Search

Background Vascular abnormalities in the ovary cause infertility accompanied by ovarian insufficiency due to a microenvironment of barren ovarian tissues. Placenta-derived mesenchymal stem cells (PD-MSCs, Naïve) treatment in ovarian dysfunction shows angiogenic effect, however, the therapeutic mechanism between ovarian function and vascular remodeling still unclear. Therefore, we examined whether by phosphatase regenerating liver-1 (PRL-1), which is correlated with angiogenesis in reproductive systems, overexpressed PD-MSCs could maximize the angiogenic effects in an ovarian tissues injured of rat model with partial ovariectomy and their therapeutic mechanism by enhanced vascular function via PDGF signaling. Methods PD-MSCsPRL-1 (PRL-1) were generated by nonviral AMAXA gene delivery system and analyzed the vascular remodeling and follicular development in ovary. One week after Sprague–Dawley (SD) rats ovariectomy, Naïve and PRL-1 was transplanted. The animals were sacrificed at 1, 3 and 5 weeks after transplantation and vascular remodeling and follicular development were analyzed. Also, human umbilical vein endothelial cells (HUVECs) and ovarian explantation culture were performed to prove the specific effects and mechanism of PRL-1. Results Vascular structures in ovarian tissues (e.g., number of vessels, thickness and lumen area) showed changes in the Naïve and PRL-1-overexpressed PD-MSC (PRL-1) transplantation (Tx) groups compared to the nontransplantation (NTx) group. Especially, PRL-1 induce to increase the expression of platelet-derived growth factor (PDGF), which plays a role in vascular remodeling as well as follicular development, compared to the NTx. Also, the expression of genes related to pericyte and vascular permeability in arteries was significantly enhanced in the PRL-1 compared to the NTx (p Conclusions Our results show that PRL-1 restored ovarian function by enhanced vascular function via PDGF signaling pathway. These findings offer new insight into the effects of functionally enhanced stem cell therapy for reproductive systems and should provide new avenues to develop more efficient therapies in degenerative medicine.

Unintentional overdose deaths related to opioids and psychostimulants have increased in prevalence due to the adulteration of these drugs with fentanyl. Synergistic effects between illicit compounds and fentanyl cause aggravated respiratory depression, leading to inadvertent fatalities. Traditional small-molecule therapies implemented in the expanding opioid epidemic present numerous problems since they interact with the same opioid receptors in the brain as the abused drugs. In this study, we report an optimized dual hapten for use as an immunopharmacotherapeutic tool in order to develop antibodies capable of binding to fentanyl-contaminated heroin in the periphery, thus impeding the drugs’ psychoactive effects on the central nervous system. This vaccine produced antibodies with nanomolar affinities and effectively blocked opioid analgesic effects elicited by adulterated heroin. These findings provide further insight into the development of chemically contiguous haptens for broad-spectrum immunopharmacotherapies against opioid use disorders.

5-HT7 receptor (5-HT7R) agonists and antagonists have been reported to be used for treatment of neuropathic pain and depression, respectively. In this study, as a novel scaffold for 5-HT7R modulators, we designed and prepared a series of biphenyl-3-yl-methanamine derivatives with various amino groups. Evaluation of functional activities as well as binding affinities of the title compounds identified partial agonists (EC50 = 0.55–3.2 μM) and full antagonists (IC50 = 5.57–23.1 μM) depending on the amino substituents. Molecular docking study suggested that the ligand-based switch in functional activity from agonist to antagonist results from the size of the amino groups and thereby different binding modes to 5-HT7R. In particular, interaction of the ligand with Arg367 of 5-HT7R is shown to differentiate agonists and antagonists. In the pharmacophore model study, two distinct pharmacophore models can tell whether a ligand is an agonist or an antagonist. Taken together, this study provides valuable information for designing novel compounds with selective agonistic or antagonistic properties against 5-HT7R.

To cope with hypoxia, tumor cells have developed a number of adaptive mechanisms mediated by hypoxia-inducible factor 1 (HIF-1) to promote angiogenesis and cell survival. Due to significant roles of HIF-1 in the initiation, progression, metastasis, and resistance to treatment of most solid tumors, a considerable amount of effort has been made to identify HIF-1 inhibitors for treatment of cancer. Isolated from Saururus cernuus, manassantins A (1) and B (2) are potent inhibitors of HIF-1 activity. To define the structural requirements of manassantins for HIF-1 inhibition, we prepared and evaluated a series of manassantin analogues. Our SAR studies examined key regions of manassantin’s structure in order to understand the impact of these regions on biological activity and to define modifications that can lead to improved performance and drug-like properties. Our efforts identified several manassantin analogues with reduced structural complexity as potential lead compounds for further development. Analogues MA04, MA07, and MA11 down-regulated hypoxia-induced expression of the HIF-1α protein and reduced the levels of HIF-1 target genes, including cyclin-dependent kinase 6 (Cdk6) and vascular endothelial growth factor (VEGF). These findings provide an important framework to design potent and selective HIF-1α inhibitors, which is necessary to aid translation of manassantin-derived natural products to the clinic as novel therapeutics for cancers.

To develop novel, selective, and reversible MAO-B inhibitors for safer treatment of Parkinson’s disease, benzothiazole and benzoxazole derivatives with indole moiety were designed and synthesized. Most of the synthesized compounds showed inhibitory activities against MAO-B and selectivity over MAO-A. The most active compound was compound 5b, 6-fluoro-2-(1-methyl-1H-indol-5-yl)benzo[d]thiazole with an IC50 value of 28 nM with no apparent effect on MAO-A activity at 10 μM. Based on the reversibility assay, compound 5b turned out to be fully reversible with over 95% of recovery of enzyme activity after washout of the compound. Compound 5b showed a reasonable stability in human liver microsomes and did not affect the activities of CYP isozymes, suggesting an absence of high-risk drug–drug interaction. In an in vivo MPTP-induced animal model of Parkinson’s disease, oral administration of compound 5b showed neuroprotection of nigrostriatal dopaminergic neurons as revealed by tyrosine hydroxylase staining and pr...

© 2019 Elsevier Inc. Intrinsic and acquired drug resistance and induction of secondary malignancies limit successful chemotherapy. Because mutagenic translesion synthesis (TLS) contributes to chemoresistance as well as treatment-induced mutations, targeting TLS is an attractive avenue for improving chemotherapeutics. However, development of small molecules with high specificity and in vivo efficacy for mutagenic TLS has been challenging. Here, we report the discovery of a small-molecule inhibitor, JH-RE-06, that disrupts mutagenic TLS by preventing recruitment of mutagenic POL ζ. Remarkably, JH-RE-06 targets a nearly featureless surface of REV1 that interacts with the REV7 subunit of POL ζ. Binding of JH-RE-06 induces REV1 dimerization, which blocks the REV1-REV7 interaction and POL ζ recruitment. JH-RE-06 inhibits mutagenic TLS and enhances cisplatin-induced toxicity in cultured human and mouse cell lines. Co-administration of JH-RE-06 with cisplatin suppresses the growth of xenograft human melanomas in mice, establishing a framework for developing TLS inhibitors as a novel class of chemotherapy adjuvants. A small molecule specifically targeting the mutagenic branch of translesion synthesis binds a nearly featureless surface of REV1 to induce dimerization and block recruitment of POL ζ.

Structure–activity relationship (SAR) calculations were used to find monoamine oxidase-B (MAO-B) inhibitors by identifying pharmacophores exhibiting high inhibitory activities. Several such chromenylchalcones were designed and synthesized accordingly. Their inhibitory effects on MAO-B were determined using an HPLC-based method and an MAO-B enzyme assay kit. (E)-3-(6-Methoxy-2H-chromen-3-yl)-1-(2-methoxyphenyl)prop-2-en-1-one exhibited a half-maximal inhibitory concentration of 320 nM. Its molecular-level binding mode with the three-dimensional structure of MAO-B was elucidated using an in silico docking study. The chromenylchalcone scaffold, which is derived from natural products including isoflavonoids and chalcones, had not been previously reported as an MAO-B inhibitor.

In this study, as a bioisosteric alternative scaffold of the antiviral aryl diketoacids (ADKs), we used 5-hydroxychromone on which two arylmethyloxy substituents were installed. The 5-hydroxychromones (5b–5g) thus prepared showed anti-HCV activity and, depending on the aromatic substituents on the 2-arylmethyloxy moiety, some of the derivatives (5b–5f) were also active against SCV. In addition, unlike the ADKs which showed selective inhibition against the helicase activity of the SCV NTPase/helicase, the 5-hydroxychromones (5b–5f) were active against both NTPase and helicase activities of the target enzyme. Among those, 3-iodobenzyloxy-substituted derivative 5e showed the most potent activity against HCV (EC50 = 4 μM) as well as SCV (IC50 = 4 μM for ATPase activity, 11 μM for helicase activity) and this might be used as a platform structure for future development of the multi-target or broad-spectrum antivirals., Graphical abstract The 2,6-bis-arylmethyloxy-5-hydroxychromones were identified to have antiviral activity against both hepatitis C virus (HCV) and SARS-associated coronavirus (SCV). Highlights ► Investigation of bioisosteric alternative scaffold of antiviral arylmethyloxy-ADKs. ► 2,6-Bis-arylmethyloxy-5-hydroxychromones active against both HCV and SCV. ► Antiviral activity against HCV (EC50 = 4 μM). ► Inhibition of SCV NTPase (IC50 = 4 μM) as well as ATPase activity (IC50 = 11 μM). ► Potential platform structure for multi-target or broad-spectrum antivirals.

In order to increase stability of quercetin, its metabolically and chemically susceptible hydroxyl groups 7-OH and 3-OH respectively were transiently blocked with a pivaloxymethyl (POM) promoiety to provide two novel quercetin conjugates [7-O-POM-Q (2), 3-O-POM-Q (3)]. In the absence of stabilizer (ascorbic acid), the synthesized conjugates showed significantly increased stability in cell culture media [t1/2 = 4 h (2), 52 h (3)] compared with quercetin (t1/2 < 30 min) and quercetin prodrug 1 (t1/2 = 0.8 h). In addition, the quercetin conjugate 2 underwent efficient cellular uptake and intracellular levels of its hydrolysis product, quercetin, were maintained up to 12 h. Stability and intracellular accumulation of 2 were demonstrated by its stabilizer-independent cytostatic effect and induction of apoptotic cell death. Even though 3 was more stable than 2, it failed to penetrate cell membranes. However, the remarkable stability of 3 warrants further investigation of quercetin conjugates with various promoi...

In Parkinson's disease, the motor impairments are mainly caused by the death of dopaminergic neurons. Among the enzymes which are involved in the biosynthesis and catabolism of dopamine, monoamine oxidase B (MAO-B) has been a therapeutic target of Parkinson's disease. However, due to the undesirable adverse effects, development of alternative MAO-B inhibitors with greater optimal therapeutic potential towards Parkinson's disease is urgently required. In this study, we designed and synthesized the oxazolopyridine and thiazolopyridine derivatives, and biologically evaluated their inhibitory activities against MAO-B. Structure-activity relationship study revealed that the piperidino group was the best choice for the R(1) amino substituent to the oxazolopyridine core structure and the activities of the oxazolopyridines with various phenyl rings were between 267.1 and 889.5nM in IC50 values. Interestingly, by replacement of the core structure from oxazolopyrine to thiazolopyridine, the activities were significantly improved and the compound 1n with the thiazolopyridine core structure showed the most potent activity with the IC50 value of 26.5nM. Molecular docking study showed that van der Waals interaction in the human MAO-B active site could explain the enhanced inhibitory activities of thiazolopyridine derivatives.

Aryl diketoacid (ADK) is well known for antiviral activity which can be enhanced by introduction of an aromatic arylmethyl substituent. A natural flavonoid quercetin has a 3,5-dihydroxychromone pharmacophore which is in bioisosteric relationship with the 1,3-diketoacid moiety of the ADK. Thus, it was of our interest to test the antiviral activity of the quercetin derivatives with an arylmethyl group attached. In this study, we prepared a series of the 7-O-arylmethylquercetin derivatives with various aromatic substituents and evaluated their antiviral activity against the SARS-associated coronavirus (SARS-CoV, SCV) as well as hepatitis C virus (HCV). Single difference in the aromatic substituent fine-tuned the biological activity of the 7-O-arylmethylquercetin derivatives to result in two different classes of derivatives selectively active against SCV and HCV.

Background Abnormalities in nocturnal blood pressure dipping are well known for its relationship to cardiovascular diseases. Cerebral microbleeds are frequently observed in patients with hypertension and are known to be potent risk factors for stroke. However, there are scanty reports about the relationship between nocturnal dipping and cerebral microbleeds. Methods We recruited consecutive patients with both hypertension and ischemic stroke within 7 days after symptom onset, and those with cardioembolism were excluded. We applied 24-hour ambulatory blood pressure monitoring two weeks after stroke onset, and we used brain MRI to detect cerebral microbleeds. Various blood pressure parameters such as mean 24-hour blood pressure, awake/sleep blood pressure, and morning surge were compared between cerebral microbleeds (+) vs. (-) groups. Subjects were further classified according to nocturnal dipping status and were analyzed by logistic regression to determine its association with cerebral microbleeds with adjustment for age, gender, and cardiovascular risk factors. Results A total of 162 patients (100 males, age 65.33 ± 10.32 years) were included. Cerebral microbleeds were detected in 65 patients (40.1%). Most ambulatory blood pressure parameters except morning surge were significantly higher in those who had cerebral microbleeds. After adjusting for the confounding factors, the reverse dippers were prone to have cerebral microbleeds (odds ratio, 3.81; 95% confidential interval, 1.36-10.65; p-value = 0.01). Conclusion Cerebral microbleeds are independently associated with reverse dipping on ambulatory blood pressure monitoring in hypertensive stroke patients.