Morin, a Bioflavonoid Suppresses Monosodium Urate Crystal-Induced Inflammatory Immune Response in RAW 264.7 Macrophages through the Inhibition of Inflammatory Mediators, Intracellular ROS Levels and NF-κB Activation.

Dhanasekar C ，Kalaiselvan S ，Rasool M 《PLoS One》

Morin, a dietary bioflavonol suppresses monosodium urate crystal-induced inflammation in an animal model of acute gouty arthritis with reference to NLRP3 inflammasome, hypo-xanthine phospho-ribosyl transferase, and inflammatory mediators.

The anti-inflammatory effect of morin, a dietary bioflavanol was explored on monosodium urate (MSU) crystal-induced inflammation in rats, an experimental model for acute gouty arthritis. Morin treatment (30mg/kg b.wt) significantly attenuated the ankle swelling and the levels of lipid peroxidation, nitric oxide, serum pro-inflammatory cytokines (tumor necrosis factor (TNF) -α, interleukin (IL)-1β, and IL-6), monocyte chemoattractant protein (MCP)-1, vascular endothelial growth factor (VEGF), prostaglandin E2 (PGE2), and articular elastase along with an increased anti-oxidant status (catalase (CAT) and superoxide dismutase (SOD)) in the joint homogenate of MSU crystal-induced rats. Histological assessment revealed that morin limited the diffusion of joint space, synovial hyperplasia, and inflammatory cell infiltrations. The mRNA expression of NLRP3 (nucleotide oligomerization domain (NOD)-like receptor family, pyrin domain containing 3) inflammasome, caspase-1, pro-inflammatory cytokines, MCP-1, inflammatory enzymes (inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2)), and nuclear factor-kappa B (NF-κB) p65 was found downregulated and HPRT (hypo-xanthine phospho-ribosyl transferase) mRNA expression was upregulated in morin treated MSU crystal-induced rats. In addition, morin treatment reduced the protein expression of NF-κB p65, p-NF-κB p65, iNOS, COX-2, and TNF-α. The results clearly demonstrated that morin exert a potent anti-inflammatory effect on MSU crystal-induced inflammation in rats.

Dhanasekar C ，Rasool M 《-》

Targeting inflammatory mediators with ferulic acid, a dietary polyphenol, for the suppression of monosodium urate crystal-induced inflammation in rats.

The aim of this study was to investigate the anti-inflammatory effect of ferulic acid, a dietary phenol, on monosodium urate (MSU) crystal-induced inflammation in rats, an experimental model for acute gouty arthritis. For the purpose of comparison, colchicine was used as a reference drug. Paw edema, levels/activities of elastase, lysosomal enzymes (acid phosphatase and β-galactosidase), nitric oxide, lipid peroxidation, antioxidant status and pro-inflammatory cytokines (tumor necrosis factor alpha (TNF-α) and interleukin (IL)-1β), and histology of ankle joints were evaluated in rats with MSU crystal-induced inflammation. The messenger RNA (mRNA) expression of pro-inflammatory cytokines (TNF-α and IL-1β), NLRP3 (nucleotide oligomerization domain (NOD)-like receptor family, pyrin domain containing 3) inflammasomes, caspase-1, and the transcription factor nuclear factor kappa B p65 (NF-κB p65) was determined by real-time polymerase chain reaction (PCR) analysis. The protein expression of NF-κB p65 and TNF-α was detected by immunohistochemical analysis. Further, a molecular docking analysis was conducted to determine the ligand efficiency of ferulic acid towards NF-κB, apoptosis-associated speck-like protein containing a CARD (PYCARD/ASC), NLRP3, and pro-caspase-1. In the joint homogenate of rats with MSU crystal-induced inflammation, treatment with ferulic acid (30mg/kg body weight (b.wt)) decreased paw edema; the level/activity of elastase, lysosomal enzymes, nitric oxide, lipid peroxidation, and pro-inflammatory cytokines (TNF-α and IL-1β); and the mRNA expression of NLRP3 inflammasomes, caspase-1, pro-inflammatory cytokines, and NF-κB p65. In addition, the protein expression of NF-κB p65 and TNF-α was also found to be significantly decreased. However, the antioxidant status (superoxide dismutase (SOD) and catalase (CAT)) were found to be increased. The molecular docking analysis showed that ferulic acid exhibited significant ligand efficiency towards pro-caspase-1, NF-κB, PYCARD/ASC, and NLRP3. Our findings demonstrate the potential anti-inflammatory effect of ferulic acid on MSU crystal-induced inflammation in rats.

Doss HM ，Dey C ，Sudandiradoss C ，Rasool MK ... -  《-》

Triphala herbal extract suppresses inflammatory responses in LPS-stimulated RAW 264.7 macrophages and adjuvant-induced arthritic rats via inhibition of NF-κB pathway.

Kalaiselvan S ，Rasool MK 《-》

Berberine, an isoquinoline alkaloid suppresses TXNIP mediated NLRP3 inflammasome activation in MSU crystal stimulated RAW 264.7 macrophages through the upregulation of Nrf2 transcription factor and alleviates MSU crystal induced inflammation in rats.

The current study was designed to investigate the therapeutic potential of berberine on monosodium urate (MSU) crystal stimulated RAW 264.7 macrophages and in MSU crystal induced rats. Our results indicate that berberine (25, 50 and 75μM) suppressed the levels of pro-inflammatory cytokines (interleukin-1beta (IL-1β) and tumor necrosis factor alpha (TNFα)) and intracellular reactive oxygen species in MSU crystal stimulated RAW 264.7 macrophages. The mRNA expression levels of IL-1β, caspase 1, nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3 (NLRP3), thioredoxin interacting protein (TXNIP) and kelch-like ECH-associated protein 1 (Keap1) were found downregulated with the upregulation of nuclear factor erythroid-2-related factor 2 (Nrf2) transcription factor and its associated anti-oxidant enzymes: Heme oxygenase I (HO-1), superoxide dismutase (SOD1), glutathione peroxidase (GPx), NADPH quinone oxidoreductase-1 (NQO1) and catalase (CAT) in MSU crystal stimulated RAW 264.7 macrophages upon berberine treatment. Subsequently, western blot analysis revealed that berberine decreased the protein expression of IL-1β and caspase 1 and increased Nrf2 expression in RAW 264.7 macrophages. Immunofluorescence analysis also explored increased expression of Nrf2 in MSU crystal stimulated RAW 264.7 macrophages by berberine treatment. In addition, the paw edema, pain score, pro-inflammatory cytokines (IL-1β and TNFα) and articular elastase activity were found significantly reduced in berberine (50mg/kgb·wt) administered MSU crystal-induced rats. Conclusively, our current findings suggest that berberine may represent as a potential candidate for the treatment of gouty arthritis by suppressing inflammatory mediators and activating Nrf2 anti-oxidant pathway.

Dinesh P ，Rasool M 《-》