Da Chengqitang Protects Intestinal Barrier in Septic Mice via Endogenous Antimicrobial Peptide mCRAMP / 中国实验方剂学杂志

ObjectiveMolecular docking and animal experiments were employed to explore the protective effect and mechanism of Da Chengqitang （DCQD） on intestinal barrier in septic mice. MethodText mining method was used to screen the active ingredients in DCQD. AutoDock Tools and Discovery Studio were used to study the interactions of active components with the core target proteins ［claudin-1， tumor necrosis factor （TNF）-α， interleukin （IL）-6， endogenous antimicrobial peptide mCRAMP， Toll-like receptor 4 （TLR4）， and myeloid differentiation primary response gene 88 （MyD88）］ in sepsis. Fifty C57BL/6 mice were randomized into sham， model， low- and high-dose （4 g∙kg-1 and 8 g∙kg-1） DCQD， and ulinastatin groups （n=10）. Before， during， and after the day of modeling surgery， each group was administrated with corresponding drugs. The mice in other groups except the model group were subjected to modeling by cecal ligation and puncture. Enzyme-linked immunosorbent assay （ELISA） was used measure the serum level of D-lactic acid to assess intestinal mucosa permeability. Hematoxylin-eosin staining was employed to observe the histopathological changes in the ileum and assess the intestinal mucosal damage and inflammatory infiltration. Western blotting was employed to determine the expression levels of tight junction proteins claudin-1 and occludin in the ileal tissue， which were indicative of the bowel barrier function. The TNF-α and IL-6 levels were measured by ELISA to assess the intestinal inflammation. The expression of mCRAMP in the ileal tissue was observed by immunohistochemistry. The mRNA levels of mCRAMP， TLR4， and MyD88 in mouse ileal tissue were determined by Real-time polymerase chain reaction， on the basis of which the mechanism of DCQD in protecting the intestinal barrier of septic mice was explored. ResultMolecular docking results showed that most of the 10 active ingredients of DCQD that were screened out by text mining could bind to sepsis targets by van der Waals force， hydrogen bonding， and other conjugated systems. The results of animal experiments showed that compared with the model group， low- or high-dose DCQD lowered the D-lactic acid level in the serum （P<0.01）， alleviated damage to the ileal tissue and mucosal edema， protected the small intestine villus integrity， reduced inflammatory cell infiltration， promoted the expression of claudin-1 （P<0.01）， lowered the IL-6 level （P<0.01）， up-regulated the mRNA and protein levels of mCRAMP （P<0.01）， and down-regulated the mRNA and protein levels of TLR4 and MyD88 （P<0.01） in the ileal tissue. In addition， high-dose DCQD lowered the TNF-α level and promoted the expression of occludin in the ileum tissue （P<0.01）， and low-dose DCQD up-regulated the protein level of occludin in the ileum tissue （P<0.05）. ConclusionDCQD has a protective effect on intestinal barrier in septic mice. It can reduce intestinal inflammation， repair intestinal mucosal damage， improve the tight junction protein level， and reduce intestinal mucosal permeability by up-regulating the mRNA and protein levels of mCRAMP and the down-regulating the expression of genes in the TLR4/MyD88 pathway.

Research on the anti-tumor effect of nordihydroguaiaretic acid targeting MyD88 / 药学学报

This study mainly explores the role of myeloid differentiation primary response protein 88 (MyD88) in tumorigenesis and development, to identify active compounds targeting MyD88. CRISPR/Cas9 system and xenograft tumor model were used to detect the effect of MyD88 deletion on tumor growth, and the experimental animal ethics review number was PZSHUTCM200828006. Microscale thermophoresis technology (MST) was used to identify compounds directly bind to MyD88 and further detect the impact of candidate small molecules on cell proliferation. Results showed that depletion of MyD88 significantly inhibited xenograft tumor growth of colon cancer, pancreatic cancer and skin cancer and the activity of NF-κB signaling pathway. MST showed that nordihydroguaiaretic acid (NDGA) bound to MyD88, with the binding dissociation constant Kd of 14.61 µmol·L-1. NDGA inhibited NF-κB reporting system activation and phosphorylation of p65, the key factor in NF-κB signal pathway. In addition, the results of colony formation assay showed that NDGA suppressed the proliferation of tumor cells. The above results show that, MyD88 is a potential therapeutic target for colon cancer, pancreatic cancer and skin cancer, NDGA directly binds to MyD88 and inhibits the activity of NF-κB signaling pathway, as well as inhibits the proliferation of pancreatic cancer, skin cancer and colon cancer cells.

TLR4-mediated activation of MyD88 signaling induces protective immune response and IL-10 down-regulation in Leishmania donovani infection.

In visceral leishmaniasis, a fragmentary IL-12 driven type 1 immune response along with the expansion of IL-10 producing T-cells correlates with parasite burden and pathogenesis. Successful immunotherapy involves both suppression of IL-10 production and enhancement of IL-12 and nitric oxide (NO) production. As custodians of the innate immunity, the toll-like receptors (TLRs) constitute the first line of defense against invading pathogens. The TLR-signaling cascade initiated following innate recognition of microbes shapes the adaptive immune response. Whereas numerous studies have correlated parasite control to the adaptive response in Leishmania infection, growing body of evidence suggests that the activation of the innate immune response also plays a pivotal role in disease pathogenicity. In this study, using a TLR4 agonist, a Leishmania donovani (LD) derived 29 kDa β 1,4 galactose terminal glycoprotein (GP29), we demonstrated that the TLR adaptor myeloid differentiation primary response protein-88 (MyD88) was essential for optimal immunity following LD infection. Treatment of LD-infected cells with GP29 stimulated the production of IL-12 and NO while suppressing IL-10 production. Treatment of LD-infected cells with GP29 also induced the degradation of IKB and the nuclear translocation of NF-kB, as well as rapid phosphorylation of p38 MAPK and p54/56 JNK. Knockdown of TLR4 or MYD88 using siRNA showed reduced inflammatory response to GP29 in LD-infected cells. Biochemical inhibition of p38 MAPK, JNK or NF-kB, but not p42/44 ERK, reduced GP29-induced IL-12 and NO production in LD-infected cells. These results suggested a potential role for the TLR4-MyD88–IL-12 pathway to induce adaptive immune responses to LD infection that culminated in an effective control of intracellular parasite replication.

Dinamica de resuuesta inmune primaria y secundaria: modelo: anticuerpos anti hbs / Dynamics of the immune primary and secondary response: Model, antibodies HBS

Se estudió la cinética individual y colectiva de la dinámica de la respuesta inmune y sus categorías, utilizando como modelo la respuesta de anticuerpos contra el antígeno de superficie del virus productor de la hepatitis B. En estudiantes de Medicina latinoamericanos, de 20 años promedio, se cuantificó la permanencia de niveles de anticuerpos después de 3 años de un esquema completo de inmunización y se encontraron valores promedio de 168 UI/L, un incremento de 757 UI/L en 15 días post refuerzo, lo que permitió estudiar el índice de memoria / durabilidad que fue 5,5 y conocer el incremento en UI/L por día y por microgramo de antígeno: 29 UI/ µg de antígeno. Se estimó, a partir de los valores de durabilidad a los 3 años de vacunados, la intensidad de la respuesta post esquema, que fue 336UI/L; igualmente a partir de los valores alcanzados al analizar memoria, 925 UI/L, pronosticamos una seroprotección hasta 18 años más, es decir, hasta el 2023. Obtuvimos resultados preliminares de utilización del modelo cinético para estudio de inmunoeficiencia.

It was studied the individual and collective kinetics of the dynamics of the immune response and their categories using like a model the response of antibodies against the antigen of surface of the virus producing of the hepatitis B. In students of Medicine 20 years old average, a permanency of antibodies of 168 UI/L was observed, after 3 years of a complete outline of immunization, an increment of 757 UI/L in 14 days post booster, what allowed to study the index by memory / durability that was 5.5 and to know the increment in UI/L per day (54 UI/day) and for antigen micro-gramme: 37.8 UI/µg. It was considered, starting from permanency of antibodies to the 3 years of vaccination, the intensity of the response post schedule that was 336UI/L, equally starting from the values reached in the memory, 925 UI/L, we prognosis a seroprotection up to 18 years or more, that is to say up to the 2023. We obtained preliminary results of use of the kinetic pattern for immune-efficiency study.