The metabolism of carbohydrates and lipid peroxidation in lead-exposed workers

Abstract

The present study was undertaken to estimate the effect of occupational exposure to lead on the blood concentration of glucose and several enzymes involved in glycolysis, the citric acid cycle, and the pentose phosphate pathway. To estimate the degree of lipid peroxidation, the concentrations of conjugated dienes were determined. The examined group included 145 healthy male employees of lead-zinc works. Taking into account the mean blood lead levels, the examined group was divided into two subgroups. The control group was composed of 36 healthy male administrative workers. The markers of lead exposure were significantly elevated in both subgroups when compared with the controls. There were no significant changes in fasting glucose concentration and fructose-1,6-bisphosphate aldolase activity in the study population. The concentration of conjugated dienes was significantly higher in both subgroups, whereas the activity of malate dehydrogenase was significantly higher only in the group with higher exposure. The activities of lactate dehydrogenase and sorbitol dehydrogenase were significantly decreased in the examined subgroups. The activity of glucose-6-phosphate dehydrogenase decreased significantly in the group with higher exposure and could be the cause of the elevated concentrations of conjugated dienes. It is possible to conclude that lead interferes with carbohydrate metabolism, but compensatory mechanisms seem to be efficient, as glucose homeostasis in lead-exposed workers was not disturbed.

The influence of macro and trace elements on sperm quality

“…Elevated activity of Mn-SOD in seminal plasma in the Me-H group may be a result of a leakage of the enzyme form damaged sperm cells due to oxidative stress and peroxidation of cell membrane lipids. Additionally, the activities of glutathione-related enzymes such as GPx, GST or G6PD, which provides NADPH for reduced glutathione recovery [34], were decreased in the Me-H group compared to those activities in the Me-L group. The activities of SOD and GPx were decreased, despite the increased levels of their cofactors, Cu, Zn, and Se.…”

Oxidative stress and motility impairment in the semen of fertile males

“…Regeneration of the GSH pool depends on the activity of GR, which requires NADPH provided by G6PD. After GPx, GST is the second GSH‐dependent enzyme and is responsible for xenobiotic neutralisation (Atig et al., ; Kasperczyk, Dobrakowski, Ostalowska, Zalejska‐Fiolka, & Birkner, ). Koca et al.…”

“…The decrease in activities of these enzymes might be primary to increased oxidative stress and could be caused by congenital factors. The simultaneously higher activity of Mn‐SOD that was observed in the TOS‐H group is difficult to interpret and could be part of the antioxidant defence response to increased cellular aerobic metabolism, which is a primary source of ROS in spermatozoa (Kasperczyk et al., ). Additionally, we observed similar levels of the thiol groups in both groups, despite a significantly elevated level (by 25%) of albumin, which is an important source of thiol groups, in the TOS‐H group (Dobrakowski, Zalejska‐Fiolka, Wielkoszyński, Świętochowska, & Kasperczyk, ); this finding indirectly suggests decreased levels of other sources of thiols, such as GSH, in the TOS‐H group.…”

A fast, adaptable piecewise gradient method for high-throughput quantification of leaf carotenoids using RP-HPLC-PDA

“…1,2,8 Plant carotenoids also have a signicant impact on humans and animals that are unable to synthesize these compounds. 9,10 More specically, b-carotene can be cleaved in humans to produce vitamin A, 11 while lutein is considered a macular pigment important for maintaining ocular health and visual functionality. 9,10 More specically, b-carotene can be cleaved in humans to produce vitamin A, 11 while lutein is considered a macular pigment important for maintaining ocular health and visual functionality.…”