Alcoholic Liver 2005 Ust

ALCOHOLIC FATTY LIVER DISEASE Diana Alcantara-Payawal, MD

Histologic Spectrum NORMAL 90-100 %

FAT

Fatty Liver

10- 35 %

8-20%

Fat + Inflam +/Fibrosis Alcoholic Hepatitis

Scar + Nodules +/Fat

? 40%

Cirrhosis

Risk factors for alcoholic liver disease: •Quantity •Gender •Hepatitis C: Accelerated disease progression, more advanced histology and decreased survival rates •Genetics: alcohol dehydrogenase, acetaldehyde dehydrogenase •Malnutrition:

Major forms of alcoholic liver disease: •Fatty liver •Alcoholic hepatitis •Cirrhosis Time to develop liver disease = to amount of alcohol consumed One beer, 4 ounces of wine, one ounce of 80% spirits = 12 grams of alcohol Men:60-80 gm/day for 10 years Women 20-40 gm/day for 10 years

Women’s Risk of ALD Women alcoholics begin drinking later, and drink less alcohol per day than men Women drink for fewer years than men and have a lower cumulative alcohol exposure at the time of diagnosis of cirrhosis Women die of ALD at a 10 year earlier age than men.

Susceptibility of females to hepatotoxicity of ethanol More pronounced fatty liver Less induction of fatty acid binding protein (higher FFA) Increased plasma endotoxin levels Increased CD 13 and LBP More severe pericentral hypoxia More marked activation of NfkB

Enzymatic pathways of ethanol metabolism ADH

ALDH

NAD+ NADH

NAD+ NADH

Ethanol

Acetaldehyde CYP2E1

Acetaminophen CCl4

Toxic metabolites, reactive oxygen species

Acetate

Update of the VA Twin Panel Study 15,924 twins followed until 1994 Concordance (%)

Alcoholism Psychosis Cirrhosis

MZ

DZ

28.7 17.3 16.9

12.2 4.8 5.3

However, most of the genetic liability to develop cirrhosis was the result of shared genetic liability for alcoholism.

Traditional model of pathogenesis of fatty liver Ethanol increases NADH level inhibiting enzymes of fatty acid oxidation. Ethanol increases synthesis of fatty acids associated with induction of lipogenic enzymes.

New mechanism for control of lipid metabolism

FFA

+

+ PPAR/RXR

Induction of FFA oxidation, transport and export genes

Peroxisome proliferator activated receptor

Sterol

-

SREBP

+

Sterol response element binding protein

Induction of sterol/fat synthesizing genes

New mechanism for control of lipid metabolism

FFA Ethanol

+ -

+

Induction of FFA oxidation, transport and export genes

+

Induction of sterol/fat synthesizing genes

PPAR/RXR

+ Sterol

-

SREBP

Hepatic Fatty Acid Metabolism FFA HOOC(CH2)NCH3 Triglycerides PL,CE

Mitochondrial B Oxidation CPT-1

L-FABP FFA

Microsomal B Oxidation Peroxismal B Oxidation CYP4A1 AOX HOOC(CH2)NCH3

Hepatic Fatty Acid Metabolism FFA HOOC(CH2)NCH3 Triglycerides PL,CE LIPID PEROXIDATION

Mitochondrial B Oxidation CPT-1

L-FABP FFA

CYTOTOXICITY

Microsomal B Oxidation Peroxismal B Oxidation CYP4A1 AOX HOOC(CH2)NCH3

Hepatic Fatty Acid Metabolism FFA HOOC(CH2)NCH3

Mitochondrial B Oxidation CPT-1

Triglycerides PL,CE

L-FABP FFA

PPAR a

TRANSACTIVATION

Microsomal B Oxidation Peroxismal B Oxidation CYP4A1 AOX HOOC(CH2)NCH3

Effects of ethanol on protein metabolism ETHANOL

Acetaldehyde, HER +

Protein adducts

Enzyme, cytoskeleton, membrane protean malfunction, neoantigen formation Inhibition of proteoasomal proteases, protein accumulation, cell swelling abnormal signaling

Ethanol and acetaldehyde

HC

ROS TNFa

KC

ROS TNFa TGFb IL-6 IL-1 TXA2

HSC

EC

Activating Injury factors Death Fibrogenesis (necrosis, Adhesio Inflammation; apoptosis) n Hypoxia Molecul e cytokine s

Activation of HSC Irreversible activation maybe mediated by HSC products, retinoid depletion, and changes in the matrix ECM protein collagen I, fibronectin TGFB Activated HSC

Sources of reactive oxygen species in ethanol treated liver cells Endoplasmic reticulum NADPH + O2 Ethanol CYP2E1 ADH Acetaldehyde ROS

Mitochondria

NADH O2 E TC ROS H2O

Reductive stress

Consequence of oxidant stress Superoxide

Hydrogen peroxide

Hydroxyl radica

Attack of polyunsaturated fatty acids Lipid hydroperoxide Lipid radicals Lipid decomposition

Interactions of ethanol and endotoxin FIRST HIT Ethanol Kupffer cell Endotoxin Scavenger receptor CD14

Activation of Kupffer cell

LBP Endotoxin Second Hit

Ethanol induces LBP and CD14

Activation of Hepatic Stellate Cells

The very earliest event in HSC activation is unknown

Matrix changes ? Activation of NF kB Via degradation of IkB

Receptors present TNFa, IL-1

Induction of PDGFR, TGFB-Rs, ICAM-1

Consequences of Kupffer cell activation by ethanol

Activated Kupffer Cell

Cytokines TNFa IL-1, IL-6 PDGF Eicosanoids ROS MIP2, IL-8

CHRONIC ETHANOL INGESTION Lipid peroxidation Acetaldehyde Aldehydes

MAA adducts

Stellate cell

Autoantibodies

Collagen

Autoimmun e response

Fibrotic response

CHRONIC ETHANOL INGESTION Lipid peroxidation

Intestine + Endotoxin

Protein Acetaldehyde adducts

Aldehydes Hepatocyte PPARg/RXR MAA adducts

Stellate cell

Autoantibodies

Collagen

Autoimmun e response

Fibrotic response

Kuppfer cells TNF-a TGF-B IL-1 IL-6

Inflammatory Response

Laboratory findings Increased GGT :Not specific to alcohol, easily inducible, elevated in all forms of fatty liver Macrocytosis (Increased PMN). If >5500/uL predictws asevere alcoholic hepatitis when discriminatory index is >32 AST>ALT by 2 fold High CDT High gamma globulin (IgA) High uric acid High serum lactate Low albumin Low protime High triglycerides

Maddrey’s discriminatory function 4.6(protime- control in seconds) + bilirubin (umol/L)/17 >32 assess severity of AH Alcoholic hepatitis has poor prognosis

Presence of ascites, variceal hemmorrhage, deep encephalopathy or hepatorenal syndrome has dismal prognosis

Lifestyle modification EtOH intake Obesity Smoking

ABSTINENCE IMPROVES SURVIVAL OF ALCOHOLIC CIRRHOSIS SURVIVAL

120 100

ABSTINENCE

80 60 40 20 0 TIME OF OBSERVATION

Management of ALD

Abstinence and aggressive nutritional support Traditional nutritional supplement clearly improves nutritional status, hepatic function, and outcome in AH/ cirrhosis Hepatology, 2000

Cigarette smoking is an independent risk factor for cirrhosis in ALD Am J Epidemiology, 1994 Eur J of EWpidemiology, 1994

Management of ALD Propylthiouracil Attenuates the hypermetabolic state to have antioxidant properties and improve portal blood flow. No significant effects of PTU vs placebo on mortality, complications of liver disease or liver histology Cochrane review of 6RCT

Management of ALD Colchicine Anti-fibrotic effects, inhibition of collagenase activity and antiinflammatory functions. No beneficial effect on with overall mortality or liver related mortality. Morgan, Gastroenterology, 2002

Management of ALD Corticosteroid Decrease the immune response and proinflammatory cytokine response They should be reserved for those with severe liver disease (DF >31), and hepatic encephalopathy. Carithers, Ann Int Med, 1989 Mendenhall, NEJM, 1984

Management of ALD Pentoxifylline (TRENTAL) •Nonselective phosphodiesterase which increases intracellular concentration of cAMP and cGMP •Decreases pro-inflammatory cytokines including TNFa •Improved vascular microcirculation •Decreased leucocyte adhesion factor •Antifibrotic

Pentoxyfylline vs placebo in AH PTX-Tx

Placebo PTX-tx

PTX 400 mg TID vs vitamin B 12 for 4 weeks –improved short term survival Akriviadis, Gastroenterology, 2000

Management of ALD Vitamin E Membrane stabilization, reduced NFkB activation and TNF production, inhibition of stellate cell activation and collagen production. JCI, 1995 No benefit and likely due to inadequate dose J AM Nutrition, 1995

Management of ALD SAMe Precursor for the synthesis of polyamines, choline and GSH Obligatory intermediate in conversion of methionine and cysteine in the hepatic transulfuration pathway. 1200 mg daily for 2 years- showed potential benefit J Hepatology, 1999 JCI, 1995

Management of ALD GSH Modulate proinflammatory cytokine production with inhibition of cytokines TNFa and IL-8. Clin Biochem 1999

ALOCHOLIC HEPATITIS Alcoholic abstinence Nutritional support Discriminatory function >32 (with absence of comorbidity) TREATMENT OPTIONS Preferred Prednisilone 32 mg PO Daily for 4 weeks then taper for 4

Alternative Pentoxifylline 400 mg PO TID for 4 weeks

Proposed Pathophysiology Insulin Resistance Hyperinsulinemia Liver Resistant Glucose productio n

Sensitive

Periphery Resistant

Lipid export Lipid peroxidation B oxidation

FFA

Hepatic Steatosis

LEAF PATHWAYS Carnitine Acyl group Carnitine

Carnitine

Fatty acid Carnitine CPT1

Fatty Acid Carnitine FA+CoA B oxidation

TRANSPORT AND OXIDATION OF FATTY ACID IN THE MITOCHONDRIA

Energy Production ATP Protection of the Cell Membrane

ALCOHOLIC FATTY LIVER DISEASE Diana Alcantara-Payawal, MD

METABOLITES Lipid peroxidation Ethanol

ADH

A-amino-N-Butyrate

Free radicals

Microsomes (CYP2E)

GSH

cysteine

Acetaldehyde

methionine MAT

A ketobutyrate

cystathionine homocysteine

serine

S-adenosylmethionine phosphatidylcholine Phosphatidylethanolamine

METABOLITES Lipid peroxidation Ethanol

ADH

A-amino-N-Butyrate

Free radicals

GSH alpha ketobutyrate

Microsomes (CYP2E)

cysteine

Acetaldehyde

methionine

cystathionine homocysteine

serine

S-adenosylmethionine phosphatidylcholine Phosphatidylethanolamine

cyp

MITO ROS

Lipid peroxidation

FAT DEPOSITS

Increased glucose/insulin Sustained lipolysis

Increased FFA

Increased FFA synthesis

Increased fat deposits

Increased hepatic FFA pool

Increased triglyceride pool

Increased B oxidation

Increased triglyceride secretion

Increased glucose/insulin Sustained lipolysis

Increased FFA

Increased FFA synthesis

Increased fat deposits

Increased hepatic FFA pool

Increased triglyceride pool

Increased B oxidation

Increased triglyceride secretion

Spectrum of alcoholic liver disease 8-20%

RECOVERY

death cirrhosis Death >50% SAH SAH

40%

Fatty liver AH RECOVERY

10-35%

Social Drinking

Alcohol Liver Disease

FAT Steatosis

Injury and inflammation Steatohepatitis fibrosis 0

+4

cirrhosis

HCC

Histologic Spectrum

FAT

Fatty Liver Steatosis

NASH

Cirrhosis Fat + Inflam +/Fibrosis

Scar + Nodules +/Fat

Mild Hepatocellular Normal function Histology Steatosis

Moderate

Severe disease

Moderately impaired

Hepatocellular failure

Marked SH, mallory bodies, advanced cirrhosis RUQ pain Hepatosplenomegaly Mild jaundice with PH

Marked SH, mallory bodies, advanced cirrhosis RUQ pain,fever Hepatosplenomegaly Deep jaundice with PH

Clinical symptoms

Asymptomatic

Outcome

Fully reversible Potentially reversible on alcohol abstinence

Potentially improvement on alcohol abstinence

Steatosis

Innocent bystander

Guilty Party

1st hit

Steatosis (vulnerable)

Normal Oxidativ e Stress

2nd hit

Steatohepatitis

Two-hit hypothesis of NASH

Stasis

NAFLD

Insulin Resistanc e TNFa IkkB

ETOH TNFa

Liver Mesenteric Fat

Intestinal Bacterial Overgrowth

FATTY LIVER Hepatic triglyceride synthesis

Hepatic triglyceride secretion

Stellate cell

Anti-viral agents Abstinence from alcohol Removal of Iron, Copper and toxic salts Anti-inflammatory agents

INJURY

Quiescent

Activated

Rich in retinoid Few smooth muscle proteins Little extracellular matrix Receptors Little proliferation

Decreased retinoid acitivity Multiple smooth muscle protein Abundant extracellular matrix Increased receptor density Marked proliferation

Polyunsaturated soybean lecithin containing: 55%-60% phosphatidylcholine Highly purified PC fraction with an exceptionally high content of essential fatty acids: 70% linoleic acid 10% linolenic acid 5% monounsaturated oleic acid 15% saturated fatty acid

EPL reduces fibrogenesis: direct effect on stellate cell activation lipid peroxidation Aleynik, 1997 Promotes breakdown of collagen Gastroenterology, 1994

PPC at 1.5 gm /day vs placebo Decrease 4 plasma markers of oxidative stress No change or presence of regression of fibrosis on liver biopsy Leiber, 2000

METABOLITES Lipid peroxidation Ethanol

ADH

A-amino-N-Butyrate

Free radicals

Microsomes (CYP2E)

GSH

cysteine

Acetaldehyde

methionine

A ketobutyrate

cystathionine homocysteine

serine

S-adenosylmethionine phosphatidylcholine Phosphatidylethanolamine

Healthy liver

Cirrhosis

Hepatic fibrosis

Liver cancer

The basic purpose is to heal…and do no harm!!!

Anti-viral agents Abstinence from alcohol Removal of Iron, Copper and toxic salts Anti-inflammatory agents

Parenchyma inflammation Ischemic collapse of the liver tissue Parenchymal Extinction Progressive vascular occlusion thrombosis

Anti-thrombotic agents Vasodilators

Persistent fibrosis Cirrhosis

Hepatic Cell membrane: Represents vital morphological structure of every organism Essential components of cellular and subcellular membranes: 65% hepatocells or liver parenchyma 80% of liver parenchyma is membrane 60-65% of liver cell membrane is phospholipids 70-90% is EPL

Phospholipids serves as hinges between cellbreathing enzymes and mitochondrial crest

Choline Phosphate glycerol

EPL: Make membranes more fluid and active enhancing permeability Activates membrane located phospholipids dependent membranes