MATERIALS AND METHODS: An in vitro monocyte recruitment model utilizing THP-1 and HUVECs was developed to evaluate TNF-α-induced monocyte adhesion and trans-endothelial migration. To study the role of Nrf2 for MA-mediated anti-inflammatory effects, Nrf2 inhibitor ML385 was used as the pharmacological inhibitor. The expression of Nrf2, monocyte chemoattractant protein-1 (MCP-1), vascular cell adhesion molecule 1 (VCAM-1), cluster of differentiation 36 (CD36), and scavenger receptor type A (SR-A) in HUVECs and THP-1 macrophages were investigated using RT-qPCR and Western blotting. The NF-κB activity was determined using NF-κB (p65) Transcription Factor Assay Kit.
KEY FINDINGS: The results showed opposing effects of MA on Nrf2 expression in HUVECs and THP-1 macrophages. MA suppressed TNF-α-induced Nrf2 expression in HUVECs, but enhanced its expression in THP-1 macrophages. Combined effects of MA and ML385 suppressed MCP-1, VCAM-1, and SR-A expressions. Intriguingly, at the protein level, ML385 selectively inhibited SR-A but enhanced CD36 expression. Meanwhile, ML385 further enhanced MA-mediated inhibition of NF-κB activity in HUVECs. This effect, however, was not observed in THP-1 macrophages.
SIGNIFICANCE: MA attenuated foam cell formation by suppressing VCAM-1, MCP-1, and SR-A expression, as well as NF-κB activity, possibly through Nrf2 inhibition. The involvement of Nrf2 for MA-mediated anti-inflammatory effects however differs between HUVECs and macrophages. Future investigations are warranted for a detailed evaluation of the contributing roles of Nrf2 in foam cells formation.
AIM OF THE STUDY: To test extracts of P. glaucus in a number of bioassays and determine the legitimacy of its traditional use.
MATERIALS AND METHODS: The stems, leaves, roots and fruits of P. glaucus were collected and extracted sequentially with hexane, chloroform and ethanol, respectively. The anti-inflammatory activity was assessed by testing the ability of the extracts to inhibit heat induced protein denaturation, stabilise human red blood cells under hypotonic stress and by testing the inhibitory activity of the extracts against cyclooxygenases 1 and 2. Cytotoxicity was tested using the human lung epithelial cell line MRC-5 and nasopharangeal carcinoma cell line HK1 in the MTT assay.
RESULTS: Many of the samples showed an ability to prevent heat induced protein denaturation, as well as prevent lysis of red blood cells. Most of the extracts demonstrated inhibitory activity towards both of the COX enzymes. The ethanol extracts tended to demonstrate greater toxicity than other extracts, with some of the other extracts significantly enhancing growth and metabolism of the cells.
CONCLUSION: The benefit of P. glaucus for the treatment of diseases related to inflammation and cancer was supported by the in vitro assays adopted in this study.
AIM OF THE STUDY: This study explores the anti-inflammatory effect of TPTQ in silico, in vitro, and in vivo.
MATERIALS AND METHODS: In silico testing used the Gnina application, opened via Google Colab. The TPTQ structure was docked with the nuclear factor kappa B (NF-ĸB) protein (PDB: 2RAM). In vitro testing began with testing the cytotoxicity of TPTQ against Raw 264.7 cells, using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) method. A phagocytic activity test was carried out using the neutral red uptake method, and interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) secretion tests were carried out using the enzyme-linked immunosorbent assay (ELISA) method. In vivo, tests were carried out on mice by determining cluster of differentiation 8+ (CD8+), natural killer cell (NK cell), and IL-6 parameters, using the ELISA method.
RESULTS: TPTQ has a lower binding energy than the native ligand and occupies the same active site as the native ligand. TPTQ decreased the phagocytosis index and secretion of IL-6 and TNF-α experimentally in vitro. TPTQ showed significant downregulation of CD8+ and slightly decreased NK cells and IL-6 secretion in vivo.
CONCLUSION: The potent inhibitory effect of TPTQ on the immune response suggests that TPTQ can be developed as an anti-inflammatory agent, especially in the treatment of Covid-19.