BackgroundPoly lactic-co-glycolic acid (PLGA) based nanoparticles are considered to be a promising drug carrier in tumor targeting but suffer from the high level of opsonization by reticuloendothelial system due to their hydrophobic structure. As a result surface modification of these nanoparticles has been widely studied as an essential step in their development. Among various surface modifications, human serum albumin (HSA) possesses advantages including small size, hydrophilic surface and accumulation in leaky vasculature of tumors through passive targeting and a probable active transport into tumor tissues.MethodsPLGA nanoparticles of docetaxel were prepared by emulsification evaporation method and were surface conjugated with human serum albumin. Fourier transform infrared spectrum was used to confirm the conjugation reaction where nuclear magnetic resonance was utilized for conjugation ratio determination. In addition, transmission electron microscopy showed two different contrast media in conjugated nanoparticles. Furthermore, cytotoxicity of free docetaxel, unconjugated and conjugated PLGA nanoparticles was studied in HepG2 cells.ResultsSize, zeta potential and drug loading of PLGA nanoparticles were about 199 nm, −11.07 mV, and 4%, respectively where size, zeta potential and drug loading of conjugated nanoparticles were found to be 204 nm, −5.6 mV and 3.6% respectively. Conjugated nanoparticles represented a three-phasic release pattern with a 20% burst effect for docetaxel on the first day. Cytotoxicity experiment showed that the IC50 of HSA conjugated PLGA nanoparticles (5.4 μg) was significantly lower than both free docetaxel (20.2 μg) and unconjugated PLGA nanoparticles (6.2 μg).ConclusionIn conclusion surface modification of PLGA nanoparticles through HSA conjugation results in more cytotoxicity against tumor cell lines compared with free docetaxel and unconjugated PLGA nanoparticles. Albumin conjugated PLGA nanoparticles may represent a promising drug delivery system in cancer therapy.

Mitochondria have essential role in cellular energy metabolism and defects in their function lead to many metabolic diseases. Mitochondrial DNA (mtDNA) mutations have been associated with number diseases such as nonsyndromic and aminoglycoside-induced hearing loss. Mutational screening of entire 12SrRNA and tRNA (ser (UCN)) genes in 107 unrelated Iranian patients with amino glycoside-induced and nonsyndromic bilateral hearing loss by direct sequencing analysis method were performed. Twenty different homoplasmic sequence variants were identified; including fifteen common polymorphisms, two putatively pathogenic variants: m.921T>C and m.1005T>C, one 12SrRNA sequence variant m.739C>T and two nucleotides substitution; m.1245T>C and m.1545T>C. Deafness-associated mutation, m.1555A>G, was not found. In our patients we found the mutation 1005 was associated with R haplogroup. These finding show that m.1555A>G mutation is not important in our population. Nucleotide change, m.739C>T, previously reported with very low frequency. We suggested the variation of two nucleotides 1245 and 1545 that localized at conserved site of 12SrRNA may be new candidate for amino glycoside-induced and nonsyndromic hearing impairment associated mutations. However, aminoglycoside exposure is a risk factor for clinical phenotype appearance of these mutations.

This study discussed the proximate composition, nutritional properties, amino acid profile and antiamylase activity of royal jelly, propolis and bee bread. Royal jelly, bee bread and propolis have lower protein and lipid and more sugar than soybeans and eggs. Soybeans have the highest energy, followed by bee bread, propolis, royal jelly and eggs. Eggs have the highest protein digestibility, followed by royal jelly, bee bread, soybeans and propolis. The primary amino acids in bee bread, royal jelly and propolis are proline, glycine, lysine, alanine, aspartic acid, serine, glutamic acid, threonine, arginine, leucine, tyrosine, phenylalanine, histidine, b-aminobutyric acid, valine, asparagine and methionine. Amino acids from royal jelly, propolis and bee bread inhibited amylase by increasing Km/Vmax and decreasing Vmax and Km through un-competitive or non-competitive strategies. Molecular docking, ultraviolet absorption and fluorescence quenching analysis showed that amino acids interact with amylase structure at the allosteric site through van der Waals interactions and hydrogen bonds. Bee products can be used as food supplements, ingredients and medications to manage diabetes by inhibiting amylase.

This work explores the proximate composition, fatty acid profile, nutritional quality, and anti-amylase activity of propolis, royal jelly, and bee bread. The differential FTIR patterns of propolis, royal jelly, and bee bread reflect these products have different proximate compositions and nutritional properties. The values for carbohydrate, fat, and protein values of be products are similar to egg and soya. The primary fatty acids bee bread and bee propolis are palmitic, linolenic, oleic, linoleic, myristic, and docosanoic acids. The primary fatty acids in royal jelly are 2-dodecenedioic, 10-hydroxy-2-decenoic, decanedioic, linoleic, 10-hydroxydecanoic acid 3-hydroxy-decanoic acids, respectively. The propolis, bee bread, and royal jelly have well-balanced saturated, unsaturated, monounsaturated, polyunsaturated, omega-3, and omega-6 fatty acids. Their nutritional quality, including omega-6/omega-3, thrombogenicity, atherogenicity, hypocholesterolemic, nutritional value, and peroxidizability indexes, are similar to egg and soya. Fatty acids inhibit amylase by increasing Km/Vmax and decreasing Vmax and Km through an un-competition or non-competition strategy. Molecular docking, ultraviolet absorption, and fluorescence quenching analysis reveal that fatty acids interact with amino acid residues of amylase through Van der Waals and hydrogen bonds interactions. Functional fatty acids from bee products can be used in a number of food supplements, food ingredients, and medications to provide carbohydrate-degrading enzymes.

No abstract