RESUMO
One-third of systemic lupus erythematosus (SLE) patients experience various degrees of ocular manifestations, with immunosuppressants recommended as a treatment option. Targeted immune suppression via oral administration is challenging due to the harsh gastrointestinal tract environment combined with complex physiological barriers. Here, we report the efficacy of orally administered cyclosporine (CsA)-laden polymer nanoparticles decorated with the ligand - Gambogic Acid (P2Ns-GA-CsA) in sustained lymph node delivery. This is the first report demonstrating the CD71 specificity of P2Ns-GA-CsA in the CD71 knockout mouse model and the influence of spacer length in achieving target tissue bioavailability in a lupus mouse model. P2Ns-GA-CsA effectively regulates T-cell chemotaxis by PD-L1 at a 50 % lower dose compared to conventional CsA in a mouse model exhibiting lupus-associated corneal inflammation. Collectively, these results suggest the possibility for further development of P2Ns-GA to target a diverse range of lymphatic disorders.
RESUMO
ETHNOPHARMACOLOGY RELEVANCE: Alstonia boonei De Wild. (stem bark), Anacardium occidentale L. (stem bark), Azadirachta indica A.Juss (leaves), Enantia chlorantha Oliv. (stem bark), Khaya senegalensis A.Juss (stem bark) Mangifera indica L. (stem bark), and Nauclea latifolia Sm. (stem bark) are used for treating malaria in southwest Nigeria. Surveys revealed that these plants are also employed for treating symptoms of malaria and cerebral malaria in the region. AIM OF THE STUDY: In this study, the effects of freeze-dried extracts of these plants were investigated on synthetic hemozoin (HZ)-induced neuroinflammation, neuronal damage, and increased permeability of brain microvascular endothelial cells. MATERIALS AND METHODS: Effects of freeze-dried plant extracts were investigated on neuroinflammation by measuring levels of pro-inflammatory mediators in culture supernatants, while in-cell western assays were used to measure protein levels of iNOS and NLRP3. Effects on HZ-induced neurotoxicity and ROS generation was measured using MTT and DCFDA assays, respectively. HZ-induced permeability of hCMEC/D3 endothelial cells was determined using the in vitro vascular permeability assay kit. RESULTS: The extracts produced significant (p < 0.05) reduction in TNFα, IL-6, IL-1ß, MCP-1, RANTES and iNOS/NO production in HZ-stimulated BV-2 microglia. Pre-treatment with 50 µg/mL of A. boonei, A. indica, A. occidentale, E. chlorantha and M. indica also resulted in the inhibition of NF-κB activation. Pre-treatment with A. indica produced, A. occidentale, M. indica and A. boonei reduced HZ-induced increased NLRP3 protein expression. HZ-induced increased caspase-1 activity was also reduced by A. boonei, A. occidentale, A. indica, E. chlorantha, and M. indica. Freeze-dried extracts of A. boonei, A. occidentale, A. indica and M. indica produced neuroprotective effect in HT-22 neuronal cells incubated with HZ by preventing HZ-induced neurotoxicity, ROS generation, DNA fragmentation and caspase 3/7 activity. Inhibition of HZ-induced increase in permeability of human hCMEC/D3 brain endothelial cells was also observed with A. boonei, A. occidentale, A. indica and M. indica, while reducing the release of TNFα and MMP-9. CONCLUSIONS: These results suggest that A. boonei, A. occidentale, A. indica and M. indica are neuroprotective through inhibition of neuroinflammation, neuronal damage and increased permeability of blood brain barrier. The outcome of the study provides pharmacological evidence for the potential benefits of plants as herbal treatments for cerebral malaria symptoms.
