Fat and Viral Liver Disease

Transcription

1 Fat and Viral Liver Disease Francesco Negro Viropathology Unit University of Geneva Medical Center Geneva, Switzerland Mainz, September 20, 2008

2 Steatosis and HBV

3 Steatosis in HBV infection: prevalence and correlates n Steatosis Correlates Thomopoulos 2006* (18%) BMI, fasting glucose (MV) Altlparmak 2005* (39%) Gordon (53%) Age, BMI, cholesterol, triglycerides (UV) C-peptide, glucose, waist circumference (MV) *Patients with and without steatosis were comparable in terms of HBV DNA levels

4 Steatosis and HCV

5 Histopathological features of chronic non-a, non-b hepatitis Feature Prevalence Cell ballooning 89% Nuclear modifications 88% Eosinophilic cytoplasm 73% Focal sinusoidal activation 92% Steatosis 59% "Follow-up analysis showed that there were no changes of these criteria up to the 6th year of disease" WIESE & HAUPT, Dtsch Z Verdau Stoffwechselkr 1985;45:

6 Prevalence of Steatosis in Chronic Hepatitis C Steatosis occurs in: ~50% of chronic hepatitis C patients, overall considered HOURIGAN et al, Hepatology 1999;29:1215 LEANDRO et al, Gastroenterology 2006;130:1636 ~40% of chronic hepatitis C patients without known factors of fatty liver (overweight, alcohol drinking, drugs, dyslipidemia) RUBBIA-BRANDT et al, J Hepatol 2000;33:106 ~20% of chronic hepatitis B patients CZAJA et al, J Hepatol 1998;29:198 THOMOPOULOS et al, Eur J Gastroenterol Hepatol 2006;18:233

7 Steatosis is a cytopathic effect of HCV 1 Occurrence and severity of steatosis is associated with genotype 3 MIHM et al, 1997; RUBBIA-BRANDT et al, 2000; ADINOLFI et al, 2001 KUMAR et al, 2002; MONTO et al, 2002; POYNARD et al, 2003 HOFER et al, 2002; WESTIN et al, The score of steatosis correlates with the level of HCV RNA in serum and liver, but only in patients with genotype 3 RUBBIA-BRANDT et al, 2000; ADINOLFI et al, Virological response to α-ifn is associated with the disappearance of the steatosis, which recurs at the time of virological relapse RUBBIA-BRANDT et al, 2001; KUMAR et al, 2002; POYNARD et al, 2003

8 Triglycerides levels in HCV-transfected vs. untransfected Huh-7 cells O. D b 2a 3a 3h 4h 5a GFP ABID et al, J Hepatol 2005;42:

9 Triglycerides levels in HCV-transfected vs. untransfected Huh-7 cells ~3-fold O. D b 2a 3a 3h 4h 5a GFP ABID et al, J Hepatol 2005;42:

10 Liver steatosis in hepatitis C: proposed mechanisms - 1 Decreased lipoprotein secretion via inhibition of the MTP activity PERLEMUTER et al, FASEB J 2002 via non-specific inhibition of secretory pathways by ROS via downregulation of MTP Decreased degradation OKUDA et al, Gastroenterology 2002 LERAT et al, Gastroenterology 2002 MIRANDOLA et al, Gastroenterology 2006 in mitochondria, via downregulation of CPT-1 YAMAGUCHI et al, Dig Dis Sci 2005

11 HCV core protein transgenic mouse TG Apo B VLDL assembly impaired VLDL secretion MTP HCV core protein intracytoplasmic TG storage STEATOSIS PERLEMUTER et al, FASEB J 2002;16:185

12 Intrahepatic MTP mrna levels are inversely correlated with steatosis scores Intrahepatic MTP mrna levels P = steatosis score MIRANDOLA et al, Gastroenterology 2006;130:1661-9

13 Serum lipid profile changes in HCV In chronic hepatitis C, Apolipoprotein B levels: are inversely correlated with steatosis score revert to normal upon response to therapy SERFATY et al, J Hepatol 2001;34:428 HCV type 3a lowers serum cholesterol levels: HCV 1 HCV 3 HCV 4 P 188 ± ± ± 35 <0.01 Hypocholesterolemia in genotype 3a: returns to normal in sustained virological responders is not shared by other HCV genotypes HOFER et al, Am J Gastroenterol 2002;97:2880

14 Liver steatosis in hepatitis C: proposed mechanisms - 2 Increased ex novo synthesis of fatty acids via activation of RxRα TSUTSUMI et al, Hepatology 2002 via enhanced LXRa/RxRα binding to LXR-RE in a PA28γdependent manner MORIISHI et al, Proc Natl Acad Sci USA 2007 via upregulation of sterol responsive element binding protein (SREBP)-1c SU et al, Proc Natl Acad Sci USA 2002 WARIS et al, J Virol 2007 JACKEL-CRAM et al, J Hepatol 2007

15 HCV induces lipogenic enzymes in Huh-7 WARIS et al, J Virol 2007;81:

16 What is the HCV sequence responsible for TG accumulation?

17 1 50 1b MSTNPKPQRK TKRNTNRRPQ DVKFPGGGQI VGGVYLLPRR GPRLGVRAPR 2a MSTNPKPQRK TKRNTNRRPQ DVKFPGGGQI VGGVYLLPRR GPRLGVRATR 3a MSTLPKPQRK TKRNTIRRPQ DVKFPGGGQI VGGVYVLPRR GPRLGVCATR 3h MSTLPKPQRK TKRNTIRRPQ NVKFPGGGQI VGGVYVLPRR GPTLGVRAAR 4h MSTNPKPQRK TKRNTNRRPM DVKFPGGGQI VGGVYLLPRR GPRLGVRATR 5a MSTNPKPQRK TKRNTSRRPQ DVKFPGGGQI VGGVYLLPRR GPRMGVRATR b KTSERSQPRG RRQPIPKARR PEGRTWAQPG YPWPLYGNEG MGWAGWLLSP 2a KTSERSQPRG RRQPIPKDPR STGRSWGRPG YPWPLYGNEG LGWAGWLLSP 3a KTSERSQPRG RRQPIPKARR SEGRSWAQPG YPWPLYGNEG CGWAGWLLSP 3h KTSERSQPRG RRQPIPKARR NEGRTWAQPG YPWSLYGNEG CGWAGWLLSP 4h KTSERSQPRG RRQPIPKARP SEGRSWAQPG YPWPLYGNEG CGWAGWLLSP 5a KTSERSQPRG RRQPIPKARQ STGRSWGQPG YPWPLYANEG LGWAGWLLSP b RGSRPSWGPT DPRRRSRNLG KVIDTLTCGF ADLMGYIPLV GAPLGGAARA 2a RGSRPSWGPT DPRHRSRNLG KVIDTLTCGF ADLMGYIPVV GAPVGGVARA 3a RGSRPSWGPN DPRRRSRNLG KVIDTLTCGF ADLMGYIPLV GAPVGGVARA 3h RGSRPHWGPN DPRRRSRNLG KIIDTLTCGF ADLMGYIPLV GAPVGGVARA 4h RGSRPSWGPN DPRRRSRNLG KVIDTLTCGF ADLMGYIPLV GAPVGGVARA 5a RGSRPNWGPN DPRRRSRNLG KVIDTLTCGF ADLMGYIPLV GGPVGGVARA 1b LAHGVRVLED GVN YATG NLP GCSFSIFLLA LLSCLTIPAS A a LAHGVRVLED GIN YATG NLP GCSFSIFLLA LLSCISVPVS A 3a LAHGVRALED GIN FATG NLP GCSFSIFLLA LFSCLVHPAA S 3h LAHGVRAVED GIN YATG NLP GCSFSIFLLA ILSCLTVPAS G 4h LAHGVRALED GIN YATG NLP GCAFSIFLLA LLSCLTVPAS A 5a LAHGVRALED GVN YATG NLP GCSFSIFILA LLSCLTVPAS A

18 HOURIOUX et al, Gut 2007;56: The HCV-3a triglyceride accumulation is due to a Y164F mutation within the core D2 domain Core 1a Core 1a Y164F

19 F164Y is responsible for FAS activation by HCV 3a core JACKEL-CRAM et al, J Hepatol 2007;46:

20 HCV-induced steatosis: 1) Why? 2) Does it matter?

21 HCV core and NS5A proteins colocalize with lipid droplets in hepatocytes LD are physiological structures of fat storage in hepatocytes Colocalization is an essential step for virion assembly The domain 2 (D2), especially A147V, has a critical role in the core-ld interaction and allows efficient virion assembly SHAVINSKAYA et al, J Biol Chem 2006;282: Dysruption of the domain 2 (D2) of the core and of domain III of NS5A abrogate colocalization to LD and assembly of infectious particles BOULANT et al, J Biol Chem 2006;281: APPEL et al, PLoS Pathog 2008;4:e

22 HCV core and NS5A colocalize with LD and direct virion assembly APPEL et al, PLoS Pathog 2008;4:e

23 HCV core colocalization with LD occurs independently of its steatogenic effects PIODI et al, Hepatology 2008;48:16-27

24 What is better for HCV: 1,000,000 small lipid droplets or 1 big steatosis droplet? 1,000,000 lipid droplets (each Ø 0.1 μm) 4,187 μm 3 125,600 μm 2 One steatosis droplet (Ø 10 μm) 4,187 μm 3 1,256 μm 2

25 The HCV MAID Study Predictors of fibrosis (n = 3,068) All pts. HCV genotype BMI < >30 n Activity NS Male gender NS NS NS NS Steatosis NS NS NS 1.61 NS NS Age NS 1.05 NS Genotype NS NS NS Diabetes NS 4.52 NS NS NS NS NS NS Alcohol abuse NS NS NS NS NS NS 1.69 NS LEANDRO et al, Gastroenterology 2006

26 Steatosis at baseline and SVR P=0.33 P< non-3 1, 4, 5, 6 Steatosis No steatosis P<0.001 (n = 134) (n = 900) (n = 746) POYNARD et al, Hepatology 2003;38:75-85

27 Steatosis follows insulin resistance, not the other way around FARTOUX et al, Gut 2005;54:

28 HCV-induced steatosis Summary - 1 Steatosis in hepatitis C is significantly associated with genotype 3a In patients with HCV 3a, TG accumulation correlates with viral load and pattern of response to therapy, and seems to be due to impaired VLDL secretion + ex novo lipogenesis The sequence responsible for TG accumulation may be the Y/F polymorphism at residue 164

29 HCV-induced steatosis HCV induced steatosis: Summary - 2 is NOT associated with increased liver fibrosis is NOT associated with reduced response to IFN-α is NOT associated with increased insulin resistance is unlikely to benefit HCV replication or assembly it may only have diagnostic significance

30 In chronic viral liver disease, is steatosis ALWAYS due to the virus?

31 Steatosis in chronic hepatitis B Steatosis (n=42)* No steatosis (n=191) p Male gender 28 (66.7%) 136 (71.2%) NS Age 46.2 ± ± 16.7 NS HBV DNA (cp x 10 6 ) 55.5 ± ± 127 NS Activity 7 17 (40.5%) 66 (34.6%) NS Fibrosis 3 17 (40.5%) 77 (40.3%) NS BMI (71.4%) 83 (43.5%) Fasting glucose** ± ± Cholesterol** ± ± 47.2 NS Triglycerides** ± ± 73.1 NS * Moderate to heavy alcohol drinkers were excluded; ** mg/dl THOMOPOULOS et al, Eur J Gastroenterol Hepatol 2006;18:233-7

32 HCV-unrelated steatosis In most chronic hepatitis C patients who have non-3a genotype infection and who do not drink alcohol: Severity of steatosis correlates with the body mass index (and not with HCV RNA level), hence the steatosis is «metabolic» ADINOLFI et al, 2001 The steatosis occurrence and severity is not (or only partially) modified by successful antiviral treatment KUMAR et al, 2002; POYNARD et al, 2003

33 Metabolic steatosis is due to insulin resistance BROWNING & HORTON, J Clin Invest 2004;114:147

34 Risk factors for steatosis in 44 non-3a, alcohol abstinent chronic hepatitis C patients no risk factors 30% 20% BMI >25 32% 18% HOMA >2 BMI >25 / HOMA >2 MUZZI et al, J Hepatol 2005;42:41-46

35 The HCV MAID Study Predictors of fibrosis (n = 3,068) All pts. HCV genotype BMI < >30 n Activity NS Male gender NS NS NS NS Steatosis NS NS NS 1.61 NS NS Age NS 1.05 NS Genotype NS NS NS Diabetes NS 4.52 NS NS NS NS NS NS Alcohol abuse NS NS NS NS NS NS 1.69 NS LEANDRO et al, Gastroenterology 2006

36 Fibrogenesis in Chronic Hepatitis C: Steatosis or Insulin Resistance? By MV, the HOMA score (but not steatosis) is a factor independently associated with fibrosis score (P<0.001) and with its progression rate (P=0.03) HUI et al, Gastroenterology 2003 Insulin resistance and/or diabetes are associated with severity of fibrosis RATZIU et al, 2003; HUI et al, 2003; FARTOUX et al, 2005 MUZZI et al, 2005; LEANDRO et al, 2006

37 Steatosis at baseline and SVR P=0.33 P< non-3 1, 4, 5, 6 Steatosis No steatosis P<0.001 (n = 134) (n = 900) (n = 746) POYNARD et al, Hepatology 2003;38:75-85

38 Insulin resistance decreases SVR in chronic hepatitis C (genotype 1) ROMERO-GOMEZ et al, Gastroenterology 2005;128:

39 Insulin resistance decreases SVR in chronic hepatitis C (genotypes 2 and 3) 100 χ 2 = 9.752, p<0.001 % SVR <2 2-4 >4 HOMA-IR score POUSTCHI et al, J Hepatol 2008;48:28-34

40 Increasing insulin sensitivity in chronic viral liver disease Increase physical activity Reduce body weight Insulin sensitizers Metformin Thiazolidindiones

41 Fat and viral liver disease Clinical management summary HCV-induced steatosis seems an innocent bystander, and disappears with successful antiviral therapy The management of steatosis unrelated to HBV/HCV is the management of its cause: In case of alcohol abuse, treat alcohol abuse In case of metabolic syndrome, insist on lifestyle changes