Multiple Beneficial Effects of Aloesone from Aloe vera on LPS-Induced RAW264.7 Cells, Including the Inhibition of Oxidative Stress, Inflammation, M1 Polarization, and Apoptosis.

Aloesone is a major metabolic compound in Aloe vera, which has been widely used as a food source and therapeutic agent in several countries. Our recent study demonstrated that aloesone has anti-epileptic effects on glutamate-induced neuronal injury by suppressing the production of reactive oxygen species (ROS). Unless ROS are naturally neutralized by the endogenous antioxidant system, they lead to the activation of inflammation, polarization, and apoptosis. This study aimed to identify the multiple beneficial effects of aloesone and explore its molecular mechanism in macrophages. Hence, the murine macrophage cell line RAW264.7 was pretreated with aloesone and then exposed to lipopolysaccharides (LPS). The results demonstrated that aloesone, within a dosage range of 0.1-100 µM, dramatically decreased the LPS-induced elevation of ROS production, reduced nitric oxide (NO) release, inhibited the M1 polarization of RAW264.7 cells, and prevented cells from entering the LPS-induced early and late phases of apoptosis in a dose-dependent manner. Simultaneously, aloesone significantly decreased the mRNA expression of inflammation-related genes (iNOS, IL-1ꞵ, TNF-α) and increased the expression of antioxidant enzymes (Gpx-1 and SOD-1). The core genes HSP90AA1, Stat3, Mapk1, mTOR, Fyn, Ptk2b, and Lck were closely related to these beneficial effects of aloesone. Furthermore, immunofluorescence staining and flow cytometry data confirmed that aloesone significantly repressed the activation of mTOR, p-mTOR, and HIF-1α induced by LPS and inhibited the protein expression of TLR4, which is the target of LPS. In conclusion, aloesone demonstrated multiple protective effects against LPS-induced oxidative stress, inflammation, M1 polarization, and apoptosis in macrophages, suggesting its potential as a prodrug.

Up-and-coming anti-epileptic effect of aloesone in Aloe vera: Evidenced by integrating network pharmacological analysis, in vitro, and in vivo models.

Background: Aloe vera is a medically valuable plant with anti-epileptic activity; however, its mechanism of action remains unknown. In this study, network pharmacological, in vitro, and in vivo experiments were carried out to explore the potential anti-epileptic components and targets of Aloe vera. Methods: The main active components of Aloe vera were identified by searching the Traditional Chinese Medicine System Pharmacology database. Targets of Aloe vera were predicted using SwissTargetPrediction, whereas information about the epilepsy disease targets was obtained from Gene Cards. The protein-protein interaction network and core targets were screened according to the topological structure and CytoNCA plugin. The glutamate-induced HT22 cell line and pentylenetetrazol-induced seizure rats were used to confirm the effect of aloesone by detecting reactive oxygen species (ROS) and apoptosis, and predicting the targets. Results: A total of 14 core active components were selected based on the screening criteria of oral bioavailability ≥30% and drug-likeness ≥ 0.10. Four compounds, namely linoleic acid, aloesone, isoeleutherol glucosiden qt, and anthranol, demonstrated the potential ability of crossing the blood-brain barrier. A total of 153 targets associated with epilepsy were predicted for the four compounds. Moreover, after network analysis with CytoNCA, 10 targets, namely, MAPK1, SRC, MARK3, EGFR, ESR1, PTGS2, PTPN11, JAK2, PPKCA, and FYN, were selected as the core genes, and SRC, which has been predicted to be the target of aloesone and anthranol, exhibited the highest subgraph centrality value. In vitro experiments confirmed that aloesone treatment significantly inhibited the glutamate-induced neuronal injury by reducing the intracellular ROS content and the early phase of apoptosis. Additionally, treatment with 50 mg/kg aloesone resulted in anti-seizure effects by reducing the seizure score and prolonging the latent period in acute and chronic rats. Furthermore, aloesone treatment increased the phosphorylation of c-SRC at Y418 and reduced the phosphorylation at Y529, simultaneously activating c-SRC. Conclusion: Integrating network pharmacology with in vitro and in vivo experiments demonstrated that aloesone, which inhibited seizure by activating c-SRC, is a potential anti-seizure compound present in Aloe vera.