Publications by authors named "Shiu Hwa Yeh"

Traumatic brain injury (TBI) constitutes a significant burden on global healthcare systems, especially affecting younger populations, where it is a leading cause of disability and mortality. Current treatments for TBI mainly focus on preventing further brain damage and controlling symptoms. However, despite these approaches, several clinical needs remain unmet.

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The development of opioid analgesics with reduced adverse effects is an unmet need. In a previous study, we discovered a unique combination of BPRMU191 and morphinan antagonists that produced potent antinociception with reduced adverse effects after central administration (intrathecal or intracerebroventricular). BPRMU191/naltrexone exhibits notable and pharmacological properties.

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Morphinan antagonists, which block opioid effects at mu-opioid receptors, have been studied for their analgesic potential. Previous studies have suggested that these antagonists elicit analgesia with fewer adverse effects in the presence of the mutant mu-opioid receptor (MOR; S196A). However, introducing a mutant receptor for medical applications represents significant challenges.

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The compelling demand of a consummate analgesic medication without addiction is rising due to the clinical mistreatment. Additionally, the series of severe untoward effects usually deterred the utilization while coping with serious pain. As a possible turning point, we revealed that compound 14 is a dual agonist of mu opioid receptor (MOR) and nociceptin-orphanin FQ opioid peptide (NOP) receptor in this study.

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Currently, there is a significant unmet need for novel analgesics with fewer side effects. In this study, we carried out structural modification of a hit compound previously identified in an artificial-intelligence (AI) virtual screening and discovered the potent analgesic, benzo[b]thiophene-2-carboxamide analog (compound 25) with new structural scaffold. We investigated the signaling pathways of opioid receptors mediated by compound 25, and found this racemic compound activated mu-opioid receptor through the cyclic adenosine monophosphate (cAMP) and β-arrestin-2-mediated pathways with strong potency and efficacy, and accompanying nociceptin-orphanin FQ opioid peptide and delta-opioid receptors through the cAMP pathway with weak potencies.

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We identified, via high-throughput screening using a FLIPR® calcium assay, compound 1, which incorporated a dihydroquinolinyl-2-oxoethylsulfanyl-(1H,5H)-pyrimidinedione core and activated the μ-opioid receptor (MOR) in the presence of naloxone or naltrexone. A structure-activity relationship study of the analogs of 1 led to the design of compound 21, which activated MOR in the presence of naloxone with an EC of 3.3 ± 0.

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Machine learning is a well-known approach for virtual screening. Recently, deep learning, a machine learning algorithm in artificial neural networks, has been applied to the advancement of precision medicine and drug discovery. In this study, we performed comparative studies between deep neural networks (DNN) and other ligand-based virtual screening (LBVS) methods to demonstrate that DNN and random forest (RF) were superior in hit prediction efficiency.

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Background: Glioblastoma is associated with poor prognosis and high mortality. Although the use of first-line temozolomide can reduce tumor growth, therapy-induced stress drives stem cells out of quiescence, leading to chemoresistance and glioblastoma recurrence. The specificity protein 1 (Sp1) transcription factor is known to protect glioblastoma cells against temozolomide; however, how tumor cells hijack this factor to gain resistance to therapy is not known.

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Patients with glioblastoma are at high risk of local recurrences after initial treatment with standard therapy, and recurrent tumor cells appear to be resistant to first-line drug temozolomide. Thus, finding an effective second-line agent for treating primary and recurrent glioblastomas is critical. Betulinic acid (BA), a natural product of plant origin, can cross the blood-brain barrier.

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Morphine is a strong painkiller acting through mu-opioid receptor (MOR). Full-length 7-transmembrane (TM) variants of MOR share similar amino acid sequences of TM domains in rodents and humans; however, interspecies differences in N- and C-terminal amino acid sequences of MOR splice variants dramatically affect the downstream signaling. Thus, it is essential to develop a mouse model that expresses human MOR splice variants for opioid pharmacological studies.

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There is unmet need to design an analgesic with fewer side effects for severe pain management. Although traditional opioids are the most effective painkillers, they are accompanied by severe adverse responses, such as respiratory depression, constipation symptoms, tolerance, withdrawal, and addiction. We indicated BPR1M97 as a dual mu opioid receptor (MOP)/nociceptin-orphanin FQ peptide (NOP) receptor full agonist and investigated the pharmacology of BPR1M97 in multiple animal models.

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Morphine is a unique opioid analgesic that activates the mu-opioid receptor (MOR) without efficiently promoting its endocytosis that may underlie side effects. Our objective was to discover a novel enhancer of ligand-induced MOR endocytosis and determine its effects on analgesia, tolerance and dependence. We used high-throughput screening to identify convallatoxin as an enhancer of ligand-induced MOR endocytosis with high potency and efficacy.

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Morphine is widely used for the treatment of severe pain. This analgesic effect is mediated principally by the activation of μ-opioid receptors (MOR). However, prolonged activation of MOR also results in tolerance, dependence, addiction, constipation, nausea, sedation, and respiratory depression.

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The accumulation of reactive oxygen species (ROS) commonly occurs during normal aging and during some acute/chronic progressive disorders. In order to avoid oxidative damage, scavenging of these radicals is important. Previously, we identified zinc finger protein 179 (Znf179) as a neuroprotector that increases antioxidant enzymes against superoxide radicals.

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Background: The authors investigated the pharmacology and signaling pathways of the opioid receptors modulated by compound 1, 1-(2,4-dibromophenyl)-3,6,6-trimethyl-1,5,6,7-tetrahydro-4H-indazol-4-one.

Methods: In vitro studies of compound 1 were assessed by using a radioligand-binding assay (n = 3), a cyclic adenosine monophosphate assay (n = 3), a β-arrestin assay (n = 3), an internalization assay (n = 3), and an immunohistochemistry (n = 8). In vivo studies of compound 1 were characterized using a tail-flick test (n = 5 to 6), tail-clip test (n = 7), von Frey hair test (n = 5), and charcoal meal test (n = 5).

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Naloxone is an alkaloid antagonist that acts as an antidote to opioids through the mu-opioid receptor (MOR), a G protein-coupled receptor. However, its binding site on the MOR remains unknown. To investigate the binding interfaces necessary for naloxone and MOR, available structural information was combined with a cell-based photocrosslinking approach.

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After sudden traumatic brain injuries, secondary injuries may occur during the following days or weeks, which leads to the accumulation of reactive oxygen species (ROS). Since ROS exacerbate brain damage, it is important to protect neurons against their activity. Zinc finger protein 179 (Znf179) was shown to act as a neuroprotective factor, but the regulation of gene expression under oxidative stress remains unknown.

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Background: Glioma stem-like cells (GSCs) are proposed to be responsible for high resistance in glioblastoma multiforme (GBM) treatment. In order to find new strategies aimed at reducing GSC stemness and improving GBM patient survival, we investigated the effects and mechanism of a histone deacetylases (HDACs) inhibitor, suberoylanilide hydroxamic acid (SAHA), since HDAC activity has been linked to cancer stem-like cell (CSC) abundance and properties.

Methods: Human GBM cell lines were plated in serum-free suspension cultures allowed for sphere forming and CSC enrichment.

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μ-Opioid receptor (MOR) agonists are analgesics used clinically for the treatment of moderate to severe pain, but their use is associated with severe adverse effects such as respiratory depression, constipation, tolerance, dependence, and rewarding effects. In this study, we identified N-({2-[(4-bromo-2-trifluoromethoxyphenyl)sulfonyl]-1,2,3,4-tetrahydro-1-isoquinolinyl}methyl)cyclohexanecarboxamide (1) as a novel opioid receptor agonist by high-throughput screening. Structural modifications made to 1 to improve potency and blood-brain-barrier (BBB) penetration resulted in compounds 45 and 46.

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The accumulation of reactive oxygen species (ROS) have implicated the pathogenesis of several human diseases including neurodegenerative disorders, stroke, and traumatic brain injury, hence protecting neurons against ROS is very important. In this study, we focused on sigma-1 receptor (Sig-1R), a chaperone at endoplasmic reticulum, and investigated its protective functions. Using hydrogen peroxide (H2O2)-induced ROS accumulation model, we verified that apoptosis-signaling pathways were elicited by H2O2 treatment.

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A structure-based virtual screening strategy, comprising homology modeling, ligand-support binding site optimization, virtual screening, and structure clustering analysis, was developed and used to identify novel tryptophan 2,3-dioxygenase (TDO) inhibitors. Compound 1 (IC50 = 711 nM), selected by virtual screening, showed inhibitory activity toward TDO and was subjected to structural modifications and molecular docking studies. This resulted in the identification of a potent TDO selective inhibitor (11e, IC50 = 30 nM), making it a potential compound for further investigation as a cancer therapeutic and other TDO-related targeted therapy.

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Heterogeneous nuclear ribonucleoprotein K (hnRNP K) binds to the promoter region of mu-opioid receptor (MOR) to regulate its transcriptional activity. How hnRNP K contributes to the analgesic effects of morphine, however, is largely unknown. We provide evidence that morphine increases hnRNP K protein expression via MOR activation in rat primary cortical neurons and HEK-293 cells expressing MORs, without increasing mRNA levels.

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The μ-opioid receptor (MOR) is the major opioid receptor targeted by most analgesics in clinical use. However, the use of all known MOR agonists is associated with severe adverse effects. We reported that the 1-phenyl-3,6,6-trimethyl-1,5,6,7-tetrahydro-4H-indazol-4-ones are novel opioid receptor agonists.

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The nucleolar 58-kDa microspherule protein (MSP58) protein is a candidate oncogene implicated in modulating cellular proliferation and malignant transformation. In this study, we show that knocking down MSP58 expression caused aneuploidy and led to apoptosis, whereas ectopic expression of MSP58 regulated cell proliferation in a context-dependent manner. Specifically, ectopic expression of MSP58 in normal human IMR90 and Hs68 diploid fibroblasts, the H184B5F5/M10 mammary epithelial cell line, HT1080 fibrosarcoma cells, primary mouse embryonic fibroblasts, and immortalized NIH3T3 fibroblasts resulted in induction of premature senescence, an enlarged and flattened cellular morphology, and increased senescence-associated β-galactosidase activity.

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The exact mechanism underlying increases in Sp1 and the physiological consequences thereafter remains unknown. In rat primary cortical neurons, oxygen-glucose deprivation (OGD) causes an increase in H(2)O(2) as well as Sp1 in early ischaemia but apparently does not change mRNA level or Sp1 stability. We hereby identified a longer 5'-UTR in Sp1 mRNA that contains an internal ribosome entry site (IRES) that regulates rapid and efficient translation of existing mRNAs.

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