(E)-2-methoxy-4-(3-(4-methoxyphenyl) prop-1-en-1-yl) Phenol Ameliorates MPTP-Induced Dopaminergic Neurodegeneration by Inhibiting the STAT3 Pathway

Abstract

Neuroinflammation is implicated in dopaminergic neurodegeneration. We have previously demonstrated that (E)-2-methoxy-4-(3-(4-methoxyphenyl) prop-1-en-1-yl) phenol (MMPP), a selective signal transducer and activator of transcription 3 (STAT3) inhibitor, has anti-inflammatory properties in several inflammatory disease models. We investigated whether MMPP could protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced dopaminergic cell loss and behavioral impairment. Imprinting control region (ICR) mice (8 weeks old, n = 10 per group) were administered MMPP (5 mg/kg) in drinking water for 1 month, and injected with MPTP (15 mg/kg, four times with 2 h intervals) during the last 7 days of treatment. MMPP decreased MPTP-induced behavioral impairments in rotarod, pole, and gait tests. We also showed that MMPP ameliorated dopamine depletion in the striatum and inflammatory marker elevation in primary cultured neurons by high-performance liquid chromatography and immunohistochemical analysis. Increased activation of STAT3, p38, and monoamine oxidase B (MAO-B) were observed in the substantia nigra and striatum after MPTP injection, effects that were attenuated by MMPP treatment. Furthermore, MMPP inhibited STAT3 activity and expression of neuroinflammatory proteins, including ionized calcium binding adaptor molecule 1 (Iba1), inducible nitric oxide synthase (iNOS), and glial fibrillary acidic protein (GFAP) in 1-methyl-4-phenylpyridinium (MPP+; 0.5 mM)-treated primary cultured cells. However, mitogen-activated protein kinase (MAPK) inhibitors augmented the activity of MMPP. Collectively, our results suggest that MMPP may be an anti-inflammatory agent that attenuates dopaminergic neurodegeneration and neuroinflammation through MAO-B and MAPK pathway-dependent inhibition of STAT3 activation.

Echinacoside Protects Dopaminergic Neurons Through Regulating IL-6/JAK2/STAT3 Pathway in Parkinson’s Disease Model

“…This signal pathway can also be triggered by exposure to manganese in microglia, leading to neuronal loss (Yin et al, 2018). However, microRNA-93 (Wang et al, 2021) and (E)-2methoxy-4-(3-(4-methoxyphenyl) prop-1-en-1-yl) phenol (Choi et al, 2019) can engender the downregulation of STAT3 to abrogate the MPTP-induced dopaminergic neurodegeneration. Similarly, nitidine has been shown to inhibit the phosphorylation of JAK2/STAT3 and block STAT3 nuclear translocation, exerting neuroprotective effects in PD models (Wang et al, 2016).…”

Neurobiology Research in Parkinson’s Disease

“…Recently, anti-inflammatory effects of (E)-2-methoxy-4-(3-(4-methoxyphenyl) prop-1-en-1-yl) phenol, a STAT3 inhibitor, was demonstrated. Oral intake of (E)-2-methoxy-4-(3-(4-methoxyphenyl) prop-1-en-1-yl) phenol for 1 month showed strong neuroprotective effects in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine mice model of PD [4]. The control of inflammation is a hopeful therapeutic target for PD.…”