Melatonin Attenuates LPS-Induced Acute Depressive-Like Behaviors and Microglial NLRP3 Inflammasome Activation Through the SIRT1/Nrf2 Pathway.

peer reviewedInflammation is a crucial component of various stress-induced responses that contributes to the pathogenesis of major depressive disorder (MDD). Depressive-like behavior (DLB) is characterized by decreased mobility and depressive behavior that occurs in systemic infection induced by Lipopolysaccharide (LPS) in experimental animals and is considered as a model of exacerbation of MDD. We assessed the effects of melatonin on behavioral changes and inflammatory cytokine expression in hippocampus of mice in LPS-induced DLB, as well as its effects on NLR Family Pyrin Domain Containing 3 (NLRP3) inflammasome activation, oxidative stress and pyroptotic cell death in murine microglia in vitro. Intraperitoneal 5 mg/kg dose of LPS was used to mimic depressive-like behaviors and melatonin was given at a dose of 500 mg/kg for 4 times with 6 h intervals, starting at 2 h before LPS administration. Behavioral assessment was carried out at 24 h post-LPS injection by tail suspension and forced swimming tests. Additionally, hippocampal cytokine and NLRP3 protein levels were estimated. Melatonin increased mobility time of LPS-induced DLB mice and suppressed NLRP3 expression and interleukin-1β (IL-1β) cleavage in the hippocampus. Immunofluorescence staining of hippocampal tissue showed that NLRP3 is mainly expressed in ionized calcium-binding adapter molecule 1 (Iba1) -positive microglia. Our results show that melatonin prevents LPS and Adenosine triphosphate (ATP) induced NLRP3 inflammasome activation in murine microglia in vitro, evidenced by inhibition of NLRP3 expression, Apoptosis-associated speck-like protein containing a CARD (ASC) speck formation, caspase-1 cleavage and interleukin-1β (IL-1β) maturation and secretion. Additionally, melatonin inhibits pyroptosis, production of mitochondrial and cytosolic reactive oxygen species (ROS) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling. The beneficial effects of melatonin on NLRP3 inflammasome activation were associated with nuclear factor erythroid 2-related factor 2 (Nrf2) and Silent information regulator 2 homolog 1 (SIRT1) activation, which were reversed by Nrf2 siRNA and SIRT1 inhibitor treatment

Ulrich bundles on Veronese surfaces

We prove that every Ulrich bundle on the Veronese surface has a resolution in terms of twists of the trivial bundle over $\mathbb{P}^{2}$. Using this classification, we prove existence results for stable Ulrich bundles over $\mathbb{P}^{k}$ with respect to an arbitrary polarization $dH$.Comment: to appear in the Proceedings of the AM

The Electrophoretic Contribution to the Solutions of Taxonomical Problems of Some Lathyrus L. Taxa Growing in Turkey

Background: The seed proteins are used as molecular markers to clarify the systematic problems. Also, electrophoretic techniques are safe tools to identify the seed proteins. In present study, it was used the SDS-PAGE technique to solve the taxonomical problems of eight taxa of genus Lathyrus belong to three sections Orobus, Lathyrostylis and Pratensis according to the globulin B and glutelin

The understanding of the immunopathology in COVID-19 infection.

Coronaviruses belonging to the Coronaviridae family are single-stranded RNA viruses. The entry of SARS-CoV-2 is accomplished via ACE-2 receptors. SARS-CoV-2 infection coactivates both innate and adaptive immune responses. Although SARS-CoV-2 stimulates antibody production with a typical pattern of IgM/IgG, cellular immunity is also impaired. In severe cases, low CD4 + and CD8 + T cell counts are associated with impaired immune functions, and high neutrophil/lymphocyte ratios accompanying low lymphocyte subsets have been demonstrated. Recently, high IFN -alpha/gamma ratios with impaired T cell responses, and increased IL-1, IL-6, TNF-alpha, MCP-1, IP-10, IL-4, IL-10 have been reported in COVID-19 infection. Increased proinflammatory cytokines and chemokines in patients with severe COVID-19 may cause the suppression of CD4 + and CD8 + T cells and regulatory T cells, causing excessive inflammatory responses and fatal cytokine storm with tissue and organ damage. Consequently, novel therapeutics to be developed against host immune system, including blockade of cytokines (IL-6, IL-1, IFN) themselves, their receptors or signaling pathways- JAK inhibitors- could be effective as potential therapeutics

Performance Evaluation of Sysmex CN-3000 and Stago STA R Max Coagulation Analyzers and Interference of Hemolysis

Background: In this study, our purpose was to evaluate the analytical performances of the STA R Max and CN-3000, and compare the results of both for PT, aPTT, fibrinogen, D-dimer, and factor VIII, and also to show the influence of hemolysis on PT, aPTT, and fibrinogen assays. Methods: Three hundred ninety-five randomly-selected blood samples from residual material from Istanbul Fac-ulty of Medicine, Central Laboratory workflow comprised the study group. PT, aPTT, fibrinogen, D-dimer, and factor VIII activity were done using both analyzers. Analytical performances were determined through precision, linearity, and comparability studies. Artificial hemolysis was performed through freezing-thawing and mechani-cal-sheer methods. Results: Intra-assay and between-day CVs% of PT and aPTT were lower than 5% for STA R Max and CN-3000. Only the within-run and between-day CVs% of fibrinogen and the between-day CVs% of D-dimer were higher than 5%, but in acceptable targets. Intra-assay and between-day CVs% of FVIII on the CN-3000 were 3.5% and 12.3% at the low and 2.5% and 5.3% at high level, and 1.8% and 3.7% at the low and 6.3% and 5.9% at high level on the STA R Max. The comparison results of PT, aPTT, fibrinogen, and D-dimer were good (r > 0.91), also good correlations were obtained for FVIII activity > 40 IU/dL and FVIII between 5 -40 IU/dL (r = 0.89). The results of the hemolysis study were within acceptable limits of the recommended criteria of Fraser and the manu-facturer. Conclusions: CN-3000 and STA R Max coagulation analyzers are accurate and highly precise systems for safe use in clinical diagnostic applications. The interferences obtained for both analyzers were found to be within accepted targets. (Clin. Lab. 2022;68:xx-xx. DOI: 10.7754/Clin.Lab.2021.210501

The Role of Melatonin on NLRP3 Inflammasome Activation in Diseases

NLRP3 inflammasome is a part of the innate immune system and responsible for the rapid identification and eradication of pathogenic microbes, metabolic stress products, reactive oxygen species, and other exogenous agents. NLRP3 inflammasome is overactivated in several neurodegenerative, cardiac, pulmonary, and metabolic diseases. Therefore, suppression of inflammasome activation is of utmost clinical importance. Melatonin is a ubiquitous hormone mainly produced in the pineal gland with circadian rhythm regulatory, antioxidant, and immunomodulatory functions. Melatonin is a natural product and safer than most chemicals to use for medicinal purposes. Many in vitro and in vivo studies have proved that melatonin alleviates NLRP3 inflammasome activity via various intracellular signaling pathways. In this review, the effect of melatonin on the NLRP3 inflammasome in the context of diseases will be discussed