Zinc and collagen content of cirrhotic liver

Zinc deficiency as an independent prognostic factor for patients with early hepatocellular carcinoma due to hepatitis virus

AIM

Although a reduced serum zinc level is often observed in patients with chronic liver disease due to hepatitis virus, its prognostic importance has not been adequately investigated. This study aimed to elucidate the association of zinc deficiency with prognosis, especially in early hepatocellular carcinoma (HCC) patients.

METHODS

From 2005 to 2018, 466 patients with naïve HCC due to hepatitis virus were enrolled (327 men, 139 women; median age 70 years; hepatitis C virus [HCV] n = 389, hepatitis B virus [HBV] n = 69, hepatitis C virus and hepatitis B virus n = 8; Child-Pugh A n = 367, Child-Pugh B n = 82; Child-Pugh C n = 17; TNM-LCSGJ stage I n = 150, stage II n = 181, stage III n = 91, stage IVa n = 26, state IVb n = 18). Of the 466 patients, 287 were within the Milan criteria (early HCC) and treated curatively. Zinc deficiency was defined as <60 μg/dL. Clinical records and prognostic factors were retrospectively evaluated.

RESULTS

The levels of serum zinc became lower with chronic liver disease progression (Child-Pugh A, B, C: 64.3 ± 14.3, 52.3 ± 15.7, 48.4 ± 13.5 μg/dL, respectively; P < 0.001). In early HCC patients treated curatively, overall survival and recurrence rates were better in patients treated curatively and without zinc deficiency as compared with patients with zinc deficiency (3-year overall survival 86.5% vs. 77.2%, 5-year overall survival 73.5% vs. 43.8%, P < 0.001; 3-year recurrence 44.8% vs. 58.3%, 5-year recurrence 56.8% vs. 77.5%, P = 0.002). Not only infection control of hepatitis virus (sustained virological response in HCV or nucleos(t)ide analogs in HBV; HR 0.078, P < 0.001), but also zinc deficiency (HR 1.773, P = 0.041) were significant prognostic factors for death.

CONCLUSION

Serum levels of zinc were reduced in association with chronic liver disease grade progression. In addition to infection control of hepatitis virus, zinc deficiency might be a significant prognostic factor for survival in patients with early HCC due to viral hepatitis treated curatively.

Hepatoprotection of Herpetospermum caudigerum Wall. against CCl4-induced liver fibrosis on rats

ETHNOPHARMACOLOGICAL RELEVANCE

Herpetospermum caudigerum Wall. (HCW) is a traditional Tibetan medicine, which has been used to ameliorate liver injuries in the folk.

AIM OF THE STUDY

Liver fibrosis has been recognized as a major lesion of the liver that leads to liver cirrhosis/hepatocarcinoma and even to death in the end. This study aims to demonstrate the protective effect of HCW against CCl₄-induced liver injury in rats and to explore the underlying mechanisms.

MATERIALS AND METHODS

Hepatic fibrosis was induced by intraperitoneal injection of CCl₄. Liver function markers, fibrosis markers, serum anti-oxidation enzymes as well as elements levels were determined. Serum and liver tissues were subjected to NMR-based metabolomics and multivariate statistical analysis.

RESULTS

HCW could significantly reduce the elevated levels of fibrosis markers such as hyaluronidase, laminin, Type III procollagen and Type IV collagen in the serum, improve the activities of the antioxidant enzymes, and effectively reverse the abnormal levels of elements in liver fibrosis rats. Correlation network analysis revealed that HCW could treat liver fibrosis by ameliorating oxidative stress, repairing the impaired energy metabolisms and reversing the disturbed amino acids and nucleic acids metabolisms.

CONCLUSION

This integrated metabolomics approach confirmed the validity of the traditional use of HCW in the treatment of liber fibrosis, providing new insights into the underlying mechanisms.

Tibetan Medical Formula Shi-Wei-Gan-Ning-Pill Protects Against Carbon Tetrachloride-Induced Liver Fibrosis - An NMR-Based Metabolic Profiling

Liver fibrosis is a severe health problem, threatening the life quality and causing death, raising great concerns worldwide. Shi-Wei-Gan-Ning-Pill (SWGNP) is a traditional Tibetan recipe used to treat hepatic injuries; however, its hepatoprotective mechanism has not yet fully clarified. In this study, histological staining, biochemical assays, and elements determination were applied to evaluate the anti-fibrotic efficacy of SWGNP on a carbon tetrachloride (CCl₄) induced hepato-fibrosis rat model. NMR-based metabolomics combined with orthogonal partial least squares-discriminant analysis (OPLS-DA), canonical regression analysis, and correlation networks analysis was used to characterize the potential biomarkers as well as metabolic pathways associated with the hepatoprotective activity of SWGNP. The results showed that SWGNP could significantly attenuate the pathological changes and decrease the levels of fibrosis markers (ColIV, HA, LN, and PCIII), and regulate the disordered elements distribution. Multivariate analysis and correlation network analysis revealed that SWGNP could protect rats against CCl₄-induced liver fibrosis through anti-oxidation, repairing the impaired energy metabolisms and reversing the disturbed amino acids and nucleic acids metabolisms. In conclusion, this integrated metabolomics approach provided new insights into the mechanism of the hepatoprotective effect of SWGNP in liver fibrosis disease.

Role of Zinc in the Development/Progression of Alcoholic Liver Disease

OPINION STATEMENT

Many variables, aside from the amount and duration of alcohol consumption, play a role in the development and progression of alcoholic liver disease (ALD). One critical factor that can be modified is diet/nutrition. We have made major recent advances in our understanding of the interactions of nutrition and ALD. In this article, we review advances made in zinc metabolism/therapy for ALD. There is major zinc dyshomeostasis with ALD which is mediated, in part, by poor intake and absorption, increased excretion, and altered zinc transporters, especially ZIP14. Zinc deficiency plays an etiologic role in multiple mechanisms of ALD, ranging from intestinal barrier dysfunction to hepatocyte apoptosis. Zinc supplementation is highly effective at correcting these ALD mechanisms and preventing/treating experimental ALD. There is no Food and Drug Administration (FDA) approved therapy for any stage of ALD. Because animal and human data suggest that zinc deficiency occurs early in the course of ALD, we treat most ALD patients with daily oral zinc supplementation (220 mg zinc sulfate which contains 50 mg elemental zinc).

Application of UVA-riboflavin crosslinking to enhance the mechanical properties of extracellular matrix derived hydrogels

Hydrogels derived from extracellular matrix (ECM) have become increasing popular in recent years, particularly for use in tissue engineering. One limitation with ECM hydrogels is that they tend to have poor mechanical properties compared to native tissues they are trying to replicate. To address this problem, a UVA (ultraviolet-A) riboflavin crosslinking technique was applied to ECM hydrogels to determine if it could be used to improve their elastic modulus. Hydrogels fabricated from corneal, cardiac and liver ECM were used in this study. The mechanical properties of the hydrogels were characterized using a spherical indentation technique. The microstructure of the hydrogels and the cytotoxic effect of crosslinking on cell seeded hydrogels were also evaluated. The combination of UVA light and riboflavin solution led to a significant increase in elastic modulus from 6.8kPa to 24.7kPa, 1.4kPa to 6.9kPa and 0.9kPa to 1.6kPa for corneal, cardiac and liver ECM hydrogels respectively. The extent of this increase was dependent on a number of factors including the UVA exposure time and the initial hydrogel concentration. There were also a high percentage of viable cells within the cell seeded hydrogels with 94% of cells remaining viable after 90min exposure to UVA light. These results suggest that UVA-riboflavin crosslinking is an effective approach for improving the mechanical properties of ECM hydrogels without resulting in a significant reduction of cell viability.

Can zinc enhance response interferon therapy for patients with HCV-related liver disease?

Patients with liver disease may be at risk of zinc depletion. Zinc supplementation has been shown to contribute to inhibition of liver fibrosis and improvement in hepatic encephalopathy. However, little is known about the anti-inflammatory effect of zinc on hepatitis C virus (HCV)-related chronic liver disease. The standard of care for chronic HCV has improved markedly since the approval of interferon (IFN) therapy more than a decade ago. Over the past 20 years, IFN therapy has improved to more effectively eliminate the virus, progressing from single IFN therapy to combination therapy with ribavirin (RBV) and finally to pegylated IFN (PEG-IFN) therapy. However, even combined therapy with PEG-IFN and RBV for 48 wk is unable to eliminate the virus in some 40% of hepatitis C cases, particularly those with genotype 1b and high viral load. Treatment options for patients who have relapsed or are refractory to treatment with PEG-IFN and RBV therefore need to be critically assessed. This paper overviews the relationship between chronic liver disease and zinc metabolism.

Zinc supplementation improves the outcome of chronic hepatitis C and liver cirrhosis

We treated patients with C-viral chronic hepatitis (CH) and liver cirrhosis (LC) with polaprezinc and determined prospectively the effect on long-term outcome. 62 patients were enrolled. Of these, 32 were administered 1.0 g polaprezinc and the remainder were not administered polaprezinc. We measured the serum zinc concentrations using conventional atomic absorption spectrometry and conducted a prospective study to determine the long-term outcome of the polaprezinc therapy. Changes of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels in the polaprezinc administration group were significantly lower than those of the untreated group. The decrease in platelet count was clearly less than that of the untreated group. The factors that inhibited increases in serum zinc concentrations following administration of polaprezinc included low serum zinc concentration states. Furthermore, the reductions of AST and ALT levels in the low zinc group were significantly greater than those of the high zinc group. When the patients who were administered polaprezinc were divided into two groups whose zinc concentrations increased (zinc responders) or remained stable or decreased (zinc non-responders), the zinc responders had a clearly lower cumulative incidence of HCC than the zinc non-responders. We conclude zinc supplementation improved the long-term outcome in C-viral CH and LC patients.

Zinc supplementation improves the outcome of chronic hepatitis C and liver cirrhosis

We treated patients with C-viral chronic hepatitis (CH) and liver cirrhosis (LC) with polaprezinc and determined prospectively the effect on long-term outcome. 62 patients were enrolled. Of these, 32 were administered 1.0 g polaprezinc and the remainder were not administered polaprezinc. We measured the serum zinc concentrations using conventional atomic absorption spectrometry and conducted a prospective study to determine the long-term outcome of the polaprezinc therapy. Changes of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels in the polaprezinc administration group were significantly lower than those of the untreated group. The decrease in platelet count was clearly less than that of the untreated group. The factors that inhibited increases in serum zinc concentrations following administration of polaprezinc included low serum zinc concentration states. Furthermore, the reductions of AST and ALT levels in the low zinc group were significantly greater than those of the high zinc group. When the patients who were administered polaprezinc were divided into two groups whose zinc concentrations increased (zinc responders) or remained stable or decreased (zinc non-responders), the zinc responders had a clearly lower cumulative incidence of HCC than the zinc non-responders. We conclude zinc supplementation improved the long-term outcome in C-viral CH and LC patients.

Clinical significance of evaluation of serum zinc concentrations in C-viral chronic liver disease

We evaluated zinc concentrations in patients with hepatitis C virus (HCV)-positive chronic liver disease and correlated them with the clinical profiles of the patients. A total of 100 patients with chronic hepatitis (CH), 29 with liver cirrhosis (LC), and 6 who were asymptomatic HCV carriers (ASC) were examined. All of the patients were positive for serum HCV RNA. One hundred eighteen HCV antibody-positive hepatocellear carcinoma (HCC) patients and 11 healthy subjects also were included in this study. Serum zinc concentrations were evaluated using conventional atomic absorption spectrometry. The median concentration of zinc in patients with CH was statistically lower than that in healthy control subjects. The median zinc concentrations of the LC and HCC groups were significantly lower than that of the CH group. A significant correlation was observed between the zinc concentrations and the platelet counts and albumin concentrations. The zinc concentrations did not correlate with tumor size and number and decreased with the development of Child-Pugh stage. The cumulative survival rate after therapy for HCC nodules in the low zinc concentration group was significantly lower than in the high group. We conclude that the serum concentration of zinc influences the clinical profiles in patients with C-viral chronic liver disease.

Metallothionein synthesis induced by interferon alpha/beta in mice of various zinc status

We studied the ability of interferon alpha/beta (IFN) to induce metallothionein (MT) synthesis in mice. Male mice were injected intraperitoneally with mouse IFN (5 x 10(5) IU/mouse). Plasma Zn levels were reduced at 4 hr after injection, reached a minimum value at 6 hr, and then returned to the control level at 8 hr. Hepatic MT concentrations began to increase at 4 hr and reached maximum values at 6 hr. Induction of MT gene expression and protein synthesis was confirmed by Northern blot analysis and radioimmunoassay, respectively. The induction of MT synthesis in the liver by IFN was dose-dependent. The data suggest that induction of MT-mRNA and the protein in the liver by IFN occurs rapidly but is rather transient. Furthermore, MT synthesis was not induced by IFN in the liver of mice given a Zn-deficient diet, whereas IFN induced increases in the activity of 2',5'-oligoadenylate synthetase in the spleen were unaffected by Zn status. Thus, induction of hepatic MT synthesis by IFN is influenced by Zn status.

Zinc, iron, and peroxidation in liver tissue. Cumulative effects of alcohol consumption and virus-mediated damage--a preliminary report

In an attempt to elucidate further the mechanisms involved in alcohol-mediated liver damage and the correlation between alcohol and viruses in chronic liver lesions, we determined the levels of liver glutathione (GSH), thiobarbituric acid reactive substances (TBARS), iron (Fe), and zinc (Zn) in 31 patients with chronic viral hepatitis (CAH), 6 with alcohol-related chronic hepatitis (CALD), 6 with alcoholic cirrhosis (AC), 8 with primary biliary cirrhosis (PBC), and 10 healthy controls (C). Liver GSH was significantly lower in CALD and AC patients (p < 0.005). TBARS levels were significantly higher in CAH, CALD, and PBC patients (p < 0.001, < 0.02, and < 0.001, respectively). In CAH patients, alcohol consumption correlated inversely with GSH and directly with TBARS (p < 0.05). Patients with both CAH and alcohol abuse had a further reduction in liver GSH levels (p < 0.005). Tissue levels of Fe were significantly increased in CALD and AC patients with respect to controls and CAH patients, whereas no significant difference was observed in Zn. These data confirm that patients with chronic ethanol exposure reveal a depletion in liver GSH content clearly correlated with an increase in lipid peroxidation and Fe liver storage. On the other hand, these findings appear to suggest no significant change in Zn levels in chronic hepatitis.

Effect of ethanol on hepatic iron, copper, zinc and manganese contents in the male albino mouse

Liver Fe and Cu contents (determined by atomic absorption spectrophotometry) were found to be higher in alcoholized male albino mice than in controls. Alcoholized animals killed at the 180th day of life also showed higher liver Fe and Cu contents than the alcoholized animals sacrificed at the 85th day of life. A significant correlation was established between liver Fe content and size of the pericentral hepatocytes and their nuclei. No differences between alcoholic and controls were obtained regarding liver Zn content, whereas Mn showed a clear tendency to be higher in the alcoholics.

Hepatic zinc content in patients with various stages of alcoholic liver disease and in patients with chronic active and chronic persistent hepatitis

The hepatic zinc content was determined in liver biopsies of patients with alcoholic and nonalcoholic liver disease using proton-induced X-ray emission. The values obtained in postmortem specimens of the liver from 27 patients with no evidence of acute or chronic liver disease served as controls. The mean value and the range of the zinc content in the controls (75 +/- 24 ppm wet weight) are in good agreement with those reported in the literature. The hepatic zinc content in the control group showed no significant age or sex dependence. The mean zinc content was significantly decreased in all groups of patients with alcoholic liver disease. The decrease was comparable in biopsies from patients with alcoholic fatty liver (-56.7%, n = 12), mild alcoholic hepatitis (-50.5%, n = 6) and alcoholic cirrhosis (-45.6%, n = 10). The hepatic zinc content was also distinctly reduced in patients with chronic active hepatitis (-60.3%, n = 15) and in those with chronic persistent hepatitis (-44.9%, n = 8). The estimation of the zinc content in subcellular fractions of the liver performed in postmortem specimens from seven patients with alcoholic liver cirrhosis and in six controls revealed a significant reduction in the zinc content in the fraction containing cell nuclei and membranes and in the mitochondrial fraction. A similar decrease was seen in the 100,000 g supernatant; however, the difference did not attain statistical difference. The zinc content of the microsomal fraction in the controls was lower than in the other three cell fractions.(ABSTRACT TRUNCATED AT 250 WORDS)

Zinc plasma levels after oral zinc tolerance test in nonalcoholic cirrhosis

Zinc absorption was examined in 25 nonalcoholic cirrhotic patients using the oral zinc tolerance test and comparing results to a healthy control group. With 22.5 mg elementary zinc, the increase in plasma zinc was significantly lower in the cirrhotic patients than in the control group with P less than 0.01 in the first and second hours and P less than 0.05 in the fourth hour. The zinc malabsorption may result from an abnormal small intestinal mucosa. Indeed small intestinal biopsies in all patients showed partial shortening and prominent distension of villi and intense stromal edema with inflammatory cell infiltration of the lamina propria. However, it is not clear whether these intestinal changes are due to zinc deficiency or to portal hypertension. Thus zinc malabsorption appears to contribute to zinc deficiency in nonalcoholic cirrhotics and seems to result, in part, from pathological changes in the mucosa.

Trace elements in normal and cirrhotic human liver tissue. I. Iron, copper, zinc, selenium, manganese, titanium and lead measured by X-ray fluorescence spectrometry

Trace elements (Fe, Cu, Zn, Se, Mn, Ti, Pb) were measured by X-ray fluorescence spectrometry in normal liver tissue obtained at autopsy from 74 subjects (44 male, 30 female), median age 62 years (range 20-87), and in tissue from 27 cirrhotic livers (14 alcoholic, 13 non-alcoholic cirrhosis). The element content (median and 5-95 percentile interval) in normal livers in mmol/kg dry tissue was: Fe, 16.51 (7.82-39.03); Cu, 0.378 (0.189-0.629); Zn, 4.01 (2.59-9.33); Se, 0.018 (less than 0.004-0.035); Mn, less than 0.055 (less than 0.055-0.237); Ti, less than 0.146 (less than 0.146-0.919); Pb, less than 0.0005 (less than 0.0005-0.0154). Only copper content showed a sex difference, being higher in males than in females (P less than 0.04). In both groups of cirrhotic liver, Fe content was within normal, Cu content above normal (P less than 0.05, P less than 0.02), and Se content below normal (P less than 0.0001, P less than 0.04). Alcoholic cirrhotic livers had lower Zn levels (P less than 0.02), higher Mn levels (P less than 0.06), and higher Pb levels (P less than 0.03) than normal livers.

Protective effect of zinc against ethanol toxicity in mice

Protection against the lethal effects of ethanol at 4.5 g/kg administered acutely was maximal when zinc was administered 60 min prior to ethanol. The timing of ethanol administration corresponded with elevated plasma levels of absorbed zinc. Protection was inversely related to the dose of zinc employed, as 0.5 mumol provided greater protection than 1.0 mumol, which provided greater protection than 2.0 mumol. Protection against ethanol lethality was greater if zinc was administered 60 min prior to each injection of ethanol. Acute zinc pretreatment did not alter the activity of liver alcohol dehydrogenase (ADH), nor did it alter the blood clearance of ethanol. Chronic zinc administration as ZnCl2, 100 micrograms/ml in the drinking water for 30 d, produced a 25% decrease in hepatic ADH activity, which was accompanied by a similar decrease in the intravascular clearance of ethanol.

Trace elements in human body fluids and tissues

Published figures for trace element concentrations in body fluids and tissues of apparently healthy subjects are widely divergent. For a considerable time, the apparent disparities were readily ascribed to biological sources of variation such as age, sex, dietary habits, physiological conditions, environmental exposure, geographical circumstances, or similar influences. Growing evidence, however, suggests that this interpretation may be seriously questioned in numerous instances. First, values obtained in reference materials leave no doubt that some previous studies must have been subject to gross analytical inaccuracies. Second, it has now been thoroughly documented that inadequate sample collection and manipulation may drastically distort the intrinsic trace element content of biological matrices. This review scrutinizes data reported by a number of investigators. In an effort to settle the currently flourishing confusion, critically selected reference values are set forth for trace element levels in human blood plasma or serum, packed blood cells, urine, lung, liver, kidney, and skeletal muscle tissue.

Zinc absorption in patients with compensated alcoholic cirrhosis

Zinc absorption was measured by whole-body counting in 10 patients with compensated alcoholic cirrhosis without steatorrhoea and in 8 healthy subjects. After oral administration of 65Zn the absorption was measured at regular intervals until a straight time/activity retention curve was obtained in a semilogarithmic system, whereafter it was calculated by extrapolation to time zero. Cirrhotic patients had a median absorption of 69% (27-90%), compared with 42% (25-67%) in healthy subjects (P less than 0.01). Median T1/2 of 65Zn as calculated from the retention curve was 156 days (83-280 days) in cirrhotic patients and 103 days (72-132 days) in healthy subjects (P less than 0.05). Median serum zinc value was 11 mumol/l (9-17 mumol/l) in cirrhotic patients and 16 mumol/l (12-17 mumol/l) in healthy subjects (P less than 0.01). Median erythrocyte zinc value was 224 mumol/l (205-281 mumol/l) in cirrhotics and 223 mumol/l (188-275 mumol/l) in healthy subjects (P less than 0.1). Six cirrhotic patients, of whom four took diuretics, had increased urinary zinc excretion (greater than 15 mumol/24 h). Zinc absorption seems intact in compensated alcoholic cirrhosis. The increased absorption and prolonged T1/2 of 65Zn might be compensatory to a moderate zinc depletion.

Rapid loss of delta-aminolevulinic acid dehydratase activity in primary cultures of adult rat hepatocytes: a new model of zinc deficiency

Nonproliferating cultures of adult rat hepatocytes were found to lose 60-70% of cell-associated zinc during their first 24 h of incubation in standard, serum-free medium. The loss of zinc was accompanied by a profound loss (greater than 95%) in the activity of the zinc metalloenzyme, delta-aminolevulinic acid dehydratase, as well as a loss (greater than 85%) in the cellular content of immunoreactive delta-aminolevulinic acid dehydratase protein. Restoration of cellular zinc content by the addition of zinc to the culture medium partially prevented the losses of both delta-aminolevulinic acid dehydratase activity and immunoreactive protein. Since the spontaneous, selective loss of cellular zinc appears to have specific effects on a relevant hepatic function, this culture system constitutes a novel in vitro model of zinc deficiency in mature liver.

Effects of divalent cations on collagen biosynthesis in isolated chick embryo tendon cells

Isolated chick embryo tendon cells were used in [14C]proline and [14C]lysine labelling experiments to investigate the effect of divalent cations on collagen biosynthesis with a special reference to prolyl hydroxylation and lysyl modifications. The following metals were studied by adding them to the incubation medium of the cells: Ca2+, Cd2+, Co2+, Hg2+, Mg2+, Mn2+, Ni2+, Pb2+ and Zn2+. Zn2+ caused a potent reductin in collagen prolyl hydroxylation with a concomitant increased cellular retention of collagenase-digestible material. These effects were detectable even at physiological concentrations. At the same concentrations of Zn2+, lysyl hydroxylation was considerably less inhibited than prolyl hydroxylation, and the extent of hydroxylysyl glycosylation was even increased. Co2+ was also an efficient inhibitor of collagen prolyl hydroxylation, but at concentrations ten times higher than those of Zn2+. In the presence of other metal ions, no or only up to 10% inhibition of prolyl hydroxylation was noted even at those concentrations at which [14C]proline incorporation into the protein was decreased. However, an increased cellular retention of collagen was detected in the presence of some metal ions. No reduction in lysyl hydroxylation was found in the presence of Ca2+ or Mg2+.

Reduced leucocyte zinc in liver disease

The zinc content of peripheral blood leucocytes has been measured in normal controls and in three groups of patients with liver disease. A significant reduction in leucocyte zinc, but not erythrocyte zinc, was observed in patients with primary biliary cirrhosis, alcoholic cirrhosis, and active chronic hepatitis. It is suggested that the nucleated tissues of some patients with liver disease are therefore zinc deficient, and that leucocyte zinc may prove of value in the assessment of the zinc status of such patients.

Zinc depletion in alcoholic liver diseases

Liver and serum zinc concentrations were investigated in 24 patients with alcoholic liver diseases, 22 patients with non-alcoholic liver diseases, and in 36 control subjects. The liver samples were obtained by percutaneous liver biopsies, and the ratio of hepatocytes to fibrous connective tissue was estimated. The liver zinc concentration was expressed in relation to the amount of hepatocytes, and the serum zinc concentration was calculated in relation to total, albumin-, and alpha 2-macroglobulin-bound serum zinc. The results show that the liver zinc concentration was decreased in patients with alcoholic liver diseases (P < 0.01), in contrast to in patients with non-alcoholic liver diseases. Albumin-bound serum zinc was decreased in both groups (P < 0.001). The results indicate that alcoholic liver damage is associated with zinc deficiency.

Distribution of serum zinc between albumin and alpha2-macroglobulin in patients with decompensated hepatic cirrhosis

Lower concentrations of total serum zinc (540 +/- 111 mug/1, mean +/- SEM), and of albumin-bound serum zinc (295 +/- 113 mug/1) and a higher concentration of alpha2-macroglobulin-bound zinc (245 +/- 69 mug/1) were found in 25 patients with decompensated hepatic cirrhosis, compared to 28 healthy subjects (835 +/- 91; 679 +/- 83; 156 +/- 27 mug/1 respectively). Levels of total and albumin-bound zinc were significantly and positively correlated with serum albumin levels. Higher levels of alpha2-macroglobulin-bound zinc were associated with higher levels of alpha2-macroglobulin in these patients (2.8 +/- 0.8 g/1) compared to normals (2.3 +/- 0.6). Hence, not only do decompensated cirrhotics exhibit a lower serum zinc level but a greater proportion of this zinc is associated with the tightly bound, and presumably metabolically more inert, serum fraction. This situation exaggerates the zinc deficiency state of the severe cirrhotic.

Urinary zinc in hepatic cirrhosis

Plasma Zinc and renal clearance of Zinc have been studied in patients with various chronic hepatic disorders. Plasma Zinc levels were reduced in patients with all forms of chronic hepatic disease and were of no value in differentiating these conditions. The renal clearance of Zinc was found to be significantly higher in patients with chronic hepatic disease of alcoholic aetiology (1.25 ml./min.) compared with those of non-alcoholic aetiology (0.52 ml./min.) and normal subjects (0.33 ml./min.). The renal clearance of Zinc may be of value in identifying chronic hepatic disease in which alcohol is aetiologically involved.

Plasma and urinary zinc in patients with malabsorption syndromes or hepatic cirrhosis

Plasma and urinary zinc have been measured in 19 patients with malabsorption and 21 patients with hepatic cirrhosis. The results have been compared with those of 20 control subjects and 23 patients with a variety of other diseases. The diurnal variation in plasma zinc levels has been confirmed and is of such magnitude that this must be taken into account in comparing results in groups of subjects. Plasma zinc levels, both fasting and after a meal, are significantly lower in patients with cirrhosis (71 and 60 mug/100 ml) and malabsorption (76 and 64 mug/100 ml) than in controls (97 and 81 mug/100 ml). In the patients with cirrhosis or malabsorption similar correlations exist between plasma zinc and plasma albumin, suggesting that the low plasma zinc levels may be, at least in part, dependent on the plasma albumin level. Urinary zinc excretion is increased in cirrhosis, but not in malabsorption, indicating that increased urinary loss is unlikely to explain the low plasma levels.