RESUMO
The concentrations of essential metal ions in various compartments of the human body are accurately regulated (homeostasis). Irregularities in the accumulation or depletion of the trace elements may lead to well characterized diseases. This review covers the metabolism of zinc regulations by which the intracellular and extracellular levels are kept in physiological range, biological functions, as well as pathological states that develop in its altered metabolism. The focus is on the molecular mechanisms of zinc ion traffic between compartments of the body and cells and their sequestration, gene regulations that regulate the ion fluxes via biological membranes and their storage, zinc-mediated cell and tissue damages, and development of symptoms in zinc deficiency is also discussed.
Assuntos
Oligoelementos/metabolismo , Zinco/metabolismo , Anemia Hipocrômica/induzido quimicamente , Suplementos Nutricionais , Homeostase , Humanos , Absorção Intestinal , Metalotioneína/metabolismo , Transdução de Sinais , Oligoelementos/administração & dosagem , Oligoelementos/efeitos adversos , Zinco/administração & dosagem , Zinco/efeitos adversos , Zinco/deficiência , Zinco/fisiologiaRESUMO
The authors summarize the role of essential macro metal elements (Na, K, Ca, Mg) in human body: their homeostasis, absorption, transport, storage and excretion. Metabolism of macro-elements, daily requirements, cause of metal deficiencies and diseases caused by deficiencies are also discussed. Messenger and prooxidant effect of Ca2+-ions, indirect antioxidant effect of Mg2+-ions and the adjuvant application of magnesium are also reviewed.
Assuntos
Cálcio da Dieta/farmacocinética , Deficiências Nutricionais/metabolismo , Canais Iônicos/metabolismo , Compostos de Magnésio/farmacocinética , Potássio na Dieta/farmacocinética , Sódio na Dieta/farmacocinética , Antioxidantes/farmacocinética , Transporte Biológico Ativo , Cálcio/deficiência , Canais de Cálcio/metabolismo , Cálcio da Dieta/administração & dosagem , Cálcio da Dieta/metabolismo , Deficiências Nutricionais/diagnóstico , Humanos , Absorção Intestinal , Transporte de Íons/fisiologia , Compostos de Magnésio/administração & dosagem , Compostos de Magnésio/metabolismo , Deficiência de Magnésio/metabolismo , Oxidantes/farmacocinética , Canais de Potássio/metabolismo , Deficiência de Potássio/metabolismo , Potássio na Dieta/administração & dosagem , Potássio na Dieta/metabolismo , Sódio/deficiência , Canais de Sódio/metabolismo , Sódio na Dieta/administração & dosagem , Sódio na Dieta/metabolismoRESUMO
The role of essential nutrient metal ions (Mg, Fe, Cu, Zn, Mn and Co) often deficient in our foodstuffs, although vitally essential in the function of the human organism as well as the different reasons for these deficiencies both in foods and in the human body have been studied. The most frequent nutritional disease is iron deficient anaemia. Inorganic salts, artificial synthetic monomer organic metal complexes of high stability or organic polymer complexes of high molecular mass are unsatisfactory for supplementation to the human body, owing to poor absorption, low availability and/or harmful side effects. In contrast, we have recently found that mixed metal complexes of oligo/polygalacturonic acids with medium molecular weight prepared from natural pectin of plant origin are efficient for oral supplementation. Sufficient absorption of essential metal ions from metal oligo/polygalacturonate mixed complexes with polynuclear innersphere structure is due to the high ionselectivity and medium stability values. Metal oligo/polygalacturonate mixed complexes contain all deficient essential metal ions in adequate amounts and ratios for higher bioavailability of metal ions and optimal vital function. Therefore, by oral administration of these complexes, metal ion homeostasis and optimal interactions with vitamins and hormones can be ensured. Prelatent or latent macroelement Mg deficiency can often be observed among clinical or ambulance patients. Latent or manifest mesoelement iron deficiency is the most common, however, the occurrence of microelement copper, zinc, manganese and cobalt latent deficiencies is not seldom either. Supplementation studies utilizing essential metal oligo/polygalacturonate complexes led to satisfactory outcome without harmful side effects.
Assuntos
Deficiências Nutricionais/prevenção & controle , Suplementos Nutricionais , Ácidos Hexurônicos/administração & dosagem , Oligoelementos/administração & dosagem , Administração Oral , Anemia Ferropriva/prevenção & controle , Disponibilidade Biológica , Cobalto/administração & dosagem , Cobre/administração & dosagem , Deficiências Nutricionais/etiologia , Deficiências Nutricionais/metabolismo , Humanos , Absorção Intestinal , Ferro/administração & dosagem , Manganês/administração & dosagem , Peso Molecular , Pectinas , Veículos Farmacêuticos , Zinco/administração & dosagemRESUMO
A hyperlipidemic rat model was used to examine the therapeutic effect of Sempervivum tectorum plant extract on the metabolic alterations of Al, As, B, Ba, Cd, Hg, Ni, Pb, and Ti in the liver and bile. Hyperlipidemia was produced by lipogenic diet and alcohol and verified by morphological investigation of the liver with the aid of light and an electron microscope. Element concentration in the liver and bile were determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The concentration values in the liver higher than the detection limit (Al, Ba, Ni, Ti) were unambiguous. Significant differences were found for the four groups at p < 0.05 level (ANOVA). A significant difference was observed between Al and B concentration in the bile fluids of the 4 groups (p < 0.05). The excretion of Al and Ti into the bile fluid increased significantly (p < 0.05). Following the administration of S. tectorum extract to rats with hyperlipidemia, the excretion of Al, B and Ba increased, whereas the excretion of Ti decreased significantly (p < 0.05). The favorable action of the extract (protecting the liver in hyperlipidemic rats) was verified by morphological studies, and its detoxicating property was shown by the elimination of Al, Ba, Ni, and Ti from the liver.
Assuntos
Crassulaceae/química , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Metais/metabolismo , Extratos Vegetais/uso terapêutico , Administração Oral , Animais , Bile/efeitos dos fármacos , Bile/metabolismo , Dieta , Modelos Animais de Doenças , Esquema de Medicação , Hepatócitos/efeitos dos fármacos , Hepatócitos/ultraestrutura , Hiperlipidemias/metabolismo , Hipolipemiantes/administração & dosagem , Hipolipemiantes/farmacocinética , Inativação Metabólica , Fígado/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Metais/análise , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacocinética , Ratos , Ratos Wistar , Suspensão de TratamentoRESUMO
From the rose hip seed, which is generally a waste material, valuable oil can be obtained for medicinal use. Various extraction methods have been compared: traditional solvent extraction with ultrasound-, microwave-, sub- and supercritical fluid extraction (SFE). Unsaturated fatty acid (UFA: oleic-, linoleic- and linolenic acid; 16.25-22.11%, 35.94-54.75%, 20.29-26.48%) and polyunsaturated fatty acid (PUFA:linoleic- and linolenic acid) content were over 90% and 60% in the recovered oils. The oils contained different amounts of metals. The concentration of some metals, particularly iron in microwave oil (27.11 microg g(-1)) is undesirable from the aspect of stability. By traditional solvent extraction, oil was obtained in 4.85 wt/wt%. Subcritical FE appeared to be the best method for the recovery of rose hip oil with highest oil yield (6.68 wt/wt%), carotene- (145.3 microg g(-1)) and linoleic acid content (54.75%). Supercritical FE without organic solvent is suitable for mild recovery of oil. The oil was rich in UFA and PUFA (92.7% and 76.25%) and contained the lowest amount of carotene and pheophytin (36.3 and 45.8 microg g(-1)). Oil yield in most new extraction methods (microwave extraction, super- and subcritical FE) was higher than in the case of traditional Soxhlet extraction. The main benefit of supercritical FE with CO2 is the solvent free oil while in the case of other extractions evaporation of the solvent is needed. Although the content of bioactive compounds in oils was different, all oils may be appropriate for medicinal use.