Multifunctional System for Combined Chemodynamic–Photodynamic Therapy Employing the Endothelin Axis Based on Conjugated Polymer Nanoparticles

2021 ◽  
Author(s):  
Khalaf Ahmed Jasim ◽  
Ibrahim Waheed ◽  
Martin Topps Topps ◽  
Andre J Gesquiere

Most nanomedicines that attack tumors by Reactive Oxygen Species (ROS) based on lipid peroxidation mechanisms require external activation to work. The leading example is Photodynamic Therapy (PDT), for which an...

2012 ◽  
Vol 48 (4) ◽  
pp. 659-665 ◽  
Author(s):  
Aline Emmer Ferreira Furman ◽  
Railson Henneberg ◽  
Priscila Bacarin Hermann ◽  
Maria Suely Soares Leonart ◽  
Aguinaldo José do Nascimento

Sickle cell disease promotes hemolytic anemia and occlusion of small blood vessels due to the presence of high concentrations of hemoglobin S, resulting in increased production of reactive oxygen species and decreased antioxidant defense capacity. The aim of this study was to evaluate the protective action of a standardized extract of Ginkgo biloba (EGb 761), selected due to its high content of flavonoids and terpenoids, in erythrocytes of patients with sickle cell anemia (HbSS, SS erythrocytes) subjected to oxidative stress using tert-butylhydroperoxide or 2,2-azobis-(amidinepropane)-dihydrochloride, in vitro. Hemolysis indexes, reduced glutathione, methemoglobin concentrations, lipid peroxidation, and intracellular reactive oxygen species were determined. SS erythrocytes displayed increased rates of oxidation of hemoglobin and membrane lipid peroxidation compared to normal erythrocytes (HbAA, AA erythrocytes), and the concentration of EGb 761 necessary to achieve the same antioxidant effect in SS erythrocytes was at least two times higher than in normal ones, inhibiting the formation of intracellular reactive oxygen species (IC50 of 13.6 µg/mL), partially preventing lipid peroxidation (IC50 of 242.5 µg/mL) and preventing hemolysis (IC50 of 10.5 µg/mL). Thus, EGb 761 has a beneficial effect on the oxidative status of SS erythrocytes. Moreover, EGb 761 failed to prevent oxidation of hemoglobin and reduced glutathione at the concentrations examined.


2012 ◽  
Vol 1 (1) ◽  
pp. 18
Author(s):  
Amrit Kaur Bansal ◽  
Ranjna Sundhey Cheema ◽  
Vinod Kumar Gandotra

The aim of this paper was to investigate the antioxidant effect of Mn2+ (200 mM) on the sperm capacitation and acrosome reaction of fresh and chilled cattle bull semen. It has been found that Mn2+ supplementation improves (P≤0.05) the motility at 0, 2, 4 and 6 h of incubation. MDA (malondialdehyde), end product of lipid peroxidation, decreases significantly (P≤0.05) with the supplementation of manganese at 0- and 6-hr of incubation both in fresh and chilled semen. Manganese also increases acrosome reaction significantly (P≤0.05) both in fresh and chilled semen at 0, 4 and 6 h of incubation. Therefore, our findings suggest the role of Mn2+supplementation in improving the quality of cattle bull semen by its scavenging property<em> i.e.</em> reduction in the production of reactive oxygen species during its storage at 4°C or incubation at 37°C for capacitation.


2015 ◽  
pp. 849-856 ◽  
Author(s):  
M. VOKURKOVÁ ◽  
H. RAUCHOVÁ ◽  
L. ŘEZÁČOVÁ ◽  
I. VANĚČKOVÁ ◽  
J. ZICHA

Hypothalamic paraventricular nucleus (PVN) and rostral ventrolateral medulla (RVLM) play an important role in brain control of blood pressure (BP). One of the important mechanisms involved in the pathogenesis of hypertension is the elevation of reactive oxygen species (ROS) production by nicotine adenine dinucleotide phosphate (NADPH) oxidase. The aim of our present study was to investigate NADPH oxidase-mediated superoxide (O2-) production and to search for the signs of lipid peroxidation in hypothalamus and medulla oblongata as well as in renal medulla and cortex of hypertensive male rats transgenic for the murine Ren-2 renin gene (Ren-2 TGR) and their age-matched normotensive controls ‒ Hannover Sprague Dawley rats (HanSD). We found no difference in the activity of NADPH oxidase measured as a lucigenin-mediated O2- production in the hypothalamus and medulla oblongata. However, we observed significantly elevated NADPH oxidase in both renal cortex and medulla of Ren-2 TGR compared with HanSD. Losartan (LOS) treatment (10 mg/kg body weight/day) for 2 months (Ren-2 TGR+LOS) did not change NADPH oxidase-dependent O2- production in the kidney. We detected significantly elevated indirect markers of lipid peroxidation measured as thiobarbituric acid-reactive substances (TBARS) in Ren-2 TGR, while they were significantly decreased in Ren-2 TGR+LOS. In conclusion, the present study shows increased NADPH oxidase activities in renal cortex and medulla with significantly increased TBARS in renal cortex. No significant changes of NADPH oxidase and markers of lipid peroxidation were detected in the studied brain regions.


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