A Near-Infrared Probe Tracks and Treats Lung Tumor Initiating Cells by Targeting HMOX2

Kim, Jong-Jin,Lee, Yong-An,Su, Dongdong,Lee, Jungyeol,Park, Sung-Jin,Kim, Beomsue,Jane Lee, Jia Hui,Liu, Xiao,Kim, Seong Soon,Bae, Myung Ae,Lee, Jun-Seok,Hong, Seong Cheol,Wang, Lu,Samanta, Animesh,Kw American Chemical Society 2019 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.141 No.37

<P>Tumor initiating cells (TIC) are resistant to conventional anticancer therapy and associated with metastasis and relapse in cancer. Although various TIC markers and their antibodies have been proposed, it is limited to the use of antibodies for in vivo imaging or treatment of TIC. In this study, we discovered heme oxygenase 2 (HMOX2) as a novel biomarker for TIC and developed a selective small molecule probe TiNIR (tumor initiating cell probe with near infrared). TiNIR detects and enriches the functionally active TIC in human lung tumors, and through the photoacoustic property, TiNIR also visualizes lung TIC in the patient-derived xenograft (PDX) model. Furthermore, we demonstrate that TiNIR inhibits tumor growth by blocking the function of HMOX2, resulting in significantly increased survival rates of the cancer model mice. The novel therapeutic target HMOX2 and its fluorescent ligand TiNIR will open a new path for the molecular level of lung TIC diagnosis and treatment.</P> [FIG OMISSION]</BR>

Myricetin Inhibits the Release of Glutamate in Rat Cerebrocortical Nerve Terminals

Yi Chang,Chia-Ying Chang,Su-Jane Wang,Shu-Kuei Huang 한국식품영양과학회 2015 Journal of medicinal food Vol.18 No.5

The excessive release of glutamate is a critical element in the neuropathology of acute and chronic brain disorders. The purpose of the present study was to investigate the effect and possible mechanism of myricetin, a naturally occurring flavonoid with a neuroprotective profile, on endogenous glutamate release in the nerve terminals (synaptosomes) of the rat cerebral cortex. The release of glutamate was evoked by the K+ channel blocker 4-aminopyridine (4-AP) and measured by one-line enzyme-coupled fluorometric assay. We also used a membrane potential-sensitive dye to assay the synaptosomal plasma membrane potential, and a Ca2 + indicator Fura-2 to monitor cytosolic Ca2 + concentrations ([Ca2 + ]C). Results show that myricetin inhibited 4-AP-evoked glutamate release, and this effect was prevented by chelating extracellular Ca2 + ions and the vesicular transporter inhibitor bafilomycin A1. However, the glutamate transporter inhibitor dl-threo-beta-benzyl-oxyaspartate had no effect on myricetin action. Myricetin did not alter the synaptosomal membrane potential, but decreased 4-APinduced increases in the cytosolic free Ca2 + concentration. Furthermore, the myricetin effect on 4-AP-evoked glutamate release was prevented by blocking the Cav2.2 (N-type) and Cav2.1 (P/Q-type) channels, but not by blocking intracellular Ca2 + release. These results suggest that myricetin inhibits glutamate release from cerebrocortical synaptosomes by attenuating voltage-dependent Ca2 + entry. This implies that the inhibition of glutamate release is an important pharmacological activity of myricetin that may play a critical role in the apparent clinical efficacy of this compound.

Echinacoside, an active constituent of Herba Cistanche, suppresses epileptiform activity in hippocampal CA3 pyramidal neurons

Lu, Cheng-Wei,Huang, Shu-Kuei,Lin, Tzu-Yu,Wang, Su-Jane The Korean Society of Pharmacology 2018 The Korean Journal of Physiology & Pharmacology Vol.22 No.3

Echinacoside, an active compound in the herb Herba Cistanche, has been reported to inhibit glutamate release. In this study, we investigated the effects of echinacoside on spontaneous excitatory synaptic transmission changes induced by 4-aminopyridine (4-AP), by using the in vitro rat hippocampal slice technique and whole-cell patch clamp recordings from CA3 pyramidal neurons. Perfusion with echinacoside significantly suppressed the 4-AP-induced epileptiform activity in a concentration-dependent manner. Echinacoside reduced 4-AP-induced increase in frequency of spontaneous excitatory postsynaptic currents (sEPSCs) but it did not affect the amplitude of sEPSCs or glutamate-activated currents, implicating a presynaptic mechanism of action. Echinacoside also potently blocked sustained repetitive firing, which is a basic mechanism of antiepileptic drugs. These results suggest that echinacoside exerts an antiepileptic effect on hippocampal CA3 pyramidal neurons by simultaneously decreasing glutamate release and blocking abnormal firing synchronization. Accordingly, our study provides experimental evidence that echinacoside may represent an effective pharmacological agent for treating epilepsy.

Albanin A, Derived from the Root Bark of Morus alba L., Depresses Glutamate Release in the Rat Cerebrocortical Nerve Terminals via Ca2+/Calmodulin/Adenylate Cyclase 1 Suppression

Yi Chang,Chi-Feng Hung,Horng Huey Ko,Su-Jane Wang 한국식품영양과학회 2021 Journal of medicinal food Vol.24 No.3

Decreasing synaptic release of glutamate may counteract glutamate excitotoxicity in many neurological diseases. In this study, we investigated the effect of albanin A, a constituent in the root bark of Morus alba L., on the release of glutamate in rat cerebral cortex nerve endings (synaptosomes). We found that albanin A at 5–30μM suppressed 4-aminopyridine (4-AP)-induced release of glutamate. This phenomenon was abolished by extracellular calcium removal or by vesicular transporter inhibition, and was associated with a decrease in intrasynaptosomal Ca2+ levels. However, albanin A had no effect on the synaptosomal membrane potential. The inhibition of N- and P/Q-type Ca2+ channels, calmodulin, adenylate cyclase (AC), and protein kinase A, abolished the effect of albanin A on the glutamate release evoked by 4-AP. Moreover, the albanin A-mediated inhibition of glutamate release was prevented by the Ca2+/calmodulin-stimulated AC1 inhibitor. Western blot showed that AC1, but not AC8, was presented in the synaptosomes, and albanin A reduced 4-AP-induced increases in synaptosomal cyclic adenosine monophosphate content. In addition, albanin A pretreatment substantially attenuated neuronal damage in a rat model of kainic acid-induced glutamate excitotoxicity. Our data reveal that albanin A suppresses glutamate release by decreasing Ca2+/calmodulin/AC1 activation in synaptosomes and exerts neuroprotective effect in vivo.

Ferulic Acid Suppresses Glutamate Release Through Inhibition of Voltage-Dependent Calcium Entry in Rat Cerebrocortical Nerve Terminals

Tzu Yu Lin,Cheng Wei Lu,Shu-Kuei Huang,Su-Jane Wang 한국식품영양과학회 2013 Journal of medicinal food Vol.16 No.2

This study investigated the effects and possible mechanism of ferulic acid, a naturally occurring phenolic compound, on endogenous glutamate release in the nerve terminals of the cerebral cortex in rats. Results show that ferulic acid inhibited the release of glutamate evoked by the K+ channel blocker 4-aminopyridine (4-AP). The effect of ferulic acid on the evoked glutamate release was prevented by chelating the extracellular Ca2+ ions, but was insensitive to the glutamate transporter inhibitor DL-threo-beta-benzyl-oxyaspartate. Ferulic acid suppressed the depolarization-induced increase in a cytosolic-free Ca2+ concentration, but did not alter 4-AP–mediated depolarization. Furthermore, the effect of ferulic acid on evoked glutamate release was abolished by blocking the Cav2.2 (N-type) and Cav2.1 (P/Q-type) channels, but not by blocking ryanodine receptors or mitochondrial Na+/Ca2+ exchange. These results show that ferulic acid inhibits glutamate release from cortical synaptosomes in rats through the suppression of presynaptic voltage-dependent Ca2+ entry.

Allicin Inhibits Glutamate Release from Rat Cerebral Cortex Nerve Terminals Through Suppressing Ca2+ Influx and Protein Kinase C Activity

Cheng Wei Lu,Chi-Feng Hung,Tzu Yu Lin,Ting Yang Hsieh,Su-Jane Wang 한국식품영양과학회 2019 Journal of medicinal food Vol.22 No.7

Evidence indicates that indirect inhibitory regulation of glutamatergic transmission, via reducing glutamate release, may induce neuroprotection. The present work was designed to examine whether allicin, a major component of garlic with neuroprotective effects, affected the release of glutamate evoked by 4-aminopyridine in rat cerebrocortical nerve terminals (synaptosomes). Allicin caused a potent inhibition on the release of glutamate evoked by 4-aminopyridine, and this inhibitory effect was abolished in the presence of Ca2+-free medium and vesicular transporter inhibitor. Allicin decreased the 4-aminopyridine-evoked elevation of intrasynaptosomal Ca2+ levels, but had no effect on the synaptosomal plasma membrane potential. The allicin-mediated inhibition of glutamate release was prevented by the N- and P/Q-type channel blocker and the protein kinase C (PKC) inhibitor, but was not affected by the intracellular Ca2+-release inhibitors, mitogen-activated protein kinase inhibitor, and protein kinase A inhibitor. Western blotting data also showed that allicin significantly reduced the phosphorylation of PKC. Together, these data indicate that in rat cerebrocortical nerve terminals, allicin depresses glutamate release and appears to decrease N- and P/Q-type Ca2+ channel and PKC activity.

Echinacoside, an active constituent of Herba Cistanche, suppresses epileptiform activity in hippocampal CA3 pyramidal neurons

Cheng Wei Lu,Shu-Kuei Huang,Tzu Yu Lin,Su-Jane Wang 대한약리학회 2018 The Korean Journal of Physiology & Pharmacology Vol.22 No.3

Echinacoside, an active compound in the herb Herba Cistanche, has been reported to inhibit glutamate release. In this study, we investigated the effects of echinacoside on spontaneous excitatory synaptic transmission changes induced by 4-aminopyridine (4-AP), by using the in vitro rat hippocampal slice technique and whole-cell patch clamp recordings from CA3 pyramidal neurons. Perfusion with echinacoside significantly suppressed the 4-AP-induced epileptiform activity in a concentration-dependent manner. Echinacoside reduced 4-AP-induced increase in frequency of spontaneous excitatory postsynaptic currents (sEPSCs) but it did not affect the amplitude of sEPSCs or glutamate-activated currents, implicating a presynaptic mechanism of action. Echinacoside also potently blocked sustained repetitive firing, which is a basic mechanism of antiepileptic drugs. These results suggest that echinacoside exerts an antiepileptic effect on hippocampal CA3 pyramidal neurons by simultaneously decreasing glutamate release and blocking abnormal firing synchronization. Accordingly, our study provides experimental evidence that echinacoside may represent an effective pharmacological agent for treating epilepsy.

Eupafolin Suppresses P/Q-Type Ca²⁺ Channels to Inhibit Ca²⁺/ Calmodulin-Dependent Protein Kinase II and Glutamate Release at Rat Cerebrocortical Nerve Terminals

( Anna Chang ),( Chi-Feng Hung ),( Pei-Wen Hsieh ),( Horng-Huey Ko ),( Su-Jane Wang ) 한국응용약물학회 2021 Biomolecules & Therapeutics(구 응용약물학회지) Vol.29 No.6

Eupafolin, a constituent of the aerial parts of Phyla nodiflora, has neuroprotective property. Because reducing the synaptic release of glutamate is crucial to achieving pharmacotherapeutic effects of neuroprotectants, we investigated the effect of eupafolin on glutamate release in rat cerebrocortical synaptosomes and explored the possible mechanism. We discovered that eupafolin depressed 4-aminopyridine (4-AP)-induced glutamate release, and this phenomenon was prevented in the absence of extracellular calcium. Eupafolin inhibition of glutamate release from synaptic vesicles was confirmed through measurement of the release of the fluorescent dye FM 1-43. Eupafolin decreased 4-AP-induced [Ca²⁺]_i elevation and had no effect on synaptosomal membrane potential. The inhibition of P/Q-type Ca²⁺ channels reduced the decrease in glutamate release that was caused by eupafolin, and docking data revealed that eupafolin interacted with P/Q-type Ca²⁺ channels. Additionally, the inhibition of calcium/calmodulindependent protein kinase II (CaMKII) prevented the effect of eupafolin on evoked glutamate release. Eupafolin also reduced the 4-AP-induced activation of CaMK II and the subsequent phosphorylation of synapsin I, which is the main presynaptic target of CaMKII. Therefore, eupafolin suppresses P/Q-type Ca²⁺ channels and thereby inhibits CaMKII/synapsin I pathways and the release of glutamate from rat cerebrocortical synaptosomes.