Cadmium effects

Mottled teeth just like "fluorosis"...
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Cadmium effects

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The cadmium effects described below are largely identical to those observed in the literature on the molecular actions of fluoride.

See also: Dental Fluorosis = Dental Cadmiosis

Misra UK, Gawdi G, Pizzo SV - "Induction of mitogenic signalling in the 1LN prostate cell line on exposure to submicromolar concentrations of cadmium+" Cell Signal 15(11):1059-70 (2003)

Cadmium exposure increases the risk of prostate cancer. We now describe the effects of Cd2+ on signalling and proliferation in 1LN prostate cells. Cd2+ increased [3H]thymidine uptake and cell number twofold. Cd2+ elevated intracellular IP3, cytosolic-free Ca2+, phosphorylated MEK1/2, ERK1/2, p38 MAPK and JNK two- to threefold. Increased PDK1 and phosphorylation of the 85-kDa regulatory subunit of PI 3-kinase, Akt and p70s6k were also observed. Cd2+ treatment increased transcription factors NFkappaB and CREB, and the expression of c-fos and c-myc. Cd2+-induced increased uptake of [3H]thymidine was abolished by translational and transcriptional inhibitors, and Ca2+ channel blockers. Inhibition of phospholipase C and of Ca2+ binding to IP3 receptors inhibited Cd2+-induced DNA synthesis as did inhibition of tyrosine kinases, protein kinase C, PI 3-kinase, farnesyl transferase, MEK1/2, ERK1/2 and p38MAPK. Thus signalling events, which are triggered on exposure of 1LN cells to submicromolar
concentrations of Cd2+, induce increased proliferation of these cells.
Kakei M, Sakae T, Yoshikawa M -" Mechanism of cadmium induced crystal defects in developing rat tooth enamel" Proc Jpn Acad Ser B Phys Biol Sci 85(10):500-7 (2009)

It is well known that exposure to environmental cadmium causes itai-itai (ouch-ouch) disease. However, the exact mechanism underlying this bone disease remains unresolved. By focusing on the calcification mechanism, we examined developing tooth enamel in rats exposed to cadmium to test the hypothesis that cadmium exposure may cause defects in crystal formation. Electron microscopy revealed the presence of perforated crystals in developing tooth enamel, indicating that the process of crystal nucleation may have been interrupted by cadmium exposure. Furthermore, biochemical analyses revealed that the catalytic activity of carbonic anhydrase in the immature enamel matrix declined remarkably despite the fact that quantitative reduction of this enzyme was insignificant, suggesting that the decline of catalytic activity may have resulted from the replacement of zinc with cadmium ions. Therefore, we concluded that the poor catalytic activity of cadmium-binding carbonic anhydrase might hinder the nucleation process, leading to an impairment in mineralization that causes itai-itai disease.
Wöltgens JH, Lyaruu DM, Bervoets TJ -" Possible functions of alkaline phosphatase in dental mineralization: cadmium effects" J Biol Buccale 19(2):125-8 (1991)

In mineralizing dental tissues the non-specific alkaline phosphatase, using paranitrophenylphosphate (p-NPP) as substrate, is also capable of splitting inorganic pyrophosphate (PPi). In contrast to the p-NPP-ase part of the enzyme, the PPi-ase part requires Zn2+ as a cofactor for its hydrolytic activity. The PPi-ase activity of the enzyme can be inhibited by cadmium ions (Cd2+), perhaps by replacing Zn2+ from the active site of the enzyme molecule. In addition to splitting PPi, the PPi-ase part of the enzyme may also be involved in the phosphorylation process of yet undetermined organic macromolecules. Cd2+ inhibits this phosphorylation process. Inhibition of the PPi-ase activity can also be accomplished by ascorbic acid known for its capacity to complex bivalent cations. Ascorbic acid may accordingly also remove Zn2+ from the active site of the PPi-ase. It is suggested that in developing dental tissues alkaline phosphatase is not only associated with the transport of phosphate ions towards the mineralization front, but is also involved in the phosphorylation of organic macromolecules, a process activated the PPi-ase part of the enzyme.

Kong A, Zhang Y, Ning B, Li K, Ren Z, Dai S, Chen D, Zhou Y, Gu J, Shi H - "Cadmium induces triglyceride levels via microsomal triglyceride transfer protein (MTTP) accumulation caused by lysosomal deacidification regulated by endoplasmic reticulum (ER) Ca2+ homeostasis" Chem Biol Interact. 348:109649 (2021)
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