Alzheimer’s disease (AD) is a debilitating neurological disorder, and currently, there is no cure for it. Several pathologic alterations have been described in the brain of AD patients, but the ultimate causative mechanisms of AD are still elusive. The classic hallmarks of AD, including am-yloid plaques (Aβ) and tau tangles (tau), are the most studied features of AD. Unfortunately, all the efforts targeting these pathologies have failed to show the desired efficacy in AD patients so far. Neuroinflammation and impaired autophagy are two other main known pathologies in AD. It has been reported that these pathologies exist in AD brain long before the emergence of any clinical manifestation of AD. Microglia are the main inflammatory cells in the brain and are considered by many researchers as the next hope for finding a viable therapeutic target in AD. Interestingly, it appears that the autophagy and mitophagy are also changed in these cells in AD. Inside the cells, autophagy and inflammation interact in a bidirectional manner. In the current review, we briefly discussed an overview on autophagy and mitophagy in AD and then provided a comprehensive discussion on the role of these pathways in microglia and their involvement in AD pathogenesis.

Melittin, an amphipathic 26-residue peptide, is the main component of honey bee venom. Studies have been demonstrated that melittin has an inhibitory effect on proliferation of cancer cells. However, the precise mechanism of action is not completely understood. In the present study we have shown that purified melittin from Iranian honey bee venom shows anti-cancer effects on human cervical cancer cell line through induction of apoptosis. The venom was collected from Iranian honey bee (Apis mellifera meda) and melittin isolated using reversed phase HPLC. Biological activity of melittin was analyzed by hemolytic test on human red blood cells. In order to investigate whether melittin inhibits proliferation of cervical cancer cells, the viability of the melittin treated HeLa cell line was measured via MTT assay. Finally, cell death analysis was performed using Propidum iodide and Annexin V-FITC dual staining. The results showed that the half hemolytic concentration (HD50) induced by mellitin was 0.5 µg/ml in free FBS solution. IC50 obtained after 12 h at 1.8 µg/ml by MTT assay. According to flow cytometric analysis, melittin induced apoptosis at concentrations more than 1 µg/ml. These results suggest that melittin induces apoptotic cell death in cervical cancerous cells as observed by flow cytometric assay. It is concluded that melittin could be regarded as a potential candidate in future studies to discovery of new anticancer agents.

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The present study indicated that melittin has an anticancer effect on gastric cancer AGS cells and stimulates necrotic cell death in these cells.