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Alkaloids are among the natural phytochemicals contained in functional foods and nutraceuticals and have been suggested for the prevention and/or management of oxidative stress and inflammation-mediated diseases. In this review, we aimed to describe the effects of alkaloids in angiogenesis, the process playing a crucial role in tumor growth and invasion, whereby new vessels form. Antiangiogenic compounds including herbal ingredients, nonherbal alkaloids, and microRNAs can be used for the control and treatment of cancers. Several lines of evidence indicate that alkaloid-rich plants have several interesting features that effectively inhibit angiogenesis. In this review, we present valuable data on commonly used alkaloid substances as potential angiogenic inhibitors. Different herbal and nonherbal ingredients, introduced as antiangiogenesis agents, and their role in angiogenesis-dependent diseases are reviewed. Studies indicate that angiogenesis suppression is exerted through several mechanisms; however, further investigations are required to elucidate their precise molecular and cellular mechanisms, as well as potential side effects.

Background:Obesity is a risk factor for some types of cancers. Angiogenesis is a necessary step in the multistage progression of tumors such as melanoma. Previous studies reported that neuropeptide Y (NPY) regulates angiogenesis by activating the Y2 receptor on endothelial cells. The present study examined the effects of the NPY Y2 receptor antagonist on tumor weight, angiogenesis and serum levels of vascular endothelial growth factor (VEGF), VEGF receptor-1 (VEGF-R1), and nitric oxide (NO).Methods:Twenty four male C57BL/6 mice were divided into control and obese groups. The control group was fed a normal diet whereas the obese group was fed a high fat diet. After 16 weeks, 2 × 106 B16F10 melanoma cells were injected subcutaneously into all animals. Half of the control and the obese animals received 1 µM, 100 µL/kg NPY Y2 receptor antagonist (BIIE 0246) intraperitoneally. After two weeks, the animals were sacrificed, and angiogenic factors and tumor weights and angiogenesis were analyzed.Results:Tumor weight in the obese mice was higher than in the control (p<0.05). Treatment with BIIE 0246 reduced tumor weight in the obese animals (p<0.05), without effect on control group (p>0.05). Administration of an NPY Y2 receptor antagonist decreased tumor angiogenesis (evaluated as capillary density/mm2) and serum VEGF concentration in the obese group without altering serum VEGF-R1 and NO concentrations.Conclusions:Blockade of the NPY Y2 receptor suppressed tumor growth in obese mice by affecting tumor angiogenesis. Thus, it seems that NPY and its Y2 receptor antagonist might be new targets in melanoma tumor therapy.

Background: Targeted therapy is a novel, promising approach to anticancer treatment that endeavors to overcome drug resistance to traditional chemotherapies. Patients with the L858R mutation in epidermal growth factor receptor (EGFR) respond to the first generation tyrosine kinase inhibitors (TKIs); however, after one year of treatment, they may become resistant. The T790M mutation is the most probable cause for drug resistance. Third generation drugs, including Osimertinib (AZD9291), are more effective against T790M and other sensitive mutations. Osimertinib is effective against the L844V mutation, has conditional effectiveness for the L718Q mutation, and is ineffective for the Cys797Ser (C797S) mutation. Cells that have both the T790M and C797 mutations are more resistant to third generation drugs. Although research has shown that Osimertinib is an effective treatment for EGFR L844V cells, this has not been shown for cells that have the C797S mutation. This molecular mechanism has not been well-studied.Methods: In the present study, we used the GROMACS software for molecular dynamics simulation to identify interactions between Osimertinib and the kinase part of EGFR in L844V and C797S mutants. Results:We evaluated native EGFR protein and the L844V and C797S mutations' docking and binding energy, kI, intermolecular, internal, and torsional energy parameters. Osimertinib was effective for the EGFR L844V mutation, but not for EGFR C797S. All simulations were validated by rootmean-square deviation (RMSD), root-mean square fluctuation (RMSF), and radius of gyration (ROG).

Similar to captopril, walnut extract normalized dexamethasone-induced hypertension. A part of this beneficial effect apparently involves maintaining balance of the redox system and NO production.