OBJECTIVE: This study aimed to investigate the immuno-modulatory effects of agarwood leaf extract (ALE) derived from Aquilaria malaccensis using RAW264.7 murine macrophages.
METHODS: In this study, RAW264.7 macrophages were incubated with ALE alone for 26 hours or ALE for 2 hours, followed by bacterial lipopolysaccharide for 24 hours. The nitrite and cytokine production (tumour necrosis factor-alpha (TNFα), interleukin (IL)-1β, IL-6, and IL-10), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX2) expression in the macrophages were assayed.
RESULTS: The study showed that ALE alone was immunostimulatory on the macrophages by increasing the nitrite, TNFα, and IL-6 production and COX2 expression (p<0.05 vs. untreated unstimulated cells). Pre-treatment of ALE suppressed nitrite level and iNOS expression but enhanced TNFα and IL-6 production and COX2 expression (p<0.05 vs. untreated lipopolysaccharides (LPS)-stimulated cells). ALE also increased IL-10 production regardless of LPS stimulation (p<0.05 vs. untreated cells).
CONCLUSION: ALE was able to promote the immune response of macrophages by upregulating pro-inflammatory cytokine levels and COX2 expression. It also regulated the extent of the inflammation by reducing iNOS expression and increasing IL-10 levels. Thus, ALE may have a role in enhancing the innate immune system against infection; however, its validation from in vivo studies is still pending.
OBJECTIVE: This study investigates the cardioprotective effects of arjunolic acid (AA) via MyD88-dependant TLR4 downstream signaling marker expression.
MATERIALS AND METHODS: The MTT viability assay was used to assess the cytotoxicity of AA. LPS induced in vitro cardiovascular disease model was developed in H9C2 and C2C12 myotubes. The treatment groups were designed such as control (untreated), LPS control, positive control (LPS + pyrrolidine dithiocarbamate (PDTC)-25 µM), and treatment groups were co-treated with LPS and three concentrations of AA (50, 75, and 100 µM) for 24 h. The changes in the expression of TLR4 downstream signaling markers were evaluated through High Content Screening (HCS) and Western Blot (WB) analysis.
RESULTS: After 24 h of co-treatment, the expression of TLR4, MyD88, MAPK, JNK, and NF-κB markers were upregulated significantly (2-6 times) in the LPS-treated groups compared to the untreated control in both HCS and WB experiments. Evidently, the HCS analysis revealed that MyD88, NF-κB, p38, and JNK were significantly downregulated in the H9C2 myotube in the AA treated groups. In HCS, the expression of NF-κB was downregulated in C2C12. Additionally, TLR4 expression was downregulated in both H9C2 and C2C12 myotubes in the WB experiment.
DISCUSSION AND CONCLUSIONS: TLR4 marker expression in H9C2 and C2C12 myotubes was subsequently decreased by AA treatment, suggesting possible cardioprotective effects of AA.
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.