Alzheimer’s disease (AD) is a progressive neurodegenerative disorder which usually occurs in the elderly. The accumulation of β-amyloid and the formation of neurofibrillary tangles are considered as the main pathogenies of AD. Research suggests that β-secretase 1 (BACE1) plays an important role in the formation of β-amyloid. Discovery of new BACE1 inhibitors has become a significant method to slow down the progression of AD or even cure this kind of disease. This review summarizes the different types and the structural modification of these new BACE1 inhibitors.

In this paper, a new and efficient synthesis of 6-O-methylscutellarein (3), the major metabolite of the natural medicine scutellarin, is reported. Two hydroxyl groups at C-4′ and C-7 in 2 were selectively protected by chloromethyl methyl ether after the reaction conditions were optimized, then 6-O-methyl-scutellarein (3) was produced in high yield after methylation of the hydroxyl group at C-6 and subsequent deprotection of the two methyl ether groups.

Context Scutellarin (1) has been widely used in China to treat acute cerebral infarction and paralysis induced by cerebrovascular diseases. However, scutellarin (1) has unstable metabolic characteristics. Objective The metabolic profile of 6-O-scutellarein was studied to determine its metabolic stability in vivo. Materials and methods In this study, a method of UFLC/Q-TOF MS was used to study the 6-O-methyl-scutellarein metabolites in rat plasma, urine, bile and faeces after oral administration of 6-O-methyl-scutellarein (3). One hour after oral administration of 6-O-methyl-scutellarein (3) (34 mg/kg), approximately 1 mL blood samples were collected in EP tubes from all groups. Bile, urine and faeces samples were collected from eight SD rats during 0–24 h after oral administration. The mass defect filtering, dynamic background subtraction and information dependent acquisition techniques were also used to identify the 6-O-methyl-scutellarein metabolites. Results The parent compound 6-O-methyl-scutellarein (3) was found in rat urine, plasma, bile and faeces. The glucuronide conjugate of 6-O-methyl-scutellarein (M1, M2), diglucuronide conjugate of 6-O-methyl-scutellarein (M3), sulphate conjugate of 6-O-methyl-scutellarein (M4), glucuronide and sulphate conjugate of 6-O-methyl-scutellarein (M5), methylated conjugate of 6-O-methyl-scutellarein (M6) were detected in rat urine. M1, M2 and M3 were detected in rat bile. M1 was found in rat plasma and M7 was detected in faeces. Discussion and conclusion Because the parent compound 6-O-methyl-scutellarein (3) was found in rat urine, plasma, bile and faeces, we speculate that 6-O-methyl-scutellarein (3) had good metabolic stability in vivo. This warrants further study to develop it as a promising candidate for the treatment of ischemic cerebrovascular disease.

Cervical cancer ranks as the fourth most prevalent cancer and cause of cancer-related mortality among women globally. It exhibits a recurrence/metastasis rate of approximately 30% and a dismal 5-year survival of only 17% in metastatic cases. Despite significant advancements in surgical techniques, chemoradiotherapy, and targeted therapies, effective treatment options for metastatic cervical cancer remain limited. This study explored Polyphyllin I (PPI), which is a monomeric compound derived from the Rhizoma of Paris Polyphyllin, as a potential inhibitor of cervical cancer metastasis. Mechanistically, PPI directly interacted with β-catenin at the Ser552 site, inhibiting its phosphorylation and subsequent nuclear translocation, thereby suppressing TCF/LEF transcriptional activity and downstream EMT transcription factors (ZEB1, Slug, Snail, and Twist). Notably, PPI promoted β-catenin degradation via the autophagy–lysosomal pathway, as confirmed by CHX chase assays and the detection of the p62 and LC3 proteins, without altering the mRNA levels of β-catenin. In vitro experiments demonstrated that PPI effectively suppressed the migration and invasion of HO-8910PM cells by reversing the process of EMT. Additionally, PPI effectively inhibited TCF/LEF signaling, leading to a reduction in the transcription levels of EMT-associated transcription factors (EMT-TFs), which was mediated by the TCF/LEF family downstream of β-catenin. Furthermore, PPI exhibited inhibitory effects on proliferation, migration, and invasion in both HPV-positive (SiHa) and HPV-negative (C33A) cervical cancer cells. In vivo, PPI significantly suppressed peritoneal metastasis in a luciferase-labeled HO-8910PM xenograft mouse model. These findings reveal the dual role of PPI in blocking β-catenin signaling and inducing β-catenin depletion, thereby effectively restraining metastatic progression. This study underscores the potential of PPI as a promising therapeutic candidate for targeting cervical cancer metastasis through autophagy-mediated β-catenin regulation, offering a novel strategy to address current treatment limitations.

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a master regulator of the cellular antioxidant response and a promising therapeutic target for Parkinson’s disease (PD). Resibufogenin (RBG), a bioactive bufadienolide from toad venom, has been identified as a potential Nrf2 agonist; however, its application is limited by cytotoxicity and poor drug-like properties. Herein, we report the rational design, synthesis, and biological evaluation of a series of RBG derivatives modified at the C3, C14–C15, and C17 positions. Systematic structure–activity relationship (SAR) studies identified 2-5c, featuring a C3 2-chloroacryloyl group and a C17 pyrimidine substitution, as a potential Nrf2 activator (EC₅₀ = 4.18 μM), exhibiting approximately 7-fold greater activity than RBG. Importantly, 2-5c demonstrated neuroprotective effects in MPP⁺-induced BV2 microglial cells and effectively ameliorated motor deficits in an MPTP-induced PD mouse model. These findings suggest that 2-5c represents a promising candidate for further investigation in the development of novel Nrf2-based therapies for PD.