Effect of acidity of drugs on the prediction of human oral absorption by biopartitioning micellar chromatography

Biopartitioning micellar chromatography(BMC)is a potentially high throughput and low cost alternative for in vitro prediction of drug absorption,which can mimic the drug partitioning process in biological systems.In this paper,a data set of 56 compounds representing acidic,basic,neutral and amphoteric drugs from various structure classes with human oral absorption(HOA)data available were employed to show the effect of acidity of drugs in oral absorption prediction.HOA was reciprocally correlated to the negative value of the capacity factor(kBMC)determined by BMC at pH 7.4 and 6.5.The relationships between kBMC and the corresponding HOA values of all compounds were rather poor,but the correlations were improved when the acidity of drugs was taken into consideration.Moreover,the proposed models allowed obtaining of good predictive values for both highly and poorly absorbed compounds.It is demonstrated that the constructed models derived from compounds with the same kind of charge property are of more practically meaningful and rigorous.

β-Lactoglobulin stabilized lipid nanoparticles enhance oral absorption of insulin by slowing down lipolysis

Lipid-based nanocarriers have staged a remarkable comeback in the oral delivery of proteins and peptides, but delivery efficiency is compromised by lipolysis. β-Lactoglobulin(β-lg) stabilized lipid nanoparticles, including nanoemulsions(NE@β-lg) and nanocapsules(NC@β-lg), were developed to enhance the oral absorption of insulin by slowing down lipolysis due to the protection from β-lg. Cremophor EL stabilized nanoemulsions(NE@Cre-EL) were prepared and set as a control. The lipid nanoparticles produced mild and sustained hypoglycemic effects, amounting to oral bioavailability of 3.0% ± 0.3%, 7.0% ± 1.1%, and7.7% ± 0.8% for NE@Cre-EL, NE@β-lg, and NC@β-lg, respectively. Aggregation-caused quenching(ACQ)probes enabled the identification of intact nanoparticles, which were used to investigate the in vivo and intracellular fates of the lipid nanoparticles. In vitro digestion/lipolysis and ex vivo imaging confirmed delayed lipolysis from β-lg stabilized lipid nanoparticles. NC@β-lg was more resistant to intestinal lipolysis than NE@β-lg due to the Ca^(2+)-induced crosslinking. Live imaging revealed the transepithelial transport of intact nanoparticles and their accumulation in the liver. Cellular studies confirmed the uptake of intact nanoparticles. Slowing down lipolysis via food proteins represents a good strategy to enhance the oral absorption of lipid nanoparticles and thus co-formulated biomacromolecules.

Enhancement of oral bioavailability and anti-Parkinsonian efficacy of resveratrol through a nanocrystal formulation

Resveratrol(RES),a non-flavonoid polyphenol extracted from a wide variety of plants,exhibits neuroprotective activities against Parkinson’s disease(PD).However,undesirable water solubility of RES reduces its oral bioavailability and demonstrates lowefficacy in blood and brain,thus limiting its application.In present study,a nanocrystal formulation of RES(RES-NCs)was developed to enhance its oral bioavailability and delivery into brain for PD treatment.RES-NCs were fabricated with hydroxypropyl methylcellulose(HPMC)stabilizer via antisolvent precipitation approach.The obtained RES-NCs displayed the particle size of 222.54±1.66 nm,the PDI of 0.125±0.035,the zeta potential of−9.41±0.37mV,and a rapid in vitro dissolution rate.Molecular dynamics simulation of RES and HPMC revealed an interaction energy of−68.09 kJ/mol and a binding energy of−30.98±0.388 kJ/mol,indicating that the spontaneous binding between the two molecules is through van der Waals forces.RES-NCs conferred enhanced cellular uptake as well as improved permeability relative to pure RES.In addition,RES-NCs were able to protect neurons against cytotoxicity induced by MPP+.Meanwhile,RES-NCs exerted no significant toxic effects on zebrafish embryos and larvae,and did not influence their survival and hatching rates.When orally administered to rats,RES-NCs exhibited more favorable pharmacokinetics than pure RES,with higher plasma and brain concentrations.More importantly,MPTP-induced PD mice showed notable improvements in behavior,attenuated dopamine deficiency,and elevated levels of dopamine and its metabolites after the treatment with RES-NCs.Furthermore,immunoblot analysis revealed that the neuroprotective role of RES-NCsmay be at least partially mediated by Akt/Gsk3βsignaling pathway.Taken altogether,RES-NCs can serve as a potential treatment modality for PD,offering means of improving RES oral bioavailability and brain accumulation.

Enhanced digestion inhibition and mucus penetration of F127-modified self-nanoemulsions for improved oral delivery

Self-nanoemulsifying systems(SNEs) have excellent ability to improve the solubility ofpoorly water-soluble drugs(PWSD). However, SNEs are likely to be degraded in gastroin-testinal(GIT) when their surface is recognized by lipase/co-lipase enzyme complex, result-ing in rapid release and precipitation of encapsulated drugs. The precipitates are then cap-tured and removed by intestinal mucus, reducing the delivery efficacy of SNEs. Herein, theamphiphilic polymer Pluronic? F127 was incorporated into long and short-chain triglyc-erides(LCT, SCT) based SNEs to diminish the recognition and therefore minimized theirdegradation by enzymes and clearance by mucus. The SNEs were characterized in termsof particle size, zeta potential and stability. Ex vivo multiple particles tracking studies wereperformed by adding particle solution into fresh rat mucus. Cellular uptake of SNEs wereconducted by using E12 cells, the absorption and distribution in small intestine were alsostudied after oral administration in male Sprague-Dawley(SD) rats. The in vitro digestionrate of SNEs were found to be in following order SCT-SNE > SCT-F127-SNE > LCT-SNE > LCT-F127-SNE. Moreover, the LCT-F127-SNE was found to be most effective in enhancing cellularuptake, resulting in 3.5-fold, 2.1-fold and 1.7-fold higher than that of SCT-SNE, LCT-SNE andSCT-F127-SNE, respectively. After incubating the SNE with E12 cells, the LCT-F127-SNE ex-hibited the highest amount regarding both mucus penetration and cellular uptake, with anuptake amount number(via bicinchoninic acid(BCA) analysis) of 3.5-fold, 2.1-fold and 1.7-fold higher than that of SCT-SNE, LCT-SNE and SCT-F127-SNE, respectively. The in vivo results revealed that orally administered LCT-F127-SNE could significantly increase the bioavailability of Cyclosporine A(CsA), which was approximately 2.43-fold, 1.33-fold and 1.80-fold higher than that of SCT-SNE, SCT-F127-SNE and LCT-SNE, respectively. We address in this work that F127-modified SNEs have potentials to improve oral drug absorption by significantly reducing gastrointestinal enzymatic degradation and simultaneously enhancing mucus penetration.

Therapeutic Effects of Curcumin Nanoemulsions on Prostate Cancer

The therapeutic potential of curcumin(Cur) is hampered by its poor aqueous solubility and low bioavailability. The aim of this study was to determine whether Cur nanoemulsions enhance the efficacy of Cur against prostate cancer cells and increase the oral absorption of Cur. Cur nanoemulsions were developed using the self-microemulsifying method and characterized by their morphology, droplet size and zeta potential. The results showed that the cytotoxicity and cell uptake were considerably increased with Cur nanoemulsions compared to free Cur. Cur nanoemulsions exhibited a significantly prolonged biological activity and demonstrated better therapeutic efficacy than free Cur, as assessed by apoptosis and cell cycle studies. In situ single-pass perfusion studies demonstrated higher effective permeability coefficient and absorption rate constant for Cur nanoemulsions than for free Cur. Our study suggested that Cur nanoemulsions can be used as an effective drug delivery system to enhance the anticancer effect and oral bioavailability of Cur.

索非那新联合坦索罗辛缓释剂治疗男性下尿路症状的疗效与安全性的荟萃分析

We performed a meta-analysis to compare treatment with a combination of solifenacin plus tamsulosin oral controlled absorption system （TOCAS） with placebo or TOCAS monotherapy. The aim of the meta-analysis was to clarify the efficacy and safety of the combination treatments method for lower urinary tract symptoms （LUTS）. We searched for trials of men with LUTS that were randomized to combination treatment compared with TOCAS monotherapy or placebo. We pooled data from three placebo-controlled trials meeting inclusion criteria. Primary outcomes of interest included changes in International Prostate Symptom Score （IPSS） and urinary frequency. We also assessed postvoid residual, maximum urinary flow rate, incidence of urinary retention （UR）, adverse events. Data were pooled using random or fixed effect models for continuous outcomes and the ManteI-Haenszel method to generate risk ratio. Reductions in IPSS storage subscore and total urgency and frequency score （TUFS） were observed with solifenacin 6 mg plus TOCAS compared with placebo （P 〈 0.0001 and P 〈 0.0001, respectively）. Reductions in IPSS storage subscore and TUFS were observed with solifenacin 9 mg plus TOCAS compared with placebo （P= 0.003 and P = 0.0006, respectively）. Reductions in TUFS was observed with solifenacin 6 mg plus TOCAS compared with TOCAS （P = 0.01）. Both combination treatments were well tolerated, with low incidence of UR. Solifenacin 6 mg plus TOCAS significantly improved total IPSS, storage and voiding symptoms compared with placebo. Solifenacin 6 mg plus TOCAS also improved storage symptoms compared with TOCAS alone. There was no additional benefit of solifenacin 9 mg compared with 6 mg when used in combination with TOCAS.