Fucoxanthin decreases lipopolysaccharide-induced acute lung injury through the inhibition of RhoA activation and the NF-κB pathway

Fucoxanthin Ameliorates Vascular Remodeling via Attenuating Oxidative Stress in Hypoxic Pulmonary Hypertension Rats

Hypoxic pulmonary hypertension (HPH) is a fatal cardiopulmonary disease characterized by pulmonary vascular remodeling, primarily resulting from abnormal proliferation of pulmonary artery smooth muscle cells (PASMCs). Fucoxanthin, a natural carotenoid with potent antioxidant activity, was investigated for its therapeutic potential in HPH, given the critical role of oxidative stress in disease pathogenesis. In this study, Sprague-Dawley rats were exposed to intermittent chronic hypoxia for 4 weeks to mimic severe HPH. The results demonstrated that fucoxanthin significantly reduced the elevated right ventricular systolic pressure (RVSP), alleviated right ventricular hypertrophy, and mitigated pulmonary artery remodeling in the HPH rats. Additionally, fucoxanthin enhanced superoxide dismutase (SOD) activity and glutathione (GSH)/glutathione disulfide (GSSG) ratio while decreasing malondialdehyde (MDA) levels in both lung tissues and serum of HPH rats. In vitro, fucoxanthin inhibited cell proliferation and migration, decreased reactive oxygen species (ROS) production in hypoxia-induced PASMCs, and improved cell viability in hypoxia-induced endothelial cells (ECs). Importantly, fucoxanthin reduced hypoxia-inducible factor 1 alpha (HIF-1α) expression in both lung tissues and PASMCs under hypoxia. Notably, fucoxanthin exhibited effects similar to those of 2-methoxyestradiol (2ME2), an inhibitor of HIF-1α, on cell proliferation and ROS production in hypoxia-induced PASMCs. Moreover, fucoxanthin treatment did not significantly alter HIF-1α expression, cell proliferation, or ROS production after 2ME2 blocked HIF-1α. Collectively, fucoxanthin suppressed hypoxia-induced oxidative stress primarily by regulating the HIF-1α-ROS pathway, thereby alleviating pulmonary remodeling in HPH. Our findings represent a promising therapeutic strategy for HPH by improving pulmonary vascular remodeling.

Fucoxanthin ameliorates Propionibacterium acnes-induced ear inflammation in mice by modulating the IκBα/NF-κB signaling pathway and inhibiting NF-κB nuclear translocation

BACKGROUND

Acne vulgaris, a chronic inflammatory skin disorder, represents a pivotal research area in dermatology. Although fucoxanthin, a marine-derived carotenoid, displays potent anti-inflammatory activity, its therapeutic potential in acne pathogenesis remains underexplored.

OBJECTIVE

This study investigates fucoxanthin's effects on Propionibacterium acnes (P.acnes)-induced auricular inflammation in mice, focusing on its modulation of the IκBα/NF-κB signaling axis and inhibition of NF-κB nuclear translocation.

METHODS

Inflammation in the ear of mice was induced using a P.acnes injection model. The anti-inflammatory effects of fucoxanthin were verified by evaluating the levels of erythema, pathological damage, and inflammatory factors in the mice ear. An in vitro model was constructed to explore the regulatory mechanism of IkappaBalpha (IκBα)/nuclear factor-kappaB (NF-κB) pathway by fucoxanthin.

RESULTS

Fucoxanthin alleviated P. acnes-induced inflammatory pathology, reducing ear erythema. Mechanistically, it preserved IκBα stability, suppressed NF-κB nuclear translocation, and decreased proinflammatory cytokine production.

CONCLUSION

Fucoxanthin exerts anti-acne effects through coordinated inhibition of IκBα degradation and NF-κB nuclear translocation, establishing its potential as a targeted therapeutic agent for inflammatory acne.

Protective Effect of Hibifolin on Lipopolysaccharide-Induced Acute Lung Injury Through Akt Phosphorylation and NFκB Pathway

Acute lung injury (ALI) is a difficult condition to manage, especially when it is complicated by bacterial sepsis. Hibifolin, a flavonoid glycoside, has anti-inflammatory properties that make it a potential treatment for ALI. However, more research is needed to determine its effectiveness in LPS-induced ALI. In this study, male ICR mice were treated with hibifolin before LPS-induced ALI. Protein content and neutrophil count in bronchoalveolar lavage (BAL) fluid were measured by BCA assay and Giemsa staining method, respectively. The levels of proinflammatory cytokines and adhesive molecules were detected by ELISA assay. The expression of NFκB p65 phosphorylation, IκB degradation, and Akt phosphorylation was assessed by western blot assay. Hibifolin pre-treatment significantly reduced pulmonary vascular barrier dysfunction and neutrophil infiltration into the BAL fluid in LPS-induced ALI mice. In addition, LPS-induced expression of proinflammatory cytokines (IL-1β, IL-6, TNF-α) and adhesive molecules (ICAM-1, VCAM-1) within the BAL fluid were markedly reduced by hibifolin in LPS-induced ALI mice. More, hibifolin inhibited LPS-induced phosphorylation of NFκB p65, degradation of IκB, and phosphorylation of Akt in lungs with ALI mice. In conclusion, hibifolin shows promise in improving the pathophysiological features and proinflammatory responses of LPS-induced ALI in mice through the NFκB pathway and its upstream factor, Akt phosphorylation.

Kirenol ameliorates endotoxin-induced acute lung injury by inhibiting the ERK and JNK phosphorylation-mediated NFκB pathway in mice

Acute lung injury (ALI) is a pathological condition characterised by varying degrees of lung damage in patients. Kirenol exerts anti-inflammatory, immunosuppressive, and antioxidative effects. We investigated the protective effects of kirenol on lipopolysaccharide-induced ALI in mice. Pretreatment with kirenol significantly ameliorated lung oedema and neutrophil infiltration in ALI mice. Kirenol downregulated the chemokines (MIP-2) expression and the adhesion molecules (ICAM-1 and VCAM-1) secretion. Furthermore, kirenol inhibited the production of the proinflammatory mediators nitric oxide and prostaglandin (PG)E2 through the upstream factors iNOS and cyclooxygenase (COX)-2, respectively. Kirenol suppressed the IKK-IκB-NFκB pathway, which is involved in lipopolysaccharide-induced inflammation. Kirenol inhibited the lipopolysaccharide-induced phosphorylation of ERK and JNK, to a lesser extent, p38 MAPK and Akt. In conclusion, our findings suggest that kirenol exerts ameliorative effects against ALI by suppressing the production of chemokines, adhesion molecules, and proinflammatory mediators and inhibiting the IKK-IκB-NFκB pathway and its upstream factors, phosphorylated ERK and JNK.

Chrysanthemum Zawadskii Var. and Platycodon Grandifloras Extract Mixture Protects Against Lipopolysaccharide-Induced Pulmonary Inflammation and Cyclophosphamide-Induced Immune Deficiency: In Vivo Evidence

Respiratory tract diseases (RTDs) cause airflow limitations and impaired respiratory function, primarily due to pulmonary inflammation and immune dysfunction. Chrysanthemum zawadskii var. latilobum Kitamur and Platycodon grandifloras (CP) are traditional herbs known for their anti-inflammatory and immune-enhancing properties. This study investigates the anti-inflammatory and immune-enhancing effects of a combined extract of CP in vivo. CP was prepared by mixing equal volumes of Chrysanthemum zawadskii extract (CE) and Platycodon grandifloras extract (PE) at the same concentration. The anti-inflammatory effects of CP were evaluated using a lipopolysaccharide (LPS)-induced inflammation model in BALB/c mice. The immune-enhancing effects were assessed using a cyclophosphamide (CYP)-induced immunosuppression model. Protein and mRNA expressions of inflammatory and immune markers were analyzed through Western blotting and quantitative real-time PCR. CP significantly reduced LPS-induced pulmonary inflammation by decreasing interleukin (IL)-1β and cyclooxygenase-2 expression in lung tissues. In the CYP-induced model, CP treatment restored spleen and thymus weights, reversed reductions in immune cell counts, and increased TNF-α and IL-2 mRNA expression in the spleen. In conclusion, CP inhibits pulmonary inflammation by suppressing inflammatory mediators and enhances immune function by increasing immune-related indicators. This suggests that CP may have potential therapeutic applications for treating respiratory inflammation and related diseases.

Advance on the effects of algal carotenoids on inflammatory signaling pathways

The development of inflammation has an indispensable importance in the self-protection of the human body. However, over-inflammation may damage human health, and inflammatory pathways and inflammasomes have a significant impact on the onset of inflammation. Therefore, how to constrain the development of inflammation through inflammatory pathways or inflammasomes becomes a hot research issue. Carotenoids are a natural pigment and an active substance in algae, with anti-inflammatory and antioxidant effects. Many studies have shown that carotenoids have inhibitory effects on the inflammatory pathways and inflammasomes. In this review, we discussed the mechanism of carotenoids targeting those important inflammatory pathways and their effects on common inflammasome NLRP3 and inflammation-related diseases from the perspective of several inflammatory pathways, including p38 MAPK, IL-6/JAK/STAT3, and PI3K, with a focus on the targets and targeting effects of carotenoids on different inflammatory signaling pathways, and at last proposed possible anti-inflammatory targets.

Enhancing ocular protection against UVB: The role of irigenin in modulating oxidative stress and apoptotic pathways In Vivo

Oxidative damage contributes to age-related macular degeneration. Irigenin possesses diverse pharmacologic properties, including antioxidative and antiapoptotic effects. Our in vivo experiments indicated that irigenin mitigates UVB-induced histopathologic changes and oxidative DNA damage. Histologic analyses and TUNEL staining revealed that this compound dose-dependently ameliorated UVB-induced retinal damage and apoptosis. Furthermore, irigenin substantially reduced the level of 8-hydroxyguanosine, a biomarker of UVB-induced oxidative DNA damage. We further explored the molecular mechanisms that mediate the protective effects of irigenin. Our findings suggested that UVB-induced generation of ROS disrupts the stability of the mitochondrial membrane, activating intrinsic apoptotic pathways; the underlying mechanisms include the release of cytochrome c, activation of caspase-9 and caspase-3, and subsequent degradation of PARP-1. Notably, irigenin reversed mitochondrial disruption and apoptosis. It also modulated the Bax and Bcl-2 expression but influenced the mitochondrial apoptotic pathways. Our study highlights the role of the Nrf2 pathway in mitigating the effects of oxidative stress. We found that UVB exposure downregulated, but irigenin treatment upregulated the expression of Nrf2 and antioxidant enzymes. Therefore, irigenin activates the Nrf2 pathway to address oxidative stress. In conclusion, irigenin exhibits protective effects against UVB-induced ocular damage, evidenced by the diminution of histological alterations. It mitigates oxidative DNA damage and apoptosis in the retinal tissues by modulating the intrinsic apoptotic pathways and the AIF mechanisms. Furthermore, irigenin effectively reduces lipid peroxidation, enhancing the activity of antioxidant enzymes by stimulating the Nrf2 pathway. This protective mechanism underscores the potential benefit of irigenin in combating UVB-mediated ocular damage.

Hibifolin protected pro-inflammatory response and oxidative stress in LPS-induced acute lung injury through antioxidative enzymes and the AMPK2/Nrf-2 pathway

ALI is a grave medical ailment that manifests as abrupt inflammation of the lungs and diminished oxygen levels. It poses a considerable challenge to the medical fraternity, with elevated rates of morbidity and mortality. Our research endeavors to investigate the potential of hibifolin, a flavonoid glucuronide, imbued with potent antioxidant properties, and its molecular mechanism to combat LPS-induced ALI in mice. The study utilized ICR mice to create an ALI model induced by LPS. Prior to LPS administration, hibifolin was given at 10, 30, or 50 mg/kg, or dexamethasone was given at 1 mg/kg to assess its preventative impact. Changes in lung tissue, pulmonary edema, and lipid peroxidation were analyzed using H&E stain assay, lung wet/dry ratio assay, and MDA formation assay, respectively. Activity assay kits were used to measure MPO activity and antioxidative enzymes (SOD, CAT, GPx) activity in the lungs. Western blot assay was used to determine the phosphorylation of Nrf-2 and AMPK2 in the lungs. Hibifolin demonstrated a concentration-dependent improvement in LPS-induced histopathologic pulmonary changes. This treatment notably mitigated pulmonary edema, lipid peroxidation, and MPO activity in ALI mice. Additionally, hibifolin successfully restored antioxidative enzyme activity in the lungs of ALI mice. Moreover, hibifolin effectively promoted Nrf-2 phosphorylation and reinstated AMPK2 phosphorylation in the lungs of ALI mice. The results indicate that hibifolin could effectively alleviate the pathophysiological impact of LPS-induced ALI. This is likely due to its antioxidative properties, which help to restore antioxidative enzyme activity and activate the AMPK2/Nrf2 pathway. These findings are valuable in terms of enhancing our knowledge of ALI treatment and pave the way for further investigation into hibifolin as a potential therapeutic option for lung injuries.

Cyclizine-induced proinflammatory responses through Akt-NFκB pathway in macrophages

Cyclizine exhibits sedation and treatment of nausea, vomiting, and motion sickness due to antihistaminic and antimuscarinic effects. Cyclizine has the potential for abuse due to the hallucinogenic and euphoric effect. The response of overdose and illegal abuse of cyclizine includes confusion, tremors, chest pain, ataxia, seizures, and lead to suicide. Macrophage plays the important role in the innate immunity. However, over activation of macrophages results in pro-inflammatory responses in peripheral tissues. In the present study, cyclizine was found to enhanced the generation of pro-inflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6. We further found that secretion of nitrogen oxide (NO) induced by cyclizine via expression of inducible nitric oxide synthases (iNOS). Cyclizine exhibited parallel stimulation of phosphorylation of nuclear factor-κB (NFκB) p65, and its up-stream factor Akt. These results indicated that the expression of pro-inflammatory cytokines, pro-inflammatory mediators, and adhesion molecules would be induced by cyclizine via activation of Akt-NFκB pathway in macrophages.

Circ_0040994 depletion alleviates lipopolysaccharide-induced HK2 cell injury through miR-17-5p/TRPM7 axis

BACKGROUND

Sepsis is a fatal systemic inflammatory disease that causes septic acute kidney injury (AKI). In this work, we explored the roles of circ_0040994 in lipopolysaccharide (LPS)-induced human kidney-2 (HK2) cell injury.

METHODS

Circ_0040994, miR-17-5p and transient receptor potential melastatin 7 (TRPM7) expression were detected by qRT-PCR. Cell functions were examined by MTT assay, flow cytometry assay, western blot, ELISA assay, and oxidative stress assay. The molecular association was detected by dual-luciferase reporter assay.

RESULTS

Circ_0040994 was upregulated in the serum of septic AKI patients in comparison with the serum of healthy controls. Silencing circ_0040994 enhanced cell viability but inhibited cell apoptosis, cell inflammation and oxidative stress in LPS-triggered HK2 cells. Circ_0040994 acted as a miR-17-5p sponge to regulate the level of TRPM7. Moreover, miR-17-5p could alleviate LPS-induced HK2 cell injury by suppressing TRPM7.

CONCLUSION

Circ_0040994 downregulation alleviated LPS-induced HK2 cell injury through the miR-17-5p/TRPM7 axis.

Nutritional and Health Benefits of the Brown Seaweed Himanthalia elongata

Himanthalia elongata is a brown seaweed containing several nutritional compounds and bioactive substances including antioxidants, dietary fibre, vitamins, fatty acids, amino acids, and macro- and trace- elements. A variety of bioactive compounds including phlorotannins, flavonoids, dietary fucoxanthin, hydroxybenzoic acid, hydroxycinnamic acid, polyphenols and carotenoids are also present in this seaweed. Multiple comparative studies were carried out between different seaweed species, wherein H. elongata was determined to exhibit high antioxidant capacity, total phenolic content, fucose content and potassium concentrations compared to other species. H. elongata extracts have also shown promising anti-hyperglycaemic and neuroprotective activities. H. elongata is being studied for its potential industrial food applications. In new meat product formulations, it lowered sodium content, improved phytochemical and fiber content in beef patties, improved properties of meat gel/emulsion systems, firmer and tougher with improved water and fat binding properties. This narrative review provides a comprehensive overview of the nutritional composition, bioactive properties, and food applications of H. elongata.

Apigenin attenuates inflammatory response in allergic rhinitis mice by inhibiting the TLR4/MyD88/NF-κB signaling pathway

BACKGROUND

Allergic rhinitis (AR) is an immunoglobulin E (IgE)-mediated immune inflammatory response that mainly affects the nasal mucosa. Currently, there is evidence that apigenin, as a flavonoid, has anti-allergic potential.

MATERIAL/METHODS

In vitro, compound 48/80 and lipopolysaccharide (LPS) were used to induce mast cell activation and inflammation in HMC-1 cells. In vivo, ovalbumin (OVA) induced and stimulated AR in BALB/c mice. ELISA was used to detect the contents of β-hexosaminidase, histamine, eosinophil cationic protein (ECP), OVA-specific IgE, IgG1, and IgG2a, inflammatory factors in cells and mouse serum. Cell viability and apoptosis were measured with MTT and flow cytometry. Toll like receptor 4 (TLR4)/myeloid differentiation factor88 (MyD88)/Nuclear transcription factor-κB (NF-κB) pathway-related proteins in cells and mouse nasal mucosa tissues were analyzed with Western blotting. The levels of Th1 (IFN-γ) and Th2 (IL-4, IL-5, and IL-13) cytokines and Th1 (T-bet) and Th2 (GATA-3) specific transcription factors were also assessed. The ratio of Th1 (CD4⁺ IFN-γ⁺ ) / Th2 (CD4⁺ IL-4⁺ ) cells in mouse peripheral blood mononuclear cells was evaluated by flow cytometry.

RESULTS

Apigenin significantly inhibited compound 48/80-induced secretion of β-hexosaminidase and histamine. Apigenin blocked LPS-induced decrease in cell viability and increase in cell apoptosis and inflammatory cytokine secretion by suppressing the activity of the TLR4/MyD88/NF-κB pathway. Apigenin treatment reduced the levels of OVA-specific IgE, IgG1 and IgG2a as well as β-hexosaminidase, histamine and ECP levels in mouse serum. Moreover, administration with apigenin decreased Th2 cytokine and transcription factor levels and increased Th1 cytokine and transcription factor levels, and promoted the ratio of Th1/Th2 cells in AR mice. Additionally, apigenin significantly alleviated nasal symptoms and nasal eosinophil infiltration in AR mice.

CONCLUSIONS

Apigenin alleviates the inflammatory response of allergic rhinitis by inhibiting the activity of the TLR4/MyD88/NF-κB signaling pathway.

Fucoxanthin ameliorates oxidative injury and inflammation of human bronchial epithelial cells induced by cigarette smoke extract via the PPARγ/NF‑κB signaling pathway

Chronic obstructive pulmonary disease (COPD) is a prevalent and long-term airway disease. It has been reported that fucoxanthin (FX) exhibits anti-inflammatory and antioxidant effects. However, the underlying mechanism of FX in COPD remains unknown. Therefore, to investigate the effect of FX on COPD, BEAS-2B cells were treated with cigarette smoke extract (CSE). The viability of BEAS-2B cells treated with increasing doses of FX was assessed by Cell Counting Kit-8. Lactate dehydrogenase (LDH) levels were measured using a corresponding kit. In addition, ELISA was carried out to detect the content of TNF-α, IL-1β and IL-6. Additionally, a TUNEL assay and western blot analysis were performed to assess the cell apoptosis rate. Furthermore, 2',7'-dichlorodihydrofluorescein diacetate was used to measure reactive oxygen species levels, while the contents of oxidative stress-associated indexes were determined using the corresponding kits. Bioinformatics analysis using the search tool for interactions of chemicals database predicted that peroxisome proliferator-activated receptor γ (PPARγ) may be a target of FX. The binding capacity of FTX with PPARγ was confirmed by molecular docking. The protein expression levels of the PPARγ/NF-κB signaling-associated factors were detected by western blot analysis. Finally, the regulatory mechanism of FX in COPD was revealed following cell treatment with the PPARγ inhibitor, T0070907. The results demonstrated that FX enhanced CSE-induced BEAS-2B cell viability and attenuated CSE-induced BEAS-2B cell inflammation and oxidative damage, possibly via triggering PPARγ/NF-κB signaling. Pre-treatment of BEAS-2B cells with the PPARγ inhibitor, T0070907, could reverse the protective effects of FX on CSE-induced BEAS-2B cells. Overall, the present study suggested that FX could ameliorate oxidative damage as well as inflammation in CSE-treated human bronchial epithelial in patients with COPD via modulating the PPARγ/NF-κB signaling pathway.

Downregulation of circ-ZNF644 alleviates LPS-induced HK2 cell injury via miR-335-5p/HIPK1 axis

Circular RNA (circRNA) has been confirmed to be involved in regulating sepsis-induced acute kidney injury (AKI). Our research aims to explore circ-ZNF644 role in the development of sepsis-induced AKI. Lipopolysaccharide (LPS) was used to induce kidney tubular epithelial cell (HK2) injury. ELISA assay was performed to measure the concentrations of inflammation factors. Cell functions were determined by cell counting kit 8 assay, EdU assay and flow cytometry. Protein expression was evaluated by Western blot analysis. Quantitative real-time PCR was used to detect relative expression of circ-ZNF644, miR-335-5p and homeodomain-interacting protein kinase 1 (HIPK1). RNA interaction was confirmed by dual-luciferase reporter assay and RIP assay. LPS enhanced HK2 cell inflammation, oxidative stress, apoptosis, and reduced proliferation. Circ-ZNF644 was overexpressed in sepsis-induced AKI patients. Circ-ZNF644 knockdown suppressed LPS-induced HK2 cell injury, and this effect could be revoked by miR-335-5p inhibitor. MiR-335-5p was sponged by circ-ZNF644, and its expression was downregulated in sepsis-induced AKI patients. HIPK1 was targeted by miR-335-5p, and its expression could be suppressed by circ-ZNF644 knockdown. MiR-335-5p had an inhibition effect on HK2 cell injury induced by LPS, and HIPK1 overexpression could reverse this effect. Circ-ZNF644 knockdown relieved LPS-induced HK2 cell injury through the miR-335-5p/HIPK1 axis, confirming that circ-ZNF644 contributed to sepsis-induced AKI.