The effects of iron deficiency and iron overloading on the mitochondrial enzymes involved in heme synthesis were studied in rat livers. The in vitro activities of several of the enzymes in this pathway were differentially influenced by the in vivo iron status of the animals. delta-Aminolevulinic acid synthase was slightly increased in iron-overloaded animals, but remained normal in iron-deficient animals (0.58 +/- 0.09, 0.91 +/- 0.19 and 0.61 +/- 0.12 nmol delta-aminolevulinic acid/mg per h). Copro- and protoporphyrinogen oxidase activities were increased (20 and 60% above controls) in iron-deficient animals. In contrast, coproporphyrinogen oxidase was decreased by 20%, while protoporphyrinogen oxidase remained unchanged in iron-overloaded rats. These variations of activities were not due to changes in the affinity of these enzymes toward their substrates, as coporphyrinogen had the same Km in each case (0.62 +/- 0.05 M) as did protoporphyrinogen (0.22 +/- 0.035 M). Thus, the Km did not vary with the treatment received by the animals. Ferrochelatase activity was measured by both the pyridine hemochromogen method and by measurement of zinc protoporphyrin with endogenous zinc as substrate. In all cases, ferrochelatase was found to be able to synthesize zinc protoporphyrin with endogenous zinc as substrate. However, the apparent Km of zinc chelatase for protoporphyrin was significantly different in the three groups of animals with Km,appProto, app = 2.4 +/- 0.1 10(-7), 4 +/- 0.3 10(-7) and 9.10 +/- 0.05 10(-7) M in iron-overloaded, control and iron-deficient animals, respectively. When ferrochelatase activity was measured by pyridine hemochromogen, identical results were observed in iron-deficient and control animals but decreased by 45% in iron-overloaded animals. The mitochondrial heme content was also decreased by 40% in iron-overloaded rats but unchanged in either iron-deficient or control rats.
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http://dx.doi.org/10.1016/0167-4838(86)90238-4 | DOI Listing |
Int J Biol Macromol
December 2024
SKL of Marine Food Processing & Safety Control, National Engineering Research Center of Seafood, Collaborative Innovation Center of Seafood Deep Processing, Liaoning Province Key Laboratory for Marine Food Science and Technology, School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China.
In this study, the sodium carboxymethylcellulose (CMC) and xanthan gum (XG) were used to prepare the CXM-Fe hydrogels (CMC: 20 mg/mL, XG: 10 mg/mL) with the addition of Mytilus edulis protein hydrolysate‑iron (MEPH-Fe) complexes. The incorporation of MEPH-Fe complexes formed a denser network structure and the CXM-Fe hydrogels had better pH stability as well as gastrointestinal retention ability. Compared with ferrous sulfate and MEPH-Fe complexes, the CXM-Fe hydrogels at moderate doses (Fe:2 mg/kg) showed impressive recovery effects on iron deficiency anemia (IDA) mice in terms of hematological indices, organ coefficients and iron content, antioxidant capacity, and remarkedly attenuated the infiltration of inflammatory cells as well as the levels of inflammatory factors in iron deficiency-induced colonic inflammation.
View Article and Find Full Text PDFFASEB J
November 2024
Department of Anesthesia, Intensive Care and Pain Medicine, Goethe University Frankfurt, Frankfurt, Germany.
Osteopenia is frequently observed in patients with iron overload, especially in those with HFE-dependent hereditary hemochromatosis (HH). Interestingly, not all mouse models of HH show bone loss, suggesting that iron overload alone may not suffice to induce bone loss. In this study, the bone phenotypes of Hjv and hepatocyte-specific Alk2- and Alk3-deficient mice as additional mouse models of HH were investigated to further clarify, how high iron levels lead to bone loss and which signaling mechanisms are operational.
View Article and Find Full Text PDFTalanta
February 2025
Department of Trace Analysis, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 8, 61-614, Poznań, Poland. Electronic address:
This study investigates the influence of multistrain probiotics and iron supplementation on the distribution and interaction of trace elements in the kidneys of Wistar rats using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) bioimaging. Forty 6-week-old female Wistar rats were divided into five groups, each fed an AIN-93 M diet with varying additions or deficiencies of iron and probiotics, which included a control, an iron-deficient diet, an iron-deficient diet with probiotics, an iron-deficient diet with iron supplementation, and an iron-deficient diet with both probiotics and iron supplementation. The obtained two-dimensional maps of the distribution of elements reveal distinct locations of Cu, Fe, Mn, and Zn in specific tissues of rat kidneys.
View Article and Find Full Text PDFNutrition
January 2025
Institute of Human Nutrition and Dietetics, Poznań University of Life Sciences, Poznań, Poland.
Microbiologyopen
October 2024
Department of Food Sciences, Food Microbiology, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Liege, Belgium.
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