The blood-brain barrier (BBB) poses a challenge for the treatment of cerebrovascular diseases including cerebral ischemia-reperfusion injury, Parkinson's syndrome, and cerebral tumors. Nanotechnology has developed as a promising strategy for drug delivery applications to the brain, especially liposomes (Lps) that have shown an intrinsic ability to cross the BBB. Angiopep-2 (ANG), a ligand for low-density lipoprotein receptor-related protein-1 (LRP1), is a good prospect for use as a targeting ligand for brain delivery using Lps. It was also reported that Polysorbate 80 (Tween 80, T80) plays a special role in brain targeting. Moreover, the nasal drug delivery method has attracted increased attention with its brain targeting capability in the clinical treatment of cerebrovascular diseases. The aim of this work was to evaluate the capability of Angiopep-conjugated Polysorbate 80-Coated Liposomes in the delivery of cyclovirobuxine D across the BBB in vitro and in vivo. For this purpose, we first synthesized DSPE-PEG2000-Angiopep-2 then cyclovirobuxine D was encapsulated in Angiopep-conjugated Polysorbate 80-Coated Liposomes (T80-An2-CVB-D-Lps) prepared by thin film evaporation and an ultrasonic technique. Formulations were characterized in terms of encapsulation efficiency, transmission electron microscope (TEM) morphology, size distribution, and zeta potential. Angiopep-conjugated Polysorbate 80-Coated Liposomes enhanced in vitro BBB transport of CVB-D compared to the nontargeted liposomes and the CVB-D solution in the BBB model consisting of brain microvascular endothelial (bEnd.3) cells. To evaluate the brain targeting of T80-An2-CVB-D-Lps in vivo, microdialysis samples were collected from the striatum and blood simultaneously. Rats were dosed with brain-targeting liposomes, CVB-D liposomes and CVB-D solution by intranasal administration and with brain-targeting liposomes by intravenous injection. The results showed that T80-An2-CVB-D-Lps were spherical, small (approximately 80 nm), homogeneously dispersed, negatively charged and possessed a high encapsulation efficiency. T80-An2-CVB-D-Lps crossed the BBB model better than the other treatments did. In addition, in a pharmacodynamic study, there was a higher AUC in the brain after T80-An2-CVB-D-Lps by intranasal administration. In conclusion, T80-An2-Lps can enhance the BBB permeability and improve the transport of CVB-D to the brain. This coadministration strategy can be utilized to enhance the brain accumulation in other cerebrovascular diseases.

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Patients with ulcerative colitis (UC) have been found to be frequently associated with secondary liver injury (SLI). In this study, we investigated the protective effect of GA on dextran sodium sulfate (DSS)-induced SLI in mice and its mechanism. The SLI was established by adding 4% DSS in the drinking water of mice, and the effects of GA (5, 20 mg/kg, p.o., once a day for 7 days) in hepatic tissues were analyzed. HepG2 cells were induced by lipopolysaccharide (LPS) to detect the effect of GA on ferroptosis and the underlying mechanism. Pathological damage was determined by H&E. Liver parameters (AST and ALT), antioxidant enzyme activities (MDA and SOD), and the level of Fe2+ in the liver were detected by kits. Cytokine levels (TNF-α, IL-1β, and IL-6) and Gpx4 activity in the liver were detected by ELISA. Finally, the activation of nuclear factor erythroid 2-like 2 (Nrf2) was detected to explore the mechanism. The results indicated that GA significantly attenuated DSS-induced hepatic pathological damage, liver parameters, and cytokine levels and increased the antioxidant enzyme activities. Moreover, GA attenuated ferroptosis in DSS-induced liver injury and upregulated Gpx4 expression in DSS-induced mice. Mechanistic experiments revealed that GA activated Nrf2 in mice. Taken together, this study demonstrates that GA can alleviate ferroptosis in SLI in DSS-induced colitis mice, and its protective effects are associated with activating the Nrf2–Gpx4 signaling pathway.

Background. Hepatocellular carcinoma (HCC) is characterized by poor diagnosis and high mortality. Novel and efficient therapeutic agents are urgently needed for the treatment. Hedyotis diffusa Willd (HDW) is used to treat cancers, especially HCC in China. Purpose. The study aimed to identify the main anti-HCC extract in HDW and to explore the mechanism of the active extract. Materials and Methods. The high-performance liquid chromatography-quadrupole-time of flight mass spectrometry (HPLC-QTOF-MS) method was used for the simultaneous determination of main compounds in the ethyl acetate fraction of HDW (EHDW). The toxicity test of different HDW fractions was carried out on larvae at 2 day-post-fertilization (dpf) for 72 h. The in vivo anti-HCC effect of different HDW fractions was evaluated on a zebrafish tumor model by immersion administration. The antiproliferative effect of HDW fractions was determined with MTT assay, as well as hematoxylin and eosin (HE) staining assay. Hoechst 33258 staining was used to observe changes in nucleus morphology. Flow cytometry analysis was used to investigate apoptosis induction. Western blot analysis was used to examine apoptosis-related proteins, and key proteins in JNK/Nur77 signaling pathway. SP600125 was served to validate the apoptotic mechanism. Results. EHDW showed the strongest tumor cell growth inhibitory effect on zebrafish tumor model. Further study revealed that EHDW induced apoptosis in zebrafish tumor model and in cultured Hep3B cells. Meanwhile, it has been shown that the levels of BCL2-associated X (Bax), cytochrome c (cyto c), cleaved-caspase 3, and poly-ADP-ribose polymerase (PARP) cells were upregulated. In contrast, the level of antiapoptotic B cell lymphoma-2 (Bcl-2) was downregulated in Hep3B cells. Additionally, EHDW activated JNK/Nur77 pathway by increasing the levels of p-JNK(Thr183/Tyr185) and p-Nur77(Ser351). Further study showed that blockage of JNK by SP600125 reversed EHDW-induced JNK/Nur77 pathway and the downstream apoptotic proteins. Conclusion. In conclusion, EHDW exerted the anti-HCC effect, which may be attributed to the activation of JNK/Nur77 pathway. This study supported the rationale of HDW as an HCC therapeutic agent.