ABSTRACT
Despite covalent adaptable networks (CANs) imparting the favorable features of crosslinked polymers, as well as the functionality of reprocessing, reshaping and welding, due to exchange reaction enabled topology changes; it is still a huge challenge to design catalyst-free, fast reprocessing, controlled degradation and polymer recyclable biomass base CANs. Herein, for the first time, acetal-based covalent adaptable cellulose networks (ACCs) were utilized to synthesize readily reconstructable cellulose-based thermosets with mechanical tunability. ACCs were synthesized via catalyst-free "click" addition of cellulose and divinyl ether without releasing small molecule byproducts. Different crosslinking densities and crosslinkers were used to explore the structure-property relationship, the mechanical and thermal properties of the ACCs were strongly influenced by these factors. ACCs can obtain enhanced tensile strength or elongation at break by changing the structure of the crosslinker. Furthermore, the reworking, welding and shape memory properties of these ACCs, based on the dynamic exchange reaction of acetal bonds, were investigated. In addition, these ACCs can be degraded under acidic conditions, and closed-loop utilization of polymer was possible. Thus, ACCs can be mechanically and chemically double-cycled, which will contribute to solving the white pollution problem and resource waste as a new class of sustainable plastics.
Subject(s)
Acetals , Cellulose , Polymers , Biomass , Environmental PollutionABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Panlongqi Tablet is prepared with the ancestral secret recipe provided by Mr. Wang Jiacheng, a famous specialist in orthopedics and traumatology of China. The efficacy and safety of PLQT have been supported by years of clinical practice in the treatment of joint-related conditions. Has remarkable effect for treating rheumatoid arthritis (RA) clinically. However, its mechanism is not entirely clear. AIM OF THE STUDY: We aim to evaluate the anti-inflammatory activity of PLQT and explore its mechanism in adjuvant-induced arthritis (AA) mice and LPS-induced Human fibroblast-like synovial (HFLS) cells. MATERIALS AND METHODS: To this end, we analyzed the active ingredients in PLQT by HPLC-MS/MS. Furthermore, the anti-RA effect of PLQT was studied through proliferation, apoptosis, foot swelling, cytokine levels, immune organ index, histopathology and related signal pathways in LPS-induced HFLS cells and AA-treated mice. RESULTS: HPLC-MS/MS results showed that PLQT contained a variety of active compounds, such as epicatechin, imperatorin, hydroxysafflor yellow A and so on. PLQT significantly inhibited the abnormal proliferation of HFLS cells induced by LPS, promoted cell apoptosis. In AA-treated mice, PLQT alleviated RA symptoms by alleviating paw swelling, synovial hyperplasia, pannus formation, inflammatory cell infiltration, and inhibiting abnormal immune responses. The results showed that PLQT significantly decreased the expression of inflammatory mediators (IL-1ß, IL-6, IL-17) in vivo and in vitro, which may be related to the regulation of PI3K/Akt, MAPK and JAK/STAT signaling pathways. CONCLUSION: Based on serum pharmacology and in vivo pharmacology studies, PLQT may regulate RA symptoms by regulating inflammatory and immune response-related pathways, which is an effective method for the treatment of RA.
Subject(s)
Arthritis, Experimental , Arthritis, Rheumatoid , Humans , Mice , Animals , Lipopolysaccharides , Phosphatidylinositol 3-Kinases , Tandem Mass Spectrometry , Arthritis, Rheumatoid/drug therapy , Arthritis, Experimental/drug therapyABSTRACT
Hypertension affects 30% of adults and is the leading risk factor for cardiovascular disease. Kidney sodium reabsorption plays a vital role in the initial stage and development of essential hypertension. It has been extensively reported that the variants of kidney ion handling genes are associated to blood pressure, and clinical features of hypertension. However, the underlying mechanisms by which these variants alter protein function are rarely summarized. In addition, the variation of one single gene is often limited to induce a significant effect on blood pressure. In the past few decades, the influence by genes × genes (G × G) and/or genotype × environment (G × E) interactions on a given trait, for example, blood pressure, have been widely considered, especially in studies on polygenic genetic traits. In the present review, we discuss the progress in genetics studies on kidney ion handling genes, encoding Na+ channels (Na+-Cl- cotransporter [NCC], Na-K-2Cl cotransporter [NKCC2], epithelial Na+ channels [ENaCs]), K+ channel (renal outer medullary potassium channel [ROMK]), and Cl- channels (Pendrin, chloride voltage-gated channel Kb [CLC-Kb]), respectively, and their upstream kinases, WNKs and SGK1. We seek to clarify how these genes are involved in kidney sodium absorption and influence blood pressure, especially emphasizing the underlying mechanisms by which genetic variants alter protein functions and interaction in blood pressure regulation. The present review aims to enhance our understanding of the important role of kidney ion handling genes/channels in blood pressure control.
Subject(s)
Hypertension , Kidney , Adult , Humans , Blood Pressure/genetics , Kidney/metabolism , Sodium , Sodium-Potassium-Chloride Symporters , Solute Carrier Family 12, Member 3ABSTRACT
BACKGROUND: Panlongqi Tablet (PLQT) is a Chinese patent drug composed of 29 kinds of traditional Chinese medicines. Clinical practice has shown that PLQT can relieve osteoarthritis-caused joint pain, but its effects and mechanisms in other pathological links of osteoarthritis have not been characterized. PURPOSE: The purpose of this study is to reposition the pharmacodynamic effects of PLQT through network pharmacology analysis combined with experimental validation, and also to preliminarily explore its possible mechanism. METHODS: On the basis of integrating the relevant targets of PLQT in multiple drug databases and osteoarthritis-related targets in the disease database, an interaction network of related genes was constructed. The hub candidate targets of PLQT in the treatment of osteoarthritis were determined by calculating the main network topological characteristics, The specific functions and pathways of these targets acting on osteoarthritis were modularly analyzed. In addition, the modified Hulth-induced rat model of osteoarthritis and IL-1ß-induced in vitro model of osteoarthritis were established to further validate the potential efficacy and possible mechanism of PLQT. RESULTS: A total of 138 key targets related to osteoarthritis were selected based on topological parameters, and their biological functions were mainly enriched in four over-expressed modules of cartilage degeneration, inflammatory response, immune response, and subchondral bone metabolism. The hub candidate targets had the highest enrichment degree in the TLR4-RAC1-PIK3CA-Akt-NFκB signaling axis of the PI3K/Akt signaling pathway. In vivo results showed that PLQT treatment significantly inhibited the degeneration of proteoglycan and collagen in the cartilage of osteoarthritis rats, suppressed chondrocyte apoptosis, and reduced the Mankin score of joints. Moreover, PLQT alleviated synovial inflammation, reduced the Krenn score of synovium, inhibited the formation of osteophytes in osteoarthritis rats, reduced the bone mineral density (BMD), fractional bone volume (BV/TV), and trabecular thickness (Tb.Th.), as well as increased the trabecular separation (Tb.Sp.) of subchondral bone and the thickness of the subchondral bone plate (SBP.Th.). PLQT suppressed the expressions of TLR4, RAC1, PIK3CA, p-Akt, MMP-13, and ADAMTS-5 in the cartilage, and inhibited the expression of NFκB p65 in the chondrogenic nucleus. Meanwhile, as downstream effector factors of the predictive pathways, the levels of serum interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), nitric oxide (NO), and prostaglandin E2 (PGE2) were decreased after PLQT treatment. In vitro results also showed that PLQT could inhibit the expression of key proteins and downstream effector factors of the signaling axis, and this inhibition disappeared when pathway agonists were added. CONCLUSION: PLQT exerted pharmacological effects on the key pathological links of osteoarthritis including chondrocyte apoptosis, extracellular matrix degradation, inflammation, and subchondral bone metabolism by inhibiting the TLR4-RAC1-PIK3CA-Akt-NFκB axis-related proteins.
Subject(s)
Osteoarthritis , Toll-Like Receptor 4 , Animals , Class I Phosphatidylinositol 3-Kinases , Drugs, Chinese Herbal , Inflammation , NF-kappa B , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , RatsABSTRACT
Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by inflammation infiltration of the synovial tissues and the fibroblast-like synoviocytes. Tectoridin is a botanical active ingredient with anti-inflammatory properties. In this study, the anti-arthritic effects of tectoridin and its mechanism of action are examined in TNF-α-induced human fibroblast-like synovial cells (HFLSs cells) and complete Freund's adjuvant (CFA)-stimulated arthritic mice. Arthritis progression was evaluated via bodyweight, hind paw swelling, organ index, and synovial pathology. IL-1ß, IL-6 and other pro-inflammatory factors concentrations, and the expression of MAPK pathway proteins in HFLSs cells and arthritic mice were measured using ELISA and western blotting. Results showed that tectoridin significantly decreased the swelling of the paws and joints as well as the increased immune organ index within CFA-induced arthritic mice. Histopathological analysis showed that tectoridin alleviated the lesions of ankle joints and synovial tissues induced by CFA. Secretion of pro-inflammatory cytokines in TNF-α-induced HFLSs cells and CFA-stimulated arthritic mice were also abated by tectoridin. Similarly, the presence of tectoridin significantly inhibited the abnormal phosphorylation levels of ERK, JNK, and p38 in vivo and in vitro. All those results highlighted that tectoridin exhibits anti-arthritis effects by inhibiting MAPK-mediated inflammatory responses.
Subject(s)
Arthritis, Experimental , Arthritis, Rheumatoid , Animals , Arthritis, Experimental/chemically induced , Arthritis, Experimental/drug therapy , Arthritis, Rheumatoid/drug therapy , Cytokines/metabolism , Edema/chemically induced , Edema/drug therapy , Edema/pathology , Freund's Adjuvant/adverse effects , Humans , Isoflavones , Mice , Tumor Necrosis Factor-alpha/adverse effectsABSTRACT
Tectoridin, isolated from the dry rhizome of iris, is a compound with multiple biological activities. However, its biological roles in rheumatoid arthritis (RA) have still not been clearly elucidated. The aim of this study was to focus on the effects of tectoridin on tumor necrosis factor (TNF)-α-induced human fibroblastlike synoviocyte rheumatoid arthritis (HFLSRA) cells, and its associated mechanisms. After TNF-α stimulation, CCK8 and MTT assays, TUNEL assay and flow cytometry, Western blotting and immunohistochemistry analysis were performed to check the cell proliferation, cell apoptosis and cycle analysis, and the expression of related proteins, respectively. Our results showed that tectoridin significantly hindered cell proliferation, S-to-G2/M phase transition and down-regulated Cyclind 1 and PCNA protein levels. Additionally, tectoridin markedly promoted apoptosis rates of HFSL-RA cells and elevated the expression levels of Cleaved Caspase-3 and Bax, while reduced the expression level of Bcl-2. Moreover, tectoridin reversed TNF-α-induced overexpression of MMPs and factors associated with the TLR4/NLRP3/NF-κB pathway. We conclude that tectoridin ameliorated TNF-α-induced proliferation and inflammation by inhibiting TLR4/NLRP3/NF-κB pathway. It might provide a new insight for the clinical application of RA.
Subject(s)
Arthritis, Rheumatoid , NF-kappa B , Apoptosis , Arthritis, Rheumatoid/metabolism , Cell Proliferation/physiology , Cells, Cultured , Humans , Inflammation/drug therapy , Inflammation/pathology , Isoflavones , NF-kappa B/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Signal Transduction , Toll-Like Receptor 4 , Tumor Necrosis Factor-alpha/pharmacologyABSTRACT
BACKGROUND: Tectoridin, widely extracted and separated from the rhizome of Iris tectorum Maxim, is extensively reported to have affluent bioactivity, but rarely reported to have anti-inflammatory effects. In this study, we aim to investigate the anti-inflammatory effects and the underlying mechanisms of tectoridin. METHODS: Here, RAW264.7 macrophages were stimulated with Lipopolysaccharide (LPS) for the inflammation model in vitro. Experimental animals received tectoridin and Dexamethasone (DEX) before LPS injection for endotoxic shock mouse model in vivo. The pro-inflammatory mediators and cytokines in the cell supernatant and serum were detected by ELISA kits. The tissue damages were assessed by biochemical indexes and H&E staining. Immunohistochemistry and Western blot were performed for the detection of proteins. RESULTS: Our data showed that tectoridin attenuated the LPS-up-regulated nitric oxide (NO), interleukin-6 (IL-6), and interleukin-18 (IL-18) from macrophages and tumor necrosis factor-α (TNF-α); (IL-6) and (IL-1ß) in the serum levels. Besides, our histopathological study showed that the damages caused by LPS in the lung, liver, and kidney tissues were decreased. Furthermore, our results demonstrated that tectoridin inhibited the activation of TLR4-NF-κB/NLRP3 signaling proved by immunohistochemistry assay and Western blot. CONCLUSION: Taken all together, tectoridin might have the potential ability of anti-inflammatory effects and the possible mechanism may be relevant to its inhibition of TLR4-NF-κB/NLRP3 signaling.
Subject(s)
Lipopolysaccharides , NF-kappa B , Animals , Anti-Inflammatory Agents/pharmacology , Cytokines/metabolism , Dexamethasone/pharmacology , Inflammation/chemically induced , Inflammation/drug therapy , Inflammation/metabolism , Inflammation Mediators/metabolism , Interleukin-18 , Interleukin-6 , Isoflavones , Lipopolysaccharides/toxicity , Mice , NF-kappa B/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Nitric Oxide/metabolism , Toll-Like Receptor 4/metabolism , Tumor Necrosis Factor-alphaABSTRACT
Alkylbenzenes have a wide range of uses and are the most demanded aromatic chemicals. The finite petroleum resources compels the development of production of alkylbenzenes by non-petroleum routes. One-pass selective conversion of benzene and syngas to alkylbenzenes is a promising alternative coal chemical engineering route, yet it still faces challenge to industrialized applications owing to low conversion of benzene and syngas. Here we presented a Cu-ZnO-Al2O3/ZSM-5 bifunctional catalyst which realizes one-pass conversion of benzene and syngas to alkylbenzenes with high efficiency. This bifunctional catalyst exhibited high benzene conversion (benzene conversion of 50.7%), CO conversion (CO conversion of 55.0%) and C7&C8 aromatics total yield (C7&C8 total yield of 45.0%). Characterizations and catalytic performance evaluations revealed that ZSM-5 with well-regulated acidity, as a vital part of this Cu-ZnO-Al2O3/ZSM-5 bifunctional catalyst, substantially contributed to its performance for the alkylbenzenes one-pass synthesis from benzene and syngas due to depress methanol-to-olefins (MTO) reaction. Furthermore, matching of the mass ratio of two active components in the dual-function catalyst and the temperature of methanol synthesis with benzene alkylation reactions can effectively depress the formation of unwanted by-products and guarantee the high performance of tandem reactions. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10562-021-03617-5.
ABSTRACT
(-)-Epicatechin gallate (ECG), as a compound in green tea extract polyphenols, has specific therapeutic effects against oxidative stress. Oxidative stress exists throughout the pathological development of atherosclerosis. In this study, two atherosclerosis models, oxidized low-density lipoprotein (ox-LDL)-induced vascular smooth muscle cells (VSMCs) and high fat diet (HFD)-induced ApoE-/- mice, were applied to explore the mechanism of ECG intervention on AS. In vivo and in vitro studies showed that ECG reduced the level of MDA and increased the activity of SOD, which are oxidative stress factors. ECG also improved HFD-induced disorder of lipid factor expression in the serum of ApoE-/- mice and alleviated oxidative stress by enhancing the antioxidant activity. The potential mechanism was supposed to be the inhibition of the phosphorylation of p65 by ECG in the NF-κB pathway in the aorta, thereby blocking the expression of inflammatory mediators. In addition, ECG increased the stability of atherosclerosis plaques by reducing the expression of MMP-2 and ICAM-1 in atherosclerosis diseased tissues. ECG reduced lipid accumulation in the aorta and its roots and also plaque neoplasia. Western blotting experiments indicated that ECG increased the nuclear transfer of Nrf2 and the expression of heme oxygenase 1 (HO-1) was increased. These results demonstrated that ECG significantly reduced the formation of aortic plaque in ApoE-/- mice which was possibly triggered by the inhibition of hyperlipidemia and oxidative stress that exhibited the anti-atherosclerotic potential.
Subject(s)
Atherosclerosis/prevention & control , Catechin/analogs & derivatives , Myocytes, Smooth Muscle/metabolism , Oxidative Stress , Plaque, Atherosclerotic/prevention & control , Animals , Apolipoproteins E/genetics , Atherosclerosis/metabolism , Atherosclerosis/pathology , Catechin/pharmacology , Cholesterol/blood , Diet, High-Fat , Heme Oxygenase-1/metabolism , Inflammation Mediators/metabolism , Intercellular Adhesion Molecule-1/metabolism , Lipoproteins, LDL , Male , Matrix Metalloproteinase 2/metabolism , Membrane Proteins/metabolism , Mice , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/metabolism , Myocytes, Smooth Muscle/drug effects , NF-E2-Related Factor 2/metabolism , NF-kappa B/metabolism , Plaque, Atherosclerotic/metabolism , Plaque, Atherosclerotic/pathology , Rats , Signal Transduction , Triglycerides/bloodABSTRACT
Vascular smooth muscle cells (VSMCs) lesions play an important role in atherosclerosis. The latest findings indicate that green tea extract has potential benefits for patients with atherosclerosis, but the components and mechanisms of action are unknown. (-)-Epicatechin gallate (ECG) is the main active ingredient extracted from green tea and has significant biological functions. However, the mechanism of ECG in atherosclerosis remains unclear. Therefore, we investigated the intervention of ECG on VSMCs induced by oxidized low-density lipoprotein (ox-LDL). The results show that ECG reduces the inflammatory response by preventing the overproduction of inflammatory mediators in VSMCs. ECG regulates the cell cycle and down-regulates the expression of proliferating cell nuclear antigen (PCNA) and cyclinD1, and then exerts an anti-proliferative effect. Furthermore, inhibition of the expression of matrix metalloproteinase 2 (MMP-2) and intercellular adhesion molecule 1 (ICAM-1) may be the mechanism by which ECG inhibits the migration of ox-LDL-induced VSMCs. Oil red O staining results show that ECG can improve cell foaming and reduce the content of total cholesterol (TC). In addition, ECG significantly reduces reactive oxygen species activity and also reduces the expression of p-p38, p-JNK, p-ERK1/2, p-IκBα, p-NF-κBp65, and TLR4. These results indicate that ECG has potential clinical applications for preventing atherosclerosis.
Subject(s)
Atherosclerosis/drug therapy , Catechin/analogs & derivatives , Cell Movement/drug effects , Cell Proliferation/drug effects , Muscle, Smooth, Vascular/drug effects , Myocytes, Smooth Muscle/drug effects , Animals , Atherosclerosis/metabolism , Atherosclerosis/pathology , Catechin/pharmacology , Cells, Cultured , Foam Cells/drug effects , Foam Cells/metabolism , Foam Cells/pathology , Inflammation Mediators/metabolism , Intercellular Adhesion Molecule-1/metabolism , Lipoproteins, LDL/pharmacology , Matrix Metalloproteinase 2/metabolism , Mitogen-Activated Protein Kinases/metabolism , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/pathology , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Phosphorylation , Plaque, Atherosclerotic , Rats , Reactive Oxygen Species/metabolism , Signal TransductionABSTRACT
BACKGROUND: Huperzine A (HupA) is a selective acetylcholinesterase inhibitor used to treat Alzheimer's disease. The existing dosage of HupA lacks brain selectivity and can cause serious side effects in the gastrointestinal and peripheral cholinergic systems. PURPOSE: The aim of this study was to develop and characterize a HupA nanoemulsion (NE) and a targeted HupA-NE modified with lactoferrin (Lf) for intranasal administration. METHODS: The NE was formulated using pseudo-ternary phase diagrams and optimized with response surface methodology. Particle size distribution and zeta potential were evaluated, and transmission electron microscopy was performed. We investigated the transport mechanisms of HupA-NEs into hCMEC/D3 cells, an in vitro model of the blood-brain barrier. HupA-NE, Lf-HupA-NE, and HupA solution were intranasally administered to rats to investigate the brain-targeting effects of these formulations. A drug targeting index (DTI) was calculated to determine brain-targeting efficiency. RESULTS: Optimized HupA-NE had a particle size of 15.24±0.67 nm, polydispersity index (PDI) of 0.128±0.025, and zeta potential of -4.48±0.97 mV. The composition of the optimized HupA-NE was 3.00% isopropyl myristate (IPM), 3.81% Capryol 90, and 40% Cremophor EL + Labrasol. NEs, particularly Lf-HupA-NE, were taken up into hCMEC/D3 cells to a greater extent than pure drug alone. Western blot analysis showed that hCMEC/D3 cells contained P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), and multidrug resistance associated protein 1 (MRP1) transporters. The likely mechanisms resulting in higher NE transport to the brain were uptake by specific transporters and transcytosis. In vivo, intranasal Lf-HupA-NE significantly enhanced drug delivery to the brain compared to HupA-NE, which was confirmed by differences in pharmacokinetic parameters. The DTI of Lf-HupA-NE (3.2±0.75) demonstrated brain targeting, and the area under the curve for Lf-HupA-NE was significantly higher than that for HupA-NE. CONCLUSION: Lf-HupA-NE is a promising nasal drug delivery carrier for facilitating delivery of HupA to the central nervous system.