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Extract of Ranunculus sceleratus Reduced Adipogenesis by Inhibiting AMPK Pathway in 3T3-L1 Preadipocytes (3T3-L1 전구지방세포에서 개구리자리(Ranunculus sceleratus) 추출물의 AMPK 신호전달을 통한 지방생성 억제 효과)

  • Kim, Yae-Ji;Cho, Sung-Pil;Lee, Hui-Ju;Hong, Geum-Lan;Kim, Kyung-Hyun;Ryu, Si-Yun;Jung, Ju-Young
    • Journal of Korean Medicine for Obesity Research
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    • v.22 no.1
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    • pp.30-37
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    • 2022
  • Objectives: Adipogenesis is the process by which pre-adipocytes are differentiated into adipocytes. It also plays an important role in adipocyte formation and lipid accumulation. Ranunculus sceleratus (R. sceleratus) extracts are used for the treatment of various diseases such as hepatitis, jaundice, and tuberous lymphadenitis in oriental medicine. However, its effect on adipogenesis has not yet been studied. In this study, we investigated the effects of R. sceleratus on adipogenesis in 3T3-L1 cells. Methods: Cells were treated with 50, 100, and 200 ㎍/ml of R. sceleratus and cell viability was evaluated. To differentiate the 3T3-L1 preadipocytes, a 3-isobutyl-1-methylxanthine, dexamethasone, and insulin (MDI) solution were used. The accumulation of lipid droplets was determined by Oil Red O staining. The expression levels of adipogenesis-related proteins were also determined. Results: MDI solution differentiated the preadipocytes into adipocytes and accumulation of lipids was observed in the differentiated 3T3-L1 cells. Interestingly, the amount of lipid droplets was reduced after R. sceleratus treatment. In addition, the expression levels of key adipogenic transcription factors, such as CCAAT/enhancer-binding proteins-𝛼 (C/EBP-𝛼) and peroxisome proliferator-activated receptors-𝛾 (PPAR-𝛾) were also reduced after R. sceleratus treatment. Furthermore, R. sceleratus increased AMP-activated kinase (AMPK) phosphorylation and decreased sterol regulatory element-binding protein-1 expression. Conclusions: Our results showed that R. sceleratus reduced preadipocyte differentiation by inhibiting C/EBP-𝛼 and PPAR-𝛾 levels via the AMPK pathway. Therefore, we suggest that R. sceleratus may be potentially used as an anti-adipogenic agent.

Diverse Mechanisms of Relaxin's Action in the Regulation of Smooth Muscles and Extracellular Matrix of Vasculature and Fibrosis (혈관과 섬유증의 평활근 및 세포외기질 조절에 대한 릴랙신의 다양한 작용기전)

  • Min, Gyesik
    • Journal of Life Science
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    • v.32 no.2
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    • pp.175-188
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    • 2022
  • Relaxin has been demonstrated to have regulatory functions on both the smooth muscle and extracellular matrix (ECM) of blood vessels and fibrotic organs. The diverse mechanisms by which relaxin acts on small resistance arteries and fibrotic organs, including the bladder, are reviewed here. Relaxin induces vasodilation by inhibiting the contractility of vascular smooth muscles and by increasing the passive compliance of vessel walls through the reduction of ECM components, such as collagen. The primary cellular mechanism whereby relaxin induces arterial vasodilation is mediated by the endothelium-dependent production of nitric oxide (NO) through the activation of RXFP1/PI3K, Akt phosphorylation, and eNOS. In addition, relaxin triggers different alternative pathways to enhance the vasodilation of renal and mesenteric arteries. In small renal arteries, relaxin stimulates the activation of the endothelial MMPs and EtB receptors and the production of VEGF and PlGF to inhibit myogenic contractility and collagen deposition, thereby bringing about vasodilation. Conversely, in small mesenteric arteries, relaxin augments bradykinin (BK)-evoked relaxation in a time-dependent manner. Whereas the rapid enhancement of the BK-mediated relaxation is dependent on IKCa channels and subsequent EDH induction, the sustained relaxation due to BK depends on COX activation and PGI2. The anti-fibrotic effects of relaxin are mediated by inhibiting the invasion of inflammatory immune cells, the endothelial-to-mesenchymal transition (EndMT), and the differentiation and activation of myofibroblasts. Relaxin also activates the NOS/NO/cGMP/PKG-1 pathways in myofibroblasts to suppress the TGF-β1-induced activation of ERK1/2 and Smad2/3 signaling and deposition of ECM collagen.

Metabolic Signaling by Adipose Tissue Hormones in Obesity (비만에서 adipose tissue 호르몬에 의한 metabolic signaling)

  • Younghoon Jang
    • Journal of Life Science
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    • v.33 no.3
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    • pp.287-294
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    • 2023
  • Healthy adipose tissue is critical for preventing obesity by maintaining metabolic homeostasis. Adipose tissue plays an important role in energy homeostasis through glucose and lipid metabolism. Depending on nutritional status, adipose tissue expands to store lipids or can be consumed by lipolysis. The role of adipose tissue as an endocrine organ is emerging, and many studies have reported that there are various adipose tissue hormones that communicate with other organs and tissues through metabolic signaling. For example, leptin, a representative peptide hormone secreted from adipose tissues (adipokine), circulates and targets the central nervous system of the brain for appetite regression. Furthermore, adipocytes secrete inflammatory cytokines to target immune cells in adipose tissues. Not surprisingly, adipocytes can secrete fatty acid-derived hormones (lipokine) that bind to their specific receptors for paracrine and endocrine action. To understand organ crosstalk by adipose tissue hor- mones, specific metabolic signaling in adipocytes and other communicating cells should be defined. The dysfunction of metabolic signaling in adipocytes occurs in unhealthy adipose tissue in overweight and obese conditions. Therapy targeting novel adipose metabolic signaling could potentially lead to the development of an effective anti-obesity drug. This review summarizes the latest updates on adipose tissue hormone and metabolic signaling in terms of obesity and metabolic diseases.

Comprehensive analysis of miRNAs, lncRNAs and mRNAs profiles in backfat tissue between Daweizi and Yorkshire pigs

  • Chen Chen;Yitong Chang;Yuan Deng;Qingming Cui;Yingying Liu;Huali Li;Huibo Ren;Ji Zhu;Qi Liu;Yinglin Peng
    • Animal Bioscience
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    • v.36 no.3
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    • pp.404-416
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    • 2023
  • Objective: Daweizi (DWZ) is a famous indigenous pig breed in China and characterized by tender meat and high fat percentage. However, the expression profiles and functions of transcripts in DWZ pigs is still in infancy. The object of this study was to depict the transcript profiles in DWZ pigs and screen the potential pathway influence adipogenesis and fat deposition, Methods: Histological analysis of backfat tissue was firstly performed between DWZ and lean-type Yorkshire pigs, and then RNA sequencing technology was utilized to explore miRNAs, lncRNAs and mRNAs profiles in backfat tissue. 18 differentially expressed (DE) transcripts were randomly selected for quantitative real-time polymerase chain reaction (QPCR) to validate the reliability of the sequencing results. Finally, gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis were conducted to investigate the potential pathways influence adipocyte differentiation, adipogenesis and lipid metabolism, and a schematic model was further proposed. Results: A total of 1,625 differentially expressed transcripts were identified in DWZ pigs, including 27 upregulated and 45 downregulated miRNAs, 64 upregulated and 119 down-regulated lncRNA, 814 upregulated and 556 downregulated mRNAs. QPCR analysis exhibited strong consistency with the sequencing data. GO and KEGG analysis elucidated that the differentially expressed transcripts were mainly associated with cell growth and death, signal transduction, peroxisome proliferator-activated receptors (PPAR), AMP-activated protein kinase (AMPK), PI3K-Akt, adipocytokine and foxo signaling pathways, all of which are strongly involved in cell development, lipid metabolism and adipogenesis. Further analysis indicated that the BGIR9823_87926/miR-194a-5p/AQP7 network may be effective in the process of adipocyte differentiation or adipogenesis. Conclusion: Our study provides comprehensive insights into the regulatory network of backfat deposition and lipid metabolism in pigs from the point of view of miRNAs, lncRNAs and mRNAs.

Comparison and evaluation of 89Zr-labeled trastuzumab and Thio-trastuzumab : a potential immuno-PET probe for HER2-positive carcinomas

  • Un Chol Shin;Seoku Bae;Suk-man Kim;Min-Woo Lee;Han Sang Jin;Hyun Park;Kyo Chul Lee;Jung Young Kim;Ji Woong Lee
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.7 no.2
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    • pp.105-111
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    • 2021
  • 89Zr is a positron-emitting radioisotope, which has known as well-suited radioisotope for use in a monoclonal antibody-based imaging agent for immuno-PET. The purpose of this study was to quantitatively evaluate the diagnostic ability of general trastuzumab and thio-trastuzumab as HER2 positive receptors based on Df hexadentate iron chelator. Desferrioxamine-p-SCN (Df-Bz-NCS) and desferroixamine-maleimide (Df-Mal) were purchased from Macrocyclics (Dallas, TX, USA). The trastuzumab was purchased from Roche (Schweiz), and thio-trastuzumab was obtained from professor Hyo-Jeong Hong group (Kangwon National University). The radioisotope 89Zr was produced by domestic purification system and KIRAMS using medical cyclotron (50 MeV, Scantronix). The conjugates of Df-trastuzumab and Df-thio-trastuzumab were prepared with Df-Bz-NCS and Df-Mal under basic aqueous solution (pH 8-9) at room temperature, respectively. The conjugates purified by PD-10 column were mixed with dried 89Zr chloride. 89Zr-labeled conjugates were purified and concentrated by Amicon ultra centrifugal filter. The preparation step and time of 89Zr-labeled conjugates was shorted as 4 steps within 2 hours. 89Zr-labeled conjugates showed the highly radiochemical purity of over 98%, and were very stable until 7 days by the analysis of radio-ITLC method. Each radio-labeled conjugates were also exhibited the highly stability in both PBS buffer and mouse serum. Immuno-PET imaging of 89Zr-labeled conjugates in mice bearing gastric cancer xenograft tumors with HER2 expression showed high tumor uptake in the NCI-N87 HER2-expressing. However, 89Zr-Df-Mal-thio-trastuzumab showed a relatively lower tumor-to-background ratio than 89Zr-Df-Bz-trastuzumab, as well as whole-body distribution. In the results, 89Zr-Df-Bz-trastuzumab was evaluated to have a relatively higher HER2 diagnostic ability than 89Zr-Df-Mal-thio-trastuzumab.

The Effect of Ampelopsis japonica (Thunb.) Makino on Osteoclastogenesis and Expression of Osteoclast-Related Gene (백렴(白蘞)의 파골세포 분화 및 관련 유전자 발현 억제에 미치는 영향)

  • Hongsik Kim;Sumin Lee;Minsun Kim;Jae-Hyun Kim;Yejin Kang;Seoung Jun Kwon;Youngwoo Nam;Seungwoo Yoo;Hong-Seok Choi;SeonJin Huh;Youngjoo Sohn;Hyuk-Sang Jung
    • The Korea Journal of Herbology
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    • v.38 no.5
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    • pp.9-19
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    • 2023
  • Objectives : Osteoporosis is a systemic skeletal disorder characterized by reduced bone mineral density and increased risk of fractures. Bisphosphonates and selective estrogen receptors, which are bone resorption inhibitors that are currently widely used as osteoporosis treatments, show serious side effects when administered for a long time. Research on bone resorption inhibitors that complement the problems of existing treatments is needed. The purpose of this study was to investigate the effect of inhibiting osteoclast differentiation and activity on the tuberous root of Ampelopsis japonica (Thunb.) Makino (AM). Methods : After extracting AM using distilled water and ethanol, the inhibitory effects of the two solvents on osteoclast differentiation were compared using the RANKL-induced in vitro experimental model and the TRAP assay kit. The impact of AM on bone resorption was investigated through the pit formation assay, and its effect on F-actin formation was assessed through fluorescent staining. Additionally, protein and mRNA expression levels of osteoclast differentiation markers (NFATc1, c-Fos, TRAP and ATP6v0d2) and resorption markers (MMP-9, CTK, and CA2) were analyzed via western blot and RT-PCR. Results : AM treatment significantly decreased the number of TRAP-positive cells and pit formation area. Furthermore, AM suppressed both the protein and mRNA expression of NFATc1 and c-Fos, key transcription factors involved in osteoclast differentiation and it downregulated the expression of osteoclast-associated genes such as TRAP, CTK, MMP-9, CA2, and ATP6v0d2. Conclusions : These results suggest that AM can inhibit bone resorption and osteoclast differentiation, indicating its potential for use in the treatment and prevention of osteoporosis.

Mutations of Constitutive Activation and Mutations That Impair Signal Transduction Modulate the Agonist-stimulated Internalization of the Lutropin/choriogonadotropin Receptor

  • Park, J.J.;Kim, M.S.;Lee, Y.Y.;H.Y. Kang;Y.M. Chang;Yoon, J.T.;K.S. Min
    • Proceedings of the Korean Society of Developmental Biology Conference
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    • 2003.10a
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    • pp.83-83
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    • 2003
  • The lutropin/choriogonadotropin receptor (LHR) is a member of the rhodopsin-like subfamily of G protein coupled receptor (GPCRs), that has been shown to mediate the internalization of its two naturally occurring agonist, lutropin and choriogonadotropin (CG). The clustered agonist-receptor complex is internalized by a dynamin-dependent pathway and traverses the endosomal compartment without agonist dissociation Dissociation of the agonist-receptor complex occurs in the lysosomes, where both the agonist and receptor are degrade. Recently, constitutively activating mutations of the receptor have been identified that are associated with familial male-precocious puberty (FMPP). A FMPP is a form of sexual precocious puberty in boys in which testosterone levels are elevated independent of changes in luteinizing hormone-releasing hormone and serum luteinizing hormone levels, We have now analyzed two naturally occurring, constitutively active mutants of the human LHR. These mutations were introduced into the rat LHR (rLHR) and are designated L435R and D556Y. Cells expressing rLHR-D556Y bind human choriogonadotropin (hCG) with normal affinity, exhibit a 25-fold increase in basal cAMP and respond to hCG with a normal increase in cAMP accumulation. Cells expressing rLHR-L435R also bind hCG with normal affinity, exhibit a 47-fold increase in basal cAMP, and do not respond to hCG with a further increase in cAMP accumulation. This mutation enhances the internalization of the free and agonist-occupied receptors ~2- and ~17- fold, respectively We conclude that the state of activation of the rLHR can modulate its basal and/or agonist-stimulated internalization. Since the internalization of hCG is involved in the termination of hCG actions, we suggest that the lack of responsiveness detected in cells expressing rLHR-L435R is due to the fast rate of internalization of the bound hCG. The finding that membranes expressing rLHR-L435R respond to hCG with an increase in adenylyl cyclase activity supports this suggestion. Autonomous Leydig cell activity in FMPP is caused by a constitutively activating LH/CGR.

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Function of 27-Hydroxycholesterol in Various Tissues and Diseases (다양한 조직 및 질병에서 27-하이드록시콜레스테롤의 역할 및 기전 고찰)

  • Shim, Wan-Seog;Lee, Chanhee;Azamov, Bakhovuddin;Kim, Koanhoi;Lee, Dongjun;Song, Parkyong
    • Journal of Life Science
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    • v.32 no.3
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    • pp.256-262
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    • 2022
  • Oxysterols are oxygenated metabolites of cholesterol generated by serial enzymatic reactions during bile acid synthesis. Similar to cholesterol, oxysterols move rapidly to the intracellular region and modulate various cellular processes, such as immune cell responses, lipid metabolism, and cholesterol homeostasis. Different nuclear transcription factors, such as glucocorticoid, estrogen, and liver X receptors, can be modulated by oxysterols in multiple tissues. The most abundant oxysterol, 27-hydroxycholesterol (27-OHC), is a well-known selective modulator that can either activate or suppress estrogen receptor activity in a tissue-specific manner. The contribution of 27-OHC in atherosclerosis development is apparent because a large amount of it is found in atherosclerotic plaques, accelerating the transformation of macrophages into foam cells that uptake extracellular modified lipids. According to previous studies, however, there are opposing opinions about how 27-OHC affects lipid and cholesterol metabolism in metabolic organs, including the liver and adipose tissue. In particular, the effects of 27-OHC on lipid metabolism are entirely different between in vitro and in vivo conditions, suggesting that understanding the physiology of this oxysterol requires a sophisticated approach. This review summarizes the potential effects of 27-OHC in atherosclerosis and metabolic syndromes with a special discussion of its role in metabolic tissues.

Electrochemical Mass Transport Control in Biomimetic Solid-State Nanopores (생체모사형 나노포어를 활용한 전기화학 기반 물질전달 조절 시스템)

  • Soongyu Han;Yerin Bang;Joon-Hwa Lee;Seung-Ryong Kwon
    • Journal of the Korean Electrochemical Society
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    • v.26 no.4
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    • pp.43-55
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    • 2023
  • Mass transport through nanoporous structures such as nanopores or nanochannels has fundamental electrochemical implications and many potential applications as well. These structures can be particularly useful for water treatment, energy conversion, biosensing, and controlled delivery of substances. Earlier research focused on creating nanopores with diameters ranging from tens to hundreds of nanometers that can selectively transport cationic or anionic charged species. However, recent studies have shown that nanopores with diameters of a few nanometers or even less can achieve more complex and versatile transport control. For example, nanopores that mimic biological channels can be functionalized with specific receptors to detect viruses, small molecules, and even ions, or can be made hydrophobic and responsive to external stimuli, such as light and electric field, to act as efficient valves. This review summarizes the latest developments in nanopore-based systems that can control mass transport based on the size of the nanopores (e.g., length, diameter, and shape) and the physical/chemical properties of their inner surfaces. It also provides some examples of practical applications of these systems.

Cordycepin Inhibits LPS-induced Cell Migration and Invasion in Human Colorectal Carcinoma HCT116 cells through Down-regulation of Prostaglandin E2-EP4 Receptor (LPS 유도된 HCT116 인간 대장암세포에서 cordycepin의 prostaglandin E2-EP4 receptor 감소 조절을 통한 세포의 이동과 전이 억제 효과)

  • Jung Eun Kim;Bo-Ram Kim;Su Hui Seong;Jin-Ho Kim;Ha-Nul Lee;Chan Seo;Ji Min Jung;Su A Im;Kyung-Min Choi;Jin-Woo Jeong
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2023.04a
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    • pp.50-50
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    • 2023
  • Prostaglandin E2(PGE2), a major product of cyclooxygenase-2 (COX-2), plays an important role in the carcinogenesis of many solid tumors, including colorectal cancer. Because PGE2 functions by signaling through PGE2 receptors (Eps), which regulate tumor cell growth, invasion, and migration, there has been a growing amount of interest in the therapeutic potential of targeting Eps. In the present study, we investigated the role of EP4 on the effectiveness of cordycepin in inhibititing the migration and invasion of HCT116 human colorectal carcinoma cells. Our data indicate that cordycepin suppressed lipopolysaccharide (LPS)-enhanced cell migration and invasion through the inactivation of matrix metalloproteinases (MMP)-9 as well as the down-regulation of COX-2 expression and PGE2 production. These events were shown to be associated with the inactivation of EP4 and activation of AMP-activated protein kinase (AMPK). Moreover, the AMPK inhibitor, compound C, as well as AMPK knockdown via siRNA, attenuated the cordycepin-induced inhibition of EP4 expression. Cordycepin treatment also reduced the activation of CREB. These findings indicate that cordycepin suppresses the migration and invasion of HCT116 cells. Through modulating EP4 expression and the AMPK-CREB signaling pathway. Therefore, cordycepin has the potential to serve as a potent anti-cancer agent in therapeutic strategies against colorectal cancer metastasis.

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