Heavy fuel oil-contaminated soil remediation by individual and bioaugmentation-assisted phytoremediation with Medicago sativa and with cold plasma-treated M. sativa.

Developing an optimal environmentally friendly bioremediation strategy for petroleum products is of high interest. This study investigated heavy fuel oil (HFO)-contaminated soil (4 and 6 g kg-1) remediation by individual and combined bioaugmentation-assisted phytoremediation with alfalfa (Medicago sativa L.) and with cold plasma (CP)-treated M. sativa. After 14 weeks of remediation, HFO removal efficiency was in the range between 61 and 80% depending on HFO concentration and remediation technique. Natural attenuation had the lowest HFO removal rate. As demonstrated by growth rate and biomass acquisition, M. sativa showed good tolerance to HFO contamination. Cultivation of M. sativa enhanced HFO degradation and soil quality improvement. Bioaugmentation-assisted phytoremediation was up to 18% more efficient in HFO removal through alleviated HFO stress to plants, stimulated plant growth, and biomass acquisition. Cold plasma seed treatment enhanced HFO removal by M. sativa at low HFO contamination and in combination with bioaugmentation it resulted in up to 14% better HFO removal compared to remediation with CP non-treated and non-bioaugmented M. sativa. Our results show that the combination of different remediation techniques is an effective soil rehabilitation strategy to remove HFO and improve soil quality. CP plant seed treatment could be a promising option in soil clean-up and valorization.

Hyperthermia potentiates cisplatin cytotoxicity and negative effects on mitochondrial functions in OVCAR-3 cells.

The aim of this study was to determine the effects of hyperthermia, cisplatin and their combination on mitochondrial functions such as glutamate dehydrogenase (GDH) activity and mitochondrial respiration rates, as well as survival of cultured ovarian adenocarcinoma OVCAR-3 cells. Cells treated for 1 h with hyperthermia (40 and 43 °C) or cisplatin (IC50) or a combination of both treatments were left for recovery at 37 °C temperature for 24 h or 48 h. The obtained results revealed that 43 °C hyperthermia potentiated effects of cisplatin treatment: combinatory treatment more strongly suppressed GDH activity and expression, mitochondrial functions, and decreased survival of OVCAR-3 cells in comparison to separate single treatments. We obtained evidence that in the OVCAR-3 cell line GDH was directly activated by hyperthermia (cisplatin eliminated this effect); however, this effect was followed by GDH inhibition after 48 h recovery. A combination of 43 °C hyperthermia with cisplatin induced stronger GDH inhibition in comparison to separate treatments, and negative effects exerted on GDH activity correlated with suppression of mitochondrial respiration with glutamate + malate. Cisplatin did not induce uncoupling of oxidative phosphorylation in OVCAR-3 cells but induced impairment of the outer mitochondrial membrane in combination with 43 °C hyperthermia. Hyperthermia (43 °C) potentiated cytotoxicity of cisplatin in an OVCAR-3 cell line.

Impact of Gender and Age on Hyperthermia-Induced Changes in Respiration of Liver Mitochondria.

Aim: This study aimed to compare hyperthermia-induced changes in respiration and generation of reactive oxygen species (ROS) in liver mitochondria derived from animals of different gender and age. Methods: The effects of hyperthermia (40⁻47 °C) on oxidation of different substrates and ROS production were estimated in mitochondria isolated from the liver of male and female rats of the 1⁻1.5, 3⁻4, or 6⁻7 months age. Results: Gender-dependent differences in response of respiration to hyperthermia were the highest at 3⁻4 months of age, less so at 6⁻7 months of age, and only minor at juvenile age. Mild hyperthermia (40⁻42 °C) stimulated pyruvate + malate oxidation in mitochondria of females, but inhibited in mitochondria of males in the 3⁻4 month age group. The resistance of mitochondrial membrane to hyperthermia was the highest at 3⁻4 month males, and the lowest in the 6⁻7 month age group. Inhibition of glutamate + malate oxidation by hyperthermia was caused by thermal inactivation of glutamate dehydrogenase. ROS generation at 37 °C was higher at 1⁻1.5 month of age, but the increase in ROS generation with rise in temperature in this age group was the smallest, and the strongest in 6⁻7 month old animals of both genders. Conclusions: The response to hyperthermia varies during the first 6⁻7 months of life of experimental animals: stronger gender dependence is characteristic at 3⁻4 months of age, while mitochondria from 6⁻7 months animals are less resistant to hyperthermia.

Mitochondrial membrane barrier function as a target of hyperthermia.

BACKGROUND AND OBJECTIVE. Hyperthermia is a promising modality for cancer treatment that urgently requires detailed knowledge on molecular and cellular processes for the rational development of treatment protocols. The thorough study of the response of the inner membrane of heart and liver mitochondria to hyperthermia was performed in order to establish the pattern of the hyperthermia-induced changes in the membrane barrier function. MATERIAL AND METHODS. The isolated mitochondria from rat heart and liver (of both genders) were used for experiments, as well as mitochondria isolated from the perfused male rat liver. Changes in the membrane permeability were evaluated by mitochondrial respiration in state 2 or by estimation of the modular kinetics of the membrane leak. RESULTS. The inner membrane of isolated mitochondria from healthy tissues was found to be an extremely sensitive target of hyperthermia that exerted the response even in the febrile range. More severe hyperthermia compromised the inner mitochondrial membrane function; however, this response was tissue-specific and, to some extent, gender-dependent (for liver mitochondria). The data obtained by direct heating of isolated mitochondria were validated by experiments on the perfused liver. CONCLUSIONS. The obtained results imply a crucial importance of the evaluation of the tissue- and gender-specific differences while developing or improving the protocols for hyperthermic treatment or combinatory therapy.