The time‐dependent effect of gluconasturtiin and phenethyl isothiocyanate on metabolic and antioxidative parameters in rats

Abstract

The effect of gluconasturtiin (GNST) and phenethyl isothiocyanate (PEITC) on some metabolic changes and antioxidative parameters in the rat was tested using different doses of PEITC and duration of GNST or PEITC ingestion. Their effect on antioxidative processes was previously observed, however, their influence on metabolic changes is still poorly characterized. In the performed experiment, the effect of GNST (0.5 mg/kg BW) and PEITC (0.1 mg/kg BW or 0.3 mg/kg BW) administered intragastrically after 4 h or 14 days to growing male rats was studied. PEITC at both doses after 4 h of its administration caused a considerable increase in liver cholesterol and triglyceride content with a concomitant drop in the amount of glycogen. Blood glucose, free fatty acids, phospholipids and total, free, esterified cholesterol as well as cholesterol in high-density lipoprotein were not altered. GNST, at its short-time ingestion, augmented significantly the concentration of triglycerides in blood serum. The compounds tested had no influence on metabolic changes after a longer period of action with the exception of glycogen values in liver, which were substantially augmented by PEITC at both doses. Our trial revealed a lack of GNST and PEITC influence on the content of liver sulphhydryl groups and on glutathione peroxidase and glutathione-S-transferase activities. The only distinct change in the content of malonodialdehyde was observed after short-time action of lower dose of PEITC. Our research showed that the short-term PEITC action constituted a significant factor interfering with liver metabolism. Although PEITC has been repeatedly advocated as very promising anticancer agent, in our experiment, the lower dose of PEITC was revealed as a pro-oxidative substance. These inconsistent properties seem to depend on its dose and time of action.

Phenethyl isothiocyanate potentiates anti‐tumour effect of doxorubicin through Akt‐dependent pathway

“…32 One of the possible mechanisms, by which PEITC exerts its anti-tumour effect, is its proposed antioxidant activity. 33 In accordance with this, our results have shown that upon PEITC treatment, TAC was significantly increased, while MDA level was significantly reduced as compared with EAT/oil control group. Although Dox treatment was able to effectively reduce tumour burden, it caused a significant decreased TAC and increased MDA level as compared with normal control group, and this was in agreement with Qin et al, 34 who demonstrated that Dox induced oxidative stress to the whole body.…”

“…Cellular fatty acids are readily oxidized by ROS to produce lipid peroxyl radicals and lipid hydroperoxides, which propagate into MDA . One of the possible mechanisms, by which PEITC exerts its anti‐tumour effect, is its proposed antioxidant activity . In accordance with this, our results have shown that upon PEITC treatment, TAC was significantly increased, while MDA level was significantly reduced as compared with EAT/oil control group.…”

Acute sulforaphane action exhibits hormonal and metabolic activities in the rat: in vivo and in vitro studies

“…Recent documentation shows that the exposure to SF can also result in a transient ROS burst, the duration and magnitude of which are both dependent on the SF concentration and exposure period (Ferreira de Oliveira et al 2014). The occurrence of oxidative stress reliant on the dose of isothiocyanates and its short-time action was recorded in our previous study (Okulicz et al 2005). SF evoked inflammation at normal glycaemia by a transient production of ROS seems to be highly possible also in the presented short-term study.…”

Antioxidant and pro‐oxidant capacities of ITCs

“…Already in early investigations, the antioxidant properties of ITCs were identified as a key factor for their health-promoting role; very few studies have, however, dealt with a direct assessment of their antioxidant behavior, which has often been inferred from indirect observations. More recently, the pro-oxidant potential of ITCs and the precursor GLs has been documented [Srinivasan et al, 2002;Okulicz et al, 2005], creating a somewhat confusing picture, which appears to be the actual key for understanding the biological interactions of ITCs . In this review, we will summarize and discuss the prevailing mechanisms for the antioxidant and pro-oxidant activity of ITCs, both in vivo and in vitro.…”