Evaluation of the localization and biological effects of PAMAM G3 dendrimer-biotin/pyridoxal conjugate as HaCaT keratinocyte targeted nanocarrier

Abstract

Recognition of the molecular mechanisms of keratinocyte participation in normal skin homeostasis and in pathogenesis may lead to creation of more effective tools for topical application of cosmetics, cosmeceutics and drugs to a particular location within the skin for prevention and therapy of many skin disorders and diseases. For this purpose, the PAMAM G3 dendrimer with amide linkages of 9 biotin molecules and 10 molecules of pyridoxal phosphate (BC-PAMAM) was constructed, and its biological properties and cellular uptake and localization were investigated in the HaCaT keratinocytes. BC-PAMAM is nontoxic for HaCaT cells, as estimated by two assays (Neutral Red and tetrazolium salt reduction, XTT), and revealed low apoptosis induction at up to 50 µM concentration. Fluorescent labeled BC-PAMAM accumulates in HaCaT cells with high efficiency in a concentration–dependent manner. Its mitochondrial localization, estimated as Mander’s colocalization coefficient, is substantially lower than the native PAMAM, and that correlates with its cytotoxicity. The only undesirable, but significant inhibitory effect on cell mobility, evaluated by the wound healing test, was observed at 10 µM BC-PAMAM. The important anti-inflammatory action of BC-PAMAM was clearly documented by decreased production of total IL-1α, assayed with an ELISA test with unstimulated and stimulated by bacterial antigens (LPS and GroEL) HaCaT cells. Thus, it is expected that the biotin pyridoxal phosphate conjugated PAMAM may be considered as a potential carrier for safe delivery of vitamins and drugs into the epidermis.

New Insights into the Binding Site and Affinity of the Interaction between Biotin and PAMAMs-NH2 via NMR Studies

“…Biotin (Figure B), an essential micronutrient, consists of bicyclic heterocyclic skeleton with an n -valeric acid side chain attached, making it poorly water-soluble and limiting its application. Biotin-PAMAMs-NH 2 attracts much attention owing to increased water solubility of biotin as well as improved uptake of anticancer drugs in cancer cells. − Deeper insight into the interaction with binding sites between PAMAMs-NH 2 and biotin is still needed. PAMAM-NH 2 , being a dendrimer, has many branched repeating units. , These repeating units overlap so much in the 1 H NMR spectra that it is impossible to identify precise interaction sites of biotin-PAMAM-NH 2 .…”

Stepwise Glucoheptoamidation of Poly(Amidoamine) Dendrimer G3 to Tune Physicochemical Properties of the Potential Drug Carrier: In Vitro Tests for Cytisine Conjugates

“…There is a variety of PAMAM terminal amine group modifications reported till now, like PEG-ylation, acylation, and hydroxyalkylation [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 ], which modify not only the basicity of intrinsic nitrogen atoms but also tune surface hydrophilicity vs. hydrophobicity. On the other hand, amine groups are convenient peripheral sites to attach potential ligands like folate or biotin and are responsible for binding a conjugated carrier selectively to cancer cell membranes [ 5 , 8 , 10 , 13 , 14 , 15 , 16 , 17 , 18 ]. Conjugates bearing anticancer drugs, targeting molecules, and surface-modifying substituents may serve as selective and systematically nontoxic anticancer drugs.…”

Biotin-Containing Third Generation Glucoheptoamidated Polyamidoamine Dendrimer for 5-Aminolevulinic Acid Delivery System

“…From previous studies, we know that the G3 Bgh carriers enter the cells of normal fibroblasts (BJ), squamous cell carcinoma (SCC-15), and glioblastoma (U-118 MG) within 24 h in a time-and concentration-dependent manner and are 3-4 times less cytotoxic than the non-biotinylated carrier. All cell lines survived a 50-μM concentration of G3 Bgh as well as keratinocytes (HaCat) [29,42].…”