• Biomolecules & Therapeutics
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• v.31 no.6
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• pp.599-610
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• 2023

According to recent evidence, ferroptosis is a major cell death mechanism in the pathogenesis of kidney injury and fibrosis. Despite the renoprotective effects of classical ferroptosis inhibitors, therapeutic approaches targeting kidney ferroptosis remain limited. In this study, we assessed the renoprotective effects of melatonin and zileuton as a novel therapeutic strategy against ferroptosis-mediated kidney injury and fibrosis. First, we identified RSL3-induced ferroptosis in renal tubular epithelial HK-2 and HKC-8 cells. Lipid peroxidation and cell death induced by RSL3 were synergistically mitigated by the combination of melatonin and zileuton. Combination treatment significantly downregulated the expression of ferroptosis-associated proteins, 4-HNE and HO-1, and upregulated the expression of GPX4. The expression levels of p-AKT and p-mTOR also increased, in addition to that of NRF2 in renal tubular epithelial cells. When melatonin (20 mg/kg) and zileuton (20 mg/kg) were administered to a unilateral ureteral obstruction (UUO) mouse model, the combination significantly reduced tubular injury and fibrosis by decreasing the expression of profibrotic markers, such as α-SMA and fibronectin. More importantly, the combination ameliorated the increase in 4-HNE levels and decreased GPX4 expression in UUO mice. Overall, the combination of melatonin and zileuton was found to effectively ameliorate ferroptosis-related kidney injury by upregulating the AKT/mTOR/ NRF2 signaling pathway, suggesting a promising therapeutic strategy for protection against ferroptosis-mediated kidney injury and fibrosis.

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.579-587
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• 2016

Mastitis is a prevalent inflammatory disease that remains one of the main causes of poor quality of milk. Phytoncides are naturally occurring anti-inflammatory compounds derived from plants and trees. To determine if treatment with phytoncide could decrease the severity of lipopolysaccharide (LPS)-induced inflammatory responses, mammary alveolar epithelial cells (MAC-T) were pretreated with phytoncide (0.02% and 0.04% (v/v)) followed by LPS treatment (1 and 25 μg/ml). The results demonstrated that phytoncide downregulated LPS-induced pro-inflammatory cyclooxygenase-2 (COX-2) expression. Additionally, LPS-induced activation of ERK1/2, p38, and Akt was attenuated by phytoncide. Treatment of cells with known pharmacological inhibitors of ERK1/2 (PD98059), p38 (SB203580), and Akt (LY294002) confirmed the association of these signaling pathways with the observed alterations in COX-2 expression. Moreover, phytoncide attenuated LPS-induced NF-κB activation and superoxide production, and, finally, treatment with phytoncide increased Nrf2 activation. Results suggest that phytoncide can decrease LPS-induced inflammation in MAC-T cells.

• The Journal of Internal Korean Medicine
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• v.42 no.1
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• pp.1-10
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• 2021

Objective: This study was conducted to investigate the effect of Chaenomelis Fructus (CF) water extract on thioacetamide (TAA)-treated rats. Methods: Rats were divided into five groups: one normal group (n=8) and four with TAA-induced hepatic injury. These treatment groups were administered distilled water (n=8); silymarin 100 mg/kg (n=8); CF 100 mg/kg (n=8); and CF 200 mg/kg (n=8). In the TAA groups, the acute liver injury was induced via IP injection (200 mg/kg), and the silymarin and CF extract were then orally administered for three days. Subsequently, serum levels of GOT, GPT, and ammonia were confirmed as well as protein expressions using liver tissue. Results: In the liver injury-induced rats, CF administration reduced tissue damage and serum levels of GOT, GPT, and ammonia. In addition, CF increased the anti-oxidant proteins Nrf2, Keap1, HO-1, and catalase and significantly regulated matrix metalloproteinases (MMP-2 and MMP-9) and their tissue inhibitors (TIMP-1 and TIMP-2). Conclusions: In this animal model of liver injury induced by TAA, CF extract is determined to have a hepatoprotective effect by increasing anti-oxidant proteins that relieve damage and by regulating the expression of matrix metalloproteinases.

• Journal of Life Science
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• v.29 no.4
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• pp.402-409
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• 2019

Korean red ginseng made from steaming and drying fresh ginseng has long been used as a traditional herbal medicine due to its effects on the immune, endocrine, and central nerve systems and its anti-inflammatory activity. In this study, we investigated the molecular mechanism responsible for the anti-inflammatory effects of a formulated Korean red ginseng extract (RGE) in response to lipoteichoic acid (LTA), a cell wall component of gram-positive bacteria. RGE inhibited LTA-induced nitric oxide (NO) secretion and inducible nitric oxide synthase (iNOS) expression in BV-2 microglial cells, without affecting cell viability. RGE also inhibited nuclear translocation of nuclear factor kappa B ($NF-{\kappa}B$) p65 and degradation of $I{\kappa}B-{\alpha}$. In addition, RGE increased the expression of heme oxygenase-1 (HO-1) in a dose-dependent manner, and the inhibitory effect of RGE on iNOS expression was abrogated by small interfering RNA-mediated knockdown of HO-1. Moreover, RGE induced nuclear translocation of nuclear factor E2-related factor 2 (Nrf2), a transcription factor that regulates HO-1 expression. Furthermore, the phosphoinositide-3-kinase (PI-3K) inhibitor and mitogen-activated protein kinase (MAPK) inhibitors suppressed RGE-mediated expression of HO-1, and RGE enhanced the phosphorylation of Akt, extracellular signal-regulated kinases (ERKs), p38, and c-JUN N-terminal kinases (JNKs). These results suggested that RGE suppressed the production of NO, a proinflammatory mediator, by inducing HO-1 expression via PI-3K/Akt- and MAPK-dependent signaling in LTA-stimulated microglia. The findings indicate that RGE could be used for the treatment of neuroinflammation induced by grampositive bacteria and that it may have therapeutic potential for various neuroinflammation-associated disorders.