Characteristics of resveratrol and serotonin on antioxidant capacity and susceptibility to oxidation of red blood cells in stored human blood in a time-dependent manner

Extracellular vesicles: effectors of transfusion-related acute lung injury

Respiratory transfusion reactions represent some of the most severe adverse reactions related to receiving blood products. Of those, transfusion-related acute lung injury (TRALI) is associated with elevated morbidity and mortality. TRALI is characterized by severe lung injury associated with inflammation, pulmonary neutrophil infiltration, lung barrier leak, and increased interstitial and airspace edema that cause respiratory failure. Presently, there are few means of detecting TRALI beyond clinical definitions based on physical examination and vital signs or preventing/treating TRALI beyond supportive care with oxygen and positive pressure ventilation. Mechanistically, TRALI is thought to be mediated by the culmination of two successive proinflammatory hits, which typically comprise a recipient factor (1st hit-e.g., systemic inflammatory conditions) and a donor factor (2nd hit-e.g., blood products containing pathogenic antibodies or bioactive lipids). An emerging concept in TRALI research is the contribution of extracellular vesicles (EVs) in mediating the first and/or second hit in TRALI. EVs are small, subcellular, membrane-bound vesicles that circulate in donor and recipient blood. Injurious EVs may be released by immune or vascular cells during inflammation, by infectious bacteria, or in blood products during storage, and can target the lung upon systemic dissemination. This review assesses emerging concepts such as how EVs: 1) mediate TRALI, 2) represent targets for therapeutic intervention to prevent or treat TRALI, and 3) serve as biochemical biomarkers facilitating TRALI diagnosis and detection in at-risk patients.

Red Blood Cell Metabolism In Vivo and In Vitro

Red blood cells (RBC) are the most abundant cell in the human body, with a central role in oxygen transport and its delivery to tissues. However, omics technologies recently revealed the unanticipated complexity of the RBC proteome and metabolome, paving the way for a reinterpretation of the mechanisms by which RBC metabolism regulates systems biology beyond oxygen transport. The new data and analytical tools also informed the dissection of the changes that RBCs undergo during refrigerated storage under blood bank conditions, a logistic necessity that makes >100 million units available for life-saving transfusions every year worldwide. In this narrative review, we summarize the last decade of advances in the field of RBC metabolism in vivo and in the blood bank in vitro, a narrative largely influenced by the authors' own journeys in this field. We hope that this review will stimulate further research in this interesting and medically important area or, at least, serve as a testament to our fascination with this simple, yet complex, cell.

The levels of nitrite, nitrate and lipid peroxidation in diabetic mouse brain: the effect of melatonin and pentoxifylline

OBJECTIVE

This study investigated the relationship between diabetes (DM) and nitrite, nitrate and MDA levels and effect of melatonin and pentoxifylline.

METHODS

Sixty mice were randomly divided into four groups. Control: no action; Diabetes group (DM): after fasting-blood-glucose (FBG) was measured, 150 mg/kg alloxane was applied intraperitoneally three-times every other day; Diabetes + Melatonin (DM + MLT) and Diabetes + Pentoxifylline groups (DM + PTX): following the same procedures with DM, 10 mg/kg melatonin and 50 mg/kg pentoxifylline were administered subcutaneously six days, respectively. Following FBG analysis, brain tissues were taken under the anaesthesia. Nitrite, nitrate and MDA levels were measured.

RESULTS

In the all groups with alloxane, FBG were higher than in before application (p < .05). Also, FBG, nitrite, nitrate and MDA levels in the DM + MLT and DM + PTX groups were lower than in the DM (p < .05).

CONCLUSIONS

Nitrite and nitrate may be related to etiopathogenesis of DM, and pentoxifylline and especially melatonin relatively decrease nitrite, nitrate and lipid peroxidation.

Forecasting of Oxidant/Antioxidant levels of COVID-19 patients by using Expert models with biomarkers used in the Diagnosis/Prognosis of COVID-19

Background

Early detection of oxidant-antioxidant levels and special care in severe patients are important in combating the COVID-19 epidemic. However, this process is costly and time consuming. Therefore, there is a need for faster, reliable and economical methods.

Methods

In this study, antioxidant/oxidant levels of patients were estimated by Expert-models using biomarkers, which are effective in the diagnosis/prognosis of COVID-19 disease. For this purpose, Expert-models were trained and created between the white-blood-cell-count (WBC), lymphocyte-count (LYM), C-reactive-protein (CRP), D-dimer, ferritin values of 35 patients with COVID-19 and antioxidant/oxidant parameter values of the same patients. Error criteria and R² ratio were taken into account for the performance of the models. The validity of the all models was checked by the Box-Jenkis-method.

Results

Antioxidant/Oxidant levels were estimated with 95% confidence-coefficient using the values of WBC, LYM, CRP, D-dimer, ferritin of different 500 patients diagnosed with COVID-19 with the trained models. The error rate of all models was low and the coefficients of determination were sufficient. In the first data set, there was no significant difference between measured antioxidant/oxidant levels and predicted antioxidant/oxidant levels. This result showed that the models are accurate and reliable. In determining antioxidant/oxidant levels, LYM and ferritin biomarkers had the most effect on models, while WBC and CRP biomarkers had the least effect. The antioxidant/oxidant parameter estimated with the highest accuracy was Native-Thiol divided by Total-Thiol.

Conclusions

The results showed that the antioxidant/oxidant levels of infected patients can be estimated accurately and reliably with LYM, ferritin, D-dimer, WBC, CRP biomarkers in the COVID-19 outbreak.

In Vivo Screening and Antidiabetic Potential of Polyphenol Extracts from Guava Pulp, Seeds and Leaves

Simple Summary

The incidence of diabetes has risen from 151 million people in 2000 to 463 million in 2019, with 4.2 million estimated deaths in 2019, and over 700 million people will be affected with diabetes worldwide by 2045. Thus, the screening of anti-diabetic plants is inevitable in order to overcome diabetes. This study has investigated the anti-diabetic potential of polyphenol extracts from guava leaves, seeds and pulp using an albino rat model. The in vivo study has reported that polyphenols from leaves and pulp have an ability to improve diabetic parameters, such as insulin, blood glucose and triglycerides levels. The improvement in blood parameters is also an indication of these extracts that are valuable for diabetes management. The findings of this study reveal that polyphenols from guava leaves, pulp and seeds can be used for drug development.

Abstract

The present study investigates the antidiabetic potential of polyphenol extracts purified from guava pulp, seeds and leaves using an in vivo experiment on albino rats. The polyphenols from guava pulp, seeds and leaves were extracted using methanol solvent and the sonication method while being evaluated by total phenolic contents and radical scavenging activity assay. The proximate composition of powders revealed that ash, protein and total sugars were significantly (p < 0.05) higher in leaves and seeds, while vitamin C was highest in pulp. Total phenolic and antioxidant activities were highest in pulp followed by leaves and seeds. The findings of feed intake and body gain revealed that the supplementation of polyphenols, especially from pulp, significantly (p < 0.05) increased the feed intake, which resulted in increased body weight. Moreover, total cholesterol (TC) and low-density lipoprotein (LDL) levels were significantly (p < 0.05) decreased, while the level of high-density lipoprotein (HDL) was increased in groups fed with polyphenols from guava pulp compared to both (+ive and –ive) control groups. Furthermore, blood glucose and triglycerides were significantly (p < 0.05) decreased in supplemented groups compared to the control group of diabetes mice, which resulted in the inhibition of α-amylase and glucose transport. Besides this, packed cell volume (PCV), mean corpuscular volume (MCV), hemoglobin, red blood cells (RBCs), white blood cells (WBCs) and platelet levels were increased significantly (p < 0.05) in pulp’s extract followed by leaves and seeds compared to both control groups. Overall, the antidiabetic potential of different extracts was in the following order: pulp > leaves > seeds. The findings suggest the feasibility of adding 200–250 mg/kg.bw of polyphenol extracts of pulp as an alternative to diabetic drugs.

Effects of L-carnitine on the erythrocytes of stored human blood

OBJECTIVES

This study aimed to assess the effects of L-carnitine on oxidative stress in human erythrocytes during storage.

BACKGROUND

Using antioxidants as components of blood storage solutions may combat the effects of storage-induced oxidative stress on erythrocytes.

METHODS

Blood from male adults was stored at 4 °C for 55 days in citrate phosphate dextrose adenine solution, without L-carnitine (Control) and with L-carnitine as an additive (at concentrations of 10, 30 and 60 mM - Experiments). Every fifth day, erythrocyte markers (morphology, count, haemoglobin, haemolysis and osmotic fragility), antioxidant defences (antioxidant enzymes and total antioxidant capacity) and oxidative stress markers (superoxides, lipid peroxidation and protein oxidation products) were analysed.

RESULTS

Oxidative damage was observed in controls (day 25 onwards) and in experiments (day 35 onwards). L-carnitine (10 and 30 mM) protected erythrocytes from damage up to day 35 by maintaining haemoglobin and lipid peroxidation, assisting antioxidant enzymes and increasing antioxidant capacity by elevating sulfhydryls and ascorbic acid. L-carnitine was beneficial in prolonging storage up to 55 days but could not prevent oxidative damage completely in terms of haemolysis and osmotic fragility.

CONCLUSIONS

L-carnitine ameliorated oxidative stress, but combinations with other antioxidants may provide comprehensive protection to erythrocytes during storage.

Influence of some β-lactam drugs on selected antioxidant enzyme and lipid peroxidation levels in different rat tissues

Antioxidant enzymes play an important role in body defense and free radical removal. Cephalosporins are β-lactam antibiotics. In this work, the effects of cefazolin, cefuroxime and cefoperazone which are cephalosporins on some selected antioxidant enzyme and levels of malondialdehyde (MDA) as lipid peroxidation product were investigated in kidney, liver, and brain tissues of albino female rats. Ninety-six albino rats were randomly divided into 16 groups of equal number (n = 6). 50 mg/kg cefazolin, 25 mg/kg cefuroxime, and 100 mg/kg cefoperazone were injected intraperitoneally to the groups (5th-8th and 9th-12th, and 13th-16th groups), respectively. The changes in glutathione reductase (GR), glutathione S-transferase (GST), superoxide dismutase (SOD), peroxidase (POD), and glutathione peroxidase (GSH-Px) levels were studied in each time point group and a time-dependent manner (at the 1st, 3rd, 5th and 7th hour). In addition, MDA levels were examined in all the tissues. The drugs evaluated in this study had different effects on the same enzyme in different tissues depending on time. MDA levels especially in cefazolin and cefoperazone experiments were lower in all the tissues; however, MDA levels were higher in brain and kidney tissues in the cefuroxime groups in a time-dependent manner (p < 0.05). These results revealed the complex effects of the tested drugs on different tissues at different time points. Therefore, the dose and use of these drugs should be adjusted correctly.