Alzheimer's disease (AD) and neuroblastoma are distinct conditions that affect the nervous system. However, they share some molecular similarities, particularly concerning the amyloid precursor protei Show more
Alzheimer's disease (AD) and neuroblastoma are distinct conditions that affect the nervous system. However, they share some molecular similarities, particularly concerning the amyloid precursor protein (APP) and related pathways. While previous studies have demonstrated a correlation between neurodegenerative diseases and various tumors, the causality and direction of their relationship remain unclear. Oleacein, one of the most abundant polyphenols in Extra Vergin Olive Oil (EVOO) may exert neuroprotective and/or antitumor effects. In this study, we explored the effects of the polyphenol oleacein, obtained by a simple and efficient sustainable semi-synthesis starting from natural oleuropein, on AD-related genes in SHSY5Y, a human neuroblastoma cell line, and in 3Tg-iAstro cells, immortalized astrocytes from the hippocampus of 3xTg-AD mice, to identify potential shared biological pathways. Show less
Alzheimer's disease (AD) is the most common neurodegenerative pathology among progressive dementias, and it is characterized by the accumulation in the brain of extracellular aggregates of beta-amyloi Show more
Alzheimer's disease (AD) is the most common neurodegenerative pathology among progressive dementias, and it is characterized by the accumulation in the brain of extracellular aggregates of beta-amyloid proteins and neurofibrillary intracellular tangles consisting of τ-hyperphosphorylated proteins. Under normal conditions, beta-amyloid peptides exert important trophic and antioxidant roles, while their massive presence leads to a cascade of events culminating in the onset of AD. The fibrils of beta-amyloid proteins are formed by the process of fibrillogenesis that, starting from individual monomers of beta-amyloid, can generate polymers of this protein, constituting the hypothesis of the "amyloid cascade". To date, due to the lack of pharmacological treatment for AD without toxic side effects, chemical research is directed towards the realization of hybrid compounds that can act as an adjuvant in the treatment of this neurodegenerative pathology. The hybrid compounds used in this work include moieties of a hydroxytyrosol, a nitrohydroxytyrosol, a tyrosol, and a homovanillyl alcohol bound to the N-benzylpiperidine moiety of donepezil, the main drug used in AD. Previous experiments have shown different properties of these hybrids, including low toxicity and antioxidant and chelating activities. The purpose of this work was to test the effects of hybrid compounds mixed with A Show less
The interplay between E2 and E3 enzymes regulates the polyubiquitination of substrates in eukaryotes. Among the several RING-domain E3 ligases in humans, many utilize two distinct E2s for polyubiquiti Show more
The interplay between E2 and E3 enzymes regulates the polyubiquitination of substrates in eukaryotes. Among the several RING-domain E3 ligases in humans, many utilize two distinct E2s for polyubiquitination. For example, the cell cycle regulatory E3, human anaphase-promoting complex/cyclosome (APC/C), relies on UBE2C to prime substrates with ubiquitin (Ub) and on UBE2S to extend polyubiquitin chains. However, the potential coordination between these steps in ubiquitin chain formation remains undefined. While numerous studies have unveiled how RING E3s stimulate individual E2s for Ub transfer, here we change perspective to describe a case where the chain-elongating E2 UBE2S feeds back and directly stimulates the E3 APC/C to promote substrate priming and subsequent multiubiquitination by UBE2C. Our work reveals an unexpected model for the mechanisms of RING E3-dependent ubiquitination and for the diverse and complex interrelationship between components of the ubiquitination cascade. Show less