• Journal of Microbiology and Biotechnology
• /
• 제32권5호
• /
• pp.645-656
• /
• 2022

Gossypol, a natural phenolic aldehyde present in cotton plants, was originally used as a means of contraception, but is currently being studied for its anti-proliferative and anti-metastatic effects on various cancers. However, the intracellular mechanism of action regarding the effects of gossypol on pancreatic cancer cells remains unclear. Here, we investigated the anti-cancer effects of gossypol on human pancreatic cancer cells (BxPC-3 and MIA PaCa-2). Cell counting kit-8 assays, annexin V/propidium iodide staining assays, and transmission electron microscopy showed that gossypol induced apoptotic cell death and apoptotic body formation in both cell lines. RNA sequencing analysis also showed that gossypol increased the mRNA levels of CCAAT/enhancer-binding protein homologous protein (CHOP) and activating transcription factor 3 (ATF3) in pancreatic cancer cell lines. In addition, gossypol facilitated the cleavage of caspase-3 via protein kinase RNA-like ER kinase (PERK), CHOP, and Bax/Bcl-2 upregulation in both cells, whereas the upregulation of ATF was limited to BxPC-3 cells. Finally, a three-dimensional culture experiment confirmed the successful suppression of cancer cell spheroids via gossypol treatment. Taken together, our data suggest that gossypol may trigger apoptosis in pancreatic cancer cells via the PERK-CHOP signaling pathway. These findings propose a promising therapeutic approach to pancreatic cancer treatment using gossypol.

• 대한의생명과학회지
• /
• 제27권4호
• /
• pp.223-230
• /
• 2021

Tumor necrosis factor alpha (TNF-α) is a principal regulator of inflammation and immunity. The proinflammatory properties of TNF-α can be attributed to its ability to activate the enzyme cytosolic phospholipase A₂ (cPLA₂), which generates potent inflammatory lipid mediators, eicosanoids. L-glutamine (Gln) plays physiologically important roles in various metabolic processes. We have reported that Gln has a potent anti-inflammatory activity via rapid upregulation of mitogen-activated protein kinases (MAPKs) phosphatase (MKP)-1, which preferentially dephosphorylates the key proinflammatory enzymes, p38 MAPK and cytosolic phospholipase A₂ (cPLA₂). In this study, we have investigated whether Gln could inhibit TNF-α-induced cPLA₂ activation. Gln inhibited TNF-α-induced increases in cPLA₂ phosphorylation in the lungs and blood levels of the cPLA₂ metabolites, leukotrine B4 (LTB4) (lipoxygenase metabolite) and prostaglandin E2 (PGE2) (cyclooxygenase metabolite). TNF-α increased p38 and cPLA₂ phosphorylation and blood levels of LTB4 and PGE2, which were blocked by the p38 inhibitor SB202190. Gln inhibited TNF-α-induced p38 and cPLA₂ phosphorylation and production of the cPLA₂ metabolites. Such inhibitory activity of Gln was no longer observed in MKP-1 small interfering RNA-pretreated animals. Our data indicate that Gln inhibited TNF-α-induced cPLA₂ phosphorylation through MKP-1 induction/p38 inhibition, and suggest that the utility of Gln in inflammatory diseases in which TNF-α plays a major role in their pathogenesis.

• 대한본초학회지
• /
• 제28권6호
• /
• pp.145-153
• /
• 2013

Objectives : Neuroinflammation is characterized by microglial activation and the expression of major inflammatory mediators. The present study investigated the inhibitory effect of ginsenoside Rg1 ($GRg_1$), a principle active ingredient in Panax ginseng, on pro-inflammatory cytokines and microglial activation induced by systemic lipopolysaccharide (LPS) treatment in the mouse brain tissue. Methods : Varying doses of $GRg_1$ was orally administered (10, 20, and 30 mg/kg) 1 h before the LPS injection (3 mg/kg, intraperitoneally). The mRNA expression of pro-inflammatory cytokines in the brain tissue was measured using the quantitative real-time PCR method at 4 h after the LPS injection, Microglial activation was evaluated using western blotting and immunohistochemistry against ionized calcium binding adaptor molecule 1 (Iba1) in the brain tissue. Cyclooxigenase-2 (COX-2) expressions also observed using western blotting and immunohistochemistry at 4 h after the LPS injection, In addition, double-immunofluorescent labeling of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and COX-2 with microglia and neurons was processed in the brain tissue. Results : $GRg_1$ (30 mg/kg) significantly attenuated the upregulation of TNF-${\alpha}$, interleukin (IL)-$1{\beta}$ and IL-6 mRNA in the brain tissue at 4 h after LPS injection. Morphological activation and Iba1 protein expression of microglia induced by systemic LPS injection were reduced by the $GRg_1$ (30 mg/kg) treatment. Upregulation of COX-2 protein expression in the brain tissue was also attenuated by the $GRg_1$ (30 mg/kg) treatment. Conclusion : The results suggest that $GRg_1$ is effective in the early stage of neuroinflammation which causes neurodegenerative diseases.

• Biomolecules & Therapeutics
• /
• 제30권5호
• /
• pp.465-472
• /
• 2022

Melanoma is one of the most aggressive skin cancers. Hypoxia contributes to the aggressiveness of melanoma by promoting cancer growth and metastasis. Upregulation of cyclin D1 can promote uncontrolled cell proliferation in melanoma, whereas stimulation of cytotoxic T cell activity can inhibit it. Epithelial mesenchymal transition (EMT) plays a critical role in melanoma metastasis. Hypoxia-inducible factor-1α (HIF-1α) is a main transcriptional mediator that regulates many genes related to hypoxia. CoCl₂ is one of the most commonly used hypoxia-mimetic chemicals in cell culture. In this study, inhibitory effects of IDF-11774, an inhibitor of HIF-1α, on melanoma growth and metastasis were examined using cultured B16F10 mouse melanoma cells and nude mice transplanted with B16F10 melanoma cells in the presence or absence of CoCl₂-induced hypoxia. IDF-11774 reduced HIF-1α upregulation and cell survival, but increased cytotoxicity of cultured melanoma cells under CoCl₂-induced hypoxia. IDF-11774 also reduced tumor size and local invasion of B16F10 melanoma in nude mice along with HIF-1α downregulation. Expression levels of cyclin D1 in melanoma were increased by CoCl₂ but decreased by IDF-11774. Apoptosis of melanoma cells and infiltration of cytotoxic T cells were increased in melanoma after treatment with IDF-11774. EMT was stimulated by CoCl₂, but restored by IDF11774. Overall, IDF-11774 inhibited the growth and metastasis of B16F10 melanoma via HIF-1α downregulation. The growth of B16F10 melanoma was inhibited by cyclin D1 downregulation and cytotoxic T cell stimulation. Metastasis of B16F10 melanoma was inhibited by EMT suppression.

• Biomolecules & Therapeutics
• /
• 제7권4호
• /
• pp.335-341
• /
• 1999

Antidiabetic activity and mechanism of Supungsungihyan(SPSGH) were examined in db/db mice, which is a spontaneously hyperglycemic, hyperinsulinemic and obese animal model. SPSGH and acarbose were administered orally for 4 weeks. Fasting and non-fasting serum glucose, glycated hemoglobin and trig-lyceride of SPSGH treated group were all reduced when compared with those of db/db control group. At 12th week after birth, SPSGH increased an insulin secretion although statistic significance was not seen. Total activities of sucrose, maltase and lactase in SPSGH treated group were not significantly different from those in db/db control. On the other hand, sucrase and maltase activities in acarbose treated groups were increased. Effect of SPSGH on mRNA expression of glucose transporter(GLUT-4) was also examined by RT-PCR and in vitro transcription with co-amplification of rat $\beta$-actin gene as an internal standard. Muscular GLUT-4 mRNA expression in SPSGH treated group was increased significantly. These results may suggest that SPSGH lowered blood glucose ascribing to upregulation of muscular GLUT-4 mRNA expression.

• 한국미생물학회:학술대회논문집
• /
• 한국미생물학회 2005년도 International Meeting of the Microbiological Society of Korea
• /
• pp.214.3-214
• /
• 2005

• Biomolecules & Therapeutics
• /
• 제18권4호
• /
• pp.411-419
• /
• 2010

Korean mistletoe has a variety of biological effects, such as immunoadjuvant activities. This study investigates the effects of Korean mistletoe lectin (Viscum album L. var. coloratum agglutinin, VCA) on human T lymphocytes to determine whether VCA acts as an immunomodulator. Purified human T-lymphocytes were cultured with VCA and RNA from each point was analyzed using Affymetrix human genome chips containing 22,500 probe sets which represents more than 18,000 transcripts derived from 14,500 human genes. As a result, there was a striking upregulation of genes coding for chemokines. Seventeen genes out of 50 coding for proteins with chemokine activity were upregulated including CXCL9 and IL-8 which are related to the treatment of cancer. In addition, 28 cytokine genes were upregulated including IL-1, IL-6, IL-8, IFN-$\gamma$, and TNF-$\alpha$. Taken together, the data suggest that Korean mistletoe lectin, in parallel with European mistletoe, has an ability to modulate human T cell function.

• BMB Reports
• /
• 제31권4호
• /
• pp.339-344
• /
• 1998

The plant flavonoids, including apigenin which is found in especially high concentrations in edible plants, are reported to protect against chronic diseases including several types of cancer. We observed that apigenin inhibited not only the growth of human melanoma cell line SK-MEL 28 but also the telomerase activity. We also noted the telomerase activity inhibition by genistein, a tyrosine kinase inhibitor found in soybean, which suggests that the telomerase activity of SK-MEL 28 cells may be regulated by the protein phosphorylation. Furthermore, we observed that apigenin induced SK-MEL 28 cell apoptosis with p53 upregulation. Taken together, our results indicate that apigenin plays a role as an antimelanoma component in edible plants.

• BMB Reports
• /
• 제33권4호
• /
• pp.308-311
• /
• 2000

The interrelationship between the differentiation and expression of mRNA for transferrin in the HL-60 leukemia cell line was studied. Transferrin mRNA was expressed in HL-60 leukemia cells and the amount was 50% of that in the positive control cell line, HepG-2 cells. The expression of $T_f$ mRNA in HL-60 cells was not regulated by IL-1, IL-6 and $TNF-{\alpha}$, respectively. The expression of $T_f$ mRNA in the differentiated cells into a granulocyte lineage by DMSO, or all-trans RA, was up-regulated (160-170% of control cells); whereas, the expression was not regulated in the differentiated cells into a macrophage lineage by PMA. These results suggest that the differentiation to a granulocyte lineage of HL-60 leukemia cells appear to be related with the upregulation of transferrin mRNA expression.

• The Korean Journal of Physiology and Pharmacology
• /
• 제5권2호
• /
• pp.183-188
• /
• 2001

To elucidate antidiabetic effect and mechanism(s) of acarbose in a polygenic spontaneous hyperglycemic and hyperinsulinemic diabetic animal model, $KKA^y$ mice, acarbose was administered orally for 4 weeks and effects on body weight, plasma glucose and insulin levels, genetic expressions of intestinal sucrase-isomaltase (SI), sodium-glucose cotransporter (sGLT1) and glucose transporter in quadriceps muscle (GLUT4) were examined in this study. Although no differences in body weight were detected between control and acarbose-treated groups, plasma glucose level in acarbose-treated group was markedly reduced as compared to the control. In the mechanism study, acarbose downregulated the SI and SGLT1 gene expressions, and upregulated the GLUT4 mRNA and protein expressions when compared to the control group. In conclusion, the data obtained strongly implicate that acarbose can prevent the hyperglycemia in $KKA^y$ mice possibly through blocking intestinal glucose absorption by downregulations of SI and sGLT1 mRNA expressions, and upregulation of skeletal muscle GLUT4 mRNA and protein expressions.