Reducing Self-Assembly by Increasing Net Charge: Effect on Biological Activity of Mastoparan C.

The ability of amphipathic peptides to arrange themselves in aqueous solutions, known as self-assembly, has been found to reduce the effectiveness of these peptides in interacting with cell membranes. Therefore, minimizing their tendency to self-assemble could be a potential strategy for enhancing the pharmacological properties of antimicrobial peptides (AMPs). To explore this idea, this study prepared a series of natural peptides mastoparan C (MPC) with increased net charge and hydrophilicity via alanine-to-lysine substitution and investigated the impact on the biological activity. The preliminary data suggested the influence of both the overall positive charge and the position of a lysine residue on the self-assembly of MPC and its derivatives. Besides, the analogue MPC-A5K,A8K displayed higher anticancer activity and comparable antimicrobial activity with significantly lower hemolysis than MPC. Hence, reducing self-assembly by expanding the cationic area could be a promising approach for developing potent and selective AMPs.

The use of Huperzia species for the treatment of Alzheimer's disease.

Alzheimer's disease (AD), which relates to nervous degeneration, is the most popular form of memory loss. The pathogenesis of AD is not fully understood, and there are no therapies for this disorder. Some drugs have been used in clinical applications for preventing and treating AD, but they have significant adverse reactions. Therefore, there is a need to develop treatment for AD. Traditional medicine has used many medicinal plants to alleviate the symptoms of AD. Medicinal plants may reduce neurodegenerative disorders with fewer side effects than chemical drugs, and they are promising drug candidates for AD therapy. This review is the summary of the pathogenesis and treatments of AD and includes information about the chemistry and bioactivities of some medicinal plants from the Huperzia species, such as Huperzia saururus, Huperzia selago, Huperzia phlegmaria, Huperzia fargesii, Huperzia serrata, Huperzia reflexa and Huperzia quadrifariata, that are used for the treatment of AD. We searched literature, including Medline, Embase, Google Scholar and PubMed database, and did a bibliographic review of relevant articles. Key words included Huperzia species, huperzine, huperin, Huperzia and Alzheimer's disease. We found that the main bioactive compounds of the Huperzia species are alkaloids, which have shown significant effects on preventing the development of AD. They are new promising compounds against AD due to their antioxidant, anti-inflammatory and acetylcholinesterase inhibitory activities in the neural system. Our conclusion from this review is that the Huperzia species are potential source containing various pharmaceutical compounds for the treatment of AD.

Phytochemicals and antidiabetic activity of the aqueous extract of the Punica granatum fruit in streptozotocin-induced diabetic mice.

The present study investigated the phytochemicals and antidiabetic effect of the aqueous extract of the fruit of Punica granatum Linn. in streptozotocin (STZ)-induced diabetic mice. The fruit of P. granatum was extracted with water. The phytochemicals of the water extract were investigated by the liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. The water extract of P. granatum at doses of 150 and 300 mg/kg body weight (bw) was administered to mice for 21 days, and blood glucose level, triglyceride, total cholesterol, low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein-cholesterol, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) enzyme were estimated. Analyzed phytochemicals showed the fruit of P. granatum Linn has a high amount of phenolic and flavonoid compounds, which provide beneficial effect for this plant. The oral administration of the fruit extract of P. granatum at doses of 150 and 300 mg/kg bw for 21 days significantly reduced blood glucose level, triglycerides, serum cholesterol, LDL-cholesterol, AST and ALT enzyme. Our results suggested that the fruit extract of P. granatum has strong antidiabetic effect in STZ-induced diabetic mice. The fruit of this plant might be a potential source of drug for treatment of diabetes.