骨血管轴:慢性病相关血管化的关键参与者

Bones are dynamic organs that require a rich supply of oxygen and nutrients. Around 5% to 10% of the cardiac output supplies blood to the bones. A typical long bone has three main sources: the nutrient artery, the metaphyseal and epiphyseal arteries, and the periosteal arteries.
Nutrient Artery
The nutrient artery is the main blood vessel that enters the diaphysis via the nutrient foramen. While most long bones have only one nutrient foramen, large bones, such as the femur, may have two. This...

Aging and its effect on bone remodeling is the most common cause of bone disorders. In young and healthy people, bone deposition and resorption happen at an equal rate to maintain optimal bone health.
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...

Osteoclasts are cells responsible for bone resorption and remodeling. They originate from hematopoietic progenitor cells present in the bone marrow. Numerous progenitor cells fuse to form multinucleated cells, each with 10-20 nuclei. A single osteoclast has a diameter of 150 to 200 µM. These cells have ruffled borders that break down the underlying bone tissue and release minerals such as calcium into the blood in bone resorption. Osteoclasts cling to bones with their ruffled edges during...

Bone contains a relatively small number of cells entrenched in a matrix of collagen fibers that provide an adherent surface for inorganic salt crystals. Both components of the matrix, organic and inorganic, contribute to the unusual properties of bone. Without collagen, bones would be brittle and shatter easily. Without mineral crystals, bones would flex and provide little support. This can be observed by an experiment: when the minerals of a bone are dissolved by soaking the bone in...