Therapeutic Effect and Mechanism of New Maixian Powder on DSS-induced UC Rats

[Objectives] To study the therapeutic effect and mechanism of New Maixian Powder on ulcerative colitis( UC) rats through observing its regulatory effect on the protein kinase R-like endoplasmic reticulum kinase( PERK)/eukaryotic translation initiation factor-2α( e IF-2α)/nuclear transcription factor-kappa B( NF-κB) signaling pathway. [Methods]First,60 SD rats were randomly divided into normal group,model group,mesalazine group,and New Maixian Powder low,medium and high dose groups,10 rats each group. Then,dextran sulfate sodium( DSS) was used to induce UC rats. The mesalazine group was given 0. 42 g/( kg·d) of mesalazine sustained-release granule suspension,New Maixian Powder low,medium and high dose groups were given 1. 5,3,and 6 g/( kg·d) of New Maixian Powder suspension,respectively,and other groups were given an equal volume of physiological saline,continuous intragastric administration for 14 d. Next,the disease activity index( DAI) of UC rats was evaluated; the expression of NF-κB in serum was measured by enzyme-linked immunosorbent assay( ELISA); the expression of PERK and e IF-2α protein and m RNA in colon tissue was detected by Western blot and real-time quantitative polymerase chain reaction( RT q-PCR). [Results] Compared with the normal group,the DAI score and serum NF-κB level in the model group were significantly higher( P < 0. 05),and PERK and e IF-2α protein and m RNA levels in the colon tissue were increased( P < 0. 05); compared with the model group,the DAI score decreased and serum NF-κB level declined in the New Maixian Powder group,and the expression of PERK and e IF-2α protein and m RNA in New Maixian Powder medium dose and high dose groups declined( P < 0. 05). [Conclusions]New Maixian Powder has good therapeutic effect on UC rats,and its mechanism may be connected with the inhibition of the activation of PERK/e IF-2α/NF-κB signaling pathway.

Clinical heterogeneity of NLRP12-associated autoinflammatory diseases

Nod-like receptor family pyrin domain-containing protein 12 (NLRP12) is one of the critical pattern recognition receptors which participates in the regulation of multiple inflammatory responses. Mutations in NLRP12 cause exceptionally rare NLRP12-associated autoinflammatory disease (NLRP12-AID). So far, very few patients with NLRP12-AID have been identified worldwide;therefore, data on the clinical phenotype and genetic profile are limited. In this study, we reported 10 patients who presented mainly with periodic fever syndrome or arthritis. Next-generation sequencing (NGS) identified 6 heterozygous mutations of NLRP12, including 2 novel null mutations. Of the patients, some with same mutations showed different clinical features. Compared to healthy controls, the increased levels of cytokines were revealed in the patients' plasmas, as well as in the supernatants of patients’ cells stimulated with lipopolysaccharide (LPS) or tumor necrosis factor-α (TNF-α). The missense mutations did not change the protein expression;but decreased level of NLRP12 protein was shown in the null mutations. And in vitro expression assay demonstrated a truncating protein induced by the frameshift mutation. Further functional studies revealed the deleterious effect of mutations on nuclear factor-kappa B (NF-κB) signaling. Both the null and missense mutations impaired their inhibition of NF-κB activation induced by p65. Collectively, this study reported a relatively large NLRP12-AID case series. Our findings expand the clinical spectrum, and reinforce the diversity of genetic mutations and clinical phenotypes. The NLRP12-associated disorder should be considered when autoinflammatory diseases are encountered in the clinical practice, especially for patients presenting with periodic fever but no other genetic cause identified.