Establishment of LC-MS/MS Method for Determination of GMDTC in Rat Plasma and Its Application in Preclinical Pharmacokinetics.

Sodium (S)-2-(dithiocarboxylato((2S,3R,4R,5R)-2,3,4,5,6-pentahydroxyhexyl)amino)-4(methylthio)butanoate (GMDTC) is the first compound to use cadmium repellent as an indication. In this paper, we established and validated a bioanalytical method for the determination of GMDTC in rat plasma, and used it to determine the drug concentrations in the plasma of rats after intravenous dosing in different genders and dosages. After pretreating the plasma samples with an acetonitrile-water-ammonia solution (70:30:1.25, v/v/v), liquid chromatographic separations were efficiently achieved with a XBridge C18 column using a 5 min gradient system of aqueous ammonium bicarbonate and 95% acetonitrile-water solution (95:5, v/v) as the eluent. The GMDTC and metolazone (internal standard, IS) detection were carried out using high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (LC-MS/MS), monitored at m/z 390.06-324.1 (for the GMDTC, tR: 2.03 min) and m/z 366.0-259.2 (for IS, tR: 3.88 min). The GMDTC was stable under various testing conditions, and this analytical method conforms to the verification standard of biological analysis methods. The half-life (t1/2) was determined to be 0.54-0.65 h for the intravenous, mean distribution volume and clearances were 1.08-2.08 L/kg and 1-3 L/h/kg, respectively. The AUC0-t and AUC0-∞ found after increasing the dosage exhibited a linear relationship with the administered dose. There were no statistically significant differences in the values obtained for the different genders at dosages of 50, 100 and 250 mg/kg, respectively (p > 0.05). This is the first report of a bioanalytical method to quantify GMDTC in rat plasma using LC-MS/MS, which provides useful information for the study of its pharmacological effects and clinical applications.

Optimization of Ultrasonic Cellulase-Assisted Extraction and Antioxidant Activity of Natural Polyphenols from Passion Fruit.

In this paper, ultrasonic cellulase extraction (UCE) was applied to extract polyphenols from passion fruit. The extraction conditions for total phenol content (TPC) and antioxidant activity were optimized using response surface methodology (RSM) coupled with a Box-Behnken design (BBD). The results showed that the liquid-to-solid ratio (X2) was the most significant single factor and had a positive effect on all responses. The ANOVA analysis indicated quadratic models fitted well as TPC with R2 = 0.903, DPPH scavenging activity with R2 = 0.979, and ABTS scavenging activity with R2 = 0.981. The optimal extraction parameters of passion fruit were as follows: pH value of 5 at 30 °C for extraction temperature, 50:1 (w/v) liquid-to-solid ratio with extraction time for 47 min, the experimental values were found matched with those predicted. Infrared spectroscopy suggested that the extract contained the structure of polyphenols. Furthermore, three main polyphenols were identified and quantified by HPLC. The results showed the content of phenolic compounds and antioxidant activity of the optimized UCE were 1.5~2 times higher than that determined by the single extraction method and the Soxhlet extraction method, which indicates UCE is a competitive and effective extraction technique for natural passion fruit polyphenols.

A fast and direct iodide-catalyzed oxidative 2-selenylation of tryptophan.

A metal-free 2-selenylation of tryptophan derivatives is reported, where the use of iodide as the catalyst and oxone as the oxidant is key to obtain high yields. Various functional groups within the di-seleny and the indole ring are tolerated, and no racemization is generally observed.

MicroRNA-144 promotes remote limb ischemic preconditioning-mediated neuroprotection against ischemic stroke via PTEN/Akt pathway.

Ischemic stroke is a refractory disease generally caused by cerebral ischemic injury. Remote ischemic preconditioning (RIPC) caused by transient ischemia and reperfusion of the femoral artery exerts a protective effect on ischemic stroke-induced brain injury. This study was designed to investigate the potential molecular mechanism of RIPC-mediated neuroprotection, namely, the biological effects of microRNA-144 on RIPC in mice with ischemic stroke and its effects on PTEN and Akt signaling pathways. Healthy adult C57BL6 mice were selected for the establishment of middle cerebral artery occlusion (MCAO). One hour before the start, remote ischemic preconditioning of limbs was performed in mice. Brain edema and infarct volume were measured. The expressions of microRNA-144, PTEN, and Akt were measured. The results showed that, compared with MCAO group, the RIPC group protected mice from cerebral ischemia-reperfusion injury, systemic accumulation of inflammatory cytokines, and accelerated apoptosis of parenchymal cells. In RIPC group, PTEN expression decreased, and mir-144 and Akt expression increased. The level of phosphorylated PTEN in the transfected microRNA-144 inhibitor group increased and the level of phosphorylated Akt reduced significantly. In conclusion, our results suggest that microRNA-144 may play a protective role in remote ischemic pretreatment by downregulating PTEN and upregulating Akt, suggesting that microRNA-144 via PTEN/Akt pathway may be of therapeutic significance in ischemic stroke.

Chinese Herbal Formula Ermiao Powder () Regulates Cholinergic Anti-inflammatory Pathway in Rats with Rheumatoid Arthritis.

OBJECTIVE: To investigate the effect of Chinese herbal formula Ermiao Powder (, EMP) on the expression of cholinergic anti-inflammatory pathway in rats with rheumatoid arthritis (RA). METHODS: Seventy-two rats were randomly divided into 6 groups according to body weight, including normal control group, collageninduced arthritis (CIA) group, three doses EMP groups, and methotrexate (MTX) group (n=12 per group). All of the rats except for those in the normal control group were given multipoint subcutaneous injection of bovine type II collagen to establish a CIA model. Three EMP groups received a high- (4.5 g/kg), medium- (3.0 g/kg), and low- (1.5 g/kg) doses of EMP by intragavage, respectively. MTX group was injected intraperitoneally MTX at 0.9 mg/kg once a week as the positive control. The administration was 3 consecutive weeks. Joint swelling, arthritis index, and body weight changes in different experimental groups of rats were tested. The joint damage was evaluated by masson staining. Quantitative real-time polymerase chain reaction, Western blot, and immunohistochemistry (IHC) were performed to evaluate the expression of CHRNA7, encoding α7 nicotinic acetylcholine receptor in the cholinergic anti-inflammatory pathway, in different tissues and their localization in the spleen and joints. RESULTS: CHRNA7 expression levels were significantly higher in the joints and spleens of CIA group than those in normal control group (both P<0.05). Moreover, the CHRNA7 mRNA and protein levels in the spleen and joints of MTX and three doses of EMP groups were significantly lower than CIA group (all P<0.05). Compared with the MTX group, treatment with low-dose EMP resulted in significant reduction of CHRNA7 mRNA and protein expression levels (P<0.05 or P<0.01). IHC showed positive signals of CHRNA7 in the white pulp and red pulp of the spleens of rats; CHRNA7 was expressed on fibroblast-like synoviocytes, macrophages, and endothelial cells in the joints of rats, and the expression in the joints of low-dose EMP group was significantly lower than that in the CIA group (P<0.01). CONCLUSIONS: Cholinergic anti-inflammatory pathway was involved in the generation of the inflammatory reaction in CIA rats, and EMP exerted therapeutic effect on RA through cholinergic anti-inflammatory pathway.

FBW7 protects against spinal cord injury by mitigating inflammation-associated neuronal apoptosis in mice.

Spinal cord injury (SCI) leads to severe and long-lasting neurological disability. Presently, the lack of effective therapies for SCI is largely attributable to an incomplete understanding of its pathogenesis. F-box and WD repeat domain-containing protein 7 (FBW7, also known as FBXW7) is a type of E3 ubiquitin ligase complex, and plays essential roles in regulating different pathological and physiological processes. In this study, we attempted to explore the effects of FBW7 on SCI progression by the in vivo and in vitro experiments. SCI mice showed significantly reduced expression of FBW7 in spinal cord tissues. Promoting FBW7 expression via intrathecal injection of AAV9/FBW7 effectively improved locomotor function in SCI mice. Neuronal death in spinal cords of SCI mice was obviously ameliorated by FBW7 over-expression, along with greatly decreased expression of cleaved Caspase-3. In addition, microglial activation in spinal cord specimens was detected in SCI mice through increasing Iba-1 expression levels, which was, however, attenuated in SCI mice injected with AAV9/FBW7. Additionally, FBW7 over-expression dramatically restrained inflammatory response in spinal cord tissues of SCI mice, as evidenced by the down-regulated expression of tumor necrosis factor-α (TNF-α) and interleukin 1ß (IL-1ß) through blocking the activation of nuclear factor-κB (NF-κB) signaling. These anti-inflammatory effects of FBW7 were confirmed in LPS-stimulated mouse microglial BV2 cells. Finally, our in vitro studies showed that conditional medium (CM) collected from LPS-incubated BV2 cells markedly induced apoptosis in the isolated primary spinal neurons; However, this effect was overtly ameliorated by CM from LPS-exposed BV2 cells over-expressing FBW7. Thus, FBW7-regulated inflammation in microglial cells was involved in the amelioration of neuronal apoptosis during SCI development. Collectively, these findings illustrated that FBW7 expression was down-regulated in spinal cords of SCI mice, and promoting its expression could effectively mitigate SCI progression by repressing microglial inflammation and neuronal death.

Rosmarinic acid ameliorates hypoxia/ischemia induced cognitive deficits and promotes remyelination.

Rosmarinic acid, a common ester extracted from Rosemary, Perilla frutescens, and Salvia miltiorrhiza Bunge, has been shown to have protective effects against various diseases. This is an investigation into whether rosmarinic acid can also affect the changes of white matter fibers and cognitive deficits caused by hypoxic injury. The right common carotid artery of 3-day-old rats was ligated for 2 hours. The rats were then prewarmed in a plastic container with holes in the lid, which was placed in 37°C water bath for 30 minutes. Afterwards, the rats were exposed to an atmosphere with 8% O2 and 92% N2 for 30 minutes to establish the perinatal hypoxia/ischemia injury models. The rat models were intraperitoneally injected with rosmarinic acid 20 mg/kg for 5 consecutive days. At 22 days after birth, rosmarinic acid was found to improve motor, anxiety, learning and spatial memory impairments induced by hypoxia/ischemia injury. Furthermore, rosmarinic acid promoted the proliferation of oligodendrocyte progenitor cells in the subventricular zone. After hypoxia/ischemia injury, rosmarinic acid reversed to some extent the downregulation of myelin basic protein and the loss of myelin sheath in the corpus callosum of white matter structure. Rosmarinic acid partially slowed down the expression of oligodendrocyte marker Olig2 and myelin basic protein and the increase of oligodendrocyte apoptosis marker inhibitors of DNA binding 2. These data indicate that rosmarinic acid ameliorated the cognitive dysfunction after perinatal hypoxia/ischemia injury by improving remyelination in corpus callosum. This study was approved by the Animal Experimental Ethics Committee of Xuzhou Medical University, China (approval No. 20161636721) on September 16, 2017.

A NaI/H2O2-Mediated Sulfenylation and Selenylation of Unprotected Uracil and Its Derivatives.

An efficient iodide-catalyzed/hydrogen peroxide mediated sulfenylation and selenylation of unprotected uracil and its derivatives with simple thiols and diselenides was established. This coupling tolerates a broad variety of functional groups to provide diverse 5-sulfur/selenium-substituted uracil derivatives in good to excellent yields (up to 93%).

The Effect of Carbonic Maceration during Winemaking on the Color, Aroma and Sensory Properties of 'Muscat Hamburg' Wine.

This is the first study on the effect of carbonic maceration on the quality (color, aroma profile and sensory properties) of Muscat Hamburg, contrasting two winemaking procedures used in Tianjin (classical white and red-winemaking techniques). The values of C* (psychometric chroma), a* (measure of redness) and b* (measure of yellowness) were significantly higher (p < 0.01) in the carbonic macerated wine than in red wine. However, there were no visual differences in color, and classical red wine and carbonic macerated wine had similar h (hue angle) values and located in the red region. Thirty-two aromatic compounds were identified and quantified in Muscat Hamburg wines. The content of volatile compounds (6384.97 µg/L) was significantly higher (p < 0.001) in the carbonic macerated Muscat Hamburg wine than in the other kinds of wine. This result led to the carbonic macerated wine having the highest odor activity values (OAVs) and sensory evaluation scores (86.8 points), which correlates with an "excellent" sensory perception. This study demonstrated that carbonic maceration significantly improved the quality of Muscat Hamburg wine based on volatile analysis and sensory evaluation compared with other conventional methods. Therefore, carbonic maceration could be well suited for making Muscat Hamburg wine.

Iodide/H2O2 Catalyzed Intramolecular Oxidative Amination for the Synthesis of 3,2'-Pyrrolidinyl Spirooxindoles.

An ammonium iodide/hydrogen peroxide-mediated intramolecular oxidative amination of 3-aminoalkyl-2-oxindoles was achieved, affording the corresponding 3,2'-pyrrolidinyl spirooxindoles and their 6- or 7-membered analogous in moderate to high yields. This metal-free procedure features very mild reaction conditions, non-toxicity and easily handled hydrogen peroxide as a clean oxidant.