Robust and efficient control of therapeutic gene expression is needed for timing and dosing of gene therapy drugs in clinical applications. Ribozyme riboswitch provides a promising building block for ligand-controlled gene-regulatory system, based on its property that exhibits tunable gene regulation, design modularity, and target specificity. Ribozyme riboswitch can be used in various gene delivery vectors. In recent years, there have been breakthroughs in extending ribozyme riboswitch's application from gene-expression control to cellular function and fate control. High throughput screening platforms were established, that allow not only rapid optimization of ribozyme riboswitch in a microbial host, but also straightforward transfer of selected devices exhibiting desired activities to mammalian cell lines in a predictable manner. Mathematical models were employed successfully to explore the performance of ribozyme riboswitch quantitively and its rational design predictably. However, to progress toward gene therapy relevant applications, both precision rational design of regulatory circuits and the biocompatibility of regulatory ligand are still of crucial importance.

Objective To investigate the inhibitory effect of gallic acid(GA)on lipopolysaccharide(LPS)-induced inflammatory responses in human THP1 macrophages.Methods THP1 monocytes were differentiated into macrophages with phorbol myristate acetate.A macrophage inflammation model was established with LPS induction,and GA was added at different concentrations.The safe concentrations of LPS and GA for THP1 cells were screened using the CCK-8 method,and a normal group,model group(100 μg/L LPS),and GA group(100 μg/L LPS+different concentrations of GA)were set up.ELISA was used to detect the levels of interleukin(IL)-6,tumor necrosis factor-α(TNF-α),and IL-1β in the cell culture media of each group.The microplate method was used to detect lactate dehydrogenase(LDH)activity and NO content in the cell cultures,and fluorescence staining was used to detect the reactive oxygen species(ROS)levels,cell damage,and changes in mitochondrial transmembrane potential in each group.Western blot was performed to detect the levels of cyclooxygenase-2(COX-2),HMGB1,c-Jun amino-terminal kinase(JNK),extracellular-regulated protein kinase(ERK),P38 mitogen-activated protein kinase(P38),nuclear transcription factor-KB(NF-κB),NOD-like receptor protein 3(NLRP3),Caspase-1,IL-1β,and gasdermin D(GSDMD).Results Compared with the normal group,the model cell group's secretion of IL-6,TNF-α,IL-1β,and NO was increased(P＜0.05);the secretion of COX-2,HMGB1,p-ERK,p-JNK,and p-P38 and expression of p-NF-KB,NLRP3,Caspase-1,IL-1β were elevated(P＜0.05);expression of GSDMD protein activation fragment was reduced(P＜0.05);ROS generation and cellular damage were significantly increased;mitochondrial transmembrane potential was significantly lower;and LDH activity was elevated(P＜0.05).In comparison with the model group,the GA group cells'secretion of IL-6,TNF-α,IL-1β,and NO was decreased(P＜0.05);expression of COX-2,HMGB1,p-ERK,p-JNK,p-P38,p-NF-κB,NLRP3,Caspase-1,and IL-1β was decreased(P＜0.05);GSDMD protein activation fragment expression level was increased(P＜0.05);ROS generation and cellular damage were decreased;mitochondrial transmembrane potential gradually increased;and LDH activity was decreased(P＜0.05).Conclusions GA had an inhibitory effect on the LPS-induced inflammatory response in THP1 macrophages,and its anti-inflammatory mechanism may involve the MAPK and NF-κB signaling pathways.

Objective:To discuss the effect of Boschnikia rossica polysaccharides rapa polysaccharides(BRPS)on lipopolysaccharide(LPS)-induced inflammatory responses in the THP-1 macrophages,and to clarify its mechanism.Methods:The THP-1 monocytes were differentiated into the macrophages,and the inflammation model was established using LPS to induce the THP-1 macrophages.CCK-8 method was used to detect the survial rates of the THP-1 macrophages after treated with different concentrations(0,100,200,500,1 000,and 2 000 μg·L-1)of LPS and different concentrations(0,12.5,25.0,50.0,100.0,and 200.0 mg·L-1)of BRPS to select the concentrations for the subsequent experiments.The THP-1 macrophages were divided into blank group,model group,low dose of BRPS group(25.0 mg·L-1 BRPS),medium dose of BRPS group(50.0 mg·L-1 BRPS),and high dose of BRPS group(100.0 mg·L-1 BRPS).P38 inhibitor SB203580,ERK inhibitor U0126,c-Jun N-terminal kinase(JNK)inhibitor SP600125,and nuclear factor of kappa B(NF-κB)inhibitor BAY11-7082 were used to verify the effects on THP-1 cells.The THP-1 cells were divided into control group,LPS group,inhibitor group,100.0 mg·L-1 BRPS group,and inhibitor+100.0 mg·L-1 BRPS group.ELISA method was used to detect the levels of tumor necrosis factor α(TNF-α),interleukin(IL)-6,and IL-1β in culture fluid of the THP-1 macrophages in various groups;DCFH-DA fluorescence probe method was used to detect the reactive oxygen species(ROS)levels in the THP-1 macrophages in various groups;Hoechst33342/PI fluorescence staining method was used to detect the membrane damage in the THP-1 macrophages in various groups;JC-1 fluorescence staining was used to observe mitochondrial membrane potential in the THP-1 macrophages in various groups;Western blotting method was used to detect the expression levels of cyclooxygenase-2(COX-2),high mobility group protein B1(HMGB1),NOD-like receptor thermal protein domain assciated protein 3(NLRP3),cysteinyl aspartate specific protease(Caspase)-1,gasdermin D(GSDMD)-N,IL-1β,mitogen-activated protein kinase(MAPK),and nuclear factor-kappa B(NF-κB)related proteins in the THP-1 macrophages in various groups.Results:The CCK-8 method results showed that when the LPS concentration was 100-2 000 μg·L-1,the survival rates of the THP-1 macrophages were over 90%.Compared with 0 μg·L-1 LPS group,the IL-6 levels in culture fluid of the THP-1 macrophages in 100,200,500,1 000,and 2 000 μg·L-1 LPS group were increased(P<0.05),indicating a significant enhancement of the inflammatory response in the macrophages,so 100 μg·L-1 LPS was used to construct the inflammation model.After treated with 12.5,25.0,50.0,100.0,and 200.0 mg·L-1 BRPS,the survival rates of the THP-1 macrophage were 91.2%,93.8%,91.4%,90.6%,and 91.8%,respectively,so 25.0,50.0,and 100.0 mg·L-1 BRPS were selected as the drug concentrations for low,medium,and high doses of BRPS groups in the subsequent experiments.The ELISA results showed that compared with blank group,the levels of IL-6,TNF-α,and IL-1β in culture fluid of the THP-1 macrophages in model group were increased(P<0.05);compared with model group,the levels of IL-6,TNF-α,and IL-1β in low,medium,and high doses of BRPS groups were decreased(P<0.05).The DCFH-DA fluorescence probe method results showed that compared with blank group,the ROS level in the THP-1 macrophages in model group was increased(P<0.05);compared with model group,the ROS levels in low,medium,and high doses of BRPS groups were decreased(P<0.05).The Hoechst33342/PI fluorescence staining results showed that compared with blank group,the degree of membrane damage in the THP-1 macrophages in model group was increased;compared with model group,the degrees of membrane damage in low,medium,and high doses of BRPS groups were decreased.The JC-1 fluorescence staining results showed that compared with blank group,the mitochondrial membrane potential in the THP-1 macrophages in model group was decreased significantly;compared with model group,the mitochondrial membrane potential in low,medium,and high doses of BRPS groups were increased gradually.The Western blotting results showed that compared with blank group,the expression levels of COX-2,HMGB1,NLRP3,Caspase 1,GSDMD-N,and IL-1β proteins and the ratios of p-P38/P38,p-ERK/ERK,p-JNK/JNK,and p-NF-κB/NF-κB in the THP-1 macrophages in model group were increased(P<0.05);compared with model group,the expression levels of HMGB1,NLRP3,Caspase-1,GSDMD-N,and IL-1β proteins and the ratios of p-P38/P38,p-ERK/ERK,p-JNK/JNK,and p-NF-κB/NF-κB in the THP-1 macrophages in medium and high doses of BRPS groups were decreased(P<0.05),the expression levels of NLRP3,Caspase-1,and IL-1β proteins in the cells in low dose of BRPS group were decreased(P<0.05),the expression level of COX-2 protein in the cells in high dose of BRPS group was decreased(P<0.05).Compared with control group,the ratios of p-P38/P38,p-ERK/ERK,p-JNK/JNK,and p-NF-κB/NF-κB,and the expression level of IL-1β protein in the THP-1 macrophages in LPS group were increased(P<0.05);compared with LPS group,the ratios of p-P38/P38,p-ERK/ERK,p-JNK/JNK,and p-NF-κB/NF-κB,and the expression level of IL-1β protein in the THP-1 macrophages in inhibitor group,100 mg·L-1 BRPS group,and inhibitor+100 mg·L-1 BRPS group were decreased(P<0.05);compared with inhibitor group,the ratios of p-P38/P38,p-ERK/ERK,p-JNK/JNK,and p-NF-κB/NF-κB in the THP-1 macrophages in inhibitor+100 mg·L-1 BRPS group were decreased(P<0.05).Conclusion:BRPS inhibits the inflammatory response of the THP-1 macrophages,which may be related to the MAPK and NF-κB signaling pathways regulated by BRPS.