Csontfelszívás

Csontfelszívás, known in English as bone resorption, is a natural physiological process where bone tissue is broken down and its minerals are released into the bloodstream. This process is carried out by specialized cells called osteoclasts, which are derived from hematopoietic stem cells. Osteoclasts attach to the bone surface, secrete enzymes and acids that dissolve the bone matrix, and then absorb the breakdown products.

Bone resorption is a vital component of bone remodeling, a continuous cycle of bone formation (by osteoblasts) and resorption. This remodeling allows the skeleton to adapt to mechanical stress, repair microdamage, and maintain mineral homeostasis, particularly calcium and phosphate levels in the blood. When calcium levels drop, bone resorption is stimulated to release calcium. Conversely, when calcium levels are high, resorption is inhibited.

While a normal part of life, excessive or unbalanced bone resorption can lead to various bone diseases. Conditions such as osteoporosis are characterized by a net loss of bone mass due to resorption outpacing formation, making bones fragile and prone to fractures. Other conditions like Paget's disease and certain types of bone cancer also involve abnormal bone resorption. Understanding the mechanisms of Csontfelszívás is crucial for developing treatments for these debilitating conditions.