Cytokines are low molecular weight substances, mediating intra and intercellular communications. They are produced by several cell types, including the liver
with a special focus on Kupffer cells. In the liver, pathological stimuli induce cytokines
release and are responsible for cell lesions, destruction, necrosis, apoptosis and
regeneration. In alcoholic liver disease (ALD) inflammatory cytokines such as
interleukin-8 (IL-8) tumor necrosis factor (TNF), interleukin-1 (IL-1), and interleukin-6
(IL-6) as an acute phase-cytokine are involved in the liver injury. Another proinflammatory interleukin is interleukin-12 (IL-12), which seems to be related to
chronic alcoholism. Transforming growth factor β (TGF-β) has the most important
fibrogenic properties in the liver and it is also involved in regulating apoptosis along
with tumor necrosis factor. Several types of cytokines are described to induce antiinflammatory effects on the liver with chronic alcoholic exposure: Kupffer cells
produce the hepatoprotective cytokine IL-6 and the anti-inflammatory cytokine
interleukin- 10 (IL-10) during liver injury induced by alcohol. IL-6 acts in a protective
manner via the activation of transcription 3 and induction of hepatoprotective genes in
hepatocytes. IL-10 inhibits alcoholic liver damage in Kupffer cells/macrophages.
Interleukin-22 (IL-22) is another important hepatoprotective cytokine against acute and
chronic alcoholic liver injury. Adipocytokine adiponectin decreases hepatic insulin
resistance and attenuates liver inflammation and fibrosis. Thus findings in the complex
“puzzle” of ALD could launch the research for new therapeutic perspectives.
Keywords: Adiponectin, Alcoholic liver disease, Cytokines, Fibrosis, Inflammation, Interleukins.
