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A novel NIR fluorogenic substrate was rationally designed towards hPL, which can detect endogenous PL in living cells and tissues, and enable visual high-throughput screening of hPL inhibitors.

Background: Zonula occludens-1 (ZO-1) protein ensures cerebrovascular integrity against brain ischemic injury. Hydroxysafflor yellow A (HSYA) is a major ingredient of safflower (Carthamus tinctorius L.) with anti-oxidative activity. Because conventional ROS scavengers display poor reactivity with endogenous ROS, this study investigated whether HSYA protected ZO-1 by targeting the enzymes responsible for ROS generation.Methords: Photothrombotic stroke model was prepared in mice to evaluate the protective effect of HSYA on cerebrovascular endothelium. The molecular regulation was investigated in cultured cerebral microvascular endothelial cells (bEnd.3 cells).Results: Oral administration of HSYA (50 mg/kg) reduced cerebral vascular leakage with ZO-1 protection in mice after stroke, largely due to suppression of ROS-associated inflammation. In LPS-stimulated bEnd.3 cells, HSYA increased the ratio of NAD+/NADH to restore Sirt1 induction, which bound to Von Hippel-Lindau (VHL) to ensure HIF-1α protein degradation. Although both NOX1 and NOX2 isoforms were inducible in endothelial cells, we identified NOX2 as the driving force of ROS production. Chromatin immunoprecipitation and luciferase report gene assay revealed that HIF-1α transcriptionally regulated p47phox and Nox2 subunits for the assembly of NOX2 complex, which was blocked by HSYA treatment, largely by reducing HIF-1α accumulation. Inflammation-associated lipid peroxidation impaired ZO-1 protein, but HSYA treatment attenuated carbonyl modification and thus prevented ZO-1 protein from 20S proteasome-mediated degradation, eventually protecting endothelial integrity. In microvascular ZO-1 deficient mice, we further confirmed that HSYA protected cerebrovascular integrity and attenuated ischemic injury dependent on ZO-1 protection. Conclusions: HSYA blocked HIF-1α/NOX2 signaling cascades to protect ZO-1 from proteasomal degradation, suggesting that targeting NOX2 in endothelium is a potential therapeutic strategy to protect against ischemic brain injury.

The tubers and roots of Aconitum (Ranunculaceae) are widely used as heart medicine or analgesic agents for the treatment of coronary heart disease, chronic heart failure, rheumatoid arthritis and neuropathic pain since ancient times. As a type of natural products mainly extracted from Aconitum plants, Aconitum alkaloids have complex chemical structures and exert remarkable biological activity, which are mainly responsible for significant effects of Aconitum plants. The present review is to summarize the progress of the pharmacological, toxicological, and pharmacokinetic studies of Aconitum alkaloids, so as to provide evidence for better clinical application. Research data concerning pharmacological, toxicological and pharmacokinetic studies of Aconitum alkaloids were collected from different scientific databases (PubMed, CNKI, Google Scholar, Baidu Scholar, and Web of Science) using the phrase Aconitum alkaloids, as well as generic synonyms. Aconitum alkaloids are both bioactive compounds and toxic ingredients in Aconitum plants. They produce a wide range of pharmacological activities, including protecting the cardiovascular system, nervous system, and immune system and anti-cancer effects. Notably, Aconitum alkaloids also exert strong cardiac toxicity, neurotoxicity and liver toxicity, which are supported by clinical studies. Finally, pharmacokinetic studies indicated that cytochrome P450 proteins (CYPs) and efflux transporters (ETs) are closely related to the low bioavailability of Aconitum alkaloids and play an important role in their metabolism and detoxification in vivo.

Rapamycin and its semi-synthetic analogues (rapalogues) are frequently used in combination with other prescribed medications in clinical settings. Although the inhibitory effects of rapalogues on cytochrome P450 enzymes (CYPs) have been well examined, the inhibition potentials of rapalogues on human esterases have not been investigated. Herein, the inhibition potentials and inhibitory mechanisms of six marketed rapalogues on human esterases are investigated. The inhibitory effects of six marketed rapalogues (rapamycin, zotarolimus, temsirolimus, everolimus, pimecrolimus and tacrolimus) on three major esterases, including human carboxylesterases 1 (hCES1A), human carboxylesterases 2 (hCES2A) and butyrylcholinesterase (BuChE), were assayed using isozyme-specific substrates. Inhibition kinetic analyses and docking simulations were performed to investigate the inhibitory mechanisms of the rapalogues with strong hCES2A inhibition potency. Zotarolimus and pimecrolimus displayed strong inhibition of human hCES2A but these agents did not inhibit hCES1A or BuChE. Further investigation demonstrated that zotarolimus could strongly inhibit intracellular hCES2A in living HepG2 cells, with an estimated IC50 value of 4.09 µM. Inhibition kinetic analyses revealed that zotarolimus inhibited hCES2A-catalyzed fluorescein diacetate hydrolysis in a mixed manner, with the Ki value of 1.61 µM. Docking simulations showed that zotarolimus could tightly bind on hCES2A at two district ligand-binding sites, consistent with its mixed inhibition mode. Our findings demonstrate that several marketed rapalogues are potent and specific hCES2A inhibitors, and these agents can serve as leading compounds for the development of more efficacious hCES2A inhibitors to modulate the pharmacokinetic profiles and toxicity of hCES2A-substrate drugs (such as the anticancer agent irinotecan).

Human carboxylesterase 2 (hCES2A), one of the major serine hydrolases distributed in the small intestine, plays a crucial role in hydrolysis of ester-bearing drugs. Accumulating evidence has indicated that hCES2A inhibitor therapy can modulate the pharmacokinetic and toxicological profiles of some important hCES2A-substrate drugs, such as the anticancer agent CPT-11. Herein, a series of indanone–chalcone hybrids are designed and synthesized to find potent and highly selective hCES2A inhibitors. Inhibition assays demonstrated that most indanone–chalcone hybrids displayed strong to moderate hCES2A inhibition activities. Structure-hCES2A inhibition activity relationship studies showed that introduction of a hydroxyl at the C4’ site and introduction of an N-alkyl group at the C6 site were beneficial for hCES2A inhibition. Particularly, B7 (an N-alkylated 1-indanone–chalcone hybrid) exhibited the most potent inhibition on hCES2A and excellent specificity (this agent could not inhibit other human esterases including hCES1A and butyrylcholinesterase). Inhibition kinetic analyses demonstrated that B7 potently inhibited hCES2A-mediated FD hydrolysis in a mixed inhibition manner, with a calculated Ki value of 0.068 μM. Furthermore, B7 was capable of inhibiting intracellular hCES2A in living cells and displayed good metabolic stability. Collectively, our findings show that indanone–chalcone hybrids are good choices for the development of hCES2A inhibitors, while B7 is a promising candidate for the development of novel anti-diarrhea agents to ameliorate irinotecan-induced intestinal toxicity.

Human Carboxylesterase 2A (hCES2A), one of the most important serine hydrolases, plays crucial roles in the hydrolysis and the metabolic activation of a wide range of esters and amides. Increasing evidence has indicated that potent inhibition on intestinal hCES2A may reduce the excessive accumulation of SN-38 (the hydrolytic metabolite of irinotecan with potent cytotoxicity) in the intestinal tract and thereby alleviate the intestinal toxicity triggered by irinotecan. In this study, more than sixty natural alkaloids have been collected and their inhibitory effects against hCES2A are assayed using a fluorescence-based biochemical assay. Following preliminary screening, seventeen alkaloids are found with strong to moderate hCES2A inhibition activity. Primary structure–activity relationships (SAR) analysis of natural isoquinoline alkaloids reveal that the benzo-1,3-dioxole group and the aromatic pyridine structure are beneficial for hCES2A inhibition. Further investigations demonstrate that a steroidal alkaloid reserpine exhibits strong hCES2A inhibition activity (IC50 = 0.94 μM) and high selectivity over other human serine hydrolases including hCES1A, dipeptidyl peptidase IV (DPP-IV), butyrylcholinesterase (BChE) and thrombin. Inhibition kinetic analyses demonstrated that reserpine acts as a non-competitive inhibitor against hCES2A-mediated FD hydrolysis. Molecular docking simulations demonstrated that the potent inhibition of hCES2A by reserpine could partially be attributed to its strong σ-π and S-π interactions between reserpine and hCES2A. Collectively, our findings suggest that reserpine is a potent and highly selective inhibitor of hCES2A, which can be served as a promising lead compound for the development of more efficacious and selective alkaloids-type hCES2A inhibitors for biomedical applications.

Summary Purpose With the growing popularity of upper lid blepharoplasty, there have been increasing reports of unsatisfactory outcomes that have necessitated a revision surgery. This study aimed to evaluate aesthetic outcomes of surgical correction of the high eyelid fold using a pretarsal orbicularis oculi flap and to highlight the key practice points of this surgical procedure in secondary blepharoplasty. Methods A retrospective study of 31 consecutive Chinese patients who underwent revision surgeries between January 2013 and December 2015 was undertaken through a review of medical records. All these patients underwent surgical correction of high eyelid folds using a pretarsal orbicularis oculi flap, with postoperative follow-up ranging from 6 months to 4 years. Postoperative outcomes were reviewed, evaluated, and analyzed. Results In this study of 31 women who underwent secondary revision procedure of the high eyelid fold using a pretarsal orbicularis oculi muscle flap, mean follow-up time was 8.2 (range 6–48) months. All flaps survived without significant complications. There was no reported incidence of hematoma or infection in early postoperative complications. Clinical effectiveness was satisfactory in most of the patients who underwent fold repair (26/31, 83.9%). However, five patients (16.1%) expressed dissatisfaction with postoperative outcomes; of them, four patients (12.9%) had mild asymmetry, whereas surgical revision was required in only one patient (3.2%). Conclusion Secondary blepharoplasty to correct the high eyelid fold is a challenging procedure for plastic surgeons. Use of the pretarsal orbicularis oculi muscle flap for correction of the high eyelid fold is safe and effective, with better biomechanics and a satisfying aesthetic outcome. This provides a novel treatment option in limited secondary revision techniques.

As a high incidence of chronic inflammatory skin disease, acne has a complex etiology and pathogenesis, and microbial colonization is currently considered as one of the important causes. Therefore, in this paper metagenomics data is analyzed using Frequent-Pattern Growth (FP-Growth) method for aided diagnosis of acne disease. The main ideas include that firstly, the data sets are transformed into binary form of 0 or 1. The original data of lipids whose component content is 0 is set 0, and the original data of lipids whose component content is not 0 is set 1. Then the data sets are scanned to build a frequent pattern tree (FP-tree) based on the frequency of each element and support. Finally, FP-tree is used to determine frequent itemsets. The element items in frequent itemsets correspond to the lipids which are highly correlated with the corresponding data. Experimental results on dataset including normal control (NC), acne healthy skin (HS) and acne diseased skin (DS) show that the proposed method can determine the frequent itemsets of different sample sets. Lipids that can distinguish different skin states are also determined by comparing the difference of frequent itemsets, which can provide guiding help for the auxiliary analysis and treatment of skin acne.

The study was to establish a population pharmacokinetic (PPK) model of piperacillin (PIP) and tazobactam (TAZ) that explain pharmacokinetic variability and to propose optimized dosage regimens in patients with nosocomial infections. In total, 310 PIP and 280 TAZ concentration–time points were collected at steady state over multiple dosing intervals from 50 patients who received PIP/TAZ infused within 30 min or over 3 h. Drug analysis was performed by high-performance liquid chromatography (HPLC). Nonlinear mixed effects modeling was employed to develop PPK model and 1000 Monte Carlo simulation was used to predict the probability of target attainment (PTA) with a target time of non-protein-bound concentration above MIC > 50 % of the dosing interval. A model with one-compartment model had the best predictive performance for the PPK model. The population estimates of PIP were 13.8 L/h (31.1 %) for clearance (CL) and 21.7 L (38 %) for volume of distribution (V). The population estimates of TAZ were 9.3 L/h (29.1 %) for CL and 16 L (35.3 %) for V. Influence of creatinine clearance (CLcr) and body weight were identified as important covariates for PIP/TAZ CL and V, respectively. A 30-min infusion of 4 g every 6 h achieved robust (≥90 %) PTAs for MIC ≤ 16 mg/L. As an alternative mode of administration, a 3-h infusion of 4 g every 6 h achieved robust PTAs for Pseudomonas aeruginosa and Klebsiella pneumoniae. Prolonged infusions achieved better PTAs compared with shorter infusions at similar daily doses. This benefit was most pronounced for MICs between 16 and 40 mg/L.

The herbal medicine Tong Luo Jiu Nao (TLJN) contains geniposide (GP) and ginsenoside Rg1 at a molar ratio of 10:1. Rg1 is the major component of another herbal medicine, panax notoginseng saponin (PNS). TLJN has been shown to strengthen brain function in humans, and in animals it improves learning and memory. We have previously shown that TLJN reduces amyloidogenic processing in Alzheimer's disease (AD) mouse models. Together this suggests TLJN may be a potential treatment for patients with dementia. Because chronic damage of the central nervous system by formaldehyde (FA) has been presented as a risk factor for age-associated cognitive dysfunction, in the present study we investigated the protective effect of both TLJN and GP in neuron-like cells exposed to FA. FA-exposed murine N2a neuroblastoma cells were incubated with TLJN, its main ingredient GP, as well as PNS, to measure cell viability and morphology, the rate of apoptosis and expression of genes encoding Akt, FOXO3, Bcl2 and p53. The CCK-8 assay, cytoskeletal staining and flow cytometry were used to test cell viability, morphology and apoptosis, respectively. Fluorescent quantitative real-time PCR (qRT-PCR) was used to monitor changes in gene expression, and HPLC to determine the rate of FA clearance. Treatment of N2a cells with 0.09 mmol L(-1) FA for 24 h significantly reduced cell viability, changed cell morphology and promoted apoptosis. Both TLJN and GP conferred neuroprotection to FA-treated N2a cells, whereas PNS, which had to be used at lower concentrations because of its toxicity, did not. Our data demonstrate that TLJN can rescue neuronal damage caused by FA and that its main ingredient, GP, has a major role in this efficacy. This presents purified GP as a drug or lead compound for the treatment of AD.

Background Formaldehyde can induce misfolding and aggregation of Tau protein and β amyloid protein, which are characteristic pathological features of Alzheimer’s disease (AD). An increase in endogenous formaldehyde concentration in the brain is closely related to dementia in aging people. Therefore, the discovery of effective drugs to counteract the adverse impact of formaldehyde on neuronal cells is beneficial for the development of appropriate treatments for age-associated cognitive decline. Methods In this study, we assessed the neuroprotective properties of TongLuoJiuNao (TLJN), a traditional Chinese medicine preparation, against formaldehyde stress in human neuroblastoma cells (SH-SY5Y cell line). The effect of TLJN and its main ingredients (geniposide and ginsenoside Rg1) on cell viability, apoptosis, intracellular antioxidant activity and the expression of apoptotic-related genes in the presence of formaldehyde were monitored. Results Cell counting studies showed that in the presence of TLJN, the viability of formaldehyde-treated SH-SY5Y cells significantly recovered. Laser scanning confocal microscopy revealed that the morphology of formaldehyde-injured cells was rescued by TLJN and geniposide, an effective ingredient of TLJN. Moreover, the inhibitory effect of geniposide on formaldehyde-induced apoptosis was dose-dependent. The activity of intracellular antioxidants (superoxide dismutase and glutathione peroxidase) increased, as did mRNA and protein levels of the antiapoptotic gene Bcl-2 after the addition of geniposide. In contrast, the expression of the apoptotic-related gene - P53, apoptotic executer - caspase 3 and apoptotic initiator - caspase 9 were downregulated after geniposide treatment. Conclusions Our results indicate that geniposide can protect SH-SY5Y cells against formaldehyde stress through modulating the expression of Bcl-2, P53, caspase 3 and caspase 9, and by increasing the activity of intracellular superoxide dismutase and glutathione peroxidase.