Decreased MIZ1 Expression in Severe Experimental Acute Pancreatitis: A Rat Study

Effects of enteral nutrition on pro-inflammatory factors and intestinal barrier function in patients with acute severe pancreatitis

The main objective of this study was to explore the effect of enteral nutrition on serum pro-inflammatory cytokines, tumor necrosis factor, and intestinal barrier function in patients with acute severe pancreatitis. A total number of 140 patients were recruited and divided randomly into parenteral nutrition (PN) and enteral nutrition (EN) groups. They received parenteral nutrition and enteral nutrition, respectively. The levels of serum total protein (TP) and albumin (ALB) in peripheral blood were detected in the two groups. Interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNFα) in the two groups were comparatively analyzed. The levels of pro-inflammatory factors (IL-1β, IL-6, and TNFα) for both groups were same, and there was no significant difference ( P < 0.05) between the two groups before treatment. However, after treatment, a significant reduction was found in EN group which were 31.16 ± 1.95, 36.09 ± 9.44, and 29.21 ± 3.85 ng/L, respectively, showing significant lower values as compared to PN group. The levels of TP and ALB in EN group were 64.46 ± 3.77 and 27.19 ± 1.56 g/L, respectively, after treatment, showing significantly ( P < 0.05) elevated values than PN group. The incidence rates of pancreatic necrosis and pancreatic abscess in EN group were 28.57% and 11.43%, respectively, which were found to be lower significantly than PN group. Enteral nutrition is found to be more effective than parenteral nutrition in the treatment of severe acute pancreatitis, which can significantly reduce the level of pro-inflammatory factors as well as the degree of systemic inflammatory response and protect the intestinal barrier function; thus, this study is worthy for awareness and application in clinical practice.

Alprostadil combined with somatostatin for treatment of severe acute pancreatitis: Clinical efficacy and impact on inflammatory factors

AIM

To observe the clinical efficacy of alprostadil combined with somatostatin in the treatment of severe pancreatitis (SAP) and the influence on inflammatory factors.

METHODS

Eighty two patients with SAP treated from April 2013 to May 2017 were enrolled in this study. They were randomly divided into either an observation group or a control group. Both groups were given routine treatments and alprostadil, and the observation group was additionally given somatostatin. After 2 wk of therapy, clinical efficacy, symptom remission time, serum inflammatory factor levels, adverse reaction rate, and mortality rate of the two groups were compared.

RESULTS

The total effective rate was 92.68% (38/41) in the observation group and 75.61% (31/41) in the control group, and there was a significant difference between them (χ² = 4.479, P < 0.05). Times to recovery of bowel pain, intestinal function, and blood amylase as well as hospital stay were significantly shorter in the observation group than in the control group (P < 0.05). The levels of white blood count (WBC), C-reactive protein (CRP), amylase (AMY), alanine transaminase (ALT), alanine transaminase (AST), and creatinine (Cr) in the observation group were significantly lower than those in the control group at 7 d and 14 d after treatment (P < 0.05). The levels of endotoxin, TNF-α, IL-6, and IL-1β in the observation group were significantly lower than those in the control group (P < 0.05). The mortality rate in the observation group (2.44%, 1/41) was significantly lower than that in the control group (17.07%, 7/41) (χ² = 4.986, P < 0.05).

CONCLUSION

Alprostadil combined with somatostatin in the treatment of severe pancreatitis has obvious efficacy and can reduce symptoms and the inflammatory response quickly.

Increased expression of Myc-interacting zinc finger protein 1 in APP/PS1 mice

Myc-interacting zinc-finger protein 1 (Miz1) is a member of the poxvirus and zinc-finger domain/zinc finger transcription factor family. Its transcription activation and repression functions in the nucleus are well elucidated; however its cytoplasmic inflammation function is poorly understood and may be associated with the pathogenesis of Alzheimer's disease (AD). The aim of the present study was to investigate the association between AD and Miz1 expression. In the present study, the expression and distribution of Miz1 in wild-type (WT) and amyloid precursor protein/presenelin-1 (AD) mice was studied using reverse transcription-quantitative polymerase chain reaction, western blot analysis, and immunohistochemical and immunofluorescence staining. The results indicated that Miz1 was significantly upregulated in the cortex of AD mice (P<0.05). Double immunofluorescence labeling revealed that Miz1 protein was predominantly expressed in neurons and astrocytes, as evidenced by co-localization with the dendritic markers microtubule associated protein 2 and glial fibrillary acidic protein, respectively. The results of the present study suggest that the expression of Miz1 in the brain tissue of AD mice may serve an important role in AD pathogenesis.

Structural Insights into c-Myc-interacting Zinc Finger Protein-1 (Miz-1) Delineate Domains Required for DNA Scanning and Sequence-specific Binding

c-Myc-interacting zinc finger protein-1 (Miz-1) is a poly-Cys2His2 zinc finger (ZF) transcriptional regulator of many cell cycle genes. A Miz-1 DNA sequence consensus has recently been identified and has also unveiled Miz-1 functions in other cellular processes, underscoring its importance in the cell. Miz-1 contains 13 ZFs, but it is unknown why Miz-1 has so many ZFs and whether they recognize and bind DNA sequences in a typical fashion. Here, we used NMR to deduce the role of Miz-1 ZFs 1-4 in detecting the Miz-1 consensus sequence and preventing nonspecific DNA binding. In the construct containing the first 4 ZFs, we observed that ZFs 3 and 4 form an unusual compact and stable structure that restricts their motions. Disruption of this compact structure by an electrostatically mismatched A86K mutation profoundly affected the DNA binding properties of the WT construct. On the one hand, Miz1-4^WT was found to bind the Miz-1 DNA consensus sequence weakly and through ZFs 1-3 only. On the other hand, the four ZFs in the structurally destabilized Miz1-4^A86K mutant bound to the DNA consensus with a 30-fold increase in affinity (100 nm). The formation of such a thermodynamically stable but nonspecific complex is expected to slow down the rate of DNA scanning by Miz-1 during the search for its consensus sequence. Interestingly, we found that the motif stabilizing the compact structure between ZFs 3 and 4 is conserved and enriched in other long poly-ZF proteins. As discussed in detail, our findings support a general role of compact inter-ZF structures in minimizing the formation of off-target DNA complexes.

Solution structure of the 13th C2H2 Zinc Finger of Miz-1

Miz-1 is a BTB/POZ transcription factor that contains 13C2H2 Zinc Finger domains (ZF). Miz-1 transactivates and represses the transcription of a myriad of genes involved in many aspects of the biology of the cell. The detailed molecular interactions through which Miz-1 controls transcription, including its specific DNA binding via its ZF domains, remain to be understood and documented. In our effort to shed light into the structural biology of Miz-1, we have undertaken the determination of the structure of all its ZF and the characterization of their interactions with cognate DNA. The structure of ZF 1 to 10 have already been solved and characterized. Here, we present the structure of the synthetic Miz-1 ZF13 determined by 2D (1)H-(1)H NMR.