1.Comparison of immunophenotypes between Rag2 knockout mice derived from two different sources
Yu Jeong ROH ; Jeong Eun GONG ; Ji Eun KIM ; You Jeong JIN ; Hee Jin SONG ; Ayun SEOL ; Jumin PARK ; Yong LIM ; Dae Youn HWANG
Laboratory Animal Research 2023;39(1):12-25
Background:
Recombination activating gene2 (Rag2) knockout (KO) mice are used widely in various research fields, including vaccine development, transplantation studies, and hematopoiesis research, but few studies have compared their phenotypes. This study examined whether there were differences in the immunophenotypes between Rag2 KO mice derived from different sources. In particular, the changes in the organ weight, histological structure, and subpopulation of T and B cells were compared in the spleen and thymus of C57BL/6-Rag2em1hwl/Korl (Rag2/Korl KO) and B6.Cg-Rag2tm1.1Cgn/J (Rag2/J KO) mice.
Results:
The weight of the spleen and thymus similarly decreased in the Rag2/Korl and Rag2/J KO mice compared to their wild type (WT) mice, even though the other organs were kept at the same weight. A slight difference between the Rag2/Korl and Rag2/J KO group were detected in the number of white blood cells (WBC), lymphocytes (LYM), red cell distribution width (RDW), and platelets (PLT). In addition, the white pulp of the spleen and the cortex region of the thymus decreased in both Rag2 KO mice compared to WT mice. On the other hand, significant differences in the number of CD8+ T and B cell subpopulations between WT and Rag2 KO mice were observed between Rag2/Korl and Rag2/J KO group, while the CD4+ T subpopulation was maintained similarly in both groups.
Conclusions
These results suggest that Rag2/Korl and Rag2/J KO mice exhibit similar immunophenotypes in the spleen and thymus except for the differences in the number of CD8+ T and B cell subpopulations.
2.Improvement of the intestinal epithelial barrier during laxative effects of phlorotannin in loperamide‑induced constipation of SD rats
Ji Eun KIM ; Hee Jin SONG ; Yun Ju CHOI ; You Jeong JIN ; Yu Jeong ROH ; Ayun SEOL ; So Hae PARK ; Ju Min PARK ; Hyun Gu KANG ; Dae Youn HWANG
Laboratory Animal Research 2023;39(1):1-11
Background:
Disruptions of the intestinal epithelial barrier (IEB) are frequently observed in various digestive diseases, including irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). This study assessed the improvement in the IEB during the laxative activity of phlorotannin (Pt) harvested from Ecklonia cava in constipation by examining the changes in the expression of the regulatory proteins for the tight junction (TJ) and adherens junction (AJ), and inflammatory cytokines in Sprague Dawley (SD) rats with loperamide (Lm)-induced constipation after a Pt treatment.
Results:
The Pt treatment induced laxative activity, including the improvement of feces-related parameters, gastrointestinal transit rate, and histological structure of the mid colon in Lm-treated SD rats. In addition, significant recovery effects were detected in the histology of IEB, including the mucus layer, epithelial cells, and lamina propria in the midcolon of Lm + Pt treated SD rats. The expression levels of E-cadherin and p120-catenin for AJ and the ZO-1, occludin, and Claudin-1 genes for TJ in epithelial cells were improved remarkably after the Pt treatment, but the rate of increase was different. Furthermore, the Pt treatment increased the expression level of several inflammatory cytokines, such asTNF-α, IL-6, IL-1β, IL-13, and IL-4 in Lm + Pt treated SD rats.
Conclusions
These results provide the first evidence that the laxative activity of Pt in SD rats with Lm-induced constipation phenotypes involve improvements in the IEB.
3.Compositional changes in fecal microbiota in a new Parkinson’s disease model:C57BL/6‑Tg(NSE‑haSyn) mice
Ji Eun KIM ; Ki Chun KWON ; You Jeong JIN ; Ayun SEOL ; Hee Jin SONG ; Yu Jeong ROH ; Tae Ryeol KIM ; Eun Seo PARK ; Gi Ho PARK ; Ji Won PARK ; Young Suk JUNG ; Joon Yong CHO ; Dae Youn HWANG
Laboratory Animal Research 2023;39(4):371-384
Background:
The gut–brain axis (GBA) in Parkinson’s disease (PD) has only been investigated in limited mice models despite dysbiosis of the gut microbiota being considered one of the major treatment targets for neurodegenerative disease. Therefore, this study examined the compositional changes of fecal microbiota in novel transgenic (Tg) mice overexpressing human α-synuclein (hαSyn) proteins under the neuron-specific enolase (NSE) to analyze the potential as GBA model.
Results:
The expression level of the αSyn proteins was significantly higher in the substantia nigra and striatum of NSEhαSyn Tg mice than the Non-Tg mice, while those of tyrosine hydroxylase (TH) were decreased in the same group. In addition, a decrease of 72.7% in the fall times and a 3.8-fold increase in the fall number was detected in NSE-hαSyn Tg mice. The villus thickness and crypt length on the histological structure of the gastrointestinal (GI) tract decreased in NSE-hαSyn Tg mice. Furthermore, the NSE-hαSyn Tg mice exhibited a significant increase in 11 genera, including Scatolibacter, Clostridium, Feifania, Lachnoclostridium, and Acetatifactor population, and a decrease in only two genera in Ligilactobacillus and Sangeribacter population during enhancement of microbiota richness and diversity.
Conclusions
The motor coordination and balance dysfunction of NSE-hαSyn Tg mice may be associated with compositional changes in gut microbiota. In addition, these mice have potential as a GBA model.
4.Chemosensitivity to doxorubicin in primary cells derived from tumor of FVB/N‑Trp53tm1Hw1 with TALEN‑mediated Trp53 mutant gene
Woobin YUN ; Ji Eun KIM ; You Jeong JIN ; Yu Jeong ROH ; Hee Jin SONG ; Ayun SEOL ; Tae Ryeol KIM ; Kyeong Seon MIN ; Eun Seo PARK ; Gi Ho PARK ; Hyun Gu KANG ; Yeon Shik CHOI ; Dae Youn HWANG
Laboratory Animal Research 2023;39(4):287-297
Background:
To evaluate the chemosensitivity to doxorubicin (DOX) in two primary cells derived from a tumor of FVB/N-Trp53tm1Hw1 knockout (KO) mice with TALEN-mediated Trp53 mutant gene, we evaluated the cell survivability, cell cycle distribution, apoptotic cell numbers and apoptotic protein expression in solid tumor cells and ascetic tumor cells treated with DOX.
Results:
The primary tumor cells showed a significant (P < 0.05) defect for UV-induced upregulation of the Trp53 pro-tein, and consisted of different ratios of leukocytes, fibroblasts, epithelial cells and mesenchymal cells. The IC50 level to DOX was lower in both primary cells (IC50 = 0.12 μM and 0.20 μM) as compared to the CT26 cells (IC50 = 0.32 μM), although the solid tumor was more sensitive. Also, the number of cells arrested at the G0/G1 stage was significantly decreased (24.7–23.1% in primary tumor cells treated with DOX, P < 0.05) while arrest at the G2 stage was enhanced to 296.8–254.3% in DOX-treated primary tumor cells compared with DOX-treated CT26 cells. Furthermore, apoptotic cells of early and late stage were greatly increased in the two primary cell-lines treated with DOX when compared to same conditions for CT26 cells. However, the Bax/Bcl-2 expression level was maintained constant in the primary tumor and CT26 cells.
Conclusions
To the best of our knowledge, these results are the first to successfully detect an alteration in chemosensitivity to DOX in solid tumor cells and ascetic tumor cells derived from tumor of FVB/N-Trp53tm1Hw1 mice TALENmediated Trp53 mutant gene.