a potential intervention to improve substrate utilization and liver function. However, the underlying mechanisms need to be further elucidated. The purpose of current meta-analysis is to evaluate effects of LES on glucose homeostasis in cirrhotic patients.

METHODS

Electronic databases including PubMed, Web of Science, and major scientific conference sessions were searched without language restriction and carried out on March 1, 2022 with an additional manual search of bibliographies of relevant articles. A total of 4145 studies were identified, and 10 studies were eligible for the meta-analysis, comprising 631 patients (319 in the LES group and 312 in the non-LES group). Subgroup analyses were performed to investigate the effect of LES on cirrhotic patients with or without diabetes.

RESULTS

Analysis showed that LES intervention had significant effects in cirrhotic patients for glycemic parameters on fasting plasma glucose, fasting insulin, and glycosylated hemoglobin respective effect sizes of -8.7, -0.86, and -0.76. Subgroup result revealed that the effect of LES on fasting plasma glucose is higher in cirrhotic patients with diabetes group than cirrhotic patients without diabetes group, and long-term LES supplementation (>2 months) was more beneficial to maintain glucose homeostasis in cirrhotic patients than that of short-term supplementation (<2 months). LES also had significant effect on nutritional metabolic parameters like including albumin and non-protein respiratory quotient.

CONCLUSION

Meta-analysis indicated that LES not only improved malnutrition in cirrhotic patients with or without diabetes but also maintain glucose homeostasis in cirrhotic patients with diabetes. LES is a promising and simple intervention that beneficial to maintain glucose homeostasis in cirrhotic patients.

Sarcopenia in Chronic Liver Disease: A Metabolic Perspective

Sarcopenia, a condition of low muscle mass, quality, and strength, is commonly found in patients with chronic liver disease (CLD) and is associated with adverse clinical outcomes including reduction in quality of life, increased mortality, and complications. A major contributor to sarcopenia in CLD is the imbalance in muscle protein turnover wherein changes in various metabolic factors such as hyperammonemia, amino acid deprivation, hormonal imbalance, gut dysbiosis, insulin resistance, chronic inflammation, etc. have important roles. In particular, hyperammonemia is a key mediator of the liver-gut axis and is known to contribute to sarcopenia by various mechanisms including increased expression of myostatin, increased phosphorylation of eukaryotic initiation factor 2a, cataplerosis of α-ketoglutarate, mitochondrial dysfunction, increased reactive oxygen species that decrease protein synthesis and increased autophagy-mediated proteolysis. Skeletal muscle is a major organ of insulin-induced glucose metabolism, and sarcopenia is closely linked to insulin resistance and metabolic syndrome. Patients with liver cirrhosis are in a hypermetabolic state that is associated with catabolism and depletion of amino acids, particularly branched-chain amino acids. Sarcopenia can have significant implications for nonalcoholic fatty liver disease, the most common form of CLD worldwide, because of the close link between metabolic syndrome and sarcopenia. This review discusses the potential metabolic derangement as a cause or effect of sarcopenia in CLD, as well as interorgan crosstalk, which that might help identifying a novel therapeutic strategies.

Hepatogenous diabetes: Knowledge, evidence, and skepticism

The diabetogenic potential of liver cirrhosis (LC) has been known for a long time, and the name "hepatogenous diabetes" (HD) was coined in 1906 to define the condition. Diabetes mellitus (DM) that develops as a consequence of LC is referred to as HD. In patients with LC, the prevalence rates of HD have been reported to vary from 21% to 57%. The pathophysiological basis of HD seems to involve insulin resistance (IR) and pancreatic β-cell dysfunction. The neurohormonal changes, endotoxemia, and chronic inflammation of LC initially create IR; however, the toxic effects eventually lead to β-cell dysfunction, which marks the transition from impaired glucose tolerance to HD. In addition, a number of factors, including sarcopenia, sarcopenic obesity, gut dysbiosis, and hyperammonemia, have recently been linked to impaired glucose metabolism in LC. DM is associated with complications and poor outcomes in patients with LC, although the individual impact of each type 2 DM and HD is unknown due to a lack of categorization of diabetes in most published research. In fact, there is much skepticism within scientific organizations over the recognition of HD as a separate disease and a consequence of LC. Currently, T2DM and HD are being treated in a similar manner although no standardized guidelines are available. The different pathophysiological basis of HD may have an impact on treatment options. This review article discusses the existence of HD as a distinct entity with high prevalence rates, a strong pathophysiological basis, clinical and therapeutic implications, as well as widespread skepticism and knowledge gaps.

Impact of protocatechuic acid on high fat diet-induced metabolic syndrome sequelae in rats

The study aimed to assess the possible protective impact of protocatechuic acid (PCA) on high fat diet (HFD)-induced metabolic syndrome (Mets) sequelae in rats. Forty-two male Sprague-Dawley (SD) rats were randomly grouped as follows: CTR group; PCA group; HFD group; HFD-PCA group and HFD-MET group. Rats were fed on standard diet or HFD for 14 weeks. HFD-fed rats exhibited significant decreases in food intake and adiponectin (ADP) level; yet, body weight and anthropometrical parameters were significantly increased. Moreover, insulin sensitivity was impaired as indicated by significant elevation in glucose AUC during oral glucose tolerance test (OGTT), fasting serum glucose, fasting serum insulin and homeostasis model assessment of insulin resistance (HOMA-IR) index. Furthermore, chronic HFD feeding elicited significant increases in serum lipid profile and free fatty acids (FFAs) with concomitant hepatic steatosis. Additionally, serum C-reactive protein (CRP), interleukin 1b (Il-1b) and monocyte chemoattractant protein 1(MCP-1) levels were increased. Also, HFD-fed rats exhibited an increase in MDA level, while superoxide dismutase (SOD) and glutathione (GSH) activities were decreased. Moreover, the insulin-signaling pathway was markedly impaired in soleus muscles as indicated by a decrease in insulin-induced AKT phosphorylation. Histopathologically, adipose tissues showed significant increase in adipocyte size. Also, flow cytometry analysis of adipose tissue confirmed a significant increase in the percentage of number of CD68+ cells. PCA administration succeeded to attenuate HFD-induced obesity, insulin resistance, oxidative stress and inflammation. In conclusion, PCA administration could protect against HFD-induced Mets, possibly via its hypoglycemic, insulin-sensitizing, anti-oxidant and anti-inflammatory effects.

Hepatogenous Diabetes: A Primer

As liver is one of the primary organs involved in glucose homeostasis, it is not surprising that patients with liver dysfunction in chronic liver disease usually develop impaired glucose tolerance and subsequently overt diabetes later in their natural course. Diabetes that develops after the onset of cirrhosis of liver is usually referred to as hepatogenous diabetes (HD). It is an underrecognized and a hallmark endocrinological event in chronic liver disease. HD is associated with a higher risk of developing hepatic decompensations, such as ascites, variceal bleeding, hepatic encephalopathy, renal dysfunction, refractory ascites, and hepatocellular carcinoma along with reduced survival rates than normoglycemic patients with cirrhosis of liver. It is quite different from type 2 diabetes mellitus with the absence of classical risk factors, dissimilar laboratory profiles, and decreased incidence of microvascular complications. Furthermore, the management of patients with HD is challenging because of altered pharmacokinetics of most antidiabetic drugs and increased risk of hypoglycemia and other adverse effects. Hence, a clear understanding of the epidemiology, pathophysiology, clinical implications, laboratory diagnosis, and management of HD is essential for both hepatologists as well as endocrinologists, which is narrated briefly in this review.

C-peptide enhances glucagon secretion in response to hyperinsulinemia under euglycemic and hypoglycemic conditions

Several studies have associated the presence of residual insulin secretion capability (also referred to as being C-peptide positive) with lower risk of insulin-induced hypoglycemia in patients with type 1 diabetes (T1D), although the reason is unclear. We tested the hypothesis that C-peptide infusion would enhance glucagon secretion in response to hyperinsulinemia during euglycemic and hypoglycemic conditions in dogs (5 male/4 female). After a 2-hour basal period, an intravenous (IV) infusion of insulin was started, and dextrose was infused to maintain euglycemia for 2 hours. At the same time, an IV infusion of either saline (SAL) or C-peptide (CPEP) was started. After this euglycemic period, the insulin and SAL/CPEP infusions were continued for another 2 hours, but the glucose was allowed to fall to approximately 50 mg/dL. In response to euglycemic-hyperinsulinemia, glucagon secretion decreased in SAL but remained unchanged from the basal period in CPEP condition. During hypoglycemia, glucagon secretion in CPEP was 2 times higher than SAL, and this increased net hepatic glucose output and reduced the amount of exogenous glucose required to maintain glycemia. These data suggest that the presence of C-peptide during IV insulin infusion can preserve glucagon secretion during euglycemia and enhance it during hypoglycemia, which could explain why T1D patients with residual insulin secretion are less susceptible to hypoglycemia.

Insulin Resistance across the Spectrum of Nonalcoholic Fatty Liver Disease

Insulin resistance (IR) is defined as a lower-than-expected response to insulin action from target tissues, leading to the development of type 2 diabetes through the impairment of both glucose and lipid metabolism. IR is a common condition in subjects with nonalcoholic fatty liver disease (NAFLD) and is considered one of the main factors involved in the pathogenesis of nonalcoholic steatohepatitis (NASH) and in the progression of liver disease. The liver, the adipose tissue and the skeletal muscle are major contributors for the development and worsening of IR. In this review, we discuss the sites and mechanisms of insulin action and the IR-related impairment along the spectrum of NAFLD, from simple steatosis to progressive NASH and cirrhosis.

Mechanisms of Post-Pancreatitis Diabetes Mellitus and Cystic Fibrosis-Related Diabetes: A Review of Preclinical Studies

Anatomical proximity and functional correlations between the exocrine and endocrine pancreas warrant reciprocal effects between the two parts. Inflammatory diseases of the exocrine pancreas, such as acute or chronic pancreatitis, or the presence of cystic fibrosis disrupt endocrine function, resulting in diabetes of the exocrine pancreas. Although novel mechanisms are being increasingly identified, the intra- and intercellular pathways regulating exocrine-endocrine interactions are still not fully understood, making the development of new and more effective therapies difficult. Therefore, this review sought to accumulate current knowledge regarding the pathogenesis of diabetes in acute and chronic pancreatitis, as well as cystic fibrosis.

Cirrhosis and insulin resistance: current knowledge, pathophysiological mechanisms, complications and potential treatments

End-stage chronic liver diseases are often associated with insulin resistance (IR) and diabetes mellitus (DM). Indeed, to quantify insulin sensitivity the euglycemic clamp technique was utilized, allowing the following to be stated: in small groups of patients, an IR in almost all cirrhotic patients can be observed, compared with a control group. Additionally, it has been demonstrated that IR in cirrhosis is linked to a decreased peripheral (muscle) glucose uptake rather than an increased liver glucose production. The homoeostasis model of IR (HOMA-IR) technique, devised only later, was then exploited to assess this same phenomenon in a larger sample population. The research established that even in patients with preserved liver function, cirrhosis is associated with significant alterations in glucose homoeostasis levels. The purpose of the present paper is to present the current research around the affiliation of cirrhosis and IR, discuss potential mechanisms explaining the association between cirrhosis and IR (i.e. endocrine perturbation, liver inflammation, altered muscle mass and composition, altered gut microbiota and permeability), complications that can arise as well as treatment options, through a critical review of the literature surrounding this subject. This research will also be investigating the beneficial impact, if there is any, of identifying and curing IR in patients with cirrhosis.

Malnutrition in cirrhosis: More food for thought

Malnutrition is highly prevalent in liver cirrhosis and its presence carries important prognostic implications. The clinical conditions and pathophysiological mechanisms that cause malnutrition in cirrhosis are multiple and interrelated. Anorexia and liver decompensation symptoms lead to poor dietary intake; metabolic changes characterised by elevated energy expenditure, reduced glycogen storage, an accelerated starvation response and protein catabolism result in muscle and fat wasting; and, malabsorption renders the cirrhotic patient unable to fully absorb or utilise food that has been consumed. Malnutrition is therefore a considerable challenge to manage effectively, particularly as liver disease progresses. A high energy, high protein diet is recognised as standard of care, yet patients struggle to follow this recommendation and there is limited evidence to guide malnutrition interventions in cirrhosis and liver transplantation. In this review, we seek to detail the factors which contribute to poor nutritional status in liver disease, and highlight complexities far greater than "poor appetite" or "reduced oral intake" leading to malnutrition. We also discuss management strategies to optimise nutritional status in this patient group, which target the inter-related mechanisms unique to advanced liver disease. Finally, future research requirements are suggested, to develop effective treatments for one of the most common and debilitating complications afflicting cirrhotic patients.

Prevalence of diabetes in liver cirrhosis: A systematic review and meta-analysis

An association between diabetes mellitus (DM) and liver cirrhosis is well-known, but estimates of the prevalence of DM in patients with liver cirrhosis vary widely. A systematic review was undertaken to determine the prevalence of DM in adult patients with liver cirrhosis. The Medline, EMBASE, and Cochrane Library databases were searched for peer-reviewed studies published in English (1979-2017) that investigated the prevalence of diabetes in adult patients with cirrhosis. Pooled estimates of prevalence of DM were determined for all eligible patients and according to aetiology and severity of liver disease. Fifty-eight studies satisfied criteria for inclusion, with 9705 patients included in the pooled prevalence analysis. The overall prevalence of DM was 31%. The prevalence of DM was highest in patients with nonalcoholic fatty liver disease (56%), cryptogenic (51%), hepatitis C (32%), or alcoholic (27%) cirrhosis. For assessing prevalence of DM as a function of severity of liver disease, evaluable data were available only for hepatitis C and hepatitis B cirrhosis. DM may be more prevalent in cirrhosis than previously thought. This has implications for prognosis and treatment in these patients.

Nadolol reduces insulin sensitivity in liver cirrhosis: a randomized double-blind crossover trial

BACKGROUND

Liver cirrhosis is frequently complicated by portal hypertension leading to increased mortality from variceal bleeding and hepatic decompensation. Noncardioselective β-blockers not only reduce portal hypertension and prevent variceal bleeding in cirrhosis but also impair glucose tolerance and insulin sensitivity in other settings. This study aimed to determine whether nonselective β-blockade with nadolol impairs glucose metabolism in liver cirrhosis.

METHODS

A randomized, double-blind, placebo-controlled crossover trial of nadolol in cirrhotic patients examined insulin sensitivity, disposition index, and glucose tolerance. Stable cirrhotic patients of mixed etiology underwent an intravenous glucose tolerance test and hyperinsulinemic-euglycemic clamp for the measurement of insulin secretion and insulin sensitivity (n = 16) and a 75-g oral glucose tolerance test (n = 17). These measurements were conducted twice (after 3 months of treatment with nadolol or placebo and, after a 1-month washout period, after 3 months on the alternative treatment). Total body fat and plasma catecholamines were measured at the end of each 3-month treatment.

RESULTS

Compared with placebo, nadolol treatment reduced insulin sensitivity (79.7 ± 10.1 vs 99.6 ± 10.3 μL/kg fat-free mass·min^-1 ·(mU/L)^-1 , P = .005). Insulin secretion was unchanged (P = .24), yielding a lower disposition index with nadolol (6083 ± 2007 vs 8692 ± 2036, P = .050). There was no change in total body fat or plasma catecholamines. A 2-hour plasma glucose concentration from the oral glucose tolerance test was higher on nadolol than placebo (10.8 ± 0.9 vs 9.9 ± 0.9 mmol/L, P = .035).

CONCLUSIONS

Nadolol significantly worsened insulin sensitivity, glycemia, and disposition index in patients with liver cirrhosis. These findings may have significant clinical implications because cirrhosis is already associated with an increased prevalence of diabetes.

Verification of glycemic profiles using continuous glucose monitoring: cases with steroid use, liver cirrhosis, enteral nutrition, or late dumping syndrome

Glycemic control is often difficult to achieve in patients with diabetes, especially in the presence of comorbid diseases or conditions such as steroid-use or liver cirrhosis, or in patients receiving enteral nutrition. Moreover, reactive hypoglycemia due to late dumping syndrome in people having undergone gastrectomy is also a matter of concern. Empirically and theoretically, the typical glycemic profiles associated with these conditions have been determined; however, what actually happens during a 24-h span is still somewhat obscure. In order to verify and provide information about the 24-h glycemic profiles associated with these conditions, 8 patients with the 4 above-mentioned conditions were monitored using a continuous glucose monitoring system (CGMS). For all 8 patients, CGMS provided detailed information regarding the 24-h glycemic profiles. The CGM results showed typical glycemic patterns for each condition, and we were moreover able to observe the effects of various practical treatments. Based on these cases, we conclude that the CGMS is highly useful for determining the glycemic patterns of patients with the aforementioned conditions in a practical setting; and this system may be used to monitor the treatment success of such cases.

Nonalcoholic fatty liver disease: cause or consequence of type 2 diabetes?

Growing epidemiological evidence suggests that nonalcoholic fatty liver disease (NAFLD) is an early predictor of and determinant for the development of type 2 diabetes and other features of the metabolic syndrome. This finding may have important clinical implications for the diagnosis, prevention and treatment of type 2 diabetes and its chronic complications. However, given the complex and bi-directional relationships between NAFLD, insulin resistance and chronic hyperglycaemia, it is extremely difficult to distinguish whether NAFLD is a cause or a consequence of insulin resistance and type 2 diabetes. Indeed, at the molecular level, hepatic lipogenesis and hepatic glucose production depend on differentially regulated branches of the insulin signalling pathway. Furthermore, genetic studies suggest that excess hepatic fat is associated with progressive liver disease, but does not always increase the risk of incident type 2 diabetes. Here, we will briefly review the epidemiological, pathophysiological and molecular evidence linking NAFLD to the development of type 2 diabetes. We will also discuss some recent genetic and therapeutic advances that seem to challenge a causal role of NAFLD in the pathogenesis type 2 diabetes, and propose a working hypothesis to explain this apparent conundrum. In conclusion, progressive liver disease and type 2 diabetes are divergent though inter-related consequences of insulin resistance and the metabolic syndrome.

Hepatogenous diabetes: Is it a neglected condition in chronic liver disease?

Diabetes mellitus (DM) that occurs because of chronic liver disease (CLD) is known as hepatogenous diabetes (HD). Although the association of diabetes and liver cirrhosis was described forty years ago, it was scarcely studied for long time. Patients suffering from this condition have low frequency of risk factors of type 2 DM. Its incidence is higher in CLD of viral, alcoholic and cryptogenic etiology. Its pathophysiology relates to liver damage, pancreatic dysfunction, interactions between hepatitis C virus (HCV) and glucose metabolism mechanisms and genetic susceptibility. It associates with increased rate of liver complications and hepatocellular carcinoma, and decreased 5-year survival rate. It reduces sustained virological response in HCV infected patients. In spite of these evidences, the American Diabetes Association does not recognize HD. In addition, the impact of glucose control on clinical outcomes of patients has not been evaluated. Treatment of diabetes may be difficult due to liver insufficiency and hepatotoxicity of antidiabetic drugs. Notwithstanding, no therapeutic guidelines have been implemented up to date. In this editorial, authors discuss the reasons why they think that HD may be a neglected pathological condition and call attention to the necessity for more clinical research on different fields of this disease.

Current Concepts in Diabetes Mellitus and Chronic Liver Disease: Clinical Outcomes, Hepatitis C Virus Association, and Therapy

Hereditary type 2 diabetes mellitus is a risk factor for chronic liver disease, and ~30 % of patients with liver cirrhosis develop diabetes. Diabetes mellitus has been associated with cirrhotic and non-cirrhotic hepatitis C virus liver infection, can aggravate the course the liver infection, and can induce a lower sustained response to antiviral treatment. Evidences that HCV may induce metabolic and autoimmune disturbances leading to hypobetalipoproteinemia, steatosis, insulin resistance, impaired glucose tolerance, thyroid disease, and gonadal dysfunction have been found. Prospective studies have demonstrated that diabetes increases the risk of liver complications and death in patients with cirrhosis. However, treatment of diabetes in these patients is complex, as antidiabetic drugs can promote hypoglycemia and lactic acidosis. There have been few therapeutic studies evaluating antidiabetic treatments in patients with liver cirrhosis published to date; thus, the optimal treatment for diabetes and the impact of treatment on morbidity and mortality are not clearly known. As numbers of patients with chronic liver disease and diabetes mellitus are increasing, largely because of the global epidemics of obesity and nonalcoholic fatty liver disease, evaluation of treatment options is becoming more important. This review discusses new concepts on hepatogenous diabetes, the diabetes mellitus–hepatitis C virus association, and clinical implications of diabetes mellitus in patients with chronic liver disease. In addition, the effectiveness and safety of old and new antidiabetic drugs, including incretin-based therapies, will be described.

Alterations in carbohydrate metabolism in cirrhotic patients before and after liver transplant

AIM

The main objective of this study is to demonstrate whether carbohydrate metabolism alterations identified in patients with advanced cirrhosis show any improvement after liver transplant.

METHODS

The study included 86 patients who underwent liver transplant between March 2010 and February 2011. An oral glucose tolerance test was performed before the liver transplant, and 6 and 12 months after. Beta cell function and insulin resistance were also calculated, applying formulae that use basal plasma glycaemia and insulin, and plasma glycaemia and insulin during an oral glucose tolerance test. Risk factors for pre- and post-transplant diabetes were also studied. The diagnosis of diabetes was based on an OGTT.

RESULTS

The proportion of patients with diabetes before transplant, and at month 6 and 12 after transplant were 70.9%, 48.8% and 39.2%, respectively. Compared to baseline, at month 6 the odds ratio of having diabetes was 0.39 (IC 95% [0.21, 0.73]) and at month 12 it was 0.26 (IC 95% [0.14, 0.50]). The composite insulin sensitivity index values at 6 and 12 months were 1.72 units higher (IC 95% [0.84, 2.58]) and 1.58 units higher (IC 95% [0.68, 2.44)] than baseline. A statistically significant association was found between high MELD values and high body mass index, and risk of pre-transplant diabetes (p=0.001 and p=0.033, respectively). Cirrhosis aetiology did not influence the risk of diabetes.

CONCLUSIONS

In this study, we were able to ascertain that alterations in carbohydrate metabolism typical of advanced cirrhosis improve after liver transplant. This improvement is mainly due to an improvement in insulin resistance.

Plasma betatrophin levels in patients with liver cirrhosis

AIM: To investigate the plasma levels of betatrophin in patients with cirrhosis.

METHODS: Forty patients diagnosed at the clinic with liver cirrhosis according to biological, ultrasonographic, or histological criteria were included. The severity of cirrhosis was classified according to Pugh’s modification of Child’s classification and MELD score. Insulin resistance (IR) was assessed by the Homeostasis Model Assessment. A total of 20 patients showed a MELD score higher than 14. The control group consisted in 15 sex-and aged-matched subjects. Fasting blood samples were obtained for subsequent analysis. Serum insulin was determined by Liaison automated immune chemiluminiscence assay (DiaSorin S.p.A.) using a sandwich assay. The sensitivity of the assay was 0.2 μU/mL. The intra and interassay variation coefficients were < 4% and < 10%, respectively. The normal values were between 2 and 17 μU/mL. Human active betatrophin was analyzed by specific quantitative sandwich ELISA (Aviscera Bioscience^®). The sensitivity of the assay was 0.4 ng/mL, and the intra and interassay reproducibility were < 6% and < 10%, respectively.

RESULTS: Plasma betatrophin levels were significantly increased in patients with cirrhosis compared with those in healthy subjects (P = 0.0001). Betatrophin levels were also associated with disease severity, being higher in Child-Pugh C patients compared to Child-Pugh B (P < 0.0005) and in patients who displayed a MELD score higher than 14 points compared to patients with lower punctuation (P = 0.01). In addition, we found a positive correlation between plasma betatrophin levels and the severity of cirrhosis according to Child-Pugh classification (r = 0.53; P < 0.01) or MELD score (r = 0.45; P < 0.01). In the overall cohort, a moderate correlation between serum betatrophin and plasmatic bilirrubin (r = 0.39; P < 0.01) has been observed, as well as an inverse correlation between betatrophin and albumin (r = -0.41; P < 0.01) or prothrombin time (r = -0.44; P <0.01). Moreover, insulin resistance was observed in 82.5% of the cirrhotic patients. In this group of patients, betatrophin levels were significantly higher than those in the group of patients without IR (P < 0.05).

CONCLUSION: Plasma betatrophin is increased in patients with cirrhosis. This increase is related to the severity of cirrhosis, as well as with the emergence of insulin resistance.

Protein restriction in hepatic encephalopathy is appropriate for selected patients: a point of view

Since the late nineteenth century, protein restriction has been shown to improve hepatic encephalopathy. However, malnutrition has been described in up to 60 % of cirrhotic patients and is associated with increased mortality. Furthermore, emerging clinical evidence has revealed that a large proportion of cirrhotic patients may tolerate normal protein intake. However, approximately one third of cirrhotic patients with hepatic encephalopathy may need a short course of protein restriction, in addition to maximum medical therapy, to ameliorate the clinical course of their hepatic encephalopathy. For patients with chronic hepatic encephalopathy who are protein-sensitive, modifying their sources of nitrogen by using more vegetable protein, less animal protein, and branched-chain amino acids may improve their encephalopathy without further loss of lean body mass. In conclusion, among cirrhotics with hepatic encephalopathy, modulation of normal protein intake must take into account the patient's hepatic reserve, severity of hepatic encephalopathy, and current nutritional status.

Insulin resistance as early sign of hepatic dysfunction in liver cirrhosis

Glucose intolerance characterized by postprandial hyperglycemia and hyperinsulinemia is commonly seen in patients with liver cirrhosis (LC). The aim of this study is to clarify the relation between glucose intolerance and disorder of liver function in patients with LC. The 75 g oral glucose tolerance test (75 g OGTT) and the hyperinsulinemic euglycemic clamp combined with 0.2 g/kg oral glucose load (HECGL) were conducted in 61 patients with LC. Based on the results of 75 g OGTT, the 61 patients with LC were divided into groups, 21 (34.4%) patients with normal glucose tolerance (LC-NGT), 12 (19.7%) patients with impaired glucose tolerance (LC-IGT) and 28 (45.9%) patients with diabetes mellitus (LC-DM). Fasting plasma glucose (FPG) level was normal in 50 (82.0%) patients with LC. All patients with LC showed insulin resistance in both peripheral (skeletal and adipose) and hepatic tissues evaluated by HECGL, although significant correlation between the degree of glucose intolerance and the severity of hepatic dysfunction was not observed. Insulin resistance in both liver and peripheral tissues is the early sign in the patients with LC. This fact indicates that nutritional care from early stages of LC would be necessary in the patients.

Four pediatric patients with autosomal recessive polycystic kidney disease developed new-onset diabetes after renal transplantation

NODAT is increasingly prevalent. Compared with adult recipients, NODAT is less prevalent in pediatric renal transplant recipients; however, some risk factors for its development in young patients have been defined. We report four pediatric renal transplant recipients with ARPKD who developed NODAT. We review the current pediatric NODAT literature and hypothesize that ARPKD may be an additional risk factor for NODAT.

[Diabetes in liver cirrhosis]

The prevalence of overt diabetes mellitus (DM) in liver cirrhosis is about 30%. However, DM or impaired glucose tolerance can be observed in 90% after an oral glucose tolerance test in patients with normal fasting plasma glucose. Type 2 DM may produce cirrhosis, whereas DM may be a complication of cirrhosis. The latter is known as «hepatogenous diabetes». Overt and subclinical DM is associated with liver complications and death in cirrhotic patients. Treating diabetes is difficult in cirrhotic patients because of the metabolic impairments due to liver disease and because the most appropriate pharmacologic treatment has not been defined. It is also unknown if glycemic control with hypoglycemic agents has any impact on the course of the liver disease.

The nutritional management of hepatic encephalopathy in patients with cirrhosis: International Society for Hepatic Encephalopathy and Nitrogen Metabolism Consensus

Nitrogen metabolism plays a major role in the development of hepatic encephalopathy (HE) in patients with cirrhosis. Modulation of this relationship is key to the management of HE, but is not the only nutritional issue that needs to be addressed. The assessment of nutritional status in patients with cirrhosis is problematic. In addition, there are significant sex-related differences in body composition and in the characteristics of tissue loss, which limit the usefulness of techniques based on measures of muscle mass and function in women. Techniques that combine subjective and objective variables provide reasonably accurate information and are recommended. Energy and nitrogen requirements in patients with HE are unlikely to differ substantially from those recommended in patients with cirrhosis per se viz. 35-45 kcal/g and 1.2-1.5g/kg protein daily. Small meals evenly distributed throughout the day and a late-night snack of complex carbohydrates will help minimize protein utilization. Compliance is, however, likely to be a problem. Diets rich in vegetables and dairy protein may be beneficial and are therefore recommended, but tolerance varies considerably in relation to the nature of the staple diet. Branched chain amino acid supplements may be of value in the occasional patient intolerant of dietary protein. Increasing dietary fiber may be of value, but the utility of probiotics is, as yet, unclear. Short-term multivitamin supplementation should be considered in patients admitted with decompensated cirrhosis. Hyponatremia may worsen HE; it should be prevented as far as possible and should always be corrected slowly.

CONCLUSION

Effective management of these patients requires an integrated multidimensional approach. However, further research is needed to fill the gaps in the current evidence base to optimize the nutritional management of patients with cirrhosis and HE.

Clinical availability of nonalcoholic fatty liver disease as an early predictor of type 2 diabetes mellitus in Korean men: 5-year prospective cohort study

There have been several reports about the clinical association between type 2 diabetes mellitus (DM) and nonalcoholic fatty liver disease (NAFLD). However, most of the studies were about the unilateral effects of type 2 DM on NAFLD, and studies on the reverse relation are rare. Thus, this study was designed to investigate the effect of NAFLD on type 2 DM. We conducted a prospective cohort study on 25,232 Korean men without type 2 DM for 5 years. We serially checked the various metabolic factors including fasting glucose and hemoglobin A1c (HbA1c), and monitored the development of type 2 DM. The incidence rate of type 2 DM was compared according to the degree of NAFLD (normal, mild, and moderate to severe), and a Cox proportional hazards model was used to measure the hazard ratios (HRs) of NAFLD on type 2 DM. The incidence rate of type 2 DM increased according to the degree of NAFLD (normal: 7.0%, mild: 9.8%, moderate to severe: 17.8%, P < 0.001). Even after adjusting for other multiple covariates, the HRs (95% confidence interval [CI]) for type 2 DM development was higher in the mild group (1.09; 0.81-1.48) and moderate to severe group (1.73; 1.00-3.01) compared to the normal group, respectively (P for trend <0.001).

CONCLUSION

The development of type 2 DM is potentially more associated with more progressive NAFLD than a normal or milder state. In addition, NAFLD was an independent risk factor for the future development of type 2 DM. These results suggest the potential availability of NAFLD as an early predictor of type 2 DM.

Lipid serum profile in patients with viral liver cirrhosis

OBJECTIVE

Our main aim was to investigate the serum lipid levels in a series of patients with liver cirrhosis of viral origin.

SUBJECTS AND METHODS

The study comprised 90 patients, 60 with viral liver cirrhosis, equally divided between hepatitis virus C (HCV) and B (HBV) etiologies, and 30 control patients with no known liver pathology. Patients were investigated during a 5-year period in the 1st Medical Clinic of the Emergency County Hospital of Craiova, Romania. The following series of serum lipid parameters were recorded: lipemia, total cholesterol and cholesteryl ester, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, very-low-density lipoprotein (VLDL) cholesterol and triglyceride (TG) values. Statistical analysis of these parameters was performed using the ANOVA test followed by Tukey multiple comparison tests to compare replicate means; p < 0.05 was considered statistically significant.

RESULTS

We observed significantly lower values for serum lipids (543.5 and 549.37 mg/dl in the HBV and HCV cirrhosis subgroups, compared with 649.9 mg/dl in controls), total cholesterol (143.6 and 147.9 vs. 198.0 mg/dl, respectively), cholesteryl esters (83.6 and 80, compared to 147.9 mg/dl, respectively), LDL cholesterol (91.6 and 88.5 vs. 132.4 mg/dl) in both cirrhosis groups when compared with controls (p < 0.001), as well as HDL cholesterol (32.1 and 36.9 vs. 47.3 mg/dl, p < 0.05). However, TG and VLDL cholesterol values of controls and cirrhosis groups were similar (p > 0.05). We did not register any differences between the two cirrhosis groups (p > 0.05).

CONCLUSION

Our data showed that both HCV and HBV cirrhosis severely impaired liver lipid metabolism. Late stages of the disease resulted in a pseudonormalization of VLDL cholesterol and TG values.

Effects of GLUT4 expression on insulin resistance in patients with advanced liver cirrhosis

Decreased glucose tolerance and diabetes are frequently observed in advanced liver cirrhosis patients and may be related to insulin resistance. Glucose transporter-4 (GLUT4), one of the most important glucose transporters, plays a key role in the development of type 2 diabetes. In order to study the mechanism of insulin resistance in liver cirrhosis patients, we measured the insulin sensitivity index and determined the GLUT4 protein and mRNA contents of skeletal muscle by Western blotting and reverse transcription-polymerase chain reaction (RT-PCR), respectively, in normal people and liver cirrhosis patients. The results showed that the levels of glucose, insulin, and C-peptide in two liver cirrhosis groups were higher and the insulin sensitivity index lower than those of the normal control group. The sensitivity of insulin may decrease with the decline of liver function. However, the contents of GLUT4 protein and mRNA in patients with advanced liver cirrhosis were similar to those of normal controls. In conclusion, insulin resistance is observed in patients with advanced liver cirrhosis but may not be correlated with the skeletal contents of GLUT4 protein and mRNA.

Why does NAFLD predict type 2 diabetes?

Based on the "lipotoxic" hypothesis, the free fatty acid flux from the excessive amount of adipose tissue toward the peripheral tissues would induce the development of insulin resistance especially when the triglyceride storage or the concentration of intermediate fat metabolites (diacylglycerides, ceramides) within the cytoplasm of these cells become excessive. Nonalcoholic fatty liver disease (NAFLD) includes a wide spectrum of liver damage, ranging from simple steatosis to steatohepatitis and advanced fibrosis. NAFLD is associated with general and intra-abdominal obesity and with a reduced ability of insulin to stimulate metabolic pathways in the liver itself and in other tissues. There are animal models and models in human diseases sustaining the hypothesis that a primary hepatic disease may determine the development of type 2 diabetes (T2DM). Epidemiologic data generated on surrogate markers of NAFLD (transaminases and γ-glutamyltransferase), semiquantitative assessment of fatty liver (ultrasound), and surrogate algorithms of NAFLD also support a causative effect of NAFLD on the risk to develop T2DM. In spite of the presence of these indirect associations, a clear-cut link between NAFLD and abnormal β-cell function is yet to be reported. Therefore, more data are warranted to prove what is considered a likely causative relationship between NAFLD and T2DM.

High prevalence of diabetes mellitus in patients with liver cirrhosis

AIMS

The reported prevalence of Type 2 diabetes mellitus in patients with liver cirrhosis is five times higher than in the general population. However, these data were never adjusted for classical risk factors for Type 2 diabetes. We therefore investigated the association between cirrhosis and Type 2 diabetes and adjusted for known risk factors for Type 2 diabetes.

METHODS

We reviewed medical files for presence of Type 2 diabetes and potential confounders in 94 patients with cirrhosis (cases) and compared these with a control group of 107 patients with non-ulcer dyspepsia. Multiple logistic regression analysis was used to adjust for potential confounders.

RESULTS

The aetiology of our cirrhosis population was alcohol (59%), viral hepatitis (10%), biliary cirrhosis (3%) or cryptogenic (28%). Prevalence of Type 2 diabetes was significantly higher in patients with cirrhosis than in control subjects: 35/94 (37%) vs. 7/107 (7%) (OR 8.5, 95% CI 3.5–20.2, P < 0.001). After adjustment for age, sex, family history of Type 2 diabetes, alcohol use and BMI, cirrhosis remained significantly associated with Type 2 diabetes (OR 13.6, 95% CI 4.3–42.9, P < 0.001). Most cases of Type 2 diabetes were already diagnosed before diagnosis of cirrhosis (21/35, 60%) or were incidentally found together with cirrhosis (5/35, 14%).

CONCLUSIONS

Liver cirrhosis had a strong, independent association with Type 2 diabetes. Classical risk factors such as family history and BMI could not explain the high Type 2 diabetes prevalence in cirrhosis. Therefore, a liver-derived factor might aggravate glucose intolerance and cause Type 2 diabetes in cirrhosis. In addition, Type 2 diabetes might also cause cirrhosis through liver steatosis and fibrosis.

Dysregulation of plasma ghrelin in alcoholic cirrhosis

OBJECTIVE

Abnormalities in circulating ghrelin have been reported in chronic liver disease. This study assessed the response of anabolic peptides ghrelin, growth hormone (GH) and insulin-like growth factor 1 (IGF-1) in patients with alcoholic cirrhosis and healthy subjects to oral glucose. In a previous study, using oral glucose we identified loss of ghrelin regulation in nonalcoholic steato-hepatitis. PATIENTS/DESIGN/MEASUREMENTS: Fourteen patients with alcoholic cirrhosis were compared with 11 healthy subjects. Patients with cirrhosis were studied when adjudged clinically stable in hospital. After an overnight fast, they ingested 100-g glucose dissolved in 250 ml of water. Blood was sampled before and every 20 minutes after ingestion for 120 minutes. Plasma acylated and des-acyl ghrelin, GH, IGF-1 and insulin were assayed by ELISA.

RESULTS

Expressed as median (95% CI): 120-minutes integrated acylated ghrelin was 26 (19-66) in controls compared to 170 (129-252) pg/ml per hour in patients with cirrhosis; P < 0.001. Both groups exhibited a normal postglucose plasma total ghrelin profile. Among patients with cirrhosis (compared to controls), growth hormone was increased 15-fold and IGF-1 decreased 4-fold. Acylated ghrelin correlated with GH (Spearman r = 0.69, P = 0.0015) in control subjects but not in patients with cirrhosis.

CONCLUSIONS

Acylated ghrelin is markedly increased in alcoholic cirrhosis, with apparent preservation of normal postprandial mechanisms of gastric ghrelin secretion. GH is also increased; however, its correlation with acylated ghrelin (confirmed in healthy subjects) is absent in patients with cirrhosis. Despite increased ghrelin and GH, patients with alcoholic cirrhosis remain anorexic and catabolic suggesting potential tissue resistance to the actions of these anabolic peptides.

Long-term results of balloon-occluded retrograde transvenous obliteration for gastric fundal varices: hepatic deterioration links to portosystemic shunt syndrome

BACKGROUND AND AIMS

It is well known that a large portosystemic shunt develops during portal hypertension. In this study, we studied the long-term effects of a large splenorenal shunt (SRS) on liver function and survival.

METHODS

The subjects were divided into three groups: an SRS (-) group consisting of cirrhotic patients without SRS; an SRS (+) group consisting of patients with gastric fundal varices and SRS; and a balloon-occluded retrograde transvenous obliteration (B-RTO) group with a completely obliterated SRS by B-RTO. We compared the following among these groups: the total bilirubin levels, serum albumin levels, prothrombin times, changes in Child-Pugh scores, and survival rates.

RESULTS

After a 3-year follow-up period the Child-Pugh scores showed significant differences among the SRS (+), SRS (-), and B-RTO groups. The score worsened for the SRS (+) group. The cumulative survival rates were significantly different between the SRS (+) and SRS (-) groups and between the SRS (+) and B-RTO groups. The vital prognosis worsened for the SRS (+) group.

CONCLUSIONS

The presence of a large splenorenal shunt (portosystemic shunt) was indicated to lower liver function and vital prognosis. B-RTO, which completely obliterates large splenorenal shunts, inhibited the lowering of hepatic functional reserve and the worsening of vital prognosis, indicating a protective role. Liver pathology and the presence of a large portosystemic shunt each separately result in progressive liver dysfunction and worsen the survival rate. We found that such a pathological condition had occurred due to a large portosystemic shunt, and it should be called 'portosystemic shunt syndrome.'

Effect of long-term late-evening snack on health-related quality of life in cirrhotic patients

AIM

In patients with liver cirrhosis, abnormal energy metabolism induces low health-related quality of life (HRQOL) scores. However, late-evening snack (LES) prevents morning starvation in cirrhotic patients. Our aim is to assess the effect of long-term LES on HRQOL in cirrhotic patients, using the 36-item Short Form (SF-36) health survey.

METHODS

Thirty-nine cirrhotic patients classified as Child-Pugh grade A were recruited. The patients were randomly divided into two groups: 24 were assigned to the non-LES group and 15 to the LES group. SF-36 scores, anthropometric data and serum biochemical parameters were examined in the non-LES and LES groups at 0, 6 and 12 months.

RESULTS

Neither anthropometric data nor laboratory data showed significant differences between the non-LES and the LES groups at 0, 6 and 12 months. The role-emotional (RE) HRQOL scores at 6 months and mental health (MH) scores at 6 and 12 months were significantly reduced from the baseline level in the non-LES group. In contrast, these scores remained unchanged in the LES group. General health perception (GH) scores at 12 months, RE at 6 months and MH at 6 and 12 months in the LES group were significantly higher than those of the non-LES group.

CONCLUSION

Long-term LES administration may be helpful in maintaining higher HRQOL in patients with cirrhosis.

Liver cirrhosis and diabetes: Risk factors, pathophysiology, clinical implications and management

About 30% of patients with cirrhosis have diabetes mellitus (DM). Nowadays, it is a matter for debate whether type 2 DM in the absence of obesity and hypertriglyceridemia may be a risk factor for chronic liver disease. DM, which develops as a complication of cirrhosis, is known as “hepatogenous diabetes”. Insulin resistance in muscular and adipose tissues and hyperinsulinemia seem to be the pathophysiologic bases of diabetes in liver disease. An impaired response of the islet β-cells of the pancreas and hepatic insulin resistance are also contributory factors. Non-alcoholic fatty liver disease, alcoholic cirrhosis, chronic hepatitis C (CHC) and hemochromatosis are more frequently associated with DM. Insulin resistance increases the failure of the response to treatment in patients with CHC and enhances progression of fibrosis. DM in cirrhotic patients may be subclinical. Hepatogenous diabetes is clinically different from that of type 2 DM, since it is less frequently associated with microangiopathy and patients more frequently suffer complications of cirrhosis. DM increases the mortality of cirrhotic patients. Treatment of the diabetes is complex due to liver damage and hepatotoxicity of oral hypoglycemic drugs. This manuscript will review evidence that exists in relation to: type 2 DM alone or as part of the metabolic syndrome in the development of liver disease; factors involved in the genesis of hepatogenous diabetes; the impact of DM on the clinical outcome of liver disease; the management of DM in cirrhotic patients and the role of DM as a risk factor for the occurrence and exacerbation of hepatocellular carcinoma.

Insulin-like growth factor binding protein 1 as a novel specific marker of hepatic insulin sensitivity

BACKGROUND AND AIMS

The liver is the main source and insulin the main regulator of IGF binding protein 1 (IGFBP-1) in humans. Here we examined how serum IGFBP-1 concentrations are related to directly measured hepatic insulin sensitivity and liver fat content in humans.

METHODS

We measured fasting serum (fS) IGFBP-1 concentrations and liver fat content by proton magnetic resonance spectroscopy in 113 nondiabetic subjects. In addition, hepatic insulin sensitivity was measured using the euglycemic hyperinsulinemic clamp (insulin 0.3 mU/kg.min) technique in combination with the infusion of [3-(3)H]glucose in 78 subjects.

RESULTS

fS-IGFBP-1 concentrations were inversely related to liver fat content (r = -0.38, P < 0.0001). Of circulating parameters, fS-IGFBP-1 was better correlated to hepatic insulin sensitivity (r = 0.48, P < 0.0001) than fS-insulin (r = -0.42, P = 0.0001), fS-C-peptide (r = -0.41, P = 0.0002), fS-triglyceride (r = -0.33, P = 0.003), or fS-high-density lipoprotein cholesterol (r = 0.30, P = 0.007). In multiple linear regression analyses, body mass index (P < 0.0001) and fS-IGFBP-1 (P = 0.008), but neither age nor gender, were independently associated with hepatic insulin sensitivity (P < 0.0001 for ANOVA). Neither fS-insulin nor fS-C-peptide were independent determinants of hepatic insulin sensitivity after adjusting for age, gender, and body mass index.

CONCLUSIONS

fS-IGFBP-1 is inversely correlated with liver fat and is an obesity-independent and liver-specific circulating marker of hepatic insulin sensitivity.

Muscle GLUT4 in cirrhosis

BACKGROUND/AIMS

The insulin-dependent glucose transporter GLUT4 mediates 50-80% of whole body glucose uptake, but its relation to the frequent glucose intolerance in patients with liver cirrhosis is unknown.

METHODS

Thirty patients and seven healthy controls underwent a 2-h oral glucose tolerance test and later a muscle biopsy. Levels of GLUT4 total protein and mRNA content were determined in muscle biopsies by polyclonal antibody labelling and RT-PCR, respectively.

RESULTS

GLUT4 protein content in the cirrhosis group was not different from that of the controls, but at variance with the control subjects it correlated closely with measures of glucose tolerance (R(2)=0.45; p=0.003). GLUT4 mRNA of the patients with cirrhosis was reduced to 56% of control value (95% ci: 27-86%; p=0.015) and was inversely related to the level of basal hyper-insulinemia (R(2)=0.39; p=0.004).

CONCLUSIONS

In cirrhosis GLUT4 protein content was quantitatively intact, while limiting glucose tolerance. This indicates loss of redundancy of the major glucose transport system, possibly related to the markedly decreased expression of its gene. Hyper-insulinemia may be a primary event. Our findings implicate the muscular GLUT4 system in the glucose intolerance of liver cirrhosis by a mechanism different from that in diabetes.

Role of meal carbohydrate content for the imbalance of plasma amino acids in patients with liver cirrhosis

BACKGROUND AND AIM

Imbalance of circulating branched chain amino acids (BCAA) versus aromatic amino acids (AAA) and hyperinsulinemia are common metabolic alterations in patients with liver cirrhosis. The aim of this study was to characterize the effect of the carbohydrate component of a protein-rich mixed meal on postprandial plasma concentrations of 21 amino acids, insulin and C-peptide in patients with compensated liver cirrhosis. Furthermore, the effect of a dietary intervention on the metabolic alterations in cirrhotic patients was examined.

METHODS

Eighteen patients with cirrhosis and 12 healthy volunteers received a protein-rich meal (pork filet 200 g) with or without carbohydrates (bread 50 g, glucose 20 g). A subgroup of four cirrhotic patients received an isoenergetic (117 kJ/kg bw) carbohydrate-enriched (60%) and -restricted (20%) diet for 7 days each.

RESULTS

In the cirrhotic patients, basal plasma insulin and C-peptide concentrations were significantly elevated. The ingestion of a protein-rich meal without additional carbohydrates led to a significantly greater increase of insulin and C-peptide in the cirrhotic patients compared to controls. Postprandial increases of leucine and isoleucine were reduced, whereas those of phenylalanine were higher in cirrhotic patients. The addition of carbohydrates led to higher insulin and C-peptide plasma concentrations in cirrhotic patients. Postprandial BCAA increases were more impaired in the cirrhotic group after additional carbohydrate ingestion (46%vs 82%). After the carbohydrate-restricted diet for 7 days BCAA plasma levels increased but the BCAA/AAA ratio remained unaltered.

CONCLUSIONS

The carbohydrate content of a meal enhances reduction of BCAA plasma concentrations in clinically stable cirrhotic patients. An imbalanced BCAA/AAA ratio cannot be avoided by a carbohydrate-reduced diet alone, supporting mandatory BCAA supplementation.

Nutritional treatment of a patient with hepatic cirrhosis with the novel low glycemic index liquid food (Inslow)

A sixty-six year-old patient with liver cirrhosis and diabetes was nutritionally treated by administration of the low glycemic index liquid food (Inslow) as a late evening sack (LES) for 6 weeks. The mean energy intake increased from 825+/-48 kcal/d to 1567+/-66 kcal/d after the 6-week treatment period. The fasting glucose level did not change, remaining at about 100 mg/dl throughout this period. Interestingly, the amount of insulin administered was reduced from 38 units before treatment to 28 units in the fifth week of treatment without a change in the fasting glucose level. This indicates a marked improvement in insulin sensitivity due to Inslow administration in this patient. In conclusion, the long-term administration of Inslow as an LES may be an effective treatment for cirrhotic patients.

Impaired insulin action despite upregulation of proximal insulin signaling: novel insights into skeletal muscle insulin resistance in liver cirrhosis

BACKGROUND/AIMS

Disturbance in glucose metabolism is a common feature in liver diseases and this is associated with skeletal muscle insulin resistance. However, the underlying molecular mechanisms are unclear. To characterize skeletal muscle insulin resistance associated with liver disease, we examined muscles from animals after an acute, 5 weeks perturbation of the common bile duct. Clinical findings, elevated plasma levels of liver enzymes and histological examinations confirmed cirrhosis.

METHODS/RESULTS

: Cirrhotic animals were insulin resistant and this was associated with reduced glucose transport into muscles. Interestingly, activity in the proximal part of the insulin signaling cascade was not decreased, as evinced by increased activity of key enzymes in the signal to glucose transport. Expression of the glucose transporter, GLUT4, was normal. So together these results indicate that signaling downstream of PKB/Akt and/or the translocation of GLUT4 is impaired in skeletal muscle from cirrhotic animals.

CONCLUSIONS

In conclusion, in an animal model of liver cirrhosis whole body insulin resistance is associated with insulin resistance in skeletal muscles. Unlike other common forms of insulin resistance, muscles from cirrhotic animals have increased activity in the proximal insulin signaling cascade. This emphasizes the fact that skeletal muscle insulin resistance associated with liver cirrhosis is a unique entity.

Diabetes in chronic liver disease: from old concepts to new evidence

The liver is one of the principal organs involved in glucose metabolism together with skeletal muscle and adipose tissue. A link between diabetes and chronic liver disease (CLD) was first observed in the early half of the last century, but to date several questions remain unsolved. Altered glucose tolerance has been well described in alcoholic CLD, non-alcoholic fatty liver disease, chronic hepatitis C and portal hypertension. Moreover, insulin resistance is assuming an ever-growing importance in CLD; chronic hepatitis C has recently been proposed as a metabolic disease and insulin sensitivity as a predictive factor for liver fibrosis.CLD is also complicated by acquired growth hormone (GH) resistance, characterized by low concentrations of insulin-like growth factor-1 (IGF-1) with respect to normal or elevated GH levels. GH resistance in CLD is determined by several factors, including malnutrition, impaired liver function and reduced expression of hepatic GH receptors. We recently described the possible role of tumour necrosis factor-alpha (TNF-alpha) in blunting the hepatic response to GH in patients with chronic hepatitis C. The role of GH in impaired glucose metabolism is well known, and recent evidence suggests a receptor and/or post-receptor modulation of insulin signalling. Moreover, as in other chronic inflammatory conditions, pro-inflammatory cytokines may directly modulate the signal cascade that follows insulin binding to its receptor in the course of CLD. In this review, the proposed links between impaired glucose tolerance and CLD are analysed, special emphasis being focussed on the most recent findings concerning the interplay of chronic inflammation, GH resistance and insulin resistance.

Effect of late evening snack with rice ball on energy metabolism in liver cirrhosis

OBJECTIVE

This study investigates the effects of a late evening snack (LES), of 200 kcal of rice ball, on energy metabolism in cirrhotic patients. Impaired nutritional metabolism has been associated with cirrhosis, and frequent intake of small meals may prevent early-onset starvation, and maintain nourishment in these patients.

SUBJECTS

Twenty-one cirrhotic patients and 26 control subjects (Control) were recruited for this study. Patients were subsequently treated by LES (LC-LES) and by a non-LES regimen (LC-NLES).

METHOD

Resting energy expenditure and respiratory quotient (RQ) were assessed by indirect calorimetry at 0830, 1130 and 1430. Blood glucose and non-esterified fatty acids (NEFA) were measured just before the energy metabolism measurements. The regular diet included three major meals and LES, at 0900, 1200, 1800 and 2100, respectively. The Control and LC-NLES groups received only the major meals, whereas the LC-LES group received three meals plus 200 kcal LES for 7 days. There was no difference in the total energy intake among Control, LC-NLES and LC-LES groups.

RESULTS

Respiratory quotient in LC-NLES was significantly lower than that of Control at 0830. Respiratory quotient value in LC-LES significantly elevated from that in LC-NLES. The RQ values did not differ among Control, LC-NLES and LC-LES at 2 h after the meal (1130 and 1430). Non-esterified fatty acids in LC-LES were lower than that in LC-NLES after overnight fasting.

CONCLUSIONS

The ingestion of a 200 kcal rice ball LES can improve the nutritional metabolism in cirrhotic patients.

Contribution of defects in glucose uptake to carbohydrate intolerance in liver cirrhosis: assessment during physiological glucose and insulin concentrations

It is well established that subjects with liver cirrhosis are insulin resistant, but the contribution of defects in insulin secretion and/or action to glucose intolerance remains unresolved. Healthy individuals and subjects with liver cirrhosis were studied on two occasions: 1) an oral glucose tolerance test was performed, and 2) insulin secretion was inhibited and glucose was infused in a pattern and amount mimicking the systemic delivery rate of glucose after a carbohydrate meal. Insulin was concurrently infused to mimic a healthy postprandial insulin profile. Postabsorptive glucose concentrations were equal (5.36 +/- 0.12 vs. 5.40 +/- 0.25 mmol/l, P = 0.89), despite higher insulin (P < 0.01), C-peptide (P < 0.01), and free fatty acid (P = 0.05) concentrations in cirrhotic than in control subjects. Endogenous glucose release (EGR; 11.50 +/- 0.50 vs. 11.73 +/- 1.00 mumol.kg(-1).min(-1), P = 0.84) and the contribution of gluconeogenesis to EGR (6.60 +/- 0.47 vs. 6.28 +/- 0.64 mumol.kg(-1).min(-1), P = 0.70) were unaltered by cirrhosis. A minimal model recently developed for the oral glucose tolerance test demonstrated an impaired insulin sensitivity index (P < 0.05), whereas the beta-cell response to glucose was unaltered (P = 0.72). During prandial glucose and insulin infusions, the integrated glycemic response was greater in cirrhotic than in control subjects (P < 0.05). EGR decreased promptly and comparably in both groups, but glucose disappearance was insufficient at the prevailing glucose concentration (P < 0.05). Moreover, identical rates of [3-(3)H]glucose infusion produced higher tracer concentrations in cirrhotic than in control subjects (P < 0.05), implying a defect in glucose uptake. In conclusion, carbohydrate intolerance in liver cirrhosis is determined by insulin resistance and the ability of glucose to stimulate insulin secretion. During prandial glucose and insulin concentrations, EGR suppression was unaltered, but glucose uptake was impaired, which demonstrates that intolerance can be ascribed to a defect in glucose uptake, rather than abnormalities in glucose production or beta-cell function. Although insulin secretion ameliorates glucose intolerance, impaired glucose uptake during physiological glucose and insulin concentrations produces marked and sustained hyperglycemia, despite concurrent abnormalities in glucose production or insulin secretion.