{"id":2167942,"date":"2019-09-24T13:23:35","date_gmt":"2019-09-24T17:23:35","guid":{"rendered":"https:\/\/www.futurity.org\/?p=2167942"},"modified":"2021-06-17T14:30:50","modified_gmt":"2021-06-17T18:30:50","slug":"apoe-protein-broken-bones-older-adults-2167942-2","status":"publish","type":"post","link":"https:\/\/www.futurity.org\/apoe-protein-broken-bones-older-adults-2167942-2\/","title":{"rendered":"This protein slows the healing of broken bones"},"content":{"rendered":"
A protein more prevalent in older people interferes with bone healing, report researchers.<\/p>\n
Broken bones are a bigger deal the older you are: even after they’ve healed, the bones of older people are weaker and more likely to re-fracture. And since more than 6 million Americans break a bone each year, figuring out how to help people heal better would make a big difference, researchers say.<\/p>\n
“When we decreased the protein level, aging was reversed,” says Gurpreet Baht, an assistant professor in the Duke University orthopaedic surgery department and senior author of the paper in JCI Insights<\/a><\/em>. “Not only was there more bone and healing happened faster, but it was also structurally more sound.”<\/p>\n Baht’s team confirmed that older people have more Apolipoprotein E, (ApoE) than younger people. Researchers have also implicated ApoE<\/a> in Alzheimer’s and heart disease.<\/p>\n The researchers discovered that that 75-85 year olds have twice as much ApoE in their bloodstreams as 35-45 year olds, then found the same was true for 24-month-old mice versus 4-month-old mice, which approximate the same human age ranges.<\/p>\n Next, they wanted to figure out if and how ApoE affects the multi-step process of bone healing. When you break a bone, your body sends signals through the bloodstream to recruit cells to fix it. Some of those recruits, specifically skeletal stem cells, build up cartilage as a temporary scaffolding to hold the fracture together.<\/p>\n In the next step, more recruited cells mature into osteoblasts, bone-building cells, which lay strong, dense bone cells on top of the cartilage scaffolding. Finally, a different kind of cell eats up the cartilage scaffolds and osteoblasts fill those holes with bone.<\/p>\n “Over time, this cartilage will continue to be resorbed and osteoblasts will continue to deposit new bone,” Baht explains. “After a few months of your arm or leg healing, there will be almost no cartilage anymore. And if you were to look at it five years out, there’d be no sign of an injury anymore.”<\/p>\nBone-building cells<\/h3>\n