Abstract
Ethanol-induced hepatic steatosis may induce the progression of alcoholic liver disease. The involvement of autophagic clearance of damaged mitochondria (mitophagy) and lipid droplets (LDs) (lipophagy) in chronic ethanol-induced hepatic steatosis is not clearly understood. Adult Wistar rats were fed either 5 % ethanol in Lieber-DeCarli liquid diet or an isocaloric control diet for 10 weeks. Light microscopy showed marked steatosis in hepatocytes of ethanol-treated rats (ETRs), which was further revealed by transmission electron microscopy (TEM), where significant numbers of large LDs and damaged mitochondria were detected in steatotic hepatocytes. Moreover, TEM demonstrated that hepatocyte steatosis was associated with greatly enhanced autophagic vacuole (AV) formation compared to control hepatocytes. Mitochondria and LDs were the predominant contents of AVs in steatotic hepatocytes. Immunohistochemistry of LC3, a specific marker of early AVs (autophagosomes), demonstrated an extensive punctate pattern in hepatocytes of ETRs, while LC3 puncta were much less frequent in control hepatocytes. This was confirmed by immunoelectron microscopy (IEM), which showed localization of LC3 to autophagosomes sequestering damaged mitochondria and LDs. In addition, IEM revealed that PINK1 (a sensor of mitochondrial damage and marker of mitophagy) was overexpressed in mitochondria of ETRs. Enhanced autophagic lysosomal activity was evidenced by increased immunolabeling of LAMP-2, a marker of late AVs (autolysosomes) in hepatocytes of ETRs and colocalization of LC3 and lysosomal cathepsins using double immunofluorescence labeling. Increased AVs in hepatocytes of ETRs reflect ethanol toxicity and could represent a possible protective mechanism via stimulation of mitophagy and lipophagy.
Similar content being viewed by others
References
Back JH, Zhu Y, Calabro A, Queenan C, Kim AS, Arbesman J, Kim AL (2012) Resveratrol-mediated downregulation of rictor attenuates autophagic process and suppresses UV-Induced skin carcinogenesis. Photochem Photobiol 88(5):1165–1172
Barth S, Glick D, Macleod KF (2010) Autophagy: assays and artifacts. J Pathol 221:117–124
Berthier A, Navarro S, Jiménez-Sáinz J, Roglá I, Ripoll F, Cervera J, Pulido R (2011) PINK1 displays tissue-specific subcellular location and regulates apoptosis and cell growth in breast cancer cells. Hum Pathol 42:75–87
Chacko BK, Srivastava A, Johnson MS, Benavides GA, Chang MJ, Ye Y, Jhala N, Murphy MP, Kalyanaraman B, Darley-Usmar VM (2011) Mitochondria-targeted ubiquinone (MitoQ) decreases ethanol-dependent micro and macro hepatosteatosis. Hepatology 54(1):153–163
Chu CT (2010) A pivotal role for PINK1 and autophagy in mitochondrial quality control: implications for Parkinson disease. Hum Mol Genet 19:R28–R37
Cordero MD, De Miguel M, Moreno Fernández AM, Carmona López IM, Garrido Maraver J, Cotán D, Gómez Izquierdo L, Bonal P, Campa F, Bullon P, Navas P, Sánchez Alcázar JA (2010) Mitochondrial dysfunction and mitophagy activation in blood mononuclear cells of fibromyalgia patients: implications in the pathogenesis of the disease. Arthritis Res Ther 12:R17. doi:10.1186/ar2918
Czaja MJ (2010) Autophagy in health and disease. 2. Regulation of lipid metabolism and storage by autophagy: pathophysiological implications. Am J Physiol Cell Physiol 298(5):C973–C978
Czaja MJ (2011) Functions of autophagy in hepatic and pancreatic physiology and disease. Gastroenterol 140:1895–1908
Czaja MJ, Cuervo AM (2009) Lipases in lysosomes, what for? Autophagy 5(6):866–867
Dagda RK, Zhu J, Kulich SM, Chu CT (2008) Mitochondrially localized ERK2 regulates mitophagy and autophagic cell stress: implications for Parkinson’s disease. Autophagy 4:770–782
Ding WX, Yin XM (2012) Mitophagy: mechanisms, pathophysiological roles, and analysis. Biol Chem 393:547–564
Ding WX, Li M, Chen X, Ni HM, Lin CW, Gao W, Lu B, Stolz DB, Clemens DL, Yin XM (2010) Autophagy reduces acute ethanol-induced hepatotoxicity and steatosis in mice. Gastroenterol 139:1740–1752
Ding WX, Li M, Yin XM (2011a) Selective taste of ethanol-induced autophagy for mitochondria and lipid droplets. Autophagy 7:248–249
Ding WX, Manley S, Ni HM (2011b) The emerging role of autophagy in alcoholic liver disease. Exp Biol Med 236:546–556
Dolganiuc A, Thomes PG, Ding WX, Lemasters JJ, Donohue TM Jr (2012) Autophagy in alcohol-induced liver diseases. Alcohol Clin Exp Res 36(8):1301–1308
Dong H, Czaja MJ (2011) Regulation of lipid droplets by autophagy. Trends Endocrinol Metab 22:234–240
Eid NA, Shibata MA, Ito Y, Kusakabe K, Hammad H, Otsuki Y (2002) Involvement of Fas system and active caspases in apoptotic signalling in testicular germ cells of ethanol-treated rats. Int J Androl 25:159–167
Eid N, Ito Y, Otsuki Y (2012) Enhanced mitophagy in Sertoli cells of ethanol-treated rats: morphological evidence and clinical relevance. J Mol Histol 43:71–80
Eskelinen EL (2008) To be or not to be? Examples of incorrect identification of autophagic compartments in conventional transmission electron microscopy of mammalian cells. Autophagy 4:257–260
Eskelinen EL, Illert AL, Tanaka Y, Schwarzmann G, Blanz J, Von Figura K, Saftig P (2002) Role of LAMP-2 in lysosome biogenesis and autophagy. Mol Biol Cell 13:3355–3368
Feldstein AE, Bailey SM (2011) Emerging role of redox dysregulation in alcoholic and nonalcoholic fatty liver disease. Antioxid Redox Signal 15:421–424
Fortunato F, Burgers H, Bergmann F, Rieger P, Büchler MW, Kroemer G, Werner J (2009) Impaired autolysosome formation correlates with Lamp-2 depletion: role of apoptosis, autophagy, and necrosis in pancreatitis. Gastroenterol 137:350–360
Fujii S, Mitsunaga S, Yamazaki M, Hasebe T, Ishii G, Kojima M, Kinoshita T, Ueno T, Esumi H, Ochiai A (2008) Autophagy is activated in pancreatic cancer cells and correlates with poor patient outcome. Cancer Sci 99:1813–1819
Fujimoto T, Ohsaki Y (2006) Cytoplasmic lipid droplets: rediscovery of an old structure as a unique platform. Ann NY Acad Sci 1086:104–115
Gao B, Bataller R (2011) Alcoholic liver disease: pathogenesis and new therapeutic targets. Gastroenterology 141:1572–1585
Gordon ER (1973) Mitochondrial functions in an ethanol-induced fatty liver. J Biol Chem 248(23):8271–8280
Hah YS, Noh HS, Ha JH, Ahn JS, Hahm JR, Cho HY, Kim DR (2012) Cathepsin D inhibits oxidative stress-induced cell death via activation of autophagy in cancer cells. Cancer Lett 323(2):208–214
Holt SV, Wyspianska B, Randall KJ, James D, Foster JR, Wilkinson RW (2011) The development of an immunohistochemical method to detect the autophagy-associated protein LC3-II in human tumor xenografts. Toxicol Pathol 39:516–523
Iseri OA, Lieber CS, Gottlieb LS (1966) The ultrastructure of fatty liver induced by prolonged ethanol ingestion. Am J Pathol 48(4):535–555
Itakura E, Kishi-Itakura C, Koyama-Honda I, Mizushima N (2012) Structures containing Atg9A and the ULK1 complex independently target depolarized mitochondria at initial stages of Parkin-mediated mitophagy. J Cell Sci 15(125):1488–1499
Jin SM, Youle RJ (2012) PINK1- and Parkin-mediated mitophagy at a glance. J Cell Sci 125:795–799
Kanthasamy A, Anantharam V, Ali SF, Kanthasamy AG (2006) Methamphetamine induces autophagy and apoptosis in a mesencephalic dopaminergic neuronal culture model: role of cathepsin-D in methamphetamine-induced apoptotic cell death. Ann NY Acad Sci 1074:234–244
Kim I, Rodriguez-Enriquez S, Lemasters JJ (2007) Selective degradation of mitochondria by mitophagy. Arch Biochem Biophys 462:245–253
Klionsky DJ, Abeliovich H, Agostinis P et al (2008) Guidelines for the use and interpretation of assays for monitoring autophagy in higher eukaryotes. Autophagy 4:151–175
Klionsky DJ, Abdalla FC, Abeliovich H, Abraham RT, Acevedo-Arozena A, Adeli K et al (2012) Guidelines for the use and interpretation of assays for monitoring. Autophagy 8:445–544
Koch OR, Roatta de Conti LL, Bolaños LP, Stoppani AO (1978) Ultrastructural and biochemical aspects of liver mitochondria during recovery from ethanol-induced alterations. Experimental evidence of mitochondrial division. Am J Pathol 90:325–344
Kroemer G, Mariño G, Levine B (2010) Autophagy and the integrated stress response. Mol Cell 40:280–293
Lieber CS, De Carli LM, Sorrell MF (1989) Experimental methods of ethanol administration. Hepatology 10:501–510
Martinet W, De Meyer GR (2009) Autophagy in atherosclerosis: a cell survival and death phenomenon with therapeutic potential. Circ Res 104:304–317
Martinet W, De Meyer GR, Andries L, Herman AG, Kockx MM (2006) In situ detection of starvation-induced autophagy. J Histochem Cytochem 54:85–96
Mitsuhashi S, Hatakeyama H, Karahashi M, Koumura T, Nonaka I, Hayashi YK, Noguchi S, Sher RB, Nakagawa Y, Manfredi G, Goto Y, Cox GA, Nishino I (2011) Muscle choline kinase beta defect causes mitochondrial dysfunction and increased mitophagy. Hum Mol Genet 20:3841–3845
Mizushima N, Yamamoto A, Matsui M, Yoshimori T, Ohsumi Y (2004) In vivo analysis of autophagy in response to nutrient starvation using transgenic mice expressing a fluorescent autophagosome marker. Mol Biol Cell 15:1101–1111
Mizushima N, Yoshimori T, Levine B (2010) Methods in mammalian autophagy research. Cell 140:313–326
Nahdi A, Hammami I, Kouidhi W, Chargui A, Ben Ammar A, Hamdaoui MH, El May A, El May M (2010) Protective effects of crude garlic by reducing iron-mediated oxidative stress, proliferation and autophagy in rats. J Mol Histol 41:233–245
Narendra DP, Youle RJ (2011) Targeting mitochondrial dysfunction: role for PINK1 and Parkin in mitochondrial quality control. Antioxid Redox Signal 14:1929–1938
Nishida Y, Arakawa S, Fujitani K, Yamaguchi H, Mizuta T, Kanaseki T, Komatsu M, Otsu K, Tsujimoto Y, Shimizu S (2009) Discovery of Atg5/Atg7-independent alternative macroautophagy. Nature 461:654–658
Novak I (2012) Mitophagy: a complex mechanism of mitochondrial removal. Antioxid Redox Signal 17:794–802
Obert LA, Sobocinski GP, Bobrowski WF, Metz AL, Rolsma MD, Altrogge DM, Dunstan RW (2007) An immunohistochemical approach to differentiate hepatic lipidosis from hepatic phospholipidosis in rats. Toxicol Pathol 35:728–734
Osna NA, Thomes PG, Donohue TM Jr (2011) Involvement of autophagy in alcoholic liver injury and hepatitis C pathogenesis. World J Gastroenterol 17:2507–2514
Pan T, Rawal P, Wu Y, Xie W, Jankovic J, Le W (2009) Rapamycin protects against rotenone-induced apoptosis through autophagy induction. Neuroscience 164:541–551
Puyal J, Vaslin A, Mottier V, Clarke PG (2009) Postischemic treatment of neonatal cerebral ischemia should target autophagy. Ann Neurol 66:378–389
Rodriguez-Navarro JA, Cuervo AM (2010) Autophagy and lipids: tightening the knot. Semin Immunopathol 32:343–353
Sansanwal P, Yen B, Gahl WA, Ma Y, Ying L, Wong LJ, Sarwal MM (2010) Mitochondrial autophagy promotes cellular injury in nephropathic cystinosis. J Am Soc Nephrol 21:272–283
Shintaku M (2011) Immunohistochemical localization of autophagosomal membrane-associated protein LC3 in granular cell tumor and schwannoma. Virchows Arch. doi:10.1007/s00428-011-1104-z
Singh R, Cuervo AM (2012) Lipophagy: connecting autophagy and lipid metabolism. Int J Cell Biol 2012:282041. doi:10.1155/2012/282041
Singh R, Kaushik S, Wang Y, Xiang Y, Novak I, Komatsu M, Tanaka K, Cuervo AM, Czaja MJ (2009) Autophagy regulates lipid metabolism. Nature 458:1131–1135
Teckman JH, An JK, Blomenkamp K, Schmidt B, Perlmutter D (2004) Mitochondrial autophagy and injury in the liver in alpha 1-antitrypsin deficiency. Am J Physiol Gastrointest Liver Physiol 286:G851–G862
Thomes P, Trambly CS, Osna NA, Clemens DL, Thiele GM, Duryee MJ, Fox HS, Haorah J (2010) Proteasome activity and autophagy in liver are reciprocally affected after ethanol exposure. Hepatology 52:A615
Thomes PG, Trambly CS, Thiele GM, Duryee MJ, Fox HS, Haorah J, Donohue TM Jr (2012) Proteasome activity and autophagosome content in liver are reciprocally regulated by ethanol treatment. Biochem Biophys Res Commun 417:262–267
Vives-Bauza C, Zhou C, Huang Y, Cui M, de Vries RL, Kim J, May J, Tocilescu MA, Liu W, Ko HS, Magrané J, Moore DJ, Dawson VL, Grailhe R, Dawson TM, Li C, Tieu K, Przedborski S (2010) PINK1-dependent recruitment of Parkin to mitochondria in mitophagy. Proc Natl Acad Sci 107:378–383
Walther TC, Farese RV Jr (2009) The life of lipid droplets. Biochim Biophys Acta 1791(6):459–466
Wang Y, Nartiss Y, Steipe B, McQuibban GA, Kim PK (2012) ROS-induced mitochondrial depolarization initiates PARK2/PARKIN-dependent mitochondrial degradation by autophagy. Autophagy 8:1462–1476
Watanabe E, Muenzer JT, Hawkins WG, Davis CG, Dixon DJ, McDunn JE, Brackett DJ, Lerner MR, Swanson PE, Hotchkiss RS (2009) Sepsis induces extensive autophagic vacuolization in hepatocytes: a clinical and laboratory-based study. Lab Invest 89:549–561
Yan M, Zhu P, Liu HM, Zhang HT, Liu L (2007) Ethanol induced mitochondria injury and permeability transition pore opening: role of mitochondria in alcoholic liver disease. World J Gastroenterol 13:2352–2356
Yang DS, Lee JH, Nixon RA (2009) Monitoring autophagy in Alzheimer’s disease and related neurodegenerative diseases. Methods Enzymol 453:111–114
Yerian L (2011) Histopathological evaluation of fatty and alcoholic liver diseases. J Dig Dis. 12:17–24
Youle RJ, Narendra DP (2011) Mechanisms of mitophagy. Nat Rev Mol Cell Biol 12:9–14
Zhong W, Zhao Y, Tang Y, Wei X, Shi X, Sun W, Sun X, Yin X, Sun X, Kim S, McClain CJ, Zhang X, Zhou Z (2012) Chronic alcohol exposure stimulates adipose tissue lipolysis in mice: role of reverse triglyceride transport in the pathogenesis of alcoholic steatosis. Am J Pathol 180:998–1007
Zhou C, Huang Y, Shao Y, May J, Prou D, Perier C, Dauer W, Schon EA, Przedborski S (2008) The kinase domain of mitochondrial PINK1 faces the cytoplasm. Proc Natl Acad Sci USA 105(33):12022–12027
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Below is the link to the electronic supplementary material.
10735_2013_9483_MOESM1_ESM.pptx
Supplementary Fig. 1 Immunohistochemistry for LC3 in control and ETR hepatocytes using HRP-DAB reaction. Arrows indicate LC3 puncta (brown dots) (PPTX 353 kb)
Rights and permissions
About this article
Cite this article
Eid, N., Ito, Y., Maemura, K. et al. Elevated autophagic sequestration of mitochondria and lipid droplets in steatotic hepatocytes of chronic ethanol-treated rats: an immunohistochemical and electron microscopic study. J Mol Hist 44, 311–326 (2013). https://doi.org/10.1007/s10735-013-9483-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10735-013-9483-x