Metal Toxicity and Treatment Mechanisms

Christine O'Connor discusses metal toxicity and metal drugs, classifying metals into Class A and Class B based on their interaction with ligands. Class A metals form stable complexes with lighter ligands and are generally non-toxic, while Class B metals form stable complexes with heavier ligands and are toxic. The video explains how metals become toxic, the use of chelating ligands for treatment, and provides examples of metal poisoning and treatments. It also covers the use of EDTA and the benefits of metal drugs in treating diseases like cancer.

Which class of metals forms stable complexes with lighter ligands and is generally non-toxic?

• Class A metals

• Class B metals

• Heavy metals

• Noble metals

What is the primary reason Class B metals are considered toxic?

• They are small and non-polarizable

• They are large and easily polarizable

• They are essential for biological functions

• They form stable complexes with lighter ligands

What is a key requirement for a chelating ligand used in metal toxicity treatment?

• It must be a heavy metal

• It must be insoluble

• It must be non-toxic

• It must be a hard base

Which metal's toxicity is treated with the antidote dimer capral?

• Iron

• Arsenic

• Lead

• Copper

What is the role of penicillamine in treating Wilson's disease?

• It increases copper levels

• It removes excess copper

• It acts as a calcium supplement

• It binds to iron

Why is EDTA not administered orally for metal poisoning treatment?

• It is too expensive

• It is too potent

• It is hydrophilic and does not reach enzyme sites

• It causes severe side effects

What is a major disadvantage of using EDTA in metal poisoning treatment?

• It is only effective against copper

• It is unselective and may remove essential metals

• It acts very quickly

• It is highly selective

How do synthetic metal chelates help in treating infections?

• By reducing metal absorption

• By enhancing bacterial growth

• By inactivating viruses through physical interactions

• By increasing metal toxicity

What is the mechanism of action for cisplatin in cancer treatment?

• It acts as a calcium channel blocker

• It removes essential metals from cells

• It forms cross-links in DNA, inhibiting synthesis

• It enhances DNA synthesis

Why is the cis isomer of cisplatin effective against tumors?

• It binds to calcium ions

• It is more soluble than the trans isomer

• It matches the distance between DNA nitrogen atoms

• It is less toxic than the trans isomer