Chromium Supplementation in Human Health, Metabolic Syndrome, and Diabetes
Chromium Supplementation in Human Health, Metabolic Syndrome, and Diabetes
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DOI：
10.1515/9783110527872-009
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发表时间：
2019-01-01
期刊：
影响因子：
--
通讯作者：
Maret, Wolfgang
中科院分区：
文献类型：
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作者：
Maret, Wolfgang
经过40年的重要工作，人们普遍认为，三价铬，即三价铬，是人类必需的微量营养素。这一观点在世纪之交开始受到挑战。一些研究人员认为，它对葡萄糖和脂肪代谢的影响反映了一种药理作用，而不是一种营养作用模式，而另一些人则对补充铬的毒性和安全性表示担忧。理解这些猜想需要反思“基本”的不同定义，以及对该领域发展的看法，该领域本身就是科学史和教育的一个引人注目的片段。讨论的中心是我们未能确定生物铬络合物的分子结构和特定的作用部位。相反，许多不同类型的铬(III)络合物，特别是吡啶甲酸铬，以及那些具有烟酸盐、丙酸、组氨酸、氯化物和其他配体的铬(III)络合物，都具有不同的化学性质和生物活性，正被用于实验室研究和补充。由于缺乏对生物配体赋予铬的代谢转化和特定化学性质的了解，许多这些研究，特别是那些体外研究，对于了解铬的生物学功能的价值有限。人类是否存在铬缺乏症，以及谁会受到影响，目前还没有明确的定义。有证据表明，铬补充剂在改善代谢综合征和一些2型糖尿病患者的病情方面有效，但对健康个体的身体成分没有影响。铬存在于人体组织和我们的食物中，铬(III)化合物存在于(全)肠外营养中，由运动员和健美运动员作为补充剂服用，是普通人群食用的维生素丸的成分，并用于动物营养。另一个有争议的问题是，铬(III)络合物是否安全，因为六价铬铬(VI)(铬酸盐)是遗传毒性的，而且对人类来说是一种I类致癌物质，有足够的吸入和肺癌证据。为了人类健康的利益，仍然需要一个平衡的观点和知情和强有力的实验，以确定参与铬(III)代谢的特定生物分子，特定作用部位的生物铬(III)络合物的活性，以及可能导致长期毒性的补充铬(III)的量。
After 40 years of significant work, it was generally accepted that chromium in its trivalent valence state, Cr(III), is an essential micronutrient for humans. This view began to be challenged around the turn of the millennium. Some investigators argue that its effects on glucose and lipid metabolism reflect a pharmacological rather than a nutritional mode of action while yet others express concern about the toxicity and safety of supplemental chromium. Understanding the conjectures requires a reflection on the different definitions of "essential" and a perspective on the development of the field, which in itself is a remarkable snippet of science history and education. At the center of the discussion is our failure to have established a molecular structure and a specific site of action of a biological chromium complex. Instead, many different types of Cr(III) complexes, in particular chromium picolinate, but also those with nicotinate, propionate, histidinate, chloride, and other ligands, all with different chemical properties and biological activities, are being used in laboratory investigations and supplementation. Without knowledge of the metabolic transformations and the specific chemical properties that biological ligands impart on chromium, many of these investigations, in particular those ex vivo, have limited value for understanding chromium's biological function. Whether a chromium deficiency exists in humans and who is affected is poorly defined. There is evidence for the efficacy of chromium supplements in improving conditions in metabolic syndrome and in some diabetes Type 2 patients, but there are no effects on body composition in healthy individuals. Chromium is present in human tissues and in our food and Cr(III) compounds are given in (total) parenteral nutrition, taken as a supplement by athletes and bodybuilders, are ingredients of vitamin pills consumed by the general population, and are employed in animal nutrition. Another contentious issue is whether Cr(III) complexes are safe, as chromium in its hexavalent state, Cr(VI) (chromate), is genotoxic and a group I carcinogen for humans with sufficient evidence for inhalation and lung cancer. For the benefit of human health, there is a continuing need for a balanced view and informed and robust experiments to determine the specific biological molecules that are involved in the metabolism of Cr(III), the activity of biological Cr(III) complexes at specific sites of action, and the amount of supplemental Cr(III) that potentially causes long-term toxicity.