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Deepak, V.

Publications and source records attributed to Deepak, V..

4 recordsLinked to original sources

IKKβ as a putative non-covalent and quinone-mediated covalent target of 4-methylcatechol in RANKL/NF-κB signaling: a combined computational and experimental analysis

Excessive osteoclast activity contributes to pathological bone loss in osteoporosis, rheumatoid arthritis, and osteolytic malignancies. The effects of small catechol derivatives on receptor activator of nuclear factor-{kappa}B ligand (RANKL)-induced osteoclastogenesis remain poorly understood. This study investigated the effects of 4-methylcatechol (4-MC) on RANKL-induced NF-{kappa}B activation and osteoclast differentiation. 4-MC reduced RANKL-induced NF-{kappa}B luciferase activity in HEK-293T/RANK cells. 4-MC also suppressed RANKL-induced TRAP activity in RAW264.7 cells in a concentration-dependent manner and reduced the number of TRAP-positive multinucleated osteoclasts, without affecting cell viability. Molecular docking predicted non-covalent binding of 4-MC within the ATP-binding hinge region of IKK{beta} (PDB: 4KIK), forming a close polar contact with Glu97, predicted hydrogen bonds with Cys99, and a hydrophobic contact with Ile165, within the pocket occupied by the co-crystallized inhibitor K252a. Covalent docking predicted that the oxidized quinone form of 4-MC engages Cys179 in the IKK{beta} activation loop. Quantum chemical calculations confirmed a markedly higher electrophilicity index for the oxidized quinone than for the parent catechol, supporting this mechanism. In silico ADMET profiling indicated favorable drug-likeness and safety. These findings identify IKK{beta} as a plausible molecular target of 4-MC through both non-covalent and covalent mechanisms. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=108 SRC="FIGDIR/small/741661v1_ufig1.gif" ALT="Figure 1"> View larger version (40K): org.highwire.dtl.DTLVardef@1d9f82eorg.highwire.dtl.DTLVardef@134a24borg.highwire.dtl.DTLVardef@8aeb91org.highwire.dtl.DTLVardef@6fb85d_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

Asarinin Inhibits RANKL-Induced Osteoclast Differentiation by Targeting the p38/ERK-c-Fos-NFATc1 Axis

Excessive osteoclast formation is a key contributor to pathological bone loss in disorders such as osteoporosis and rheumatoid arthritis. Asarinin, a natural lignan, has not previously been examined in the context of osteoclast differentiation. Here, we investigated the anti-osteoclastogenic effects of asarinin using RANKL-stimulated RAW264.7 cells. Asarinin significantly suppressed TRAP-positive multinucleated osteoclast formation under the tested conditions. Mechanistically, asarinin selectively inhibited RANKL-induced phosphorylation of p38 and ERK MAPKs, leading to reduced c-Fos expression and inhibition of NFATc1 nuclear translocation. In addition, asarinin disrupted actin ring formation in mature osteoclasts. Collectively, these findings identify asarinin as a pathway-selective inhibitor of osteoclast differentiation, targeting the p38/ERK-c-Fos-NFATc1 axis while sparing parallel signaling pathways.

pharmacology and toxicology↗

Methyl Carnosate, a Carnosic Acid Derivative, Attenuates Osteoclastogenesis via Modulation of RANKL-Induced NF-κB Activity

Excessive osteoclast activity underlies bone-destructive diseases including osteoporosis and rheumatoid arthritis. RANKL-induced NF-{kappa}B signaling represents a critical pathway driving osteoclastogenesis. Here, we report that methyl carnosate, a naturally occurring diterpene from rosemary, inhibits RANKL-induced osteoclastogenesis with an IC50 of 1.2 M and displays greater potency than its parent compound, carnosic acid. Promoter-reporter analysis further indicates attenuation of RANKL-induced NF-{kappa}B activity. These findings identify methyl carnosate as a potential lead compound for the development of bone-protective therapeutics.

pharmacology and toxicology↗

8-Epixanthatin Suppresses RANKL-Induced Osteoclast Differentiation via Inhibition of NF-κB and MAPK Signaling

Osteoclast hyperactivity represents a central mechanism in pathological bone destruction, underscoring the importance of discovering novel anti-resorptive compounds. In this study, we present early-stage evidence that 8-Epixanthatin can inhibit osteoclast differentiation induced by RANKL. 8-Epixanthatin exhibited no significant cytotoxicity at the concentrations used for osteoclast differentiation studies. The compound showed concentration-dependent reductions in TRAP-positive multinucleated osteoclasts, with an IC50 value of 2.3 M. Our mechanistic investigations revealed that 8-Epixanthatin interferes with RANKL-activated signaling networks, particularly NF-{kappa}B and MAPK cascades. Collectively, these observations identify 8-Epixanthatin as a promising lead structure for anti-osteoclast drug discovery.

pharmacology and toxicology↗