Severe burn injury triggers the body＇s nonspecific adaptive responses to acute insult, including the systemic inflammatory and stress responses, as well as the sympathetic response to immobilization. These responses ...Severe burn injury triggers the body＇s nonspecific adaptive responses to acute insult, including the systemic inflammatory and stress responses, as well as the sympathetic response to immobilization. These responses trigger inflammatory bone resorption followed by glucocorticoid-induced apoptosis of osteoblasts and probably osteocytes. Because these patients are catabolic, they suffer concomitant muscle wasting and negative nitrogen balance. The use of anabolic agents such as recombinant human growth hormone and oxandrolone results in improved bone mineral content and muscle strength after approximately I year. Use of bisphosphonates within the first 10 days of a severe burn completely blocks the resorptive bone loss and has the added advantage of appearing to preserve muscle protein from excessive breakdown. The mechanism for the protective effect on muscle is not currently known. However, if the effect of bisphosphonates on muscle can be confirmed, it raises the possibility that bone communicates with muscle.展开更多
While insulin-like growth factorⅠis a well-known anabolic agent in bone evidence is beginning to accumulate that its homologue,insulin,also has some anabolic properties for bone.There is specific evidence that insuli...While insulin-like growth factorⅠis a well-known anabolic agent in bone evidence is beginning to accumulate that its homologue,insulin,also has some anabolic properties for bone.There is specific evidence that insulin may work to stimulate osteoblast differentiation,which in turn would enhance production of osteocalcin,the osteoblast-produced peptide that can stimulate pancreaticβcell proliferation and skeletal muscle insulin sensitivity.It is uncertain whether insulin stimulates bone directly or indirectly by increasing muscle work and therefore skeletal loading.We raise the question of the sequence of events that occurs with insulin resistance,such as type 2 diabetes.Evidence to date suggests that these patients have lower serum concentrations of osteocalcin,perhaps reduced skeletal loading,and reduced bone strength as evidenced by microindentation studies.展开更多
基金partial support from P50 GM60338 from the National Institutes of Health and several grants from Shriners Hospitals for Children
文摘Severe burn injury triggers the body＇s nonspecific adaptive responses to acute insult, including the systemic inflammatory and stress responses, as well as the sympathetic response to immobilization. These responses trigger inflammatory bone resorption followed by glucocorticoid-induced apoptosis of osteoblasts and probably osteocytes. Because these patients are catabolic, they suffer concomitant muscle wasting and negative nitrogen balance. The use of anabolic agents such as recombinant human growth hormone and oxandrolone results in improved bone mineral content and muscle strength after approximately I year. Use of bisphosphonates within the first 10 days of a severe burn completely blocks the resorptive bone loss and has the added advantage of appearing to preserve muscle protein from excessive breakdown. The mechanism for the protective effect on muscle is not currently known. However, if the effect of bisphosphonates on muscle can be confirmed, it raises the possibility that bone communicates with muscle.
文摘While insulin-like growth factorⅠis a well-known anabolic agent in bone evidence is beginning to accumulate that its homologue,insulin,also has some anabolic properties for bone.There is specific evidence that insulin may work to stimulate osteoblast differentiation,which in turn would enhance production of osteocalcin,the osteoblast-produced peptide that can stimulate pancreaticβcell proliferation and skeletal muscle insulin sensitivity.It is uncertain whether insulin stimulates bone directly or indirectly by increasing muscle work and therefore skeletal loading.We raise the question of the sequence of events that occurs with insulin resistance,such as type 2 diabetes.Evidence to date suggests that these patients have lower serum concentrations of osteocalcin,perhaps reduced skeletal loading,and reduced bone strength as evidenced by microindentation studies.
