Quinolizidines as Novel SARS-CoV-2 Entry Inhibitors

COVID-19, caused by the highly transmissible severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has rapidly spread and become a pandemic since its outbreak in 2019. We have previously discovered that aloperine is a new privileged scaffold that can be modified to become a specific antiviral compound with markedly improved potency against different viruses, such as the influenza virus. In this study, we have identified a collection of aloperine derivatives that can inhibit the entry of SARS-CoV-2 into host cells. Compound 5 is the most potent tested aloperine derivative that inhibited the entry of SARS-CoV-2 (D614G variant) spike protein-pseudotyped virus with an IC50 of 0.5 µM. The compound was also active against several other SARS-CoV-2 variants including Delta and Omicron. Results of a confocal microscopy study suggest that compound 5 inhibited the viral entry before fusion to the cell or endosomal membrane. The results are consistent with the notion that aloperine is a privileged scaffold that can be used to develop potent anti-SARS-CoV-2 entry inhibitors

Thrombospondin-1 expression and modulation of Wnt and hippo signaling pathways during the early phase of Trypanosoma cruzi infection of heart endothelial cells

The protozoan parasite, Trypanosoma cruzi, causes severe morbidity and mortality in afflicted individuals. Approximately 30% of T. cruzi infected individuals present with cardiac pathology. The invasive forms of the parasite are carried in the vascular system to infect other cells of the body. During transportation, the molecular mechanisms by which the parasite signals and interact with host endothelial cells (EC) especially heart endothelium is currently unknown. The parasite increases host thrombospondin-1 (TSP1) expression and activates the Wnt/β-catenin and hippo signaling pathways during the early phase of infection. The links between TSP1 and activation of the signaling pathways and their impact on parasite infectivity during the early phase of infection remain unknown. To elucidate the significance of TSP1 function in YAP/β-catenin colocalization and how they impact parasite infectivity during the early phase of infection, we challenged mouse heart endothelial cells (MHEC) from wild type (WT) and TSP1 knockout mice with T. cruzi and evaluated Wnt signaling, YAP/β-catenin crosstalk, and how they affect parasite infection. We found that in the absence of TSP1, the parasite induced the expression of Wnt-5a to a maximum at 2 h (1.73±0.13), P\u3c 0.001 and enhanced the level of phosphorylated glycogen synthase kinase 3β at the same time point (2.99±0.24), PT. cruzi infection. Importantly, dysregulation of this crosstalk by pre-incubation of WT MHEC with a β-catenin inhibitor, endo-IWR 1, dramatically reduced the level of infection of WT MHEC. Parasite infectivity of inhibitor treated WT MHEC was similar to the level of infection of TSP1 KO MHEC. These results indicate that the β-catenin pathway induced by the parasite and regulated by TSP1 during the early phase of T. cruzi infection is an important potential therapeutic target, which can be explored for the prophylactic prevention of T. cruzi infection

Inevitable glutathione, then and now

706-716<span style="font-size: 14.5pt;mso-bidi-font-size:8.5pt;font-family:" times="" new="" roman","serif""="">Glutathione a predominant tripeptide thiol compound of many prokaryotes and eukaryotes, is synthesized from its precursor amino acids eg. γ-glutamate, cysteine and glycine. It is mainly involved in detoxication mechanisms through conjugation reactions. Other functions include thiol transfer, destruction of free radicals and metabolism of various exogenous and endogenous compounds. It becomes mandatory for a cell to manage high concentration of intracellular GSH to protect itself from chemical/dug abuse. Glutathione dependent enzymes viz: glutathione-S-transferases, glutathione peroxidase, glutathione reductase and γ -glutamate transpeptidase facilitate protective manifestations. Liver serves as a glutathione generating factor which supplies the kidney and intestine with other constituents of glutathione resynthesis. The principal mechanism of hepatocyte glutathione turnover appears to be cellular efflux. Kidney too plays an important role in organismic GSH homeostasis. Role of GSH in organs like lung, intestine and brain has recently been described. GSH involvement in programmed cell death has also been indicated. Immense interest makes the then "thee glutathione" as" inevitable glutathione". <span style="font-size:14.5pt;mso-bidi-font-size:8.5pt; line-height:115%;font-family:" times="" new="" roman","serif""="">This article describes the role of this vital molecule in cell physiology and detoxication mechanisms in particular. </span

Pierwotny nabłoniak chłonny gardła dolnego: niezwykle rzadka prezentacja pozanosogardłowa

Wstęp: 66-letni mężczyzna uskarżał się na dyskomfort gardła i ból przy przełykaniu. Wynik badania fiberoskopowego krtani był prawidłowy, natomiast podejrzenia budził obraz uzyskany z użyciem wąskiej wiązki obrazowania. Uzyskano dodatni wynik badania USG-FNAC pod kątem obecności złośliwych, przerzutowych komórek rakowych. W badaniu tomografii komputerowej szyi z kontrastem uwidoczniono zatarcie lewego zachyłka gruszkowatego do poziomu chrząstki pierścieniowatej, stykające się ze skrzydłami chrząstki tarczowatej, chrząstką nalewkowatą i mięśniami przedkręgowymi. W badaniu endoskopowym GOPP ujawniono obecność owrzodzonej masy w lewym zachyłku gruszkowatym. Badanie histopatologiczne wykazało obecność stratyfikowanej, wyścielonej niezrogowaciałym nabłonkiem płaskokomórkowym tkanki z dużymi kolistymi lub wielokątnymi komórkami nowotworowymi widocznymi w zrębie podnabłonkowym. Komórki nowotworowe były otoczone zrębem limfatycznym. W badaniu immunohistochemicznym komórki nowotworowe dały wynik dodatni dla pancytokeratyny i ujemny dla: CD45, chromograniny i synaptofizyny. Limfocyty dały wynik dodatni dla CD45. Postawiono rozpoznanie raka limfonabłonkowego. Ze względu na nieoperacyjność guza w leczeniu, zastosowano radioterapię. Wnioski: Nabłoniak chłonny jest pierwotnym guzem nosogardzieli, lecz rzadko obserwuje się go w miejscach, takich jak: gardło środkowe, krtań i gardło dolne. Do dzisiaj zgłoszono jedynie około 50 przypadków pozanosogardłowych, w tym jedynie 10–12 zlokalizowanych w gardle dolnym. Podstawą leczenia jest radioterapia, choć w przypadkach zmian miejscowych można rozważać operację chirurgiczną

Primary lymphoepithelial carcinoma of the hypopharynx: an extremely rare non-nasopharyngeal presentation

Introduction: A 66-year-old male complained of throat discomfort and odynophagia. Laryngeal fiber optic examination was normal but narrow band imaging was suspicious. USG-FNAC from a cervical lymph node was positive for malignant metastatic carcinoma cells. CECT revealed obliteration of the left pyriform fossa till the level of cricoid cartilage, abutting the ala of the thyroid cartilage, arytenoid cartilage and prevertebral muscles. UGIE revealed an ulcerated mass lesion in the left pyriform fossa. Histopathological examination revealed stratified non-keratinized squamous epithelial lined tissue with subepithelial stroma showing large round to polygonal tumour cells. The tumour cells were surrounded by a lymphoid stroma. On immunohistochemistry the tumour cells were positive for pancytokeratin and negative for CD45, chromogranin and synaptophysin. Lymphocytes were positive for CD45. The diagnosis of lymphoepithelial carcinoma was established. The tumour was inoperable and was treated by radiotherapy. Conclusions: Lymphoepithelial carcinoma is the primary entity of the nasopharynx but rarely seen at sites like oropharynx, larynx and hypopharynx. Only around 50 non-nasopharyngeal cases have been reported till date out of which only 10–12 were in the hypopharynx. Radiotherapy is the mainstay of treatment whereas surgery can be considered for a local disease

Do Progestin-Only Contraceptives Contribute to the Risk of Developing Depression as Implied by Beta-Arrestin 1 Levels in Leukocytes? A Pilot Study

We reported previously that reduction in beta-arrestin 1 (&beta;-AR 1) protein levels in peripheral blood mononuclear leukocytes (PBMC) significantly correlated with the severity of depressive symptoms in reproductive women. In this pilot study, we used &beta;-AR 1 protein levels in PBMC as a marker for developing depressive symptoms and the Hamilton Depression Rating Scale (HAM-D) scores to assess potential mood-related side effects of oral contraceptive use for routine birth control among women. We evaluated 29 women in this study. We enrolled the participants in three groups: Estrogen-progestin combination-oral contraceptives (COC, n = 10), progestin-only contraceptives (POC, n = 12), and non-hormonal or no contraceptives (NC, n = 7). We determined the &beta;-AR 1 protein levels in PBMCs by enzyme-linked immunosorbent assay (ELISA). We found that women in the POC group had significantly higher HAM-D scores compared to those in the COC (p &lt; 0.0004) and NC (p &lt; 0.004). The levels of &beta;-AR 1 protein were significantly attenuated in women in the POC group compared to women in the NC group (p = 0.03). Our findings suggest that the use of POC is a potential risk factor for developing depressive symptoms

Thrombospondin-1 expression and modulation of Wnt and hippo signaling pathways during the early phase of Trypanosoma cruzi infection of heart endothelial cells.

The protozoan parasite, Trypanosoma cruzi, causes severe morbidity and mortality in afflicted individuals. Approximately 30% of T. cruzi infected individuals present with cardiac pathology. The invasive forms of the parasite are carried in the vascular system to infect other cells of the body. During transportation, the molecular mechanisms by which the parasite signals and interact with host endothelial cells (EC) especially heart endothelium is currently unknown. The parasite increases host thrombospondin-1 (TSP1) expression and activates the Wnt/β-catenin and hippo signaling pathways during the early phase of infection. The links between TSP1 and activation of the signaling pathways and their impact on parasite infectivity during the early phase of infection remain unknown. To elucidate the significance of TSP1 function in YAP/β-catenin colocalization and how they impact parasite infectivity during the early phase of infection, we challenged mouse heart endothelial cells (MHEC) from wild type (WT) and TSP1 knockout mice with T. cruzi and evaluated Wnt signaling, YAP/β-catenin crosstalk, and how they affect parasite infection. We found that in the absence of TSP1, the parasite induced the expression of Wnt-5a to a maximum at 2 h (1.73±0.13), P< 0.001 and enhanced the level of phosphorylated glycogen synthase kinase 3β at the same time point (2.99±0.24), P<0.001. In WT MHEC, the levels of Wnt-5a were toned down and the level of p-GSK-3β was lowest at 2 h (0.47±0.06), P< 0.01 compared to uninfected control. This was accompanied by a continuous significant increase in the nuclear colocalization of β-catenin/YAP in TSP1 KO MHEC with a maximum Pearson correlation coefficient of (0.67±0.02), P< 0.05 at 6 h. In WT MHEC, the nuclear colocalization of β-catenin/YAP remained steady and showed a reduction at 6 h (0.29±0.007), P< 0.05. These results indicate that TSP1 plays an important role in regulating β-catenin/YAP colocalization during the early phase of T. cruzi infection. Importantly, dysregulation of this crosstalk by pre-incubation of WT MHEC with a β-catenin inhibitor, endo-IWR 1, dramatically reduced the level of infection of WT MHEC. Parasite infectivity of inhibitor treated WT MHEC was similar to the level of infection of TSP1 KO MHEC. These results indicate that the β-catenin pathway induced by the parasite and regulated by TSP1 during the early phase of T. cruzi infection is an important potential therapeutic target, which can be explored for the prophylactic prevention of T. cruzi infection