DL-3-n-butylphthalide therapy for Parkinson's disease: A randomized controlled trial.

Currently available treatments for Parkinson's disease (PD) do not delay or prevent disease development and progression. DL-3-n-butylphthalide (NBP), isolated from Apium graveolens seeds, alleviates oxidative damage and mitochondrial dysfunction. It has been revealed to reduce the loss of dopamine neurons in pre-clinical PD models, and has been approved for the treatment of ischemic stroke patients. The purpose of the present study was to examine whether NBP has the capacity provide a benefit for PD patients and to slow disease progression. A randomized, controlled trial was performed between September 2014 and December 2016. Pairs of patients matched by age, gender and off-medication Unified PD Rating Scale motor subscale (UPDRS-III) scores, were randomly assigned to an NBP treatment group and a control group. All patients continued their originally prescribed medication regimen and those in the NBP group were administered NBP at 200 mg three times daily for 24 weeks. Primary outcome measures were changes in UPDRS-III, including tremor score and non-tremor score, the Pittsburgh sleep quality index (PSQI) and the PD 39-items questionnaire (PDQ) scores. Assessments were completed by blinded evaluators at baseline and 12, 24 and 48 weeks after randomization. All patients were monitored for adverse events (AEs). A total of 103 patients were enrolled in the present study. The NBP group exhibited significantly greater improvements in the non-tremor, PSQI and PDQ-39 scores than the control group, which generally exhibited no improvement. NBP-associated AEs were uncommon and primarily consisted of mild gastrointestinal symptoms. In conclusion, over the 6-month treatment period, NBP was safe and effective for improving the symptoms and impairing the progression of patients with PD (Trial registry number, ChiCTR1800018892).

Discovery of Novel Janus Kinase (JAK) and Histone Deacetylase (HDAC) Dual Inhibitors for the Treatment of Hematological Malignancies.

Concurrent inhibition of Janus kinase (JAK) and histone deacetylase (HDAC) could potentially improve the efficacy of the HDAC inhibitors in the treatment of cancers and resolve the problem of HDAC inhibitor resistance in some tumors. Here, a novel series of pyrimidin-2-amino-pyrazol hydroxamate derivatives as JAK and HDAC dual inhibitors was designed, synthesized, and evaluated, among which 8m possessed potent and balanced activities against both JAK2 and HDAC6 with half-maximal inhibitory concentration at the nanomolar level. 8m exhibited improved antiproliferative and proapoptotic activities over SAHA and ruxolitinib in several hematological cell lines. Remarkably, 8m exhibited more potent antiproliferation effect than the combination of SAHA and ruxolitinib in HEL cells bearing JAK2V617F mutation. Pharmacokinetic studies in mice showed that 8m possessed good bioavailability after intraperitoneal administration. Finally, 8m showed antitumor efficacy with no significant toxicity in a HEL xenograft model. Collectively, the results confirm the therapeutic potential of JAK and HDAC dual inhibitors in hematological malignancies and provide valuable leads for further structural optimization and antitumor mechanism study.

Discovery of Novel Pazopanib-Based HDAC and VEGFR Dual Inhibitors Targeting Cancer Epigenetics and Angiogenesis Simultaneously.

Herein a novel series of pazopanib hybrids as polypharmacological antitumor agents were developed based on the crosstalk between histone deacetylases (HDACs) and vascular endothelial growth factor (VEGF) pathway. Among them, one ortho-aminoanilide 6d and one hydroxamic acid 13f exhibited considerable total HDACs and VEGFR-2 inhibitory activities. The HDAC inhibitory activities endowed 6d and 13f with potent antiproliferative activities, which was not observed in the approved VEGFR inhibitor pazopanib. Compounds 6d and 13f possessed comparable HDAC isoform selectivity profiles to the clinical class I HDAC inhibitor MS-275 and the approved pan-HDAC inhibitor SAHA, respectively. 6d and 13f also exhibited uncompromised multiple tyrosine kinases inhibitory activities relative to pazopanib. The intracellular dual inhibition to HDAC and VEGFR of 6d and 13f was validated by Western blot analysis. In both HUVECs tube formation assay and rat thoracic aorta rings assay, 6d and 13f showed comparable antiangiogenic potencies to pazopanib. What's more, 6d possessed desirable pharmacokinetic profiles with the oral bioavailability of 72% in SD rats and considerable in vivo antitumor efficacy in a human colorectal adenocarcinoma (HT-29) xenograft model.

Discovery of a tetrahydroisoquinoline-based HDAC inhibitor with improved plasma stability.

Histone deacetylase inhibitors with desirable pharmacokinetic profiles which can be delivered to solid tumor tissues in large amount might be promising to treat solid tumor effectively. Herein, structural modification of a previously reported tetrahydroisoquinoline-based HDAC inhibitor 1 was carried out to improve its plasma stability for more feasible drug delivery. Among three newly synthesized analogs, the in vitro rat plasma stability of compound 2 (t1/2=630min) was over 5-fold improved than its parent 1 (t1/2=103min). In vitro activity evaluation showed that compound 2 and 1 exhibited similar HDACs inhibitory activity, which was validated by western blot analysis and antiproliferative assay. Moreover, compared with 1, compound 2 exhibited comparable, if not higher, in vivo antitumor activity in a human breast carcinoma (MDA-MB-231) xenograft model.

Preclinical and Clinical Studies of Chidamide (CS055/HBI-8000), An Orally Available Subtype-selective HDAC Inhibitor for Cancer Therapy.

Epigenetic modifications play central roles in cellular differentiation and their deregulations really contribute to tumor development. Histone deacetylase (HDAC) enzymes can exert their functions in the epigenetic regulation of gene expression related to oncogenesis via deacetylating the lysine residues of histones in the chromatin and various non-histone proteins. A majority of HDAC inhibitors (HDACIs) have been in different stages of preclinical and clinical trials with potent anticancer activity recently. Among these agents, chidamide tested as either monotherapeutic agent or in combination regimens for numerous hematological and solid malignancies has shown promising potential as an orally active subtype-selective HDACI. Herein we will highlight the progress of clinical trials of chidamide and rationally analyze those results from both preclinical and clinical studies about chidamide as an epigenetic modulator in cancer therapy.

Enhancing the Sensitivity of Pharmacophore-Based Virtual Screening by Incorporating Customized ZBG Features: A Case Study Using Histone Deacetylase 8.

As key regulators of epigenetic regulation, human histone deacetylases (HDACs) have been identified as drug targets for the treatment of several cancers. The proper recognition of zinc-binding groups (ZBGs) will help improve the accuracy of virtual screening for novel HDAC inhibitors. Here, we developed a high-specificity ZBG-based pharmacophore model for HDAC8 inhibitors by incorporating customized ZBG features. Subsequently, pharmacophore-based virtual screening led to the discovery of three novel HDAC8 inhibitors with low micromole IC50 values (1.8-1.9 µM). Further studies demonstrated that compound H8-A5 was selective for HDAC8 over HDAC 1/4 and showed antiproliferation activity in MDA-MB-231 cancer cells. Molecular docking and molecular dynamic studies suggested a possible binding mode for H8-A5, which provides a good starting point for the development of HDAC8 inhibitors in cancer treatment.

Enhanced anticancer activity of 5-FU in combination with Bestatin: Evidence in human tumor-derived cell lines and an H22 tumor-bearing mouse.

The clinical use of 5-fluorouracil (5-FU) is increasingly limited by low response rates, adverse reactions, and toxicity. A drug combination offers a new strategy for appropriate use of 5-FU. Bestatin, an aminopeptidase N (APN) inhibitor, has been used as an adjuvant chemotherapy drug because of its actions to suppress tumorigenesis and invasion. The current study evaluated the anticancer efficacy of 5-FU plus Bestatin at the cellular and animal level. The combination killed more colonic cancer, hepatic carcinoma, and ovarian cancer cells and fewer nonmalignant human embryonic kidney (HEK293) and Chinese hamster ovary (CHO) cells than 5-FU or Bestatin alone. Moreover, 41.58% of ES-2 and 20.86% of PLC/PRF/5 cell apoptosis was caused by the combination of the two, while 5-FU caused apoptosis of 20.86% of ES-2 cells and 8.85% of PLC/PRF/5 cells. The cell cycle was arrested in the S and G0/G1 phases when a combination of the two was used. In an experiment involving mice bearing tumors, a combination of the two had a rate of tumor inhibition of 61.98%, while 5-FU alone had a rate of tumor inhibition of just 49.17%. In addition, the combination of the two was safer than either drug alone and did not cause weight loss or death. In conclusion, combining 5-FU and Bestatin could enhance the anticancer activity of 5-FU and decrease its cytotoxicity. These results suggest that 5-FU plus Bestatin has greater efficacy as a tumor therapy.

Rapid screening of aminopeptidase N inhibitors by capillary electrophoresis with electrophoretically mediated microanalysis.

In this work, an electrophoretically mediated microanalysis (EMMA) method with a partial-filling technique was setup to evaluate the inhibitory potency of novel compounds toward aminopeptidase N (APN). It was necessary to optimize the electrophoretic conditions with respect to the kinetic constraints and for attaining high sensitivity. In our setup, a part of the capillary was filled with the incubation buffer for the enzyme reaction, whereas the rest was filled with a suitable BGE for the separation of substrates and products. To monitor the performance of the newly developed method, the kinetic constants (Km and Vmax) for the catalyzed dissociation of L-Leucine-p-nitroanilide in the presence of APN as well as the inhibition constant (IC50 ) of a known competitive inhibitor, that is bestatin, were determined and these results were compared with those obtained by a classical spectrophotometric assay. The developed EMMA method was subsequently applied to the screening of 30 APN inhibitors. Whereas the inhibition potency of these inhibitors (expressed in IC50 values) were significantly underestimated by the EMMA method, the order of the inhibitory potential of these various compounds was found in agreement with the literature.

[Effect of Qiling Decoction combined HAART on expression levels of Treg cells and Th17 in HIV/AIDS patients].

OBJECTIVE: To explore the effect of Qiling Decoction (QD) combined highly active antiretroviral treatment (HAART) on expression levels of peripheral blood Th17 and Treg cells in HIV/AIDS patients. METHODS: Totally 55 HIV/AIDS patients were randomly assigned to the treatment group (28 cases) and the combination group (27 cases). Besides, 21 HIV negative patients were recruited as the healthy control group. Those in the treatment group received HARRT alone, while those in the combination group received HAART combined QD. The observation lasted for 24 weeks. Meanwhile, according to peripheral blood CD4+ T cell counts before treatment, HIV/AIDS patients were assigned to three subgroups. For patients in subgroup 1, 1 cells/microL < CD4+ T cell counts < or = 100 cells/microL; For patients in subgroup 2, 101 cells/microL < CD4+ T cell counts < or = 200 cells/lL; For patients in subgroup 3, 201 cells/microL < CD4+ T cell counts < or = 350 cells/microL. Expression of peripheral blood Th17 and Treg cells, and number of CD4+ T cell counts were detected using flow cytometry (FCM)in HIV/AIDS patients at the pre-treatment baseline, week 4, 12, and 24, as well as those in the healthy control group. RESULTS: Compared with the healthy control group, CD4+ T cell counts and the baseline expression level of Th17 cells in the peripheral blood of HIV/AIDS patients significantly decreased, the expression level of Treg cells significantly increased P < 0.01). Compared with before treatment in the same group, CD4+ T cell counts all increased at week 4, 12, and 24 in the two treatment groups, showing statistical difference (P < 0.05, P < 0.01). There was no statistical difference in the effective rate at various CD4+ T cell levels between the two groups (P > 0.05). There was no statistical difference in expression levels of Th17 and Treg cells between the combination group and the treatment group at any time point (all P >0.05). The Th17/Treg ration significantly increased in the combination group after 24 weeks of treatment, showing statistical difference when compared with the treatment group (U = 2.135, P = 0.038). CONCLUSION: QD could improve the immune balance of Th17/Treg cells, which might be one of its mechanisms for improving HIV/AIDS patients' immunity.

Discovery of N-(3-((7H-purin-6-yl)thio)-4-hydroxynaphthalen-1-yl)-sulfonamide derivatives as novel protein kinase and angiogenesis inhibitors for the treatment of cancer: Synthesis and biological evaluation. Part III.

A novel series of N-(3-((7H-purin-6-yl)thio)-4-hydroxynaphthalen-1-yl)-sulfonamides were designed and synthesized. Biological characterization revealed that several compounds exerted enhanced anti-proliferative activity against human umbilical vein endothelial cells (HUVECs) and several cancer cell lines and high specific protein kinase and angiogenesis inhibitory activities. Compared with our previously synthesized compounds, the substitution of sulfonamide structure for amide fragment played an essential role for the advance of inhibitory activities. In addition, the replacement of 1H-1,2,4-triazole ring by 7H-purine did not result in obvious decrease of inhibition efficacy, indicating that the sulfonamide structure contributes even more to the inhibition efficacy than the 1H-1,2,4-triazole ring. Among these compounds, compound 9n demonstrated comparable in vitro antiangiogenic activities to pazopanib in both HUVEC tube formation assay and the rat thoracic aorta rings (TARs) test. Meanwhile, compound 9n was identified to inhibit Akt1 (IC50=1.73 µM) and Abl tyrosine kinase (IC50=1.53 µM) effectively.

Developments of polo-like kinase 1 (Plk1) inhibitors as anti-cancer agents.

Polo-like kinases (Plks) are a family of serine/threonine kinases with a highly conserved N-terminal Ser/Thr kinase catalytic domain and a C-terminal region that play crucial roles in cell cycle progression. Plk1, playing a key role in multiple steps of mitotic progression, is the most studied member of the family. It is overexpressed in a wide spectrum of cancer types and is a promising target in oncology. Most of Plk1 inhibitors competitively bind to the ATP-binding site, which is characterized with unique features. Other inhibitors target regions outside the ATP pocket. In this review some pre-clinical or clinical Plk1 inhibitors are reported, focusing on SAR studies and biological activities, including the kinase activity, in vitro and in vivo anti-tumor efficacy. Those studies exhibited the inhibitors' significant therapeutic effects. Moreover, combination therapies of these Plk1 inhibitors with other anticancer drugs resulted with synergistic effects.

Discovery of a synthetic Aminopeptidase N inhibitor LB-4b as a potential anticancer agent.

APN inhibitors have been considered as potential anticancer agents for years. LB-4b is the first synthetic APN inhibitor to be evaluated for both of its anti-invasion and anti-angiogenesis effects. As a potent synthetic APN inhibitor (IC50=850 nM, versus bestatin of 8.1 µM), LB-4b was determined to have more significant block effects to cancer cell invasion and angiogenesis than bestatin. Besides, it is able to be easily synthesized with a high total yield, while the reported synthetic methods of bestatin are much more complex.

A novel aminopeptidase N inhibitor developed by virtual screening approach.

A virtual screening was performed to discover novel lead structures as potent aminopeptidase N(APN) inhibitors. A commercial database containing about 1,60,000 molecules in SPECS was filtered by rule of five, zinc binding groups, pharmacophore models and binding pattern analysis. At last, 24 molecules were selected for enzyme inhibition assay and compound 2 exhibited the inhibition constant (K(i)) of 2.79±0.32 µM against APN compared with Bestatin (K(i)= 3.37±0.24 µM). Our results indicated that compound 2 exhibited good antiproliferative activities against a broad spectrum of human cancer cell lines, and induced cell cycle arrest at G1 phase and eventual apoptosis. Moreover, compound 2 can inhibit the invasion of MDA-MB-231 cells. In summary, our results suggest that compound 2, a potent APN inhibitor, is worthy of further development.

Discovery of novel vascular endothelial growth factor receptor 2 inhibitors: a virtual screening approach.

A virtual screening approach was performed to develop novel and potent vascular endothelial growth factor receptor 2 inhibitors. The Specs database was filtered by 'rule of five', a pharmacophore model, and docking filter. Sixteen molecules were selected for tube formation assay, a naphthalenol group containing molecule, 12, showed good performance in the study. In the following aortic ring assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, 12 was discovered to efficiently inhibit angiogenesis and tumor cell growth. It is the first time to discover naphthalenol scaffold as potent vascular endothelial growth factor receptor 2 inhibitors. Thus, a molecular dynamic simulation process was applied to discover key features of 12 in binding to vascular endothelial growth factor receptor 2. Hydrophobic interactions were discovered to play significant role in the ligand-receptor binding.

NGR-based strategies for targeting delivery of chemotherapeutics to tumor vasculature.

In the last decades, NGR-containing peptides have been proved useful for ligand-directed targeted delivery of various chemotherapeutic drugs to tumor vasculature. Aminopeptidase N (APN; CD13) has been demonstrated to be a key binding site for NGR peptides on tumor vasculature. For drug targeting, chemical means have been applied to couple NGR-peptides to small molecule drugs, such as cytokines, antiangiogenic compounds, viral particles, contrast agents, DNA complexes and other biologic response modifiers. Some products have shown impressive results in preclinical animal models, such as NGR-TNF which was currently tested in Phase III trials. In this article we will review the process of NGR-to-isoDGR transition and provide suggestions for the design of the diverse NGR peptide-chemotherapeutics conjugates.

The effect of different species aminopeptidase N structure on the activity screening of aminopeptidase N inhibitor.

Aminopeptidase N (APN) is a transmembrane metallopeptidase, which participates in the tumor progress such as proliferation, attachment, angiogenesis and tumor invasion. All of this makes APN as a good chemical therapeutic anti-tumor target. In the present study, we got a novel compound 16l which markedly inhibited the enzyme activity of porcine APN, and the inhibition constant, K(i), of 16l are similar to the positive medicine Bestatin determined using porcine APN. However, when tested using human tumor cells, 16l couldn't effectively inhibit the enzyme activity, cell viability, cell migration and invasion. Computer aided drug design verified that because of the difference in structure, the binding pattern of 16l in the active site of homo sapien and porcine APN was different. The compound 16l could effectively inhibit the enzyme activity of porcine APN, but not homo sapien APN located on the surface of tumor cells. Therefore, the activity screening of APN inhibitor using aminopeptidase N from porcine should be only preliminary determination. The real activity screening should be determined using homo sapien aminopeptidase N.

Design, synthesis, and QSAR studies of novel lysine derives as amino-peptidase N/CD13 inhibitors.

A series of novel l-lysine derivatives were designed, synthesized, and assayed for their inhibitory activities on amino-peptidase N (APN)/CD13 and matrix metalloproteinase-2 (MMP-2). The preliminary biological test showed that most of the compounds displayed a high inhibitory activity against MMP-2 and a low activity against APN except compound B6 which exhibited good potency (IC(50)=13.2microM) similar with APN inhibitor Bestatin (IC(50)=15.5microM), and could be used as lead compound in the future.

Design, synthesis and evaluation of novel sulfonyl pyrrolidine derivatives as matrix metalloproteinase inhibitors.

A series of novel sulfonyl pyrrolidine derivatives were designed, synthesized and assayed for their inhibitory activities on matrix metalloproteinase 2 (MMP-2) and aminopeptidase N (AP-N). The results showed that these pyrrolidine derivatives exhibited highly selective inhibition against MMP-2 as compared with AP-N. Compounds 6a-d were more potent MMP-2 inhibitors than the positive control LY52. The structure-activity relationships were also briefly discussed.

[Enhancing effect of Ulex europaeus agglutinin I modified liposomes on oral insulin absorption in mice].

AIM: To investigate the enhancing effect on insulin absorption through GI. tract in mice by using the Ulex europaeus agglutinin I (UEA1) modified liposomes as the carrier. METHODS: UEA1 modified phosphatidylethanolamine (PE) was prepared by conjugating method of 1-ethyl-3-(3'-dimethylaminopropyl) carbodiimide (EDC), then the modified compound (PE-UEA1) was incorporated into the conventional liposomes of insulin to obtain UEA1 modified liposomes. The agglutination test was performed to examine the UEA1 biological activities after synthesis and modification. When liposomes were applied to healthy mice or diabetic mice at insulin dose of 350 u x kg(-1) orally, the hypoglycemic effect was investigated according to the blood glucose level determination. RESULTS: The blood glucose levels of the healthy mice reduced by UEA1 modified liposomes were (84 +/- 15)% at 4 h, (78 +/- 11)% at 8 h and (90 +/- 12)% at 12 h after oral administration. The conventional liposomes and saline showed no effect. The blood glucose levels of the diabetic mice reduced by UEA1 modified liposomes were (73 +/- 7)% at 4 h, (74 +/- 9)% at 8 h, (86 +/- 9)% at 12 h after oral administration. CONCLUSION: The UEA1 modified liposomes promote the oral absorption of insulin due to the specific-site combination on M cell membrane.