NEUROTROPHINS AND OTHER GROWTH-FACTORS IN DIABETIC NEUROPATHY

There is enthusiasm for the application of knowledge concerning neurot rophins and other growth factors to human neurologic disease. New neur otrophins and other growth factors or inflammatory mediators that infl uence neurons and axons have been recently identified, Diabetic neurop athy may be an ideal testing ground for these substances because speci fic neurotrophins and growth factors could theoretically prevent loss of diabetic dorsal root ganglion (DRG) cells or enhance regeneration o f diabetic nerves, Several of the neurotrophins support DRG cells in c ulture or prevent their loss during neonatal development, and a few he lp prevent retrograde loss of adult DRG cells after axotomy, Early Pha se I trials suggest that nerve growth factor, brain-derived neurotroph ic factor, and neurotrophin-3 are reasonably safe agents as administer ed in short-term trials to humans, but there are lingering experimenta l doubts, For example, it has not been established whether DRG cells a re targeted by diabetes, Additional work suggests that simultaneous an d sequential cocktails of trophins are required to support and rescue neurons and that the use of single agents may not be sufficient, Final ly, it is uncertain whether trophins might act as a general tonic for DRG cells to prevent diabetes-related injury or whether they are actua lly deficient in human diabetic patients.