Preclinical studies on melanogenesis proteins using a resveratrol-nanoformula as a skin whitener.

A naturally occurring polyphenol called trans-resveratrol has received a lot of attention due to its possible health advantages for humans. The low solubility of trans-resveratrol and its isomerization upon UV exposure strongly limit its application as a skin-whitening agent. In the present study, to increase trans-resveratrol solubility, a new nanoformula was created by combining hydrophilic surfactants and oils. Trans-Resveratrol nanoformula has been prepared, characterized, and applied as a skin-whitening agent on the dorsal skin of Guinea pigs. The optimized trans-resveratrol nanoformula with a particle size of 63.49 nm displayed a single peak and a polydispersity index [0.36 ± 0.02]. In addition, the zeta potential of the optimized formula was -30.4 mV, confirming the high stability of this nanoformula. The melanin contents in the trans-resveratrol nanoformula-treated group were substantially lower than those of the control and the blank nanoformula-treated groups after staining of the dorsal skins [black areas] of guinea pigs with Fontana Mountain dye. The pigmentation index in the control, blank nanoformula, and optimized trans-resveratrol nanoformula were 329.4 ± 36.9, 335.8 ± 71.4, and 124.8 ± 19.6 respectively. Confirming this finding, immunohistochemistry analysis of skin tissues revealed that the expressions of melanogenesis-regulating proteins such as tyrosinase and microphthalmia-associated transcription factor were down-regulated. The safety of topical application of trans-resveratrol nanoformula was validated by no changes in free radical levels and oxidative stress markers proteins in the livers and kidneys of guinea pigs at the end of the experiment. Conclusions: A novel trans-resveratrol nanoformula as well as the mechanism whereby it promotes skin whitening effects were presented. Furthermore, the study illustrated that trans-resveratrol nanoformula is safe, non-toxic, and can be applied for skin whitening, although more research on human skin is needed.

Development of novel cyanopyridines as PIM-1 kinase inhibitors with potent anti-prostate cancer activity: Synthesis, biological evaluation, nanoparticles formulation and molecular dynamics simulation.

Recently, inhibition of PIM-1 enzyme is found as an effective route in the fight against proliferation of cancer. Herein, new cyano pyridines that target PIM-1 kinase were designed, synthesized, and biologically evaluated. Two prostate cell lines were used to examine each of the new compounds in vitro for anticancer activity, namely, PC-3 and DU-145. The cyanopyridine derivatives 2b, 3b, 4b, and 5b with an N,N-dimethyl phenyl group at the pyridine ring's 4-position showed considerable antitumor effect on the tested cell lines. Additionally, the high selectivity index revealed that these compounds were less cytotoxic to normal WI-38 cells. Furthermore, they exhibited strong inhibitory effect on PIM-1 having IC50 = 0.248, 0.13, 0.326 and 0.245 µM, respectively. The most powerful derivatives2b, 3b, 4b, and 5b, were chosen for further examination of their inhibitory potential on both kinases (PIM-2 and PIM-3). Interestingly, upon loading compound 3b in a cubosomes formulation with nanometric size, improvements in cytotoxicity and inhibitory effect on PIM-1 kinase were observed. In silico ADME parameters study revealed that compound 3b is orally bioavailable without penetration to the blood-brain barrier. Further, the docking simulations revealed the ability of our potent compounds to well accommodate the PIM-1 kinase active site forming stable complexes. In a 150 ns MD simulation, the most powerful PIM-1 inhibitor 3b produced stable complex with the PIM-1 enzyme (RMSD = 1.76). Furthermore, the 3b-PIM-1 complex has the low binding free energy (-242.2 kJ/mol) according to the MM-PBSA calculations.

Superiority of aromatase inhibitor and cyclooxygenase-2 inhibitor combined delivery: Hyaluronate-targeted versus PEGylated protamine nanocapsules for breast cancer therapy.

Despite several reports have revealed the beneficial effect of co-administration of COX-2 inhibitors with aromatase inhibitors in managing postmenopausal breast cancer; no nanocarriers for such combined delivery have been developed till now. Therefore, protamine nanocapsules (PMN-NCs) have been developed to co-deliver letrozole (LTZ) that inhibits aromatase-mediated estrogen biosynthesis and celecoxib (CXB) that synergistically inhibits aromatase expression. Inspired by the CD44-mediated tumor targeting ability of hyaluronate (HA), we developed HA-coated PMN-NCs (HA-NCs) via electrostatic layer-by-layer assembly. Moreover, multi-compartmental PEGylated phospholipid-CXB complex bilayer enveloping PMN-NCs (PEG-NCs) were designed for conferring biphasic CXB release from the phospholipid corona and oily core as well as enabling passive-targeting. The NCs demonstrated excellent stability, prolonged circulation and could be scaled up with the aid of spray-drying technology. Hemolysis, serum stability and cytotoxicity studies confirmed the superiority of combined LTZ-CXB nano-delivery. Mechanistically, the NCs especially HA-NCs and PEG-NCs demonstrated precious anti-tumor effects in vivo revealed as reduction in the tumor volume and aromatase level, increased apoptosis, as well as inhibition of VEGF, NF-κB and TNF-α augmented by histopathological and immunohistochemical studies. Overall, our approach provided for the first time a potential strategy for targeted LTZ-CXB combined therapy of hormone-dependent breast cancer via singular nanocapsule delivery system.

Multi-Reservoir Phospholipid Shell Encapsulating Protamine Nanocapsules for Co-Delivery of Letrozole and Celecoxib in Breast Cancer Therapy.

PURPOSE: In the current work, we propose a combined delivery nanoplatform for letrozole (LTZ) and celecoxib (CXB). METHODS: Multi-reservoir nanocarriers were developed by enveloping protamine nanocapsules (PRM-NCs) within drug-phospholipid complex bilayer. RESULTS: Encapsulation of NCs within phospholipid bilayer was confirmed by both size increase from 109.7 to 179.8 nm and reduction of surface charge from +19.0 to +7.78 mV. The multi-compartmental core-shell structure enabled biphasic CXB release with initial fast release induced by complexation with phospholipid shell followed by prolonged release from oily core. Moreover, phospholipid coating provided protection for cationic PRM-NCs against interaction with RBCs and serum proteins enabling their systemic administration. Pharmacokinetic analysis demonstrated prolonged circulation and delayed clearance of both drugs after intravenous administration into rats. The superior anti-tumor efficacy of multi-reservoir NCs was manifested as powerful cytotoxicity against MCF-7 breast cancer cells and marked reduction in the mammary tumor volume in Ehrlich ascites bearing mice compared with free LTZ-CXB combination. Moreover, the NCs induced apoptotic caspase activation and marked inhibition of aromatase expression and angiogenic marker, VEGF as well as inhibition of both NFκB and TNFα. CONCLUSIONS: Multi-reservoir phospholipid shell coating PRM-NCs could serve as a promising nanocarrier for parenteral combined delivery of LTZ and CXB.