[Repercussions of chromium picolinate in the protein metabolism based on the age]. / Repercusiones del picolinato de cromo en el metabolismo proteico en función de la edad.

ANTECEDENTS: Commercialized like dietetic supplement, chromium picolinate has been promoted to favour the increase of muscle mass and the loss of weight, due to its' effect on the action of insulin. OBJECTIVE: To evaluate the effect of supplementation of the diet with chromium (500 microg/kg) in the form of chromium picolinate (CrPic) (12 days) on growth and protein turnover in rats at different growth stages (infantile and puberal). RESULTS AND DISCUSSION: No significant effect of CrPic on bodyweight gain, feed intake and feed conversion rate was observed at any of the stages of development studied. CrPic seems to increase the muscle mass, either by stimulating protein anabolism due to the involution of the insulin by chromium, or by reducing protein catabolism. CONCLUSIONS: Since the use of chromium picolinate could jeopardize the correct renal function and its' beneficial effects are not evident, it should always be consumed with caution.

Peligros y beneficios potenciales de la suplementación con picolinato de cromo a ratas en edad puberal: efecto sobre el crecimiento y metabolismo proteico / Dangers and potential benefits of the suplementation with chromium picolinate to rats in puberal age: effect on the growth and protein metabolism

El cromo, un popular pero controvertido micronutriente, puede incrementar el músculo esquelético cuando se administra en forma de suplemento, presumiblemente debido a su acción sobre la insulina. Este estudio se ha realizado con el fin de evaluar los efectos de tres niveles diferentes de cromo dietético (100, 200 y 500 µg/Kg) en forma de picolinato de cromo (Pic-Cr) sobre el crecimiento y utilización proteica de ratas en edad puberal, durante doce días. La suplementación de la dieta de estos animales no ejerce un efecto significativo sobre el crecimiento, ingesta de alimento, aprovechamiento de alimento y utilización de nutrientes, especialmente de proteínas. El efecto del PicCr sobre la masa corporal, además de no ser significativo, sería totalmente marginal y atribuible, más que a su acción sobre la activación de la insulina, a su capacidad para disminuir el catabolismo proteico. El consumo de este compuesto, además, podría comprometer el buen funcionamiento renal, por lo que debería realizarse con mucha precaución (AU)

Cerebrospinal fluid levels of selenium in patients with Alzheimer's disease.

We compared CSF and serum selenium levels, measured by atomic absorption spectrophotometry, in 27 patients with Alzheimer's disease (AD) (13 females, 14 males, mean +/- SD age 73.6 +/- 7.4 years) without major clinical signs of undernutrition, and 34 matched controls (18 females, 16 males, mean +/- SD age 70.7 +/- 7.8 years). CSF and serum selenium levels did not differ significantly between AD-patient (11.4 +/- 7.8 ng/ml and 28.5 +/- 13.0 ng/ml, respectively) and control groups (13.3 +/- 7.0 ng/ml and 22.5 +/- 17.5 ng/ml). These values were not correlated with age, age at onset, duration of the disease, and scores of the MiniMental State Examination in the AD group. Weight and body mass index were significantly lower in AD patients than in controls. These results suggest that CSF selenium concentrations are apparently unrelated with the reported oxidative stress processes in patients with AD.

Cerebrospinal fluid selenium and chromium levels in patients with Parkinson's disease.

We compared CSF and serum levels of selenium and chromium, measured by atomic absorption spectrophotometry, in 28 patients with Parkinson's disease (PD) and 43 matched controls. The CSF and serum levels of these trace metals did not differ significantly between PD patients and controls. CSF selenium and chromium levels were not correlated with age, age at onset, duration of the disease, scores of the Unified Parkinson Disease Rating Scale of the Hoehn and Yahr staging in the PD group. Although antiparkinsonian therapy did not influence significantly the CSF levels of selenium, PD patients not treated with levodopa had significantly higher CSF selenium levels than controls (p < 0.01). It is possible that increased CSF selenium levels could indicate an attempt of protection against oxidative stress. The normality of CSF and serum chromium levels suggest that these values are not related with the risk for PD.

Effects of arsenic (V)-chromium (III) interaction on plasma glucose and cholesterol levels in growing rats.

Recent studies have demonstrated interaction between arsenic (As) and chromium (Cr) affecting absorption and/or protein catabolism. In the present study the possible effects of As(V)/Cr(III) interaction on growth rate, organ weight, and the two main organic functions of Cr, i.e., regulation of plasma glucose levels and total plasma cholesterol levels, was examined in weaned male Wistar rats. The diet of 20 rats was supplemented with 5 micrograms of As(V) and/or Cr(III) per gram of food for 10 weeks. As/Cr interaction did not significantly affect growth rates on organ weight:body weight ratios but did decrease total plasma cholesterol levels, though the decrease was not as pronounced as in the group supplemented with Cr alone (p < 0.1). Since supplementation with As(V) produced the opposite effect (96.83 vs. 47.27) (p < 0.01), the combined use of As and Cr may prove beneficial in cases of chronic As(V) intoxication. Supplementation treatment with As(V) and Cr(III) combined had no significant effect on glucose levels, because though As(V) affects Cr tissue levels and thus alters the effect of Cr on plasma cholesterol levels, individual effects of As(V) and Cr(III) are similar, and hence basal glucose levels are unaffected.