Search Results (7)

Gintonin, a non-saponin glycolipoprotein from Panax ginseng, acts as a lysophosphatidic acid ligand. However, its anticancer effects, especially in melanoma, remain unclear. This study investigated the anti-proliferative effects and intracellular signaling mechanisms of a gintonin-enriched fraction (GEF) from Panax ginseng in human melanoma cell lines. In vitro, GEF treatment significantly inhibited cell proliferation, reduced clonogenic potential, and delayed wound healing in melanoma cells. Flow cytometry and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining showed that GEF induced apoptosis, as evidenced by increased apoptotic cell populations and nuclear changes. GEF also caused cell cycle arrest in the G₁ phase for A375 cells and the G₂/M phase for A2058 cells. It triggered apoptotic signaling via activation of caspase-3, -9, poly (ADP-ribose) polymerase cleavage, and downregulation of B cell lymphoma-2 (Bcl-2). GEF treatment also raised intracellular reactive oxygen species (ROS) levels and mitochondrial stress, which were mitigated by N-acetyl cysteine (NAC), an ROS inhibitor. In vivo, GEF suppressed tumor growth in A375- and A2058-xenografted mice without toxicity. These findings suggest that GEF from Panax ginseng has potential antitumor effects in melanoma by inducing apoptosis and cell cycle arrest, presenting a promising therapeutic avenue. Full article

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising chemotherapeutic agent because of its selective apoptotic action on cancer cells. However, resistance to TRAIL-induced apoptosis remains a challenge in many cancers. The gintonin-enriched Panax ginseng extract fraction (GEF) has diverse pharmacological benefits. We explored the combined efficacy of GEF and TRAIL in inducing apoptosis in human renal cell carcinoma (RCC) cells. The effect of GEF treatment on the viability, clonogenic potential, wound healing, and TRAIL-induced apoptotic signaling of RCC cells was studied in vitro. Our investigation revealed that GEF pre-treatment sensitized RCC cells to TRAIL-induced apoptosis, as evidenced by DNA fragmentation and cell proliferation, colony formation, and migration inhibition. This sensitization was linked to the upregulation of death receptors 4 and 5 and alterations in apoptotic protein expression, notably, the decreased expression of the Mu-2-related death-inducing gene, a novel anti-apoptotic protein. Our findings underscore the necessity of caspase activation for GEF/TRAIL-induced apoptosis using the pan-caspase inhibitor Z-VAD-FMK. This study demonstrates that GEF sensitizes human RCC cells to TRAIL-induced apoptosis by upregulating DR4/5 and modulating apoptotic protein expression. These findings suggest a promising strategy for overcoming TRAIL resistance in cancer therapy and highlight the potential of GEF as a valuable adjunct to TRAIL-based treatments. Full article

Ginseng-derived gintonin reportedly contains functional lysophosphatidic acids (LPAs) as LPA receptor ligands. The effect of the gintonin-enriched fraction (GEF) on in vitro and in vivo glucagon-like protein-1 (GLP-1) secretion, which is known to stimulate insulin secretion, via LPA receptor(s) remains unclear. Accordingly, we examined the effects of GEF on GLP-1 secretion using human enteroendocrine NCI-H716 cells. The expression of several of LPA receptor subtypes in NCI-H716 cells using qPCR and Western blotting was examined. LPA receptor subtype expression was in the following order: LPA6 > LPA2 > LPA4 > LPA5 > LPA1 (qPCR), and LPA6 > LPA4 > LPA2 > LPA1 > LPA3 > LPA5 (Western blotting). GEF-stimulated GLP-1 secretion occurred in a dose- and time-dependent manner, which was suppressed by cAMP-Rp, a cAMP antagonist, but not by U73122, a phospholipase C inhibitor. Furthermore, silencing the human LPA6 receptor attenuated GEF-mediated GLP-1 secretion. In mice, low-dose GEF (50 mg/kg, peroral) increased serum GLP-1 levels; this effect was not blocked by Ki16425 co-treatment. Our findings indicate that GEF-induced GLP-1 secretion could be achieved via LPA6 receptor activation through the cAMP pathway. Hence, GEF-induced GLP secretion via LPA6 receptor regulation might be responsible for its beneficial effects on human endocrine physiology. Full article

Obesity is a major health concern and is becoming an increasingly serious societal problem worldwide. The browning of white adipocytes has received considerable attention because of its potential protective effect against obesity-related metabolic disease. The gintonin-enriched fraction (GEF) is a non-saponin, glycolipoprotein component of ginseng that is known to have neuroprotective and anti-inflammatory effects. However, the anti-obesity and browning effects of GEF have not been explored to date. Therefore, we aimed to determine whether GEF has a preventive effect against obesity. We differentiated 3T3-L1 cells and mouse primary subcutaneous adipocytes for 8 days in the presence or absence of GEF, and then measured the expression of intermediates in signaling pathways that regulate triglyceride (TG) synthesis and browning by Western blotting and immunofluorescence analysis. We found that GEF reduced lipid accumulation by reducing the expression of pro-adipogenic and lipogenic factors, and increased lipolysis and thermogenesis, which may be mediated by an increase in the phosphorylation of protein kinase A. These findings suggest that GEF may induce fat metabolism and energy expenditure in white adipocytes and therefore may represent a potential treatment for obesity. Full article

Heat stress can be caused by various environmental factors. When exposed to heat stress, oxidative stress and inflammatory reaction occur due to an increase of reactive oxygen species (ROS) in the body. In particular, inflammatory responses induced by heat stress are common in muscle cells, which are the most exposed to heat stress and directly affected. Gintonin-Enriched Fraction (GEF) is a non-saponin component of ginseng, a glycolipoprotein. It is known that it has excellent neuroprotective effects, therefore, we aimed to confirm the protective effect against heat stress by using GEF. C2C12 cells were exposed to high temperature stress for 1, 12 and 15 h, and the expression of signals was analyzed over time. Changes in the expression of the factors that were observed under heat stress were confirmed at the protein level. Exposure to heat stress increases phosphorylation of p38 and extracellular signal-regulated kinase (ERK) and increases expression of inflammatory factors such as NLRP3 inflammasome through lysophosphatidic acid (LPA) receptor. Activated inflammatory signals also increase the secretion of inflammatory cytokines such as interleukin 6 (IL-6) and interleukin 18 (IL-18). Also, expression of glutathione reductase (GR) and catalase related to oxidative stress is increased. However, it was confirmed that the changes due to the heat stress were suppressed by the GEF treatment. Therefore, we suggest that GEF helps to protect heat stress in muscle cell and prevent tissue damage by oxidative stress and inflammation. Full article

Gintonin is a newly discovered ingredient of ginseng and plays an exogenous ligand for G protein-coupled lysophosphatidic acid receptors. We previously showed that gintonin exhibits diverse effects from neurotransmitter release to improvement of Alzheimer’s disease-related cognitive dysfunctions. However, previous studies did not show whether gintonin has protective effects against environmental heavy metal. We investigated the effects of gintonin-enriched fraction (GEF) on methylmercury (MeHg)-induced neurotoxicity and learning and memory dysfunction and on organ MeHg elimination. Using hippocampal neural progenitor cells (hNPCs) and mice we examined the effects of GEF on MeHg-induced hippocampal NPC neurotoxicity, on formation of reactive oxygen species (ROS), and on in vivo learning and memory functions after acute MeHg exposure. Treatment of GEF to hNPCs attenuated MeHg-induced neurotoxicity with concentration- and time-dependent manner. GEF treatment inhibited MeHg- and ROS inducer-induced ROS formations. Long-term treatment of GEF also improved MeHg-induced learning and memory dysfunctions. Oral administration of GEF decreased the concentrations of MeHg in blood, brain, liver, and kidney. This is the first report that GEF attenuated MeHg-induced in vitro and in vivo neurotoxicities through LPA (lysophosphatidic acids) receptor-independent manner and increased organ MeHg elimination. GEF-mediated neuroprotection might achieve via inhibition of ROS formation and facilitation of MeHg elimination from body. Full article

Gintonin is a newly discovered component of ginseng and acts as a ligand for G protein-coupled lysophosphatidic acid (LPA) receptors. It is currently unclear whether gintonin has skin-related effects. Here, we examined the effects of a gintonin-enriched fraction (GEF) on [Ca²⁺]_i transient induction in human dermal fibroblasts (HDFs). We found that GEF treatment transiently induced [Ca²⁺]_i in a dose-dependent manner. GEF also increased cell viability and proliferation, which could be blocked by Ki16425, an LPA1/3 receptor antagonist, or 1,2-Bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid tetrakis(acetoxymethyl ester) (BAPTA-AM), a calcium chelator. We further found that GEF stimulated hyaluronic acid (HA) release from HDFs in a dose- and time-dependent manner, which could be attenuated by Ki16425, U73122, a phospholipase C inhibitor, 2-Aminoethoxydiphenyl borate (2-APB), an IP₃ receptor antagonist, and BAPTA-AM. Moreover, we found that GEF increased HA synthase 1 (HAS1) expression in a time-dependent manner. We also found that GEF stimulates collagen release and the expression of collagen 1, 3, and 7 synthases in a time-dependent manner. GEF-mediated collagen synthesis could be blocked by Ki16425, U73122, 2-APB, and BAPTA-AM. GEF treatment also increased the mRNA levels of LPA1-6 receptor subtypes at 8 h and increased the protein levels of LPA1-6 receptor subtypes at 8 h. Overall, these results indicate that the GEF-mediated transient induction of [Ca²⁺]_i is coupled to HA and collagen release from HDFs via LPA receptor regulations. We can, thus, conclude that GEF might exert a beneficial effect on human skin physiology via LPA receptors. Full article