Haplopine

Haplopine is a substance with anti-inflammatory, antioxidant and photoactivated antibacterial activities. It also acts as an inhibitor of UGT1A7 and a photoactivated restriction endonuclease inhibitor. Haplopine inhibits the mRNA/protein expression of IL-6, TSLP, GM-CSF, G-CSF, IL-4, IL-13 and COX-2, while upregulating the mRNA/protein expression of SOD, CAT and HO-1. Haplopine inhibits the glucuronidation reaction catalyzed by UGT1A7 through competitive hydrophobic binding. Haplopine exerts photoactivated restriction endonuclease inhibitory effects by binding to DNA. Haplopine exhibits photoactivated activity against methicillin-resistant Staphylococcus aureus. Haplopine alleviates symptoms of atopic dermatitis. Haplopine can be used in research related to atopic dermatitis and methicillin-resistant Staphylococcus aureus infections^[1][2][3][4]. In Vitro:Haplopine (12.5-25 μM; 0.5 h pre-incubation, 24 h stimulation) concentration-dependently inhibits the mRNA and protein expression of pro-inflammatory mediators IL-6, TSLP, GM-CSF and G-CSF in HaCaT cells stimulated with TNF-α/IFN-γ^[1].
Haplopine (12.5-50 μM; 0.5 h pre-incubation, 24 h stimulation) inhibits the mRNA and protein expression of pro-inflammatory mediators IL-4, IL-13, and COX-2 in TNF-α/IFN-γ-stimulated Jurkat T cells^[1].
Haplopine (12.5-50 μM; 0.5 h pre-incubation, 24 h stimulation) concentration-dependently restores the mRNA and protein expressions of antioxidant defense enzymes SOD, CAT and HO-1 in H₂O₂-stimulated Jurkat T cells^[1].
Haplopine (0.5-100 μM; 30-120 min) competitively inhibits the 4-MU glucuronidation reaction catalyzed by recombinant human UGT1A7, with an IC₅₀ of 13.4 μM, a K_i of 7.2 μM, and a calculated in vivo inhibition threshold of 0.72 μM^[3].
Haplopine (100 μM; 30-120 min) inhibits the 4-MU glucuronidation reaction catalyzed by recombinant human UGT1A9 by 45% at a concentration of 100 μM^[3].
Haplopine (100 μM; 30-120 min) inhibits the 4-MU glucuronidation reaction catalyzed by recombinant human UGT1A3 by 17% at a concentration of 100 μM^[3].
Haplopine (100 μM; 30-120 min) inhibits 35% of the 4-MU glucuronidation reaction catalyzed by recombinant human UGT2B4 at a concentration of 100 μM^[3].
Haplopine (12.5 nM/spot; overnight at 37°C) exhibits photoactivated antibacterial activity against methicillin-resistant Staphylococcus aureus after UVA irradiation, with a minimum inhibitory dose of 12.5 nM/spot, whereas it shows no activity in the dark^[4].
Haplopine (100 nM/spot; overnight at 37°C) exhibits weak photoactivated antibacterial activity against Candida albicans, with a minimum inhibitory dose of 100 nM/spot under UVA irradiation, while it shows no activity in dark conditions^[4]. In Vivo:Haplopine (0.05-0.1%; topical administration; once daily; for 14 consecutive days) dose-dependently ameliorates DNCB-induced atopic dermatitis-like skin lesions in male Balb/c mice^[1].