Apple is an important dietary agent for human and apple polyphenols (AP) are the main secondary metabolites of apples. In this study, the protective effects of AP on hydrogen peroxide (H2O2)-induced oxidative stress damage in human colon adenocarcinoma Caco-2 cells were investigated by cell viability, oxidative stress change as well as cell apoptosis. Pre-adding AP could significantly increase the survival rate of H2O2-treated Caco-2 cells. Besides, the activities of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and catalase (CAT) were elevated. While the malondialdehyde (MDA) content which is the major oxidant products of polyunsaturated fatty acids (PUFA) reduced after AP treatment. In addition, AP also suppressed the emergence of DNA fragment and decreased the expression of apoptosis-related protein Caspase-3. These results demonstrated that AP could ameliorate H2O2-induced oxidative stress damage in Caco-2 cells, which could serve as a reference for further studies of apple natural active products and deep study of the anti-oxidative stress mechanism.
Rheumatoid arthritis (RA) is a common autoimmune disease with increased cardiovascular disease risk. Liquiritigenin (LG) is a triterpene with anti-inflammatory properties. Our study aimed to explore the effect of LG on RA and the cardiac complication. Collagen-induced arthritis (CIA) mice with LG treatment exhibited obvious alleviation in histopathological changes, accompanied by the decreased expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-17A in synovium and serum. LG attenuated cartilage destruction by reducing matrix metalloproteinase (MMP)-3 and MMP-13 expression in the synovium of CIA mice. The echocardiography results proved the alleviation of cardiac dysfunction in CIA mice. The electrocardiogram, biochemical, and histochemical analysis proved the cardioprotection effect of LG against RA. The decreased expression of inflammatory factors (TNF-α, IL-1β, and IL-6) and fibrotic markers (fibronectin, Collagen I, and Collagen III) in cardiac tissues of CIA mice further corroborated the attenuation of myocardial inflammation and fibrosis by LG. Mechanistic studies showed that LG could inhibit transforming growth factor β-1 (TGF-β1) and phos-Smad2/3 expression in cardiac tissues of CIA mice. Our study suggested that LG could relieve RA and its cardiac complication probably by inhibiting the TGF-β1/Smad2/3 pathway. All these suggested that LG might be a potential candidate for RA and its cardiac complication therapy.
This study aimed to develop a new and effective application form for the liver surface. We designed a two-layered sheet for the controlled release and local disposition of the anticancer drug, 5-fluorouracil (5-FU), without leakage into the peritoneal cavity. We employed poly(lactic-co-glycolic acid) (PLGA) and hydroxypropyl cellulose (HPC) to form two-layered sheets by attaching a cover sheet and a drug-containing sheet. The prepared two-layered sheets released 5-FU constantly for up to 14 d without any significant leakage from the cover side in vitro. Furthermore, we have applied sheets containing 5-FU to the rat liver surface in vivo. Notably, 5-FU could be detected in the liver attachment region even 28 d after application. The distribution ratio of 5-FU in the attachment region compared to the other liver lobes varied among the sheet formulations with different additive HPC compositions. The area under the liver concentration–time curve (AUC) of 5-FU in the attachment region from 0 to 28 d was the highest in the case of HPC 2% (w/w). This is probably due to the enhanced 5-FU released amount and controlled absorption rate from the liver surface by released HPC. No critical toxic effects were evident by the application of the two-layered sheets from the body weight change and alanine aminotransferase/aspartate aminotransferase (ALT/AST) activities. Consequently, the possible advantage of the two-layered sheets for prolonged retention of a drug in a specific region in the liver was clarified.
Retinoid X receptor (RXR) agonist NEt-3IB (1) is a candidate for the treatment of inflammatory bowel disease (IBD), and we have established a process synthesis of 1 in which the final product is obtained by recrystallization from 70% EtOH. However, we found that there are two crystal forms of 1. Here, to characterize and clarify the relationship between them, we conducted thermogravimetry, powder X-ray diffraction, and single crystal X-ray diffraction. The crystal forms were identified as the monohydrate form I and anhydrate form II. The crystal form I, obtained as a stable form by our established synthesis, was easily dehydrated simply by drying to afford the form II′, which was similar to the crystal form II obtained by recrystallization from anhydrous EtOH. Storage of the form II′ in air regenerated the form I. The molecular conformations of 1 in the crystals of the two forms are similar, and they can be reversibly interconverted. The solubility of the monohydrate form I and anhydrate form II was examined and the former was found to be less soluble than the latter. Thus, form I may be superior to form II for targeting IBD, because of higher delivery to the lower gastrointestinal tract and reduction of systemic side effects associated with lower absorption due to lower water solubility.
Oral disulfiram (DSF) has been used clinically for alcohol dependence and recently has been found to have antitumor activity. A transdermal delivery system would be useful for maintaining drug concentration and reducing the frequency of administration of DSF for cancer treatment. Penetrating the stratum corneum (SC) barrier is a challenge to the transdermal delivery of DSF. Therefore, we investigated the promoting effects and mechanism of action of the combination of oleic acid (OA) and Tween 80 on the skin permeation of DSF. Hairless mouse skin was exposed to OA and Tween 80, combined in various ratios (1 : 0, 2 : 1, 1 : 1, 1 : 2, and 0 : 1). A permeation experiment was performed, and total internal reflection IR spectroscopic measurements, differential scanning calorimetry, and synchrotron radiation X-ray diffraction measurements were taken of the SC with each applied formulation. The combination of OA and Tween 80 further enhanced the absorption-promoting effect of DSF, compared with individual application. The peak of the CH2 inverse symmetric stretching vibration near the skin surface temperature was shifted by a high frequency due to the application of OA, and DSF solubility increased in response to Tween 80. We believe that the increased fluidity of the intercellular lipids due to OA and the increased solubility of DSF due to Tween 80 promoted the absorption of DSF. Our study clarifies the detailed mechanism of action of the skin permeation and promoting effect of DSF through the combined use of OA and Tween 80, contributing to the development of a transdermal preparation of DSF.
Oral disulfiram (DSF) has been used
clinically for alcohol dependence and recently has been found to have antitumor
activity. A transdermal delivery system would be useful for reducing the
frequency of administration of DSF for cancer treatment. The authors found that
the combination of oleic acid (OA) and Tween 80 further enhanced skin
permeation of DSF compared with individual application. The peak of CH2
asymmetric stretching vibration was blue-shifted by the application of OA, and
DSF solubility increased in response to Tween 80. Their study clarified the
detailed mechanism of action of skin permeation and promoting effect of DSF
through the combined use of OA and Tween 80.
The fragment molecular orbital (FMO) method is a fast quantum-mechanics method that divides systems into pieces of fragments and performs ab initio calculations. The method has been expected to improve the accuracy of describing protein-ligand interactions by incorporating electronic effects. In this article, FMO calculation with solvation methods were applied to the affinity prediction at the ATP-binding site of PDHK4. As the ionized aspartic acid lies at the center and is involved in the complex hydrogen bond networks, this system has turned out to be a difficult target to describe by traditional molecular-mechanics method. In the FMO calculation with the polarizable continuum model (PCM) solvation method, a considerable amount of charge (−0.27e) was transferred from the ionized aspartate to the surrounding residues. We found that using FMO with the PCM solvation method was important to increase the correlation, and by incorporating the ligand deformation energy, the correlation was improved to R = 0.81 for whole twelve compounds and R = 0.91 without one outlier compound.
This computational paper describes the
importance of treating electronic effects among hydrogen bond networks. Fragment
Molecular Orbital (FMO) method, which is a fast quantum-mechanics method, was
applied to the affinity prediction at the hydrogen bond networks of PDHK4. Authors
found that the FMO calculation with the solvation method of polarizable
continuum model (PCM) was important to increase the prediction accuracy. A
considerable amount of charge was transferred among the target site in the
FMO/PCM calculation, which was not described in the traditional
molecular-mechanics method. These results highlight the importance of electronic
effects in the affinity prediction toward hydrogen bond networks.
Newly synthesized dehydroxymethyl epoxyquinomycin (DHMEQ) derivatives 6–9, which contain a tertiary hydroxyl group instead of the original secondary hydroxyl group, showed improved solubility in alcohol while maintaining their inhibitory activity against nitric oxide (NO) production, which is used as an indicator of nuclear factor-kappa B (NF-κB) inhibitory activity. We also synthesized a derivative 5 having a cyclopropane ring and a tertiary hydroxyl group and examined its inhibitory activity against NO production. Although it reacted with a nucleophile in a flask, it did not inhibit NO production. The change from a secondary hydroxyl group to a tertiary hydroxyl group contributed to improve the solubility of the compounds while retaining NO inhibitory activity, but had no effect on improving the activity of the cyclopropane form. Compounds in which the secondary hydroxyl group of DHMEQ was converted to a tertiary hydroxyl group would be excellent NF-κB inhibitor candidates because their solubility is improved without decreasing NO inhibitory activity.
The degradation behavior of three benzodiazepines (BZPs)—lormetazepam (LMZ), lorazepam, and oxazepam—with hydroxy groups on the diazepine ring in artificial gastric juice and the effect of storage pH conditions on drug degradability were monitored using an LC/photodiode array detector (PDA) to estimate their pharmacokinetics in the stomach. Although the three BZPs degraded in artificial gastric juice, none could be restored, despite increasing the storage pH, implying that the degradation reaction was irreversible. As for LMZ, we discussed the physicochemical parameters, such as the activation energy and activation entropy involved in the degradation reaction as well as the reaction kinetics; one of the degradation products was isolated and purified for structural analysis. In the LMZ degradation experiment, peaks corresponding to degradation products, (A) and (B), were detected through the LC/PDA measurements. Regarding the degradation behavior, we hypothesized that LMZ was degraded into (B) via (A), where (A) was an intermediate and (B) was the final product. Although the isolation of degradation product (A) was challenging, degradation product (B) could be isolated and was confirmed to be “methanone, [5-chloro-2-(methylamino)phenyl](2-chlorophenyl)-” based on structure determination using various instrumental analyses. The compound exhibited axis asymmetry as determined using single-crystal X-ray structure analysis. Because the formation of degradation product (B) was irreversible, it would be prudent to target the final degradation product (B) and LMZ for identification when detecting LMZ in human stomach contents, such as during forensic dissection.
We unveiled superior base mediators for the annulative condensation of salicylaldehydes and acrylonitrile to give 3-cyano-2H-chromenes, which has been mediated only by 1,4-diazabicyclo[2.2.2]octane (DABCO) over the past two decades. The reactions were most efficiently mediated by 4-dimethylaminopyridine (DMAP), which yielded 3-cyano-2H-chromenes in higher yields than DABCO in most cases. We also confirmed that the reaction remained high yielding in a decagram-scale experiment with a catalytic amount of DMAP. The utility of this reaction was also exemplified by derivatization of an obtained 3-cyano-2H-chromene into a known 2H-chromene-3-carboxylic acid, which was previously synthesized with a non-readily available reagent.