scholarly journals Oxidative Stress Biomarkers in Erythrocytes of Captive Pre-Juvenile Loggerhead Turtles Following Acute Exposure to Methylmercury

2020 ◽  
Vol 10 (10) ◽  
pp. 3602 ◽  
Author(s):  
Javier Hernández-Fernández ◽  
Ellie Anne López-Barrera ◽  
Leonardo Mariño-Ramírez ◽  
Pilar Rodríguez-Becerra ◽  
Andrés Pinzón-Velasco

This study describes the use of erythrocytes (RBCs) of loggerhead turtles as in vitro models for evaluating their toxicity to methylmercury. Blood samples of loggerhead turtles that were born in the Colombian Caribbean were used. The LC50 of RBCs to methylmercury was determined at 96 h using methylmercury concentrations of 0.5–100 mg L−1. Next, the viability of the RBCs and the activity of the enzymes superoxide dismutase (SOD), glutathione S-transferase (GST), and lipid peroxidation by malondialdehyde (MDA) at 6 and 12 h of exposure to acute concentrations of 0, 1, and 5 mg L−1 were evaluated. The LC50 for loggerhead turtle RBCs was 8.32 mg L−1. The cell viability bioassay of RBCs exposed for 12 h only showed 100% cell viability. Increasing in vitro MeHg concentrations caused a corresponding increase in MDA concentration as well as decreases in the activities of SOD and GST. The RBCs represent an excellent model for ecotoxicological studies and SOD, GST, and MDA are biomarkers of environmental pollution and oxidative stress in loggerhead turtles. This was the first study conducted on loggerhead turtle where the response of RBCs to MeHg-induced oxidative stress is evaluated.

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Lisiane Conte ◽  
Sabrina Somacal ◽  
Sabrina Marafiga Nichelle ◽  
Cristine Rampelotto ◽  
Silvino Sasso Robalo ◽  
...  

Lycopene-based medications and supplements have been developed to prevent atherosclerosis, primarily because of their ability to decrease low-density lipoprotein (LDL) oxidation. Bixin and norbixin are carotenoids found in the seeds of annatto (Bixa orellana) and are colorants widely used by the food industry. Some studies have already demonstrated that these compounds have antioxidant and antiatherogenic potential in vitro and in animal models, but there is no evidence supporting the effects of their long-term or short-term consumption by humans. The aim of this study was to evaluate the effects of short-term intake of annatto carotenoids on biochemical and oxidative stress biomarkers as well as on the susceptibility of LDL oxidation in healthy individuals, using lycopene as a positive control. The effect of daily supplementation (0.05 mg/kg of body weight (b.w.)) with bixin, norbixin, lycopene, or placebo for 7 days was evaluated in a randomized, controlled crossover study in 16 healthy volunteers (8 men and 8 women). The susceptibility of LDL to Cu2+-induced oxidation ex vivo, biochemical parameters, and oxidative stress biomarkers were evaluated. No treatment affected biochemical parameters or most oxidative stress biomarkers. However, bixin reduced the oxidation rate of the LDL lipid moiety (−275%, p<0.1) and nitric oxide metabolites (NOx) (−460%, p<0.1), compared to the placebo group. Moreover, we observed that the changes in these parameters were positively associated, supporting the hypothesis that bixin decreases the susceptibility of LDL to Cu2+-induced oxidation by decreasing NOx levels, probably by downregulating the inducible nitric oxide synthase.


2018 ◽  
Vol 9 (12) ◽  
pp. 6508-6516 ◽  
Author(s):  
Marta Esgalhado ◽  
Julie A. Kemp ◽  
Renata Azevedo ◽  
Bruna R. Paiva ◽  
Milena B. Stockler-Pinto ◽  
...  

Prebiotic-resistant starch supplementation may be a good strategy to reduce inflammation, oxidative stress and uremic toxins in CKD patients.


Chemosphere ◽  
2016 ◽  
Vol 160 ◽  
pp. 95-103 ◽  
Author(s):  
Diogo Cruz ◽  
Ângela Almeida ◽  
Vânia Calisto ◽  
Valdemar I. Esteves ◽  
Rudolf J. Schneider ◽  
...  

2018 ◽  
Vol 19 (11) ◽  
pp. 3349 ◽  
Author(s):  
Jin Namkoong ◽  
Dale Kern ◽  
Helen Knaggs

Since the skin is the major protective barrier of the body, it is affected by intrinsic and extrinsic factors. Environmental influences such as ultraviolet (UV) irradiation, pollution or dry/cold air are involved in the generation of radical oxygen species (ROS) and impact skin aging and dermal health. Assessment of human skin gene expression and other biomarkers including epigenetic factors are used to evaluate the biological/molecular activities of key compounds in cosmetic formulas. The objective of this study was to quantify human gene expression when epidermal full-thickness skin equivalents were exposed to: (a) a mixture of betaine, pentylene glycol, Saccharomyces cerevisiae and Rhodiola rosea root extract (BlendE) for antioxidant, skin barrier function and oxidative stress (with hydrogen peroxide challenge); and (b) a mixture of Narcissus tazetta bulb extract and Schisandra chinensis fruit extract (BlendIP) for various biomarkers and microRNA analysis. For BlendE, several antioxidants, protective oxidative stress biomarkers and many skin barrier function parameters were significantly increased. When BlendE was evaluated, the negative impact of the hydrogen peroxide was significantly reduced for the matrix metalloproteinases (MMP 3 and MMP 12), the skin aging and oxidative stress biomarkers, namely FBN2, ANXA1 and HGF. When BlendIP was tested for cell proliferation and dermal structural components to enhance the integrity of the skin around the eyes: 8 growth factors, 7 signaling, 7 structural/barrier function and 7 oxidative stress biomarkers were significantly increased. Finally, when BlendIP was tested via real-time RT-PCR for microRNA expression: miR-146a, miR-22, miR155, miR16 and miR21 were all significantly increased over control levels. Therefore, human skin gene expression studies are important tools to assess active ingredient compounds such as plant extract blends to advance dermal hypotheses toward validating cosmetic formulations with botanical molecules.


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