• Journal of Ginseng Research
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• 제37권4호
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• pp.401-412
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• 2013

Korean Red Ginseng (KRG) is an oriental herbal preparation obtained from Panax ginseng Meyer (Araliaceae). To expand our understanding of the action of KRG on central nervous system (CNS) function, we examined the effects of KRG on tissue plasminogen activator (tPA)/plasminogen activator inhibitor-1 (PAI-1) expression in rat primary astrocytes. KRG extract was treated in cultured rat primary astrocytes and neuron in a concentration range of 0.1 to 1.0 mg/mL and the expression of functional tPA/PAI-1 was examined by casein zymography, Western blot and reverse transcription-polymerase chain reaction. KRG extracts increased PAI-1 expression in rat primary astrocytes in a concentration dependent manner (0.1 to 1.0 mg/mL) without affecting the expression of tPA itself. Treatment of 1.0 mg/mL KRG increased PAI-1 protein expression in rat primary astrocytes to $319.3{\pm}65.9%$ as compared with control. The increased PAI-1 expression mediated the overall decrease in tPA activity in rat primary astrocytes. Due to the lack of PAI-1 expression in neuron, KRG did not affect tPA activity in neuron. KRG treatment induced a concentration dependent activation of PI3K, p38, ERK1/2, and JNK in rat primary astrocytes and treatment of PI3K or MAPK inhibitors such as LY294002, U0126, SB203580, and SP600125 (10 ${\mu}M$ each), significantly inhibited 1.0 mg/mL KRG-induced expression of PAI-1 and down-regulation of tPA activity in rat primary astrocytes. Furthermore, compound K but not other ginsenosides such as Rb1 and Rg1 induced PAI-1 expression. KRG-induced up-regulation of PAI-1 in astrocytes may play important role in the regulation of overall tPA activity in brain, which might underlie some of the beneficial effects of KRG on CNS such as neuroprotection in ischemia and brain damaging condition as well as prevention or recovery from addiction.

• Biomolecules & Therapeutics
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• 제31권1호
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• pp.73-81
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• 2023

Sirtuins (SIRTs) belong to the nicotinamide adenine dinucleotide (NAD+)-dependent class III histone deacetylase family. They are key regulators of cellular and physiological processes, such as cell survival, senescence, differentiation, DNA damage and stress response, cellular metabolism, and aging. SIRTs also influence carcinogenesis, making them potential targets for anticancer therapeutic strategies. In this study, we investigated the anticancer properties and underlying molecular mechanisms of a novel SIRT1 inhibitor, MHY2251, in human colorectal cancer (CRC) cells. MHY2251 reduced the viability of various human CRC cell lines, especially those with wild-type TP53. MHY2251 inhibited SIRT1 activity and SIRT1/2 protein expression, while promoting p53 acetylation, which is a target of SIRT1 in HCT116 cells. MHY2251 treatment triggered apoptosis in HCT116 cells. It increased the percentage of late apoptotic cells and the sub-G1 fraction (as detected by flow cytometric analysis) and induced DNA fragmentation. In addition, MHY2251 upregulated the expression of FasL and Fas, altered the ratio of Bax/Bcl-2, downregulated the levels of pro-caspase-8, -9, and -3 proteins, and induced subsequent poly(ADP-ribose) polymerase cleavage. The induction of apoptosis by MHY2251 was related to the activation of the caspase cascade, which was significantly attenuated by pre-treatment with Z-VAD-FMK, a pan-caspase inhibitor. Furthermore, MHY2251 stimulated the phosphorylation of c-Jun N-terminal kinase (JNK), and MHY2251-triggered apoptosis was blocked by pre-treatment with SP600125, a JNK inhibitor. This finding indicated the specific involvement of JNK in MHY2251-induced apoptosis. MHY2251 shows considerable potential as a therapeutic agent for targeting human CRC via the inhibition of SIRT1 and activation of JNK/p53 pathway.

• 생명과학회지
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• 제33권2호
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• pp.176-182
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• 2023

석곡의 줄기는 전통 동양의학에서 위를 보하고, 진액을 보충하며, 열을 내리는 것에 사용되어 왔다. 본 연구에서는 RBL-2H3 세포에서 비만세포 탈과립과 TNF-α, IL-4, histidine decarboxylase (HDC) 발현에 미치는 석곡 열수추출물(DME)의 효과를 조사하였다. DME는 PMA와 Calcium ionophore 병행처리(PMACI)에 의해 유도되는 β-hexosaminidase 분비와 TNF-α, IL-4, HDC 발현을 현저히 억제하였다. 또한 PMACI에 의해 유도되는 NF-κB, AP-1 활성과 p38 kinase, extracellular signal-regulated kinase 1/2 (ERK1/2)과 c-Jun N-terminal kinase (JNK)의 인산화가 DME 전처리에 의해 저해되었다. 이러한 결과들은DME가 비만세포 탈과립을 억제하고, MAPKs/NF-κB/AP-1 신호전달 경로를 통해 TNF-α, IL-4, HDC 발현을 억제한다는 것을 시사한다. 본 연구결과들로 보아 DME는 과민반응과 염증성 질환을 치료하는 약물로 개발될 가능성을 가지는 것으로 사료된다.

• 생명과학회지
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• 제17권10호
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• pp.1447-1451
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• 2007

해양생물 유래 항암활성을 가지는 천연물의 탐색과정에서 해면동물에서 유래된 PTX-2는 p53 결손 암세포에서 세포독성 효과가 높은 것으로 보고된 바 있다. 본 연구에서는 인체 간암세포 모델을 이용하여 PTX-2의 효능을 조사한 결과는 p53 결손 Hep3B 세포에서 p53 정상 HepG2에 비하여 항암활성이 매우 높았으며, 이는 apoptosis 유발과 연관성이 있음을 확인하였다. PTX-2에 의한 Hep3B 세포의 apoptosis 유발은 DFF family의 발현 변화, pro-apoptotic Bax 및 Bcl-xS 단백질의 발현 증가, caspases (-3, -8 및 -9)의 활성화 등이 관여함을 알 수 있었다. PTX-2는 또한 Hep3B 세포에서 AKT 및 ERK1/2의 활성화를 유도하였으며, caspase-3, AKT 및 ERK1/2의 특이적 저해제에 의하여 PTX-2에 의한 세포증식 억제 효능이 유의적으로 감소되었다. 본 연구는 PTX-2에 의한 Hep3B 세포에서의 apoptosis 유도에 AKT 및 ERK1/2 신호 전달 경로가 중요한 역할을 하고 있음을 보여주는 결과이다.