Jongkyu Kim

Dr. Jongkyu Kim

orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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30 March 2023 in Metabolites
Verified
Journal Article
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IBImran Bashir
Imran Bashir
JKJoo Wan Kim
Joo Wan Kim
JKJongkyu Kim
Jongkyu Kim
YCYoon-Seok Chun
Yoon-Seok Chun
Jae-Suk ChoiJae-Suk Choi
Jae-Suk Choi
SKSae Kwang Ku
Sae Kwang Ku
To deal with the adverse effects associated with the use of currently available treatments for metabolic disorders, such as type 2 diabetes, there is a need to find an alternative drug compound. In the present study, we investigated the therapeutic potential of black cumin (Nigella sativa L.) seeds extract (BCS extract) for type 2 diabetes using a 45% Kcal-fed obese mouse model. The BCS extract at different doses (400–100 mg/kg) showed a dose-dependent improvement tendency in high-fat diet (HFD)-induced obesity, non-alcoholic fatty liver disease (NAFLD), hyperlipidemia, and diabetic nephropathy compared to the metformin (250 mg/kg). In particular, BCS extract at a dose of 200 mg/kg significantly inhibited the HFD-induced metabolic conditions. The oral administration of BCS extract (200 mg/kg) significantly inhibited the oxidative stress through lipid peroxidation, normalized the activity of sugar metabolism-related enzymes and the expression of genes involved in fat metabolism, and inhibited insulin resistance through glucose and fat metabolism by regulating the 5’-AMP-activated protein kinase (AMPK) expression. Furthermore, BCS extract (200 mg/kg) showed renal damage improvement effects compared to the metformin (250 mg/kg). The results clearly show that BCS aqueous extract at an appropriate concentration could help in the treatment of metabolic disorders, and BCS aqueous extract can be used as a functional food for various diabetic complications, such as obesity, diabetes, and NAFLD.

30 August 2023 in Marine Drugs
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Journal Article
Open access
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JKJongkyu Kim
Jongkyu Kim
NLNamju Lee
Namju Lee
YCYoon-Seok Chun
Yoon-Seok Chun
SLSang-Hoon Lee
Sang-Hoon Lee
SKSae Kwang Ku
Sae Kwang Ku
Krill oil (KO) shows promise as a natural marine-derived ingredient for improving skin health. This study investigated its antioxidant, anti-inflammatory, anti-wrinkle, and moisturizing effects on skin cells and UVB-induced skin photoaging in hairless mice. In vitro assays on HDF, HaCaT, and B16/F10 cells, as well as in vivo experiments on 60 hairless mice were conducted. A cell viability assay, diphenyl-1-picryhydrazyl (DPPH) radical scavenging activity test, elastase inhibition assay, procollagen content test, MMP-1 inhibition test, and hyaluronan production assay were used to experiment on in vitro cell models. Mice received oral KO administration (100, 200, or 400 mg/kg) once a day for 15 weeks and UVB radiation three times a week. L-Ascorbic acid (L-AA) was orally administered at 100 mg/kg once daily for 15 weeks, starting from the initial ultraviolet B (UVB) exposures. L-AA administration followed each UVB session (0.18 J/cm2) after one hour. In vitro, KO significantly countered UVB-induced oxidative stress, reduced wrinkles, and prevented skin water loss by enhancing collagen and hyaluronic synthesis. In vivo, all KO dosages showed dose-dependent inhibition of oxidative stress-induced inflammatory photoaging-related skin changes. Skin mRNA expressions for hyaluronan synthesis and collagen synthesis genes also increased dose-dependently after KO treatment. Histopathological analysis confirmed that krill oil (KO) ameliorated the damage caused by UVB-irradiated skin tissues. The results imply that KO could potentially act as a positive measure in diminishing UVB-triggered skin photoaging and address various skin issues like wrinkles and moisturization when taken as a dietary supplement.

Verified
Journal Article
Open access
PDF file
JKJin-Woo Kim
Jin-Woo Kim
DLDong-Ho Lee
Dong-Ho Lee
KLKang-Woo Lee
Kang-Woo Lee
NNNa Na
Na Na
NLNa-Yeon Lee
Na-Yeon Lee
SSSoon-Mi Shim
Soon-Mi Shim
The current study aimed to investigate the physicochemical properties of the natural eggshell membrane (NEM) and its protective effects against H2O2-induced oxidative stress in human chondrocytes (SW-1353). Bioactive components from NEM related to cartilage were profiled, consisting of 1.1 ± 0.07% hyaluronic acid, 1.2 ± 0.25% total sulfated glycosaminoglycans as chondroitin sulfate, 3.1 ± 0.33% collagen, and 54.4 ± 2.40% total protein. Protein was hydrolyzed up to 43.72 ± 0.76% using in vitro gastro–intestinal digestive enzymes. Peptides eluted at 9.58, 12.46, and 14.58 min using nano-LC-ESI-MS were identified as TEW, SWVE, and VYL peptides with an M/Z value of 435.1874, 520.2402, and 394.2336, respectively. Radical scavenging activity of NEM at 10 mg/mL using the ABTS assay was revealed to be 2.1 times higher than that of the positive control. NEM treatment significantly enhanced cellular SOD expression (p < 0.05). Pre-treatment with NEM (0.1, 1, and 10 mg/mL) dose-dependently reduced H2O2-induced ROS levels in SW-1353. Cell live imaging confirmed that NEM pre-treatment led to a significant reduction in apoptosis expression compared to control. Results from the present study suggest that NEM rich in cartilage protective components including hyaluronic acid, collagen, and chondroitin antioxidative peptides could be a potential therapeutic agent for osteoarthritis (OA) by scavenging oxidative stress.

17 November 2023 in Medicina
Verified
Journal Article
Open access
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IBImran Bashir
Imran Bashir
JKJongkyu Kim
Jongkyu Kim
YCYoon-Seok Chun
Yoon-Seok Chun
Jae-Suk ChoiJae-Suk Choi
Jae-Suk Choi
SKSae Kwang Ku
Sae Kwang Ku
Background and Objectives: This study evaluated the in vitro anti-adipogenic and anti-inflammatory properties of black cumin (Nigella sativa L.) seed extract (BCS extract) as a potential candidate for developing herbal formulations targeting metabolic disorders. Materials and Methods: We evaluated the BCS extract by assessing its 2,2-diphenyl-1-picrohydrazyl (DPPH) radical scavenging activity, levels of prostaglandin E2 (PGE2) and nitric oxide (NO), and mRNA expression levels of key pro-inflammatory mediators. We also quantified the phosphorylation of nuclear factor kappa light chain enhancer of activated B cells (NF-κB) and mitogen-activated protein kinases (MAPK) signaling molecules. To assess anti-adipogenic effects, we used differentiated 3T3-L1 cells and BCS extract in doses from 10 to 100 μg/mL. We also determined mRNA levels of key adipogenic genes, including peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding protein α (C/BEPα), adipocyte protein 2 (aP2), lipoprotein lipase (LPL), fatty acid synthase (FAS), and sterol-regulated element-binding protein 1c (SREBP-1c) using real-time quantitative polymerase chain reaction (qPCR). Results: This study showed a concentration-dependent DPPH radical scavenging activity and no toxicity at concentrations up to 30 μg/mL in Raw264.7 cells. BCS extract showed an IC50 of 328.77 ± 20.52 μg/mL. Notably, pre-treatment with BCS extract (30 μg/mL) significantly enhanced cell viability in lipopolysaccharide (LPS)-treated Raw264.7 cells. BCS extract treatment effectively inhibited LPS-induced production of PGE2 and NO, as well as the expression of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2), inducible NO synthase (iNOS), interleukin (IL)-1β and IL-6, possibly by limiting the phosphorylation of p38, p65, inhibitory κBα (I-κBα), and c-Jun N-terminal kinase (JNK). It also significantly attenuated lipid accumulation and key adipogenic genes in 3T3-L1 cells. Conclusions: This study highlights the in vitro anti-adipogenic and anti-inflammatory potential of BCS extract, underscoring its potential as a promising candidate for managing metabolic disorders.

14 June 2024 in Applied Sciences
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Journal Article
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JKJun-Il Kim
Jun-Il Kim
JCJoo-Hee Choi
Joo-Hee Choi
Min-Soo SeoMin-Soo Seo
Min-Soo Seo
JKJongkyu Kim
Jongkyu Kim
YCYoon-Seok Chun
Yoon-Seok Chun
SKSae Kwang Ku
Sae Kwang Ku
Osteoarthritis (OA) is a degenerative joint disease that mainly occurs due to the cellular inflammatory response and the destruction of joint cartilage. Natural eggshell membrane (NEM), a byproduct of egg processing, might be a promising knee OA treatment because of its anti-inflammatory properties and resemblance to synovial membrane components. Therefore, we aimed to study the anti-inflammatory effects of NEM in OA, utilizing both in vitro experiments with primary chondrocytes and in vivo studies with a surgical rat model of knee OA. In vitro studies showed that NEM treatment improved cell viability in chondrocytes exposed to interleukin-1α by upregulating chondrogenic genes and inhibiting enzymes that degrade the extracellular matrix (ECM). Furthermore, the anti-inflammatory effects of NEM were observed in chondrocytes induced by lipopolysaccharide. Administering NEM orally for 56 days after OA surgery resulted in enhanced joint swelling reduction and improved mobility in animal models, as well as an increase in bone density and cartilage compressive strength in a concentration-dependent manner. It inhibited inflammatory markers (5-lipoxygenase and prostaglandin E2) and extracellular matrix (ECM)-degrading enzymes (MMP-2 and MMP-9) in both the cartilage and synovium. Simultaneously, there was an upregulation in the expression of chondrogenic genes (Sox9, aggrecan, and Col-2). The histopathological and immunohistochemical analyses demonstrated that NEM’s anti-inflammatory, anti-apoptotic, and chondrogenic properties contributed to the mitigation of joint degradation and synovial inflammation. Therefore, NEM is a potential alternative or functional food agent that addresses both anti-inflammatory and chondroprotective aspects in OA.

31 January 2025 in Antioxidants
Verified
Journal Article
Open access
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JKJongkyu Kim
Jongkyu Kim
YCYoon-Seok Chun
Yoon-Seok Chun
NYNam-kyu Yoon
Nam-kyu Yoon
BKByung-Kwon Kim
Byung-Kwon Kim
KCKiin Choi
Kiin Choi
NLNamju Lee
Namju Lee
Thymoquinone (TQ), a bioactive compound derived from black cumin seeds, is renowned for its potent anti-obesity and anti-diabetic properties. Due to the stability challenges of TQ, it has predominantly been utilized in oil formulations. This study aimed to enhance the stability of TQ and investigated the impact of consuming insoluble fiber from black cumin seeds on restoring antioxidant function compromised by diabetes and improving hyperglycemia management. We evaluated the restorative effects of a 35-day administration of black cumin seed extract (BCS) on antioxidant function impaired by streptozotocin (STZ)-induced diabetes, alongside structural and functional alterations in the pancreas, liver, and kidneys. The results demonstrated significant improvements in organ weight, particularly in pancreatic tissue. Moreover, BCS administration markedly suppressed the expression of key genes associated with pancreatic dysfunction and damage, including caspase-3, transforming growth factor-beta 1 (TGF-β1), and interleukin-1 beta (IL-1β). Through oral glucose tolerance tests (OGTTs), BCS was found to effectively regulate chronic hyperglycemia and exhibit potential for managing acute hyperglycemia. These findings suggest that BCS not only addresses both glycemic and non-glycemic complications of diabetes but also offers a safe, long-term solution. Consequently, BCS emerges as a promising therapeutic agent for hyperglycemia management, including in prediabetic stages.