The Role of Equilibrium between Free Radicals and Antioxidants in Depression and Bipolar Disorder

Background: Increasing evidence suggests that the presence of oxidative stress and disorders of the antioxidant defense system are involved in a wide range of neuropsychiatric disorders, such as bipolar disorder, schizophrenia and major depression, but the exact mechanism remains unknown. This review focuses on a better appreciation of the contribution of oxidative stress to depression and bipolar disorder. Methods: This review was conducted by extracting information from other research and review studies, as well as other meta-analyses, using two search engines, PubMed and Google Scholar. Results: As far as depression is concerned, there is agreement among researchers on the association between oxidative stress and antioxidants. In bipolar disorder, however, most of them observe strong lipid peroxidation in patients, while regarding antioxidant levels, opinions are divided. Nevertheless, in recent years, it seems that on depression, there are mainly meta-analyses and reviews, rather than research studies, unlike on bipolar disorder. Conclusions: Undoubtedly, this review shows that there is an association among oxidative stress, free radicals and antioxidants in both mental disorders, but further research should be performed on the exact role of oxidative stress in the pathophysiology of these diseases.

A Preliminary Study about the Role of Reactive Oxygen Species and Inflammatory Process after COVID-19 Vaccination and COVID-19 Disease

During the last couple of critical years, worldwide, there have been more than 550 million confirmed cases of COVID-19, including more than 6 million deaths (reported by the WHO); with respect to these cases, several vaccines, mainly mRNA vaccines, seem to prevent and protect from SARS-CoV-2 infection. We hypothesize that oxidative stress is one of the key factors playing an important role in both the generation and development of various kinds of disease, as well as antibody generation, as many biological paths can generate reactive oxygen species (ROS), and cellular activities can be modulated when ROS/antioxidant balance is interrupted. A pilot study was conducted in two stages during the COVID-19 pandemic in 2021 involving 222 participants between the ages of 26 and 66 years. ROS levels were measured before an after vaccination in the blood samples of 20 individuals who were vaccinated with two doses of mRNA vaccine, and an increase in ROS levels was observed after the first dose, with no modifications observed until the day before the second vaccination dose. A statistically significant difference (p < 0.001) was observed between time points 3 and 4 (before and after second dose), when participants were vaccinated for the second time, and ROS levels decreased from 21,758 to 17,580 a.u. In the second stage, blood was collected from 28 participants 45 days after COVID-19 infection (Group A), from 131 participants 45 days after receiving two doses of mRNA vaccine against COVID-19 (Group B), and from 13 healthy individuals as a control group (Group C). Additionally, antibodies levels were measured in all groups to investigate a possible correlation with ROS levels. A strong negative correlation was found between free radicals and disease antibodies in Group A (r = −0.45, p = 0.001), especially in the male subgroup (r = −0.88, p = 0.001), as well as in the female subgroup (r = −0.24, p < 0.001). Furthermore, no significant correlation (only a negative trend) was found with antibodies derived from vaccination in Group B (r = −0.01), and a negative trend was observed in the female subgroup, whereas a positive trend was observed in the male subgroup.

DNA Methylation Is Correlated with Oxidative Stress in Myelodysplastic Syndrome-Relevance as Complementary Prognostic Biomarkers

Simple Summary

Myelodysplastic syndrome (MDS) is a hematological malignancy with a high propensity to evolve to acute myeloid leukemia. Oxidative stress and abnormal DNA methylation are important in this neoplasia’s development and progression. We investigate whether oxidative stress parameters were correlated with localized and global DNA methylations in the peripheral blood of patients with MDS. We found that oxidative stress was positively correlated with DNA methylation and associated with worse overall survival. Biologically, these facts suggest a relationship between oxidative stress and DNA methylation, two common pathogenic mechanisms involved in MDS. Clinically, our findings can improve an MDS patient’s management if used as complementary prognostic biomarkers.

Abstract

Oxidative stress and abnormal DNA methylation have been implicated in cancer, including myelodysplastic syndromes (MDSs). This fact leads us to investigate whether oxidative stress is correlated with localized and global DNA methylations in the peripheral blood of MDS patients. Sixty-six MDS patients and 26 healthy individuals were analyzed. Several oxidative stress and macromolecule damage parameters were analyzed. Localized (gene promotor) and global DNA methylations (5-mC and 5-hmC levels; LINE-1 methylation) were assessed. MDS patients had lower levels of reduced glutathione and total antioxidant status (TAS) and higher levels of peroxides, nitric oxide, peroxides/TAS, and 8-hydroxy-2-deoxyguanosine compared with controls. These patients had higher 5-mC levels and lower 5-hmC/5-mC ratio and LINE-1 methylation and increased methylation frequency of at least one methylated gene. Peroxide levels and peroxide/TAS ratio were higher in patients with methylated genes than those without methylation and negatively correlated with LINE-1 methylation and positively with 5-mC levels. The 5-hmC/5-mC ratio was significantly associated with progression to acute leukemia and peroxide/TAS ratio with overall survival. This study points to a relationship between oxidative stress and DNA methylation, two common pathogenic mechanisms involved in MDS, and suggests the relevance of 5-hmC/5-mC and peroxide/TAS ratios as complementary prognostic biomarkers.

Increased Oxidative Stress in Acute Myeloid Leukemia Patients after Red Blood Cell Transfusion, but Not Platelet Transfusion, Results Mainly from the Oxidative/Nitrative Protein Damage: An Exploratory Study

Chronic oxidative stress (OS) can be an important factor of acute myeloid leukemia (AML) progression; however, there are no data on the extent/consequence of OS after transfusion of packed red blood cells (pRBCs) and platelet concentrates (PCs), which are commonly used in the treatment of leukemia-associated anemia and thrombocytopenia. We aimed to investigate the effects of pRBC/PC transfusion on the OS markers, i.e., thiol and carbonyl (CO) groups, 3-nitrotyrosine (3-NT), thiobarbituric acid reactive substances (TBARS), advanced glycation end products (AGE), total antioxidant capacity (TAC), SOD, GST, and LDH, in the blood plasma of AML patients, before and 24 h post-transfusion. In this exploratory study, 52 patients were examined, of which 27 were transfused with pRBCs and 25 with PCs. Age-matched healthy subjects were also enrolled as controls. Our results showed the oxidation of thiols, increased 3-NT, AGE levels, and decreased TAC in AML groups versus controls. After pRBC transfusion, CO groups, AGE, and 3-NT significantly increased (by approximately 30, 23, and 35%; p < 0.05, p < 0.05, and p < 0.01, respectively) while thiols reduced (by 18%; p < 0.05). The PC transfusion resulted in the raise of TBARS and AGE (by 45%; p < 0.01 and 31%; p < 0.001), respectively). Other variables showed no significant post-transfusion changes. In conclusion, transfusion of both pRBCs and PCs was associated with an increased OS; however, transfusing the former may have more severe consequences, since it is associated with the irreversible oxidative/nitrative modifications of plasma proteins.

Synthesis, Structural Studies, and α-Glucosidase Inhibitory, Antidiabetic, and Antioxidant Activities of 2,3-Dihydroquinazolin-4(1H)-ones Derived from Pyrazol-4-carbaldehyde and Anilines

A series of new quinazoline derivatives were designed and synthesized via a one-pot condensation reaction between isatoic anhydride and aromatic aldehydes with anilines using aluminum sulfate as a catalyst in refluxing ethanol. Their structures were confirmed by their physical, IR, 1H NMR, 13C NMR, and mass spectroscopy data and evaluated for some biological effects, including the antioxidant and α-glucosidase inhibitory activities as well as some in vivo hematological parameters. The ability of synthesized compounds in the inhibition of α-glucosidase was also investigated through the in silico study. The significant and important changes in some hematological tests were perceived. Notably, compound 4h showed more reducing effects on cholesterol and triglyceride levels. This molecule certainly has the potential to be developed as the antihyperlipemic compound. The tested compounds, in particular, compounds 4j and 4l, were found to be uniquely reducing blood sugar levels. The entire synthesized compounds showed the potent α-glucosidase inhibitory activity compared with acarbose as a standard material. Amongst, the compounds 4h and 4i showed the strongest enzyme inhibitory potentials than the standard drug acarbose. There was a good correlation between in vitro and in silico studies for ligands 4i and 4l. The majority of compounds presented a good radical scavenging activity, though the compound 4j exhibited the strongest activity, even to the standard of ascorbic acid. Further studies are required to determine whether these main compounds could be a potential treatment for diabetes and hyperlipidemia diseases.