The potential protective effect of green, black, red and white tea infusions against adverse effect of cadmium and lead during chronic exposure – A rat model study

Review of polyphenol‐rich products as potential protective and therapeutic factors against cadmium hepatotoxicity

“…Although, there is no doubt that the formation of FR and ROS is the vital process of Cd toxicity during acute exposure (Liu et al, ), the role of oxidative stress in prolonged intoxication with this xenobiotic is less clear. Numerous data from the literature (Table ) (Amamou et al, ; Gałażyn‐Sidorczuk et al, ; Hamden et al, ; Winiarska‐Mieczan, ), including our own studies (Mężyńska et al, ; unpublished data), indicate that chronic low‐level exposure to Cd leads to the induction of oxidative stress in the liver (reflected in decreased values of indices of the enzymatic and non‐enzymatic antioxidative barrier, decreased total antioxidative status [TAS], increased lipid peroxidation, etc.). However, some investigations reveal that chronic exposure to Cd may even decrease the concentration of ROS in the hepatic tissue (Djukić‐Cosić et al, ; Haouem & El Hani, ).…”

“…These investigations show that even a single dose of this toxic metal may lead to hepatocyte damage (Table ). Nevertheless, the highest attention is attached to the investigations developed in animal models corresponding to moderate and low‐level, chronic environmental exposure of humans (Table ) (Amamou et al, ; Brzóska, Gałażyn‐Sidorczuk, et al, ; Gałażyn‐Sidorczuk, Brzóska, Rogalska, Roszczenko, & Jurczuk, ; Hamden, Carreau, Marki, Masmoudi, & El Feki, ; Winiarska‐Mieczan, ). It is very important to underline that experimental studies have revealed that even low and moderate intoxication with Cd, resulting in the liver concentration of this metal ranging from 0.145 to 0.364 μg/g wt and from 0.912 to 2.755 μg/g wt, respectively, leads to the structural and functional damage of this organ (e.g., disruption of oxidative/antioxidative balance, lipid peroxidation, oxidative protein and DNA damage, apoptosis and necrosis of hepatocytes, increase in the serum activities of enzymatic markers of hepatocytes injury) (Gałażyn‐Sidorczuk et al, ; Mężyńska et al, , unpublished data; Rogalska et al, ).…”

“…The favorable impact of polyphenolic compounds on the liver (Figure ) is already applicable in the prevention and treatment of various liver conditions in humans (Boncheva et al, ; Chang et al, ; Ni et al, ; Pezeshki et al, ; Soleimani et al, ). It is very important that polyphenol‐rich food products may be also effective in this organ protection under the conditions of co‐exposure to Cd and various noxious substances, including other heavy metals such as lead (Pb) and arsenic (As), occurring in the natural environment, as well as in many occupational settings (Choudhury et al, ; Kopeć et al, ; Winiarska‐Mieczan, ).…”

“…Camellia sinensis L. is a plant famous for its health‐promoting properties commonly consumed in the form of green or black tea. Many literature sources show that green and black tea extracts have anti‐inflammatory, antibacterial, antiviral, antioxidative, antiobesity, antidiabetic and anticancerogenic properties (Al‐Gnami, ; Chacko, Thambi, Kuttan, & Nishigaki, ; Hamden et al, ; Winiarska‐Mieczan, ). Epidemiological studies report that consumption of green tea may be effective in the prevention of liver‐related adverse events (estimated based on the serum activities of hepatocellular injury markers) and liver cancer (Ni et al, ).…”

“…Green tea polyphenols can scavenge FR and protect cells from oxidative damage (Al‐Gnami, ; Chacko et al, ; Hamden et al, ). Among many favorable effects of green and black tea extract consumption there is also prevention from the harmful impact of Cd on the liver, serum and testes (Abdelrazek, Helmy, Elsayed, Ebaid, & Mohamed, ; Al‐Gnami, ; Hamden et al, ; Mantur et al, ; Winiarska‐Mieczan, )…”