Predavanje Janeza Štuparja, Matjaža Vrtovca, Francija Dolinška

The essentiality of Cr in humans has been demonstrated by a patient on a long term total parenteral nutrition who's signs and symptoms of severe glucose intolerance were reversed by supplementation with Cr. Cr in its bioactive form synthesized in the organism is involved in carbohydrate and lipid metabolism by activation of insulin.

Incidence of impaired glucose tolerance and type 2 diabetes is growing rapidly among elderly population particularly in civilized countries. It has been postulated that compromised Cr body stores due to sub optimal dietary intake and change in live style are the main reasons. In order to assess Cr status of a human subject measurement of various biochemical parameters such as blood-Cr, sweat-Cr and hair-Cr were proposed. There has been a lot of debate and controversial opinion about which of these parameters better reflect Cr body burden.

In this lecture hair analysis is critically reviewed and potentialities of hair-Cr determination in assessing of Cr nutriture and likelihood of development of glucose intolerance are investigated.

Longitudinal hair-Cr (H-Cr) profiles in a group of healthy elderly (control) subjects (N = 49, age 59 ±10y) and type 2 diabetic patients (N = 59, age 62 ± 9y) matched by gender were measured by solid sampling atomic absorption spectrometry (ETAAS). From the data the percent variation of Cr content along the hair length, H-Cr average (H-Crav.) and H-Cr proximal (H-Crpr.) relating to the Cr content of the whole and the proximal 3mm hair length, were deduced. Differences in these parameters between healthy population and type 2 diabetes were evaluated. Diabetics in contrast to the healthy population displayed substantially larger variation of Cr content along the hair length. This fairly specific feature may be explained by the large variations of circulating insulin and fasting plasma glucose of diabetics in comparison to healthy population. Additionally, relationship between hair-Cr and plasma glucose, plasma insulin and HbA1cwas investigated. Relatively strong association was found in healthy population but not in diabetic group. This suggests that glucose intolerance significantly disturbs Cr metabolism. H-Crav. values, which are generally reported in the literature, cannot be used as an accurate predictor of Cr status.

• Janez Stupar, School of Environmental Sciences Polytechnic, Nova Gorica, Vipavska 13, 5001 Nova Gorica, Slovenia, E-mail: janez.stupar@siol.net

• Matjaž Vrtovec, Dept. Of Endocrinology and Metabolism, University Medical Centre, 1000 Ljubljana, Slovenia

• Franci Dolinšek, Centre for Forensic Research, Ministry of the Interior, 1000 Ljubljana, Slovenia