Porphyrie

The porphyries are characterized affections, in the organization, of massive quantities of Porphyrine S, molecules precursors of the Hème (left not-proteinic the Hémoglobine). They are caused by a disorder of the Métabolisme of the derivatives pyrrolic. The common sign of the porphyries is the presence of porphyrins in the Urine (Porphyrinurie) and in the Fèces.

The acute porphyries appear by abdominal pains ( “colics” ), by nervous and psychic disorders, and can lead to serious bulbar disorders. The accesses intermittent and are improved by the administration of Vitamine B3 (Nicotinamide).

One distinguishes two great types of porphyrie,

the porphyries induced by Intoxication S (Heavy metals), reversible if the intoxication did not relate to the Fetus, the Embryon or the young child.
the porphyries Congénital be, which constitute true essential diseases, and can to a certain extent to be neat. The chronic porphyrie , congenital or disease of Günther , appears as of childhood and persists in an adult state in the form of bulleuses cutaneous eruptions on the areas of the body exposed to the sun; they are often accompanied by various lesions Dystrophique S.
the cutaneous porphyrie resembles the preceding one, but is not accompanied by dystrophies, and can appear at the adulthood.

Metabolic ways: implied enzymes

There is eight Enzyme S in the biosynthetic way of the Hème; the first and the three last are in the Mitochondrie, whereas the four others are in the Cytosol:

δ-aminolévulinate (WENT or δ-ALA) synthase
δ-aminolévulinate (WENT or δ-ALA) dehydratase
hydroxyméthylbilane (HMB) synthase
uroporphyrinogene (URO) synthase
uroporphyrinogene (URO) décarboxylase
coproporphyrinogene (COPRO) oxydase
protoporphyrinogene (PROTO) oxydase
ferrochélastase

Erythropoietic Porphyries hepatic and porphyries

the hepatic porphyries are:

deficiency WENT from there intermittent dehydratase
Porphyrie acute (AIP): a deficiency in hereditary HMB synthase
coproporphyrie English (: hereditary coproporphyria ) (HCP): a deficiency in COPRO oxydase
variegate porphyria (VP): a deficiency in PROTO oxydase
porphyria cutanea delayed (PCT): a deficiency in erythropoietic URO décarboxylase

the porphyries are:

weakens sideroblastic related to X (in English: X-linked sideroblastic weakened ) (XLSA): a deficiency WENT from there synthase
porphyrie erythropoietic congenital English (: congenital erythropoietic porphyria ) (STOCK): a deficiency in erythropoietic URO synthase
protoporphyrie English (: erythropoietic protoporphyria ) (EPP): a deficiency in ferrochélatase

Mixed Porphyrie

The mixed porphyrie , or porphyrie variegata , associates the signs of the acute porphyrie with those of the cutaneous porphyrie. Since the adolescence, where the disease appears, the evolution worsens the signs Neuropsychique S and death can occur by bulbar attack. The mixed porphyrie concerns primarily the populations of South Africa, of Dutch origin, descendant of the same ancestor, Berrit Janisz, emigrant of Holland at the XVIIe century.

Anecdotes

The king George III of England has seems it reached of porphyrie. The drugs that it took for that were probably contaminated by Arsenic, which could explain its episodes of madness.

Vincent van Gogh could have also been victim of porphyrie, in particular when it cut the right ear to give it to a prostitute. It could also be poisoned by the pigments of its paintings (Plomb, Cadmium, Arsenic…).

Vampire or Werewolf: the congenital porphyries, due to a deficiency of genetic cause in Enzyme S allowing the synthesis of the Heme S, are pathologies related to accumulation in blood and the fabrics of Porphyrine S. This accumulation causes systemic disorders and intoxications whose symptoms are variable. Among the brought back symptoms, one finds in particular a épidermolyse (destruction of the skin) following exposures to solar light, a coloring of the teeth and nails transfering towards the red (the porphyrins exposed to the light are Pigment S purple-reds), a Nécrose conjunctive fabrics, of which the Gencive S, emphasizing the teeth, an abnormally fast growth of the hair… These symptoms brought scientists, in particular the biochemist David Dolphin, to put forth the assumption that the observation of case of porphyrie probably supported and can be inspired the myths of the Loup-garou and of the Vampire. Elaine Marieb, in its work human Anatomy and physiology , refers to the bond between the porphyrie and these myths.

Sources

Article of E. Willett: http://www.edwardwillett.com/Columns/werewolvesvampires.htm (in English)
document pdf on a conference of David Dolphin: http://artsandscience1.concordia.ca/chem/seminar/dolphin.pdf
Marieb, NR. Elaine, human Anatomy and physiology , Third edition, ERPI, 2005

See too

Heme

External bonds

European Porphyria Initiative
/the French Center of Porphyries

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