Insertion mutations at codon 69 (T69-ins insertion) of the human immunodeficiency virus type 1 (H... more Insertion mutations at codon 69 (T69-ins insertion) of the human immunodeficiency virus type 1 (HIV-1) reverse transcriptase confer full resistance to all approved nucleoside reverse transcriptase inhibitors. To date, nearly all reports on T69-ins insertions have described subtypes B and rarely subtypes A, C, and F of HIV-1. Here, we provide the first report of a T69-ins insertion in circulating recombinant form (CRF) 06_cpx in a patient who had been treated with a zidovudine/didanosine combination for 18 months and then shifted to lamivudine, stavudine, and nelfinavir for 76 months. Thereafter, the patient was additively administered Korean red ginseng. This is the first report on the appearance of the T69-ins insertion mutation in CRF HIV-1.
Since cancer is the leading cause of death worldwide, there is an urgent need to understand the m... more Since cancer is the leading cause of death worldwide, there is an urgent need to understand the mechanisms underlying cancer progression and the development of cancer inhibitors. Signal transducer and activator of transcription 3 (STAT3) is a major transcription factor that regulates the proliferation and survival of various cancer cells. Here, dual-specificity phosphatase 3 (DUSP3) was identified as a regulator of STAT3 based on an interaction screening performed using the protein tyrosine phosphatase library. DUSP3 interacted with the C-terminal domain of STAT3 and dephosphorylated p-Y705 of STAT3. In vitro dephosphorylation assay revealed that DUSP3 directly dephosphorylated p-STAT3. The suppressive effects of DUSP3 on STAT3 were evaluated by a decreased STAT3-specific promoter activity, which in turn reduced the expression of the downstream target genes of STAT3. In summary, DUSP3 downregulated the transcriptional activity of STAT3 via dephosphorylation at Y705 and also suppress...
To investigate if Korean red ginseng (KRG) affects vif gene, we determined vif gene over 20 years... more To investigate if Korean red ginseng (KRG) affects vif gene, we determined vif gene over 20 years in 10 long-term slowly progressing patients (LTSP) who were treated with KRG alone and then KRG plus HAART. We also compared these data with those of 21 control patients who did not receive KRG. Control patient group harbored only one premature stop codon (PSC) (0.9%), whereas the 10 LTSP revealed 78 defective genes (18.1%) ( < 0.001). The frequency of small in-frame deletions was found to be significantly higher in patients who received KRG alone (10.5%) than 0% in the pre-KRG or control patients ( < 0.01). Regarding HAART, vif genes containing PSCs were more frequently detected in patients receiving KRG plus HAART than patients receiving KRG alone or control patients ( < 0.01). In conclusion, our current data suggest that the high frequency of deletions and PSC in the vif gene is associated with KRG intake and HAART, respectively.
When primary cancer faces limited oxygen and nutrient supply, it undergoes an epithelial–mesenchy... more When primary cancer faces limited oxygen and nutrient supply, it undergoes an epithelial–mesenchymal transition, which increases cancer cell motility and invasiveness. The migratory and invasive cancer cells often exert aggressive cancer development or even cancer metastasis. In this study, we investigated a novel compound, 3-acetyl-5,8-dichloro-2-((2,4-dichlorophenyl)amino)quinolin-4(1H)-one (ADQ), that showed significant suppression of wound healing and cellular invasion. This compound also inhibited anchorage-independent cell growth, multicellular tumor spheroid survival/invasion, and metalloprotease activities. The anti-proliferative effects of ADQ were mediated by inhibition of the Akt pathway. In addition, ADQ reduced the expression of mesenchymal markers of cancer cells, which was associated with the suppressed expression of Twist1. In conclusion, ADQ successfully suppressed carcinogenic activity by inhibiting the Akt signaling pathway and Twist1, which suggests that ADQ may ...
When primary cancer faces limited oxygen and nutrient supply, it undergoes an epithelial-mesenchy... more When primary cancer faces limited oxygen and nutrient supply, it undergoes an epithelial-mesenchymal transition, which increases cancer cell motility and invasiveness. The migratory and invasive cancer cells often exert aggressive cancer development or even cancer metastasis. In this study, we investigated a novel compound, 3-acetyl-5,8-dichloro-2-((2,4-dichlorophenyl)amino)quinolin-4(1H)-one (ADQ), that showed significant suppression of wound healing and cellular invasion. This compound also inhibited anchorage-independent cell growth, multicellular tumor spheroid survival/invasion, and metalloprotease activities. The anti-proliferative effects of ADQ were mediated by inhibition of the Akt pathway. In addition, ADQ reduced the expression of mesenchymal markers of cancer cells, which was associated with the suppressed expression of Twist1. In conclusion, ADQ successfully suppressed carcinogenic activity by inhibiting the Akt signaling pathway and Twist1, which suggests that ADQ may ...
Since cancer is the leading cause of death worldwide, there is an urgent need to understand the m... more Since cancer is the leading cause of death worldwide, there is an urgent need to understand the mechanisms underlying cancer progression and the development of cancer inhibitors. Signal transducer and activator of transcription 3 (STAT3) is a major transcription factor that regulates the proliferation and survival of various cancer cells. Here, dual-specificity phosphatase 3 (DUSP3) was identified as a regulator of STAT3 based on an interaction screening performed using the protein tyrosine phosphatase library. DUSP3 interacted with the C-terminal domain of STAT3 and dephosphorylated p-Y705 of STAT3. In vitro dephosphorylation assay revealed that DUSP3 directly dephosphorylated p-STAT3. The suppressive effects of DUSP3 on STAT3 were evaluated by a decreased STAT3-specific promoter activity, which in turn reduced the expression of the downstream target genes of STAT3. In summary, DUSP3 downregulated the transcriptional activity of STAT3 via dephosphorylation at Y705 and also suppressed the migratory activity of cancer cells. This study demonstrated that DUSP3 inhibits interleukin 6 (IL-6)/STAT3 signaling and is expected to regulate cancer development. Novel functions of DUSP3 discovered in IL-6/STAT3 signaling regulation would help expand the understanding of cancer development mechanisms. [BMB Reports 2020; 53(6): 335-340]
Small-molecule inhibitors are widely used to treat a variety of inflammatory diseases. In this st... more Small-molecule inhibitors are widely used to treat a variety of inflammatory diseases. In this study, we found a novel antiinflammatory compound, 1-[(2R,4S)-2-methyl-4-(phenylamino)-1,2,3,4-tetrahydroquinolin-1-yl]prop-2-en-1-one (MPQP). It showed strong anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. These effects were exerted through the inhibition of the production of NO and pro-inflammatory cytokines, such as interleukin (IL)-6, IL-1, and tumor necrosis factor- (TNF-). Furthermore, MPQP decreased the expression levels of inducible NO synthase (iNOS) and cyclooxygenase 2 (COX-2). Additionally, it mediated the inhibition of the phosphorylation of p38, c-Jun N-terminal kinase (JNK), the inhibitor of B (IB), and their upstream kinases, IB kinase (IKK) /, mitogen-activated protein kinase kinase (MKK) 3/6, and MKK4. Furthermore, the expression of IL-1 receptor-associated kinase 1 (IRAK1) that regulates NF-B, p38, and the JNK signaling pathways, was also increased by MPQP. These results indicate that MPQP regulates the IRAK1-mediated inflammatory signaling pathways by targeting IRAK1 or its upstream factors. [
This study aimed to develop porous microspheres with a suitable porous structure and mechanical p... more This study aimed to develop porous microspheres with a suitable porous structure and mechanical property for cell delivery using a comparatively low molecular weight (MW) poly(lactide-co-glycolide) (PLGA) having a weak mechanical strength and fast degradation rate, which could be potentially used for treatment of corneal endothelial diseases. Porous microspheres of 30 kDa PLGA with different pore sizes were prepared by varying preparation conditions, and the microspheres with mean pore diameters approximately 0.5, 1, 2 and 3 times that of a single green fluorescent protein-expressing human embryonic kidney 293 cell, used as a model cell, were chosen for cell loading study. The microspheres with an average pore diameter two times greater than that of the single cell were found to be the most appropriate for efficient cell loading in the inner pore spaces, along with demonstrating a good mechanical property, injectability and biodegradability. To maximize the cell loading amount in the microspheres, the cell adhesive property of the microspheres and cell loading conditions were optimized, leading to approximately 4.2 times increase in the cell loading amount. The porous microspheres designed using the low MW PLGA hold promise as a delivery system of corneal endothelial cells for regeneration of the corneal endothelium.
Intercellular adhesion molecule-1 (ICAM-1), which is induced by tumor necrosis factor (TNF)-α, co... more Intercellular adhesion molecule-1 (ICAM-1), which is induced by tumor necrosis factor (TNF)-α, contributes to the entry of immune cells into the site of inflammation in the skin. Here, we show that protein tyrosine phosphatase non-receptor type 21 (PTPN21) negatively regulates ICAM-1 expression in human keratinocytes. PTPN21 expression was transiently induced after stimulation with TNF-α. When overexpressed, PTPN21 inhibited the expression of ICAM-1 in HaCaT cells but PTPN21 C1108S, a phosphatase activity-inactive mutant, failed to inhibit ICAM-1 expression. Nuclear factor-κB (NF-κB), a key transcription factor of ICAM-1 gene expression, was inhibited by PTPN21, but not by PTPN21 C1108S. PTPN21 directly dephosphorylated phospho-inhibitor of κB (IκB)-kinase β (IKKβ) at Ser177/181. This dephosphorylation led to the stabilization of IκBα and inhibition of NF-κB activity. Taken together, our results suggest that PTPN21 could be a valuable molecular target for regulation of inflammation ...
The spores of Lygodium japonicum (Thunb.) Sw. (L. japonicum) have been used in traditional Chines... more The spores of Lygodium japonicum (Thunb.) Sw. (L. japonicum) have been used in traditional Chinese medicine for the treatment of various inflammatory diseases. However, the molecular mechanisms underlying their anti-inflammatory effects have yet to be elucidated. In the present study, we investigated the anti-inflammatory effects of ethanol extracts of L. japonicum spores (ELJ) by measuring the production of inflammatory mediators, and explored the molecular mechanisms underlying the effects of ELJ in murine macrophages in vitro using immunoblotting analyses. At non-cytotoxic concentrations of (50-300 µg/ml), ELJ was revealed to significantly suppress the production of nitric oxide (NO) and tumor necrosis factor (TNF)-α in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophages; ELJ repressed the production of interleukin (IL)-6 only at high concentrations (≥200 µg/ml). The ELJ-mediated decrease in NO production was demonstrated to depend on the downregulation of inducible NO synthase mRNA and protein expression. Conversely, the mRNA and protein expression of cyclooxygenase-2 were not affected by ELJ. In addition, ELJ was revealed to inhibit the mRNA expression of IL-6, IL-1β, and TNF-α in LPS-stimulated RAW 264.7 macrophages. The effects of ELJ on proinflammatory mediators may have been due to the stabilization of inhibitor of κBα and the inhibition of p38 mitogen-activated protein kinase (MAPK). These results suggested that ELJ may suppress LPS-induced inflammatory responses in murine macrophages in vitro, through the negative regulation of p38 MAPK and nuclear factor (NF)-κB. Therefore, ELJ may have potential as a novel candidate for the development of therapeutic strategies aimed at alleviating inflammation.
Spilanthes acmella Murr. (S. acmella) has been used traditionally in India and Sri Lanka to treat... more Spilanthes acmella Murr. (S. acmella) has been used traditionally in India and Sri Lanka to treat various inflammatory diseases. However, the anti‑inflammatory effects and underlying mechanism of action of S. acmella are unclear. The present study assessed the anti‑inflammatory properties of methanol extracts of S. acmella (MSA) in murine macrophages. MSA (≤300 µg/ml) inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)‑stimulated RAW 264.7 macrophages through transcriptional inhibition of inducible nitric oxide synthase expression in a dose‑dependent manner. Furthermore, the LPS‑induced prostaglandin E2 production and cyclooxygenase‑2 expression were inhibited by MSA (300 µg/ml). MSA treatment inhibited interleukin (IL)‑6 production and decreased the mRNA expression levels of proinflammatory cytokines, including IL‑6 and IL‑1β. In addition, no significant inhibition in tumor necrosis factor‑α production was detected. Inhibitory effects of MSA on the production of infl...
The rhizome of Anemarrhena asphodeloides Bunge (A. asphodeloides) has been used as a traditional ... more The rhizome of Anemarrhena asphodeloides Bunge (A. asphodeloides) has been used as a traditional East Asian medicine for the treatment of various types of inflammatory disease. However, to the best of our knowledge, there have been no systemic studies regarding the molecular mechanisms of action of the A. asphodeloides rhizome anti-inflammatory effects. The aim of the present study was to elucidate the anti-inflammatory effects and underlying mechanism of action of ethanol extracts of the rhizome of A. asphodeloides (EAA) in murine macrophages. Non-cytotoxic concentrations of EAA (10-100 µg/ml) significantly decreased the production of NO and interleukin (IL)-6 in lipopolysaccharide (LPS)-stimulated macrophages, while the production of tumor necrosis factor-α was not regulated by EAA. EAA-mediated reduction of nitric oxide (NO) was due to reduced expression levels of inducible NO synthase (iNOS). Furthermore, protein expression levels of LPS-induced cyclooxygenase-2, another inflammatory enzyme, were alleviated in the presence of EAA. EAA-mediated reduction of those proinflammatory mediators was due to inhibition of nuclear factor-κB (NF-κB) and activator protein 1 transcriptional activities followed by the stabilization of inhibitor of κ Bα and inhibition of p38, respectively. These results indicate that EAA suppresses LPS-induced inflammatory responses by negatively regulating p38 and NF-κB, indicating that EAA is a candidate treatment for alleviating inflammation.
Mitogen-activated protein kinases (MAPKs) are involved in a variety of intracellular events such ... more Mitogen-activated protein kinases (MAPKs) are involved in a variety of intracellular events such as gene expression, cell proliferation, and programmed cell death. MAPKs are activated by dual phosphorylation on threonine and tyrosine residues through sequential activation of protein kinases. Recent studies have shown that the protein kinases involved in MAPK signal transductions might be organized into signaling complexes by scaffold proteins. These scaffold proteins are essential regulators that function by assembling the relevant molecular components in mammalian cells. In this study, we report that dual-specificity phosphatase 22 (DUSP22), a member of the protein tyrosine phosphatase family, acts as a distinct scaffold protein in c-Jun N-terminal kinase (JNK) signaling. DUSP22 increased the phosphorylation in the activation loop of JNK regardless of its phosphatase activity but had no effect on phosphorylation levels of ERK and p38 in mammalian cells. Furthermore, DUSP22 selectiv...
International journal of molecular medicine, Jan 21, 2016
Thunbergia alata (Acanthaceae) has been used traditionally to treat various inflammatory diseases... more Thunbergia alata (Acanthaceae) has been used traditionally to treat various inflammatory diseases such as fever, cough and diarrhea in East African countries including Uganda and Kenya. However, systemic studies elucidating the anti-inflammatory effects and precise mechanisms of action of T. alata have not been conducted, to the best of our knowledge. To address these concerns, we explored the anti-inflammatory effects of a methanol extract of T. alata (MTA) in macrophages. Non-cytotoxic concentrations of MTA (≤300 µg/ml) inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)‑stimulated RAW 264.7 macrophages by transcriptional regulation of inducible NO synthase in a dose-dependent manner. The expression of cyclooxygenase-2, the enzyme responsible for the production of prostaglandin E2, was unchanged by MTA at the mRNA and protein levels. MTA treatment inhibited interleukin (IL)-6 production and decreased the mRNA expression of pro‑inflammatory cytokines, including IL-6 ...
Crataeva nurvala Buch. Ham. is an important medicinal plant in India, and its extracts and compon... more Crataeva nurvala Buch. Ham. is an important medicinal plant in India, and its extracts and components were used to treat various inflammatory diseases, such as urinary tract infection, rheumatoid arthritis, and colitis. However, no systemic studies about anti-inflammatory effects of Crataeva nurvala Buch. Ham. and its underlying mechanisms of action have been reported. This study aimed to explore the anti-inflammatory effects of ethanol extracts of Crataeva nurvala Buch. Ham. (ECN). The non-cytotoxic and maximal effective concentration of ECN was determined by measuring the formation of formazan from water-soluble tetrazolium salt in living cells. The inhibitory effect of ECN on nitric oxide (NO) synthesis was measured using Griess reagent, and Enzyme-linked immunosorbent assay (ELISA) was used to measure secreted tumor necrosis factor (TNF)-α and interleukin (IL)-6 protein levels. Furthermore, reverse transcription polymerase chain reaction (RT-PCR) and Western blotting analysis were used to assess the mRNA and protein expression of each inflammatory mediator or relating signaling protein, respectively. A non-cytotoxic concentration of ECN (≤200 μg/ml) significantly reduced the production of NO and IL-6, but not TNF-α, in lipopolysaccharides (LPS)-stimulated RAW 264.7 macrophages. Decreased production of NO by ECN was correlated with reduced expression of iNOS at the mRNA and protein levels. However, cyclooxygenase (COX)-2 expressions at mRNA and protein level were not regulated by ECN. The mRNA expression of IL-6 and IL-1β, but not TNF-α, was also inhibited by ECN treatment in LPS-stimulated RAW 264.7 macrophages. Reduced production of inflammatory mediators by ECN was followed by decreased activity of mitogen-activated protein kinases (MAPKs), especially extracellular signal-regulated kinase (ERK), but not nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). These results indicate that ECN inhibits LPS-induced inflammatory responses via negative regulation of ERK in murine macrophages, suggesting that ECN is a candidate for alleviating severe inflammation.
Myrmecodia platytyrea Becc., a member of the Rubiaceae family, is found throughout Southeast Asia... more Myrmecodia platytyrea Becc., a member of the Rubiaceae family, is found throughout Southeast Asia and has been traditionally used to treat cancer. However, there is limited pharmacological information on this plant. We investigated the anticancer effects of the methanol extract of Myrmecodia platytyrea Becc. leaves (MMPL) and determined the molecular mechanisms underlying the effects of MMPL on metastasis in human hepatocellular carcinoma (HCC) cells. MMPL dose-dependently inhibited cell migration and invasion in SK-Hep1 and Huh7 cells. In addition, MMPL strongly suppressed the enzymatic activity of matrix metalloproteinases (MMP-2 and MMP-9). Diminished telomerase activity by MMPL resulted in the suppression of both telomerase activity and telomerase-associated gene expression. The levels of urokinase-type plasminogen activator receptor (uPAR) expression as well as the phosphorylation levels of signal transducer and activator of transcription 3 (STAT3) and extracellular signal-regulated kinase (ERK) were also attenuated by MMPL. The above results collectively suggest that MMPL has anticancer effects in HCC and that MMPL can serve as an effective therapeutic agent for treating human liver cancer. Semut. This genus is native to Southeast Asia, but it can also be found in Myanmar, Indochina, and northern Queensland in Australia (13). Myrmecodia plants contain a highly specialized tuber and modified stems, which are used by ant colonies (14). Myrmecodia species have traditionally been used to treat diseases such as ulcers, tumors, cancer, hepatitis, and coronary artery disease (15). In pharmacological studies, Myrmecodia pendens and tuberose are both considered to be potential anticancer agents. Water extracts of Myrmecodia pendens have been shown to inhibit HeLa and MCM-B2 cancer cell growth (16). Five flavonoids of Myrmecodia pendens, kaempferol, luteolin, rutin, quercetin, and apigenin, were identified and quantified, and
Insertion mutations at codon 69 (T69-ins insertion) of the human immunodeficiency virus type 1 (H... more Insertion mutations at codon 69 (T69-ins insertion) of the human immunodeficiency virus type 1 (HIV-1) reverse transcriptase confer full resistance to all approved nucleoside reverse transcriptase inhibitors. To date, nearly all reports on T69-ins insertions have described subtypes B and rarely subtypes A, C, and F of HIV-1. Here, we provide the first report of a T69-ins insertion in circulating recombinant form (CRF) 06_cpx in a patient who had been treated with a zidovudine/didanosine combination for 18 months and then shifted to lamivudine, stavudine, and nelfinavir for 76 months. Thereafter, the patient was additively administered Korean red ginseng. This is the first report on the appearance of the T69-ins insertion mutation in CRF HIV-1.
Since cancer is the leading cause of death worldwide, there is an urgent need to understand the m... more Since cancer is the leading cause of death worldwide, there is an urgent need to understand the mechanisms underlying cancer progression and the development of cancer inhibitors. Signal transducer and activator of transcription 3 (STAT3) is a major transcription factor that regulates the proliferation and survival of various cancer cells. Here, dual-specificity phosphatase 3 (DUSP3) was identified as a regulator of STAT3 based on an interaction screening performed using the protein tyrosine phosphatase library. DUSP3 interacted with the C-terminal domain of STAT3 and dephosphorylated p-Y705 of STAT3. In vitro dephosphorylation assay revealed that DUSP3 directly dephosphorylated p-STAT3. The suppressive effects of DUSP3 on STAT3 were evaluated by a decreased STAT3-specific promoter activity, which in turn reduced the expression of the downstream target genes of STAT3. In summary, DUSP3 downregulated the transcriptional activity of STAT3 via dephosphorylation at Y705 and also suppress...
To investigate if Korean red ginseng (KRG) affects vif gene, we determined vif gene over 20 years... more To investigate if Korean red ginseng (KRG) affects vif gene, we determined vif gene over 20 years in 10 long-term slowly progressing patients (LTSP) who were treated with KRG alone and then KRG plus HAART. We also compared these data with those of 21 control patients who did not receive KRG. Control patient group harbored only one premature stop codon (PSC) (0.9%), whereas the 10 LTSP revealed 78 defective genes (18.1%) ( < 0.001). The frequency of small in-frame deletions was found to be significantly higher in patients who received KRG alone (10.5%) than 0% in the pre-KRG or control patients ( < 0.01). Regarding HAART, vif genes containing PSCs were more frequently detected in patients receiving KRG plus HAART than patients receiving KRG alone or control patients ( < 0.01). In conclusion, our current data suggest that the high frequency of deletions and PSC in the vif gene is associated with KRG intake and HAART, respectively.
When primary cancer faces limited oxygen and nutrient supply, it undergoes an epithelial–mesenchy... more When primary cancer faces limited oxygen and nutrient supply, it undergoes an epithelial–mesenchymal transition, which increases cancer cell motility and invasiveness. The migratory and invasive cancer cells often exert aggressive cancer development or even cancer metastasis. In this study, we investigated a novel compound, 3-acetyl-5,8-dichloro-2-((2,4-dichlorophenyl)amino)quinolin-4(1H)-one (ADQ), that showed significant suppression of wound healing and cellular invasion. This compound also inhibited anchorage-independent cell growth, multicellular tumor spheroid survival/invasion, and metalloprotease activities. The anti-proliferative effects of ADQ were mediated by inhibition of the Akt pathway. In addition, ADQ reduced the expression of mesenchymal markers of cancer cells, which was associated with the suppressed expression of Twist1. In conclusion, ADQ successfully suppressed carcinogenic activity by inhibiting the Akt signaling pathway and Twist1, which suggests that ADQ may ...
When primary cancer faces limited oxygen and nutrient supply, it undergoes an epithelial-mesenchy... more When primary cancer faces limited oxygen and nutrient supply, it undergoes an epithelial-mesenchymal transition, which increases cancer cell motility and invasiveness. The migratory and invasive cancer cells often exert aggressive cancer development or even cancer metastasis. In this study, we investigated a novel compound, 3-acetyl-5,8-dichloro-2-((2,4-dichlorophenyl)amino)quinolin-4(1H)-one (ADQ), that showed significant suppression of wound healing and cellular invasion. This compound also inhibited anchorage-independent cell growth, multicellular tumor spheroid survival/invasion, and metalloprotease activities. The anti-proliferative effects of ADQ were mediated by inhibition of the Akt pathway. In addition, ADQ reduced the expression of mesenchymal markers of cancer cells, which was associated with the suppressed expression of Twist1. In conclusion, ADQ successfully suppressed carcinogenic activity by inhibiting the Akt signaling pathway and Twist1, which suggests that ADQ may ...
Since cancer is the leading cause of death worldwide, there is an urgent need to understand the m... more Since cancer is the leading cause of death worldwide, there is an urgent need to understand the mechanisms underlying cancer progression and the development of cancer inhibitors. Signal transducer and activator of transcription 3 (STAT3) is a major transcription factor that regulates the proliferation and survival of various cancer cells. Here, dual-specificity phosphatase 3 (DUSP3) was identified as a regulator of STAT3 based on an interaction screening performed using the protein tyrosine phosphatase library. DUSP3 interacted with the C-terminal domain of STAT3 and dephosphorylated p-Y705 of STAT3. In vitro dephosphorylation assay revealed that DUSP3 directly dephosphorylated p-STAT3. The suppressive effects of DUSP3 on STAT3 were evaluated by a decreased STAT3-specific promoter activity, which in turn reduced the expression of the downstream target genes of STAT3. In summary, DUSP3 downregulated the transcriptional activity of STAT3 via dephosphorylation at Y705 and also suppressed the migratory activity of cancer cells. This study demonstrated that DUSP3 inhibits interleukin 6 (IL-6)/STAT3 signaling and is expected to regulate cancer development. Novel functions of DUSP3 discovered in IL-6/STAT3 signaling regulation would help expand the understanding of cancer development mechanisms. [BMB Reports 2020; 53(6): 335-340]
Small-molecule inhibitors are widely used to treat a variety of inflammatory diseases. In this st... more Small-molecule inhibitors are widely used to treat a variety of inflammatory diseases. In this study, we found a novel antiinflammatory compound, 1-[(2R,4S)-2-methyl-4-(phenylamino)-1,2,3,4-tetrahydroquinolin-1-yl]prop-2-en-1-one (MPQP). It showed strong anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. These effects were exerted through the inhibition of the production of NO and pro-inflammatory cytokines, such as interleukin (IL)-6, IL-1, and tumor necrosis factor- (TNF-). Furthermore, MPQP decreased the expression levels of inducible NO synthase (iNOS) and cyclooxygenase 2 (COX-2). Additionally, it mediated the inhibition of the phosphorylation of p38, c-Jun N-terminal kinase (JNK), the inhibitor of B (IB), and their upstream kinases, IB kinase (IKK) /, mitogen-activated protein kinase kinase (MKK) 3/6, and MKK4. Furthermore, the expression of IL-1 receptor-associated kinase 1 (IRAK1) that regulates NF-B, p38, and the JNK signaling pathways, was also increased by MPQP. These results indicate that MPQP regulates the IRAK1-mediated inflammatory signaling pathways by targeting IRAK1 or its upstream factors. [
This study aimed to develop porous microspheres with a suitable porous structure and mechanical p... more This study aimed to develop porous microspheres with a suitable porous structure and mechanical property for cell delivery using a comparatively low molecular weight (MW) poly(lactide-co-glycolide) (PLGA) having a weak mechanical strength and fast degradation rate, which could be potentially used for treatment of corneal endothelial diseases. Porous microspheres of 30 kDa PLGA with different pore sizes were prepared by varying preparation conditions, and the microspheres with mean pore diameters approximately 0.5, 1, 2 and 3 times that of a single green fluorescent protein-expressing human embryonic kidney 293 cell, used as a model cell, were chosen for cell loading study. The microspheres with an average pore diameter two times greater than that of the single cell were found to be the most appropriate for efficient cell loading in the inner pore spaces, along with demonstrating a good mechanical property, injectability and biodegradability. To maximize the cell loading amount in the microspheres, the cell adhesive property of the microspheres and cell loading conditions were optimized, leading to approximately 4.2 times increase in the cell loading amount. The porous microspheres designed using the low MW PLGA hold promise as a delivery system of corneal endothelial cells for regeneration of the corneal endothelium.
Intercellular adhesion molecule-1 (ICAM-1), which is induced by tumor necrosis factor (TNF)-α, co... more Intercellular adhesion molecule-1 (ICAM-1), which is induced by tumor necrosis factor (TNF)-α, contributes to the entry of immune cells into the site of inflammation in the skin. Here, we show that protein tyrosine phosphatase non-receptor type 21 (PTPN21) negatively regulates ICAM-1 expression in human keratinocytes. PTPN21 expression was transiently induced after stimulation with TNF-α. When overexpressed, PTPN21 inhibited the expression of ICAM-1 in HaCaT cells but PTPN21 C1108S, a phosphatase activity-inactive mutant, failed to inhibit ICAM-1 expression. Nuclear factor-κB (NF-κB), a key transcription factor of ICAM-1 gene expression, was inhibited by PTPN21, but not by PTPN21 C1108S. PTPN21 directly dephosphorylated phospho-inhibitor of κB (IκB)-kinase β (IKKβ) at Ser177/181. This dephosphorylation led to the stabilization of IκBα and inhibition of NF-κB activity. Taken together, our results suggest that PTPN21 could be a valuable molecular target for regulation of inflammation ...
The spores of Lygodium japonicum (Thunb.) Sw. (L. japonicum) have been used in traditional Chines... more The spores of Lygodium japonicum (Thunb.) Sw. (L. japonicum) have been used in traditional Chinese medicine for the treatment of various inflammatory diseases. However, the molecular mechanisms underlying their anti-inflammatory effects have yet to be elucidated. In the present study, we investigated the anti-inflammatory effects of ethanol extracts of L. japonicum spores (ELJ) by measuring the production of inflammatory mediators, and explored the molecular mechanisms underlying the effects of ELJ in murine macrophages in vitro using immunoblotting analyses. At non-cytotoxic concentrations of (50-300 µg/ml), ELJ was revealed to significantly suppress the production of nitric oxide (NO) and tumor necrosis factor (TNF)-α in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophages; ELJ repressed the production of interleukin (IL)-6 only at high concentrations (≥200 µg/ml). The ELJ-mediated decrease in NO production was demonstrated to depend on the downregulation of inducible NO synthase mRNA and protein expression. Conversely, the mRNA and protein expression of cyclooxygenase-2 were not affected by ELJ. In addition, ELJ was revealed to inhibit the mRNA expression of IL-6, IL-1β, and TNF-α in LPS-stimulated RAW 264.7 macrophages. The effects of ELJ on proinflammatory mediators may have been due to the stabilization of inhibitor of κBα and the inhibition of p38 mitogen-activated protein kinase (MAPK). These results suggested that ELJ may suppress LPS-induced inflammatory responses in murine macrophages in vitro, through the negative regulation of p38 MAPK and nuclear factor (NF)-κB. Therefore, ELJ may have potential as a novel candidate for the development of therapeutic strategies aimed at alleviating inflammation.
Spilanthes acmella Murr. (S. acmella) has been used traditionally in India and Sri Lanka to treat... more Spilanthes acmella Murr. (S. acmella) has been used traditionally in India and Sri Lanka to treat various inflammatory diseases. However, the anti‑inflammatory effects and underlying mechanism of action of S. acmella are unclear. The present study assessed the anti‑inflammatory properties of methanol extracts of S. acmella (MSA) in murine macrophages. MSA (≤300 µg/ml) inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)‑stimulated RAW 264.7 macrophages through transcriptional inhibition of inducible nitric oxide synthase expression in a dose‑dependent manner. Furthermore, the LPS‑induced prostaglandin E2 production and cyclooxygenase‑2 expression were inhibited by MSA (300 µg/ml). MSA treatment inhibited interleukin (IL)‑6 production and decreased the mRNA expression levels of proinflammatory cytokines, including IL‑6 and IL‑1β. In addition, no significant inhibition in tumor necrosis factor‑α production was detected. Inhibitory effects of MSA on the production of infl...
The rhizome of Anemarrhena asphodeloides Bunge (A. asphodeloides) has been used as a traditional ... more The rhizome of Anemarrhena asphodeloides Bunge (A. asphodeloides) has been used as a traditional East Asian medicine for the treatment of various types of inflammatory disease. However, to the best of our knowledge, there have been no systemic studies regarding the molecular mechanisms of action of the A. asphodeloides rhizome anti-inflammatory effects. The aim of the present study was to elucidate the anti-inflammatory effects and underlying mechanism of action of ethanol extracts of the rhizome of A. asphodeloides (EAA) in murine macrophages. Non-cytotoxic concentrations of EAA (10-100 µg/ml) significantly decreased the production of NO and interleukin (IL)-6 in lipopolysaccharide (LPS)-stimulated macrophages, while the production of tumor necrosis factor-α was not regulated by EAA. EAA-mediated reduction of nitric oxide (NO) was due to reduced expression levels of inducible NO synthase (iNOS). Furthermore, protein expression levels of LPS-induced cyclooxygenase-2, another inflammatory enzyme, were alleviated in the presence of EAA. EAA-mediated reduction of those proinflammatory mediators was due to inhibition of nuclear factor-κB (NF-κB) and activator protein 1 transcriptional activities followed by the stabilization of inhibitor of κ Bα and inhibition of p38, respectively. These results indicate that EAA suppresses LPS-induced inflammatory responses by negatively regulating p38 and NF-κB, indicating that EAA is a candidate treatment for alleviating inflammation.
Mitogen-activated protein kinases (MAPKs) are involved in a variety of intracellular events such ... more Mitogen-activated protein kinases (MAPKs) are involved in a variety of intracellular events such as gene expression, cell proliferation, and programmed cell death. MAPKs are activated by dual phosphorylation on threonine and tyrosine residues through sequential activation of protein kinases. Recent studies have shown that the protein kinases involved in MAPK signal transductions might be organized into signaling complexes by scaffold proteins. These scaffold proteins are essential regulators that function by assembling the relevant molecular components in mammalian cells. In this study, we report that dual-specificity phosphatase 22 (DUSP22), a member of the protein tyrosine phosphatase family, acts as a distinct scaffold protein in c-Jun N-terminal kinase (JNK) signaling. DUSP22 increased the phosphorylation in the activation loop of JNK regardless of its phosphatase activity but had no effect on phosphorylation levels of ERK and p38 in mammalian cells. Furthermore, DUSP22 selectiv...
International journal of molecular medicine, Jan 21, 2016
Thunbergia alata (Acanthaceae) has been used traditionally to treat various inflammatory diseases... more Thunbergia alata (Acanthaceae) has been used traditionally to treat various inflammatory diseases such as fever, cough and diarrhea in East African countries including Uganda and Kenya. However, systemic studies elucidating the anti-inflammatory effects and precise mechanisms of action of T. alata have not been conducted, to the best of our knowledge. To address these concerns, we explored the anti-inflammatory effects of a methanol extract of T. alata (MTA) in macrophages. Non-cytotoxic concentrations of MTA (≤300 µg/ml) inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)‑stimulated RAW 264.7 macrophages by transcriptional regulation of inducible NO synthase in a dose-dependent manner. The expression of cyclooxygenase-2, the enzyme responsible for the production of prostaglandin E2, was unchanged by MTA at the mRNA and protein levels. MTA treatment inhibited interleukin (IL)-6 production and decreased the mRNA expression of pro‑inflammatory cytokines, including IL-6 ...
Crataeva nurvala Buch. Ham. is an important medicinal plant in India, and its extracts and compon... more Crataeva nurvala Buch. Ham. is an important medicinal plant in India, and its extracts and components were used to treat various inflammatory diseases, such as urinary tract infection, rheumatoid arthritis, and colitis. However, no systemic studies about anti-inflammatory effects of Crataeva nurvala Buch. Ham. and its underlying mechanisms of action have been reported. This study aimed to explore the anti-inflammatory effects of ethanol extracts of Crataeva nurvala Buch. Ham. (ECN). The non-cytotoxic and maximal effective concentration of ECN was determined by measuring the formation of formazan from water-soluble tetrazolium salt in living cells. The inhibitory effect of ECN on nitric oxide (NO) synthesis was measured using Griess reagent, and Enzyme-linked immunosorbent assay (ELISA) was used to measure secreted tumor necrosis factor (TNF)-α and interleukin (IL)-6 protein levels. Furthermore, reverse transcription polymerase chain reaction (RT-PCR) and Western blotting analysis were used to assess the mRNA and protein expression of each inflammatory mediator or relating signaling protein, respectively. A non-cytotoxic concentration of ECN (≤200 μg/ml) significantly reduced the production of NO and IL-6, but not TNF-α, in lipopolysaccharides (LPS)-stimulated RAW 264.7 macrophages. Decreased production of NO by ECN was correlated with reduced expression of iNOS at the mRNA and protein levels. However, cyclooxygenase (COX)-2 expressions at mRNA and protein level were not regulated by ECN. The mRNA expression of IL-6 and IL-1β, but not TNF-α, was also inhibited by ECN treatment in LPS-stimulated RAW 264.7 macrophages. Reduced production of inflammatory mediators by ECN was followed by decreased activity of mitogen-activated protein kinases (MAPKs), especially extracellular signal-regulated kinase (ERK), but not nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). These results indicate that ECN inhibits LPS-induced inflammatory responses via negative regulation of ERK in murine macrophages, suggesting that ECN is a candidate for alleviating severe inflammation.
Myrmecodia platytyrea Becc., a member of the Rubiaceae family, is found throughout Southeast Asia... more Myrmecodia platytyrea Becc., a member of the Rubiaceae family, is found throughout Southeast Asia and has been traditionally used to treat cancer. However, there is limited pharmacological information on this plant. We investigated the anticancer effects of the methanol extract of Myrmecodia platytyrea Becc. leaves (MMPL) and determined the molecular mechanisms underlying the effects of MMPL on metastasis in human hepatocellular carcinoma (HCC) cells. MMPL dose-dependently inhibited cell migration and invasion in SK-Hep1 and Huh7 cells. In addition, MMPL strongly suppressed the enzymatic activity of matrix metalloproteinases (MMP-2 and MMP-9). Diminished telomerase activity by MMPL resulted in the suppression of both telomerase activity and telomerase-associated gene expression. The levels of urokinase-type plasminogen activator receptor (uPAR) expression as well as the phosphorylation levels of signal transducer and activator of transcription 3 (STAT3) and extracellular signal-regulated kinase (ERK) were also attenuated by MMPL. The above results collectively suggest that MMPL has anticancer effects in HCC and that MMPL can serve as an effective therapeutic agent for treating human liver cancer. Semut. This genus is native to Southeast Asia, but it can also be found in Myanmar, Indochina, and northern Queensland in Australia (13). Myrmecodia plants contain a highly specialized tuber and modified stems, which are used by ant colonies (14). Myrmecodia species have traditionally been used to treat diseases such as ulcers, tumors, cancer, hepatitis, and coronary artery disease (15). In pharmacological studies, Myrmecodia pendens and tuberose are both considered to be potential anticancer agents. Water extracts of Myrmecodia pendens have been shown to inhibit HeLa and MCM-B2 cancer cell growth (16). Five flavonoids of Myrmecodia pendens, kaempferol, luteolin, rutin, quercetin, and apigenin, were identified and quantified, and
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Papers by Ba Reum Kim