Elevated bound leptin correlates with energy expenditure in cirrhotics

Protein Catabolism and the Dysregulation of Energy Intake-Related Hormones May Play a Major Role in the Worsening of Malnutrition in Hospitalized Cirrhotic Patients

Malnutrition in cirrhotic patients is extremely common and has a multifactorial aetiology, whose constitutive elements have not been completely elucidated yet. Protein depletion is particularly important and an imbalance of hormones regulating hunger and satiety may be an important additive factor. The diagnosis and treatment of malnutrition are extremely important since malnutrition is associated with higher complication rates and mortality. Our observational study aimed to study protein status and energy intake-related hormone levels in a cohort of hospitalized cirrhotic patients. We enrolled 50 hospitalized and clinically stable cirrhotic patients and assessed their nutritional status with anthropometric measurements and nitrogen balance. In a subgroup of 16 patients and 10 healthy controls, circulating ghrelin and leptin levels were studied. We observed that 60% of our patients were malnourished on the basis of the mid-arm muscle circumference values; the recorded daily protein intake was tendentially insufficient (mean protein intake of 0.7 ± 0.5 g protein/kg vs. recommended intake of 1.2–1.5 g of protein/kg/die). Cirrhotic patients had lower circulating levels of both ghrelin and leptin compared to healthy controls. In conclusion, hospitalized cirrhotic patients face a catabolic state and an imbalance in hormones regulating food intake and satiety, and these elements may play a major role in the genesis and/or the worsening of malnutrition.

Influencing Factors and Molecular Pathogenesis of Sarcopenia and Osteosarcopenia in Chronic Liver Disease

The liver plays a pivotal role in nutrient/energy metabolism and storage, anabolic hormone regulation, ammonia detoxification, and cytokine production. Impaired liver function can cause malnutrition, hyperammonemia, and chronic inflammation, leading to an imbalance between muscle protein synthesis and proteolysis. Patients with chronic liver disease (CLD) have a high prevalence of sarcopenia, characterized by progressive loss of muscle mass and function, affecting health-related quality of life and prognosis. Recent reports have revealed that osteosarcopenia, defined as the concomitant occurrence of sarcopenia and osteoporosis, is also highly prevalent in patients with CLD. Since the differentiation and growth of muscles and bones are closely interrelated through mechanical and biochemical communication, sarcopenia and osteoporosis often progress concurrently and affect each other. Osteosarcopenia further exacerbates unfavorable health outcomes, such as vertebral fracture and frailty. Therefore, a comprehensive assessment of sarcopenia, osteoporosis, and osteosarcopenia, and an understanding of the pathogenic mechanisms involving the liver, bones, and muscles, are important for prevention and treatment. This review summarizes the molecular mechanisms of sarcopenia and osteosarcopenia elucidated to data in hopes of promoting advances in treating these musculoskeletal disorders in patients with CLD.

Malnutrition in Patients with Liver Cirrhosis

Liver cirrhosis is an increasing public health threat worldwide. Malnutrition is a serious complication of cirrhosis and is associated with worse outcomes. With this review, we aim to describe the prevalence of malnutrition, pathophysiological mechanisms, diagnostic tools and therapeutic targets to treat malnutrition. Malnutrition is frequently underdiagnosed and occurs-depending on the screening methods used and patient populations studied-in 5-92% of patients. Decreased energy and protein intake, inflammation, malabsorption, altered nutrient metabolism, hypermetabolism, hormonal disturbances and gut microbiome dysbiosis can contribute to malnutrition. The stepwise diagnostic approach includes a rapid prescreen, the use of a specific screening tool, such as the Royal Free Hospital Nutritional Prioritizing Tool and a nutritional assessment by dieticians. General dietary measures-especially the timing of meals-oral nutritional supplements, micronutrient supplementation and the role of amino acids are discussed. In summary malnutrition in cirrhosis is common and needs more attention by health care professionals involved in the care of patients with cirrhosis. Screening and assessment for malnutrition should be carried out regularly in cirrhotic patients, ideally by a multidisciplinary team. Further research is needed to better clarify pathogenic mechanisms such as the role of the gut-liver-axis and to develop targeted therapeutic strategies.

The Inter-Relation between Leptin Receptor (Q223R) Gene Polymorphism and the Risk of Egyptian Patients with HCC

Background:

The relationship of leptin (LEP) and polymorphism of leptin receptor (LEPR) were studied in patients with hepatocellular carcinoma (HCC) and compared with those with liver cirrhosis to find out the extent of the risk of LEPR on patients with HCC.

Methods:

Serum LEP level and LEPR Q223R gene polymorphism were determined in 300 patients with liver disease categorized equally into five groups’ healthy volunteers, patients with hepatitis C (HCV), patients with non-alcoholic steatohepatitis (NASH), liver cirrhosis and HCC. LEPR gene was amplified by polymerase chain reaction (PCR) then digested by the MSP1 restriction enzyme.

Results:

The isolated 212 bp of LEPR was sequenced. The serum LEP level was reduced in patients with cirrhotic and HCC. Serum LEP level had negatively correlated with both tumor grade and size in HCC patients. The data obtained from restriction fragment length polymorphismPCR and sequencing revealed the existence of a novel synonymous Q223R single nucleotide polymorphism (SNP) in exon 223 of LEPR gene (1137101). LEPR Gln223Arg, GG and GA genotypes were found in all studied groups. LEPR Gln223Arg, AA genotype was found in NASH, HCC, and control. LEPR Gln223Arg GA genotype is associated with some patients with HCC.

Conclusion:

GA genotype of LEPR Gln223Arg may be regarded as a probable genetic risk factor for Egyptian patients with HCC.

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.

Molecular Mechanism Contributing to Malnutrition and Sarcopenia in Patients with Liver Cirrhosis

Liver cirrhosis is frequently accompanied by disease-related malnutrition (DRM) and sarcopenia, defined as loss of skeletal muscle mass and function. DRM and sarcopenia often coexist in cirrhotic patients and are associated with increased morbidity and mortality. The clinical manifestation of both comorbidities are triggered by multifactorial mechanisms including reduced nutrient and energy intake caused by dietary restrictions, anorexia, neuroendocrine deregulation, olfactory and gustatory deficits. Maldigestion and malabsorption due to small intestinal bacterial overgrowth, pancreatic insufficiency or cholestasis may also contribute to DRM and sarcopenia. Decreased protein synthesis and increased protein degradation is the cornerstone mechanism to muscle loss, among others mediated by disease- and inflammation-mediated metabolic changes, hyperammonemia, increased myostatin and reduced human growth hormone. The concise pathophysiological mechanisms and interactions of DRM and sarcopenia in liver cirrhosis are not completely understood. Furthermore, most knowledge in this field are based on experimental models, but only few data in humans exist. This review summarizes known and proposed molecular mechanisms contributing to malnutrition and sarcopenia in liver cirrhosis and highlights remaining knowledge gaps. Since, in the prevention and treatment of DRM and sarcopenia in cirrhotic patients, more research is needed to identify potential biomarkers for diagnosis and development of targeted therapeutic strategies.

Nutritional Challenges in Patients with Advanced Liver Cirrhosis

Patients with advanced liver cirrhosis are at risk of malnutrition and nutrition-associated complications. Significant ascites, a frequent finding in these patients, has an especially negative impact on oral nutrition. A negative caloric and protein balance can further deteriorate the already impaired synthetic function of the cirrhotic liver. An important factor in this situation is the diminished capacity of glycogen production and storage in the cirrhotic liver and, consequently, a reduced tolerability for fasting episodes. These episodes are frequently observed in hospitalized patients, e.g., while waiting for investigations, interventions or surgery. A comprehensive work-up of patients with advanced liver cirrhosis should include not only a thorough assessment regarding nutritional deficits, but also a muscularity analysis to identify patients with sarcopenia. The overall nutritional treatment goal is to cover caloric deficits and assure a sufficiently high protein intake. Furthermore, vitamin and micronutrient deficiencies should be identified and corrective measures implemented where required. Ideally, optimal nutrition management can not only prevent the progression of malnutrition and sarcopenia in patients with advanced liver cirrhosis, but positively influence the evolution of the liver disease.

Obesity paradox in advanced liver disease: obesity is associated with lower mortality in hospitalized patients with cirrhosis

BACKGROUND & AIMS

To investigate how obesity impacts inpatient mortality, length of stay (LOS) and costs in patients with cirrhosis. Obesity is a growing epidemic associated with multiple co-morbidities, increased morbidity, and a significant economic burden on healthcare. Despite the overall harmful impact of obesity, the 'obesity paradox' has been described as decreased mortality among obese vs non-obese patients in various chronic medical conditions.

METHODS

Analysis of the Nationwide Inpatient Sample (NIS) for 2012, which contains data from 44 states and 4378 hospitals. Data from all cases with primary, secondary or tertiary discharge diagnosis of cirrhosis identified by International Classification of Diseases-9 code 571.2, 571.5 571.6 were included. Primary outcomes included inpatient mortality, LOS, and hospital charges. Obesity as a predictor of mortality was defined by a predetermined obesity co-morbidity variable.

RESULTS

A total of 32,605 patients were included. Crude mortality was lower for obese cirrhotic patients (2.7% vs 3.5%, P = 0.02) than for non-obese cirrhotic patients. In contrast, median LOS was longer (4 vs 3 days, P < 0.001) and median hospital charges were higher for obese cirrhotic patients ($26 803 vs $23 447, P < 0.001) In multivariate logistic regression, obesity was associated with a lower risk of inpatient mortality (OR=0.73, 95%CI: 0.55-0.95, P = 0.02).

CONCLUSIONS

In the acute care setting, obese patients with cirrhosis have lower mortality than non-obese patients with cirrhosis, longer hospitalizations and higher healthcare cost, providing new evidence for the obesity paradox in cirrhosis. Obese cirrhotic patients are more likely to have enhanced nutritional reserve which may play a role in survival during acute illness.

Factors related to increased resting energy expenditure in men with liver cirrhosis

OBJECTIVE

Hypermetabolism in cirrhosis is associated with a high risk of complications and mortality. However, studies about underlying mechanisms are usually focussed on isolated potential determinants and specific etiologies, with contradictory results. We aimed at investigating differences in nutrition, metabolic hormones, and hepatic function between hypermetabolic and nonhypermetabolic men with cirrhosis of the liver.

PATIENTS AND METHODS

We prospectively enrolled 48 male cirrhotic inpatients. We evaluated their resting energy expenditure (REE) and substrate utilization by indirect calorimetry, body composition by dual-energy X-ray absorptiometry, liver function, and levels of major hormones involved in energy metabolism by serum sample tests. Patients with ascites, specific metabolic disturbances, and hepatocellular carcinoma were excluded.

RESULTS

REE and REE adjusted per fat-free mass (FFM) were significantly increased in cirrhotic patients. Overall, 58.3% of cirrhotic patients were classified as hypermetabolic. Groups did not differ significantly in age, etiology of cirrhosis, liver function, presence of ascites, use of diuretics, β-blockers, or presence of transjugular intrahepatic portosystemic shunts. Hypermetabolic cirrhotic patients had lower weight, BMI (P<0.05), nonprotein respiratory quotient (P<0.01), leptin (P<0.05), and leptin adjusted per fat mass (FM) (P<0.05), but higher FFM% (P<0.05) and insulin resistance [homeostatic model assessment-insulin resistance (HOMA-IR)] (P<0.05). Only HOMA-IR, leptin/FM, and FFM% were independently related to the presence of hypermetabolism.

CONCLUSION

Hypermetabolic cirrhotic men are characterized by lower weight, higher FFM%, insulin resistance, and lower leptin/FM when compared with nonhypermetabolic men. HOMA-IR, FFM%, and leptin/FM were independently associated with hypermetabolism, and may serve as easily detectable markers of this condition in daily clinical practice.

Gastrointestinal dysfunction in liver cirrhosis

Patients with liver cirrhosis exhibit several features of gut dysfunction which may contribute to the development of cirrhosis complications as well as have an impact on nutritional status and health-related quality of life. Gastrointestinal symptoms are common in cirrhosis and their pathophysiology probably involves factors related to liver disease severity, psychological distress, and gut dysfunction (e.g., increased gastric sensitivity to distension and delayed gut transit). They may lead to reduced food intake and, thus, may contribute to the nutritional status deterioration in cirrhotic patients. Although tense ascites appears to have a negative impact on meal-induced accommodation of the stomach, published data on gastric accommodation in cirrhotics without significant ascites are not unanimous. Gastric emptying and small bowel transit have generally been shown to be prolonged. This may be related to disturbances in postprandial glucose, insulin, and ghrelin levels, which, in turn, appear to be associated to insulin resistance, a common finding in cirrhosis. Furthermore, small bowel manometry disturbances and delayed gut transit may be associated with the development of small bowel bacterial overgrowth. Finally, several studies have reported intestinal barrier dysfunction in patients with cirrhosis (especially those with portal hypertension), which is related to bacterial translocation and permeation of intestinal bacterial products, e.g., endotoxin and bacterial DNA, thus potentially being involved in the pathogenesis of complications of liver cirrhosis.

Nutrition in alcoholic liver disease

The liver plays an important role in the metabolism, synthesis, storage, and absorption of nutrients. Patients with cirrhosis are prone to nutritional deficiencies and malnutrition, with a higher prevalence among patients with decompensated disease. Mechanisms of nutritional deficiencies in patients with liver disease are not completely understood and probably multifactorial. Malnutrition among patients with cirrhosis or alcoholic liver disease correlates with poor quality of life, increased risk of infections, frequent hospitalizations, complications, mortality, poor graft and patient survival after liver transplantation, and economic burden. Physicians, including gastroenterologists and hepatologists, should be conversant with assessment and management of malnutrition and nutritional supplementation.

Abnormal plasma peptide YY(3-36) levels in patients with liver cirrhosis

OBJECTIVE

Peptide YY(3-36) (PYY(3-36)) is a gut hormone with anorectic action that also affects energy expenditure. Anorexia and malnutrition are often observed in patients with decompensated liver cirrhosis (LC), whereas patients with LC after insertion of transjugular portosystemic stent shunts (TIPS) show normal eating behavior. The underlying mechanism of anorexia in decompensated LC and its resolution in patients with TIPS is still unclear. We thus investigated fasting and postprandial PYY(3-36) serum levels in patients with decompensated LC, patients with compensated LC with in situ TIPS, and healthy controls.

METHODS

We analyzed fasting PYY(3-36) levels in six patients with decompensated LC (four men and two women, 55 ± 11 y of age), nine patients with TIPS (seven men and two women, 48 ± 11 y of age), and 10 controls (eight men and two women, 43 ± 9 y of age) postprandially after a standardized meal of 300 kcal and during 1-h continuous parenteral nutrition. Energy expenditure was determined by indirect calorimetry.

RESULTS

At baseline PYY(3-36) was comparable in controls and patients with TIPS (91 ± 10 and 89 ± 25 ng/L) but was increased in patients with decompensated LC (165 ± 44 ng/L, P < 0.01). Although the cumulative postprandial PYY(3-36) increase was similar in controls (mean 2089 ng/240 min per liter) and patients with decompensated LC (mean 1735 ng/240 min per liter), no postprandial PYY(3-36) increase was observed in patients with TIPS (mean -579 ng/240 min per liter). Parenteral nutrition did not significantly affect PYY(3-36) levels in any group. Fasting PYY(3-36) values were negatively related to resting energy expenditure (r = -0.443, P = 0.030). PYY(3-36) was not associated to liver parameters (e.g., bilirubin, alanine aminotransferase).

CONCLUSION

Our results demonstrate an abnormal neuroendocrine regulation of PYY(3-36) in patients with decompensated LC and those with TIPS.

Prevalence and mechanisms of malnutrition in patients with advanced liver disease, and nutrition management strategies

Malnutrition is prevalent among cirrhotic patients and is an important prognostic factor. Etiologic factors include hypermetabolism, malabsorption, altered nutrient metabolism, and anorexia. It is a challenge to manage nutrition in cirrhotic patients because of alterations to metabolic and storage functions of the liver; use of traditional assessment tools, such as anthropometric and biometric measures, is difficult because of complications such as ascites and inflammation. In addition to meeting macro- and micronutrient requirements, the composition and timing of supplements have been proposed to affect efficacy of nutrition support. Studies have indicated that branched chain aromatic acid can be given as therapeutic nutrients, and that probiotics and nocturnal feeding improve patient outcomes.

Increased levels of serum leptin are a risk factor for the recurrence of stage I/II hepatocellular carcinoma after curative treatment

Obesity and related adipocytokine disbalance increase the risk of hepatocellular carcinoma. To determine the impact of increased levels of leptin, an obesity-related adipocytokine, on the recurrence of hepatocellular carcinoma, we conducted a prospective case-series analysis. Eighty-five consecutive primary hepatocellular carcinoma patients at our hospital from January 2006 to December 2008 were analyzed. Serum leptin level significantly correlated with Body Mass Index, total body fat, and the amount of subcutaneous fat. They included 33 with stage I/II, who underwent curative treatment. The factors contributing to recurrence of hepatocellular carcinoma, including leptin, were subjected to univariate and multivariate analyses using the Cox proportional hazards model. Body Mass Index (p = 0.0062), total body fat (p = 0.0404), albumin (p = 0.0210), α-fetoprotein (p = 0.0365), and leptin (p = 0.0003) were significantly associated with the recurrence of hepatocellular carcinoma in univariate analysis. Multivariate analysis suggested that leptin (hazard ratio 1.25, 95% CI 1.07–1.49, p = 0.0035) was a sole independent predictor. Kaplan-Meier analysis showed that recurrence-free survival was lower in patients with greater serum leptin concentrations (>5 ng/mL, p = 0.0221). These results suggest that the serum leptin level is a useful biomarker for predicting the early recurrence of hepatocellular carcinoma.

Cytokines, liver fibrosis, and principles of nutritional support in patients with liver fibrosis

The rapid development of molecular biology has provided new paths for and led to great breakthroughs in the treatment of liver fibrosis. Now the research of targets for anti-fibrosis therapy mainly focuses on hepatic stellate cells (HSC) and cytokines related to HSC activation. Researchers are getting more concerned about the features of nutritional metabolism in patients with liver fibrosis and their relationship with prognosis because of special roles the liver plays in nutritional metabolism. Reasonable principles of nutritional support can help ameliorate symptoms, reduce complications and facilitate recovery in patients with liver fibrosis.

Total and acylated ghrelin in liver cirrhosis: correlation with clinical and nutritional status

OBJECTIVES

The pathogenesis of anorexia in cirrhotic patients is complex and the appetite-modulating hormone ghrelin could be involved. Acylated ghrelin is the biologically active form that modifies insulin sensitivity and body composition. The aim of the present study was to compare acylated and total ghrelin concentration in patients with liver cirrhosis and to investigate the possible relationship between ghrelin and clinical and nutritional parameters.

DESIGN AND METHODS

Sixty patients with viral liver cirrhosis who did not have hepatocellular carcinoma or acute infections were studied. Twenty healthy volunteers were recruited after matching for age, gender, and body mass index with the patients and served as controls. Fasting levels of total, acylated ghrelin, leptin, TNF-alpha and insulin were measured in all subjects, in addition, clinical and nutrition parameters were assessed.

RESULTS

In cirrhotic patients, plasma levels of both acylated and total ghrelin were significantly higher than those in the controls. The mean plasma acylated ghrelin levels were significantly higher in Child C cirrhosis compared to Child A and B. Ghrelin (total and acylated) were negatively correlated with leptin in cirrhotic patients confirming the fact that leptin acts as a physiological counterpart of ghrelin.

CONCLUSIONS

Nutritional and metabolic abnormalities in cirrhotic patients may be dependent on the changes in the ghrelin/leptin systems, mainly the acylated form of ghrelin.

Advances in understanding the roles of leptin and adiponectin in the pathogenesis of chronic liver diseases

Leptin and adiponectin are adipokines that are abundantly expressed in adipose tissue and have multiple biological effects related to the development of human diseases. More and more studies have demonstrated that adipokines play important roles in the pathogenesis of steatosis, steatohepatitis and liver fibrosis, especially nonalcoholic fatty liver disease (NAFLD) and chronic hepatitis C (CHC). This paper reviews the recent advances in understanding the roles of leptin and adiponectin in the pathogenesis of liver diseases.

Adipokines in liver diseases

Adipokines are polypeptides secreted in the adipose tissue in a regulated manner. While some of these molecules are expressed only by adipocytes, resident and infiltrating macrophages and components of the vascular stroma markedly contribute to expression of other adipokines. As a result, adipose tissue inflammation is associated with a modification in the pattern of adipokine secretion. Leptin, adiponectin, and resistin are the best-studied molecules in this class, but cytokines such as tumor necrosis factor or interleukin-6 are also secreted at high levels by the adipose tissue. Several other molecules have been recently identified and are actively investigated. Adipokines interfere with hepatic injury associated with fatty infiltration, differentially modulating steatosis, inflammation, and fibrosis. Several studies have investigated plasma levels of adiponectin in patients with nonalcoholic fatty liver disease, to establish correlations with the underlying state of insulin resistance and with the type and severity of hepatic damage. Hepatitis C is another disease where adipokines may represent a link between viral infection, steatosis, and metabolic disturbances. Identification of the mediators secreted by expanded adipose tissue and their pathogenic role is pivotal in consideration of the alarming increase in the prevalence of obesity and of the detrimental role that this condition exerts on the course of liver diseases.

Fasting and postprandial plasma ghrelin levels are decreased in patients with liver failure previous to liver transplantation

Anorexia is a problem of paramount importance in patients with advanced liver failure. Ghrelin has important actions on feeding and weight homeostasis. Concentrations of ghrelin are controversial in liver cirrhosis. Our aim was to study fasting ghrelin and their response to an oral glucose tolerance test (OGTT) in liver failure patients and normal subjects.

METHODS

We included 16 patients with severe liver failure prior to liver transplantation. As a control group we included 10 age- and BMI-matched healthy subjects. After an overnight fast, 75 g of oral glucose were administered; glucose, insulin, and ghrelin were obtained at baseline and at times 30, 60, 90, and 120 min, respectively.

RESULTS

Fasting ghrelin (median and range) were statistically significantly lower for patients compared to the controls, 527 (377-971) pg/ml vs. 643 (523-2163) pg/ml, P = 0.045, for patients and controls, respectively. The area under the curve for total ghrelin post-OGTT were lower in end-stage liver failure patients than in the control group, 58815 (44730-87420) pg/ml min vs. 76560 (56160-206385) pg/ml min, for patients and controls, respectively, P = 0.027.

CONCLUSIONS

Ghrelin levels are significantly decreased both fasting and post-OGTT in patients with liver failure candidates for transplantation. Decreased ghrelin levels could contribute to anorexia in patients with cirrhosis.

Altered basal and postprandial plasma melatonin, gastrin, ghrelin, leptin and insulin in patients with liver cirrhosis and portal hypertension without and with oral administration of melatonin or tryptophan

This investigation was designed to assess the effects of oral administration of melatonin (10 mg) and tryptophan (Trp) (500 mg) on fasting and postprandial plasma levels of melatonin, gastrin, ghrelin, leptin and insulin in 10 healthy controls and in age-matched patients with liver cirrhosis (LC) and portal hypertension. Fasting plasma melatonin levels in LC patients were about five times higher (102 +/- 15 pg/mL) than in healthy controls (22 +/- 3 pg/mL). These levels significantly increased postprandially in LC patients, but significantly less so in controls. Treatment with melatonin or L-Trp resulted in a further significant rise in plasma melatonin, both under fasting and postprandial conditions, particularly in LC patients. Moreover, plasma gastrin, ghrelin, leptin and insulin levels under fasting and postprandial conditions were significantly higher in LC subjects than in healthy controls and they further rose significantly after oral application of melatonin or Trp. This study shows that: (a) patients with LC and portal hypertension exhibit significantly higher fasting and postprandial plasma melatonin levels than healthy subjects; (b) plasma ghrelin, both in LC and healthy controls reach the highest values under fasting conditions, but decline postprandially, especially after oral application of melatonin or Trp; and (c) plasma melatonin, gastrin, ghrelin and insulin levels are altered significantly in LC patients with portal hypertension compared with that in healthy controls possibly due to their portal systemic shunting and decreased liver degradation.

Circulating adipokines and the protective effects of hyperinsulinemia in inflammatory bowel disease

OBJECTIVE

Adipokines are fat-derived hormones and cytokines with immune-modulating and metabolic properties. Most of them are associated with insulin resistance. The aim of the present investigation was to evaluate circulating levels of adipokines and glucose homeostasis in patients with inflammatory bowel disease (IBD) and to evaluate possible associations with the course and characteristics of the disease.

METHODS

Serum leptin, resistin, visfatin, retinol-binding protein-4, adiponectin, glucose, insulin, and inflammatory parameters were analyzed in 93 patients with inactive IBD (49 with Crohn's disease [CD], 44 with ulcerative colitis [UC]), 35 patients with active IBD (18 with CD, 17 with UC), and 37 age- and body mass index-matched healthy controls. Ninety-two patients were followed for 6 mo.

RESULTS

Leptin was similar in patients with IBD and controls, whereas resistin and visfatin were increased in patients with active disease but not in those in remission. In active and inactive disease, adiponectin was decreased (P < 0.001) and retinol-binding protein-4 was increased (P < 0.001) compared with controls. About 60% of patients with IBD showed increased levels of insulin, whereas serum glucose remained normal, resulting in increased homeostasis model assessment values in most patients. Hyperinsulinemia was associated with the decrease in adiponectin (r = -0.572, P < 0.001) and proved to be an independent protective factor for 6-mo maintenance of remission (P = 0.016).

CONCLUSION

IBD led to largely similar alterations in circulating adipokines and hyperinsulinemia in patients with CD and those with UC. The unexpected protective effect of hyperinsulinemia on relapse rate denotes the role of the metabolic-inflammatory response as a modulator in IBD.

Roles of adipokines in liver injury and fibrosis

Adipose tissue is now recognized as the largest endocrine organ in the body, secreting over 100 proteins termed adipokines that influence energy homeostasis, lipid physiology, inflammation, immune function and wound healing. Some of these proteins, such as TNFalpha, have important proinflammatory effects, but during hepatic injury are principally secreted at a local level within the liver. Their role in liver injury and fibrosis is beyond the scope of this review. However, circulating adipose-derived proteins such as leptin, adiponectin and resistin have important systemic effects, including the modulation of injury and fibrosis. The activities of these adipokines in the pathogenesis of liver injury and fibrosis will be the topic of this review.

Distinct roles of free leptin, bound leptin and soluble leptin receptor during the metabolic-inflammatory response in patients with liver cirrhosis

BACKGROUND

Alteration of the leptin system appears to play a role in the inflammatory-metabolic response in catabolic diseases such as chronic liver diseases.

AIM

To investigate the association between leptin components, inflammatory markers and hepatic energy and substrate metabolism.

METHODS

We investigated in vivo hepatic substrate and leptin metabolism in 40 patients employing a combination of arterial and hepatic vein catheterization techniques and hepatic blood flow measurements. In addition to metabolic, inflammatory and neuroendocrine parameters, circulating levels of free leptin, bound leptin and soluble leptin receptor were determined.

RESULTS

Compared with controls, bound leptin and soluble leptin receptor levels were significantly elevated in cirrhosis, while free leptin did not increase. In cirrhosis bound leptin was correlated with soluble leptin receptor (r = 0.70, P < 0.001). Free leptin was positively correlated with metabolic parameters such as energy storage (body fat mass; r = 0.36, P < 0.05), insulin and insulin resistance (r = 0.48; r = 0.46, P < 0.01) as well as with hepatic glucose and energy release (r = 0.35 and r = 0.40, P < 0.05). In contrast, bound leptin and soluble leptin receptor were linked to proinflammatory cytokines and sympathetic activity (r = 0.61 and r = 0.56, P < 0.01).

CONCLUSION

The components of the leptin system (free leptin, bound leptin and soluble leptin receptor) have distinct roles in metabolic and inflammatory processes in patients with liver cirrhosis. The better understanding of this metabolic and inflammatory tissue-repair response may lead to innovative new therapeutic strategies in liver disease as well as in various other catabolic diseases.

An assessment of serum leptin levels in patients with chronic viral hepatitis: a prospective study

BACKGROUND

The role of leptin in the course of liver disease due to chronic viral hepatitis (CVH) remains controversial. Our aims were to investigate the relationship between serum leptin concentrations and the severity of liver disease in a cohort of subjects with HBeAg negative chronic hepatitis B (CHB) and C (CHC) and to analyze the effect of body composition, the leptin system and insulin resistance together with viral factors on virologic response to antiviral treatment.

METHODS

We studied 50 (36 men) consecutive patients suffering from biopsy-proven CVH due to HBV (n = 25) or HCV (n = 25) infection. Thirty-two (17 men) healthy volunteers served as controls. Levels of serum leptin and insulin were determined by immunoassays at baseline and at the end of the treatment.

RESULTS

A significant association between serum leptin levels and the stage of hepatic fibrosis was noted; patients with cirrhosis presented higher serum leptin levels compared to those with lower fibrosis stage [CHB patients (17436 pg/ml vs 6028.5 pg/ml, p = 0.03), CHC patients (18014 pg/ml vs 4385 pg/ml, p = 0.05]. An inverse correlation between lower leptin levels and response to lamivudine monotherapy was noted in patients with CHB; those with a virologic response presented lower serum leptin levels (5334 vs 13111.5 pg/ml; p-value = 0.003) than non-responders. In genotype 1 CHC patients, insulin resistance played a significant role in the response to antiviral therapy.

CONCLUSION

Our data clearly suggest that cirrhosis due to CHB or CHC is associated with higher leptin levels. Increased serum leptin levels represent a negative prognostic factor for response to lamivudine monotherapy in patients with CHB. In CHC patients insulin resistance strongly influences the response to antiviral treatment in patients infected with genotype 1.

The levels of ghrelin, leptin, TNF-alpha, and IL-6 in liver cirrhosis and hepatocellular carcinoma due to HBV and HDV infection

Background/Aim. Malnutrition, a common problem in liver cirrhosis and HCC, may readily deteriorate the clinical functions with resultant poor prognosis. Beside the hyper catabolic state frequently encountered in chronic liver disease and HCC, anorexia and reduced food intake also worsen the malnutrition. The recently discovered peptide hormone ghrelin acts as a counterpart of leptin in regulation of food intake and fat utilization. The aim of the present study was to investigate the ghrelin and leptin levels in cirrhosis and HCC due to hepatitis B and D viruses, and the association of ghrelin and leptin with TNF-α, IL-6 and the severity of the disease. Materials and methods. We measured serum ghrelin, leptin, TNF-α, and IL-6 levels using specific immunoassay in 45 patients (23 cirrhosis, 22 HCC) with HBV and/or HDV and in 25 control subjects. Results. In comparison to controls, serum ghrelin, TNF-α, and IL-6 levels were significantly higher in cirrhosis and HCC (P < .05), whereas serum leptin levels were found decreased (P < .05). There was a positive correlation between ghrelin and TNF-α, and a negative correlation between leptin and TNF-α (P < .05). Conclusion. In cirrhosis and HCC due to HBV or HDV, serum ghrelin levels were increased with a corresponding decrease in serum leptin concentrations, acting as a physiological counterpart of ghrelin. The increasing of ghrelin is more prominent in Child C cirrhosis and the level was correlated with TNF-α. The presence of nutritional and metabolic abnormalities, including malnutrition, in cirrhosis and HCC may, at least partly, elucidate high ghrelin and low leptin levels.

Altered postprandial glucose, insulin, leptin, and ghrelin in liver cirrhosis: correlations with energy intake and resting energy expenditure

BACKGROUND

Liver cirrhosis is associated with reduced energy intake and increased resting energy expenditure.

OBJECTIVE

We aimed to investigate the possible role of glucose, insulin, leptin, and ghrelin in the pathogenesis of these alterations.

DESIGN

Nutritional status, energy intake, resting energy expenditure, and fasting glucose, insulin, and leptin were assessed in 31 patients with cirrhosis. Postprandial glucose, insulin, C-peptide, leptin, and ghrelin responses were studied in a subgroup of patients after a standard meal. Ten healthy subjects served as controls.

RESULTS

Patients with cirrhosis had a lower energy intake (P < 0.05), higher resting energy expenditure (P < 0.05), higher fasting leptin (P < 0.05), and higher insulin resistance (P < 0.001) than did the healthy control subjects. In the patients with cirrhosis, fasting leptin was negatively correlated with resting energy expenditure (r = -0.38, P < 0.05) but not with energy intake. In control subjects, leptin was negatively correlated with energy intake (r = -0.72, P < 0.05) but not with resting energy expenditure. The patients with cirrhosis had higher postprandial glucose (P < 0.001) and lower ghrelin (P < 0.05) concentrations at 4 h postprandially than did the control subjects. The increase in ghrelin from its minimal postmeal value to 4 h postmeal was negatively correlated (r = -0.66, P = 0.014) with weight loss in the patients with cirrhosis. Energy intake was negatively correlated (r = -0.42, P < 0.01) with the postprandial increase in glucose.

CONCLUSIONS

In cirrhosis, altered postprandial glucose and ghrelin are associated with reduced energy intake and weight loss, respectively, and the effects of leptin on energy intake and expenditure seem to be altered. Insulin resistance might be involved in these altered postprandial responses.

Clinical significance of serum leptin, vascular endothelial growth factor and alpha-fetoprotein expression in hepatocelluar carcinoma

AIM: To explore the expression of serum leptin (Lep), vascular endothelial growth factor (VEGF) and alpha-fetoprotein (AFP) and their clinical significances in hepatocelluar carcinoma (HCC).

METHODS: Enzyme-linked immunosorbent assay (ELISA) was used to detect serum Lep, VEGF and AFP levels in 146 patients with HCC, 31 patients with liver cirrhosis and 30 healthy controls. The correlations Lep, VEGF, and AFP expression with clinical indexes were analyzed.

RESULTS: The serum Lep level was correlated with body mass index (BMI) in HCC patients (r = 0.64, P < 0.01), and significantly lower than that in cirrhotic patients and healthy controls (19 μg/L vs 35, 27 μg/L, P < 0.05). The serum Lep level in HCC patients was significantly decreased with upgrade of TNM stages, metastasis and recurrence (P < 0.05). In comparison with that in cirrhotic patients and healthy controls, the serum VEGF level in HCC patients was significantly increased (398 ng/Lvs 179, 167 ng/L, P < 0.01). There was no correlation between VEGF and AFP expression. The sensitivity and specificity of VEGF were 71.2% and 80.6%, and those of AFP were 73.3% and 83.9%, respectively, in the diagnosis of HCC. However, the sensitivity was increased to 91.8%, while the accuracy reached 90.4% after the combined detection of VEGF and AFP was used. There was a relationship beween the level of serum VEGF and tumor size (<3 cm: 237 ± 96 ng/L, >3 cm: 398 ± 124 ng/L, P < 0.01). As compared with that of TNMⅠ, Ⅱ stage, the serum VEGF of TNM Ⅲ, Ⅳstage was obviously higher (346 ± 131, 401 ± 152 ng/L vs 228 ± 89, 259 ± 102 ng/L, P < 0.01), and it also showed a significant elevation in the patients with metastasis and recurrent HCC (P < 0.01).

CONCLUSION: Nutrition status and prognosis of patients with HCC can be judged by serum Lep level, and the combined detection of serum VEGF and AFP may provide a significant marker for HCC diagnosis and prognosis.

Leptin in the field of hepatic fibrosis: a pivotal or an incidental player?

Leptin is a 16-kDa nonglycosylated protein primarily secreted from the adipocytes of white fat; minor levels of regulated leptin expression also occurs at other sites such as placenta, skeletal muscle, the stomach fundus, and culture-activated hepatic stellate cells (HSCs). Leptin is primarily involved in the regulation of food intake and body composition through a central feedback mechanism linking food ingestion, hypothalamus, and adipose tissue mass. In recent years, however, emerging evidence has suggested a critical role of leptin in hepatic inflammation and fibrogenesis and the influence of leptin on chronic liver disease has been an area of active research worldwide. In this review the data on the in vivo and in vitro actions of leptin on liver cells in experimental animal models of liver injury and the effects of leptin on human liver are discussed, with a focus on three distinct fields of chronic liver diseases: nonalcoholic steatohepatitis, alcoholic liver disease, chronic viral hepatitis, and, especially, hepatitis C.

Leptin and insulin response to long-term total parenteral nutrition depends on body fat mass

BACKGROUND & AIMS

Circulating leptin and insulin concentrations are physiologically representing energy homeostasis. However, the artificial situation of long-term total parenteral nutrition (TPN) and its effects on serum leptin and insulin is not fully understood.

METHODS

We studied 42 gastroenterological patients who received TPN for 19+/-11 days. Serum leptin and insulin levels as well as body composition assessed by bioelectrical impedance analysis were evaluated on days 0, 7 and 14. Insulin sensitivity was estimated by calculating the QUICKI.

RESULTS

Before the start of TPN, leptin correlated positively with female gender (P<0.03), BMI (P<0.02), fat mass (P<0.02), insulin levels (P<0.001) and QUICKI (P<0.001). Within the first week of TPN, an increase of leptin levels was found only in patients with a body fat mass of >30% (P<0.02). As these were predominantly women, their leptin levels increased likewise (P<0.003). In regression analysis, fat mass (P<0.001), female gender (P<0.04), insulin levels (P<0.03), and i.v. glucose supply rates (P<0.05) were independently associated to leptin levels.

CONCLUSIONS

TPN-especially glucose-induces a neurohumoral response as shown here for leptin and insulin that is mainly depending on the fat mass. Better understanding of this regulatory mechanism during artificial nutrition could offer a new approach to improve its therapeutic effects.

Glutamine-enriched total parenteral nutrition in patients with inflammatory bowel disease

BACKGROUND

Studies in animal models of inflammatory bowel disease (IBD) suggest that supplementation of total parenteral nutrition with glutamine (gln), a conditionally essential amino acid in catabolic conditions, increases gln plasma concentrations, reduces intestinal damage, improves nitrogen balance and may improve the course of the disease. However, human data supporting this assumption are missing.

METHODS

A total of 24 consecutive patients with an acute exacerbation of IBD (19 Crohn's disease; five ulcerative colitis) and scheduled for total parenteral nutrition (TPN) (>7 days) were randomised. Parallel to a standardised anti-inflammatory therapy, the patients received either a TPN with 1.5 g/kg body weight of a standard amino acid or an isonitrogenic, isocaloric TPN with 1.2 g/kg body weight of a standard amino acid and 0.3 g/kg L-alanine-L-glutamine. Primary end points were gln plasma concentrations and intestinal permeability assessed by urinary lactulose and D-xylose ratio.

RESULTS

Gln plasma levels did not differ significantly in either group throughout the study. Intestinal permeability did not change within 7 days either with or without gln supplementation (Delta-lactulose/xylose ratio: 0.01+/-0.05 (gln+) vs 0.02+/-0.1 (gln-)). The observed changes in inflammatory and nutritional parameters, and also disease activity, length of TPN and hospital stay, were independent of glutamine substitution. Five (41%) patients in the gln+ group and three (25%) patients in the gln- group needed surgical intervention.

CONCLUSION

Although limited by the sample size, these results do not support the hypothesis that glutamine substitution has an obvious biochemical or clinical benefit in patients with active IBD scheduled for total parenteral nutrition.

Different tumor necrosis factor-alpha-associated leptin expression in rats with dimethylnitrosamine and bile duct ligation-induced liver cirrhosis

Although serum leptin concentrations are reported by several studies to increase in patients with liver cirrhosis, the mechanisms underpinning this increase remain unclear. Circulating tumor necrosis factor alpha (TNF-alpha) concentrations are also recognized to increase in liver cirrhosis. Furthermore, TNF-alpha administration to rodents results in increased expression and secretion of leptin from adipose tissue in a manner dependent on type 1 TNF-alpha receptor (TNF-RI). The present study was undertaken to examine adipose leptin expression and to explore potential relationships between leptin expression and TNF-alpha in subjects with liver cirrhosis. Liver cirrhosis was induced in male Sprague-Dawley rats by dimethylnitrosamine (DMN) administration or by common bile duct ligation (BDL). Ad libitum and pair-fed animals constituted controls. Serum leptin and TNF-alpha concentrations were determined by immunoassay. Gene expression was determined by the reverse transcription-polymerase chain reaction, and protein levels were measured by Western blotting. Serum leptin values after adjustment of body fat mass in DMN-treated rats were significantly higher than in pair-fed or ad libitum groups. Leptin mRNA and protein levels in epididymal fat in DMN rats increased by 1.8-fold and 2.3-fold, respectively, as compared with ad libitum controls, and by 4-fold and 6-fold, respectively, as compared with the pair-fed group. Epididymal TNF-alpha and membranous TNF-RI (mTNF-RI) concentrations were both 2.3 times higher in DMN rats than in ad libitum controls but did not differ between ad libitum and pair-fed groups. Adipose leptin protein levels correlated directly with TNF-alpha and mTNF-RI concentrations in combined DMN, ad libitum, and pair-fed rats (r=0.64 and r=0.49, respectively; P<.05). In BDL-treated rats, however, serum and adipose leptin concentrations were identical to those in ad libitum controls despite 2.1-fold and 2.4-fold increase in epididymal TNF-alpha and mTNF-RI, respectively. TNF-alpha administration to fasting control animals increased serum and adipose leptin concentrations significantly. The observed TNF-alpha-associated leptin up-regulation in DMN-induced, but not in BDL-induced, cirrhotic rats is consistent with distinctly different roles for TNF-alpha in rats with nonbiliary, as opposed to biliary, cirrhosis.

Free and bound plasma leptin in normal weight and obese men and women: relationship with body composition, resting energy expenditure, insulin-sensitivity, lipid profile and macronutrient preference

OBJECTIVE

The adipose-borne hormone leptin circulates in free and protein-bound forms but little information is available about their biological significance. Free leptin (FL) levels are related to changes in fat mass, whereas bound leptin (BL) appears to be associated with resting energy expenditure (REE). Our aim was to assess FL and BL levels in normal weight and obese subjects and correlate them with metabolic and nutritional variables.

DESIGN AND PATIENTS

The partitioning of plasma leptin between FL and BL was evaluated in a population (n = 44) including both genders and different degrees of adiposity [body mass index (BMI) range 18.6-79.6 kg/m2].

MEASUREMENTS

Total leptin and FL and BL concentrations were measured by fast protein liquid chromatography (FPLC) followed by radioimmunoassay (RIA). Body composition, REE, insulin sensitivity, lipid parameters associated with cardiovascular risk and macronutrient preference were also assessed.

RESULTS

The BL/FL ratio was significantly reduced in obese subjects due to a major increase in FL compared with BL. Consequently, the gender difference of the %BL/%FL ratio present in lean subjects (35/65 in women; 65/35 in men) was lost in obese subjects. REE was negatively correlated with total leptin (P < 0.0001) and %FL (P < 0.0001), and positively with %BL (P < 0.001). Total leptin and FL were correlated with the diet carbohydrate content in all subjects.

CONCLUSIONS

FL increases with the amount of fat mass; the prevalence of FL in normal weight women in comparison to men suggests that this fraction is particularly linked to the amount of subcutaneous fat. Moreover, the correlation of BL with REE and the relationship of FL with food intake favours the view of different biological activities for the two circulating forms of leptin.

Child-Pugh classification dependent alterations in serum leptin levels among cirrhotic patients: a case controlled study

Background

As anorexia and hypermetabolism are common in cirrhosis, leptin levels may be increased in this disease. In this study, we investigated the relation between the severity of disease and serum leptin levels in post-hepatitis cirrhosis and the role of body composition, gender and viral aetiology of cirrhosis in this association.

Methods

Thirty-five cases with post-hepatitis cirrhosis and 15 healthy controls were enrolled in this study. Body composition including body mass index, body fat percentage and body fat mass were determined. Serum leptin levels were assayed.

Results

Leptin levels were significantly higher among cirrhotic patients independent of sex compared to controls (p = 0.001). Female patients in both groups have had higher leptin levels than males (in cirrhotics p = 0.029, in controls p = 0.02).

Cirrhotic patients in each of A, B and C subgroups according to the Child- Pugh classification revealed significantly different levels compared to controls (p = 0.046, p = 0.004, p = 0.0001, respectively). Male cirrhotics in Child-Pugh Class B and C subgroups had significantly higher leptin levels compared to male controls (p = 0.006, p = 0.008). On the other hand, female patients only in Child Pugh class C subgroup have had higher levels of serum leptin compared to controls (p = 0.022).

Child-Pugh classification has been found to be the sole discriminator in determination of leptin levels in cirrhotics by linear regression (beta: 0.435 p = 0.015).

Conclusion

Serum leptin levels increase in advanced liver disease independently of gender, body composition in posthepatitic cirrhosis. The increase is more abundant among patients that belong to C subgroup according to the Child- Pugh classification.

The severity of liver fibrosis is associated with high leptin levels in chronic hepatitis C

Recent attention has focused on the liver profibrogenic role of leptin in animal models. The purpose of this study was to evaluate the role of leptin and TNF-alpha in the severity of liver fibrosis in patients with chronic hepatitis C (CHC). We used a radioimmunoassay to determine serum leptin concentrations in 77 consecutive patients with CHC and 22 healthy controls. Leptin was correlated with liver histological (METAVIR) and metabolic indices. Sixty five patients had none to moderate liver fibrosis (F0-F2) and twelve severe fibrosis (F3-F4). Steatosis was observed in all but 27 patients. Leptin was significantly increased in patients compared with controls and was significantly more elevated in females both in patients and controls. The age, age at infection, prothrombin index, body mass index (BMI), triglycerides, glycaemia, ferritin, leptin and TNF-alpha, were associated with severe fibrosis. Steatosis was significantly more pronounced in patients with severe than those without or moderate fibrosis (P = 0.04). Only leptin was significantly and independently associated with severe fibrosis (OR = 1.2, CI 95%: 1.1-1.4, P = 0.03). Leptin was significantly associated with BMI (r = 0.64, P < 0.001) and glycaemia (r = 0.43, P < 0.001). Significant correlations were found between steatosis and BMI (r = 0.30, P < 0.01) and glycaemia (r = 0.30, P < 0.01). In patients with CHC and higher BMI and glycaemia levels, the severity of liver fibrosis is associated with serum leptin. TNF-alpha is a putative candidate involved in the mechanism.

Serum leptin levels correlate with hepatic steatosis in chronic hepatitis C

OBJECTIVES

Hepatic steatosis (HS) has been related to obesity and fibrosis in chronic hepatitis C (CHC). The aim of this study was to determine the role of leptin system in HS development.

METHODS

Patients (n = 131) with biopsy-proven CHC, positive HCV RNA, and raised ALT were enrolled. Body mass index, percentage of body fat by skin fold measurement, and bioelectrical impedance analysis was calculated and serum leptin concentration measured. Intrahepatic HCV RNA, HS, necroinflammatory activity, and fibrosis were determined in liver biopsy tissue.

RESULTS

HS was present in 63 patients (48.1%). Steatosis was evident in 32 of 91 patients (35.2%) infected with genotype 1 and in 22 of 27 patients (81.5%) with genotype 3a (p < 0.001). In patients infected by genotype 3a, HS correlated significantly with intrahepatic HCV RNA load (r = 0.78; p < 0.001). However, in genotype 1, HS was associated with host factors such as leptin, body mass index, percentage of body fat, and visceral obesity. Multivariate analysis showed genotype (OR = 11.54, 95% CI = 1.13-117.14, p = 0.038), leptin levels (OR = 1.09, 95% CI = 1.03-1.17, p = 0.008) and fibrosis (OR = 9.86, 95% CI = 2.11-5.86, p = 0.03) as independent variables of HS development.

CONCLUSIONS

Hepatic steatosis was related to genotype, fibrosis degree, and serum leptin levels. Genotype 3 seems to have a viral specific steatogenic effect. Leptin seems to be a link between obesity and steatosis development in CHC genotype 1-infected patients.

Increased intramyocellular lipid concentration identifies impaired glucose metabolism in women with previous gestational diabetes

Women with previous gestational diabetes (pGDM) are frequently insulin-resistant, which could relate to intramyocellular lipid content (IMCL). IMCL were measured with (1)H nuclear magnetic resonance spectroscopy in soleus (IMCL-S) and tibialis-anterior muscles (IMCL-T) of 39 pGDM (32 +/- 2 years, waist-to-hip ratio 0.81 +/- 0.01) and 22 women with normal glucose tolerance (NGT; 31 +/- 1 years, 0.76 +/- 0.02) at 4-6 months after delivery. Body fat mass (BFM) was assessed from bioimpedance analysis, insulin sensitivity index (S(I)), and glucose effectiveness (S(G)) from insulin-modified frequently sampled glucose tolerance tests. pGDM exhibited 45% increased BFM, 35% reduced S(I) and S(G) (P < 0.05), and 40% (P < 0.05) and 55% (P < 0.005) higher IMCL-S and IMCL-T, respectively. IMCL related to body fat (BFM P < 0.005, leptin P < 0.03), but only IMCL-T correlated (P < 0.03) with S(I) and glucose tolerance index independent of BMI. Insulin-resistant pGDM (n = 17) had higher IMCL-S (+66%) and IMCL-T (+86%) than NGT and insulin-sensitive pGDM (+28%). IMCL were also higher (P < 0.005, P = 0.05) in insulin-sensitive pGDM requiring insulin treatment during pregnancy and inversely related to the gestational week of GDM diagnosis. Thus, IMCL-T reflects insulin sensitivity, whereas IMCL-S relates to obesity. IMCL could serve as an additional parameter of increased diabetes risk because it identifies insulin-resistant pGDM and those who were diagnosed earlier and/or required insulin during pregnancy.

Prevention and treatment of progressive multiple organ disfunction in acute pancreatitis

Acute pancreatitis is illness with unpredictable outcome. In some patients course of illness is progressive and leading to multiple organ dysfunction syndrome often resulting with lethal outcome. During last decade the treatment protocols have changed. Basic patophysiologic mechanisms leading to progression of the illness, as well as, contemporary diagnostic and treatment possibilities that can prevent occurrence of severe consequences and improve outcome are presented.

Increased serum leptin concentrations correlate with soluble tumour necrosis factor receptor levels in patients with cirrhosis

OBJECTIVE

Several reports have documented the involvement of hyerleptinaemia in malnutrition associated with liver cirrhosis. However, the mechanisms of elevated leptin levels remains unclear. Serum concentrations of tumour necrosis factor-alpha (TNF-alpha), and two soluble TNF receptors (sTNF-RI and sTNF-RII) are increased in patients with liver cirrhosis. In rodents, administration of TNF-alpha has been shown to stimulate plasma leptin concentration, suggesting that a cytokine-leptin link may mediate anorexia and weight loss during chronic inflammation. In this study, we investigate the potential interaction of the TNF-alpha system with leptin in the development of malnutrition in liver cirrhosis.

STUDY DESIGN

A total of 26 male patients with liver cirrhosis and 25 healthy people were recruited at an outpatient clinic at the Veterans General Hospital in Taiwan. Serum biochemistry and anthropometric measurement by bioelectrical impedance analysis were used to assess nutrition status, and immunoassay was used to determine serum leptin, TNF-alpha sTNF-RI and sTNF-RII concentrations.

RESULTS

In cirrhotic patients, the body fat mass (FM) and serum albumin levels were both lower than control subjects [15.8 (13.2-19.5) kg vs. 18.9 (16.2-20.1) kg; 35 (33-41) g/l vs. 43 (41-45) g/l, respectively; P < 0.05]. Serum TNF-alpha sTNF-RI and sTNF-RII were significantly elevated in cirrhotic patients compared to healthy controls [9.8 (7.2-13.5) ng/l vs. 4.3 (3.4-7.3) ng/l; 1682.1 (1344.8-2179.4) ng/l vs. 1319.6 (1037.7-1632.1) ng/l; 4462.2 (3748.5-5159.4) ng/l vs. 3559.8 (2506.9-3988.9 ng/l, respectively; P < 0.01] and correlated with disease severity (graded by Pugh-Child's scores). An inverse correlation was observed between circulating sTNF-RI and sTNF-RII to serum albumin levels (r =-0.42, r = -0.398; P < 0.05). The serum leptin levels in cirrhotic patients were significantly higher [6.0 (3.6-7.7) (g/l vs. 3.4 (2.9-4.3) (g/l; P < 0.01) and correlated with body FM (r = 0.52; P < 0.01]. Using a multiple linear regression analysis with leptin as dependent variable and FM and TNF-alpha, sTNF-R as independent variables, FM and serum sTNF-RI concentrations were found to predict independently the leptin levels in cirrhotic patients.

CONCLUSION

Our study demonstrated that serum levels of TNF-alpha, sTNF-RI, sTNF-RII and leptin were all elevated in cirrhotic patients. The severity of liver cirrhosis was an important factor for the activation of TNF-alpha system. The activated TNF-alpha system conjointly with hyperleptinaemia might mediate malnutrition in patients with liver cirrhosis.

Serum leptin in NASH correlates with hepatic steatosis but not fibrosis: a manifestation of lipotoxicity?

Nonalcoholic steatohepatitis (NASH) is a disorder characterized by hepatic steatosis, inflammation, and fibrosis. Leptin is an adipocyte-derived antiobesity hormone that in rodents prevents "lipotoxicity" by limiting triglyceride accumulation and also regulates matrix deposition (fibrosis) during wound healing. We therefore determined serum leptin levels in patients with NASH to determine whether relationships existed between leptin levels and severity of hepatic steatosis or fibrosis. We used a radioimmunoassay to determine serum [total] leptin concentrations in 27 men and 20 women with NASH and 47 controls matched for gender and body mass index (BMI; and partly for age). Serum leptin values were correlated with hepatic steatosis, fibrosis, and inflammation (each categorized semiquantitatively on liver histology), and with anthropometric indices, serum lipids, glucose, insulin, c-peptide, and alanine aminotransferase (ALT) levels. Compared with the controls, mean serum leptin levels were raised in both men and women with NASH (men 14 +/- 11 ng/mL vs. 7.2 +/- 4.1 ng/mL, P =.003; women 35 +/- 16 ng/mL vs. 15 +/- 8.2 ng/mL, P <.001). Leptin values correlated with serum c-peptide levels but not with BMI. In a multivariate analysis, serum leptin (P =.027), serum c-peptide (P =.001), and age (P =.027) were selected as independent predictors of the severity of hepatic steatosis. However, serum leptin was not an independent predictor of hepatic inflammation or fibrotic severity. In conclusion, hyperleptinemia occurs in NASH and is not explained simply by gender, obesity, or the presence of type 2 diabetes. Furthermore, leptin levels correlate directly with the severity of hepatic steatosis but not with inflammation or fibrosis. We propose that the relationship between leptin and steatosis reflects a pathogenic role of leptin in hepatic insulin resistance and/or a failure of the antisteatotic actions of leptin ("peripheral leptin resistance").

Nutritional aspects of liver disease and transplantation

In the past year, some relevant papers related to the diagnosis of malnutrition and its pathogenesis in cirrhosis have been published. The value of anthropometrics in the nutritional assessment of end-stage cirrhotic patients has been reinforced. Also, the role of bioelectrical impedance analysis in these patients has been redefined. Several papers have investigated the relationship between leptin and malnutrition in chronic liver disease, particularly the role of alcoholism in hyperleptinaemia, and the importance of protein-bound leptin in these patients. In other papers, the impact of both undernutrition and obesity on the outcome of liver transplantation has been investigated. Two randomized, controlled trials on enteral nutrition in liver disease have been published in this period. One of them deals with a clinical situation (i.e. severe alcoholic hepatitis) associated with a high mortality rate, whereas the second is the first controlled trial in the field of preoperative nutrition in liver transplantation. Finally, some papers provide further arguments in the dilemma of which route of nutrition (enteral or parenteral) is better in cirrhosis.