2. Signaling Pathways
  3. Neuronal Signaling
  4. Monoamine Oxidase
  5. MAO-A Isoform

MAO-A

Monoamine Oxidase A

Monoamine oxidase A (MAO-A) is a mitochondrial flavin-dependent enzyme that catalyzes the oxidative deamination of monoamine neurotransmitters and thereby regulates neurotransmitter homeostasis in the nervous system and peripheral tissues[1]. Mechanistically, MAO-A metabolizes serotonin and norepinephrine and contributes to dopamine turnover, generating aldehydes, ammonia, and hydrogen peroxide as metabolic by-products that influence cellular redox status and downstream biological responses[1][2]. Through its control of monoamine catabolism, MAO-A participates in neuropsychiatric and neurodegenerative pathways and has therefore become an important molecular target in neuroscience and drug discovery research[2][3]. In disease-related experimental systems, altered MAO activity has been associated with oxidative stress and tissue dysfunction, while pharmacological inhibition of MAO can modify neurotransmitter metabolism and related physiological outcomes[2][4]. Compared with the closely related isoform MAO-B, MAO-A shows higher substrate preference for serotonin and norepinephrine, whereas MAO-B preferentially metabolizes phenylethylamine and contributes differently to monoamine turnover, making isoform selectivity a critical consideration in experimental design and therapeutic development[3][5]. For experimental applications, selective MAO-A inhibitors such as clorgyline and moclobemide are widely used to investigate monoamine signaling, neurotransmitter metabolism, and MAO-dependent biological mechanisms, while reversible and irreversible inhibitor classes provide complementary pharmacological tools for mechanistic studies[4][6].

MAO-A Related Products (117):

Cat. No. Product Name Effect Purity
  • HY-124591
    TC-2153
    		Inhibitor 98.19%
    TC-2153 is a selective inhibitor of striatal-enriched protein tyrosine phosphatase (STEP), with psychotropic activity and low acute toxicity. TC-2153 increases the expression of brain-derived neurotropic factor (BDNF) in the brain. And it decreases MAOA and 5-HT1A receptors mRNA level in midbrain. TC-2153 also inhibits 5-HT2A receptor-mediated signaling.
  • HY-N12485
    MAO-A inhibitor 1
    		Inhibitor 98.55%
    MAO-A inhibitor 1 (compound VIII) is a MAO-A inhibitor, with an IC50 of 100 μM.
  • HY-N4246
    Bacopaside I
    		Inhibitor 99.20%
    Bacopaside I is an orally active aquaporin AQP1 inhibitor and PKC modulator with neuroprotective and anticancer activities. Bacopaside I specifically blocks the water channel and cGMP-gated ion channel activities of AQP1 without affecting AQP4, thereby inhibiting the migration of colon cancer cells expressing AQP1. Bacopaside I activates the Akt pathway by interacting with PI3K, specifically inhibits MAO-A, effectively alleviates neuron necrosis and apoptosis induced by oxygen-glucose deprivation, reduces oxidative stress, and regulates the surface expression of neuroreceptors. When combined with Bacopaside II (HY-N6016), Bacopaside I significantly reduces the viability, proliferation and invasion ability of breast cancer cells, and binds to the pregnane X receptor (PXR). Bacopaside I is applicable to the research of colon cancer, breast cancer, vascular dementia, cerebral ischemia and other related diseases.
  • HY-B1558A
    Bifemelane hydrochloride
    		Inhibitor 99.86%
    Bifemelane hydrochloride (MCI-2016) is a potent, selective and competitive inhibitor of monoamine oxidase A (MAO-A), with a Ki of 4.20 μM. Bifemelane hydrochloride also inhibits MAO-B noncompetitively with a Ki of 46.0 μM. Bifemelane hydrochloride has a potent antidepressant activity and can be used for the research of cognitive and emotional disturbances related to cerebrovascular disease.
  • HY-14196
    Toloxatone
    		Inhibitor 98.11%
    Toloxatone (MD 69276) is a reversible, selective MAO-A inhibitor that can cross the blood-brain barrier. Toloxatone increases the levels of serotonin (5-HT) and norepinephrine in the brain. Toloxatone reduces the immobility time in the forced swimming test in mice, inhibits killing behavior in rats without causing sedation, and shows a correlation between its free plasma concentration and cerebrospinal fluid concentration. Toloxatone is widely used in research related to depression, depressive disorders and Parkinson's disease.
  • HY-101392A
    Harmane hydrochloride
    		Inhibitor 99.88%
    Harmane hydrochloride is a benzodiazepine receptor inhibitor (IC50=7 μM), with IC50 values for mACh, Opioid Receptor, MAO-A/B, and α2-adrenergic receptor of 24 μM, 2.8 μM, 0.5 μM, 5 μM, and 18 μM, respectively. Harmane hydrochloride inhibits the I1 imidazoline receptor (IC50 = 30 nM) to reduce blood pressure and has antidepressant, anti-anxiety, anticonvulsant, and analgesic effects. Harmane hydrochloride inhibits dopamine biosynthesis by decreasing tyrosine hydroxylase (TH) activity and enhancing L-DOPA-induced cytotoxicity in PC12 cells. Additionally, Harmane hydrochloride can increase the mutagenic effect induced by 2-acetylaminofluorene (AAF).
  • HY-W655727
    (-)-2-Phenylpropylamine
    		Inhibitor 98.44%
    (-)-2-Phenylpropylamine ((S)-2-Phenylpropylamine) (compound 3b) is a MAO-A and MAO-B inhibitor with Ki values of 584 μM and 156 μM, respectively.
  • HY-125515
    Tetrahydroharmine
    		Inhibitor 99.61%
    Tetrahydroharmine (Leptaflorine) is a selective reversible monoamine oxidase A (MAO-A) inhibitor with an IC50 of 74 nM. Tetrahydroharmine can be used for the research of parkinson’s disease.
  • HY-131036
    MAO-IN-M30 dihydrochloride
    		Inhibitor 98.56%
    MAO-IN-M30 dihydrochloride is an orally active, brain-permeable, and brain selective irreversible MAO-A (IC50=37 nM) and MAO-B (IC50=57 nM) inhibitor. MAO-IN-M30 dihydrochloride is a potent iron chelator and radical scavenger. MAO-IN-M30 dihydrochloride has a neuroprotective effect against Dexamethasone-induced brain cell apoptosis. MAO-IN-M30 dihydrochloride also exhibits neurorestorative activity in post MPTP and lactacystin models of Parkinson's disease. MAO-IN-M30 (dihydrochloride) is a click chemistry reagent, it contains an Alkyne group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups.
  • HY-101169
    Tetrindole mesylate
    		Inhibitor 99.93%
    Tetrindole mesylate is a selective inhibitor of monoamine oxidase A (MAO A). Tetrindole mesylate inhibits rat brain mitochondrial MAO A in a competitive manner with a Ki value of 0.4 μM and inhibits MAO B with a Ki of 110 μM. Tetrindole mesylate has antidepressant activity.
  • HY-106770
    Esuprone
    		Inhibitor 99.67%
    Esuprone is a brain-penetrant, orally active and selective MAO A inhibitor with an IC50 of 7.3 nM. Esuprone can be used for neurological research.
  • HY-W049881
    9-Methyl-β-carboline
    		Inhibitor 99.86%
    9-Methyl-β-carboline is a monoamine oxidase inhibitor and dopaminergic modulator, with an IC50 of 1 μM against human MAO-A and an IC50 of 15.5 μM against human MAO-B. 9-Methyl-β-carboline possesses cognitive enhancement potential and can cross the blood-brain barrier. 9-Methyl-β-carboline increases dopamine levels by inhibiting monoamine oxidase activity and microglial proliferation. 9-Methyl-β-carboline activates PKA/PKC and mitochondrial respiratory chain complex I, promotes neurotrophic factor expression and reduces α-synuclein (α-synuclein) levels, thereby reversing neurotoxin-induced dopaminergic neuron damage. 9-Methyl-β-carboline also regulates the PI3K pathway and exerts an anti-proliferative effect on astrocytes. 9-Methyl-β-carboline is widely used in Parkinson's disease-related studies.
  • HY-N7598
    Chrysophanol-1-O-β-gentiobioside
    		Inhibitor 99.0%
    Chrysophanol-1-O-β-gentiobioside, an anthraquinone glycoside isolated from Cassia obtusifolia seeds. Chrysophanol-1-O-β-gentiobioside shows selective inhibition of hMAO-A isozyme activity (IC50=96.15 μM).
  • HY-14895
    Fabomotizole
    		Inhibitor 99.96%
    Fabomotizole (CM346) is an insecticide with anxiolytic, antianxiety, and neuroprotective activities and a substrate of p-glycoprotein. Fabomotizole inhibits the ST-segment depression induced by isoproterenol in a rat model of acute subendocardial ischemia. Fabomotizole also inhibits Giardia lamblia and has the potential to inhibit giardiasis. Fabomotizole also targets Sigma1R, NRH:quinone reductase 2 (NQO2), and MAO-A to exert anxiolytic effects.
  • HY-120017
    Befloxatone
    		Inhibitor
    Befloxatone (MD-370503) is an orally active, selective and reversible inhibitor of Monoamine Oxidase A (MAO-A) (IC50=4 nM). Befloxatone increases the tissue level of monoamine, striatal dopamine and cortical norepinephrine. Befloxatone has antidepressant potential.
  • HY-151596
    MAO-A/5-HT2AR-IN-1
    		Inhibitor 99.71%
    MAO-A/5-HT2AR-IN-1 (compound I14) is a potent MAO-A and 5-HT2AR dual inhibitor, with IC50 values of 0.004 and 0.014 μM, respectively. MAO-A/5-HT2AR-IN-1 is a potential antidepressant agent.
  • HY-156255
    MAO-B-IN-25
    		Inhibitor 99.11%
    MAO-B-IN-25 (compound 92) is a selective MAO-B inhibitor with IC50s of 0.5 nM and 240 nM for MAO-A and MAO-B, respectively.
  • HY-121072
    ASS234
    		Inhibitor 99.6%
    ASS234 is a potent monoamino oxidase (MAO) inhibitor with IC50s of 5.2 nM and 43 nM for MAO-A and MAO-B, respectively. ASS234 also inhibits AChE and BuChE with IC50s of 350 nM and 460 nM, respectively.
  • HY-149234
    MAO-B-IN-18
    		Inhibitor 99.84%
    MAO-B-IN-18 is a potent and selective MAO B inhibitor with IC50s of 52 nM and 14 μM for hMAO B and hMAO A, respectively. MAO-B-IN-18 enables promising cytoprotective effects against hydrogen peroxide insults in neuroblastoma and astrocytes cultures.
  • HY-W721302
    2-APB hydrochloride
    		Inhibitor 99.9%
    2-APB is an analog of 6-APB, a benzofuran derivative and a psychoactive substance. Certain benzofuran derivatives have monoamine oxidase-A inhibitory activity .