Oral Dimercaptosuccinic Acid and Ongoing Exposure to Lead: Effects on Heme Synthesis and Lead Distribution in a Rat Model

Effects of N-acetylcysteine and 2,3-dimercaptosuccinic acid on lead induced oxidative stress in rat lenses

“…Succimer is effective in lowering blood Pb levels in children with severe Pb poisoning (\ 45 mg/dl). Succimer also decreases the Pb burden of soft tissues such as blood, brain, and kidney (Mann and Tavers, 1991) and also removes Pb from bone (Pappas et al, 1995). In the present study, Pb chelation resulted in a partial restoration of the lens redox status as evidenced by increases in the GSH levels and decreases in the PSSG and MDA levels.…”

Oral succimer decreases the gastrointestinal absorption of lead in juvenile monkeys.

“…A reduction in body Pb retention was evident with the recovery of both oral 206 Pb and iv 204 Pb tracers, again indicating that succimer acts equally on Pb from past chronic exposures and recent oral exposures concurrent with treatment ( Figure 3). This outcome is consistent with several previous rodent studies which showed that oral succimer decreased the whole-body retention (10) and tissue accumulation (27) of Pb derived from concurrent oral Pb exposures. These data are in contrast with a previous rodent study of several other chelating agents, including BAL, citrate, and penicillamine, which suggested that these agents may increase the body absorption and retention of Pb from exposures suffered concurrent with treatment (11).…”

ALAD (δ-aminolevulinic Acid Dehydratase) as Biosensor for Pb Contamination

“…Therefore, δ-ALAD is inhibited by substances that compete with zinc and/or that oxidize the -SH groups (Farina et al 2002, Nogueira et al 2003a-b, Santos et al 2004 and is linked to situations associated with oxidative stress , Pande et al 2001, Pande & Flora 2002, Tandon et al 2002, Soares et al 2003. In addition, human exposure to Pb 2+ causes an important inhibition of blood δ-ALAD (Meredith et al 1979, Fujita et al 1981, Pappas et al 1995, Polo et al 1995, Pires et al 2002 and is associated with an intense anemia accompanied by an increase in urinary δ-ALA excretion (Oskarsson 1989). Therefore, δ-ALAD activity is used as one of the most reliable indicators of Pb 2+ intoxication in humans and other animals (Meredith et al 1979, Pappas et al 1995.…”

“…In addition, human exposure to Pb 2+ causes an important inhibition of blood δ-ALAD (Meredith et al 1979, Fujita et al 1981, Pappas et al 1995, Polo et al 1995, Pires et al 2002 and is associated with an intense anemia accompanied by an increase in urinary δ-ALA excretion (Oskarsson 1989). Therefore, δ-ALAD activity is used as one of the most reliable indicators of Pb 2+ intoxication in humans and other animals (Meredith et al 1979, Pappas et al 1995. ALADs have been purifed from a wide variety of sources, including bovine liver (Gibson et al 1955), human erythrocytes (Anderson & Desnick 1979), Rhodopseudomonas capsulatus, Rhodobacter sphaeroides, (Nandi & Shemin 1973;Nandi et al 1968), Escherichia coli (Spencer & Jordan 1993) and spinach, Spinacia oleracea (Liedgens et al 1983) during the time.…”