Table 2.

Summary of evidence highlighting the role of dopamine in the pathogenesis of diabetes-related chronic complications and implication for therapy.

Diabetes-Related Traditional Chronic Complication	Role of Dopamine	Effect	Rationale for Treatment (Dopamine Agonists or Levodopa)
Retinopathy [45,46,47,48,49,50,51,52,53,54,55]	Impaired intraretinal metabolism (deficiency)	Defective photoreceptor adaptation to light	Yes
Chronic renal disease [56,57,58,59,60]	Impaired renal metabolism (glomerular filtration-depended reduction)	Dysregulation in water and natrium resorption; promotion of glomerular hyperfiltration; micro- and macroalbuminuria	Scanty evidence or negative results
Neuropathy [64,65,66]	Defective axonal transport; impaired metabolism (accumulation due to inadequate conversion to noradrenaline?)	Implication for painful neuropathy	No (dopamine antagonists)
Stroke [72,73,74,75,76,77,78]	Impaired cerebral metabolism (deficiency)	Loss of motivation, motor impairment, and pathogenic role in post-stroke neuropsychiatric disorder	Scanty evidence or negative results
Cardiovascular diseases [61,62,63,64,65,66,67,68,69,70]	Impaired cardiac metabolism (accumulation due to inadequate conversion to noradrenaline?); striatal deficiency	Increased risk of heart failure, impaired coronary vasodilatation, cardiac autonomic neuropathy	Scanty evidence or negative results

Table 2 summarizes the leading evidence indicating the role of dopamine in the pathophysiology of traditional diabetes-related chronic complications.