Baicalin alleviates TNBS-induced colitis by inhibiting PI3K/AKT pathway activation.

Inflammatory bowel diseases (IBDs) are chronic immunological disorders of the intestinal tract characterized by persistent inflammation. Baicalin, a type of flavonoid, has exhibited a wide range of pharmacological activities, including immunomodulation and anti-inflammation. However, little is known about the therapeutic role of baicalin in IBD. The aim of the present study was to ascertain whether baicalin could be a therapeutic drug of IBD and investigate its specific mechanisms. In the present study, the results revealed that baicalin not only significantly alleviated TNBS-induced colitis by reducing the release of IL-6, TNF-α and IL-1ß and increasing the level of IL-10, but promoted the expression of tight-junction proteins ZO-1 and ß-catenin, which may have been achieved by blockage of the PI3K/AKT signaling pathway. In vitro, the results demonstrated that baicalin clearly inhibited the release of TNF-α, IL-6 and IL-1ß and promoted the expression of IL-10 in LPS-induced HT-29 cells, and significantly decreased LPS-induced HT-29 cell apoptosis by blockage of the PI3K/AKT signaling pathway. In conclusion, the present research revealed for the first time that baicalin acted as a therapeutic drug in IBD by suppression of the PI3K/AKT signaling pathway.

Qing Chang Hua Shi granule ameliorate inflammation in experimental rats and cell model of ulcerative colitis through MEK/ERK signaling pathway.

Ulcerative colitis (UC), a bowel disease with significant morbidity, is associated with inflammation. In this study, the effect of Qingchang Huashi granule (QCHS) on UC and its underlying mechanisms were explored using both animal and cell culture experiments. A rat UC model was induced with trinitro-benzene-sulfonic acid (TNBS), concentrations of the cytokines IL-1α, IL-6, IL-8, IL-1ß, and TNF-α were significantly up-regulated and the concentrations of IL-4, IL-10, and IL-13 were significantly down-regulated compared with the control group (P < 0.05). In contrast, the QCHS and salicylazosulfapyridine (SASP) groups reversed these modulations (P < 0.05). A UC cell model in HT-29 cells was generated using TNF-α combined with lipopolysaccharide treatment. Cells treated with QCHS were used to investigate the possible mechanisms. The expression of apoptosis-related proteins, including Bax/Bcl-2, caspase-3, caspase-9, Fas/Fas-L, and Rafl in the QCHS and SASP groups, were significantly lower than that in the control group in both animal and cell experiments (P < 0.05). In addition, the in vitro results indicate changes in these indicators mediate the MEK/ERK signaling pathways via SGK1. Our results suggested that QCHS could be beneficial in preventing UC progression as an alternative drug for UC treatment.

[Effect of Jianpi Bushen Qingchang Huashi Recipe on Proliferation of Bone Marrow Mesenchymal Stem Cells].

OBJECTIVE: To observe the effect of Jianpi Bushen Qingchang Huashi Recipe (JBQHR) on proliferation and migration of bone marrow mesenchymal stem cells (BMSCs). METHODS: BMSCs were isolated and cultured in vitro with adherence screening method to prepare cell suspension. No drug intervention was given to BMSCs in the vehicle control group. JBQHR at 0.39, 0.78, 1.56 µg/mL was added in BMSCs of low, mid, and high dose JBQHR groups for co-incubation. Its effect on the proliferation of BMSCs was detected by CCK-8. BMSCs migration and chemotactic ability was detected using Transwell method. Each dose JBQHR combined ERK kinase inhibitor U0126 was set up as control. The phosphorylation of extracellular regulated protein kinase (ERK) and CAMP responsive element-binding protein (CREB) were detected by Western blot. RESULTS: Compared with the vehicle control group, the proliferation of BMSCs and BMSCs migration number could be promoted in the 3 JBQHR groups (P < 0.05). Besides, the proliferation of BMSCs was better in mid and high dose JBQHR groups than in the low dose JBQHR group (P < 0.05). Compared with the vehicle control group, the phosphorylation of ERK and CREB could be elevated in the 3 JBQHR groups (P < 0.05), and could be inhibited by U0126 (P < 0.01). Compared with the low dose JBQHR group, the phosphorylation of ERK increased in mid and high dose JBQHR groups with statistical difference (P < 0.05). CONCLUSION: JBQHR could promote the proliferation and migration of BMSCs, and its mechanism might be related to ERK/CREB signaling pathway

[Insulin-like growth factor 1 regulates expression of stem cell factor through ERKMAPK signaling pathway in gastric smooth muscle cell].

OBJECTIVE: To explore the effect and the intracellular signal transduction pathway of insulin-like growth factor 1 (IGF-1) on the expression of stem cell factor (SCF) in gastric smooth muscle cells (SMC). METHODS: Gastric SMC from SD rats were cultured by enzymolysis and identified by α-actin immunofluorescence methods. Western blot and quantitative reverse transcription-polymerase chain reaction were used to examine the expression of SCF in gastric SMC:(1) The level of SCF after gastric SMC were cultured with IGF-1. (2) The level of SCF after IGF-1 receptor (IGF-1Rα) monoclonal antibody were added. (3) Another SMC were pretreated with specific mitogen-activated protein kinase (MEK) inhibitor PD-98059 and phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor LY-294002, and investigate expression of SCF in gastric SMC. RESULTS: A very low level of SCF was expressed in gastric SMC cultured in bovine serum free medium. A low concentration of IGF-1 (5 and 10 µg/L) had no effect on the expression of SCF (both P>0.05), but the expressions of SCF mRNA and protein increased in IGF-1 at a higher concentration (50, 100 and 150 µg/L) (2.79, 5.51 and 5.35-fold in protein respectively, 1.81, 2.54 and 2.38-fold in mRNA respectively, all P<0.05), and IGF-1 in 100 µg/L may be the effective final concentration (all P<0.05). The peak of SCF increment was at the 16th hour with IGF-1 (2.36-fold in protein, 5.51-fold in mRNA, all P<0.05). The expression of SCF could be inhibited by IGF-1 receptor monoclonal antibody in a dose-dependent manner (all P<0.05). The IGF-1-induced SCF expression was reduced significantly by a pretreatment of PD-98059 (23% in protein and 48% in mRNA, P<0.05). And LY-294002 had no effect on the expression of SCF (P>0.05). CONCLUSION: The SCF expression in gastric SMC is stimulated by IGF-1 in both dose- and time-dependent manners through IGF-1R in which ERKMAPK signal transduction may play an important role.

T300A polymorphism of ATG16L1 and susceptibility to inflammatory bowel diseases: a meta-analysis.

AIM: To evaluate the association of the autophagy-related 16-like 1 (ATG16L1) T300A polymorphism (rs2241880) with predisposition to inflammatory bowel diseases (IBD) by means of meta-analysis. METHODS: Publications addressing the relationship between rs2241880/T300A polymorphism of ATG16L1 and Crohn's disease (CD) and ulcerative colitis (UC) were selected from the MEDLINE and EMBASE databases. To make direct comparisons between the data collected in these studies, the individual authors were contacted when necessary to generate a standardized set of data from these studies. From these data, odds ratio (OR) with 95% confidence interval (CI) were calculated. RESULTS: Twenty-five studies of CD were analyzed, 14 of which involved cases of UC. The variant G allele of ATG16L1 was positively associated with CD (OR = 1.32, 95% CI: 1.26-1.39, P < 0.00001) and UC (OR = 1.06, 95% CI: 1.01-1.10, P = 0.02). For child-onset IBD, a higher G allele frequency was found for cases of CD (OR = 1.35, 95% CI: 1.16-1.57, P = 0.0001) than for cases of UC (OR = 0.98, 95% CI: 0.81-1.19, P = 0.84) relative to controls. CONCLUSION: The ATG16L1 T300A polymorphism contributes to susceptibility to CD and UC in adults, but different in children, which implicates a role for autophagy in the pathogenesis of IBD.