A brief method for preparation of gintonin-enriched fraction from ginseng

Gintonin-Enriched Panax ginseng Extract Fraction Sensitizes Renal Carcinoma Cells to TRAIL-Induced Apoptosis through DR4/5 Upregulation

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.

Gintonin Alleviates HCl/Ethanol- and Indomethacin-Induced Gastric Ulcers in Mice

Gintonin, newly extracted from ginseng, is a glycoprotein that acts as an exogenous lysophosphatidic acid (LPA) receptor ligand. This study aimed to demonstrate the in vivo preventive effects of gintonin on gastric damage. ICR mice were randomly assigned to five groups: a normal group (received saline, 0.1 mL/10 g, p.o.); a control group (administered 0.3 M HCl/ethanol, 0.1 mL/10 g, p.o.) or indomethacin (30 mg/kg, p.o.); gintonin at two different doses (50 mg/kg or 100 mg/kg, p.o.) with either 0.3 M HCl/ethanol or indomethacin; and a positive control (Ranitidine, 40 mg/kg, p.o.). After gastric ulcer induction, the gastric tissue was examined to calculate the ulcer index. The expression of gastric damage markers, such as tumor necrosis factor (TNF)-α, cyclooxygenase 2 (COX-2), and LPA2 and LPA5 receptors, were measured by Western blotting. Interleukin-6 (IL-6) and prostaglandin E2 (PGE2) levels were measured by enzyme-linked immunosorbent assay. The platelet endothelial cell adhesion molecule (PECAM-1), Evans blue, and occludin levels in gastric tissues were measured using immunofluorescence analysis. Both HCl/ethanol- and indomethacin-induced gastric ulcers showed increased TNF-α, IL-6, Evans blue permeation, and PECAM-1, and decreased COX-2, PGE2, occludin, and LPA5 receptor expression levels. However, oral administration of gintonin alleviated the gastric ulcer index induced by HCl/ethanol and indomethacin in a dose-dependent manner. Gintonin suppressed TNF-α and IL-6 expression, but increased COX-2 expression and PGE2 levels in mouse gastric tissues. Gintonin intake also increased LPA5 receptor expression in mouse gastric tissues. These results indicate that gintonin can play a role in gastric protection against gastric damage induced by HCl/ethanol or indomethacin.

Gintonin stimulates dendritic growth in striatal neurons by activating Akt and CREB

Gintonin, a glycolipid protein conjugated with lysophosphatidic acid (LPA), is a newly identified compound extracted from Korean ginseng. LPA receptor isotypes exhibit high affinity for gintonin and mediate intracellular calcium signaling in various animal cell models. In this study, we found that gintonin induced the activation of Akt and cAMP-response element binding protein (CREB) in mouse striatal neurons, and chronic treatment with gintonin potently induced dendritic growth and filopodia formation. Gintonin-induced Akt/CREB activation and dendritic development were significantly impaired by LPA receptor (LPAR1/3) inhibition with Ki16425. Intriguingly, prolonged treatment with gintonin ameliorated the reduction in dendritic formation caused by Shank3 and Slitrk5 deficiency in the striatal neurons. In addition, gintonin and brain-derived neurotrophic factor (BDNF) had a synergistic effect on AKT/CREB activation and dendritic growth at suboptimal concentrations. These findings imply that gintonin-stimulated LPA receptors play a role in dendritic growth in striatal neurons and that they may act synergistically with BDNF, which is known to play a role in dendritogenesis.

Visualization of the binding between gintonin, a Panax ginseng-derived LPA receptor ligand, and the LPA receptor subtypes and transactivation of the EGF receptor

Background

Gintonin is a ginseng-derived exogenous G-protein-coupled lysophosphatidic acid (LPA) receptor ligand. Gintonin exerts its neuronal and non-neuronal in vitro and in vivo effects through LPA receptor subtypes. However, it is unknown whether gintonin can bind to the plasma membrane of cells and can transactivate the epidermal growth factor (EGF) receptor. In the present study, we examined whether gintonin-biotin conjugates directly bound to LPA receptors and transactivated the EGF receptor.

Methods

We designed gintonin-biotin conjugates through gintonin biotinylation and examined whether gintonin-biotin conjugate binding sites co-localized with the LPA receptor subtype binding sites. We further examined whether gintonin-biotin transactivated the EGF receptor via LPA receptor regulation via phosphor-EGF and cell migration assays.

Results

Gintonin-biotin conjugates elicit [Ca2+]i transient similar to that observed with unbiotinylated gintonin in cultured PC3 cells, suggesting that biotinylation does not affect physiological activity of gintonin. We proved that gintonin-biotin conjugate binding sites co-localized with the LPA1/6 receptor binding sites. Gintonin-biotin binding to the LPA1 receptor transactivates the epidermal growth factor (EGF) receptor through phosphorylation, while the LPA1/3 receptor antagonist, Ki16425, blocked phosphorylation of the EGF receptor. Additionally, an EGF receptor inhibitor AG1478 blocked gintonin-biotin conjugate-mediated cell migration.

Conclusions

We observed the binding between ginseng-derived gintonin and the plasma membrane target proteins corresponding to the LPA1/6 receptor subtypes. Moreover, gintonin transactivated EGF receptors via LPA receptor regulation. Our results suggest that gintonin directly binds to the LPA receptor subtypes and transactivates the EGF receptor. It may explain the molecular basis of ginseng physiology/pharmacology in biological systems.

Effects of Gintonin-enriched fraction on the gene expression of six lysophosphatidic receptor subtypes

Background

Gintonin, isolated from ginseng, acts as a ginseng-derived lysophosphatidic acid (LPA) receptor ligand and elicits the [Ca²⁺]_i transient through six LPA receptor subtypes (LPARSs). However, the long-term effects of gintonin-enriched fraction (GEF) on the gene expression of six LPARSs remain unknown. We examined changes in the gene expression of six LPA receptors in the mouse whole brain, heart, lungs, liver, kidneys, spleen, small intestine, colon, and testis after long-term oral GEF administration.

Methods

C57BL/6 mice were divided into two groups: control vehicle and GEF (100 mg/kg, p.o.). After 21-day saline or GEF treatment, total RNA was extracted from nine mouse organs. Quantitative-real-time PCR (qRT-PCR) and western blot were performed to quantify changes in the gene and protein expression of the six LPARSs, respectively.

Results

qRT-PCR analysis before GEF treatment revealed that the LPA6 RS was predominant in all organs except the small intestine. The LPA2 RS was most abundant in the small intestine. Long-term GEF administration differentially regulated the six LPARSs. Upon GEF treatment, the LPA6 RS significantly increased in the liver, small intestine, colon, and testis but decreased in the whole brain, heart, lungs, and kidneys. Western blot analysis of the LPA6 RS confirmed the differential effects of GEF on LPA6 receptor protein levels in the whole brain, liver, small intestine, and testis.

Conclusion

The LPA6 receptor was predominantly expressed in all nine organs examined; long-term oral GEF administration differentially regulated LPA3, LPA4, and LPA6 receptors in the whole brain, heart, lungs, liver, kidneys, small intestine, and testis.

Amelioration of muscle wasting by gintonin in cancer cachexia

Cancer cachexia is characterized by systemic inflammation, protein degradation, and loss of skeletal muscle. Despite extensive efforts to develop therapeutics, only few effective treatments are available to protect against cancer cachexia. Here, we found that gintonin (GT), a ginseng-derived lysophosphatidic acid receptor (LPAR) ligand, protected C2C12 myotubes from tumor necrosis factor α (TNFα)/interferon γ (IFNγ)- induced muscle wasting condition. The activity of GT was found to be dependent on LPAR/Gαi2, as the LPAR antagonist Ki16425 and Gαi2 siRNA abolished the anti-atrophic effects of GT on myotubes. GT suppressed TNFα-induced oxidative stress by reducing reactive oxygen species and suppressing inflammation-related genes, such as interleukin 6 (IL-6) and NADPH oxidase 2 (NOX-2). In addition, GT exhibited anti-atrophy effects in primary normal human skeletal myoblasts. Further, GT protected against Lewis lung carcinoma cell line (LLC1)-induced cancer cachexia in a mouse model. Specifically, GT rescued the lower levels of grip strength, hanging, and cross-sectional area caused by LLC1. Collectively, our findings suggest that GT may be a good therapeutic candidate for protecting against cancer cachexia.

Gintonin-enriched fraction improves sarcopenia by maintaining immune homeostasis in 20- to 24-month-old C57BL/6J mice

Background

Gintonin-enriched fraction (GEF) is a new non-saponin component glycolipoprotein isolated from ginseng root. This study examined the effect of GEF on age-related sarcopenia in old C57BL/6J mice.

Methods

Young (3–6 months) and old (20–24 months) C57BL/6J mice received oral GEF (50 mg/kg/day or 150 mg/kg/day) daily for 5 weeks. During the oral administration period, body weight and grip strength were measured weekly. After sacrifice, muscles from the hindlimb were excised and used for hematoxylin and eosin staining and western blotting to determine the effects of GEF on sarcopenia. The thymus was photographed to compare size, and flow cytometry was performed to examine the effect of GEF on immune homeostasis in the thymus and spleen. Blood samples were collected, and the concentrations of pro-inflammatory cytokines and IGF-1 were measured.

Results

GEF caused a significant increase in muscle strength, mass, and fiber size in old mice. GEF restored age-related disruption of immune homeostasis by maintaining T cell compartments and regulating inflammatory biomarkers. Thus, GEF reduced common low-grade chronic inflammatory parameters, which are the main cause of muscle loss.

Conclusion

GEF maintained immune homeostasis and inhibited markers of chronic inflammation, resulting in anti-sarcopenia effects in aged C57BL/6J mice. Thus, GEF is a potential therapeutic agent that slows sarcopenia in the elderly.

Gintonin-enriched fraction protects against sarcopenic obesity by promoting energy expenditure and attenuating skeletal muscle atrophy in high-fat diet-fed mice

Background

Gintonin-enriched fraction (GEF), a non-saponin fraction of ginseng, is a novel glycolipoprotein rich in hydrophobic amino acids. GEF has recently been shown to regulate lipid metabolism and browning in adipocytes; however, the mechanisms underlying its effects on energy metabolism and whether it affects sarcopenic obesity are unclear. We aimed to evaluate the effects of GEF on skeletal muscle atrophy in high-fat diet (HFD)-induced obese mice.

Methods

To examine the effect of GEF on sarcopenic obesity, 4-week-old male ICR mice were used. The mice were divided into four groups: chow diet (CD), HFD, HFD supplemented with 50 mg/kg/day GEF, or 150 mg/kg/day GEF for 6 weeks. We analyzed body mass gain and grip strength, histological staining, western blot analysis, and immunofluorescence to quantify changes in sarcopenic obesity-related factors.

Results

GEF inhibited body mass gain while HFD-fed mice gained 22.7 ± 2.0 g, whereas GEF-treated mice gained 14.3 ± 1.2 g for GEF50 and 11.8 ± 1.6 g for GEF150 by downregulating adipogenesis and inducing lipolysis and browning in white adipose tissue (WAT). GEF also enhanced mitochondrial biogenesis threefold in skeletal muscle. Furthermore, GEF-treated skeletal muscle exhibited decreased expression of muscle-specific atrophic genes, and promoted myogenic differentiation and increased muscle mass and strength in a dose-dependent manner (p < 0.05).

Conclusion

These findings indicate that GEF may have potential uses in preventing sarcopenic obesity by promoting energy expenditure and attenuating skeletal muscle atrophy.

Ginseng gintonin, aging societies, and geriatric brain diseases

BACKGROUND

A dramatic increase in aging populations and low birth rates rapidly drive aging societies and increase aging-associated neurodegenerative diseases. However, functional food or medicinal formulations to prevent geriatric brain disorders are not readily available. Panax ginseng is a candidate, since ginseng has long-been consumed as a rejuvenating agent. However, the underlying molecular mechanisms and the components of ginseng that are responsible for brain rejuvenation and human longevity are unknown. Accumulating evidence shows that gintonin is a candidate for the anti-aging ingredient of ginseng, especially in brain senescence.

METHODS

Gintonin, a glycolipoprotein complex, contains three lipid-derived G protein-coupled receptor ligands: lysophosphatidic acids (LPAs), lysophosphatidylinositols (LPIs), and linoleic acid (LA). LPA, LPI, and LA act on six LPA receptor subtypes, GPR55, and GPR40, respectively. These G protein-coupled receptors are distributed within the nervous and non-nervous systems of the human body.

RESULTS

Gintonin-enriched fraction (GEF) exhibits anti-brain senescence and effects against disorders such as Alzheimer's disease (AD), Huntington's disease (HD), and Parkinson's disease (PD). Oral administration of gintonin in animal models of d-galactose-induced brain aging, AD, HD, and PD restored cognitive and motor functions. The underlying molecular mechanisms of gintonin-mediated anti-brain aging and anti-neurodegenerative diseases include neurogenesis, autophagy stimulation, anti-apoptosis, anti-oxidative stress, and anti-inflammatory activities. This review describes the characteristics of gintonin and GEF, and how gintonin exerts its effects on brain aging and brain associated-neurodegenerative diseases.

CONCLUSION

Finally, we describe how GEF can be applied to improve the quality of life of senior citizens in aging societies.

The Gintonin-Enriched Fraction of Ginseng Regulates Lipid Metabolism and Browning via the cAMP-Protein Kinase a Signaling Pathway in Mice White Adipocytes

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.

Effects of gintonin-enriched fraction on hippocampal gene expressions

Background

Recently, gintonin and gintonin-enriched fraction (GEF) have been isolated from ginseng, a herbal medicine. Gintonin induces [Ca²⁺]_i transition in cultured hippocampal neurons and stimulates acetylcholine release through LPA receptor activation. Oral administration of GEF is linked to hippocampus-dependent cognitive enhancement and other neuroprotective effects; however, effects of its long-term administration on hippocampal gene expression remains unknown. Here, we used next-generation sequence (NGS) analysis to examine changes in hippocampal gene expressions after long-term oral administration of GEF.

Methods

C57BL/6 mice were divided into three groups: control group, GEF50 (GEF 50 mg/kg, p.o.), and GEF100 (GEF 100 mg/kg, p.o.). After 22 days, total RNA was extracted from mouse hippocampal tissues. NGS was used for gene expression profiling; quantitative-real-time PCR and western blot were performed to quantify the changes in specific genes and to confirm the protein expression levels in treatment groups.

Results

NGS analysis screened a total of 23,282 genes, analyzing 11-related categories. We focused on the neurogenesis category, which includes four genes for candidate markers: choline acetyltransferase (ChAT) gene, β₃-adrenergic receptor (Adrb3) gene, and corticotrophin-releasing hormone (Crh) gene, and tryptophan 2,3-dioxygenase (Tdo2) gene. Real-time PCR showed a marked overexpression of ChAT, Adrb3, and Crh genes, while reduced expression of Tdo2. Western blot analysis also confirmed increased ChAT and decreased Tdo2 protein levels.

Conclusion

We found that GEF affects mouse hippocampal gene expressions, associated with memory, cognitive, anti-stress and anti-anxiety functions, and neurodegeneration at differential degree, that might explain the genetic bases of GEF-mediated neuroprotective effects.

To Inhibit or Enhance? Is There a Benefit to Positive Allosteric Modulation of P2X Receptors?

The family of ligand-gated ion channels known as P2X receptors were discovered several decades ago. Since the cloning of the seven P2X receptors (P2X1-P2X7), a huge research effort has elucidated their roles in regulating a range of physiological and pathophysiological processes. Transgenic animals have been influential in understanding which P2X receptors could be new therapeutic targets for disease. Furthermore, understanding how inherited mutations can increase susceptibility to disorders and diseases has advanced this knowledge base. There has been an emphasis on the discovery and development of pharmacological tools to help dissect the individual roles of P2X receptors and the pharmaceutical industry has been involved in pushing forward clinical development of several lead compounds. During the discovery phase, a number of positive allosteric modulators have been described for P2X receptors and these have been useful in assigning physiological roles to receptors. This review will consider the major physiological roles of P2X1-P2X7 and discuss whether enhancement of P2X receptor activity would offer any therapeutic benefit. We will review what is known about identified compounds acting as positive allosteric modulators and the recent identification of drug binding pockets for such modulators.

Ginseng gintonin alleviates neurological symptoms in the G93A-SOD1 transgenic mouse model of amyotrophic lateral sclerosis through lysophosphatidic acid 1 receptor

Background

We recently showed that gintonin, an active ginseng ingredient, exhibits antibrain neurodegenerative disease effects including multiple target mechanisms such as antioxidative stress and antiinflammation via the lysophosphatidic acid (LPA) receptors. Amyotrophic lateral sclerosis (ALS) is a spinal disease characterized by neurodegenerative changes in motor neurons with subsequent skeletal muscle paralysis and death. However, pathophysiological mechanisms of ALS are still elusive, and therapeutic drugs have not yet been developed. We investigate the putative alleviating effects of gintonin in ALS.

Methods

The G93A-SOD1 transgenic mouse ALS model was used. Gintonin (50 or 100 mg/kg/day, p.o.) administration started from week seven. We performed histological analyses, immunoblot assays, and behavioral tests.

Results

Gintonin extended mouse survival and relieved motor dysfunctions. Histological analyses of spinal cords revealed that gintonin increased the survival of motor neurons, expression of brain-derived neurotrophic factors, choline acetyltransferase, NeuN, and Nissl bodies compared with the vehicle control. Gintonin attenuated elevated spinal NAD(P) quinone oxidoreductase 1 expression and decreased oxidative stress-related ferritin, ionized calcium-binding adapter molecule 1-immunoreactive microglia, S100β-immunoreactive astrocyte, and Olig2-immunoreactive oligodendrocytes compared with the control vehicle. Interestingly, we found that the spinal LPA1 receptor level was decreased, whereas gintonin treatment restored decreased LPA1 receptor expression levels in the G93A-SOD1 transgenic mouse, thereby attenuating neurological symptoms and histological deficits.

Conclusion

Gintonin-mediated symptomatic improvements of ALS might be associated with the attenuations of neuronal loss and oxidative stress via the spinal LPA1 receptor regulations. The present results suggest that the spinal LPA1 receptor is engaged in ALS, and gintonin may be useful for relieving ALS symptoms.

Ginseng Gintonin Attenuates Lead-Induced Rat Cerebellar Impairments during Gestation and Lactation

Gintonin, a novel ginseng-derived lysophosphatidic acid receptor ligand, improves brain functions and protects neurons from oxidative stress. However, little is known about the effects of gintonin against Pb-induced brain maldevelopment. We investigated the protective effects of gintonin on the developing cerebellum after prenatal and postnatal Pb exposure. Pregnant female rats were randomly divided into three groups: control, Pb (0.3% Pb acetate in drinking water), and Pb plus gintonin (100 mg/kg, p.o.). Blood Pb was increased in dams and pups; gintonin treatment significantly decreased blood Pb. On postnatal day 21, the number of degenerating Purkinje cells was remarkably increased while the number of calbindin-, GAD67-, NMDAR1-, LPAR1-immunoreactive intact Purkinje cells, and GABA transporter 1-immunoreactive pinceau structures were significantly reduced in Pb-exposed offspring. Following Pb exposure, gintonin ameliorated cerebellar degenerative effects, restored increased pro-apoptotic Bax, and decreased anti-apoptotic Bcl2. Gintonin treatment attenuated Pb-induced accumulation of oxidative stress (Nrf2 and Mn-SOD) and inflammation (IL-1β and TNFα,), restoring the decreased cerebellar BDNF and Sirt1. Gintonin ameliorated Pb-induced impairment of myelin basic protein-immunoreactive myelinated fibers of Purkinje cells. Gintonin attenuated Pb-induced locomotor dysfunctions. The present study revealed the ameliorating effects of gintonin against Pb, suggesting the potential use of gintonin as a preventive agent in Pb poisoning during pregnancy and lactation.

Gintonin-Enriched Fraction Suppresses Heat Stress-Induced Inflammation Through LPA Receptor

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.

Effects of Gintonin-Enriched Fraction on Methylmercury-Induced Neurotoxicity and Organ Methylmercury Elimination

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.

Gintonin modulates platelet function and inhibits thrombus formation via impaired glycoprotein VI signaling

Panax ginseng (P. ginseng), one of the most valuable medicinal plants, is known for its healing and immunobooster properties and has been widely used in folk medicine against cardiovascular diseases, including stroke and heart attack. In this study, we explored the anti-platelet activity of gintonin (a recently discovered non-saponin fraction of ginseng) against agonist-induced platelet activation. In vitro effects of gintonin on agonist-induced human and rat platelet aggregation, granule secretion, integrin α_IIbβ₃ activation, and intracellular calcium ion ([Ca²⁺]_i) mobilization were examined. Western blot analysis and immunoprecipitation techniques were used to estimate the expression of mitogen-activated protein kinases (MAPKs) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) and interaction of glycoprotein VI (GPVI) signaling pathway molecules such as Src family kinases (SFK), tyrosine kinase Syk, and PLCγ2. In vivo effects were studied using acute pulmonary thromboembolism model in mice. Gintonin remarkably inhibited collagen-induced platelet aggregation and suppressed granule secretion, [Ca²⁺]_i mobilization, and fibrinogen binding to integrin α_IIbβ₃ in a dose-dependent manner and clot retraction. Gintonin attenuated the activation of MAPK molecules and PI3K/Akt pathway. It also inhibited SFK, Syk, and PLCγ2 activation and protected mice from thrombosis. Gintonin inhibited agonist-induced platelet activation and thrombus formation through impairment in GPVI signaling molecules, including activation of SFK, Syk, PLCγ2, MAPK, and PI3K/Akt; suggesting its therapeutic potential against platelet related CVD.

Multi-Target Protective Effects of Gintonin in 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-Mediated Model of Parkinson's Disease via Lysophosphatidic Acid Receptors

Gintonin is a ginseng-derived lysophosphatidic acid receptor (LPAR) ligand. Although previous in vitro and in vivo studies demonstrated the therapeutic role of gintonin against Alzheimer's disease, the neuroprotective effects of gintonin in Parkinson's disease (PD) are still unknown. We investigated whether gintonin (50 and 100 mg/kg/day, p.o., daily for 12 days) had neuroprotective activities against neurotoxicity in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD. Pre-administration of 100 mg/kg gintonin displayed significantly ameliorating effects in neurological disorders (motor and welfare) as measuring using pole, rotarod, and nest building tests, and in the survival rate. These effects were associated to the reduction of the loss of tyrosine hydroxylase-positive neurons, microglial activation, activation of inflammatory mediators (interleukin-6, tumor necrosis factor, and cyclooxygenase-2), and alteration of blood-brain barrier (BBB) integrity in the substantia nigra pars compacta and/or striatum following MPTP injection. The benefits of gintonin treatment against MPTP also included the activation of the nuclear factor erythroid 2-related factor 2 pathways and the inhibition of phosphorylation of the mitogen-activated protein kinases and nuclear factor-kappa B signaling pathways. Interestingly, these neuroprotective effects of gintonin were blocked by LPAR1/3 antagonist, Ki16425. Overall, the present study shows that gintonin attenuates MPTP-induced neurotoxicity via multiple targets. Gintonin combats neuronal death, and acts as an anti-inflammatory and an anti-oxidant agent. It maintains BBB integrity. LPA receptors play a key role in gintonin-mediated anti-PD mechanisms. Finally, gintonin is a key agent for prevention and/or treatment of PD.

Bioactive lipids in gintonin-enriched fraction from ginseng

Background

Ginseng is a traditional herbal medicine for human health. Ginseng contains a bioactive ligand named gintonin. The active ingredient of gintonin is lysophosphatidic acid C18:2 (LPA C18:2). We previously developed a method for gintonin-enriched fraction (GEF) preparation to mass-produce gintonin from ginseng. However, previous studies did not show the presence of other bioactive lipids besides LPAs. The aim of this study was to quantify the fatty acids, lysophospholipids (LPLs), and phospholipids (PLs) besides LPAs in GEF.

Methods

We prepared GEF from white ginseng. We used gas chromatography-mass spectrometry for fatty acid analysis and liquid chromatography-tandem mass spectrometry for PL analysis, and quantified the fatty acids, LPLs, and PLs in GEF using respective standards. We examined the effect of GEF on insulin secretion in INS-1 cells.

Results

GEF contains about 7.5% linoleic (C18:2), 2.8% palmitic (C16:0), and 1.5% oleic acids (C18:1). GEF contains about 0.2% LPA C18:2, 0.06% LPA C16:0, and 0.02% LPA C18:1. GEF contains 0.08% lysophosphatidylcholine, 0.03% lysophosphatidylethanolamine, and 0.13% lysophosphatidylinositols. GEF also contains about 1% phosphatidic acid (PA) 16:0-18:2, 0.5% PA 18:2-18:2, and 0.2% PA 16:0-18:1. GEF-mediated insulin secretion was not blocked by LPA receptor antagonist.

Conclusion

We determined four characteristics of GEF through lipid analysis and insulin secretion. First, GEF contains a large amount of linoleic acid (C18:2), PA 16:0-18:2, and LPA C18:2 compared with other lipids. Second, the main fatty acid component of LPLs and PLs is linoleic acid (C18:2). Third, GEF stimulates insulin secretion not through LPA receptors. Finally, GEF contains bioactive lipids besides LPAs.

A highly efficient sorbitol dehydrogenase from Gluconobacter oxydans G624 and improvement of its stability through immobilization

A sorbitol dehydrogenase (GoSLDH) from Gluconobacter oxydans G624 (G. oxydans G624) was expressed in Escherichia coli BL21(DE3)-CodonPlus RIL. The complete 1455-bp codon-optimized gene was amplified, expressed, and thoroughly characterized for the first time. GoSLDH exhibited K_m and k_cat values of 38.9 mM and 3820 s⁻¹ toward L-sorbitol, respectively. The enzyme exhibited high preference for NADP⁺ (vs. only 2.5% relative activity with NAD⁺). GoSLDH sequencing, structure analyses, and biochemical studies, suggested that it belongs to the NADP⁺-dependent polyol-specific long-chain sorbitol dehydrogenase family. GoSLDH is the first fully characterized SLDH to date, and it is distinguished from other L-sorbose-producing enzymes by its high activity and substrate specificity. Isothermal titration calorimetry showed that the protein binds more strongly to D-sorbitol than other L-sorbose-producing enzymes, and substrate docking analysis confirmed a higher turnover rate. The high oxidation potential of GoSLDH for D-sorbitol was confirmed by cyclovoltametric analysis. Further, stability of GoSLDH significantly improved (up to 13.6-fold) after cross-linking of immobilized enzyme on silica nanoparticles and retained 62.8% residual activity after 10 cycles of reuse. Therefore, immobilized GoSLDH may be useful for L-sorbose production from D-sorbitol.

Oral Administration of Gintonin Attenuates Cholinergic Impairments by Scopolamine, Amyloid-β Protein, and Mouse Model of Alzheimer's Disease

Gintonin is a novel ginseng-derived lysophosphatidic acid (LPA) receptor ligand. Oral administration of gintonin ameliorates learning and memory dysfunctions in Alzheimer's disease (AD) animal models. The brain cholinergic system plays a key role in cognitive functions. The brains of AD patients show a reduction in acetylcholine concentration caused by cholinergic system impairments. However, little is known about the role of LPA in the cholinergic system. In this study, we used gintonin to investigate the effect of LPA receptor activation on the cholinergic system in vitro and in vivo using wild-type and AD animal models. Gintonin induced [Ca(2+)]i transient in cultured mouse hippocampal neural progenitor cells (NPCs). Gintonin-mediated [Ca(2+)]i transients were linked to stimulation of acetylcholine release through LPA receptor activation. Oral administration of gintonin-enriched fraction (25, 50, or 100 mg/kg, 3 weeks) significantly attenuated scopolamine-induced memory impairment. Oral administration of gintonin (25 or 50 mg/kg, 2 weeks) also significantly attenuated amyloid-β protein (Aβ)-induced cholinergic dysfunctions, such as decreased acetylcholine concentration, decreased choline acetyltransferase (ChAT) activity and immunoreactivity, and increased acetylcholine esterase (AChE) activity. In a transgenic AD mouse model, long-term oral administration of gintonin (25 or 50 mg/kg, 3 months) also attenuated AD-related cholinergic impairments. In this study, we showed that activation of G protein-coupled LPA receptors by gintonin is coupled to the regulation of cholinergic functions. Furthermore, this study showed that gintonin could be a novel agent for the restoration of cholinergic system damages due to Aβ and could be utilized for AD prevention or therapy.