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Irritable bowel syndrome is a chronic disorder affecting the gastrointestinal tract, negatively impacting patients' quality of life. Here, we aimed to evaluate the effects of Lacticaseibacillus rhamnosus IDCC 3201 (RH 3201) on irritable bowel syndrome with constipation (IBS-C). In this randomised, double-blind, placebo-controlled trial, a total of 30 subjects with IBS-C were randomly assigned (1:1) to receive 8 weeks of probiotics administration or placebo. Concerning bowel activities, both irritant bowel movements and discomfort caused by constipation showed significant improvement with RH 3201 at 8 weeks. Symptoms including severity of abdominal bloating, frequency of abdominal bloating, and satisfaction of bowel habits based on the irritable bowel syndrome-severity scoring system also ameliorated in the probiotic group. Analysis of the fecal microbiome revealed that the abundance of Bacteroides cellulosilyticus and Akkermansia muciniphila was higher during the period of RH 3201 administration compared to the placebo. Untargeted metabolome analysis further suggested a correlation between specific metabolites, such as N-acetylornithine, xanthine, and 3-phenylpropionic acid, and the improvement of clinical symptoms. These results indicate that RH 3201 was effective in ameliorating IBS-C, potentially by enriching beneficial microbes and associated metabolites in the gut environment., (© 2024. The Author(s).)

Korean red ginseng has been widely used as an herbal medicine. Red ginseng dietary fiber (RGDF) is a residue of the processed ginseng product but still contains bioactive constituents that can be applied as prebiotics. In this study, we evaluated changes on fermentation profiles and probiotic properties of strains that belong to family Lactobacillaceae with RGDF supplementation. Metabolomic analyses were performed to understand specific mechanisms on the metabolic alteration by RGDF and to discover novel bioactive compounds secreted by the RGDF-supplemented probiotic strain. RGDF supplementation promoted short-chain fatty acid (SCFA) production, carbon source utilization, and gut epithelial adhesion of Lactiplantibacillus plantarum and inhibited attachment of enteropathogens. Intracellular and extracellular metabolome analyses revealed that RGDF induced metabolic alteration, especially associated with central carbon metabolism, and produced RGDF-specific metabolites secreted by L. plantarum , respectively. Specifically, L. plantarum showed decreases in intracellular metabolites of oleic acid, nicotinic acid, uracil, and glyceric acid, while extracellular secretion of several metabolites including oleic acid, 2-hydroxybutanoic acid, hexanol, and butyl acetate increased. RGDF supplementation had distinct effects on L. plantarum metabolism compared with fructooligosaccharide supplementation. These findings present potential applications of RGDF as prebiotics and bioactive compounds produced by RGDF-supplemented L. plantarum as novel postbiotic metabolites for human disease prevention and treatment., Competing Interests: S-HY and S-KK were employed by Korea Ginseng Corporation. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Jeon, You, Nam, Truong, Bang, Bae, Rarison, Kim, Jeong, Jung and Shin.)

Scope: Chronic hypernutrition promotes lipid accumulation in the body and excessive lipid accumulation leads to obesity. An increase in the number and size of adipocytes, a characteristic of obesity is closely associated with adipose dysfunction. Recent in vitro and in vivo studies have shown that probiotics may prevent this dysfunction by regulating lipid metabolism. However, the mechanisms of action of probiotics in obesity are not fully understood and their usage for treating obesity remains limited., Methods and Results: Bifidobacterium lactis IDCC 4301 is selected for its anti-obesity potential after evaluating inhibitory activity of pancreatic lipase and cholesterol reducing activity. Next, this study investigates the roles of B. lactis IDCC 4301 on lipid metabolism in 3T3-L1 preadipocytes and high-fat diet (HFD)-fed mice. B. lactis IDCC 4301 inhibits cell differentiation and lipid accumulation by suppressing the expression of adipogenic enzymes in 3T3-L1 cells. Moreover, the administration of B. lactis IDCC 4301 decreases body and adipose tissue weight, improves serum lipid levels, and downregulates adipogenic mRNA expression in HFD-fed mice. Additionally, metabolomic analysis suggests that 2-ketobutyrate should be a possible target compound against obesity., Conclusions: B. lactis IDCC 4301 may be used as an alternative treatment for obesity., (© 2022 Wiley-VCH GmbH.)

Fibroblast activation protein (FAP) belongs to the family of prolyl-specific serine proteases and displays both exopeptidase and endopeptidase activities. FAP expression is undetectable in most normal adult tissues, but is greatly upregulated in sites of tissue remodeling, which include fibrosis, inflammation and cancer. Due to its restricted expression pattern and dual enzymatic activities, FAP inhibition is investigated as a therapeutic option for several diseases. In the present study, we described the structure-activity relationship of several synthesized compounds against DPPIV and prolyl oligopeptidase (PREP). In particular, BR102910 (compound 24) showed nanomolar potency and high selectivity. Moreover, the in vivo FAP inhibition study of BR102910 (compound 24) using C57BL/6J mice demonstrated exceptional profiles and satisfactory FAP inhibition efficacy. Based on excellent in vitro and in vivo profiles, the potential of BR102910 (compound 24) as a lead candidate for the treatment of type 2 diabetes is considered., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Fibroblast growth factor (FGF) 21 is a class of hepatokines that plays a protective role against obesity, insulin resistance, and liver damage. Despite this, protective effects of FGF21 in human appear to be minimal, possibly due to its proteolytic cleavage by the fibroblast activation protein (FAP). Here, we presented a novel FAP inhibitor, BR103354, and described its pharmacological activities as a potential therapeutic agent for the treatment of metabolic disorders. BR103354 inhibited FAP with an IC 50 value of 14 nM, showing high selectivity against dipeptidyl peptidase (DPP)-related enzymes and prolyl oligopeptidase (PREP). In differentiated 3T3/L1 adipocytes, the addition of FAP diminished hFGF21-induced Glut1 and phosphorylated levels of ERK, which were restored by BR103354. BR103354 exhibited good pharmacokinetic properties as evidenced by oral bioavailability of 48.4% and minimal hERG inhibition. Single co-administration of BR103354 with hFGF21 reduced nonfasting blood glucose concentrations, in association with increased intact form of hFGF21 in ob/ob mice. Additionally, chronic treatment of BR103354 for 4 weeks reduced nonfasting blood glucose concentrations with improved glucose tolerance and with reduced triglyceride (TG) content in liver of ob/ob mice. Consistently, BR103354 improved hepatic steatosis and fibrosis in a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD)-induced non-alcoholic steatohepatitis (NASH) mouse model. FAP inhibitory effects of BR103354 were confirmed in normal cynomolgus monkeys. Together, BR103354 acts as an effective FAP inhibitor in vitro and in vivo, thereby demonstrating its potential application as an anti-diabetic and anti-NASH agent.

The new class of PPARgamma non-TZD agonist originally derived from the backbone of anti-hypertensive Fimasartan, BR101549, was identified as a potential lead for anti-diabetic drug development. The X-ray crystallography of BR101549 with PPARgamma ligand binding domain (LBD) revealed unique binding characteristics versus traditional TZD full agonists. The lead candidate, BR101549, has been found activating PPARgamma to the level of Pioglitazone in vitro and indeed has demonstrated its effects on blood glucose control in mouse proof-of-concept evaluation. The attempts to improve its metabolic stability profile through follow-up SAR including deuterium incorporation have been also described., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Inspired by the well-known PPARγ partial agonism of angiotensin II type 1 receptor (AT1R) antagonists exemplified by an antihypertensive drug, Telmisartan, efforts to identify compounds with the dual activities have been pursued in order to control the two major metabolic disorders, hypertension and hyperglycemia simultaneously. Lead compound 18 derived from the AT1R antagonist, Fimasartan, has successfully presented the possibility to control the medical conditions by a single molecule., (Copyright © 2018. Published by Elsevier Ltd.)

Bile acids (BAs) control metabolism and inflammation by interacting with several receptors. Here, we report that intravenous infusion of taurodeoxycholate (TDCA) decreases serum pro-inflammatory cytokines, normalizes hypotension, protects against renal injury, and prolongs mouse survival during sepsis. TDCA increases the number of granulocytic myeloid-derived suppressor cells (MDSC LT ) distinctive from MDSCs obtained without TDCA treatment (MDSC L ) in the spleen of septic mice. FACS-sorted MDSC LT cells suppress T-cell proliferation and confer protection against sepsis when adoptively transferred better than MDSC L . Proteogenomic analysis indicated that TDCA controls chromatin silencing, alternative splicing, and translation of the immune proteome of MDSC LT , which increases the expression of anti-inflammatory molecules such as oncostatin, lactoferrin and CD244. TDCA also decreases the expression of pro-inflammatory molecules such as neutrophil elastase. These findings suggest that TDCA globally edits the proteome to increase the number of MDSC LT cells and affect their immune-regulatory functions to resolve systemic inflammation during sepsis.

Epithelial-mesenchymal transition (EMT) is an important process implicated in tumor invasion and metastasis. Twist1 is a transcription factor that induces EMT, including E-cadherin suppression and cancer cell migration and invasion; hence it promotes cancer metastasis. Twist1 directly or indirectly regulates the expression of various genes and cellular functions involved in cancer progression. However, the underlying mechanisms remain largely unknown. In this study, we investigated the molecular basis for Twist1-mediated invasion and EMT. In human cancer cells, Twist1 was found to directly upregulate transcription of the mesenchymal gene integrin α5 in an E-box-independent, but activating protein-1 (AP-1) element-dependent, manner. Twist1 activated the integrin α5 promoter by interacting with and activating the transcription factor AP-1, composed of c-Jun and activating transcription factor-2 (ATF-2); it also enhanced the nuclear presence of ATF-2. AP-1 was critical for Twist1-induced cancer cell invasion, primarily through the induction of integrin α5, which activated c-Jun N-terminal kinase and focal adhesion kinase-signaling activities. Using data from The Cancer Genome Atlas, we found that Twist1 expression positively correlates with integrin α5 expression in human colorectal cancers. These findings suggest that cooperation between Twist1 and AP-1 represents a novel mechanism for EMT and tumor invasiveness. This study supports further investigation into the molecular basis underlying the diverse Twist1-mediated functions that occur during tumor progression., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Epithelial-mesenchymal transition (EMT) is a process implicated in invasion and metastasis. EMT is characterized by repression of epithelial markers and induction of mesenchymal markers. ZEB2 is a transcriptional repressor of E-cadherin, leading to EMT. Previously, we have shown that ZEB2 directly upregulates integrin α5 transcription by cooperating with the transcription factor Sp1. In this study, we investigated the precise mechanism by which ZEB2 modulates invasion and EMT events and the role of Sp1 in ZEB2-induced invasion. We found that ZEB2 directly induced cadherin-11 transcription in an Sp1-dependent, but Smad- and E-box-independent, manner and repressed E-cadherin expression in an Sp1- and Smad-independent manner, leading to cadherin switch. Furthermore, ZEB2 upregulated Sp1 by enhancing Sp1 protein stability, and Sp1 was found to be critical for ZEB2-induced cancer cell invasion, mainly through induction of cadherin-11 and integrin α5. Expression levels of cadherin-11 and integrin α5 were interdependent and both modulated c-Jun N-terminal kinase-signaling activity and invasion. Immunofluorescence analysis showed that nuclear expression of ZEB2 was positively correlated with Sp1 expression in human colorectal cancers. Together, these findings demonstrate a previously unrecognized interplay between ZEB2, Sp1, cadherin-11 and integrin α5 that is, probably, significant in tumor progression and metastasis.

Background: Staphylococcus pseudintermedius is a common pathogen of skin and ear infections in dogs. The widespread and rapid emergence of meticillin-resistant S. pseudintermedius (MRSP) has created therapeutic challenges in veterinary medicine and the need for alternative treatments., Hypothesis/objectives: We aimed to evaluate the in vitro antimicrobial activity of the essential oil manuka (Leptospermum scoparium) against S. pseudintermedius., Methods: This study was performed using S. pseudintermedius strains isolated from dogs with skin and ear infections collected throughout Korea between 2009 and 2011. The in vitro antimicrobial activity of manuka oil against 39 MRSP and 11 meticillin-susceptible S. pseudintermedius (MSSP) strains was analysed by measuring minimal inhibitory concentrations (MICs) using the agar dilution method and biofilm inhibition activity as assessed by the colorimetric microtitre plate assay., Results: Our results indicated that manuka oil had excellent activity against all bacterial isolates. The MICs for MRSP and MSSP to manuka oil were in the range of 2(-9) to 2(-6) and 2(-9) to 2(-7) % (v/v), respectively. Manuka oil was a potent inhibitor of S. pseudintermedius biofilm formation, and the majority of bacteria decreased by >50%. No significant differences were observed in the MICs or biofilm formation between the MRSP and MSSP strains., Conclusions and Clinical Importance: These results suggest that manuka oil has the potential to be a useful therapeutic option for treating superficial infections caused by MRSP and MSSP; further clinical investigations are required., (© 2013 ESVD and ACVD.)

We investigated Malassezia species and genotypes colonizing dogs, comparing those recovered from the ear canal with those from other anatomical body sites, as well as from diseased and healthy skin. The Malassezia isolates were obtained from four types of skin samples, i.e., diseased ear, diseased skin, healthy ear, and healthy skin. Sequences of the 26S ribosomal DNA region, the intergenic spacer 1 (IGS-1) and the internal transcribed spacer 1 (ITS-1) DNA region were analyzed. These confirmed the presence of Malassezia pachydermatis, which could be separated into three main sequence genotype groups (A, B, C). Genotype A was the most common, only two genotype B isolates were recovered from diseased skin lesion and genotype C was more likely to be isolated from ear samples than from other healthy or diseased-skin sites. The present findings provide the basis for further studies of genotypic diversity in M. pachydermatis, as well as their pathogenic potential.

The aim of this study was to investigate the characteristics of canine uropathogenic Escherichia coli (UPEC) and the interaction between canine UPEC and human bladder epithelial cells. Ten E. coli isolates collected from dogs with cystitis were analyzed for antimicrobial resistance patterns, the presence of virulence factors, and biofilm formation. The ability of these isolates to induce cytotoxicity, invade human bladder epithelial cells, and stimulate an immune response was also determined. We observed a high rate of antimicrobial resistance among canine UPEC isolates. All virulence genes tested (including adhesins, iron acquisition, and protectin), except toxin genes, were detected among the canine UPEC isolates. We found that all isolates showed varying degrees of biofilm formation (mean, 0.26; range, 0.07 to 0.82), using a microtiter plate assay to evaluate biofilm formation by the isolates. Cytotoxicity to human bladder epithelial cells by the canine UPEC isolates increased in a time-dependent manner, with a 56.9% and 36.1% reduction in cell viability compared with the control at 6 and 9 h of incubation, respectively. We found that most canine UPEC isolates were able to invade human bladder epithelial cells. The interaction between these isolates and human bladder epithelial cells strongly induced the production of proinflammatory cytokines such as IL-6 and IL-8. We demonstrated that canine UPEC isolates can interact with human bladder epithelial cells, although the detailed mechanisms remain unknown. The results suggest that canine UPEC isolates, rather than dogspecific pathogens, have zoonotic potential.

In humans, skin barrier dysfunction is thought to be responsible for enhanced penetration of allergens. Similar to conditions seen in humans, canine atopic dermatitis (CAD) is characterized by derangement of corneocytes and disorganization of intercellular lipids in the stratum corenum (SC) with decreased ceramide levels. This study was designed to evaluate the effects of a moisturizer containing ceramide on dogs with CAD. Dogs (n = 20, 3~8 years old) with mild to moderate clinical signs were recruited and applied a moisturizer containing ceramide for 4 weeks. Transepidermal water loss (TEWL), skin hydration, pruritus index for canine atopic dermatitis (PICAD) scores, and canine atopic dermatitis extent and severity index (CADESI) scores of all dogs were evaluated. Skin samples from five dogs were also examined with transmission electron microscopy (TEM) using ruthenium tetroxide. TEWL, PICAD, and CADESI values decreased (p < 0.05) and skin hydration increased dramatically over time (p < 0.05). Electron micrographs showed that the skin barrier of all five dogs was partially restored (p < 0.05). In conclusion, these results demonstrated that moisturizer containing ceramide was effective for treating skin barrier dysfunction and CAD symptoms.

The purpose of this study was to evaluate the effects of a topical spray containing 0.0584% hydrocortisone aceponate (HCA) on canine atopic dermatitis (CAD) and to evaluate the skin barrier function during the treatment of CAD. Twenty-one dogs that fulfilled the diagnostic criteria for CAD were included in this study. The HCA spray was applied once a day to the lesions of all dogs for 7 or 14 days. Clinical assessment was performed before (day 0) and after treatment (day 14), and clinical responses were correlated with changes in skin barrier function. CAD severity significantly decreased after 14 days of HCA treatment based on the lesion scores (p < 0.0001), which were determined using the CAD extent and severity index (CADESI-03) and pruritus scores (p < 0.0001) calculated using a pruritus visual analog scale. Transepidermal water loss, a biomarker of skin barrier function, was significantly reduced compared to baseline (day 0) measurements (p = 0.0011). HCA spray was shown to be effective for significantly improving the condition of dogs suffering from CAD. This treatment also significantly improved cut.

Epithelial-mesenchymal transition (EMT) is a process implicated in tumor invasion, metastasis, embryonic development and wound healing. ZEB2 is a transcription factor involved in EMT that represses E-cadherin transcription. Although E-cadherin downregulation is a major event during EMT and tumor progression, E-cadherin reduction is probably not sufficient for full invasiveness. The mechanisms by which E-cadherin transcriptional repressors induce mesenchymal genes during EMT remain largely unknown. Here, we investigated the role of ZEB2 in the induction of integrin α5 during cancer EMT and its underlying mechanism. In human cancer cells, ZEB2 was found to directly upregulate integrin α5 transcription in a manner that is independent of the regulation of E-cadherin expression. Conversely, depletion of ZEB2 by small interfering RNA suppressed integrin α5 expression, leading to reduced invasion. Suppression of integrin α5 inhibited cancer cell invasion, suggesting an important role for integrin α5 in cancer progression. Furthermore, ZEB2 was found to activate the integrin α5 and vimentin promoters by interacting with and activating the transcription factor Sp1, suggesting that cooperation between ZEB2 and Sp1 represents a novel mechanism of mesenchymal gene activation during EMT. These findings increase our understanding of the pathways beyond E-cadherin reduction that regulate mesenchymal gene expression during EMT and cancer progression.

Angiogenesis is a multi-step process that involves the activation, proliferation, and migration of endothelial cells. We have recently shown that TGF-beta1 can induce mouse macrophages to produce VEGF, a potent angiogenic factor. In the present study, we explored whether TGF-beta1 has a similar effect on mouse dendritic cells. First, we show that under hypoxic conditions, TGF-beta1 induced the expression of VEGF transcripts in bone marrow-derived dendritic cells. Overexpression of Smad3/4 further augmented TGF-beta1-induced VEGF transcription, while overexpression of DN-Smad3 decreased VEGF transcription in DC2.4 cells, a mouse dendritic cell line. We also show that TGF-beta1 and Smads are involved in the induction of VEGF protein secretion. Interestingly, under the same conditions, the expression of VEGF receptor 1 (Flt-1) was also elevated at both the transcriptional and protein levels. Additionally, we found that the TGF-beta1-induced VEGF secretion in activated DC2.4 cells has wound-healing properties. Finally, Smad7 and Smurf1 negatively regulated the TGF-beta1-induced and Smad3/4-mediated VEGF expression. Taken together, these results indicate that TGF-beta1 can enhance the expression of VEGF and Flt-1 through the typical Smad pathway in mouse dendritic cells.

In this report, we demonstrate that self-aggregation is an intrinsic problem of bifunctional organocatalysts, especially in the case when the substrates do not have functional groups which are able to bind strongly with catalyst. Due to their self-association phenomena, the enantioselectivity of bifunctional catalysts dramatically decreases with increasing catalyst concentration or decreasing temperature. Thus, when the substrate concentration is kept constant, the enantioselectivity of bifunctional catalysts dramatically increases with decreasing catalyst loading. The ee values obtained at different catalyst concentrations are fairly consistent with the diffusion coefficients (D) of the catalysts, strongly indicating that their degree of self-association plays a crucial role in determining their enantioselectivity.

TMPRSS4 is a novel type II transmembrane serine protease that is highly expressed on the cell surface in pancreatic, thyroid and other cancer tissues, although its oncogenic significance and molecular mechanisms are unknown. Previously, we have shown that TMPRSS4 promotes invasion, migration and metastasis of human tumor cells by facilitating an epithelial-mesenchymal transition (EMT). In this study, we explored the molecular basis underlying TMPRSS4-mediated effects. We show that multiple downstream signaling pathways, including focal adhesion kinase (FAK), extracellular signal-regulated kinase (ERK), Akt, Src and Rac1, are activated by TMPRSS4 expression and that FAK signaling and ERK activation are required for TMPRSS4-induced invasiveness and EMT, including cadherin switch. Inhibition of PI3K or Src reduced invasiveness and actin rearrangement mediated by TMPRSS4 without restoring E-cadherin expression. Downregulation of E-cadherin was required for TMPRSS4-mediated effects but was not sufficient to induce EMT and invasion. TMPRSS4 induced integrin alpha5 expression and its signal transduction, leading to invasiveness and EMT accompanied by downregulation of E-cadherin. Functional blocking confirmed that integrin alpha5beta1 is a critical signaling molecule that is sufficient to induce TMPRSS4-mediated effects. Immunohistochemical analysis showed that TMPRSS4 expression was significantly higher in human colorectal cancer tissues from advanced stages than in that of early stage. Furthermore, upregulation of TMPRSS4 was correlated with enhanced integrin alpha5 expression. These observations implicate integrin alpha5 upregulation as a molecular mechanism by which TMPRSS4 induces invasion and contributes to cancer progression.

TGF-beta1 is well known to induce Ig germ-line alpha (GLalpha) transcription and subsequent IgA isotype class switching recombination (CSR). Homeodomain protein TG-interacting factor (TGIF) and E3-ubiquitin ligases TGIF interacting ubiquitin ligase 1 (Tiul1) are implicated in the negative regulation of TGF-beta signaling. In the present study, we investigated the roles of Tiul1 and TGIF in TGFbeta1-induced IgA CSR. We found that over-expression of Tiul1 decreased TGFbeta1-induced GLalpha promoter activity and strengthened the inhibitory effect of Smad7 on the promoter activity. Likewise, overexpression of TGIF also diminished GLalpha promoter activity and further strengthened the inhibitory effect of Tiul1, suggesting that Tiul1 and TGIF can down-regulate TGFbeta1-induced GLalpha expression. In parallel, overexpression of Tiul1 decreased the expression of endogenous IgA CSR-predicitive transcripts (GLT(alpha), PST(alpha), and CT(alpha)) and TGFbeta1-induced IgA secretion, but not GLT(gamma3) and IgG3 secretion. Here, over-expressed TGIF further strengthened the inhibitory effect of Tiul1. These results suggest that Tiul1 and TGIF act as negatively regulators in TGFbeta1-induced IgA isotype expression.

TGF-beta1 induces Ig germ-line alpha (GLalpha) transcription and subsequent class switching recombination (CSR) to IgA. In the present study, we investigated the roles of two E3-ubiquitin ligases, Smurfs (HECT type) and Arkadia (RING finger type) on TGFbeta1-induced IgA CSR. We found that over-expression of Smurf1 and Smurf2 decreased TGFbeta1-induced GLalpha promoter activity and strengthened the inhibitory effect of Smad7 on the promoter activity. Further, over-expression of Smurf1 and Smurf2 decreased both Smad3/4-mediated and Runx3-mediated GLalpha promoter activities, suggesting that the Smurfs can down-regulate the major TGF-beta1 signaling pathway and decrease GLalpha gene expression. In parallel, the over-expressed Smurf1 decreased the expression of endogenous IgA CSR-predictive transcripts (GLT(alpha), PST(alpha), and CT(alpha)) and also TGFbeta1-induced IgA secretion. Conversely over-expression of Arkadia abolished the inhibitory effect of Smad7 on TGFbeta1-induced GLT(alpha) expression and IgA secretion. Similar results were obtained in the presence of over-expressed Smad7 and Smurf1. These results indicate that Arkadia can amplify TGFbeta1-induced IgA CSR by degrading Smad7, which interacts with Smurf1. We conclude that Smurf and Arkadia have opposite roles in the regulation of TGFbeta1-induced IgA isotype expression.

In this report, we studied DHX32 expression in human Jurkat T cells. Co-stimulation of CD3 and CD28 resulted in upregulation of DHX32. No significant changes in the expression of the closely related RNA helicases were seen. Ionomycin treatment alone was sufficient to upregulate the expression of DHX32 mRNA isoform transcribed from the proximal promoter. We cloned DHX32 proximal promoter and identified a 218bp fragment containing two potential binding sites for the transcription factor nuclear factor of activated T cells (NF-AT). Mutation of core sequence of NF-AT resulted in reduced transcriptional activity, with more reduction observed in the second NF-AT site. Electrophoretic mobility shift assay results were consistent with a specific binding of NF-AT from ionomycin stimulated nuclear extract of Jurkat cells to oligonucleotide probes from DHX32 proximal promoter. These results suggest that the DHX32 expression is modulated in Jurkat T cells via a pathway that involves NF-AT.