• Biomedical Science Letters
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• v.26 no.4
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• pp.256-266
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• 2020

Carboxypeptidase D (CPD) is a zinc-dependent protease, which is highly expressed in macrophages, and is thought to participate in inflammatory processes. In the present study, we investigated the possible regulatory effect of all-trans retinoic acid (ATRA), which is an active form of vitamin A and plays a critical regulatory role in both the innate and adaptive immunity, on CPD expression and secretion in human monocytic THP-1 cells. CPD mRNA expression first increased, from a concentration as low as 10 nM ATRA to a maximum level of expression, at 1 μM. ATRA enhanced intracellular CPD expression in a time- and concentration-dependent manner but did not affect cell surface CPD expression. Interestingly, 9-cis-RA did not affect CPD expression. Additionally, an experiment with RAR/RXR selective agonist or antagonists demonstrated that ATRA-induced enhancement of CPD expression was RAR/RXR dependent. ATRA also enhanced CPD secretion from THP-1 cells; however, this enhancement was RAR/RXR-independent. The anti-inflammatory agent dexamethasone reversed ATRA-induced enhancement of CPD expression and secretion. Our results suggest ATRA exerts regulatory effects on expression and secretion of CPD in human monocytes, and ATRA-induced CPD secretion may be associated with inflammatory response.

• The Journal of Internal Korean Medicine
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• v.31 no.1
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• pp.25-39
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• 2010

Background : At high glucose levels in $\beta$-cells, cell viability and insulin secretion are decreased by glucotoxicity. Sopyung-tang(SPT) had an effect on blood glucose level decrease and antioxidant enzyme activities in streptozotocin-induced diabetic rats. Objectives : This study performed a series of experiment to verify the effects of SPT extract on the cell viability, antioxidant enzyme activities, insulin secretion and insulin mRNA expression at hyperglycemic states of RIN-m5F. Methods : After treatment at various concentrations of SPT added to the RIN-m5F cells, cell viability by MTT assay, free radical-scavenging activity, SOD activity and insulin secretion were measured. Additionally, insulin-related gene expression was measured using real-time RT-PCR. Results : Compared to the control group, SPT extract showed considerable effects on RIN-m5F cell viability, DPPH radical-scavenging activity, superoxide dismutase (SOD) activity, insulin secretion and insulin-related gene expression. Conclusions : This study showed that SPT extract has an effect on $\beta$-cell cell viability, insulin secretion and insulin-related gene expression. Thus, SPT extract may be used for treatment of diabetes and its complications. Further mechanism studies of SPT seem to be necessary on the glucotoxicity and oxidative stress.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1422-1428
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• 2006

An ABC transporter apparatus of the Gram-negative bacterial type I secretion pathway can be used as a secretory protein expression system in Escherichia coli. Four types of coexpression systems for the Pseudomonas fluorescens lipase gene, tliA, and its cognate ABC transporter gene cluster, tliDEF, were constructed. When the relative expression levels were changed by adding different concentrations of IPTG, the secretion (16.9 U/ml of culture) of TliA in E. coli [pTliDEFA-223+pACYC184] was significantly higher than E. coli [pKK223-3+pTliDEFA-184] secreting the lowest level of TliA (5.2 U/ml of culture). Maximal accumulation of the lipase secreted occurred in the mid-exponential phase, implying that the efficient protein secretion via an ABC transporter was restricted only to actively growing cells. Finally, the secretion level of TliA in E. coli [pTliDEFA-223+pACYC184] was increased to 26.4 U/ml by inducing gene expression at the culture initiation time. These results indicate that a significant increase in the ABC transporter-dependent protein secretion can be achieved by simply controlling the relative expression levels between the ABC transporter and its passenger protein, even in the recombinant E. coli cells.

• Toxicological Research
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• v.9 no.2
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• pp.195-206
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• 1993

The expression of proenkephalin (proENK) mRNA and Met-enkephalin (ME) secretion in C6 rat glioma cells and bovine adrenal medullary chromaffin (BAMC) cells were elucidated in the present study. The levels of proENK mRNA and ME secreted into the media in BAMC cells were measured in the presence of cycloheximide and 12-tetrade-canoylphorbol-13-acetate (TPA). Cycloheximide (20 nM) abolished the induction of proENK mRNA expression, protein synthesis and ME secretion by TPA (1nM), indicating that de novo protein synthesis was necessary for proENK gene expression and ME secretion.

• Journal of Community Nutrition
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• v.8 no.2
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• pp.69-75
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• 2006

Adipose tissue has now been recognized as a rich source of metabolically active molecules that include leptin and angiotensinogen (AGT), the precursor of angiotensin II (Ang II). Both of which have been implicated in the pathogenesis of metabolic alteration and hypertension associated with obesity. In this study, we examined the relationship between body mass index (BMI), adipocyte size, leptin, Ang II secretion and mRNA expression in human adipose tissue obtained from female subjects. Leptin and Ang II were analyzed using specific radioimmunoassay kits following a 48hour tissue culture. Leptin and Ang II secretion varied from 1.4 - 72.1ng/g and 0.8 - 57.3pg/g of tissue respectively. These large individual variations limit significant correlation between BMI, leptin and Ang II secretion. Ang II secretion was significantly higher in the obese than the non-obese (p < 0.05) and positively correlated with BMI. However, no difference in leptin secretion between the obese and the non-obese was observed and leptin secretion showed negative correlation with BMI. No difference in leptin and AGT mRNA expression in adipose tissue between the obese and the non-obese was observed. Although several limitations of this study, we found increased Ang II secretion in obese patients compared with non-obese patients, and positive correlation between AGT and BMI. Observed difference in AGT expression between the obese and the non-obese in this study might be of importance in relation with obesity related hypertension. (J Community Nutrition 8(2): 69-75, 2006)

• The Journal of Korean Medicine
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• v.29 no.3
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• pp.76-87
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• 2008

Objectives: In this study, the author investigated whether Haengso-tang (HST) and Chwiyeon-tang (CHT) affect both in vitro mucin secretion and MUC5AC gene expression in airway epithelial cells and in vivo mucin secretion from animal model for airway mucus hypersecretion. Materials and Methods: Confluent HTSE cells (non-labeled) were chased for 30 min in the presence of HST and CHT to assess the effects of the agents on mucin secretion by enzyme-linked immunosorbent assay (ELISA), with removal of oriental herbal medicine extract from each agent-treated sample by centrifuge microfilter. Also, the effects of the agents on TNF- or EGF-induced MUC5AC gene expression in human airway epithelial cells (NCI-H292) were investigated. The author also induced hypersecretion of airway mucus by exposure of rats to SO2 for 3 weeks. Effects of orally-administered HST and CHT during 1 week on in vivo mucin secretion from tracheal goblet cells of rats were assessed using ELISA. Results: (1) HST significantly decreased in vitro mucin secretion from cultured HTSE cells. However, CHT did not affect in vitro mucin secretion from HTSE cells; (2) CHT significantly inhibited the expression levels of EGF- or TNF-alpha-induced MUC5AC gene in NCI-H292 cells. However, HST did not affect the expression levels of EGF- or TNF-alpha-induced MUC5AC gene in NCI-H292 cells; (3) CHT significantly inhibited hypersecretion of in vivo mucin. However, HST did not affect hypersecretion of in vivo mucin. Conclusion: These results suggest that CHT can not only affect the secretion of mucin but also the expression of the mucin gene and could be helpful for treating pulmonary disease caused by secretion of mucin.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.258-265
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• 1997

The effects of medium pH and culture temperature on the expression and secretion of inulinase and invertase were investigated with recombinant Saccharomyces cerevisiae cells. These cells were obtained by transformation of 2$\mu$-based plasmids pYI10 and pYS10 which contain Kluyveromyces marxianus inulinase gene (INU1A) and S. cerevisiae invertase gene (SUC2), respectively, in the downstream of GAL1 promoter. The expression level and localization of inulinase and invertase were not affected significantly by the initial medium pH: secretion efficiencies of inulinase and invertase into the medium were about 90% and 60%, respectively, in the pH ranges of 4.0 to 6.5. However, the expression and secretion of both enzymes were strongly dependent on the culture temperature. The highest expression (7.7 units/mL) and secretion (6.7 units/mL) of inulinase were observed at 28$\circ$C and 30$\circ$C. As a consequence of decreased localization of inulinase in the periplasmic space, the secretion efficiency increased from 68% at 20$\circ$C, to 95% at 35$\circ$C,. The total expression level and secretion efficiency of invertase increased from 19 units/mL and 55% at 20$\circ$C to 25 units/mL and 68% at 35$\circ$C, respectively. Irrespective of the culture temperature, the invertase activity in the cellular fraction (periplasmic space and cytoplasmic fractions) was kept constant at around 33-45%.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.485-493
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• 2006

Lactococcus species are noninvasive and nonpathogenic microorganisms that are widely used in industrial food fermentation and as well-known probiotics. They have been modified by traditional methods and genetic engineering to produce useful food-grade materials. The application of genetically modified lactococci in the food industry requires their genetic elements to be safe and stable from integration with endogenous food microorganisms. In addition, selection for antibiotic-resistance genes should be avoided. Several expression and secretion signals have been developed for the production and secretion of useful proteins in lactococci. Food-grade systems composed of genetic elements from lactic acid bacteria have been developed. Recent developments in this area have focused on food-grade selection markers, stabilization, and integration strategies, as well as approaches for controlled gene expression and secretion of foreign proteins. This paper reviews the expression and secretion signals available in lactococci and the development of food-grade markers, food-grade cloning vectors, and integrative food-grade systems.

• Natural Product Sciences
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• v.23 no.1
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• pp.29-34
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• 2017

In this study, we investigated whether adenosine, adenine, uridine and homogentisic acid derived from Pinellia ternata affect the secretion, production and gene expression of MUC5AC mucin from airway epithelial cells. Confluent NCI-H292 cells were pretreated with adenosine, adenine, uridine or homogentisic acid for 30 min and then stimulated with PMA (phorbol 12-myristate 13-acetate) for 24 h. The MUC5AC mucin gene expression, mucin protein production and secretion were measured by RT-PCR and ELISA, respectively. The results were as follows: (1) Adenine and homogentisic acid decreased PMA-induced MUC5AC mucin gene expression, although adenosine and uridine did not affect the mucin gene expression; (2) Adenosine, adenine, uridine and homogentisic acid inhibited PMA-induced MUC5AC mucin production; (3) Homogentisic acid inhibited the secretion of MUC5AC mucin from NCI-H292 cells. These results suggest that, among the four compounds examined, homogentisic acid showed the regulatory effect on the steps of gene expression, production and secretion of mucin, by directly acting on airway epithelial cells.

• Journal of Microbiology and Biotechnology
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• v.21 no.7
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• pp.679-685
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• 2011

Xanthomonas oryzae pv. oryzae (Xoo) produces a putative effector, XoAvrBs2. We expressed XoAvrBs2 homologously in Xoo with a TAP-tag at the C-terminus to enable quantitative analysis of protein expression and secretion. Addition of rice leaf extracts from both Xoo-sensitive and Xoo-resistant rice cultivars to the Xoo cells induced expression of the XoAvrBs2 gene at the transcriptional and translational levels, and also stimulated a remarkable amount of XoAvrBs2 secretion into the medium. In a T3SS-defective Xoo mutant strain, secretion of the TAPtagged XoAvrBs2 was blocked. Thus, we elucidated the transcriptional and translational expressions of the XoAvrBs2 gene in Xoo was induced in vitro by the interaction with rice and the induced secretion of XoAvrBs2 was T3SSdependent. It is the first report to measure the homologous expression and secretion of XoAvrBs2 in vitro by rice leaf extract. Our system for the quantitative analysis of effector protein expression and secretion could be generally used for the study of host-pathogen interactions.