Adjuvant anti-angiogenic therapy enhances chemotherapeutic uptake in a murine model of head and neck cancer*

Abstract

Intratumoural metabolic demands result in excessive angiogenic cytokine release leading to unorganised vasculature. Resultant fluid dynamics oppose blood flow and drug penetration due to a marked increase in interstitial fluid hydrostatic pressure. It is hypothesised that anti-angiogenic therapy may function to ‘prune’ vasculature and lead to improved chemotherapeutic penetration. Subcutaneous, OSC19 tumour bearing mice (n?=?5/dose/agent) were administered varying doses of an anti-mouse VEGFR2 (DC101) or an anti-mouse VEGFR3 (31C1) –3 d, –1 d, 0 d, +1 d and +3 d prior to 200?µg of cetuximab fluorescently labelled with IRDye800CW. Fluorescence imaging of tumours was performed 10 d post cetuximab-IRDye800CW dose to monitor therapeutic uptake. Co-administration of dual anti-angiogenic agents at 50–50%, 75–25% and 25–75% using optimal dose and time (–1 d 10?mg/kg anti-VEGFR2 and –1 d 40?mg/kg anti-VEGFR3) was also evaluated. In order to establish vessel normalisation, NG2 (pericyte marker) and CD31 (endothelial cells) ratios were assessed during immunohistochemical staining of tumour sections. Twenty-mg/kg anti-VEGFR3?+?5?mg/kg anti-VEGFR2 significantly (p?<?.0005) reduced tumour size (–73%) compared to control (59%). The 20?mg/kg anti-VEGFR3?+?5?mg/kg anti-VEGFR2 and 30?mg/kg anti-VEGFR3?+?2.5?mg/kg anti-VEGFR2 significantly (p?<?.0004) improved percent-injected cetuximab-IRDye800CW dose/gram tumour tissue compared to other groups. Adjuvant, dual anti-angiogenic therapy targeting VEGFR2 and VEGFR3 significantly enhances tumour chemotherapeutic uptake compared to control.     

Effects of glycyrrhizin on the pharmacokinetics of puerarin in rats

1. Puerarin has been reported to possess a wide range of pharmacological activities. This study investigated the effects of glycyrrhizin on the pharmacokinetics of puerarin in rats.

2. The pharmacokinetics of orally administered puerarin (50?mg/kg) with or without glycyrrhizin pretreatment (100?mg/kg/day for 7?days) were investigated. The plasma concentration of puerarin was determined using a sensitive and reliable LC-MS/MS method. The pharmacokinetics profiles were calculated and compared. Additionally, a Caco-2 cell transwell model was used to investigate the potential mechanism of glycyrrhizin’s effects on the pharmacokinetics of puerarin.

3. The results showed that when the rats were pretreated with glycyrrhizin, the maximum concentration (C_max) of puerarin decreased from 761.25?±?52.34 to 456.32?±?34.75?ng/mL, and the area under the concentration–time curve from zero to infinity (AUC_0–inf) also decreased from 4142.15?±?558.51 to 2503.74?±?447.57?μg·h/L. The oral clearance of puerarin increased significantly from 12.20?±?1.53 to 20.47?±?3.25?L/h/kg (p?4. In conclusion, these results indicated that glycyrrhizin could affect the pharmacokinetics of puerarin, possibly by decreasing the systemic exposure of puerarin by inducing the activity of P-gp.     

Pharmacokinetics of isoforskolin after administration via different routes in guinea pigs

1.?The objective of this study was to characterize the pharmacokinetics of isoforskolin after oral, intraperitoneal and intravenous administration, as well as to compare bioavailability.

2.?Isoforskolin was administered to guinea pigs at a dose of 2?mg/kg. Plasma concentrations were determined by high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (HPLC–ESI–MS/MS) method. The pharmacokinetic parameters were calculated by a noncompartmental method. A compartment model was also adopted to describe the pharmacokinetic profiles.

3.?The pharmacokinetic behavior of intravenously administered isoforskolin was characterized by rapid and extensive distribution (V_z?=?16.82?±?8.42?L/kg) followed by rapid elimination from the body (Cl?=?9.63?±?4.21?L/kg/h). After intraperitoneal administration, isoforskolin was absorbed rapidly (T_max?=?0.12?±?0.05?h). The pharmacokinetic profiles of isoforskolin were similar after intraperitoneal and intravenous administration, except for the concentrations at the initial sampling times. Isoforskolin was also absorbed rapidly following oral dosing; however, the concentration–time data were best fit to a one-compartment model, which was different from that observed after intravenous and intraperitoneal administration. Following intraperitoneal and oral administration, the absolute bioavailability of isoforskolin was 64.12% and 49.25%, respectively.

4.?Isoforskolin is a good candidate for oral administration because of its good oral bioavailability.     

Effects of glycyrrhizin on the pharmacokinetics of asiatic acid in rats and its potential mechanism

Context: Asiatic acid has been reported to possess a wide range of pharmacological activities.

Objective: This study investigates the effects of glycyrrhizin on the pharmacokinetics of asiatic acid in rats and its potential mechanism.

Materials and methods: The pharmacokinetics of orally administered asiatic acid (20?mg/kg) with or without glycyrrhizin pretreatment (100?mg/kg/day for seven days) were investigated using a LC–MS method. Additionally, the Caco-2 cell transwell model and rat liver microsome incubation systems were used to investigate the potential mechanism of glycyrrhizin’s effects on the pharmacokinetics of asiatic acid.

Results: The results showed that the C_max (221.33?±?21.06 vs. 324.67?±?28.64?ng/mL), AUC_0–inf (496.12?±?109.31 vs. 749.15?±?163.95?μg·h/L) and the t_1/2 (1.21?±?0.27 vs. 2.04?±?0.32?h) of asiatic acid decreased significantly (p?p?Discussion and conclusions: In conclusion, these results indicated that glycyrrhizin could decrease the system exposure of asiatic acid, possibly by inducing the activity of P-gp or CYP450 enzyme.     

Effects of triptolide on pharmacokinetics of fenofibrate in rats and its potential mechanism

1. Triptolide and fenofibrate are often used together for the treatment of nephrotic syndrome in Chinese clinics.

2. This study investigates the effects of triptolide on the pharmacokinetics of fenofibrate in rats and it potential mechanism.

3. The pharmacokinetics of fenofibrate (20?mg/kg) with or without triptolide pretreatment (2?mg/kg/day for seven days) were investigated. Additionally, the inhibitory effects of triptolide on the metabolic stability of fenofibrate were investigated using rat liver microsome incubation systems.

4. The results indicated that the C_max (35.34?±?7.52 vs. 30.43?±?6.45?μg/mL), t_1/2 (6.17?±?1.15 vs. 4.90?±?0.82?h) and AUC_(0–t) (468.12?±?35.84 vs. 416.35?±?32.68?mg?h?L^?1) of fenofibric acid decreased significantly (p?<?.05). The T_max of fenofibric acid increased significantly (p?<?.05) from 5.12?±?0.36 to 6.07?±?0.68?h. Additionally, the metabolic stability of fenofibrate was prolonged from 35.8?±?6.2 to 48.6?±?7.5?min (p?<?.05) with the pretreatment of triptolide.

5. In conclusion, these results indicated that triptolide could affect the pharmacokinetics of fenofibric acid, possibly by inhibiting the metabolism of fenofibrate in rat liver when they were co-administered.

     

Effects of triptolide on pharmacokinetics of amlodipine in rats by using LC–MS/MS

Context: Triptolide and amlodipine are often simultaneously used for reducing urine protein excretion after renal transplantation in China clinics.

Objective: This study investigated the effects of triptolide on the pharmacokinetics of amlodipine in male Sprague–Dawley rats.

Materials and methods: The pharmacokinetics of amlodipine (1?mg/kg) with or without triptolide pre-treatment (2?mg/kg/day for seven?days) were investigated using a sensitive and reliable LC–MS/MS method. Additionally, the inhibitory effects of triptolide on the metabolic stability of amlodipine were investigated using rat liver microsome incubation systems.

Results: The results indicated that when the rats were pre-treated with triptolide, the C_max of amlodipine increased from 13.78?±?3.57 to 19.96?±?4.56?ng/mL (p?T_max increased from 4.04?±?1.15 to 5.89?±?1.64?h (p?AUC_0–t increased by approximately 104% (p?p?Conclusions: In conclusion, these results indicated that triptolide could affect the pharmacokinetics of amlodipine, possibly by inhibiting the metabolism of amlodipine in rat liver when they are co-administered.     

Influence of grapefruit juice on pharmacokinetics of triptolide in rats grapefruit juice on the effects of triptolide

1.?Triptolide, a major pharmacological component isolated from Tripterygium wilfordii Hook F (TWHF), is a substrate of both CYP3A4 and P-glycoprotein (P-gp).

2.?This study investigates the effects of GFJ on the pharmacokinetics of triptolide in rats.

3.?The pharmacokinetics of orally administered triptolide with or without GFJ pretreatment were investigated. A mechanistic study was also undertaken using the Caco-2 cell transwell model and rat liver microsomes incubation systems to support the in vivo pharmacokinetic data.

4.?The results indicated that coadministration of GFJ could increase the systemic exposure of triptolide significantly, including area under the curve (828.58?±?79.72 versus 541.53?±?45.23?ng·h/mL) and maximum plasma concentration (273.58?±?27.98 versus 193.67?±?10.08?ng/mL). The apparent permeability of triptolide across the Caco-2 cell transwell model increased significantly with the pretreatment of GFJ (from 1.62?±?0.25?×?10^?6 to 2.51?±?0.41?×?10^?6 cm/s), and the metabolic stability of triptolide was also increased from 32.6?±?5.1 to 52.5?±?7.8?min with the pretreatment of GFJ, and the difference was significant (p?5.?In conclusion, GFJ could increase the systemic exposure of triptolide in rats, when GFJ and triptolide was coadministered, and it might work mainly through increasing the absorption of triptolide by inhibiting P-gp, or through slowing down the metabolism of triptolide in rat liver by inhibiting the activity of CYP3A4.     

Cytotoxicity evaluation of electronic cigarette vapor extract on cultured mammalian fibroblasts (ClearStream-LIFE): comparison with tobacco cigarette smoke extract

Abstract

Context: Electronic cigarettes (ECs) are used as alternatives to smoking; however, data on their cytotoxic potential are scarce.

Objective: To evaluate the cytotoxic potential of 21 EC liquids compared to the effects of cigarette smoke (CS).

Methods: Cytotoxicity was evaluated according to UNI EN ISO 10993-5 standard. By activating an EC device, 200?mg of liquid was evaporated and was extracted in 20?ml of culture medium. CS extract from one cigarette was also produced. The extracts, undiluted (100%) and in five dilutions (50%, 25%, 12.5%, 6.25% and 3.125%), were applied to cultured murine fibroblasts (3T3), and viability was measured after 24-hour incubation by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. Viability of less than 70% was considered cytotoxic.

Results: CS extract showed cytotoxic effects at extract concentrations above 12.5% (viability: 89.1?±?3.5% at 3.125%, 77.8?±?1.8% at 6.25%, 72.8?±?9.7% at 12.5%, 5.9?±?0.9% at 25%, 9.4?±?5.3% at 50% and 5.7?±?0.7% at 100% extract concentration). Range of fibroblast viability for EC vapor extracts was 88.5–117.8% at 3.125%, 86.4–115.3% at 6.25%, 85.8–111.7% at 12.5%, 78.1–106.2% at 25%, 79.0–103.7% at 50% and 51.0–102.2% at 100% extract concentration. One vapor extract was cytotoxic at 100% extract concentration only (viability: 51.0?±?2.6%). However, even for that liquid, viability was 795% higher relative to CS extract.

Conclusions: This study indicates that EC vapor is significantly less cytotoxic compared tobacco CS. These results should be validated by clinical studies.     

Influence of Molecular Size on the Retention of Polymeric Nanocarrier Diagnostic Agents in Breast Ducts

Purpose

To investigate the influence of nanocarrier molecular size and shape on breast duct retention in normal rats using a non-invasive optical imaging method.

Methods

Fluorescein-labeled PEG nanocarriers of different molecular weights and shapes (linear, two-arm, four-arm, and eight-arm) were intraductally administered (50?nmol) to female Sprague?CDawley rats. Whole body images were obtained non-invasively. Fluorescence intensities (i.e., amount remaining in duct) were plotted against time to estimate the nanocarrier ductal retention half-lives (t_1/2). Plasma samples were taken and the pharmacokinetics (Tmax, Cmax) of absorbed nanocarriers was also assessed.

Results

The t_1/2 of linear 12, 20, 30, 40, and two-arm 60?kDa nanocarriers were 6.7?±?0.9, 16.1?±?4.1, 16.6?±?3.4, 21.5?±?2.7, and 19.5?±?6.1?h, whereas the four-arm 20, 40, and eight-arm 20?kDa had t_1/2 of 9.0?±?0.5, 11.5?±?1.9, and 12.6?±?3.0?h. The t_1/2 of unconjugated fluorescein was significantly lower (14.5?±?1.4?min). The Tmax for 12, 40, 60?kDa nanocarriers were 1, 24, and 32?h, respectively, and only 30?min for fluorescein.

Conclusions

Since normal breast ducts are highly permeable, the use of nanocarriers may be helpful in prolonging ductal retention of diagnostic and/or therapeutic agents.     

Evaluation of the cytotoxic effect of camptothecin solid lipid nanoparticles on MCF7 cells

Abstract

Camptothecin (CPT) and its analogs exhibit remarkable anti-tumor activity, due to their ability to inhibit DNA topoisomerase I. However, its use is limited by the lack of solubility and stability of the active lactone form. An attractive alternative is the encapsulation of CPT within liposomes. In this study, CPT was incorporated into solid lipid nanoparticles (SLN) based on the triglyceride, Compritol 888 ATO, using supercritical fluid technology without requiring the use of harmful solvents. This drug delivery system was characterized and its cytotoxicity effect was evaluated by measuring MCF7 and MCF10A cell viability as a function of drug loading during a 48-h treatment. Results showed that after 10?h of treatment, MCF7 cells displayed an IC50 of 0.23?±?0.034?μM at a 1:5 (CPT:SLN) loading and 0.22?±?0.027?μM at a 1:10 loading, whereas MCF10A cells displayed an IC50 of 0.40?±?0.036?μM at 1:5 and 0.60?±?0.063?μM at 1:10. On the other hand, the IC50 of free CPT was 0.57?±?0.035?μM and 1.07?±?0.077?μM for MCF7 and MCF10A cells, respectively. Cellular uptake and retention measurements in both cells displayed a two-fold increase when using the SLN formulation. The results from this study showed that the cytotoxic effects of CPT in a SLN formulation improved when compared with those seen with free CPT. The results of this study showed that delivery of CPT as a SLN formulation could be a promising strategy for enhancing its chemotherapeutic effects.     

Effects of Danshen tablets on pharmacokinetics of atorvastatin calcium in rats and its potential mechanism

Context: Danshen tablets (DST), an effective traditional Chinese multi-herbal formula, are often combined with atorvastatin calcium (AC) for treating coronary heart disease in the clinic.

Objective: This study investigated the effects of DST on the pharmacokinetics of AC and the potential mechanism.

Materials and methods: The pharmacokinetics of AC (1?mg/kg) with or without pretreatment of DST (100?mg/kg) were investigated using LC-MS/MS. The effects of DST (50?μg/mL) on the metabolic stability of AC were also investigated using rat liver microsome incubation systems.

Results: The results indicated that C_max (23.87?±?4.27 vs. 38.94?±?5.32?ng/mL), AUC_(0–t) (41.01?±?11.32 vs. 77.28?±?12.92?ng h/mL), and t_1/2 (1.91?±?0.18 vs. 2.74?±?0.23?h) decreased significantly (p?t_1/2) of AC was also decreased (25.7?±?5.2 vs. 42.5?±?6.1) with the pretreatment of DST.

Discussion and conclusions: This study indicated that the main components in DST could accelerate the metabolism of AC in rat liver microsomes and change the pharmacokinetic behaviors of AC. So these results showed that the herb-drug interaction between DST and AC might occur when they were co-administered. Therefore, the clinical dose of AC should be adjusted when DST and AC are co-administered.     

Vincristine and ɛ-viniferine-loaded PLGA-b-PEG nanoparticles: pharmaceutical characteristics,cellular uptake and cytotoxicity

The objective of this study was to prepare the ?-viniferine and vincristine-loaded PLGA-b-PEG nanoparticle and to investigate advantages of these formulations on the cytotoxicity of HepG2 cells. Prepared nanoparticle has shown a homogeneous distribution with 113?±?0.43?nm particle size and 0.323?±?0.01 polydispersity index. Zeta potential was determined as ?35.03?±?1.0?mV. The drug-loading percentages were 6.01?±?0.23 and 2.01?±?0.07 for ?-viniferine and vincristine, respectively. The cellular uptake efficiency of coumarin-6-loaded nanoparticles was increased up to 87.8% after 4?h. Nanoparticles loaded with high concentrations of both drugs showed a cytotoxic effect on HepG2 cells, having the percentage of cell viability of between 43.23% and 47.37%. Unfortunately, the percentage of apoptotic cells after treated with drugs-loaded nanaoparticles (10.93%) was similar to free forms of drugs (12.1%) that might be due to low ?-viniferine release in biological pH at 24?h.     

Effects of verapamil on the pharmacokinetics of puerarin in rats

Abstract

1. The oral bioavailability of puerarin is poor which hindered its clinical performance.

2. This study investigates the effects of verapamil on the pharmacokinetics of puerarin in rats.

3. The pharmacokinetics of orally administered puerarin (50?mg/kg) with or without verapamil pretreatment (10?mg/kg/day for 7?days) were investigated. The plasma concentration of puerarin was determined using LC-MS/MS method, and the pharmacokinetics profiles were calculated and compared. Caco-2 cell transwell model was also used to investigate the effects of verapamil on the transport pf puerarin.

4. The results showed that when the rats were pretreated with verapamil, the maximum concentration (C_max) of puerarin increased from 683.7?±?51.2 to 933.5?±?75.8?ng/mL (p?<?0.05), and the area under the concentration-time curve from zero to infinity (AUC_0-inf) also increased from 3687.3?±?444.6 to 5006.1?±?658.6?μg·h/L (p?<?0.05). The Caco-2 cell transwell experiments indicated that verapamil could decrease the efflux ratio of puerarin from 1.90 to 1.19 through inhibiting the activity of P-gp.

5. In conclusion, these results indicated that verapamil could affect the pharmacokinetics of puerarin, possibly by increasing the systemic exposure of puerarin by inhibiting the activity of P-gp.

     

Antidiabetic,antioxidant, and TNF-α lowering properties of extract of the traditionally used plant Ixeris gracilis in alloxan-induced diabetic mice

Abstract

Context: Ixeris gracilis DC. Stebbins (Asteraceae) is a plant considered to be medicinal by local communities of Meghalaya, India.

Objective: To evaluate the antidiabetic potential, antioxidant activity, and effect of the 80% methanolic extract of the leaves of Ixeris gracilis on tumor necrosis factor-α (TNF-α) expression.

Materials and methods: Varying doses (250–1000?mg/kg body weight) were administered intraperitoneally to normoglycemic mice and their hypoglycemic properties noted for 24?h; the optimum dose observed was used to evaluate its antihyperglycemic activity and effect on glucose tolerance. In vitro antioxidant activity was analyzed by assessing the DPPH radicals scavenging ability of the extract and the total polyphenols, flavonoid, carbohydrate, and protein contents were determined. Diabetic mice were then subjected to daily intraperitoneal injections of the extract for 12 days after which the antioxidant enzyme activities in the tissues were assayed and serum TNF-α was evaluated by ELISA.

Results: The extract displayed varying hypoglycemic activity. The dose of 250?mg/kg body weight exhibited potent antihyperglycemic activity and improved glucose tolerance. The extract was able to scavenge free radicals (IC₅₀ 57.544?µg/ml) and contained polyphenol (76.269?±?0.204?mg GAE/g dry wt), flavonoid (70.070?±?0.626?mg rutin equivalent/g dry wt), protein (4.368?±?8.916?mg/g dry wt), and carbohydrate (558.189?±?0.002?mg/g dry wt). TNF-α level and overall activity of glutathione peroxidase and superoxide dismutase in the liver, kidney, and brain of extract-treated diabetic mice were improved.

Conclusion: The study supports the inclusion of Ixeris gracilis in the list of plants with antidiabetic potential.     

Effects of garlic polysaccharide on alcoholic liver fibrosis and intestinal microflora in mice

Context: Alcoholic liver fibrosis (ALF) is treatable and reversible consequence of liver disease. Intestinal microflora plays an important role in the progression of liver disease. Garlic (Allium sativum L. [Amaryllidaceae]) has been consumed as a traditional medicine to treat liver injury.

Objective: To investigate the effects of garlic polysaccharide (GP) on ALF and intestinal microflora in mice.

Materials and methods: KM mice were orally administered with alcohol (56%, 6?mL/kg) for 30?d to establish ALF model, and divided into four groups together with control group (water only). Hugan tablet (60?mg/kg) or GP (250 and 150?mg/kg) were given 5?h after each dose of alcohol. Biochemical markers in serum and liver homogenate were determined with kits. Alteration of intestinal microflora, and protein expressions of TGF-β1, TNF-α and decorin were detected.

Results: In GP-H group, ALT and AST decreased to 18.85?±?4.71?U/L and 40.84?±?7.89?U/L. MDA, TC, TG and LDL-C decreased to 2.32?±?0.86?mmol/mg, 0.21?±?0.12?mmol/L, 0.96?±?0.31?mmol/L and 0.084?±?0.027?mmol/L. SOD, GSH-Px and GSH increased to 118.32?±?16.32?U/mg, 523.72?±?64.20?U/mg and 0.56?±?0.05?mg/g. Ratios of TGF-β1 and TNF-α decreased to 0.608?±?0.170 and 1.057?±?0.058, decorin increased to 2.182?±?0.129. Lachnospiraceae and Lactobacillus increased, Facklamia and Firmicutes decreased with GP pretreatment.

Discussion and conclusions: Intestinal microflora provides novel insight into the mechanisms of GP that may be used to treat ALF and intestinal microflora dysbiosis.     

Population pharmacokinetics of busulfan in Saudi pediatric patients undergoing hematopoietic stem cell transplantation

Background Busulfan is an antineoplastic drug that is used widely as part of a conditioning regimen in pediatric patients undergoing hematopoietic stem cell transplantation. It has a narrow therapeutic index and highly variable pharmacokinetics; therefore therapeutic drug monitoring is recommended to optimize busulfan dosing. Objective To study the population pharmacokinetics of busulfan in Saudi pediatric patients to optimize its dosing. Settings King Abdullah Specialist Children’s Hospital in Riyadh, Saudi Arabia. Methods This pharmacokinetic observational study was conducted between January 2016 and December 2018. All pediatric patients receiving IV busulfan and undergoing routine therapeutic drug monitoring were included. Population pharmacokinetics modeling was conducted using Monolix2019R1. Pharmacokinetic data of busulfan in children. Results The study included 59 patients and 513 samples. The mean?±?SD age was 6.10?±?3.17 years, and the dose administered was 0.994?±?0.15 mg/kg. The mean?±?SD Cmax and area under the curve (AUC) were 900.60?±?402.8 ng/mL and 1031.14?±?300.75 µM min, respectively. Based on our simulations, the European Medicines Agency recommended dose were adequate for most patient’s groups to achieve the conventional target of an AUC_0–tau of 900–1350 µM min. For patients in the lower weight group <?9 kg, higher doses were need at 1.2 mg/kg. With regards to the newly proposed target of AUC 78–101 mg h/mL, all of the doses we tested had low probability of achieving it. Conclusions Most of our patients had less than a proportional increase in busulfan concentration suggesting autoinduction. The high interindividual variability and autoinduction make dose adjustments challenging and AUC at steady state difficult to predict from the first dose. One approach to improve dose predictions is to use Bayesian dosing software. Based on our simulations, the European Medicines Agency recommended doses were adequate for most patient groups, except those in the lower (<?9 kg) and higher weight groups (>?34 kg).

     

Pharmacokinetics of thiamphenicol glycinate and its active metabolite by single and multiple intravenous infusions in healthy Chinese volunteers

Abstract

1.?The aim of this study was to investigate the pharmacokinetics of thiamphenicol glycinate (TG) and thiamphenicol (TAP) after intravenous (i.v.) infusion of TG hydrochloride in healthy Chinese by evaluating the pharmacokinetic parameters, to provide clinical guidance in TG application.

2.?In this double-blinded, phase I clinical trial, 24 healthy Chinese volunteers were recruited and divided into three groups which received a single dose of 500, 1000 or 1500?mg TG hydrochloride. Subjects in 500?mg group received further administrations at the same dose every 12?h for 5 days. The pharmacokinetic parameters were fitted on the basis of bi-phasic or tri-phasic plasma concentration–time profiles of TG and TAP.

3.?Following a single dose of 500, 1000, 1500?mg TG hydrochloride, the AUC_0–∞ of TG and TAP was 849.1?±?100.3, 1305.2?±?301.8, 2315.9?±?546.9 and 4509.0?±?565.9, 7506.5?±?1112.4, 12?613.3?±?2779.8?µgmL^?1?min, respectively. The total clearance of TG was calculated as 0.58?±?0.07, 0.41?±?0.10 and 0.68?±?0.18?L?min^?1. The transformed rate constant from TG to TAP was fitted as 0.153, 0.113 and 0.118?min^?1, respectively. TAP was mainly excreted as unchanged form with no tendency of accumulation via kidney (71.9?±?19.4%) with the renal clearance estimated at 0.097?L?min^?1.

4.?The established modeling was applied successfully to evaluate the pharmacokinetics of TG and TAP, providing meaningful guidance in TG clinical application.     

Sulforaphane-decorated gold nanoparticle for anti-cancer activity: in vitro and in vivo studies

This study aims to develop sulforaphane-loaded gold nanoparticles (SFN-GNPs) as a potential nanomedicine against the solid tumors. Citrate-mediated electrolysis optimized by four-factor three-level Box-Behnken experimental design was used to get nanoparticles of size <200?nm. The formulation was characterized and evaluated for cytotoxicity B16-F10, MCF-7, SW-620 and Caco-2 cell line. Single dose oral pharmacokinetics, gamma scintigraphy-based bio-distribution and tumor regression studies were conducted to evaluate the in vivo performance. Optimized SFN-GNPs showed spherical morphology with a particle size of 147.23?±?5.321?nm, the zeta potential of ?12.7?±?1.73?mV, entrapment efficiency of 83.17?±?3.14% and percentage drug loading of 37.26?±?2.33%. With SFN-GNPs, both SFN (75.99?±?2.36%) and gold (58.11?±?2.48%) were able to permeate through the intestinal wall in 48?h. SFN-GNPs were able to bring LC₅₀ of <100?µg/ml in all the cytotoxicity assays, more than 5-fold increase in AUC_0?t, enhanced retention at tumor site as well as significant pre-induction tumor growth inhibition and post-induction tumor reduction as compared to plain SFN solution.     

Nanoparticle-based delivery enhances anti-inflammatory effect of low molecular weight heparin in experimental ulcerative colitis

Epithelial administration of low molecular weight heparin (LMWH) has proven its therapeutic efficiency in ulcerative colitis (UC) but still lacks of a sufficiently selective drug delivery system. Polymeric nanoparticles were used here not only to protect LMWH from intestinal degradation but also to provide targeted delivery to inflamed tissue in experimental colitis mice. LMWH was associated with polymethacrylate nanoparticles (NP) type A (PEMT-A) or type B (PEMT-B) of a size: 150?nm resulting in a maximum drug loading: 0.1?mg/mg. In a lipopolysaccharide-stimulated macrophages both, free LMWH and LMWH-NP have significantly reduced the cytokines secretion independently from cellular uptake. The in-vivo therapeutic efficiency was dose dependent as at low doses (100?IU/kg) only minor differences between free LMWH and LMWH-NP were found and the superiority of LMWH-NP became prominent with dose increase (500?IU/kg). Administration of LMWH-NP at 500?IU/kg has markedly improved the clinical activity as compared to LMWH while similarly pathophysiological indicators revealed increased therapeutic outcome in presence of NP compared to LMWH alone: Myeloperoxidase (Colitis control: 10 480?±?5335, LMWH-PEMT-A NP: 1507?±?2165, LMWH-PEMT-B NP: 382?±?143, LMWH: 8549?±?5021 units/g) and tumor necrosis factor: (Colitis control: 1636?±?544, LMWH-PEMT-A NP: 511?±?506, LMWH-PEMT-B NP: 435?±?473, LMWH: 1110?±?309?pg/g). Associating LMWH with NP is improving the anti-inflammatory efficiency of LMWH in-vivo by its protection against degradation in luminal environment and selective drug delivery. Such a combination holds promise for a highly specific therapy by its double selectivity towards the inflamed intestinal tissue. LMWH-PEMT NP have significantly improved the clinical activity in-vivo in comparison to free LMWH.     

PEG-derivative effectively modifies the characteristics of indomethacin-PLGA microspheres destined to intra-articular administration

The aim of this study was to obtain biodegradable indomethacin microspheres for intra-articular administration in rheumatoid arthritis, where angiogenic processes are involved. Indomethacin concentrations to achieve an anti-angiogenic effect would be five-times higher than an anti-inflammatory. Microspheres were prepared by solvent evaporation using PLGA. Indomethacin is a poor water-soluble drug with it being possible that dissolved and non-dissolved drug co-exist within the polymeric matrix resulting in rapid release. To control this release, an oil-PEG-derivative was incorporated, producing changes in morphology, crystallinity and indomethacin release. To minimize the amount of microspheres administered, a two-factor five-level central rotable composite 2²?+?star design was employed with two independent variables: indomethacin percentage and PEG-derivative percentage. The optimum formulation showed mean encapsulation efficiency of 94.3?±?2.2% and released 7.99?±?0.25?µg indomethacin/day/mg microspheres for 21 days. A dose of 20–50?mg of this formulation could be appropriate to achieve both anti-angiogenic and anti-inflammatory effects. Preliminary cytotoxicity studies performed in rat splenocytes showed an adequate cell viability.