Stimulation of iron absorption by polychlorinated aromatic
hydrocarbons.
Oral and intraperitoneal treatment of rats with a single dose of
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 33 microgram/kg, causes a
41--67% increase in iron adsorption in vivo. The major effect is on
the transfer of iron from the mucosa into the bloodstream rather than
on the uptake of iron from the lumen of the gut. These results are
confirmed in studies with everted gut sacs. The effect is maximal at
1--2 days with a dose of 22-42 microgram/kg. Calcium transport is
inhibited by TCDD treatment, whereas galactose and proline transport
are unaffected. Treatment of rats with 1,1,1-trichloro-2,2-bis(p-
chlorophenyl)ethane also stimulates iron transport. Concomitant with
iron transport stimulation, aryl hydrocarbon hydroxylase activity in
the intestine and liver is increased by TCDD treatment. These studies
suggest that polychlorinated aromatic hydrocarbons, which are
environmental health hazards, may effect the intestinal absorption of
essential mineral nutrients. PMID: 443429

Oxidative stress induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin
(TCDD).
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is one of the most potent
toxins and tumor promoters known to man. It is prototypical of many
halogenated polycyclic hydrocarbons that occur as environmental
contaminants. Pathologic lesions produced by these compounds are
mediated by an intracellular receptor protein called the TCDD (Ah)
receptor which functions as a trans-acting effector of gene
expression...Evidence demonstrating the involvement of iron in TCDD-
induced formation of reactive oxygen species and DNA damage is
reviewed. Oxidative damage may contribute to many of the toxic
responses produced by TCDD and its bioisosteres, and may be common to
most of the tissue-damaging effects. PMID: 2210442

Polychlorinated biphenyl-77 induces adipocyte differentiation and
proinflammatory adipokines and promotes obesity and atherosclerosis.
BACKGROUND: Obesity, an inflammatory condition linked to
cardiovascular disease, is associated with expansion of adipose
tissue. Highly prevalent coplanar polychlorinated biphenyls (PCBs)
such as 3,3',4,4'-tetrachlorobiphenyl (PCB-77) accumulate in adipose
tissue because of their lipophilicity and increase with obesity.
However, the effects of PCBs on adipocytes, obesity, and obesity-
associated cardiovascular disease are unknown.... mice injected with
PCB-77 exhibited greater body weight, adipocyte hypertrophy, serum
dyslipidemia, and augmented atherosclerosis. CONCLUSIONS: Our findings
suggest that PCB-77 may contribute to the development of obesity and
obesity-associated atherosclerosis. PMID: 18560532

http://en.wikipedia.org/wiki/Cytochrome_P450
Cytochrome P450 (abbreviated CYP, P450, infrequently CYP450) is a very
large and diverse superfamily of hemoproteins found in all domains of
life. Cytochromes P450 use a plethora of both exogenous and endogenous
compounds as substrates in enzymatic reactions.