Jun Takayama

Dr. Jun Takayama

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Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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TATakashi Asano
Takashi Asano
XMXuan Meiyan Meiyan
Xuan Meiyan Meiyan
NINaohiro Iwata
Naohiro Iwata
JTJun Takayama
Jun Takayama
KHKousuke Hayashi
Kousuke Hayashi
MOMari Okazaki
Mari Okazaki
Tissue plasminogen activator, aiming to restore cerebral blood flow (CBF), has been used for acute ischemic strokes in clinics; however, its narrow therapeutic time window remains a serious concern. To develop novel prophylactic drugs to alleviate cerebral ischemia/reperfusion injuries, ferulic acid derivative 012 (FAD012) was synthesized and showed comparable antioxidant properties to ferulic acid (FA) and probably possesses the potent ability to cross the blood–brain barrier. A more potent cytoprotective effect of FAD012 against H2O2-induced cytotoxicity in PC12 cells was also observed. In vivo toxicity was not observed in rats given a long-term oral administration of FAD012, indicating its good tolerability. A one-week-course oral administration of FAD012 significantly alleviated middle cerebral artery occlusion (MCAO)-induced cerebral ischemia/reperfusion injuries in rats, accompanied by the restoration of CBF and endothelial nitrogen oxide synthetase (eNOS) expression. Treatment with FAD012 significantly restored the cell viability and eNOS expression damaged by H2O2, used to mimic MCAO-triggered oxidative stress, in rat brain microvascular endothelial cells. Our findings suggested that FAD012 protected the viability of vascular endothelium and maintained eNOS expression, ultimately contributing to the restoration of CBF, and may provide a rationale for the development of FAD012 into an effective prophylactic drug for patients at high risk of stroke.

1 September 2019 in Bioorganic & Medicinal Chemistry Letters
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AGArun K. Ghosh
Arun K. Ghosh
JWJacqueline N. Williams
Jacqueline N. Williams
SKSatish Kovela
Satish Kovela
JTJun Takayama
Jun Takayama
HSHannah M. Simpson
Hannah M. Simpson
HMHiroaki Mitsuya
Hiroaki Mitsuya

30 September 2025 in Biomedicines
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HSHiroshi Sugo
Hiroshi Sugo
HMHirokazu Matsuzaki
Hirokazu Matsuzaki
JTJun Takayama
Jun Takayama
NINaohiro Iwata
Naohiro Iwata
XMXuan Meiyan Meiyan
Xuan Meiyan Meiyan
MOMari Okazaki
Mari Okazaki
Background/Objectives: The rapid progression of stroke often results in irreversible brain damage and poor outcomes when treatment is delayed. Prophylactic administration of FAD012 (3,5-dimethyl-4-hydroxycinnamic acid), a synthetic derivative of ferulic acid (FA), has demonstrated cerebroprotective effects in ischemic models through antioxidant and endothelial protective mechanisms. This study investigated the effects of FAD012 on cerebral infarction and blood–brain barrier (BBB) integrity using a photothrombotic stroke model in rats. Methods: Male Sprague Dawley rats received a single intraperitoneal injection of FAD012 or FA (100 or 300 mg/kg) 60 min prior to stroke induction. Under isoflurane anesthesia, the middle cerebral artery was exposed, and stroke was induced by intravenous administration of Rose Bengal followed by green laser irradiation. Cerebral blood flow (CBF) was monitored by laser Doppler flowmetry. BBB disruption was evaluated by Evans Blue extravasation and immunohistochemistry for tight junction (TJ) proteins. Results: Control rats exhibited extensive infarction, BBB disruption, and reduced expression of claudin-5, occludin, and ZO-1, along with fragmented collagen IV. In contrast, FAD012 (300 mg/kg) significantly attenuated CBF reduction, reduced infarct size, preserved BBB integrity, and maintained TJ protein expression, with greater efficacy than an equivalent dose of FA. FAD012 also preserved the expression and phosphorylation of endothelial nitric oxide synthase (eNOS), a key marker of vascular integrity. The CBF-preserving effect of FAD012 was completely abolished by NG-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor. Conclusions: These findings suggest that FAD012 protects endothelial function, thereby contributing to the maintenance of CBF and BBB integrity, supporting its potential as a prophylactic therapeutic agent for ischemic stroke.

1 December 2025 in Appliedchem
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KSKoichi Shikama
Koichi Shikama
JTJun Takayama
Jun Takayama
XMXuan Meiyan Meiyan
Xuan Meiyan Meiyan
HMHirokazu Matsuzaki
Hirokazu Matsuzaki
BYBo Yuan
Bo Yuan
TSTakeshi Sakamoto
Takeshi Sakamoto
Ferulic acid (FA) is well known for its antioxidant properties and neuroprotective effects. To enhance these biological activities, we designed a novel series of FA derivatives by introducing a phenyl group at the α-position of the carboxyl moiety. Further structural modifications were achieved by incorporating hydroxy or alkoxy substituents at various positions on the two aromatic rings. A series of these derivatives were synthesized and evaluated for their antioxidant capacity using the DPPH radical scavenging assay, as well as their cytoprotective effects against oxidative stress in Neuro-2a cells. Among the synthesized compounds, one derivative exhibited significantly enhanced activity in both assays. Mechanistic studies indicated that this heightened efficacy is attributable to a unique reaction pathway involving dual antioxidant mechanisms.

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TATakashi Asano
Takashi Asano
HMHirokazu Matsuzaki
Hirokazu Matsuzaki
XMXuan Meiyan Meiyan
Xuan Meiyan Meiyan
BYBo Yuan
Bo Yuan
JTJun Takayama
Jun Takayama
MOMari Okazaki
Mari Okazaki
Dysphagia is a serious complication of stroke, yet effective pharmacological treatments remain limited. This study investigated the effects of FAD012 (3,5-dimethyl-4-hydroxy cinnamic acid), a synthetic derivative of ferulic acid (FA), on cerebral damage and swallowing dysfunction in a rat model of bilateral common carotid artery occlusion (2VO). Sprague–Dawley rats were orally administered FAD012 (3 or 10 mg/kg), FA (10 mg/kg), or 0.5% carboxymethyl cellulose (CMC, suspension vehicle) starting one week before 2VO. Two weeks after 2VO surgery, which was performed under isoflurane anesthesia, reflex swallowing was assessed by electromyographic recordings of the mylohyoid muscle under urethane anesthesia. Two weeks after 2VO, cerebral blood flow (CBF) declined to approximately 40% of baseline, and the number of reflex swallowing responses was significantly reduced in the CMC group. Additionally, 2VO induced O2− production, apoptotic cell death in the striatum, and a reduction in tyrosine hydroxylase expression. Substance P (SP) levels in the laryngopharyngeal mucosa, positively regulated by dopaminergic signaling in the basal ganglia, also decreased. FAD012 (10 mg/kg) effectively prevented the 2VO-induced reduction in CBF, enhanced the reflex swallowing, and preserved the dopamine-SP system. Notably, FAD012 exerted significantly stronger effects than FA at the same dose. These findings suggest that FAD012 maintains CBF under cerebral hypoperfusion and enhances the swallowing reflex by maintaining neuronal function in the striatal and laryngopharyngeal regions of 2VO rats.

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HMHirokazu Matsuzaki
Hirokazu Matsuzaki
Anna AraiAnna Arai
Anna Arai
XMXuan Meiyan Meiyan
Xuan Meiyan Meiyan
BYBo Yuan
Bo Yuan
JTJun Takayama
Jun Takayama
MOMari Okazaki
Mari Okazaki
Endothelial dysfunction is closely linked to inflammation and oxidative stress and ultimately contributes to the development of cardiovascular diseases. Lipopolysaccharide (LPS), a major component of Gram-negative bacteria, induces vascular inflammation and oxidative damage in experimental models. Curcumin (Cur), a polyphenol from Curcuma longa, is well known for its anti-inflammatory and antioxidant properties. In this study, we examined the protective effects of CUD003, a novel synthetic Cur derivative, on the LPS-induced impairment of endothelium-dependent relaxation in the thoracic aorta of mice. Male ICR mice were pretreated with CUD003 or Cur (3 or 10 mg/kg, p.o.) 30 min prior to LPS injection (10 mg/kg, i.p.). Twenty-four hours after LPS injection, vascular reactivity was assessed in isolated aortic rings by evaluating vasorelaxation and vasoconstriction responses. LPS markedly impaired acetylcholine-induced vasorelaxation in the phenylephrine (PE)-precontracted aortic rings, while PE-induced contraction and sodium nitroprusside-induced relaxation were preserved, indicating that LPS impaired endothelium-dependent relaxation without affecting smooth muscle function. Immunohistochemical analysis revealed a reduction in eNOS expression and elevated levels of TNF-α, COX-2, O2−, and malondialdehyde, indicating enhanced inflammation and oxidative stress in the aorta. Pretreatment with CUD003 (10 mg/kg) significantly ameliorated these changes and showed superior protective effects compared to the same dose of Cur. These findings suggest that CUD003 protects against LPS-induced vascular dysfunction and suppresses inflammation and oxidative stress, supporting its potential as a preventive candidate against vascular inflammation and dysfunction.