Preparation, Characterization, and In Vivo Pharmacokinetic Evaluation of Polyvinyl Alcohol and Polyvinyl Pyrrolidone Blended Hydrogels for Transdermal Delivery of Donepezil HCl

Transdermal delivery systems are emerging platforms for the delivery of donepezil hydrochloride (DH) for treating Alzheimer’s disease. The primary aim of this study was to develop polyvinyl alcohol and polyvinyl pyrrolidone blended hydrogels and to evaluate their feasibility for delivering DH via a transdermal route. Physicochemical properties, such as gel fraction (%), swelling ratio (%), weight loss (%), mechanical strength, elongation at break, and Young’s modulus of the prepared hydrogels were evaluated. Furthermore, in vitro skin permeation and in vivo pharmacokinetic studies were performed. With an increased concentration of propylene glycol (PG), the gel fraction (%), maximum strength, and elongation at break decreased. However, the swelling ratio (%) and weight loss (%) of hydrogels increased with increased PG content. The 26% PG-hydrogel was superior, with an enhancement ratio of 12.9 (*** p < 0.001). In addition, the 11% PG-hydrogel and 1% PG-hydrogel exhibited an enhancement ratio 6.30-fold (*** p < 0.001) and 2.85-fold (* p < 0.05) higher than that exhibited by control, respectively, indicating a promising effect of PG on skin permeation. In addition, in vivo pharmacokinetic studies on hairless rats assessed the expediency for transdermal delivery of DH. The transdermal delivery of optimized hydrogel-patches with two different doses of DH revealed that the maximum plasma concentration and area under the curve were dose dependent, and the time to reach the maximum concentration was 8 h. Thus, optimized hydrogels have the potential to enhance the transdermal delivery of DH and could be a novel clinical approach

Eupatilin Inhibits Proliferation of ras-Transformed Human Breast Epithelial (MCF-10A-ras) Cells

Artemisia asiatica Nakai has been used frequently in traditional Asian medicine for the treatment of inflammation and cancer. Eupatilin (5,7-dihydroxy-3',4', 6-trimethoxy-flavone) was shown to be a pharmacologically active ingredient of A asiatica. In the present study, we found that expression of cyclin D1, a key protein that regulates G(1)/S progression, was decreased in MCF-10A-ras cells treated with eupatilin. Downregulation of cyclin D1 expression by eupatifin was accompanied by a reduced expression of c-Jun and the DNA binding activity of the transcription factor AP-1. The expression of p21(waf1/Cip1) was also decreased by eupatilin treatment in both protein and the mRNA levels. We concluded that the inhibitory effect of eupatilin on p21(waf1/Cip1) expression is likely to be associated with the downregulation of cyclin D1 expression and AP-1 activation, which play an important role in the cell cycle arrest of ras-transformed breast epithelial cells

Eupatilin, a Pharmacologically Active Flavone Derived from Artemisia Plants, Induces Apoptosis in Human Gastric Cancer (AGS) Cells

Extracts of Artemisia asiatica Nakai (Asteraceae) possess anti-inflammatory and antioxidative activities. Eupatilin (5,7-dihydroxy-3',4', 6-trimedioxyflavone), one of the pharmacologically active ingredients derived from A. asiatica, was shown to induce apoptosis in human promyelocytic leukemia (HL-60) cells. In the present study, we examined the ability of eupatilin to induce apoptosis in human gastric cancer (AGS) cells. Eupatilin induced the apoptosis of AGS cells as revealed by a decrease in the ratio of pro-apoptotic Bax and anti-apoptotic Bcl-2, as well as the cleavage of caspase-3 and poly(ADP-ribose)polymerase (PARP). The pro-apoptotic effects of eupatilin were further verified by its perturbation of the mitochondrial transmembrane potential (Delta Psi m). In addition, eupatilin treatment led to an elevated expression of p53 and p21. Eupatilin inhibited the activation of ERK1/2 and Akt, which are important components of cell-survival pathways

Beneficial Effects of Evogliptin, a Novel Dipeptidyl Peptidase 4 Inhibitor, on Adiposity with Increased Ppargc1a in White Adipose Tissue in Obese Mice.

Although dipeptidyl peptidase 4 (DPP4) is an adipokine known to positively correlate with adiposity, the effects of pharmacological DPP4 inhibition on body composition have not been fully understood. This study was aimed to assess the effects of DPP4 inhibitors on adiposity for the first time in the established obese mice model. The weight loss effects of multiple DPP4 inhibitors were compared after a 4 week treatment in diet-induced obese mice. In addition, a 2 week study was performed to explore and compare the acute effects of evogliptin, a novel DPP4 inhibitor, and exenatide, a glucagon-like peptide-1 (GLP-1) analogue, on whole body composition, energy consumption, various plasma adipokines and gene expression in white adipose tissue (WAT). After the 4 week treatment, weight loss and blood glucose reductions were consistently observed with multiple DPP4 inhibitors. Moreover, after 2-week treatment, evogliptin dose-dependently reduced whole body fat mass while increasing the proportion of smaller adipocytes. However, insulin sensitivity or plasma lipid levels were not significantly altered. In addition to increased active GLP-1 levels by plasma DPP4 inhibition, evogliptin also enhanced basal metabolic rate without reduction in caloric intake, in contrast to exenatide; this finding suggested evogliptin's effects may be mediated by pathways other than via GLP-1. Evogliptin treatment also differentially increased Ppargc1a expression, a key metabolic regulator, in WAT, but not in skeletal muscle and brown adipose tissue. The increased expression of the downstream mitochondrial gene, Cox4i1, was also suggestive of the potential metabolic alteration in WAT by DPP4 inhibitors. We are the first to demonstrate that pharmacological DPP4 inhibition by evogliptin directly causes fat loss in established obese mice. In contradistinction to exenatide, the fat-loss effect of DPP4 inhibitor is partly attributed to enhanced energy expenditure along with metabolic changes in WAT. These results provide insight into the regulation of energy storage in WAT caused by DPP4 inhibition

Effect of evogliptin treatment on the gene expression in muscle and adipose tissues.

<p>After 2–week administration of exenatide (30 μg kg^-1, once daily, s.c.) or evogliptin at 0.081% (w/w) in HF-DIO mice, (A) PGC-1α (<i>Ppargc1a</i>) gene expression in soleus muscle and two types of fat tissues (interscapular fat and epididymal fat for brown adipose tissue and white adipose tissue, respectively), and gene expression levels of (B) UCP1 (<i>Ucp1</i>), (C) COXIV (<i>Cox4i1</i>) and HIF-1α (<i>Hif1a</i>) were assessed in white adipose tissue by realtime qPCR method (n = 8/group). #, <i>P</i> < 0.05 vs. lean control and *, <i>P</i> < 0.05 vs. HF-DIO control by one-way ANOVA; ‡, <i>P</i> < 0.05 by Student’s t-test.</p

Evogliptin increased energy expenditure unlike exenatide.

<p>HF-DIO mice were treated with exenatide (30 μg kg^-1, once daily, s.c.) or evogliptin at 0.081% (w/w) for 2 weeks. Metabolic parameters were measured using an indirect calorimetry system; (A) Oxygen consumption (VO₂) and carbon dioxide production (VCO₂), (B) mean energy expenditure (EE), (C) respiratory quotient (Rq), and (D) a plot of individual data of total mean EE vs. (lean mass + 0.2 × fat mass) as a covariate (n = 8/group). #, <i>P</i> < 0.05 vs. lean control and *, <i>P</i> < 0.05 vs. HF-DIO control by one-way ANOVA.</p

Two-week treatment of evogliptin decreased whole body fat mass in obese mice.

<p>After HF-DIO mice were treated with exenatide (30 μg kg^-1, once daily, s.c.) or evogliptin at 0.027%, 0.081%, or 0.27% (w/w) for 2 weeks, (A) plasma DPP4 activity, (B) body weight, (C) energy intake, (D) whole body fat mass, (E) lean body mass, and (F) plasma triglycerides levels were determined (n = 8/group). #, <i>P</i> < 0.05 vs. lean control and *, <i>P</i> < 0.05 vs. HF-DIO control by one-way ANOVA; †, <i>P</i> < 0.05 vs. the baseline by RM two-way ANOVA; ‡, <i>P</i> < 0.05 vs. HF-DIO control by Student’s <i>t</i>-test.</p

Evogliptin treatment reduced adipocyte size and distribution.

<p>HF-DIO mice were treated with exenatide (30 μg kg^-1, once daily, s.c.) or evogliptin at 0.027%, 0.081%, or 0.27% (w/w) for 2 weeks. The effects on adipocytes from epididymal fat tissues were histologically determined (three sections/animals, eight animals/group). (A) Representative images (original magnification, ×200), (B) mean adipocyte areas and (C-D) percentile distribution of adipocyte size were presented. #, <i>P</i> < 0.05 vs. lean control and *, <i>P</i> < 0.05 vs. HF-DIO control by one-way ANOVA.</p