The Effects of Cadmium Toxicity

Abstract

Cadmium (Cd) is a toxic non-essential transition metal that poses a health risk for both humans and animals. It is naturally occurring in the environment as a pollutant that is derived from agricultural and industrial sources. Exposure to cadmium primarily occurs through the ingestion of contaminated food and water and, to a significant extent, through inhalation and cigarette smoking. Cadmium accumulates in plants and animals with a long half-life of about 25–30 years. Epidemiological data suggest that occupational and environmental cadmium exposure may be related to various types of cancer, including breast, lung, prostate, nasopharynx, pancreas, and kidney cancers. It has been also demonstrated that environmental cadmium may be a risk factor for osteoporosis. The liver and kidneys are extremely sensitive to cadmium’s toxic effects. This may be due to the ability of these tissues to synthesize metallothioneins (MT), which are Cd-inducible proteins that protect the cell by tightly binding the toxic cadmium ions. The oxidative stress induced by this xenobiotic may be one of the mechanisms responsible for several liver and kidney diseases. Mitochondria damage is highly plausible given that these organelles play a crucial role in the formation of ROS (reactive oxygen species) and are known to be among the key intracellular targets for cadmium. When mitochondria become dysfunctional after exposure to Cd, they produce less energy (ATP) and more ROS. Recent studies show that cadmium induces various epigenetic changes in mammalian cells, both in vivo and in vitro, causing pathogenic risks and the development of various types of cancers. The epigenetics present themselves as chemical modifications of DNA and histones that alter the chromatin without changing the sequence of the DNA nucleotide. DNA methyltransferase, histone acetyltransferase, histone deacetylase and histone methyltransferase, and micro RNA are involved in the epigenetic changes. Recently, investigations of the capability of sunflower (Helianthus annuus L.), Indian mustard (Brassica juncea), and river red gum (Eucalyptus camaldulensis) to remove cadmium from polluted soil and water have been carried out. Moreover, nanoparticles of TiO2 and Al2O3 have been used to efficiently remove cadmium from wastewater and soil. Finally, microbial fermentation has been studied as a promising method for removing cadmium from food. This review provides an update on the effects of Cd exposure on human health, focusing on the cellular and molecular alterations involved.

Vitamin C Protects Porcine Oocytes From Microcystin-LR Toxicity During Maturation

“…Meanwhile, the demethylase KDM5B mRNA level was significantly changed by MC-LR exposure, indicating that MC-LR meiotic maturation failure may result from an impairment of epigenetic modifications in porcine oocytes. These results consistent with the opinion which indicated that pollutants might cause cell dysfunctions via epigenetic modifications ( Genchi et al, 2020 ; Zheng et al, 2020 ). However, VC restored these abnormal epigenetic alterations in MC-LR-exposed oocytes.…”

Phytoremediation of Cadmium: Physiological, Biochemical, and Molecular Mechanisms

“…For example, Cd exposure influences the human male reproductive organs/system and deteriorates spermatogenesis and semen quality, especially sperm motility and hormonal synthesis/release. Based on experimental and human studies, it also impairs female reproduction and the reproductive hormonal balance and affects menstrual cycles [ 16 , 17 ]. In animals, experimental studies revealed that Cd and Cd compounds (referred to as Cd) by multiple routes of exposure prompt benign and malignant tumor formation at various sites in many species of experimental animals [ 18 ].…”

The association of cadmium and lead exposures with red cell distribution width

“…Evidence suggests that the heavy metals cadmium and lead interfere with a number of functions of the erythropoietic system, the processes that make red blood cells. In addition, both cadmium and lead are highly bound to intracellular and membrane proteins in the red blood cell [ 1 , 2 ], complicating analysis of their effects on erythropoiesis. Both metals are also toxic to the kidney [ 3 ], which is the site of erythropoietin synthesis, the primary hormone that stimulates red blood cell generation in the bone marrow [ 4 ].…”