Редактирование: ALAS1 (раздел)

==Publications==

{{medline-entry
|title=Heterozygous disruption of [[ALAS1]] in mice causes an accelerated age-dependent reduction in free heme, but not total heme, in skeletal muscle and liver.
|pubmed-url=https://pubmed.ncbi.nlm.nih.gov/33307066
|abstract=5-Aminolevulinic acid (ALA) is the rate-limiting intermediate in heme biosynthesis in vertebrate species; a reaction catalyzed by the mitochondrial ALA synthase 1 ([[ALAS1]]) enzyme. Previously we reported that knockdown of the ubiquitously expressed [[ALAS1]] gene in mice disrupts normal glucose metabolism, attenuates mitochondrial function and results in a prediabetic like phenotype when animals pass 20-weeks of age (Saitoh et al., 2018). Contrary to our expectations, the cytosolic and mitochondrial heme content of [[ALAS1]] heterozygous (A1 /-) mice were similar to WT animals. Therefore, we speculated that regulatory "free heme" may be reduced in an age dependent manner in A1 ± mice, but not total heme. Here, we examine free and total heme from the skeletal muscle and liver of WT and A1 ± mice using a modified acetone extraction method and examine the effects of aging on free heme by comparing the amounts at 8-12 weeks and 30-36 weeks of age, in addition to the mRNA abundance of [[ALAS1]]. We found an age-dependent reduction in free heme in the skeletal muscle and liver of A1 ± mice, while WT mice showed only a slight decrease in the liver. Total heme levels showed no significant difference between young and aged WT and A1 ± mice. [[ALAS1]] mRNA levels showed an age-dependent reduction similar to that of free heme levels, indicating that [[ALAS1]] mRNA expression levels are a major determinant for free heme levels. The free heme pools in skeletal muscle tissue were almost 2-fold larger than that of liver tissue, suggesting that the heme pool varies across different tissue types. The expression of heme oxygenase 1 (HO-1) mRNA, which is expressed proportionally to the amount of free heme, were similar to those of free heme levels. Taken together, this study demonstrates that the free heme pool differs across tissues, and that an age-dependent reduction in free heme levels is accelerated in mice heterozygous for [[ALAS1]], which could account for the prediabetic phenotype and mitochondrial abnormality observed in these animals.

|keywords=* 5-Aminolevulinate synthase 1 (ALAS1)
* 5-Aminolevulinic acid (ALA)
* Aging
* Free heme
* Liver
* Skeletal muscle
|full-text-url=https://sci-hub.do/10.1016/j.abb.2020.108721
}}