4 research outputs found
Neuroprotective effect of quercetin in murine cortical brain tissue cultures
Summary: Purpose: Quercetin (QR) is bioflavonoids known for its antioxidants property and its ability to alleviate oxidative stress and promote cellular survival. The aim of this study was to explore the neuroprotective potential of QR against the induced oxidative stress. Methods: Cortical brain tissue cultures from one week old Wister rats were set up in four groups. Group 1: the control group without any treatments; Group 2: cortical cultures treated with 1 mM H2O2 for one hour; Group 3: Cortical cultures pretreated with varying doses of QR for 24 h followed by treatment with 1 mM H2O2 for 1 h; Group 4: Cortical cultures treated with the vehicle alone (DMSO). The cortical Tissues from all four groups were homogenized, both the homogenized cortical tissues and conditioned medium was used for the biochemical assay. For histology studies cortical brain tissue were fixed in 10% formalin and stained with H&E. Results: Pretreatment with 100 μg/ml showed the optimum concentration, which completely ameliorates the effect of induced oxidative stress by H2O2. All of the biochemical markers of oxidative stress such as lipid peroxidation, GST enzyme assay, DNA damage and fragmentation were completely reversed with the pretreatments of QR. Histology of the cortical tissues further confirmed the biochemical assays as it showed the pretreatments with QR resulted in the neuronal survival and viability. Conclusions: This study further reiterated the neuroprotective role of QR against oxidative stress-related neurodegenerative disorders. Keywords: Oxidative stress (OS), Quercetin (QR), Neuroprotection, Cortical brain cultures, Lipid peroxidation, DNA damag
Angiotensin II Exaggerates SARS-CoV-2 Specific T-Cell Response in Convalescent Individuals following COVID-19
Dysregulation of renin−angiotensin systems during coronavirus disease 2019 (COVID-19) infection worsens the symptoms and contributes to COVID-19 severity and mortality. This study sought to investigate the effect of exogenous angiotensin II (Ang-II) on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T-cells response in recovered COVID-19 patients. Human peripheral blood mononuclear cells (PBMCs) were treated with Ang II and then stimulated with a SARS-CoV-2 peptide pool. T-cell responses were measured using flow cytometry, while enzyme-linked immunosorbent assay (ELISA) and intracellular cytokine staining (ICS) assays determined functional capability and polarization. Additionally, the relative level of protein phosphorylation was measured using a phosphokinase array. Our results showed that Ang II treatment significantly increased the magnitude of SARS-CoV-2-specific T-cell response in stimulated PBMCs with a SARS-CoV-2 peptide pool. Moreover, the phosphorylation levels of numerous proteins implicated in cardiovascular diseases, inflammation, and viral infection showed significant increases in the presence of Ang II. The mitogenic stimulation of PBMCs after Ang II and SARS-CoV-2 peptide pool stimulation showed functional polarization of T-cells toward Th1/Th17 and Th17 phenotypes, respectively. Meanwhile, ELISA showed increased productions of IL-1β and IL-6 in Ang II-stimulated PBMCs without affecting the IL-10 level. To our knowledge, this study is the first to demonstrate that Ang II exaggerates SARS-CoV-2-specific T-cells response. Therefore, during COVID-19 infection, Ang II may aggravate the inflammatory response and change the immune response toward a more inflammatory profile against SARS-CoV-2 infection
Melatonin delivered in solid lipid nanoparticles ameliorated its neuroprotective effects in cerebral ischemia
The current study explores the potential of melatonin (MLT)-loaded solid lipid nanoparticles (MLT-SLNs) for better neuroprotective effects in ischemic stroke. MLT-SLNs were prepared using lipid matrix of palmityl alcohol with a mixture of surfactants (Tween 40, Span 40, Myrj 52) for stabilizing the lipid matrix. MLT-SLNs were tested for physical and chemical properties, thermal and polymorphic changes, in vitro drug release and in vivo neuroprotective studies in rats using permanent middle cerebral artery occlusion (p-MCAO) model. The optimized MLT-SLNs showed particle size of ∼159 nm, zeta potential of −29.6 mV and high entrapment efficiency ∼92%. Thermal and polymorphic studies showed conversion of crystalline MLT to amorphous form after its entrapment in lipid matrix. MLT-SLNs displayed a sustained release pattern compared to MLT dispersion. MLT-SLNs significantly enhanced the neuroprotective profile of MLT ascertained by reduced brain infarction, recovered behavioral responses, low expression of inflammatory markers and improved oxidation protection in rats. MLT-SLNs also showed reduced hepatotoxicity compared to p-MCAO. From these outcomes, it is evidenced that MLT-SLNs have improved neuroprotection as compared to MLT dispersion and thereby present a promising approach to deliver MLT to the brain for better therapeutic outcomes in ischemic stroke
Angiogenin Levels and Their Association with Cardiometabolic Indices Following Vitamin D Status Correction in Saudi Adults
Angiogenin (ANG), a multifunctional protein known to induce blood vessel formation, is a potential biomarker for cardiovascular diseases; however, whether it is affected by vitamin D supplementation is not known. This interventional study in vitamin D-deficient Saudi adults was designed to investigate it. A total of 100 vitamin D-deficient Saudi adults aged 30–50 years were randomly selected to undergo 6-month vitamin D supplementation. Circulating levels of fasting glucose, lipids, vitamin D, apolipoproteins (AI, AII, B, CI, CII, CIII, E, and H), and ANG were measured using commercially available assays at baseline and after six months. Overall, vitamin D levels increased significantly post intervention. With this, levels of apo-CIII and apo-E significantly increased (p-values of 0.001 and 0.009, respectively) with a significant parallel decrease in apo-B (p = 0.003). ANG levels were significantly positively associated with most apolipoproteins and inversely correlated with HDL-cholesterol. Post intervention, the changes in ANG levels were positively correlated with apo-E (r = 0.32; p p < 0.05 in males). Vitamin D supplementation may modestly affect ANG levels. The association observed between ANG and apo-E is worthy of further investigation since both biomarkers have been linked to neurodegenerative disorders