Gastroprotective Effects of Periplaneta americana L. Extract Against Ethanol-Induced Gastric Ulcer in Mice by Suppressing Apoptosis-Related Pathways

Although Periplaneta americana L. and its modern preparation, Kangfuxin liquid, have been extensively applied for ulcerative diseases in gastrointestinal tract (e.g., gastric ulcer (GU) and ulcerative colitis, the effective components and potential mechanisms) remain unclear. In accordance with the accumulating research evidences, the relieving/exacerbating of GU is noticeably correlated to focal tissue programmed cell death. Herein, gastro-protective effects of the effective Periplaneta americana L. extract (PAE) fraction were assessed in vitro and in vivo, involving in programmed cell death-related signaling channels. To screen the effective PAE fraction exerting gastroprotective effects, several PAE fractions were gained based on a wide range of ethanol solution concentration, and they were assessed on ethanol-induced ulcer mice. Based on HPLC investigation with the use of nucleosides, the chemical composition of screened effective PAE, extracted by 20% ethanol, was analyzed in terms of quality control. Based on CCK-8 assay, the protective effects on GES-1 cells, impaired by ethanol, of PAE were assessed. After 3 days pre-treatment with PAE (200, 400, 800 mg/kg), the gastric lesions were assessed by tissue morphology, and periodic acid-schiff (PAS) staining, as well as hematoxylin and eosin (H&E) based histopathology-related investigation. The levels for inflammation cytokines (IL1-β, TNF-α, IL-18, PGE2, and IL-6), antioxidant indices (SOD and MDA) were examined via ELISA. In the meantime, based on Western Blotting assay, the expression levels of some programmed cell death-related protein targets (NLRP3, caspase-1, NF-κB p65, MyD88, and TLR4) were analyzed. As revealed from the results, PAE is capable of alleviating gastric mucosa impairment, suppressing the inflammatory cytokines, and down-regulating the MyD88/NF-κB channels. Accordingly, 20% ethanol extract of Periplaneta americana L. would contribute its gastroprotective effects, thereby providing the evidence that its anti-GU mechanisms correlated with inhibiting programmed cell death channel.

The Supportive Role of NSC328382, a P2X7R Antagonist, in Enhancing the Inhibitory Effect of CRID3 on NLRP3 Inflammasome Activation in Rats with Dextran Sodium Sulfate-Induced Colitis

Purpose

The NLRP3 inflammasome is a substantial component of the inflammation process. The complex pathogenesis of and the implication of a vast number of components in the inflammasome-activation pathway prompted us to search for compounds that have a wide therapeutic index and act at the level of multiple cellular targets. Although CRID3 blocks NLRP3 with high specificity in the laboratory, clinical trials of the compound reported weaker potency.

Methods

We used NSC328382, a P2X7R antagonist, as an adjunctive therapy and generated a strategy to potentiate the effects of CRID3 in rats with DSS-induced colitis.

Results

NSC328382/CRID3 combined therapy exhibited a significantly increased efficacy compared with either of the monotherapies. NSC328382/CRID3 was more efficient in 1) attenuating colon shortening and disease activity; 2) improving goblet cell density and both the macroscopic and microscopic scenario of the injured colon; 3) improving the antioxidant defense mechanisms of the inflamed colon against oxidative stress; and 4) mitigating the inflammation state by downregulating the proinflammatory cytokines. Pyroptotic cell death was also conspicuously restrained. Additionally, NSC328382 interrupted the MyD88/NF-κB axis. Moreover, NSC328382/CRID3 exhibited the ability to alter Th1/Th2 dominance.

Conclusion

The clinical application of NSC328382/CRID3 may result in the generation of a novel approach for the treatment of IBDs.

BBG enhances OLT1177-induced NLRP3 inflammasome inactivation by targeting P2X7R/NLRP3 and MyD88/NF-κB signaling in DSS-induced colitis in rats

Chronic ulceration of the colon is associated with the activation of TLR4/NF-κB and P2X7R/NLRP3 signaling pathways. We investigated the effect of individual or combined administration of BBG, a P2X7R blocker, and OLT1177, a selective NLRP3 inhibitor, in the dextran sodium sulfate-induced ulcerative colitis (UC) rat model. The ulcerative rats were treated orally with brilliant blue G (BBG) (50 mg/kg/day) or OLT1177 (200 mg/kg/day) or a combination of both. Myd88 and NF-κB levels were measured by ELISA, qRT-PCR, and immunohistochemical staining. Cytokines known to be associated with TLR4/NF-κB or P2X7R/NLRP3 signaling were measured by ELISA. P2X7R and NLRP3 expression were measured by ELISA and qRT-PCR. The administration of BBG or OLT1177 ameliorated the toxic effects of DSS on the colon as they restored normal colonic macroscopic and microscopic morphology. BBG administration, but not OLT1177, reduced the expression of Myd88, NF-κB, IL-6, and TNF-α in addition to lowering P2X7R and oxidative stress levels. Individual BBG or OLT1177 administration decreased NLRP3 inflammasome recruitment and subsequent activation of caspase-1, IL-1β, and IL-18. However, the combined administration of OLT1177 with BBG potentiated its inhibitory effect on the NLRP3, which was reflected by the additional suppressive effect on caspase-1, IL-1β, IL-18 levels. In conclusion, BBG/OLT1177 exhibited complementary effects and effectively ameliorated UC. This novel approach provides a basis for the clinical application of this combination for the treatment of IBDs and might also be promising for the pharmacological intervention of other NLRP3 inflammasome-dependent inflammatory conditions.

Long non-coding RNA activated by transforming growth factor beta alleviates lipopolysaccharide-induced inflammatory injury via regulating microRNA-223 in ATDC5 cells

Osteoarthritis (OA) is a conversant joint disease, which seriously threatens the health of the elderly, and even leads to disability. Long non-coding RNA-activated by transforming growth factor beta (lncRNA-ATB) has been reported in diverse cancers. However, the functions of lncRNA-ATB in OA remain uninvestigated. The current study aimed to explore the impacts of lncRNA-ATB on lipopolysaccharide (LPS)-induced inflammatory injury in ATDC5 cells and to uncover the underlying mechanism. LPS-induced ATDC5 cell injury model was constructed, and the effects of lncRNA-ATB on LPS-injured cells were explored via analyzing cell viability, apoptosis, iNOS, COX-2, and inflammatory cytokines (IL-6 and TNF-α). Subsequently, the relationship between lncRNA-ATB and microRNA (miR)-223 was detected, and whether miR-223 was involved in modulating LPS-induced cells injury in ATDC5 cells was investigated. Finally, MyD88/NF-κB and p38MAPK pathways were assessed to explore the underlying mechanism. Results showed that LPS repressed cell viability, induced apoptosis, and promoted iNOS, COX-2, IL-6 and TNF-α expression. Additionally, we observed that lncRNA-ATB expression was down-regulated in LPS-injured cells, and lncRNA-ATB overexpression significantly alleviated LPS-induced inflammatory injury in ATDC5 cells. Interesting results revealed that miR-223 expression was down-regulated by lncRNA-ATB and miR-223 overexpression declined the protective effect of lncRNA-ATB on LPS-injured ATDC5 cells. Further, the signaling pathway experiments showed that lncRNA-ATB inhibited MyD88/NF-κB and p38MAPK pathways by down-regulating miR-223 in LPS-injured cells. These data demonstrated that lncRNA-ATB protected ATDC5 cells against LPS-induced inflammatory injury by repressing MyD88/NF-κB and p38MAPK pathways, which was mediated by down-regulation of miR-223.