The Role of Alpha-lipoic Acid Supplementation in the Prevention of Diabetes Complications: A Comprehensive Review of Clinical Trials.

Alpha-lipoic acid (ALA) is a substantial antioxidant in the prevention of diabetes and diabetes complications. It can regenerate other antioxidants like vitamin E, vitamin C, Coenzyme Q10 and glutathione and is often known as a universal antioxidant. Antioxidants play a role in diabetes treatment due to hyperglycemia-induced stimulation of the polyol pathway and formation of advanced glycation end products (AGE) and reactive oxygen species (ROS). Clinical trials examining alpha-lipoic acid supplementation on diabetic neuropathy, nephropathy, cardiomyopathy and erectile dysfunction display positive results, particularly in pain amelioration in neuropathy, asymmetric dimethylarginine reductions in nephropathy and improved oscillatory potential and contrast sensitivity in retinopathy. In diabetic cardiomyopathy (DCM), ALA offers protection through inhibition of NF-kB activation, reduction of fas-ligand and decrease in matrix metalloproteinase-2. This comprehensive review summarises and provides an understanding of the importance of alpha- lipoic acid supplementation to prevent diabetes complications.

Novel folic acid conjugated Fe3O4-ZnO hybrid nanoparticles for targeted photodynamic therapy.

A novel folic acid conjugated core-shell hybrid iron oxide-zinc oxide nanoparticle was developed for applications as a photosensitier (PS) in photodynamic therapy. Photodegradation studies on methylene blue demonstrated significantly enhanced photophysical properties of the produced nano-PSs, due to the charge recombination via electron trapping by dissolved Fe3+. A time and dose dependant toxicity associated with the nano-PSs was observed upon exposure to human epithelial colorectal adenocarcinoma (Caco-2) cells in the dark. UV irradiation of the synthesised nano-PSs resulted in a significant photo-killing effect with drastic reduction in Caco-2 cell viability to as low as 6%. Reduction in viability upon exposure was due fundamentally to cellular interactions with light irradiated PSs as the influence of radiation alone was subtracted. FA conjugation further enhanced the photo-killing effect.

Enhanced gene expression in tumors after intravenous administration of arginine-, lysine- and leucine-bearing polyethylenimine polyplex.

The potential of gene therapy to treat cancer is currently limited by the low expression of therapeutic genes in the tumors. Because amino acids are known to have excellent properties in cell penetration and gene expression regulation, we investigated if the conjugation of arginine (Arg), lysine (Lys) and leucine (Leu) onto the surface of the gene delivery system polyethylenimine (PEI) could lead to an improved gene expression in tumors. The intravenous administration of Arg-, Lys- and Leu-bearing PEI polyplexes led to a significant increase of gene expression in the tumor, with a ß-galactosidase expression amount at least threefold higher than that obtained after treatment with unmodified PEI polyplex. The three amino acid-bearing PEI polyplexes led to similar levels of gene expression in the tumor. The treatments were well tolerated by the mice. Arg-, Lys- and Leu-bearing PEI polyplexes are therefore highly promising gene delivery systems for cancer therapy.