Also See
Alcohol Consumption – Estrogen and Progesterone In Women
How does estrogen enhance endotoxin toxicity? Let me count the ways.
PUFA and Liver Toxicity; Protection by Saturated Fats
Endotoxin: Poisoning from the Inside Out
Estrogen and Liver Toxicity
Single Bout of Binge Drinking Linked to Immune System Effects
Estrogen makes the toxic-mediator-producing cells in the liver (Kupffer cells) hypersensitive to LPS–15 times more sensitive than normal (Ikejima, et al., 1998). One way estrogen increases the toxicity of endotoxin is probably by making the intestine more permeable (Enomoto, et al., 1999). -Ray Peat, PhD
AJP – GI April 1, 1998 vol. 274 no. 4 G669-G676
Estrogen increases sensitivity of hepatic Kupffer cells to endotoxin
Kenichi Ikejima1,2, Nobuyuki Enomoto1, Yuji Iimuro1, Ayako Ikejima2, Dawn Fang1, Juliana Xu1, Donald T. Forman3, David A. Brenner2, and Ronald G. Thurman1
The relationship among gender, lipopolysaccharide (LPS), and liver disease is complex. Accordingly, the effect of estrogen on activation of Kupffer cells by endotoxin was studied. All rats given estrogen intraperitoneally 24 h before an injection of a sublethal dose of LPS (5 mg/kg) died within 24 h, whereas none of the control rats died. Mortality was prevented totally by pretreatment with gadolinium chloride, a Kupffer cell toxicant. Peak serum tumor necrosis factor-α (TNF-α) values as well as TNF-α mRNA in the liver after LPS were twice as high in the estrogen-treated group as in the untreated controls. Plasma nitrite levels and inducible nitric oxide synthase in the liver were also elevated significantly in estrogen-treated rats 6 h after LPS. Furthermore, Kupffer cells isolated from estrogen-treated rats produced about twice as much TNF-α and nitrite as controls did in response to LPS. In addition, Kupffer cells from estrogen-treated rats required 15-fold lower amounts of LPS to increase intracellular Ca2+ than controls did, and Kupffer cells from estrogen-treated animals expressed more CD14, the receptor for LPS/LPS binding protein, than controls. Moreover, estrogen treatment increased LPS binding protein mRNA dramatically in liver in 6–24 h. It is concluded that estrogen treatment in vivo sensitizes Kupffer cells to LPS, leading to increased toxic mediator production by the liver.
Am J Physiol. 1999 Sep;277(3 Pt 1):G671-7.
Estriol sensitizes rat Kupffer cells via gut-derived endotoxin.
Enomoto N, Yamashina S, Schemmer P, Rivera CA, Bradford BU, Enomoto A, Brenner DA, Thurman RG.
The relationship between gender and alcohol-induced liver disease is complex; however, endotoxin is most likely involved. Recently, it was reported that estriol activated Kupffer cells by upregulation of the endotoxin receptor CD14. Therefore, the purpose of this work was to study how estriol sensitizes Kupffer cells. Rats were given estriol (20 mg/kg ip), and Kupffer cells were isolated 24 h later. After addition of lipopolysaccharide (LPS), intracellular Ca2+ concentration was measured using a microspectrofluorometer with the fluorescent indicator fura 2, and tumor necrosis factor-alpha was measured by ELISA. CD14 was evaluated by Western analysis. One-half of the rats given estriol intraperitoneally 24 h before an injection of a sublethal dose of LPS (5 mg/kg) died within 24 h, whereas none of the control rats died. Mortality was prevented totally by sterilization of the gut with antibiotics. A similar pattern was obtained with liver histology and serum transaminases. Translocation of horseradish peroxidase was increased about threefold in gut segments by treatment with estriol. This increase was not altered by treatment with nonabsorbable antibiotics. On the other hand, endotoxin levels were increased to 60-70 pg/ml in plasma of rats treated with estriol. As expected, this increase was prevented (<20 pg/ml) by antibiotics. In isolated Kupffer cells, LPS-induced increases in intracellular Ca2+ concentration, tumor necrosis factor-alpha production, and CD14 were increased, as previously reported. All these phenomena were blocked by antibiotics. Therefore, it is concluded that estriol treatment in vivo sensitizes Kupffer cells to LPS via mechanisms dependent on increases in CD14. This is most likely due to elevated portal blood endotoxin caused by increased gut permeability.
Hepatology. 2000 Jan;31(1):117-23.
Estrogen is involved in early alcohol-induced liver injury in a rat enteral feeding model.
Yin M, Ikejima K, Wheeler MD, Bradford BU, Seabra V, Forman DT, Sato N, Thurman
The aim of this study was to investigate whether reduction in blood estrogen by removal of the ovaries would decrease the sensitivity of female rats to early alcohol-induced liver injury using an enteral ethanol feeding model, and if so, whether estrogen replacement would compensate. Livers from ovariectomized rats with or without estrogen replacement after 4 weeks of continuous ethanol exposure were compared with nonovariectomized rats in the presence or absence of ethanol. Ethanol increased serum alanine transaminase (ALT) levels from 30 +/- 6 to 64 +/- 7 U/L. This effect was blocked by ovariectomy (31 +/- 7) and totally reversed by estrogen replacement (110 +/- 23). Ethanol increased liver weight and fat accumulation, an effect that was minimized by ovariectomy and reversed partially by estrogen replacement. Infiltrating leukocytes were increased 6. 7-fold by ethanol, an effect that was blunted significantly by ovariectomy and reversed by estrogen replacement. Likewise, a similar pattern of changes was observed in the number of necrotic hepatocytes. Blood endotoxin and hepatic levels of CD14 messenger RNA (mRNA) and protein were increased by ethanol. This effect was blocked in ovariectomized rats and elevated by estrogen replacement. Moreover, Kupffer cells isolated from ethanol-treated rats with estrogen replacement produced more tumor necrosis factor alpha (TNF-alpha) than those from control and ovariectomized rats. It is concluded, therefore, that the sensitivity of rat liver to alcohol-induced injury is directly related to estrogen, which increases endotoxin in the blood and CD14 expression in the liver, leading to increased TNF-alpha production.
Am J Physiol Gastrointest Liver Physiol. 2000 Apr;278(4):G652-61.
Gender differences in early alcohol-induced liver injury: role of CD14, NF-kappaB, and TNF-alpha.
Kono H, Wheeler MD, Rusyn I, Lin M, Seabra V, Rivera CA, Bradford BU, Forman DT, Thurman RG.
The purpose of this study was to determine whether early alcohol-induced liver injury (ALI) in females is associated with changes in CD14 on Kupffer cells, activation of hepatic nuclear factor (NF)-kappaB, and expression of tumor necrosis factor (TNF)-alpha mRNA. Male and female rats were given high-fat control or ethanol-containing diets for 4 wk using the intragastric enteral protocol. Physiological parameters were similar in both genders. Ethanol was increased as tolerance developed with higher blood levels than previously observed, resulting in a fourfold increase in aspartate aminotransferase (males 389 +/- 47 IU/l vs. females 727 +/- 66 IU/l). Hepatic pathology developed more rapidly and was nearly twofold greater and endotoxin levels were significantly higher in females after ethanol. Also, expression of CD14 on Kupffer cells was 1.5-fold greater and binding of transcription factor NF-kappaB in hepatic nuclear extracts and TNF-alpha mRNA expression were threefold greater in females. These data are consistent with the hypothesis that elevated endotoxin after ethanol triggers more activation of Kupffer cells via enhanced CD14 expression in females. NF-kappaB is activated in this process, leading to increases in TNF-alpha mRNA expression in the liver and more severe liver injury in females. It is concluded that gender differences in ALI are dependent on endotoxin and a signaling cascade leading to TNF-alpha.
World J Gastroenterol. 2010 Mar 21;16(11):1377-84.
Alcoholic liver injury: influence of gender and hormones.
Eagon PK.
This article discusses several subjects pertinent to a consideration of the role of gender and hormones in alcoholic liver injury (ALI). Beginning with an overview of factors involved in the pathogenesis of ALI, we review changes in sex hormone metabolism resulting from alcohol ingestion, summarize research that points to estrogen as a cofactor in ALI, consider evidence that gut injury is linked to liver injury in the setting of alcohol, and briefly review the limited evidence regarding sex hormones and gut barrier function. In both women and female animals, most studies reveal a propensity toward greater alcohol-induced liver injury due to female gender, although exact hormonal influences are not yet understood. Thus, women and their physicians should be alert to the dangers of excess alcohol consumption and the increased potential for liver injury in females.
Am J Physiol Gastrointest Liver Physiol. 2001 Dec;281(6):G1348-56.
Increased severity of alcoholic liver injury in female rats: role of oxidative stress, endotoxin, and chemokines.
Nanji AA, Jokelainen K, Fotouhinia M, Rahemtulla A, Thomas P, Tipoe GL, Su GL, Dannenberg AJ.
Alcoholic liver injury is more severe and rapidly developing in women than men. To evaluate the reason(s) for these gender-related differences, we determined whether pathogenic mechanisms important in alcoholic liver injury in male rats were further upregulated in female rats. Male and age-matched female rats (7/group) were fed ethanol and a diet containing fish oil for 4 wk by intragastric infusion. Dextrose isocalorically replaced ethanol in control rats. We analyzed liver histopathology, lipid peroxidation, cytochrome P-450 (CYP)2E1 activity, nonheme iron, endotoxin, nuclear factor-kappa B (NF-kappa B) activation, and mRNA levels of cyclooxygenase-1 (COX-1) and COX-2, tumor necrosis factor-alpha (TNF-alpha), monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-2 (MIP-2). Alcohol-induced liver injury was more severe in female vs. male rats. Female rats had higher endotoxin, lipid peroxidation, and nonheme iron levels and increased NF-kappa B activation and upregulation of the chemokines MCP-1 and MIP-2. CYP2E1 activity and TNF-alpha and COX-2 levels were similar in male and female rats. Remarkably, female rats fed fish oil and dextrose also showed necrosis and inflammation. Our findings in ethanol-fed rats suggest that increased endotoxemia and lipid peroxidation in females stimulate NF-kappa B activation and chemokine production, enhancing liver injury. TNF-alpha and COX-2 upregulation are probably important in causing liver injury but do not explain gender-related differences.
J Hepatol. 2001 Jul;35(1):46-52.
The antiestrogen toremifene protects against alcoholic liver injury in female rats.
Järveläinen HA, Lukkari TA, Heinaro S, Sippel H, Lindros KO.
BACKGROUND/AIMS:
Females are generally considered to be more susceptible to alcohol-induced liver injury than males. To elucidate whether gonadal hormones are involved, female rats were chronically treated with ethanol and with an antiestrogen.
METHODS:
Ethanol was administered in a low-carbohydrate liquid diet. Estrogen action was blocked by daily intubation of toremifene, a non-hepatotoxic second generation estrogen receptor antagonist.
RESULTS:
The female rats consuming intoxicating amounts of ethanol diet for 6 weeks developed massive microvesicular/macrovesicular steatosis, frequent inflammatory foci and spotty necrosis. Serum alanine aminotransferase increased 7-fold. Toremifene treatment did not affect steatosis, but significantly reduced inflammation and necrosis. Ethanol increased the expression of CD14 and tumor necrosis factor- (TNF) alpha mRNA and also the production of TNF-alpha by isolated Kupffer cells, but toremifene had no significant counteracting effect. However, toremifene significantly alleviated both ethanol induction of the pro-oxidant enzyme CYP2E1 and ethanol reduction of the oxidant-protective enzyme Se-glutathione peroxidase.
CONCLUSIONS:
The partial protection by toremifene against ethanol-induced liver lesions suggests a pathogenic contribution of estrogens, possibly associated with an oxygen radical mediated mechanism.
Am J Physiol. 1997 May;272(5 Pt 1):G1186-94.
Female rats exhibit greater susceptibility to early alcohol-induced liver injury than males.
Iimuro Y, Frankenberg MV, Arteel GE, Bradford BU, Wall CA, Thurman RG.
It is known that women develop hepatic injury more rapidly and with exposure to less ethanol than men; however, mechanisms remain unclear. The purpose of this study was to determine if an enteral alcohol delivery model could be used to study susceptibility of females to alcohol-induced liver injury. Male and female Wistar rats (age- or weight-matched) were given ethanol (11-12 g.kg-1.day-1) continuously for up to 4 wk via intragastric feeding, and control rats received a high-fat diet without ethanol. There were no significant differences in body weight among the groups studied. Furthermore, mean ethanol concentrations, their cyclic pattern in urine, and rates of ethanol elimination were also not different between the genders under these conditions. Ethanol treatment elevated serum aspartate aminotransferase levels in male rats to 126 +/- 10 IU/l after 4 wk. In females, however, values increased more rapidly and reached significantly higher values at 4 wk (168 +/- 18 IU/l). Steatosis, inflammation, and necrosis assessed histologically also developed more rapidly and were more severe in females than males. Steatosis due to ethanol exposure, which was localized in centrilobular areas in males, was panlobular in the female. Moreover, endotoxin in plasma, intercellular adhesion molecule 1 expression in hepatic sinusoidal-lining cells, and the number of infiltrating inflammatory cells in the liver were 2-2.5-fold greater in females than males. These changes possibly account for increased hepatic injury due to ethanol in the female.
Can J Gastroenterol. 2000 Nov;14 Suppl D:129D-135D.
Sex-related liver injury due to alcohol involves activation of Kupffer cells by endotoxin.
Thurman RG.
Females have a greater susceptibility to ethanol-induced liver injury than males. Females who drink ethanol regularly and have been overweight for 10 years or more are at greater risk for both hepatitis and cirrhosis than males, and females develop ethanol-induced liver injury more rapidly and with less ethanol than males. Female rats on an enteral ethanol protocol exhibit injury more quickly than males and have widespread fatty changes over a larger portion of the liver lobule. Moreover, levels of plasma endotoxin, intracellular adhesion molecule-1, free radical adducts, infiltrating neutrophils and nuclear factor kappa B are doubled in female rat livers compared with male rat livers after enteral ethanol treatment. Additionally, estrogen treatment in vivo increases the sensitivity of hepatic macrophages or Kupffer cells to endotoxin. Evidence has been presented that Kupffer cells are pivotal in the development of ethanol-induced liver injury. Destroying Kupffer cells with gadolinium chloride or decreasing bacterial endotoxin by sterilizing the gut with antibiotics inhibits early inflammation due to ethanol. Similar results have been obtained with anti-tumour necrosis factor-alpha antibody. These data pointed to the hypothesis that ethanol-induced liver injury involves elevations in circulating endotoxin concentrations leading to activation of Kupffer cells, which causes a hypoxia-reoxygenation injury. This theory has been tested using pimonidazole, a 2-nitroimidazole marker, to quantify hypoxia in downstream, pericentral regions of the hepatic lobule. After chronic enteral ethanol treatment, pimonidazole binding doubles. Enteral ethanol also increases free radicals detected with electron spin resonance. Radical adducts, with coupling constants such as alpha-hydroxyethyl radical, have been shown to arise from ethanol. Importantly, hypoxia and radical production detected in bile are also decreased by the destruction of Kupffer cells with gadolinium chloride. These data support the hypothesis that Kupffer cells contribute to the vital sex differences in liver injury caused by ethanol.
J Gastroenterol Hepatol. 1998 Sep;13 Suppl:S39-50.
The role of gut-derived bacterial toxins and free radicals in alcohol-induced liver injury.
Thurman RG, Bradford BU, Iimuro Y, Knecht KT, Arteel GE, Yin M, Connor HD, Wall C, Raleigh JA, Frankenberg MV, Adachi Y, Forman DT, Brenner D, Kadiiska M, Mason RP.
Previous research from this laboratory using a continuous enteral ethanol (EtOH) administration model demonstrated that Kupffer cells are pivotal in the development of EtOH-induced liver injury. When Kupffer cells were destroyed using gadolinium chloride (GdCl3) or the gut was sterilized with polymyxin B and neomycin, early inflammation due to EtOH was blocked. Anti-tumour necrosis factor (TNF)-alpha antibody markedly decreased EtOH-induced liver injury and increased TNF-mRNA. These findings led to the hypothesis that EtOH-induced liver injury involves increases in circulating endotoxin leading to activation of Kupffer cells. Pimonidazole, a nitro-imidazole marker, was used to detect hypoxia in downstream pericentral regions of the lobule. Following one large dose of EtOH or chronic enteral EtOH for 1 month, pimonidazole binding was increased significantly in pericentral regions of the liver lobule, which was diminished with GdCl3. Enteral EtOH increased free radical generation detected with electron spin resonance (ESR). These radical species had coupling constants matching alpha-hydroxyethyl radical and were shown conclusively to arise from EtOH based on a doubling of the ESR lines when 13C-EtOH was given. Alpha-hydroxyethyl radical production was also blocked by the destruction of Kupffer cells with GdCl3. It is known that females develop more severe EtOH-induced liver injury more rapidly and with less EtOH than males. Female rats on the enteral protocol exhibited more rapid injury and more widespread fatty changes over a larger portion of the liver lobule than males. Plasma endotoxin, ICAM-1, free radical adducts, infiltrating neutrophils and transcription factor NFkappaB were approximately two-fold greater in livers from females than males after 4 weeks of enteral EtOH treatment. Furthermore, oestrogen treatment increased the sensitivity of Kupffer cells to endotoxin. These data are consistent with the hypothesis that Kupffer cells participate in important gender differences in liver injury caused by ethanol.
Journal of Hepatology 35 (2001) 130±133
Alcoholic liver disease: a matter of hormones?
Han Moshage
