The Cd-Chelex assay: A new sensitive method to determine metallothionein containing zinc and cadmium

Bartsch, Rüdiger; Klein, Dominik; Summer, K

doi:10.1007/bf02010722

Cited by 86 publications

(33 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The supposed MT peaks also took up cadmium, when cadmium was added to the heat denaturated cytosol (Fig. 2) [13,14]. This was another indication of their identity.…”

Section: Identification Of Mt-3 In the Element Profilesmentioning

confidence: 96%

Speciation analysis of trace elements in the brains of individuals with Alzheimer's disease with special emphasis on metallothioneins

Richarz¹,

Βrätter²

2002

Anal Bioanal Chem

View full text Add to dashboard Cite

A speciation analysis of protein-bound elements in the cytosol of human brain was achieved by size exclusion chromatographical separation of the biomolecules and on-line detection of the metal profiles in the eluate by hyphenated inductively coupled plasma-mass spectrometry. Post-mortem samples from Alzheimer's disease brains and from brains of a control group were investigated to elucidate changes in the trace element distribution during the pathological process. Special attention was paid to the metallothioneins (MT) - cysteine-rich, metal-binding proteins of low molecular weight, existing in several isoforms. The isoform MT-3 is found especially in the brain and has a growth inhibition function on neurons. The MT peaks were identified in the element profiles. For this purpose, the metal binding capability and the heat stability of MT were taken into consideration. For verification, a comparison with pure MT-3 was carried out and further biochemical and analytical methods were applied to the fractions of the chromatographical run. A comparison between Alzheimer's disease and control brains showed a significant difference concerning the MT-1/-2 and MT-3 metal levels, leading to the assumption that there were oxidative processes having taken place in the Alzheimer's brain samples.

show abstract

“…The supposed MT peaks also took up cadmium, when cadmium was added to the heat denaturated cytosol (Fig. 2) [13,14]. This was another indication of their identity.…”

Section: Identification Of Mt-3 In the Element Profilesmentioning

confidence: 96%

Speciation analysis of trace elements in the brains of individuals with Alzheimer's disease with special emphasis on metallothioneins

Richarz¹,

Βrätter²

2002

Anal Bioanal Chem

View full text Add to dashboard Cite

show abstract

“…The cadmium saturation assay according to Bartsch et al (1990) was used to quantify the amount of MT in gills, liver, and kidney. Because copper is more strongly bound to MT compared to cadmium and zinc, Cu-MTs are not measured by this method (Funk et al, 1987).…”

Section: Determination Of CD and Zn}metallothionein (Mt)mentioning

confidence: 99%

Stress Responses and Changes in Protein Metabolism in Carp Cyprinus carpio during Cadmium Exposure

Smet

Blust

2001

Ecotoxicology and Environmental Safety

165

View full text Add to dashboard Cite

“…Measurement of islet MT content. Islet MT content was determined using the cadmium-Chelex assay (32). Each assay was performed on a sonicate of 100 -150 islets that had been cultured overnight.…”

mentioning

confidence: 99%

Overexpression of Metallothionein in Pancreatic β-Cells Reduces Streptozotocin-Induced DNA Damage and Diabetes

et al. 2001

View full text Add to dashboard Cite

The release of reactive oxygen species (ROS) has been proposed as a cause of streptozotocin (STZ)-induced ␤-cell damage. This initiates a destructive cascade, consisting of DNA damage, excess activation of the DNA repair enzyme poly(ADP-ribose) polymerase, and depletion of cellular NAD ؉ . Metallothionein (MT) is an inducible antioxidant protein that has been shown to protect DNA from chemical damage in several cell types. Therefore, we examined whether overexpression of MT could protect ␤-cell DNA and thereby prevent STZinduced diabetes. Two lines of transgenic mice were produced with up to a 30-fold elevation in ␤-cell MT. Cultured islets from control mice and MT transgenic mice were exposed to STZ. MT was found to decrease STZ-induced islet disruption, DNA breakage, and depletion of NAD ؉ . To assess in vivo protection, transgenic and control mice were injected with STZ. Transgenic mice had significantly reduced hyperglycemia. Ultrastructural examination of islets from STZ-treated mice showed that MT prevented degranulation and cell death. These results demonstrate that MT can reduce diabetes and confirm the DNA damage mechanism of STZ-induced ␤-cell death. Diabetes 50:2040 -2046, 2001 P ancreatic ␤-cells (1) are extremely vulnerable to damage caused by reactive oxygen species (ROS). A striking example of ␤-cell vulnerability is the severe damage done by streptozotocin (STZ). This natural toxin has several destructive actions, including DNA methylation (2), protein modification (3), and ROS generation (4). STZ enters the cytoplasm via GLUT2, which is the ␤-cell's glucose transporter (5). The presence of this transporter may account for part of the specific vulnerability of the ␤-cell. However, GLUT2 is also present in the liver and kidney, tissues that are relatively resistant to STZ damage. The much greater sensitivity of the ␤-cell is probably due to its very low level of antioxidant enzyme expression and activity (6 -8), which leaves it unable to inactivate ROS. It has been demonstrated in vivo that overexpression of the antiapoptotic, antioxidant protein thioredoxin (9), as well as the antioxidant protein catalase (10), protects the ␤-cell from STZ. However, it is not possible to markedly induce these proteins in vivo. Therefore, we are exploring the potential of another antioxidant protein that is highly inducible, metallothionein (MT).MTs are a family of low-molecular weight cysteine-rich proteins that bind heavy metals with high affinity. MT appears to play important roles in zinc homeostasis and ROS protection. Both functions are due to the presence of abundant cysteine residues. MT protects against many agents known to act through ROS, including hydrogen peroxide, radiation, glutathione depletors, adriamycin, and xanthine oxidase (11,12). MT is distinct among ROS scavengers in the breadth of its protection, in that it scavenges nitric oxide radicals (13), superoxide radicals (14), and hydroxyl radicals (15), which are the most destructive ROS species (11). MT scavenging of hydroxyl radicals is especi...

show abstract

The Cd-Chelex assay: A new sensitive method to determine metallothionein containing zinc and cadmium

Cited by 86 publications

References 10 publications

Speciation analysis of trace elements in the brains of individuals with Alzheimer's disease with special emphasis on metallothioneins

Speciation analysis of trace elements in the brains of individuals with Alzheimer's disease with special emphasis on metallothioneins

Stress Responses and Changes in Protein Metabolism in Carp Cyprinus carpio during Cadmium Exposure

Overexpression of Metallothionein in Pancreatic β-Cells Reduces Streptozotocin-Induced DNA Damage and Diabetes

Contact Info

Product

Resources

About