Serum Hemorphin-7 Levels Are Decreased

Hemorphins are small peptides generated by enzymatic cleav-age from β-globin chains during catabolism of human hemo-globin. These peptides exhibit biological activities that interfere with the endorphin system, the inflammatory response, blood-pressure control, and cognitive function (1).VV-hemorphin-7 and LVV-hemorphin-7 globin fragments peptides have been described to exert a hypotensive effect by specifically inhibiting the angiotensin-converting enzyme (2,3) and mimicking angiotensin IV cellular actions (4). We have earlier shown decreased serum VV-hemorphin-7 like immu-noreactivity (VVH7-i.r.) levels in different type 1 and type 2 diabetic populations (5). Furthermore, a negative correlation between serum VVH7-i.r. level and diastolic blood pressure (DBP) has been found in non-albuminuric patients with type 1 diabetes, suggesting that decreased VVH7-i.r. may influence vascular and renal complications in diabetes (5).Unfortunately, the mechanisms involved in the reduction of VVH7-i.r. concentration in diabetes remain unexplained. Some hypotheses, such as interference of the glycation phe-nomenon at the cleavage site of the hemoglobin β chain (6), or dysfunction of enzymes involved in hemorphin production (cathepsin D) or catabolism (dipeptidyl peptidase IV and angi-otensin-converting enzyme) have been ruled out (5).Because obesity and type 2 diabetes share insulin resistance, high glomerular-filtration rate (GFR), microinflammation, and high cardiovascular risk, we investigated whether obesity could also exhibit such hemorphin abnormalities.