Oxidative stress and thyroid hormones in patients with liver diseases

Potential mechanisms of traditional Chinese medicine in the treatment of liver cirrhosis: a focus on gut microbiota

Cirrhosis, a pathological stage that develops from various chronic liver diseases, is characterized by liver fibrosis, pseudolobular formation, and chronic inflammation. When it progresses to the decompensated phase, the mortality rate of cirrhosis can reach 80%. The role of gut microbiota in the progression of liver diseases has received significant attention. Numerous studies have shown that regulating gut microbiota has significant therapeutic effects on preventing and reversing liver cirrhosis. This article reviewed the mechanisms by which gut microbiota influence liver cirrhosis, explaining the effective therapeutic effects of traditional Chinese medicine. Through multi-directional regulation involving signaling pathways, gut microbiota diversity, and restoration of intestinal barrier function, traditional Chinese medicine has been promising in ameliorating liver cirrhosis, providing treatment options and pharmacological guidance for the occurrence and development of liver cirrhosis.

Thyroid hormone profile is related to prognosis in acute decompensation of cirrhosis

OBJECTIVE

To investigate the prognostic significance of thyroid hormone profile in patients hospitalized for decompensated cirrhosis.

SUBJECTS AND METHODS

Prospective cohort study that included 119 subjects. All subjects were evaluated at admission and followed for 90 days. TSH, fT3, fT4 were measured within 24 hours of hospitalization.

RESULTS

Higher fT4 and lower fT3 levels were observed among Child-Pugh C patients as compared to Child-Pugh A and B, and in those with acute-on-chronic liver failure (ACLF). Lower fT3/fT4 ratio was observed in those with ascites, infections, ACLF, and in Child-Pugh C. Ninety-day mortality was 26.9% and it was independently associated with higher Model for End-stage Liver Disease (MELD) and TSH, and lower fT3/fT4 ratio in multivariate analysis. A new prognostic model including MELD, TSH and fT3/fT4 ratio was devised. The areas under the receiver operating characteristic curves for MELD, fT3/fT4 ratio, TSH (μIU/mL), and the new model for predicting 90-day mortality were 0.847 ± 0.041, 0.841 ± 0.039, 0.658 ± 0.062, and 0.899 ± 0.031, respectively. The 90-day survival was 31.6% in patients with values of the predictive model ≥ -0.77 and 93.5% for values < -0.77 (P < 0.001).

CONCLUSIONS

Thyroid hormone profile was strongly associated with worse outcomes in patients with cirrhosis and might represent promising prognostic tools that can be incorporated in clinical practice.

Assessment of thiol-disulfide and glutathione homeostasis after levothyroxine replacement in individuals with autoimmune or nonautoimmune hypothyroidism

OBJECTIVE

Thyroid hormones are known to affect the biosynthesis and degradation of antioxidant compounds, suggesting a possible link between hypothyroidism and oxidative stress. However, there is no clear consensus in the literature regarding this association. The aim of this study was to evaluate oxidative stress markers (extracellular thiol-disulfide homeostasis and intracellular glutathione homeostasis) in patients with hypothyroidism due to autoimmune (Hashimoto's thyroiditis) or nonautoimmune thyroid disease rendered euthyroid after levothyroxine replacement.

SUBJECTS AND METHODS

The study included 116 patients admitted to the Taksim Training and Research Hospital (Istanbul, Türkiye). Of these, 50 had hypothyroidism due to Hashimoto's thyroiditis (HT group), 30 had nonautoimmune hypothyroidism (NAIH group), and 36 were healthy controls (control group). All participants were women. Extracellular thiol-disulfide homeostasis and intracellular glutathione homeostasis tests were assessed as oxidative stress markers.

RESULTS

Thiol-disulfide homeostasis in both HT and NAIH groups was shifted toward the oxidative spectrum. Compared with the control group, the HT and NAIH groups had lower levels of native (p < 0.001 and p = 0.001, respectively) and total (p = 0.002 and p = 0.012, respectively) thiol, as well as a lower native thiol/total thiol ratio (p < 0.001 for both). The HT group also had higher disulfide levels than the control group (p = 0.027). Reduced glutathione (GSH) and oxidized glutathione (GSSG) values were comparable across all three groups, but the HT and NAIH groups had higher GSSG/GSH (p < 0.001 for both) and GSSG/(GSH+GSSG) ratios (p = 0.003 and p = 0.005, respectively), along with lower GSH/(GSH+GSSG) ratio (p = 0.001 and p = 0.002, respectively) than the control group.

CONCLUSION

Levothyroxine replacement was ineffective in ameliorating oxidative stress in patients with hypothyroidism due to Hashimoto's thyroiditis or nonautoimmune causes, as extracellular thiol-disulfide homeostasis was notably altered in these patients compared with healthy controls. The findings of this study suggest that oxidative stress remains a prevailing issue in patients with autoimmune or nonautoimmune hypothyroidism even after euthyroidism is restored.

Liposome cocktail activator modulates hepatocytes and remodels the microenvironment to mitigate acute liver failure

Acute liver failure (ALF) is a mortal and critical hepatic disease, in which oxidative stress, inflammation storm and hepatocyte death are crucial in the pathogenesis. Hence, in contrast to the control of a single link, a combination therapy targeting multiple pathogenic links of the disease will be a favorable means to control the progression of the disease. In this study, we constructed dimethyl itaconate-loaded liposomes modified with dodecyl gallate as a cocktail activator to investigate its functional role in acetaminophen (APAP)-induced ALF. Our results demonstrated that the cocktail activator acted on hepatocytes and triggered cocktail efficacy, thereby simultaneously attenuating APAP-induced hepatocyte damage and remodeling the damage microenvironment. The cocktail activator could effectively scavenge reactive oxygen species, inhibit excessive inflammatory responses and reduce cell death in impaired hepatocytes for detoxification. More importantly, the cocktail activator could remodel the damage microenvironment, thus further promoting hepatocyte expansion and specifically switching macrophages from the M1 to M2 phenotype for a favorable liver regeneration of ALF. Furthermore, in APAP-induced ALF mouse model, the cocktail activator improved liver function, alleviated histopathological damage and increased survival rate. In summary, these findings indicate that the cocktail activator may provide a promising therapeutic approach for ALF treatment as a nanomedicine.

Influence of Altered Thyroid Hormone Mechanisms in the Progression of Metabolic Dysfunction Associated with Fatty Liver Disease (MAFLD): A Systematic Review

We performed a systematic review of the mechanisms of thyroid hormones (THs) associated with metabolic dysfunction associated with fatty liver disease (MAFLD). This systematic review was registered under PROSPERO (CRD42022323766). We searched the MEDLINE (via PubMed) and Embase databases from their inception to March 2022. We included studies that assessed thyroid function by measuring the serum level of THs and those involved in MAFLD. We excluded reviews, case reports, editorials, letters, duplicate studies and designed controls. Forty-three studies included MAFLD, eleven analyzed THs, and thirty-two evaluated the mechanisms of THs in MAFLD. Thyroid hormones are essential for healthy growth, development and tissue maintenance. In the liver, THs directly influence the regulation of lipid and carbohydrate metabolism, restoring the homeostatic state of the body. The selected studies showed an association of reduced levels of THs with the development and progression of MAFLD. In parallel, reduced levels of T3 have a negative impact on the activation of co-regulators in the liver, reducing the transcription of genes important in hepatic metabolism. Overall, this is the first review that systematically synthesizes studies focused on the mechanism of THs in the development and progression of MAFLD. The data generated in this systematic review strengthen knowledge of the impact of TH changes on the liver and direct new studies focusing on therapies that use these mechanisms.

Cause-and-effect relationship between thyroid and liver diseases

Thyroid gland (TG) and the liver are in a complex relationship in both physiological and pathological conditions. Thyroid hormones accelerate metabolic processes, intensify the synthesis of proteins and vitamins, play an important role in the development and differentiation of all cells, including hepatocytes. In addition to the central role in the deiodination of thyroid hormones with the formation of their more active and inactivated forms, the liver also carries out their transport. Dysfunction of TG can lead to changes in liver function, and in liver diseases, abnormalities in the metabolism of thyroid hormones can occur. Most often, liver pathology in diseases of TG is manifested by an increase in the serum activity of enzymes of cytolysis and/or cholestasis. Changes in liver function tests are often observed in patients with thyrotoxicosis. They are based on oxidative stress or cholestasis. The increased activity of osteoblasts in hyperthyroidism leads to an increase in the bone fraction of alkaline phosphatase, which must be taken into account in the differential diagnosis. Hepatotoxicity of thyreostatic drugs is relatively common, ranging from minimal hepatocellular damage to fulminant liver failure. In the case of hypothyroidism, the pathophysiological mechanisms are mainly represented by lipid metabolism disorders leading to fatty degeneration. It should be remembered that severe hypothyroidism can be manifested by hyperammonemia and edematous-ascitic syndrome, requiring differential diagnosis with liver failure. Treatment of liver pathology in TG diseases includes normalization of thyroid status, and in cases of drug hepatitis – temporary withdrawal of a potentially hepatotoxic drug. The data on the association of hypothyroidism and non-alcoholic fatty liver disease in the aspect of developing new therapies are very interesting.

Antioxidant Potential of Parsley Leaf (Petroselinum crispum) Essential Oil on Hypothyroidism and Testicular Injury in Mice Intoxicated by Carbon Tetrachloride

The aim of the present study was to investigate the ameliorative potential of parsley (Petroselinum crispum) leaf essential oil (PO) against the detrimental effects of carbon tetrachloride (CCl₄) on the thyroid gland and testes of mice. Twenty-four adult male mice were divided into four groups and treated for 4 weeks. The 1^st control group received 3 mL/kg olive oil intraperitoneally, twice a week followed by 0.5 mL/kg saline intragastrically daily. The 2^nd CCl₄ group received CCl₄ (3 mL/kg intraperitoneally, twice a week). The 3^rd PO group received PO (0.5 mL/kg intragastrically daily), while the 4^th CCl₄+PO group received CCl₄ coadministrated with PO at the aforementioned doses. CCl₄ group recorded significant (p < 0.05) reduction in the activities of antioxidant enzyme catalase (CAT) and superoxide dismutase (SOD) and significant (p < 0.05) increase in the lipid peroxidation end product's level malondialdehyde (MDA) in the testes and thyroid glands. Meanwhile, serum levels of testosterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and thyroid hormones (thyroid-stimulating hormone (TSH), total triiodothyronine (T3), free triiodothyronine (fT3), total thyroxine (T4), and free thyroxine (fT4)) significantly decreased. Also, histopathologically, the testicular tissue showed hypospermatogenesis within irregular-shaped seminiferous tubules with prominent edema in the interstitial spaces confirming the aforementioned biochemical alterations. Treatment with PO significantly reduced the testicular and thyroid oxidative stress (p < 0.05) and elevated the testosterone (73.47%), FSH (92.11%), LH (33.33%), T3 (23.47%), fT3 (39.13%), T4 (27.91%), and fT4 (75%) as compared to that of CCl₄-treated group corresponding values. The PO GC/MS analysis indicated bioactive monoterpenes (major component is 1,3,8-mentha triene 34.48%) and phenylpropenes (major component is myristicin 21.04%). Results suggested the ameliorative effect of PO against CCl₄-induced hypogonadism in mice by suppressing oxidative stress and maintaining thyroid gland function.

Effect of acute and chronic liver diseases on the thyroid function in children

BACKGROUND

Thyroid hormones modulate hepatic function through regulation of basal metabolic rate in addition; the liver metabolizes the thyroid hormones and regulates their endocrine effects.

OBJECTIVES

To assess thyroid functions in children with acute and chronic liver diseases.

METHODS

85 studied children were divided into 4 groups; group 1 (20 children) with acute hepatitis (AH), group 2 (20 children) chronic liver disease1 (CLD1; relatively preserved liver functions including Child-Pugh stage A), group 3 (20 children) chronic liver disease2 (CLD2; includes Child-Pugh stage B or C), group 4 (25 children) controls. All groups were subjected to detailed history, physical examination, Complete blood count, liver, renal function tests, viral markers, and thyroid functions (FT3, FT4, TSH).

RESULTS

Free T3 levels were lower in children with AH, CLD1 and CLD2. There was significant increase in TSH serum levels in CLD2.In acute hepatitis a negative correlation between serum free T4 and AST (r = -0.991), positive correlation between serum TSH and AST, VLDL, and cholesterol levels (r= 0.503, 0.533 and 0.498). A positive correlation between free T3 levels and prothrombin concentration (r= 0.991). Negative correlations between free T3 levels and PT, serum bilirubin and LDL serum levels in children with CLD2 (r= -0.992) (r= -0.902) and (r= -0.946) CONCLUSION: Acute and chronic liver diseases affect thyroid function in children and is correlated with the disease severity.

A dopamine-precursor-based nanoprodrug for in-situ drug release and treatment of acute liver failure by inhibiting NLRP3 inflammasome and facilitating liver regeneration

Acute liver failure (ALF) is a severe liver disease with high mortality rate. Inflammasome is a newly-found and promising target for effective treatment of immunity-associated diseases including liver disease, and dopamine has recently been proved as an inhibitor for NLRP3 inflammasome. This work demonstrates a diselenide-based nanodrug for ALF treatment through inhibiting NLRP3 inflammasome activation and enhancing liver regeneration. A diselenide-containing molecule (DSeSeD) has been synthesized via covalently linking two l-Dopa molecules to a diselenide linker, and the resultant molecules form stable nanoparticles in aqueous media and encapsulate SW033291 (an inhibitor of prostaglandin-degrading enzyme that hampers liver regeneration) to produce the nanodrug (SW@DSeSeD). As a nanoscale prodrug, SW@DSeSeD protects its payloads from decomposition in bloodstream upon administration, accumulates in liver of ALF mice, then responds to the overexpressed ROS and thereby releases SW033291 as well as a stable dopamine precursor that can transform into dopamine in hepatic cells, thus achieving significant therapeutic efficacy against ALF through inhibiting NLRP3 inflammasome activation and enhancing hepatic regeneration. Moreover, multiple contrast agents have been loaded onto the nanodrug to achieve fluorescence, optoacoustic and magnetic resonance imaging for nanodrug location and disease evaluation.

Hypothyroidism-Induced Nonalcoholic Fatty Liver Disease (HIN): Mechanisms and Emerging Therapeutic Options

Nonalcoholic fatty liver disease (NAFLD) is an emerging worldwide problem and its association with other metabolic pathologies has been one of the main research topics in the last decade. The aim of this review article is to provide an up-to-date correlation between hypothyroidism and NAFLD. We followed evidence regarding epidemiological impact, immunopathogenesis, thyroid hormone-liver axis, lipid and cholesterol metabolism, insulin resistance, oxidative stress, and inflammation. After evaluating the influence of thyroid hormone imbalance on liver structure and function, the latest studies have focused on developing new therapeutic strategies. Thyroid hormones (THs) along with their metabolites and thyroid hormone receptor β (THR-β) agonist are the main therapeutic targets. Other liver specific analogs and alternative treatments have been tested in the last few years as potential NAFLD therapy. Finally, we concluded that further research is necessary as well as the need for an extensive evaluation of thyroid function in NAFLD/NASH patients, aiming for better management and outcome.

The effect of additive containing an organic form of iodine on the physiological-biochemical parameters of the body of cows

Iodine deficiency in soil and water in many countries leads to its low content in plants and animal feed produced from them. The limited intake of this element in animals can lead to endemic diseases. The lack of iodine in animal feeding is most often compensated for by the use of additives with an inorganic form of iodine, which can be poorly absorbed by the body. Feed products with an organic form of iodine have a great biological effect. A study on the effect of iodine-containing additives on the physiological and biochemical parameters of the animal organism was carried out on two groups of 15 cows. The experimental group was fed an organic form of iodine as part of the additive, the control group received an inorganic form of iodine. For all animals during the experiment the biochemical parameters of blood, milk productivity and reproductive ability were studied. During the experiment, an increase in metabolic and redox processes in the body was noted in the experimental group. An increase in mineral metabolism, including iodine content, was found. Due to the sufficient intake of organic iodine in the animals of the experimental group, there was an increase in the activity of the main hepatic enzymes AST and ALT. An increase in the process of gluconeogenesis due to an increase in the glucose content in the blood of experimental cows was revealed. An increase in milk production and reproductive function of animals of the experimental group was established. Within 30 days after the termination of feeding the supplement with the organic form of iodine in the experimental group, a prolonging effect was observed, consisting in higher values of blood biochemical parameters, improved reproductive function and milk productivity relative to equivalent animals in the control. As a result, it was concluded that the use of an additive with an organic form of iodine in the amount of 1.5 g in feeding cows for 60 days increases the iodine content in the blood serum of animals and increases the performance of all types of metabolism, which may indicate the best stimulating effect of the organic form of iodine on thyroid activity glands. This in turn helps to improve the productive and reproductive qualities of animals. To recommend the studied drug as a means to replenish iodine deficiency in animals and to more accurately analyze its effect on the hormone-forming function of the thyroid gland, it is necessary to study the level of thyroid hormones in the blood.

Thyroid hemodynamic alterations in Egyptian patients with sickle cell disease: relation to disease severity, total body iron and thyroid function

Background: Intraparenchymal thyroid Doppler measurements might be considered a useful index of the thyroid status as well as micro-circulation elsewhere in the body among sickle cell disease (SCD) patients. The authors aim to evaluate the intra-thyroidal hemodynamic changes and thyroidal volume in SCD patients and its relation to the disease severity, and thyroid functions tests as well as iron overload state. Methods: Sixty SCD patients, randomly recruited from the regular attendants of the Pediatric Hematology Clinic, Ain Shams University, Cairo, Egypt, were studied focusing on the disease duration, the transfusion history, the recorded Hydroxyurea, and chelation therapies and the vaso-occlusive crises history. Thyroid Doppler ultrasonography [Thyroid volume, Resistance index (RI) and pulsatility index (PI)] was performed and liver & cardiac MRI were assessed. Results: Thirteen (21.7%) of the SCD patients had hypothyroidism by thyroid function tests. SCD patients had significantly higher RI and PI values and a lower thyroid volume compared to the control group. No significant correlations were found between the thyroid functions tests and the thyroid Doppler parameters; a negative correlation of the disease duration to the thyroid volume and a positive one to RI & PI values were found. The mean serum ferritin did not significantly correlate to the thyroid Doppler indices nor did Liver and cardiac MRI results. Conclusion: The authors demonstrated an increased intra-thyroidal RI & PI and a decreased thyroid volume among SCD patients which might be related to impaired thyroidal microcirculation and vasculopathy rather than iron overload.

Interdependence of oxidative/antioxidant system indicators and thyroid status under conditions of prolonged exposure to small doses of radiation

We have studied the interdependence of the intensity of oxidative processes/antioxidant level and the thyroid status parameters in a group of students aged 18–24 who lived for a long time in the territory of enhanced radioecological control (density of soil contamination by isotopes (137Cs 3.7 ∙ 104 – 18.5 ∙ 104 Bq/m2). We examined 50 people from relatively environmentally friendly areas (control group) and 50 people from IV radiation zone (experimental group). In the experimental group, there were no individuals with clinical manifestations of thyroid pathology. However, subgroups with signs of hyperthyroidism and hypothyroidism were identified. We evaluated the level of cortisol, thyrotrophic hormone (TSH), triiodothyronine (T3), thyroxine (T4), malonic dialdehyde (MDA), ceruloplasmin (CP), transferrin (Tf), sulfhydryl groups (SH); we calculated the oxidative stress index (OSI). The research was conducted one month before the examination time and also during the exams as a factor in increased emotional stress. A lowered CP level was found in the subgroup with signs of hypothyroidism; SH groups – in all subgroups, separated by thyroid status. The oxidative stress index was higher in all students examined of the experimental group, compared with the control. The growth of MDA level is marked in the experimental group – it is the most strongly pronounced in conditions of additional emotional load in people with signs of hyperthyroidism and hypothyroidism. CP level significantly decreased in the subgroup of hyperthyroidism on the background of T3 decrease. OSI increased in all students examined from the experimental group. In the subgroup of hypothyroidism it became significantly higher than in the subgroup of euthyroidism. A positive correlation between the levels of CP and T3 was found. The highest values of the correlation coefficients were noted for subgroups with signs of hyperthyroidism and hypothyroidism, with the coefficient significance increasing under conditions of emotional stress. The index of oxidative stress in the experimental group positively correlated with the level of TSH – in terms of emotional stress, the statistical significance of the coefficients disappeared. In the subgroups divided by thyroid status, variability of interactions between OSI and T3 was observed but it was not statistically significant. It was found that the participation of thyroid status in supporting redox homeostasis in people aged 18–24 who suffered from chronic small-doze radiation exposure was realized mainly by the influence on the antioxidant system. The ability of thyroid hormones to maintain a proper antioxidant state was suppressed in this group. The unbalanced relationship between thyroid hormones and oxidative stress indicators is strongly manifested under conditions of additional emotional stress.

Association of non-alcoholic fatty liver disease with thyroid function: A systematic review and meta-analysis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases. The relationship of NAFLD with thyroid function parameters and hypothyroidism remains controversial.

AIM

To clarify the effect of thyroid function parameters and hypothyroidism on the development of NAFLD and progression to nonalcoholic steatohepatitis (NASH).

METHODS

PubMed, EMBASE, and Cochrane library databases were searched. Study quality was assessed. Weighted mean difference (WMD) and odds ratio (OR) with 95% confidence interval (CI) were calculated.

RESULTS

Twenty six studies involving 61,548 participants were eligible, most of which were of high quality. NAFLD/NASH patients had significantly higher TSH levels than controls in adults (NAFLD versus health: WMD = 0.105, 95%CI = 0.012-0.197; NAFLD versus euthyroidism: WMD = 0.100, 95%CI = 0.005-0.194; NASH versus NAFLD: WMD = 0.540, 95%CI = 0.136-0.944) and children/adolescents (NAFLD versus lean controls: WMD = 1.039, 95%CI = 0.104-1.973; NAFLD versus overweight/obese controls: WMD = 0.485, 95%CI = 0.267-.703). Unclassified hypothyroidism was positively associated with the risk of NAFLD/NASH in adults (NAFLD versus health: OR = 1.605, 95%CI = 1.180-2.183; NASH versus NAFLD: OR = 2.317, 95%CI = 1.425-3.768) and children/adolescents (NAFLD versus overweight/obese controls: OR = 2.015, 95%CI = 1.246-3.258). However, the statistical results were inconsistent among the subgroup meta-analyses of subclinical and overt hypothyroidism. Association of NAFLD with FT3 and FT4 levels was heterogeneous among population.

CONCLUSION

TSH level may be an important risk factor for the development and progression of NAFLD, independent of thyroid hormones.

Development and validation of a novel score for fibrosis staging in patients with chronic hepatitis B

BACKGROUND & AIMS

Non-invasive assessment methods for liver fibrosis are urgently needed. The present study aimed to develop a novel diagnostic model for fibrosis staging in patients with chronic hepatitis B.

METHODS

A cross-sectional set of 417 chronic hepatitis B patients who underwent liver biopsy was enrolled and the METAVIR score was adopted as the reference of fibrosis staging.

RESULTS

Among thyroid hormones, only the level of free tetraiodothyronine (FT4) decreased gradually with the METAVIR fibrosis score (P < .001). FibroStage, a novel diagnosis model that incorporates data on FT4, platelets, cholinesterase, gamma-glutamyl transpeptidase, and age, was developed using the deriving set (n = 219). For the diagnosis of significant fibrosis, the FibroStage model had a significantly higher area under the receiver operating curve than did the FibroIndex, Forn, and Lok models (all of P < .01) and tended to better than the fibrosis-4 (P = .0791) but comparable with the aspartate transaminase-to-platelet ratio index model (P = .1694). For the diagnosis of advanced fibrosis, FibroStage had a higher area under the receiver operating curve than did the aspartate transaminase-to-platelet ratio index, FibroIndex, Forn, and Lok models (all of P < .05) and had a comparable area under the receiver operating curve with the fibrosis-4 model (P = .2109). For the diagnosis of cirrhosis, the area under the receiver operating curve of FibroStage was higher than those of the aspartate transaminase-to-platelet ratio index, fibrosis-4, FibroIndex, and Lok (all of P < .05) models and was comparable with Forn (P = .1649). These results was validated by a validation set (n = 198).

CONCLUSION

FT4 may be an indicator for fibrosis staging in chronic hepatitis B patients. FibroStage is a better model than aspartate transaminase-to-platelet ratio index, fibrosis-4, FibroIndex, Forn, and Lok for the comprehensively diagnosis of significant and advanced fibrosis and cirrhosis.

Propranolol reduces systemic oxidative stress and endotoxemia in cirrhotic patients with esophageal varices

BACKGROUND

The aim of the study was to investigate the effect of propranolol on systemic oxidative stress and endotoxemia in patients with liver cirrhosis and clinically significant portal hypertension evidenced by the presence of esophageal varices.

METHODS

Fourteen patients with liver cirrhosis and esophageal varices, not previously been treated with non-selective beta-blockers (NSBB), were prospectively started on propranolol and followed up for three months. Serum early and late lipid peroxidation products (lipid hydroperoxides [LOOH] and malondialdehyde [MDA], respectively), and endotoxin concentrations in peripheral blood were measured. Fourteen age- and sex-matched healthy individuals were used as controls.

RESULTS

Patients with liver cirrhosis presented significantly higher systemic oxidative stress and endotoxin concentrations compared to healthy controls (P<0.001). Propranolol treatment for one month significantly reduced serum MDA (P<0.05), LOOH (P<0.01), and endotoxin levels (P<0.01) compared to pre-treatment values, whilst LOOH reached control levels. At three months of propranolol treatment, serum LOOH did not differ significantly from the one-month values, whilst serum endotoxin and MDA levels were further reduced between 3- and 1-month period (P<0.05 and P<0.01, respectively), with the latter reaching control levels. Amelioration of systemic endotoxemia at the one- and three-month follow-up intervals (compared to pre-treatment values) was not correlated with the respective reductions in serum MDA and LOOH.

CONCLUSIONS

This is the first study to show that NSBB treatment in liver cirrhosis exerts a significant systemic antioxidant action. This effect seems to be, at least partly, independent of their beneficial effects on intestinal barrier function and endotoxemia.

Nonalcoholic Fatty Liver Disease Is Not Associated with Thyroid Hormone Levels and Hypothyroidism: A Systematic Review and Meta-Analysis

BACKGROUND

Whether hypothyroidism is related to nonalcoholic fatty liver disease (NAFLD) is unclear. Thyroid dysfunction is closely related with components of metabolic syndrome. Given the hepatic manifestation of metabolic syndrome, several studies have investigated the association between NAFLD and thyroid dysfunction and have demonstrated inconsistent results. Thus, we conducted a systematic review and meta-analysis to better characterize the association between NAFLD and thyroid dysfunction.

METHODS

MEDLINE and Embase were searched through July 2016. The primary outcome was the association between NAFLD and subclinical, overt, and overall hypothyroidism. The secondary outcome was the difference in thyroid hormone levels (free triiodothyronine [FT₃], free thyroxine [FT₄], or thyroid-stimulating hormone [TSH]) between NAFLD patients and non-NAFLD controls. Pooled odds ratios (OR) and 95% CI were calculated using a random-effects model. All continuous data are summarized as the mean difference along with 95% CI.

RESULTS

Data were extracted from 14 studies involving 7,191 NAFLD patients and 30,003 controls. NAFLD was not associated with subclinical, overt, or overall hypothyroidism compared with non-NAFLD controls. Patients who had NAFLD did not show a significant difference in FT₃, FT₄, or TSH compared with non-NAFLD controls.

CONCLUSIONS

Our meta-analysis demonstrates no significant association between NAFLD and subclinical, overt, or overall hypothyroidism, and we also found no significant difference in thyroid hormone levels between participants with and without NAFLD.

Thyroid hormone suppresses expression of stathmin and associated tumor growth in hepatocellular carcinoma

Stathmin (STMN1), a recognized oncoprotein upregulated in various solid tumors, promotes microtubule disassembly and modulates tumor growth and migration activity. However, the mechanisms underlying the genetic regulation of STMN1 have yet to be elucidated. In the current study, we report that thyroid hormone receptor (THR) expression is negatively correlated with STMN1 expression in a subset of clinical hepatocellular carcinoma (HCC) specimens. We further identified the STMN1 gene as a target of thyroid hormone (T₃) in the HepG2 hepatoma cell line. An analysis of STMN1 expression profile and mechanism of transcriptional regulation revealed that T₃ significantly suppressed STMN1 mRNA and protein expression, and further showed that THR directly targeted the STMN1 upstream element to regulate STMN1 transcriptional activity. Specific knockdown of STMN1 suppressed cell proliferation and xenograft tumor growth in mice. In addition, T₃ regulation of cell growth arrest and cell cycle distribution were attenuated by overexpression of STMN1. Our results suggest that the oncogene STMN1 is transcriptionally downregulated by T₃ in the liver. This T₃-mediated suppression of STMN1 supports the theory that T₃ plays an inhibitory role in HCC tumor growth, and suggests that the lack of normal THR function leads to elevated STMN1 expression and malignant growth.

Correlation between vitamin D levels and apoptosis in geriatric patients infected with hepatitis C virus genotype 4

Background

Vitamin D levels play a pivotal role in most biological processes and differ according to age. A deficiency of vitamin D in chronic hepatitis C (CHC) patients has been shown to be linked with the severity of liver fibrosis, but little is known about the mechanism of this association.

Objective

In this study, we evaluate the potential interrelation between vitamin D levels, oxidative stress, and apoptosis, based on liver fibrosis in geriatric patients infected with hepatitis C virus (HCV) genotype 4.

Subjects and methods

A total of 120 adult individuals aged 30–68 years were recruited in this study. Of these, 20 healthy subjects (15 men and five women) with a mean age of 48.3±6.1 years were selected as controls, and 100 patients with a mean age of 47.8±4.9 years with chronic HCV (CHC) who had undergone liver biopsy (80 men and 20 women) were included in this study. Based on liver radiographic (computed tomography, magnetic resonance imaging) and histological Metavir system analyses, the CHC patients were classified into three groups: asymptomatic CHC carriers (n=30), fibrosis (n=25), and cirrhosis (n=45). HCV RNA, HCV genotypes, inflammatory cytokines AFP and TNFα, 25-hydroxyvitamin D (25[OH]D) levels, apoptotic markers single-stranded DNA (ssDNA) and soluble Fas (sFas), and oxidative stress markers nitric oxide (NO) and total antioxidant capacity (TAC) were estimated by using molecular, immunoassay, and colorimetric techniques.

Results

Approximately 30% of the study population (n=30) were diagnosed as asymptomatic CHC carriers, and 70% of the study population (n=70) had severe fibrosis; these were classified into fibrosis and cirrhosis. There was a significant reduction in 25(OH)D levels and TAC activity, along with an increase in levels of NO, AFP, TNFα, ssDNA, and sFas in fibrosis and cirrhosis subjects compared with those of asymptomatic CHC carriers and health controls. The deficiency in 25(OH)D levels correlated positively with sFas, ssDNA, AFP, TNFα, NO, and TAC, and negatively with age, sex, liver function, body mass index, homeostatic model assessment – insulin resistance, HCV RNA, and viral load. Significant intercorrelation was reported between serum 25(OH)D concentrations and apoptotic and oxidative markers, which suggested progression of liver pathogenesis and fibrogenesis via oxidative and apoptotic mechanisms.

Conclusion

The data showed that vitamin D status was significantly correlated with pathogenesis and fibrogenesis of the liver in geriatric patients infected with HCV genotype 4. The deficiency in 25(OH)D levels was shown to have a pivotal role in the pathogenesis of liver via apoptotic, oxidative stress, and inflammatory mechanistic pathways. The data point to adequate vitamin D levels being recommended for a good response to treatment strategies, especially in older CHC patients.

The influence of end-stage liver disease and liver transplantation on thyroid hormones

BACKGROUND

Thyroid dysfunction has been reported in most chronic illnesses including severe liver disease. These defects in thyroid hormone metabolism result in the sick euthyroid syndrome, also known as low T3 syndrome.

OBJECTIVES

Our objective was to evaluate the thyroid function in patients with end stage liver disease prior and after deceased donor liver transplantation and to correlate thyroid hormonal changes with the MELD score (Model for End stage Liver Disease).

METHODS

In a prospective study, serum levels of thyrotropin (thyroid stimulating hormone TSH), total thyroxine (tT4), free thyroxine (fT4) and triiodothyronine (T3) from 30 male adult patients with end stage liver disease were measured two to four hours before and 6 months after liver transplantation (LT). MELD was determined on the day of transplant. For this analysis, extra points were not added for patients with hepatocellular carcinoma.

RESULTS

The patients had normal TSH and fT4 levels before LT and there was no change after the procedure. Total thyroxine and triiodothyronine were within the normal range before LT, except for four patients (13.3%) whose values were lower. Both hormones increased to normal values in all four patients after LT (P=0.02 and P<0.001, respectively). When the patients were divided into two groups (MELD <18 and MELD >18), it was observed that there was no change in the TSH, freeT4, and total T4 levels in both groups after LT. Although there was no significant variation in the level of T3 in MELD <18 group (P=0.055), there was an increase in the MELD >18 group after LT (P=0.003).

CONCLUSION

Patients with end stage liver disease subjected to liver transplantation had normal TSH and fT4 levels before and after LT. In a few patients with lower tT4 and T3 levels before LT, the level of these hormones increased to normal after LT.

Liver Damage in Patients with HCV/HIV Coinfection Is Linked to HIV-Related Oxidative Stress

HIV infection aggravates the progression of liver damage in HCV-coinfected patients, with the underlying pathogenesis being multifactorial. Although high level of oxidative stress has been observed frequently in patients infected with HIV or HCV, the status of oxidative stress in HIV/HCV coinfection and its contribution to HCV liver damage have not been determined. This study involved 363 HBsAg-negative, anti-HCV-positive former blood donors recruited from a village in central China in July 2005; of these, 140 were positive for HIV. Of these 363 subjects, 282 were successfully followed up through July 2009. HIV/HCV-coinfected subjects had higher rates of end-stage liver disease-related death than those monoinfected with HCV. Liver ultrasound manifestations were poor in HIV-positive than in HIV-negative individuals, in both chronic HCV carriers and those with resolved HCV. Serum concentrations of total glutathione (tGSH), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), GSSG, and reduced GSH were higher in HIV-positive than HIV-negative subjects. GSSG concentrations were higher in HIV-infected subjects with abnormal ALT/AST levels than in those with normal ALT/AST levels and were associated with poorer liver ultrasound manifestations. These finding indicated that HIV infection accelerated HCV-associated liver damage in HIV/HCV-coinfected individuals. Increased oxidative stress, induced primarily by HIV coinfection, may contribute to aggravated liver damage.

Impact of hypothyroidism on the development of non-alcoholic fatty liver disease: A 4-year retrospective cohort study

Background/Aims

Hypothyroidism is reported to contribute to the development of nonalcoholic fatty liver disease (NAFLD). We compared the risk of the development of NAFLD among three groups with different thyroid hormonal statuses (control, subclinical hypothyroidism, and overt hypothyroidism) in a 4-year retrospective cohort of Korean subjects.

Methods

Apparently healthy Korean subjects without NAFLD and aged 20-65 years were recruited (n=18,544) at health checkups performed in 2008. Annual health checkups were applied to the cohort for 4 consecutive years until December 2012. Based on their initial serum-free thyroxine (fT4) and thyroid-stimulating hormone (TSH) levels, they were classified into control, subclinical hypothyroidism (TSH >4.2 mIU/L, normal fT4), and overt hypothyroidism (TSH >4.2 mIU/L, fT4 <0.97 ng/dL) groups. NAFLD was diagnosed on the basis of ultrasonography findings.

Results

NAFLD developed in 2,348 of the 18,544 subjects, representing an overall incidence of 12.7%: 12.8%, 11.0%, 12.7% in the control, subclinical hypothyroidism, and overt hypothyroidism groups, respectively. The incidence of NAFLD did not differ significantly with the baseline thyroid hormonal status, even after multivariate adjustment (subclinical hypothyroidism group: hazard ratio [HR]=0.965, 95% confidence interval [CI]=0.814-1.143, P=0.67; overt hypothyroidism group: HR=1.255, 95% CI=0.830-1.899, P=0.28).

Conclusions

Our results suggest that the subclinical and overt types of hypothyroidism are not related to an increased incidence of NAFLD.

Subclinical and clinical hypothyroidism and non-alcoholic fatty liver disease: a cross-sectional study of a random population sample aged 18 to 65 years

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is one of the most common disorders of the liver worldwide. Recently, a correlation between thyroid dysfunction and NAFLD has been discussed. Objective of the present study was to investigate the association between thyroid dysfunction and hepatic steatosis.

METHODS

Data from 2,445 subjects (51.7% females) aged 18 to 65 years participating in a population-based cross-sectional study were assessed based on a standardized questionnaire and documentation of physical, biochemical and ultrasonographic findings. After application of exclusion criteria, a total of 1,276 subjects were included in the study collective. The influence of potential factors on the development of hepatic steatosis was assessed using multivariate logistic regression.

RESULTS

The prevalence of hepatic steatosis in the study collective was 27.4% (n = 349). The serum thyroxin (TT4) concentration in subjects with hepatic steatosis was reduced (p =0.0004). Adjusting for age, or BMI, there was an increased prevalence of hepatic steatosis in subjects with reduced TT4 concentrations (p = 0.0143; p = < .0001).

CONCLUSIONS

The findings of the present study confirm an association between both subclinical and clinical hypothyroidism and hepatic steatosis.

Association between serum total antioxidant capacity and mortality in severe septic patients

PURPOSE

Total antioxidant capacity (TAC) in severe septic patients has been analyzed in few studies with limited number of subjects. In addition, no association between TAC serum levels and mortality in patients with sepsis has been investigated. We aimed at assessing a possible relationship between TAC serum levels and mortality using a large cohort of patients with severe sepsis.

METHODS

We performed an observational, prospective, multicenter study in 6 Spanish intensive care units. Serum levels of TAC were measured in a total of 213 patients with severe sepsis. End point was 30-day mortality.

RESULTS

Nonsurviving septic patients (n = 75) showed higher serum TAC levels (P = .006) than survivors (n = 138). Cox regression analysis showed that TAC serum levels were associated with 30-day survival (hazard ratio = 1.50, 95% confidence interval = 1.16-1.94, P = .002). Receiver operating characteristic analysis showed that the area under curve of TAC serum levels to predict 30-day survival was 0.61 (95% confidence interval = 0.545-0.680, P = .04).

CONCLUSIONS

The most relevant and new findings of our study, the largest cohort of septic patients providing data on circulating TAC levels so far, were that serum TAC levels are associated with mortality and could be used as biomarker to outcome prediction in severe septic patients.

Non-alcoholic fatty liver disease and thyroid dysfunction: a systematic review

Thyroid hormones are totally involved in the regulation of body weight, lipid metabolism, and insulin resistance. Therefore it is anticipated that thyroid hormones may have a role in the pathogenesis of non alcoholic fatty liver disease (NAFLD) and non alcoholic steatohepatitis (NASH). In this study, we reviewed the current literature on the association between thyroid dysfunction and NAFLD/NASH. A search for English language medical literature reporting an association between thyroid dysfunction and NAFLD/NASH in humans was conducted across PubMed, ISI Web of Science, and Scopus in August, 2013. Out of 140 studies initially identified through the search, 11 relevant articles were included in the final review. Thyroid dysfunctions in the form of overt or subclinical hypothyroidism are prevalent among patients with NAFLD/NASH. Hypothyroidism appears to be an independent risk factor for NAFLD/NASH in some studies; however, other newly published studies failed to find such an association. The results of the studies on the role of thyroid abnormalities in NAFLD/NASH are inconsistent, and further research is recommended to determine the relationship between hypothyroidism and NAFLD/NASH and the underlying mechanisms.

Could serum nitrate and nitrite levels possibly predict hepatorenal syndrome in hepatitis C virus-related liver cirrhosis?

PURPOSE

This study aimed to determine whether serum levels of nitric oxide metabolites (nitrates and nitrites) correlate with renal dysfunction in patients with liver cirrhosis and, moreover, to assess nitric oxide metabolite (NOx) power for predicting hepatorenal syndrome (HRS) in such patients.

METHODS

Among patients admitted to the Tropical Medicine Department, Ain Shams University Hospital, a total of 60 patients with chronic hepatitis C-related liver cirrhosis were included in this study. Patients were divided into three groups. Group I included 20 patients with compensated liver cirrhosis (CLC). Group II included 20 patients with decompensated liver cirrhosis (DLC). Group III included 20 patients with decompensated liver cirrhosis and HRS. Twenty healthy subjects with no clinical or laboratory evidence of liver disease were enrolled as a control group (group IV).

RESULTS

Patients with HRS had a higher mean nitrite levels followed by DLC, then CLC, and then controls. The sensitivity and specificity of NO metabolites (nitrites) were 100 % and 93.3 %, respectively, with accuracy of 95 % at cutoff value of 387 μmol/L for diagnosing patients with HRS. There was a highly significant statistical difference between patients positive and negative for nitrites as regards renal profile (p = 0.000).

CONCLUSION

A strong relation between nitrite cutoff value and renal dysfunction in liver cirrhosis has been found. Also, patients with HRS had higher mean serum nitrite levels than decompensated liver cirrhosis or compensated liver cirrhosis, raising the possibility of using nitrate and nitrite levels as a predictor for HRS in HCV-related liver cirrhosis.

The impact of high fat diets on physiological changes in euthyroid and thyroid altered rats

The association of adverse health with high fat intake has long been recognized. However, the lack of research focusing on the interrelationship of thyroid and liver function, and the pathogenesis of a high fat diet leaves these topics poorly understood. The objective of this study was to evaluate and compare the physiological changes in euthyroid and thyroid altered animal model fed saturated and unsaturated high fat diets. To achieve this objective adult male Sprague Dawley rats (n = 100) were fed one of five diets; a control or one of four test diets containing 25% saturated or unsaturated, and 37% saturated or unsaturated fats for a period of eight weeks. Each experimental group consisted of ten euthyroid and ten thyroid altered animals. An altered thyroid state was chemically induced with the addition of 0.05% propylthiouracil (PTU) in the drinking water. Euthyroid animals fed high fat diets increased in body weights and body lengths, compared to thyroid altered animals (P < 0.05). Alanine aminotransferase (ALT) and asparte aminotransferase (AST) levels increased across all experimental groups. HbA1C values and urinary glucose values were within normal range for all animals. Liver morphology showed increased hepatic stellate (ito) and vacuole cells in thyroid altered animals. These findings suggest that altered thyroid status negatively impacts growth and weight gain, and simultaneously affected lipid metabolism, resulting in abnormal liver morphology.

Thyroid hormone levels in children with liver cirrhosis awaiting a liver transplant

OBJECTIVES

Evidence exists that decreased in triiodothyronine (T3) and thyroxine (T4) levels are associated with the severity of liver disease, and these hormones could be used as disease prognostic factors, but there are paradoxes in this regard in the literature. This study aimed at evaluating the correlation between thyroid hormone levels and severity of liver disease.

MATERIALS AND METHODS

We measured thyroid hormone levels in 83 children with liver cirrhosis using radioimmunoassay techniques.

RESULTS

Four patients (4.8%) showed a decrease in the amount of T3 and 9 patients (10.8%) revealed increased levels of T3. Also, decreases were seen in the T4 levels of 7 patients (8.4%), and 4 patients (4.8%) showed increases in levels of T4. The serum albumin levels were lower and international normalized ratio was higher in patients with low T3 and low T4. This study reveals that the Model for End-Stage Liver Disease and Pediatric End-Stage Liver Disease scores are statistically related to the decreased amounts of T4 (P = .036). The Model for End-Stage Liver Disease and Pediatric End-Stage Liver Disease scores and the Child scores were higher in low T3 patients, but this was not significant (P > .05).

CONCLUSIONS

Decreased levels of thyroid hormones are correlated with the severity of disease and can be seen in more advanced cirrhosis. Patients with decreased T4 levels need a liver transplant more immediately than those patients that do not have decreased T4 levels.

Intestinal mucosal proliferation, apoptosis and oxidative stress in patients with liver cirrhosis

BACKGROUND

Intestinal mucosal barrier dysfunction in liver cirrhosis and its implicated mechanisms is of great clinical importance because it is associated with the development of serious complications from diverse organs through promotion of systemic endotoxemia.

AIM

The present study was designed to investigate whether enterocytes' proliferation, apoptosis and intestinal oxidative stress are altered in the intestinal mucosa of patients with compensated and decompensated liver cirrhosis.

MATERIAL AND METHODS

Twelve healthy controls (group A) and twenty four cirrhotic patients at a compensated (n = 12, group B) or decompensated condition (n = 12, group C) were subjected to duodenal biopsy. In intestinal specimens mucosal apoptotic and mitotic activity and their ratio were recorded by means of morphological assessment and mucosal lipid hydroperoxides were measured. Plasma endotoxin concentration, an index of gut barrier function, was also determined.

RESULTS

Cirrhotic patients presented significantly higher serum endotoxin concentrations as compared to healthy controls (P < 0.001), whilst endotoxemia was higher in decompensated disease (P < 0.05 vs. compensated cirrhosis). Intestinal mucosal mitotic count was significantly lower in patients with compensated and decompensated cirrhosis compared to controls (P < 0.01, respectively), whilst a trend towards increased apoptosis was recorded. The mitotic/apoptotic ratio was significantly reduced in groups B (P < 0.05) and C (P < 0.01) as compared to controls. Intestinal lipid peroxidation was significantly increased in decompensated cirrhotics (P < 0.001 vs. groups A and B).

CONCLUSIONS

The present study demonstrates for the first time that human liver cirrhosis is associated with decreased intestinal mucosal proliferation and proliferation/apoptosis ratio even at early stages of cirrhosis and increased intestinal oxidative stress in advanced liver disease.

Biological significance of a thyroid hormone-regulated secretome

The thyroid hormone, 3,3,5-triiodo-L-thyronine (T3), modulates several physiological processes, including cellular growth, differentiation, metabolism and proliferation, via interactions with thyroid hormone response elements (TREs) in the regulatory regions of target genes. Several intracellular and extracellular protein candidates are regulated by T3. Moreover, T3-regulated secreted proteins participate in physiological processes or cellular transformation. T3 has been employed as a marker in several disorders, such as cardiovascular disorder in chronic kidney disease, as well as diseases of the liver, immune system, endocrine hormone metabolism and coronary artery. Our group subsequently showed that T3 regulates several tumor-related secretory proteins, leading to cancer progression via alterations in extracellular matrix proteases and tumor-associated signaling pathways in hepatocellular carcinomas. Therefore, elucidation of T3/thyroid hormone receptor-regulated secretory proteins and their underlying mechanisms in cancers should facilitate the identification of novel therapeutic targets. This review provides a detailed summary on the known secretory proteins regulated by T3 and their physiological significance. This article is part of a Special Issue entitled: An Updated Secretome.

Prognostic value of malondialdehyde serum levels in severe sepsis: a multicenter study

Objective

The oxidant/antioxidant state in septic patients has only been studied in small series. We wished to determine whether malondialdehyde (MDA) serum levels were associated with severity and 30-day mortality in a large series of patients with sepsis.

Methods

We performed an observational, prospective, multicenter study in six Spanish Intensive Care Units. Serum levels of MDA were measured in a total of 228 patients (145 survivors and 83 non-survivors) with severe sepsis and 100 healthy controls.

Results

Serum levels of MDA were higher in severe septic patients than in healthy controls. Non-surviving septic patients had higher MDA values than survivors. MDA serum levels were associated with severity markers (lactic acid, SOFA, APACHE-II) and coagulation indices. Regression analysis showed that MDA serum levels were associated with 30-day survival (Hazard ratio = 1.05; 95% confidence interval = 1.009–1.091; p = 0.016). Receiver operating characteristic analysis showed that the area under curve of MDA serum levels to predict 30-day survival was 0.62 (95% CI = 0.56–0.69; P = 0.002). The risk of death in septic patients with MDA serum levels above 4.11 nmol/mL was higher than in patients with lower values (Hazard Ratio = 2.43; 95% CI = 1.49–3.94; p<0.001).

Conclusions

The novel findings of our study on severe septic patients, to our knowledge the largest series providing data on the oxidative state, are that elevated MDA serum levels probably represent an unbalanced oxidant state and are related with poor prognosis in patients with severe sepsis.

Ischemia-modified albumin in patients with hyperthyroidism and hypothyroidism

BACKGROUND

The relationship between ischemia-modified albumin (IMA) and thyroid dysfunction remains uncertain. This study aimed to investigate the influence of overt hypothyroidism (Oho), overt hyperthyroidism (Ohe), and their treatments on serum IMA levels.

METHODS

A total of 35 untreated patients with Ohe, 35 untreated patients with Oho, and 35 control subjects were enrolled in the study. C-reactive protein (CRP), homocysteine (Hcy), IMA, and lipid profiles were measured and evaluated before and after treatment.

RESULTS

CRP, Hcy, and IMA levels and lipid profiles were higher in patients with Oho than in euthyroid or Ohe subjects (p<0.05). Basal IMA levels were reduced after treatments in all patients (p<0.05). In Ohe patients, serum IMA levels were positively correlated with free triiodothyronine (r=0.424, p=0.011) and free thyroxine (r=0.567, p<0.001) levels. In Oho patients, serum IMA levels were inversely correlated with free triiodothyronine (r=-0.555, p=0.001) and free thyroxine (r=-0.457, p=0.006) but positively correlated with anti-thyroid peroxidase antibody, C-reactive protein, and homocysteine levels (p<0.05). Linear regression analyses showed that free triiodothyronine was the most important factor affecting serum IMA levels in Ohe (β=0.694, p=0.019) and in Oho (β=-0.512, p=0.025).

CONCLUSIONS

IMA levels are increased in patients with thyroid dysfunction, particularly in overt hypothyroidism. Thyroid dysfunction has a significant impact on the oxidative stress status.

Altered intestinal tight junctions' expression in patients with liver cirrhosis: a pathogenetic mechanism of intestinal hyperpermeability

BACKGROUND

Increased intestinal permeability in cirrhosis exerts a pivotal role in the pathogenesis of spontaneous bacterial peritonitis and other complications of cirrhosis through promotion of systemic endotoxemia. This study was designed to investigate whether the expression of tight junction (TJ) proteins, which regulate gut paracellular permeability, is altered in the intestinal mucosa of patients with liver cirrhosis and study its potential association with the stage of liver disease and the development of systemic endotoxemia.

DESIGN

Twenty-four patients with cirrhosis at a decompensated (n = 12, group A) or compensated condition (n = 12, group B) and 12 healthy controls (group C) were subjected to duodenal biopsy. The expression of the TJ proteins occludin and claudin-1 in the intestinal epithelium was evaluated by immunohistochemistry. Plasma endotoxin concentrations were also determined.

RESULTS

Patients with cirrhosis presented significantly higher serum endotoxin concentrations as compared to healthy controls (P < 0·001), whilst endotoxemia was higher in decompensated disease (P < 0·05 vs. compensated cirrhosis). Patients with decompensated and compensated cirrhosis presented significantly reduced expression of occludin and claudin-1 as compared to controls (P < 0·01, respectively). These alterations were significantly more pronounced in decompensated patients as compared to compensated (P < 0·05). Regarding occludin, in patients with cirrhosis, a specific pattern of expression in the intestinal epithelium was observed, with a gradually increasing loss of expression from crypt to tip of the villi. Occludin and claudin-1 expression were inversely correlated with Child-Pugh score (P < 0·001), the grade of oesophageal varices (P < 0·01) and endotoxin concentrations (P < 0·001).

CONCLUSIONS

This study demonstrates for the first time that human liver cirrhosis induces significant alterations in enterocytes' TJs. These changes might represent an important cellular mechanism for intestinal barrier dysfunction and hyperpermeability in patients with liver cirrhosis.

Normalization using a tagged-internal standard assay for analysis of antibody arrays and the evaluation of serological biomarkers for liver disease

For minimizing systemic experimental variation in the analysis of antibody array data, we developed a novel median-centered/IgM-tagged-internal standard (TIS) assay normalization using median-centering and TIS assay-based determination of serum IgM concentrations. We evaluated five normalization methods by analyzing correlation coefficients and coefficients of variation for six serum proteins using human serum samples from normal controls (n=25) and patients with liver cirrhosis (n=25) or hepatocellular carcinoma (HCC; n=29). Median-centered normalization improved correlation coefficients, while IgM-based normalizations improved coefficients of variation. The TIS assay was more efficient, economical, and reproducible for determining IgM concentrations than enzyme-linked immunosorbent assay. Additionally, we normalized antibody array data for six serum proteins using the median-centered/IgM-TIS assay, and evaluated serum biomarkers through distribution analysis of normalized fluorescence intensities and receiver operating characteristic analyses for the diagnosis of liver cirrhosis and HCC. Apolipoprotein A-1 and a combination of alpha-fetoprotein and C-reactive protein were determined to be potential serological biomarkers for liver cirrhosis and HCC, respectively. Thus, median-centered/IgM-TIS assay normalization is a useful approach for analyzing antibody array data and evaluating serological biomarkers for the diagnosis of liver disease or cancers.

Oxidative stress in chronic liver disease: relationship between peripheral and hepatic measurements

INTRODUCTION

Oxidative stress plays an important role in the pathogenesis of many liver diseases. Investigators often measure markers of oxidative stress in peripheral veins as a reflection of hepatic oxidative stress as it is not always feasible to measure oxidative stress in liver tissue. However, it is unknown whether markers of oxidative stress measured from peripheral sites accurately reflect hepatic tissue oxidative stress. The aim of this study is to examine the relationship of oxidative stress marker among hepatic tissue, hepatic and peripheral veins and urine.

METHODS

Malondialdehyde (MDA), a marker of oxidative stress was measured in hepatic vein, peripheral vein and urine samples from 26 consecutive patients undergoing transjugular liver procedures. In 19 patients undergoing liver biopsies, we measured MDA by immunohistochemical staining of paraffin-embedded liver tissue.

RESULTS

Peripheral venous MDA levels showed significant correlation with hepatic venous MDA levels (r = 0.62, P = 0.02), but they did not correlate with hepatic tissue MDA content (r = 0.22, P = 0.4). Hepatic venous MDA levels did not correlate with hepatic tissue MDA content (r = -0.01, P = 0.9). Subgroup analysis of patients without portal hypertension showed a positive correlation between hepatic venous and hepatic tissue MDA levels, but this was not statistically significant (r = 0.45, P = 0.22). Urinary MDA did not correlate with MDA from any other sampling location.

CONCLUSION

Oxidative stress measured from the peripheral venous samples is poorly reflective of hepatic tissue oxidative stress. Hepatic venous sampling might be suitable for assessing hepatic tissue oxidative stress in patients without portal hypertension, but a larger study is needed to examine this possibility.

Antioxidant defense and oxidative stress in children with acute hepatitis A

BACKGROUND AND OBJECTIVES

Published data on oxidative stress in children with acute hepatitis A are still very scarce. This study aims to evaluate the oxidant/antioxidant status of these patients.

DESIGN AND SETTING

Prospective, case-control study, over 2.5 years in patients under hospitalized and ambulatory care.

PATIENTS AND METHODS

The levels of a whole-blood antioxidant, reduced glutathione; and plasma antioxidants, β-carotene, retinol, ascorbic acid, α-tocopherol; and the biomarker of oxidative stress, malondialdehyde, were evaluated in 50 pediatric patients (age range, 5-16 years; 29 males and 21 females) with acute hepatitis A and in 50 healthy children as control subjects (age range, 5-16 years; 25 males and 25 females).

RESULTS

Plasma levels of reduced glutathione, β-carotene, retinol, α-tocopherol and ascorbic acid were significantly lower, while malondialdehyde plasma levels were significantly increased in the patient group when compared to the controls (P<.0001 for all parameters).

CONCLUSIONS

Our findings show that pediatric patients with acute hepatitis A were influenced by oxidative stress, resulting in significantly lower levels of plasma antioxidants and increased lipid peroxidation. In the absence of other therapeutic options, antioxidant vitamin supplements could be added to the therapy for these patients to help reestablish the oxidant status balance. Further investigations to confirm this suggestion are recommended.

Coinfection with hepatitis C virus, oxidative stress and antioxidant status in HIV-positive drug users in Miami

BACKGROUND

The pathogenesis of HIV/hepatitis C virus (HCV) coinfection is poorly understood. We examined markers of oxidative stress, plasma antioxidants and liver disease in HIV/HCV-coinfected and HIV-monoinfected adults.

METHODS

Demographics, medical history, and proof of infection with HIV, hepatitis A virus (HAV), hepatitis B virus (HBV) and HCV were obtained. HIV viral load, CD4 cell count, complete blood count (CBC), complete metabolic panel, lipid profile, and plasma concentrations of zinc, selenium, and vitamins A and E were determined. Malondialdehyde (MDA) and glutathione peroxidase concentrations were obtained as measures of oxidative stress. Aminotransferase to platelet ratio index (APRI) and fibrosis index (FIB-4) markers were calculated.

RESULTS

Significant differences were found between HIV/HCV-coinfected and HIV-monoinfected participants in levels of alanine aminotransferase (ALT) (mean±standard deviation: 51.4±50.6 vs. 31.9±43.1 U/L, respectively; P=0.014), aspartate aminotransferase (AST) (56.2±40.9 vs. 34.4±30.2 U/L; P<0.001), APRI (0.52±0.37 vs. 0.255±0.145; P=0.0001), FIB-4 (1.64±.0.91 vs. 1.03±0.11; P=0.0015) and plasma albumin (3.74±0.65 vs. 3.94±0.52 g/dL; P=0.038). There were no significant differences in CD4 cell count, HIV viral load or antiretroviral therapy (ART) between groups. Mean MDA was significantly higher (1.897±0.835 vs. 1.344± 0.223 nmol/mL, respectively; P=0.006) and plasma antioxidant concentrations were significantly lower [vitamin A, 39.5 ± 14.1 vs. 52.4±16.2 μg/dL, respectively (P=0.0004); vitamin E, 8.29±2.1 vs. 9.89±4.5 μg/mL (P=0.043); zinc, 0.61±0.14 vs. 0.67±0.15 mg/L (P=0.016)] in the HIV/HCV-coinfected participants than in the HIV-monoinfected participants, and these differences remained significant after adjusting for age, gender, CD4 cell count, HIV viral load, injecting drug use and race. There were no significant differences in glutathione peroxidase concentration, selenium concentration, body mass index (BMI), alcohol use or tobacco use between groups. Glutathione peroxidase concentration significantly increased as liver disease advanced, as measured by APRI (β=0.00118; P=0.0082) and FIB-4 (β=0.0029; P=0.0177). Vitamin A concentration significantly decreased (β=-0.00581; P=0.0417) as APRI increased.

CONCLUSION

HIV/HCV coinfection is associated with increased oxidative stress and decreased plasma antioxidant concentrations compared with HIV monoinfection. Research is needed to determine whether antioxidant supplementation delays liver disease in HIV/HCV coinfection.