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-1ß 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.

Contribution of Attenuation of TNF-α and NF-κB in the Anti-Epileptic, Anti-Apoptotic and Neuroprotective Potential of Rosa webbiana Fruit and Its Chitosan Encapsulation.

Rosa webbiana L. (Rosaceae) is one of the least reported and most understudied members of this family. It is native to the Himalayan regions of Pakistan and Nepal. The anti-convulsant effect of n-hexane extract of fruit of Rosa webbiana was investigated in a pentylenetetrazole (PTZ)-induced animal model of epilepsy. Male Sprague-Dawley rats were divided into six groups (n = 7) including control, PTZ (40 mg/kg), diazepam (4 mg/kg) and n-hexane extract (at 50, 150 and 300 mg/kg). Convulsive behavior was observed and resultant seizures were scored, animals sacrificed and their brains preserved. Chitosan nanoparticles were prepared using the ionic gelation method and characterized by UV-analysis, zeta potential and Fourier transform infrared spectroscopy (FTIR). The effects of all the treatments on the expression of phosphorylated cytokine tumor necrosis factor α (p-TNF-α) and phosphorylated transcription factor nuclear factor kappa B (p-NF-κB) expression in the cortex and hippocampus of the brains of treated rats were studied through enzyme linked immunosorbent assay (ELISA) and morphological differences and surviving neuronal number were recorded through hematoxylene and eosin (H&E) staining. Significant changes in seizures score and survival rate of rats were observed. Downregulation of neuro-inflammation, p-TNF-α and p-NF-κB was evident. Gas Chromatography-Mass Spectrometry (GC-MS) analysis of this fraction showed multiple constituents of interest, including esters, alkanes and amines.

Association of Alzheimer's Disease with Genetic Variants of Apolipoprotein E, Clusterin, TNF-α, and IL-6 Among Elderly Saudis.

BACKGROUND: In the wake of the warning by WHO that the prevalence of dementia may have a rise of 125% in the Middle East by 2050, identification of the genetic risk factors in Arab populations is urgent. OBJECTIVES: To investigate the association of Single Nucleotide Polymorphisms (SNPs) in apolipoprotein E (ApoE), clusterin (CLU), tumor necrotic factor- α (TNF-α) and interleukin-6 (IL-6) genes, with risk of Alzheimer's disease (AD) in Saudi Arabian participants. METHODS: A total of 42 Saudi AD patients and 23 age-matched control participants were genotyped for eight SNPs: rs429358, rs7412 (ApoE); rs11136000, rs1532278 (CLU); rs1800629, rs1799724 (TNF-α) and rs1800796, rs1800795(IL-6), by RT-PCR using the TaqMan assay. Serum concentrations of amyloid beta peptide 1-40(Aß1-40), amyloid beta peptide 1-42(Aß1- 42), CLU and some other biochemical markers were measured. RESULTS: A significant increase (p=0.004) in the serum CLU level was detected in the AD group (340.4 ± 74.6) compared with control group (265.0 ± 80.9). For rs1532278 (CLU), genotype GA was significantly higher in AD patients (57.1%) than in the control participants (26.1%), [p=0.024, OR = 4.00, 95% CI (1.20-13.28)]. For the ApoE SNP rs7412, 40.4% of patients carried a TT genotype, whereas it was completely absent in the controls [p = 0.020, OR = 30.53, 95% CI (1.73 - 540.05)].For rs429358 (ApoE), patients showed a significantly increased frequency of the TC genotype [p = 0.006, OR = 9.33, 95% CI (1.89-46.19)] and TT [p = 0.045, OR = 19.76, 95% CI (1.07-366.0)] genotype than controls. AD patients with CC genotype for ApoE rs429358 had significantly lower levels of Aß1-40 (p=0.04) in AD patients than controls. Carriers of genotype GG for rs1800629 (TNF-α) showed significantly higher levels of serum IL-6 (p = 0.04) in AD patients. CONCLUSION: Genetic variants in ApoE and CLU may influence susceptibility to AD among Saudi Arabian participants.

The Effect of Local Renin Angiotensin System in the Common Types of Cancer.

The Renin Angiotensin System (RAS) is a hormonal system that is responsible for blood pressure hemostasis and electrolyte balance. It is implicated in cancer hallmarks because it is expressed locally in almost all of the body's tissues. In this review, current knowledge on the effect of local RAS in the common types of cancer such as breast, lung, liver, prostate and skin cancer is summarised. The mechanisms by which RAS components could increase or decrease cancer activity are also discussed. In addition to the former, this review explores how the administration of AT1R blockers and ACE inhibitors drugs intervene with cancer therapy and contribute to the outcomes of cancer.

Eplerenone nanocrystals engineered by controlled crystallization for enhanced oral bioavailability.

Poor aqueous solubility of eplerenone (EPL) is a major obstacle to achieve sufficient bioavailability after oral administration. In this study, we aimed to develop and evaluate eplerenone nanocrystals (EPL-NCs) for solubility and dissolution enhancement. D-optimal combined mixture process using Design-Expert software was employed to generate different combinations for optimization. EPL-NCs were prepared by a bottom-up, controlled crystallization technique during freeze-drying. The optimized EPL-NCs were evaluated for their size, morphology, thermal behavior, crystalline structure, saturation solubility, dissolution profile, in vivo pharmacokinetics, and acute toxicity. The optimized EPL-NCs showed mean particle size of 46.8 nm. Scanning electron microscopy revealed the formation of elongated parallelepiped shaped NCs. DSC and PXRD analysis confirmed the crystalline structure and the absence of any polymorphic transition in EPL-NCs. Furthermore, EPL-NCs demonstrated a 17-fold prompt increase in the saturation solubility of EPL (8.96 vs. 155.85 µg/mL). The dissolution rate was also significantly higher as indicated by ∼95% dissolution from EPL-NCs in 10 min compared to only 29% from EPL powder. EPL-NCs improved the oral bioavailability as indicated by higher AUC, Cmax, and lower Tmax than EPL powder. Acute oral toxicity study showed that EPL-NCs do not pose any toxicity concern to the blood and vital organs. Consequently, NCs prepared by controlled crystallization technique present a promising strategy to improve solubility profile, dissolution velocity and bioavailability of poorly water-soluble drugs.