Evaluation of the safety profile and antioxidant activity of fatty hydroxamic acid from underutilized seed oil of Cyperus esculentus

Mitochondrial alternative oxidase contributes to successful tardigrade anhydrobiosis

Anhydrobiosis can be described as an adaptation to lack of water that enables some organisms, including tardigrades, to survive extreme conditions, even some that do not exist on Earth. The cellular mechanisms underlying anhydrobiosis are still not completely explained including the putative contribution of mitochondrial proteins. Since mitochondrial alternative oxidase (AOX), described as a drought response element in plants, was recently proposed for various invertebrates including tardigrades, we investigated whether AOX is involved in successful anhydrobiosis of tardigrades. Milnesium inceptum was used as a model for the study. We confirmed functionality of M. inceptum AOX and estimated its contribution to the tardigrade revival after anhydrobiosis of different durations. We observed that AOX activity was particularly important for M. inceptum revival after the long-term tun stage but did not affect the rehydration stage specifically. The results may contribute to our understanding and then application of anhydrobiosis underlying mechanisms.

Green synthesized hydroxamic acid administered in high dose disrupts the antioxidant balance in the hepatic and splenic tissues of albino rats

Background

Hydroxamic acids are currently being used in diverse biological activities. We investigated the effect of hydroxamic acid, synthesized from Cyperus esculentus seeds, on the antioxidant status of the liver, spleen, and kidney of Wistar rats.

Methods

Twenty male rats were randomly divided into three treatment groups using hydroxamic acid at doses of 5, 15, and 50 mg/kg and a control group using distilled water. Rats were sacrificed 24 h after a seven-day repeated oral dosing. After that, the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and the levels of glutathione (GSH) and malondialdehyde (MDA) were investigated in the organs.

Results

Our data showed that MDA levels remained unaltered in the liver, spleen, and kidney. However, it was found that hydroxamic acid at the dose of 50 mg/kg significantly increased SOD activity but depleted CAT, GPx activities and GSH levels in the liver when compared to the control groups. In splenic tissue, SOD activity and GSH levels were significantly diminished. Contrarily, in the kidney, treatment of rats with 50 mg/kg hydroxamic acid did not affect SOD activity, but GPx activity was increased while GST activity was decreased when compared to the controls.

Conclusion

Overall, hydroxamic acid may enhance antioxidant enzyme activities in the liver and kidney. However, caution is required at higher doses to forestall oxidative stress in the hepatic and splenic tissues.

Alterations in morphology and hepatorenal indices in rats subacutely exposed to bitumen extract

Bitumen is a complex mixture of dense and extremely viscous organic liquids produced by distillation of crude oil during petroleum refining. Nigeria has a large deposit of natural bitumen, yet to be fully exploited. Discharges of petroleum hydrocarbons and other petroleum-derived products have caused environmental pollution and adverse human health effects in several oil-rich communities. In this study, bitumen obtained from a seepage source in Agbabu, the town of first discovery, was used in sub-acute toxicity studies in a rat experimental model, in order to assess potential health risks posed to local populace sequel to full exploitation of bitumen. Dosages were chosen to accommodate low to high cases of environmental exposures. Male Wistar rats were administered, per os, dosages of bitumen extract at 5, 3, 2, and 1 mg/kg body weight. Following euthanasia 28 days later, histological findings revealed severe portal congestion and cellular infiltration in the liver, while in the kidney there were protein casts in the tubular lumen. The relative liver and kidney weights in the 5 mg/kg groups were 34% and 40% higher than in the controls, with a concomitant decrease in food and water consumption. Furthermore, plasma clinical analyses revealed marked elevation in aspartate aminotransferase and triglycerides levels in bitumen extract-intoxicated rats. The results indicate the potential hepatorenal toxicity in adult rats following repeated exposure to bitumen extract.