scholarly journals Development of a Highly Efficient Hybrid Peptide That Increases Immunomodulatory Activity Via the TLR4-Mediated Nuclear Factor-κB Signaling Pathway

2019 ◽  
Vol 20 (24) ◽  
pp. 6161
Author(s):  
Lulu Zhang ◽  
Xubiao Wei ◽  
Rijun Zhang ◽  
Matthew Koci ◽  
Dayong Si ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Immunosuppressive Agents ◽  
Immunomodulatory Activity ◽  
Hybrid Peptide ◽  
T Lymphocyte Subsets ◽  
Necrosis Factor Alpha ◽  
Hybrid Peptides ◽  
Macrophage Phagocytosis ◽  
Native Peptides

Immunity is a defensive response that fights disease by identifying and destroying harmful substances or microbiological toxins. Several factors, including work-related stress, pollution, and immunosuppressive agents, contribute to low immunity and poor health. Native peptides, a new class of immunoregulatory agents, have the potential for treating immunodeficiencies, malignancies, and infections. However, the potential cytotoxicity and low immunoregulatory activity and stability of native peptides have prevented their development. Therefore, we designed three hybrid peptides (LTAa, LTAb, and LTAc) by combining a characteristic fragment of LL-37 with an active Tα1 center that included Tα1 (17–24), Tα1 (20–25), and Tα1 (20–27). The best hybrid peptide (LTAa), according to molecule docking and in vitro experiments, had improved immunoregulatory activity and stability with minimal cytotoxicity. We investigated the immunoregulatory effects and mechanisms of LTAa using a cyclophosphamide-immunosuppressed murine model. LTAa effectively reversed immunosuppression by enhancing immune organ development, activating peritoneal macrophage phagocytosis, regulating T lymphocyte subsets, and increasing cytokine (tumor necrosis factor-alpha, interleukin-6, and interleukin-1β) and immunoglobulin (IgA, IgG, and IgM) contents. The immunomodulatory effects of LTAa may be associated with binding to the TLR4/MD-2 complex and activation of the NF-κB signaling pathway. Therefore, LTAa could be an effective therapeutic agent for improving immune function.

scholarly journals Design and Immunological Evaluation of a Hybrid Peptide as a Potent TLR2 Agonist by Structure-Based Virtual Screening

2021 ◽  
Vol 9 ◽  
Author(s):  
Lulu Zhang ◽  
Xubiao Wei ◽  
Rijun Zhang ◽  
Paul E. Mozdziak ◽  
Dayong Si ◽  
...  
Keyword(s):  
Immune System ◽  
Organ Injury ◽  
Immunomodulatory Activity ◽  
Immunomodulatory Effects ◽  
T Lymphocyte Subsets ◽  
Immunomodulatory Agents ◽  
Tlr2 Agonist ◽  
Hybrid Peptides ◽  
Long Time

Immunity is a versatile defensive response that is involved in protecting against disease by identifying and destroying self and non-self harmful substances. As a state of temporary or permanent immune dysfunction, immunosuppression can make an organism more susceptible to infection, organ injury, and cancer due to damage to the immune system. It has taken a long time to develop new immunomodulatory agents to prevent and treat immunosuppressive diseases. In recent years, Toll-like receptor 2 (TLR2) agonists have been reported to have profound effects on the immune system, and they are regarded as potent immunomodulatory candidates. TP5 and LL-37, the potent immunomodulatory agents, have been reported to produce a robust innate immune response by binding to TLR2. However, their development has been weakened by several concerns, such as potential cytotoxicity, weak physiological stability and poor immunomodulatory activity. To overcome these challenges, hybridization has been proposed. Therefore, six hybrid peptides (LTPa, LTPb, LTPc, TPLa, TPLb, and TPLc) were designed by combining the full-length TP5 with a characteristic fragment of LL-37 that included LL-37 (13–36), LL-37 (17–29), and LL-37 (13–31). LTPa, the most potent TLR2 agonist, was simply and effectively screened by molecular docking and in vitro experiments. Furthermore, the immunomodulatory effects of LTPa were confirmed by a CTX-immunosuppressed murine model, which demonstrated that LTPa successfully inhibit immunosuppression, increased immune organ indices, enhanced DC maturation, regulated T lymphocyte subsets, and increased cytokine and Ig contents. Our study also revealed that the immunomodulatory effects of LTPa are associated with binding to TLR2, forming TLR2 clusters, and activating the NF-κB signaling pathway.

scholarly journals Targeting the TLR2 Receptor With a Novel Thymopentin-Derived Peptide Modulates Immune Responses

2021 ◽  
Vol 12 ◽  
Author(s):  
Xubiao Wei ◽  
Lulu Zhang ◽  
Rijun Zhang ◽  
Rujuan Wu ◽  
James N. Petitte ◽  
...  
Keyword(s):  
Immune Responses ◽  
Half Life ◽  
In Silico Analysis ◽  
Binding Activity ◽  
Organ Injury ◽  
Immunomodulatory Activity ◽  
T Lymphocyte Subsets ◽  
Hybrid Peptides ◽  
Functional Peptides

The innate and adaptive immune systems act in concert to protect us from infectious agents and other harmful substances. As a state of temporary or permanent immune dysfunction, immunosuppression can make an organism more susceptible to infection, organ injury, and cancer due to damage to the immune system. It takes a long time to develop new immunomodulatory agents to prevent and treat immunosuppressive diseases, with slow progress. Toll-like receptor 2 (TLR2) agonists have been reported as potential immunomodulatory candidates due to their effective activation of immune responses. It has been demonstrated that thymopentin (TP5) could modulate immunity by binding to the TLR2 receptor. However, the fairly short half-life of TP5 greatly reduces its pharmacological potential for immunosuppression therapy. Although peptide cathelicidin 2 (CATH2) has a long half-life, it shows poor immunomodulatory activity and severe cytotoxicity, which seriously hampers its clinical development. Peptide hybridization is an effective approach for the design and engineering of novel functional peptides because hybrid peptides combine the advantages and benefits of various native peptides. In this study, to overcome all these challenges faced by the parental peptides, six hybrid peptides (CaTP, CbTP, CcTP, TPCa, TPCb, and TPCc) were designed by combining the full-length TP5 with different active fragments of CATH2. CbTP, the most potent TLR2 agonist among the six hybrid peptides, was effectively screened through in silico analysis and in vitro experiments. The CbTP peptide exhibited lower cytotoxicity than either CATH2 or TP5. Furthermore, the immunomodulatory effects of CbTP were confirmed in a CTX-immunosuppressed mouse model, which showed that CbTP has increased immunopotentiating activity and physiological stability compared to the parental peptides. CbTP successfully inhibited immunosuppression and weight loss, increased immune organ indices, and improved CD4+/CD8+ T lymphocyte subsets. In addition, CbTP significantly increased the production of the cytokine TNF-α and IL-6, and the immunoglobulins IgA, IgM, and IgG. The immunoenhancing effects of CbTP were attributed to its TLR2-binding activity, promoting the formation of the TLR2 cluster, the activation of the TLR2 receptor, and thus activation of the downstream MyD88-NF-кB signaling pathway.

scholarly journals Artemisinin Ameliorates Osteoarthritis by Inhibiting the Wnt/β-Catenin Signaling Pathway

2018 ◽  
Vol 51 (6) ◽  
pp. 2575-2590 ◽  
Author(s):  
Gang Zhong ◽  
Ruiming Liang ◽  
Jun Yao ◽  
Jia Li ◽  
Tongmeng Jiang ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Cruciate Ligament ◽  
Interleukin 1 ◽  
Cartilage Degradation ◽  
Chondrocyte Apoptosis ◽  
Enzyme Linked Immunosorbent Assay ◽  
Cell Viability Assay ◽  
Necrosis Factor Alpha ◽  
Anti Inflammatory

Background/Aims: Current drug therapies for osteoarthritis (OA) are not practical because of the cytotoxicity and severe side-effects associated with most of them. Artemisinin (ART), an antimalarial agent, is well known for its safety and selectivity to kill injured cells. Based on its anti-inflammatory activity and role in the inhibition of OA-associated Wnt/β-catenin signaling pathway, which is crucial in the pathogenesis of OA, we hypothesized that ART might have an effect on OA. Methods: The chondro-protective and antiarthritic effects of ART on interleukin-1-beta (IL-1β)-induced and OA patient-derived chondrocytes were investigated in vitro using cell viability assay, glycosaminoglycan secretion, immunofluorescence, quantitative reverse transcription-polymerase chain reaction, and western blotting. We also used OA model rats constructed by anterior cruciate ligament transection and medial meniscus resection (ACLT+MMx) in the joints to investigate the effects of ART on OA by gross observation, morphological staining, immunohistochemistry, and enzyme-linked immunosorbent assay. Results: ART exhibited potent anti-inflammatory effects by inhibiting the expression of proinflammatory chemokines and cytokines, including interleukin (IL)-1β, IL-6, tumor necrosis factor alpha, and matrix metallopeptidase-13. It also showed favorable chondro-protective effect as evidenced by enhanced cell proliferation and viability, increased glycosaminoglycan deposition, prevention of chondrocyte apoptosis, and degeneration of cartilage. Further, ART inhibited OA progression and cartilage degradation via the Wnt/β-catenin signaling pathway, suggesting that it might serve as a Wnt/β-catenin antagonist to reduce inflammation and prevent cartilage degradation. Conclusion: In conclusion, ART alleviates IL-1β-mediated inflammatory response and OA progression by regulating the Wnt/β-catenin signaling pathway. Thereby, it might be developed as a potential therapeutic agent for OA.

scholarly journals Mechanism of KLF4 Protection against Acute Liver Injury via Inhibition of Apelin Signaling

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Weitao Ji ◽  
Hongyun Shi ◽  
Hailin Shen ◽  
Jing Kong ◽  
Jiayi Song ◽  
...  
Keyword(s):  
Liver Injury ◽  
Signaling Pathway ◽  
Acute Liver Injury ◽  
Control Group ◽  
Necrosis Factor Alpha ◽  
Protein Levels ◽  
Klf4 Expression ◽  
Mrna And Protein Expression

Krüppel-like factor 4 (KLF4) is a key transcription factor that regulates genes involved in the proliferation or differentiation in different tissues. Apelin plays roles in cardiovascular functions, metabolic disease, and homeostatic disorder. However, the biological function of apelin in liver disease is still ongoing. In this study, we investigated the mechanism of KLF4-mediated protection against acute liver injury via the inhibition of the apelin signaling pathway. Mice were intraperitoneally injected with carbon tetrachloride (CCl4; 0.2 mL dissolved in 100 mL olive oil, 10 mL/kg) to establish an acute liver injury model. A KLF4 expression plasmid was injected through the tail vein 48 h before CCl4 treatment. In cultured LX-2 cells, pAd-KLF4 or siRNA KLF4 was overexpressed or knockdown, and the mRNA and protein levels of apelin were determined. The results showed that the apelin serum level in the CCl4-injected group was higher than that of control group, and the expression of apelin in the liver tissues was elevated while KLF4 expression was decreased in the CCl4-injected group compared to the KLF4-plasmid-injected group. HE staining revealed serious hepatocellular steatosis in the CCl4-injected mice, and KLF4 alleviated this steatosis in the mice injected with KLF4 plasmid. In vitro experiments showed that tumor necrosis factor-alpha (TNF-α) could downregulate the transcription and translation levels of apelin in LX-2 cells and also upregulate KLF4 mRNA and protein expression. RT-PCR and Western blotting showed that the overexpression of KLF4 markedly decreased basal apelin expression, but knockdown of KLF4 restored apelin expression in TNF-α-treated LX-2 cells. These in vivo and in vitro experiments suggest that KLF4 plays a key role in inhibiting hepatocellular steatosis in acute liver injury, and that its mechanism might be the inhibition of the apelin signaling pathway.

scholarly journals A Novel Peptide Ameliorates LPS-Induced Intestinal Inflammation and Mucosal Barrier Damage via Its Antioxidant and Antiendotoxin Effects

2019 ◽  
Vol 20 (16) ◽  
pp. 3974 ◽  
Author(s):  
Lulu Zhang ◽  
Xubiao Wei ◽  
Rijun Zhang ◽  
Dayong Si ◽  
James N. Petitte ◽  
...  
Keyword(s):  
Half Life ◽  
Intestinal Inflammation ◽  
Mucosal Barrier ◽  
Hybrid Peptide ◽  
Active Centre ◽  
Necrosis Factor Alpha ◽  
New Class ◽  
Factor Alpha ◽  
Anti Inflammatory

Intestinal inflammation is an inflammatory disease resulting from immune dysregulation in the gut. It can increase the risk of enteric cancer, which is a common malignancy globally. As a new class of anti-inflammatory agents, native peptides have potential for use in the treatment of several intestinal inflammation conditions; however, their potential cytotoxicity and poor anti-inflammatory activity and stability have prevented their development. Hybridization has been proposed to overcome this problem. Thus, in this study, we designed a hybrid peptide (LL-37-TP5, LTP) by combing the active centre of LL-37 (13–36) with TP5. The half-life and cytotoxicity were tested in vitro, and the hybrid peptide showed a longer half-life and lower cytotoxicity than its parental peptides. We also detected the anti-inflammatory effects and mechanisms of LTP on Lipopolysaccharide (LPS)-induced intestinal inflammation in murine model. The results showed that LTP effectively prevented LPS-induced weight loss, impairment of intestinal tissues, leukocyte infiltration, and histological evidence of inflammation. Additionally, LTP decreased the levels of tumour necrosis factor-alpha, interferon-gamma, and interleukin-6; increased the expression of zonula occludens-1 and occludin; and reduced permeability in the jejunum of LPS-treated mice. Notably, LTP appeared to be more potent than the parental peptides LL-37 and TP5. The anti-inflammatory effects of LTP may be associated with the neutralization of LPS, inhibition of oxidative stress, and inhibition of the NF-κB signalling pathway. The findings of this study suggest that LTP might be an effective therapeutic agent for treating intestinal inflammation.

scholarly journals Immunostimulants in respiratory diseases: focus on Pidotimod

2019 ◽  
Vol 14 ◽  
Author(s):  
Francesca Puggioni ◽  
Magna Alves-Correia ◽  
Manar-Farouk Mohamed ◽  
Niccolò Stomeo ◽  
Riccardo Mager ◽  
...  
Keyword(s):  
T Lymphocyte ◽  
Respiratory Diseases ◽  
Dendritic Cell Maturation ◽  
Immunomodulatory Activity ◽  
T Lymphocyte Subsets ◽  
T Lymphocyte Proliferation ◽  
Hla Dr ◽  
Airway Infections ◽  
Tract Infections

Usefulness of Pidotimod and its role as immunostimulant, has been discussed, we know, for several decades. Nevertheless, there is still much to know. Understanding its mechanisms and its potential usefulness in airway infections and its prevention, asthma both Th2 and non Th2 type, bronchiectasis, as adjuvant in vaccination and in allergen immunotherapy still remains to clearly unveil. The aim of this paper was to provide a useful updated review of the role of the main available immunostimulants, giving particular focus on Pidotimod use and its potentials utility in respiratory diseases. Pidotimod showed its usefulness in reducing need for antibiotics in airway infections, increasing the level of immunoglobulins (IgA, IgM, IgG) and T-lymphocyte subsets (CD3+, CD4+) endowed with immunomodulatory activity that affect both innate and adaptive immune responses. Higher expression of TLR2 and of HLA-DR molecules, induction of dendritic cell maturation and release of pro-inflammatory molecules, stimulation of T lymphocyte proliferation and differentiation toward a Th1 phenotype, as well as an increase of the phagocytosis have been demonstrated to be associated with Pidotimod in in vitro studies. All these activities are potentially useful for several respiratory conditions such as asthma, COPD, and recurrent respiratory tract infections.

scholarly journals Dihydromyricetin alleviates endothelial inflammatory response through IRE1α/NF-κB signaling pathway in sepsis

2021 ◽  
Author(s):  
Xifeng Wang ◽  
Xiaomin Xu ◽  
Yu peng Yang ◽  
Xin Xin ◽  
Zekang Li ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Endoplasmic Reticulum ◽  
Inflammatory Response ◽  
Er Stress ◽  
Signaling Pathway ◽  
Umbilical Vein ◽  
Cecal Ligation ◽  
Protective Effects ◽  
Necrosis Factor Alpha

IntroductionThe high mortality of sepsis is closely related to disorder of coagulation induced by endothelial inflammatory response. Our aim is to investigate the protective effects of Dihydromyricetin (DHM) on endothelial cells in sepsis and the endoplasmic reticulum (ER) stress mechanism.Material and methodsIn vivo, we conducted an animal study for which fifty male Wistar rats were randomly and equally divided into five groups: sham group, cecal ligation and puncture (CLP) group and three CLP+ DHM (50, 100, 150 mg/kg) groups, the DHM was orally administered 2 h after CLP for 3 days (once per day). In vitro, human umbilical vein endothelial cells (HUVECs) were treated with DHM (50μmol) for 24 h after stimulation by lipopolysaccharide (LPS). In the inhibition groups, reactive oxygen species (ROS) inhibitor N-acetylcysteine (NAC, 3 mmol) and endoplasmic reticulum (ER) stress inhibitor (STF-083010, 10 μmol) were incubated prior to LPS.ResultsOur results indicated that DHM (150 mg/kg) alleviated the histopathological injury of endothelium, decreased the release of inflammatory cytokines and adhesion molecules such as interleukin-1β (IL-1β), interleukin-6 (IL-6) , tumor necrosis factor alpha (TNF-α), vascular cell adhesion molecule 1 (VCAM-1) and endothelin-1 (ET-1), and inhibited the production of ROS production. In addition, we found that DHM ameliorated ER damage, significantly decreased the protein expressions of IRE1α/NF-κB signaling pathway.ConclusionsDHM treatment alleviated inflammatory response of endothelial cells in sepsis through the IRE1α/NF-κB signaling pathway triggered by oxidative stress. This study provided experimental rationale for the treatment of DHM on therapy of sepsis.

scholarly journals UJI AKTIVITAS FAGOSITOSIS MAKROFAG EKSTRAK ETANOL DAUN SUJI (Dracaena angustifolia (Medik.)Roxb. ) SECARA IN VITRO

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Nestri Handayani
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Ethanolic Extract ◽  
Ethanol Extract ◽  
Immunomodulatory Activity ◽  
Macrophage Activity ◽  
Macrophage Phagocytosis ◽  
Phagocytosis Index ◽  
Layer Chromatography

UJI AKTIVITAS FAGOSITOSIS  MAKROFAG  EKSTRAK ETANOL  DAUN SUJI (Dracaena angustifolia (Medik.)Roxb. ) SECARA  IN VITRONestri Handayani 1,2*), Subagus Wahyuono2), Triana Hertiani2), Retno Murwanti2)1)Program Studi Farmasi, FMIPA, Universitas Sebelas Maret Surakarta2)Fakultas Farmasi Universitas Gadjah Mada Yogyakarta*Email : [email protected]  ABSTRACT Immunomodulatory activity has been carried out on ethanol extract of suji leaf (Dracaena angustifolia (Medik.) Roxb with in vitro macrofag phagocytosis method. . Suji is a plant that is often used as a food coloring and has long been used medicinally. This study aimed to test in vitro macrophage phagocytosis on ethanol extract of suji leaf. The suji leaves are extracted by maceration method. The obtained viscous extract was then tested for Thin Layer Chromatography (TLC) and in vitro macrophage phagocytosis test. The parameters used are Phagocytosis Index and Macrophage Capacity. The results of in vitro macrophage phagocytosis test with 4 concentrations of 10.25,50 and 100 microgram / ml, showed for the largest average Fagocytosis (IF) Index shown at concentration 10 mcg / ml, while concentrations 25 and 50 mcg / ml showed values The same phagocytic (KF) capacity. Keywords :  Suji leaf, Phagocytic Macrophage Activity,  ethanolic  extract   ABSTRAKUji aktivitas imunomodulator telah dilakukan terhadap ekstrak etanol  daun suji (Dracaena angustifolia (Medik.)Roxb..  Suji merupakan tanaman yang sering digunakan sebagai pewarna makanan dan telah lama digunakan untuk obat. Penelitian ini bertujuan untuk melakukan uji fagositosis makrofag in vitro terhadap ekstrak etanol daun suji. Daun suji diekstraksi dengan metode maserasi. Ekstrak kental yang diperoleh kemudian dilakukan uji Kromatografi Lapis Tipis (KLT) dan uji fagositosis makrofag in vitro. Parameter yang digunakan adalah Indeks fagositosis dan Kapasitas makrofag. Hasil uji fagositosis makrofag in vitro dengan 4 konsentrasi sebesar 10,25,50 dan 100 mikrogram/ml, menunjukkan untuk Indeks Fagositosis (IF) rata-rata terbesar ditunjukkan pada konsentrasi 10 mcg/ml, sedangkan konsentrasi 25 dan 50 mcg/ml menunjukkan nilai  Kapasitas Fagositosis (KF) yang sama besar. Kata kunci : Daun suji, fagositosis makrofag, ekstrak etanol    

scholarly journals Effect of Trovafloxacin on Production of Cytokines by Human Monocytes

1998 ◽  
Vol 42 (7) ◽  
pp. 1713-1717 ◽  
Author(s):  
Anis A. Khan ◽  
Teri R. Slifer ◽  
Jack S. Remington
Keyword(s):  
Inflammatory Responses ◽  
Immunomodulatory Activity ◽  
Human Monocytes ◽  
Healthy Human ◽  
Necrosis Factor Alpha ◽  
In Vitro Synthesis ◽  
Cytokine Synthesis ◽  
Diphenyl Tetrazolium Bromide

ABSTRACT Antibiotics have previously been shown to have immunomodulatory effects. We examined the effect of the broad-spectrum fluoroquinoline antibiotic trovafloxacin on cytokine synthesis by monocytes obtained from healthy human volunteers and stimulated with either lipopolysaccharide or gram-positive cells (heat-killedStaphylococcus aureus [Pansorbin]). Trovafloxacin levels achievable in humans suppressed in vitro synthesis of each of the cytokines analyzed, viz., interleukin-1α (IL-1α), IL-1β, IL-6, IL-10, granulocyte-macrophage colony-stimulating factor, and tumor necrosis factor alpha. This effect was not due to direct effects of the drug on cellular viability; at these concentrations, trovafloxacin did not have demonstrable cytotoxicity for the monocytes, as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. Although similar patterns of suppression of cytokine synthesis were observed in samples obtained from the same volunteers on different days, there were significant day-to-day variations. These results reveal that trovafloxacin possesses significant immunomodulatory activity in vitro and suggest that suppression of acute-phase inflammatory responses may occur in vivo, elicited through trovafloxacin’s effect on cytokine synthesis by human monocytes.

Sign in / Sign up

Export Citation Format

Share Document