Protoporphyrin IX


Also found in: Wikipedia.

Protoporphyrin IX

Protoporphyrin IX is a protein. The measurement of this protein is useful for the assessment of iron status. Hemoglobin consists of a complex of a protein plus heme. Heme consists of iron plus protoporphyrin IX. Normally, during the course of red blood cell formation, protoporphyrin IX acquires iron, to generate heme, and the heme becomes incorporated into hemoglobin. However, in iron deficiency, protophoryrin IX builds up.
References in periodicals archive ?
Visualizing carcinomas of the mouth cavity by stimulating synthesis of fluorescent protoporphyrin IX. Mund Kiefer Gesichtschir.
Recent studies have focused on incorporating specific substrates of BOx such as bilirubin, quinones, syringaldazine, and protoporphyrin derivatives such as protoporphyrin IX iron (III) (PPFeIII), protoporphyrin IX dimethyl ester (PPDE), and octaethylporphyrin (OEP) towards appropriate orientation that can be convenient for DET-type electrocatalysis [36].
A separate study of 12 healthy adults found that pretreatment with an ablative fractional laser significantly intensifies protoporphyrin IX fluorescence to a larger extent than curettage, microdermabrasion, microneedling, and nonablative fractional laser (JAMA Derm.
Some genetic pathways leading to build-up of protoporphyrin IX have already been described, but many cases of EPP remain unexplained.
HO activity was inhibited by tin protoporphyrin IX (SnPP, 30.0 [micro]g/kg, pH 7.4, s.c., 24 h and 1 h pretreatment).
Further researches on the characteristics of chlorophyll metabolism indicated that the precursors of D-aminolevulinic acid (ALA), porphobilinogen (PBG), uroporphyrinogen III (Urogen III), coproporphyrinogen III (Coprogen III), protoporphyrin IX (Proto IX), Mg-protoporphyrin IX (Mg-Proto IX) and protochlorophyllide (Pchlide) in chlorophyll biosynthesis in Burley21 were lower than in Maryland609 at vigorous growing period; the activity of D-aminolevulinate dehydratase (ALAD) in Burley21 was 0.43% as compared to Maryland609, but the activity of chlorophyllase in Burley21 was 2.04 times as high as in that of Maryland609.
However, when cells are exposed to excess exogenous 5-ALA as a drug, the negative feedback control mechanism of 5-ALA synthesis is bypassed, leading to protoporphyrin IX accumulation in the mitochondria of malignant tissues where ferrochelatase enzyme is absent.
The active substance in GLIOLAN, aminolevulinic acid (ALA), is a photoreceptive compound which is absorbed by cells in the body, where it is converted by enzymes into fluorescent chemicals, particularly protoporphyrin IX (PPIX).
(1,2) Ferrochelatase is the last enzyme in the heme biosynthetic pathway, which is responsible for the incorporation of iron onto protoporphyrin IX. (1) Ferrochelatase activity in patients with EPP is typically 10% to 25% of normal, resulting in an accumulation of protoporphyrin IX in the skin, erythrocytes, liver, and plasma.
N-alkylporphyrins distort or bend protoporphyrin IX, inhibiting the production of heme (as in hemoglobin).
(1.) Kennedy JC, Pottier RH, Pross DC: Photodynamic therapy with endogenous protoporphyrin IX: basic principles and present clinical experience.
The condition is caused by a deficiency of ferrochelatase, which leads to accumulation of protoporphyrin IX. Treatment involves sun avoidance, sunscreens, and beta-carotene 30-150 mg/day.