An alcoholic extract of Thuja orientalis L. leaves inhibits autophagy by specifically targeting pro-autophagy PIK3C3/VPS34 complex

PACAP-Sirtuin3 alleviates cognitive impairment through autophagy in Alzheimer's disease

BACKGROUND

Autophagy is vital in the pathogenesis of neurodegeneration. Thus far, no studies have specifically investigated the relationship between pituitary adenylate cyclase-activating polypeptide (PACAP) and autophagy, particularly in the context of Alzheimer's disease (AD). This study used in vitro and in vivo models, along with clinical samples, to explore interactions between PACAP and autophagy in AD.

METHODS

AD model mice were administered 6 μl of 0.1 mg/ml PACAP liquid intranasally for 4 weeks, then subjected to behavioral analyses to assess the benefits of PACAP treatment. The underlying mechanisms of PACAP-induced effects were investigated by methods including real-time quantitative polymerase chain reaction, RNA sequencing, immunofluorescence, and western blotting. Exosomes were extracted from human serum and subjected to enzyme-linked immunosorbent assays to examine autophagy pathways. The clinical and therapeutic implications of PACAP and autophagy were extensively investigated throughout the experiment.

RESULTS

Impaired autophagy was a critical step in amyloid β (Aβ) and Tau deposition; PACAP enhanced autophagy and attenuated cognitive impairment. RNA sequencing revealed three pathways that may be involved in AD progression: PI3K-AKT, mTOR, and AMPK. In vivo and in vitro studies showed that sirtuin3 knockdown diminished the ability of PACAP to restore normal autophagy function, resulting in phagocytosis dysregulation and the accumulation of pTau, Tau, and Aβ. Additionally, the autophagic biomarker MAP1LC3 demonstrated a positive association with PACAP in human serum.

CONCLUSIONS

PACAP reverses AD-induced cognitive impairment through autophagy, using sirtuin3 as a key mediator. MAP1LC3 has a positive relationship with PACAP in humans. These findings provide insights regarding potential uses of intranasal PACAP and sirtuin3 agonists in AD treatment.

TRIAL REGISTRATION

NCT04320368.

Inhibition of autophagy potentiates the cytotoxicity of the irreversible FGFR1-4 inhibitor FIIN-2 on lung adenocarcinoma

For patients with platinum-resistant lung adenocarcinoma (LUAD), the exploration of new effective drug candidates is urgently needed. Fibroblast growth factor receptors (FGFRs) have been identified as promising targets for LUAD therapy. The purpose of this study was to determine the exact role of the irreversible FGFR1-4 inhibitor FIIN-2 in LUAD and to clarify its underlying molecular mechanisms. Our results demonstrated that FIIN-2 significantly inhibited the proliferation, colony formation, and migration of A549 and A549/DDP cells but induced the mitochondria-mediated apoptosis of these cells. Meanwhile, FIIN-2 increased the autophagy flux of A549 and A549/DDP cells by inhibiting the mammalian target of rapamycin (mTOR) and further activating the class III PI3K complex pathway. More importantly, in vivo and in vitro experiments showed that autophagy inhibitors could enhance the cytotoxicity of FIIN-2 on A549 and A549/DDP cells, confirming that FIIN-2 induced protective autophagy. These findings indicated that FIIN-2 is a potential drug candidate for LUAD treatment, and its use in combination with autophagy inhibitors might be an efficient treatment strategy, especially for patients with cisplatin resistance.