Osteoporosis and Chronic Liver Disease

The liver is composed of hepatocytes, biliary epithelial cells, Kupffer cells, stellate cells, and hepatic sinusoidal endothelial cells. It also plays an important role in the digestive system and immune system at the same time. The different types of hepatitis, including viral liver diseases, autoimmune liver diseases, and metabolic liver diseases, are all closely related to osteoporosis. People with liver disease have a significantly higher risk of developing osteoporosis than people without hepatitis. Fibrosis is part of the wound-healing response that maintains organs after tissue injury, but excessive fibrosis may also contribute to a variety of human diseases. Hepatic stellate cells are the key to liver fibrosis. The apoptotic hepatocytes stimulate fibrosis in hepatic myofibroblasts, and activated hepatic stellate cells are the main source of myofibroblasts in the liver. Activated hepatic stellate cells possess many voltage-operated calcium channels. Changes in the concentration of calcium ions mediate hepatic stellate cell activation and fibrosis regression. The skeleton is one of the main regulatory mechanisms of calcium ions in the body. Therefore, chronic hepatitis leads to a disturbance of calcium homeostasis in vivo, which may be one of the factors causing bone loss.