Fatty Acids Derived from Royal Jelly Are Modulators of Estrogen Receptor Functions

Royal jelly (RJ) excreted by honeybees and used as a nutritional and medicinal agent has estrogen-like effects, yet the compounds mediating these effects remain unidentified. The possible effects of three RJ fatty acids (FAs) (10-hydroxy-2-decenoic-10H2DA, 3,10-dihydroxydecanoic-3,10DDA, sebacic acid-SA) on estrogen signaling was investigated in various cellular systems. In MCF-7 cells, FAs, in absence of estradiol (E2), modulated the estrogen receptor (ER) recruitment to the pS2 promoter and pS2 mRNA levels via only ERβ but not ERα, while in presence of E2 FAs modulated both ERβ and ERα. Moreover, in presence of FAs, the E2-induced recruitment of the EAB1 co-activator peptide to ERα is masked and the E2-induced estrogen response element (ERE)-mediated transactivation is inhibited. In HeLa cells, in absence of E2, FAs inhibited the ERE-mediated transactivation by ERβ but not ERα, while in presence of E2, FAs inhibited ERE-activity by both ERβ and ERα. Molecular modeling revealed favorable binding of FAs to ERα at the co-activator-binding site, while binding assays showed that FAs did not bind to the ligand-binding pocket of ERα or ERβ. In KS483 osteoblasts, FAs, like E2, induced mineralization via an ER-dependent way. Our data propose a possible molecular mechanism for the estrogenic activities of RJ's components which, although structurally entirely different from E2, mediate estrogen signaling, at least in part, by modulating the recruitment of ERα, ERβ and co-activators to target genes

Immunomodulators for immunocompromised patients hospitalized for COVID-19: a meta-analysis of randomized controlled trials

BACKGROUND: Although immunomodulators have established benefit against the new coronavirus disease (COVID-19) in general, it is uncertain whether such agents improve outcomes without increasing the risk of secondary infections in the specific subgroup of previously immunocompromised patients. We assessed the effect of immunomodulators on outcomes of immunocompromised patients hospitalized for COVID-19.METHODS: The protocol was prospectively registered with PROSPERO (CRD42022335397). MEDLINE, Cochrane Central Register of Controlled Trials and references of relevant articles were searched up to 01-06-2022. Authors of potentially eligible randomized controlled trials were contacted to provide data on immunocompromised patients randomized to immunomodulators vs control (i.e., placebo or standard-of-care).FINDINGS: Eleven randomized controlled trials involving 397 immunocompromised patients hospitalized for COVID-19 were included. Ten trials had low risk of bias. There was no difference between immunocompromised patients randomized to immunomodulators vs control regarding mortality [30/182 (16.5%) vs 41/215 (19.1%); RR 0.93, 95% CI 0.61-1.41; p = 0.74], secondary infections (RR 1.00, 95% CI 0.64-1.58; p = 0.99) and change in World Health Organization ordinal scale from baseline to day 15 (weighed mean difference 0.27, 95% CI -0.09-0.63; p = 0.15). In subgroup analyses including only patients with hematologic malignancy, only trials with low risk of bias, only trials administering IL-6 inhibitors, or only trials administering immunosuppressants, there was no difference between comparators regarding mortality.INTERPRETATION: Immunomodulators, compared to control, were not associated with harmful or beneficial outcomes, including mortality, secondary infections, and change in ordinal scale, when administered to immunocompromised patients hospitalized for COVID-19.FUNDING: Hellenic Foundation for Research and Innovation.</p

Plitidepsin: Mechanisms and Clinical Profile of a Promising Antiviral Agent against COVID-19

Current standard treatment of COVID-19 lacks in effective antiviral options. Plitidepsin, a cyclic depsipeptide authorized in Australia for patients with refractory multiple myeloma, has recently emerged as a candidate anti-SARS-CoV-2 agent. The aim of this review was to summarize current knowledge on plitidepsin’s clinical profile, anti-tumour and anti-SARS-CoV-2 mechanisms and correlate this with available or anticipated, preclinical or clinical evidence on the drug’s potential for COVID-19 treatment.PubMed, Scopus, CENTRAL, clinicaltrials.gov, medRxiv and bioRxiv databases were searched.Plitidepsinexerts its anti-tumour and antiviral properties primarily through acting on isoforms of the host cell’s eukaryotic-translation-elongation-factor-1-alpha (eEF1A). Through inhibiting eEF1A and therefore translation of necessary viral proteins, it behaves as a “host-directed” anti-SARS-CoV-2 agent. In respect to its potent anti-SARS-CoV-2 properties, the drug has demonstrated superior ex vivo efficacy compared to other host-directed agents and remdesivir, and it might retain its antiviral effect against the more transmittable B.1.1.7 variant. Its well-studied safety profile, also in combination with dexamethasone, may accelerate its repurposing chances for COVID-19 treatment. Preliminary findings in hospitalized COVID-19 patients, have suggested potential safety and efficacy of plitidepsin, in terms of viral load reduction and clinical resolution. However, the still incomplete understanding of its exact integration into host cell–SARS-CoV-2 interactions, its intravenous administration exclusively purposing it for hospital settings the and precocity of clinical data are currently considered its chief deficits. A phase III trial is being planned to compare the plitidepsin–dexamethasone regimen to the current standard of care only in moderately affected hospitalized patients. Despite plitidepsin’s preclinical efficacy, current clinical evidence is inadequate for its registration in COVID-19 patients.Therefore, multicentre trials on the drug’s efficacy, potentially also studying populations of emerging SARS-CoV-2 lineages, are warranted

Plitidepsin: Mechanisms and Clinical Profile of a Promising Antiviral Agent against COVID-19

Current standard treatment of COVID-19 lacks in effective antiviral options. Plitidepsin, a cyclic depsipeptide authorized in Australia for patients with refractory multiple myeloma, has recently emerged as a candidate anti-SARS-CoV-2 agent. The aim of this review was to summarize current knowledge on plitidepsin’s clinical profile, anti-tumour and anti-SARS-CoV-2 mechanisms and correlate this with available or anticipated, preclinical or clinical evidence on the drug’s potential for COVID-19 treatment.PubMed, Scopus, CENTRAL, clinicaltrials.gov, medRxiv and bioRxiv databases were searched.Plitidepsinexerts its anti-tumour and antiviral properties primarily through acting on isoforms of the host cell’s eukaryotic-translation-elongation-factor-1-alpha (eEF1A). Through inhibiting eEF1A and therefore translation of necessary viral proteins, it behaves as a “host-directed” anti-SARS-CoV-2 agent. In respect to its potent anti-SARS-CoV-2 properties, the drug has demon-strated superior ex vivo efficacy compared to other host-directed agents and remdesivir, and it might retain its antiviral effect against the more transmittable B.1.1.7 variant. Its well-studied safety profile, also in combination with dexamethasone, may accelerate its repurposing chances for COVID-19 treatment. Preliminary findings in hospitalized COVID-19 patients, have suggested potential safety and efficacy of plitidepsin, in terms of viral load reduction and clinical resolution. However, the still incomplete understanding of its exact integration into host cell-SARS-CoV-2 interactions, its intravenous administration exclusively purposing it for hospital settings the and precocity of clinical data are currently considered its chief deficits. A phase III trial is being planned to compare the plitidepsin-dexamethasone regimen to the current standard of care only in moderately affected hospitalized patients. Despite plitidepsin’s preclinical efficacy, current clinical evidence is inadequate for its registration in COVID-19 patients.Therefore, multicentre trials on the drug’s efficacy, potentially also studying populations of emerging SARS-CoV-2 lineages, are warranted

Senescence in HBV-, HCV- and NAFLD- Mediated Hepatocellular Carcinoma and Senotherapeutics: Current Evidence and Future Perspective

Simple Summary Recent scientific discoveries identify cell senescence as pivotal in hepatocellular cancer (HCC) biology. Specifically, hepatitis B virus (HBV), hepatitis C virus (HCV) and non-alcoholic fatty liver disease (NAFLD) are major risk factors for HCC occurrence and it seems that cell senescence serves as a mediator. Furthermore, senescence is also implicated in HCC therapy resistance. Therefore, understanding and harnessing senescence (via senotherapeutics) seems highly important towards the discovery of new preventative and treatment strategies. Herein, we review the role of cell senescence in HBV-, HCV- and NAFLD- mediated HCC, and also explore the possible place of senotherapeutics in the management of HCC. By shining the spotlight on senescence-mediated HCC, we aim to inspire future research towards this rapidly evolving and highly promising field. Cell senescence constitutes a physiological process that serves as protection from malignant transformation of cells. However, recent scientific discoveries also identify cell senescence as pivotal in hepatocellular cancer (HCC) biology. The review herein aimed to accumulate evidence on senescence as a mediator of HCC occurrence in hepatitis B (HBV), C (HCV) virus infections, and non-alcoholic fatty liver disease (NAFLD). In HBV infection, the carcinogenic HBV X protein frequently mutates during chronic infection, and subsequently exhibits different effects on senescence. In HCV infection, senescent non-functional T-cells do not effectively clear pre-malignant hepatocytes. Furthermore, the HCV Core protein inhibits the occurrence of normal stress-induced hepatocyte senescence, allowing damaged cells to maintain their proliferative potential. In NAFLD-mediated HCC, current data point towards the gut microbiome and hepatic stellate cell senescence. Additionally, senescence contributes in the development of resistance in targeted therapies, such as sorafenib. Finally, the promising role of senotherapeutics in HCC was also explored. Overall, although we may still be at a primitive stage in fully unraveling the role of senescence in cancer, it seems that understanding and harnessing senescence may have the potential to revolutionize the way we treat hepatocellular cancer