Isobavachin

Isobavachin is an orally active, blood-brain barrier-penetrating prenylated flavonoid present in Psoralea corylifolia. Isobavachin inhibits human CYP2B6, CYP2C9, CYP2C19, UGT1A1, UGT1A9, and UGT2B7. Isobavachin suppresses MAPK activation, NF-κB nuclear translocation, overexpression of iNOS/COX-2, FcεRI-mediated signaling pathways, and RANKL-induced osteoclastogenesis. Isobavachin induces autophagy, cytotoxicity, neuronal differentiation, and NRF2 activation; it alleviates oxidative damage, inflammatory responses, apoptosis, iron accumulation, mitochondrial biogenesis, and mast cell degranulation. Isobavachin is applicable to research related to liver injury, inflammatory diseases, osteoporosis, liver cancer, prostate cancer, glioma, periodontitis-induced bone loss, and Alzheimer's disease^{[1][2][3][4][5][6][7][8][9]}. In Vitro:Isobavachin (100 nmol/L; from EB stage day 4 to day 8+10) promotes the differentiation of mouse embryonic stem (D3 line) cells into neurons and astrocytes via a mechanism involving protein prenylation, ERK phosphorylation activation, and down-regulation of p38 and JNK phosphorylation^[1].
Isobavachin (5-80 μM; 24 h) exerts dose-dependent cytotoxicity in AML12, HepG2, LO2, rat primary hepatocytes, and mouse primary hepatocytes with IC₅₀ values of 35.20 μM, 19.96 μM, 20.74 μM, 55.84 μM, and 56.84 μM, respectively, and autophagy inhibition attenuates this cytotoxicity^[2].
Isobavachin (5-80 μM; 24 h) induces dose-dependent LDH leakage in AML12, HepG2, LO2, rat primary hepatocytes, and mouse primary hepatocytes^[2].
Isobavachin (20-44 μM; 24 h) dose-dependently elevated autophagosomes, autolysosomes and autophagic vacuoles, enhanced autophagic flux, caused progressive mitochondrial damage and reduced intracellular ATP levels in AML12 cells. All these pro-autophagic effects verified by MDC fluorescence were attenuated by the AMPK inhibitor BAY-3827 (HY-112083)^[2].
Isobavachin (20-44 μM; 24 h) upregulates autophagy in AML12 cells via activating the AMPK-ULK1 pathway and inhibiting the PI3K-Akt-mTOR pathway, as shown by altered autophagy-related and signaling protein expression, and these effects are reversed by autophagy or AMPK inhibition^[2].
Isobavachin (ISO) binds with high affinity to purified PI3K and AKT proteins, with binding energies of -8.6 kcal/mol and -6.4 kcal/mol, respectively^[3].
Isobavachin (IBC) (3.75-30 μM; 3 h pre-incubation, followed by 21 h LPS treatment) inhibits lipopolysaccharide-induced inflammatory responses in RAW264.7 murine macrophages via suppression of the MAPK and NF-κB signaling pathways^[4].
Isobavachin (60 min) was metabolized via mono-oxidation and glucuronidation by human and mouse liver/intestine microsomes as well as recombinant CYP1A2/CYP2C19 and UGT isoforms. Oxidation generated metabolites M1-M3 (CL_int: 5.53-93.97 μl/min per mg), while glucuronidation produced G1-G2 (CL_int: 10.73-202.62 μl/min per mg), indicating higher efficiency of glucuronidation^[5].
Isobavachin (1-100 μM; 60 min) potently inhibits recombinant human CYP2B6 (K_i = 1.93 μM), CYP2C9 (K_i = 0.22 μM), and CYP2C19 (K_i = 1.55 μM) with dose-dependent, isoform-specific inhibition modes^[5].
Isobavachin (1-100 μM; 60 min) potently inhibits recombinant human UGT1A1 (K_i = 3.05 μM), UGT1A9 (K_i = 0.44 μM), and UGT2B7 (K_i = 0.05 μM) with dose-dependent, isoform-specific inhibition modes^[5].
Isobavachin (10 μM; 60 min)'s mono-oxidation and glucuronidation in individual human liver microsomes are significantly correlated with the activity of CYP1A2, CYP2C19, UGT1A1, and UGT1A9^[5].
Isobavachin (Iso) (1-10 μM; 1 h pre-incubation, 5-15 min Ag stimulation) concentration-dependently inhibits IgE/Ag-stimulated degranulation, eicosanoid production, and intracellular Ca²⁺ elevation in bone marrow-derived mast cells^[6].
Isobavachin (1.3-5 μM) concentration-dependently suppresses IgE/Ag-induced inflammatory genes in mast cells, as well as LPS-triggered NO, related transcripts and NF-κB activation in RAW 264.7 and peritoneal macrophages^[6].
Isobavachin (10 μM; 1 h pre-incubation, 15 min Ag stimulation) inhibits IgE/Ag-stimulated activation of proximal tyrosine kinases (Fyn, Lyn, Syk, Lck) and their downstream signaling pathways, including NF-κB, in bone marrow-derived mast cells^[6].
Isobavachin (10 μM; 5 min-4 h incubation) increases SHP-1 phosphorylation in resting bone marrow-derived mast cells in a Fyn- and Lyn-dependent manner^[6].
Isobavachin (10 μM; 1 h pre-incubation, 5 min-4 h Ag stimulation post-48 h SHP-1 siRNA transfection) has inhibitory effects on IgE/Ag-stimulated bone marrow-derived mast cell activation and signaling that are dependent on SHP-1^[6].
Isobavachin (7.5-30 μM; days 1-3, days 3-5, days 5-7) inhibits RANKL-induced osteoclastogenesis in bone marrow-derived macrophages in a dose- and time-dependent manner, with an IC₅₀ of 15 μM, and acts primarily during the early to middle stages of differentiation^[7].
Isobavachin (15-30 μM; 96 h) downregulates the expression of key osteoclast marker genes and proteins in RANKL-stimulated bone marrow-derived macrophages^[7].
Isobavachin (15-30 μM; 5 days) inhibits RANKL-induced F-actin ring formation in bone marrow-derived macrophages in vitro in a dose-dependent manner^[7].
Isobavachin (15-30 μM; 7 days) inhibits osteoclast-mediated bone resorption and F-actin ring formation on bone slices in a dose-dependent manner^[7].
Isobavachin alters the transcriptome of RANKL-induced osteoclasts, with significant enrichment of genes related to iron ion homeostasis, ROS metabolism, and the MAPK signaling pathway^[7].
Isobavachin (15-30 μM; 48-96 h) reduces cellular iron accumulation in RANKL-induced osteoclasts (bone marrow-derived macrophages and RAW264.7 cells) by upregulating Fpn1 expression and downregulating Tfr1, Ftl1, and Fth1 expression to promote iron efflux^[7].
Isobavachin (30 μM; 5 days) suppresses RANKL-induced osteoclastogenesis in RAW264.7 cells by upregulating Fpn1 expression, as demonstrated by partial reversal of IBA's effects with Fpn1 knockdown and enhanced effects with Fpn1 overexpression^[7].
Isobavachin (30 μM; 0, 15, 30, 60 min) upregulates Fpn1 expression in RANKL-stimulated RAW264.7 cells by inhibiting the MAPK signaling pathway (P38, JNK, and ERK)^[7].
Isobavachin (30 μM; 96 h) inhibits mitochondrial biogenesis and function in RANKL-induced bone marrow-derived macrophages, as evidenced by reduced mitochondrial gene expression, mitochondrial mass, mitochondrial DNA copy number, membrane potential, ROS production, and ATP levels^[7].
Isobavachin binds potently and selectively to human recombinant ApoE4 (K_d = 0.54 μM) and human recombinant ApoE3 (K_d = 0.62 μM)^[8].
Isobavachin (IBA) (7.5–30 μM) dose- and time-dependently suppressed RANKL-induced osteoclastogenesis in BMMs (IC₅₀ = 15 μM), mainly acting at early-to-middle differentiation stages, and also inhibited osteoclast formation in RAW264.7 cells after 5-day treatment^[9].
Isobavachin (15-30 μM) suppressed mRNA and protein levels of osteoclast markers, downregulated iron uptake/storage genes and proteins while upregulating iron efflux FPN1 in RANKL-stimulated BMMs after 96 h incubation. It also lessened total and ferrous iron accumulation in BMMs and RAW264.7 cells. Additionally, it dose-dependently inhibited F-actin ring formation (5 days) and osteoclast-mediated bone resorption (7 days) in BMMs^[9].
Isobavachin (30 μM) suppressed RANKL-induced activation of p38, JNK and ERK MAPK pathways in RAW264.7 cells, thereby upregulating FPN1. Its inhibition of RANKL-triggered osteoclastogenesis was partially mediated by FPN1 upregulation and further strengthened by FPN1 overexpression^[9]. In Vivo:Isobavachin (ISO) (10 mg/kg; p.o.) confers significant hepatoprotection against Acetaminophen (HY-66005)-induced liver injury in mice by inhibiting CYP2E1-mediated acetaminophen bioactivation, activating the NRF2 antioxidant pathway, and activating the PI3K/AKT anti-apoptotic signaling cascade^[3].
Isobavachin (IBC) (1-10 μM; immersion; pre-treatment for 3 hours prior to LPS stimulation) potently suppresses LPS-induced inflammatory responses (NO, ROS, neutrophil levels) in zebrafish embryos without reducing survival at these doses^[4].
Isobavachin (40 mg/kg; p.o.; single dose) undergoes extensive in vivo metabolism in healthy male KM mice, producing two glucuronide and three mono-oxidated metabolites, with glucuronidation as the dominant metabolic pathway^[5].
Isobavachin (Iso) (10-20 mg/kg; p.o.; single dose; 1 h before Ag challenge) dose-dependently attenuates mast cell-mediated passive cutaneous anaphylaxis reactions in mice, with the 20 mg/kg dose showing potency comparable to 50 mg/kg fexofenadine (HY-B0801)^[6].
Isobavachin (30 mg/kg; i.p.; once daily; 10 days) alleviates ligature-induced periodontitis-associated alveolar bone loss in C57BL/6 mice by reducing osteoclastogenesis^[7].
Isobavachin (30 mg/kg; i.p.; daily; 10 days) significantly reduces alveolar bone loss by inhibiting osteoclastogenesis in a mouse model of ligature-induced periodontitis, with measurable improvements in bone morphometric parameters and reduced osteoclast activity markers^[9].