Protopanaxadiols Eliminate Behavioral Impairments and Mitochondrial Dysfunction in Parkinson's Disease Mice Model.

Currently, there are no effective therapies to cure Parkinson's disease (PD), which is the second most common neurodegenerative disease primarily characterized by motor dysfunction and degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc). Protopanaxadiols (PPDs), including 20 (R)- protopanaxadiol (R-PPD) and 20 (S)- protopanaxadiol (S-PPD), are main metabolites of ginsenosides. The role of ginsenosides in neurodegenerative diseases has been thoroughly studied, however, it is unknown whether PPDs can attenuate behavioral deficits and dopaminergic neuron injury in PD model mice to date. Here, we administered PPDs to MPTP-induced PD model mice and monitored the effects on behavior and dopaminergic neurons to investigate the effects of R-PPD and S-PPD against PD. Our results showed that R-PPD and S-PPD (at a dose of 20 mg/kg, i.g.) treatment alleviated MPTP (30 mg/kg, i.p.) induced behavioral deficits. Besides, R-PPD and S-PPD protected MPP+-induced neuron injury and mitochondrial dysfunction, and reduced the abnormal expression of Cyt C, Bax, caspase-3 and Bcl-2. These findings demonstrate that R-PPD and S-PPD were potentially useful to ameliorate PD.

Pharmacokinetics and pharmacodynamics of Rh2 and aPPD ginsenosides in prostate cancer: a drug interaction perspective.

Ginsenoside Rh2 and its aglycon (aPPD) are one of the major metabolites from Panax ginseng. Preclinical studies suggest that Rh2 and aPPD have antitumor effects in prostate cancer (PCa). Our aims in this review are (1) to describe the pharmacokinetic (PK) properties of Rh2 and aPPD ginsenosides; 2) to provide an overview of the preclinical findings on the use of Rh2 and aPPD in the treatment of PCa; and (3) to highlight the mechanisms of its PK and pharmacodynamic (PD) drug interactions. Increasing evidence points to the potential efficacy of Rh2 or aPPD for PCa treatment. Based on the laboratory studies, Rh2 or aPPD combinations revealed an additive or synergistic interaction or enhanced sensitivity of anticancer drugs toward PCa. This review reveals that enhanced anticancer activities were demonstrated in preclinical studies through interactions of Rh2 and/or aPPD with the proteins related to PK (e.g., cytochrome P450 enzymes, transporters) or PD of the other anticancer drugs or PCa signaling pathways. In conclusion, combining Rh2 or aPPD with anti-prostate cancer drugs leads to PK or PD interactions which could facilitate either therapeutically beneficial or toxic effects.

Cycloastragenol, a Triterpenoid Saponin, Regulates Oxidative Stress, Neurotrophic Dysfunctions, Neuroinflammation and Apoptotic Cell Death in Neurodegenerative Conditions.

Here, we have unveiled the effects of cycloastragenol against Aß (Amyloid-beta)-induced oxidative stress, neurogenic dysfunction, activated mitogen-activated protein (MAP) kinases, and mitochondrial apoptosis in an Aß-induced mouse model of Alzheimer's disease (AD). The Aß-induced mouse model was developed by the stereotaxic injection of amyloid-beta (5 µg/mouse/intracerebroventricular), and cycloastragenol was given at a dose of 20 mg/kg/day/p.o for 6 weeks daily. For the biochemical analysis, we used immunofluorescence and Western blotting. Our findings showed that the injection of Aß elevated oxidative stress and reduced the expression of neurogenic markers, as shown by the reduced expression of brain-derived neurotrophic factor (BDNF) and the phosphorylation of its specific receptor tropomyosin receptor kinase B (p-TrKB). In addition, there was a marked reduction in the expression of NeuN (neuronal nuclear protein) in the Aß-injected mice brains (cortex and hippocampus). Interestingly, the expression of Nrf2 (nuclear factor erythroid 2-related factor 2), HO-1 (heme oxygenase-1), p-TrKB, BDNF, and NeuN was markedly enhanced in the Aß + Cycloastragenol co-treated mice brains. We have also evaluated the expressions of MAP kinases such as phospho c-Jun-N-terminal kinase (p-JNK), p-38, and phospho-extracellular signal-related kinase (ERK1/2) in the experimental groups, which suggested that the expression of p-JNK, p-P-38, and p-Erk were significantly upregulated in the Aß-injected mice brains; interestingly, these markers were downregulated in the Aß + Cycloastragenol co-treated mice brains. We also checked the expression of activated microglia and inflammatory cytokines, which showed that cycloastragenol reduced the activated microglia and inflammatory cytokines. Moreover, we evaluated the effects of cycloastragenol against mitochondrial apoptosis and memory dysfunctions in the experimental groups. The findings showed significant regulatory effects against apoptosis and memory dysfunction as revealed by the Morris water maze (MWM) test. Collectively, the findings suggested that cycloastragenol regulates oxidative stress, neurotrophic processes, neuroinflammation, apoptotic cell death, and memory impairment in the mouse model of AD.

Cycloastragenol protects against glucocorticoid-induced osteogenic differentiation inhibition by activating telomerase.

Glucocorticoid-induced osteoporosis (GIOP) that is mainly featured as low bone density and increased risk of fracture is prone to occur with the administration of excessive glucocorticoids. Cycloastragenol (CAG) has been verified to be a small molecule that activates telomerase. Studied showed that up-regulated telomerase was associated with promoting osteogeneic differentiation, so we explored whether CAG could promote osteogenic differentiation to protect against GIOP and telomerase would be the target that CAG exerted its function. Our results demonstrated that CAG prominently increased the ALP activity, mineralization, mRNA of runt-related transcription factor 2, osteocalcin, osteopontin, collagen type I in both MC3T3-E1 cells and dexamethasone (DEX)-treated MC3T3-E1 cells. CAG up-regulated telomerase reverse transcriptase and the protective effect of CAG was blocked by telomerase inhibitor TMPyP4. Moreover, CAG improved bone mineralization in DEX-induced bone damage in a zebrafish larvea model. Therefore, the study showed that CAG could alleviate the osteogenic differentiation inhibition induced by DEX in vitro and in vivo, and CAG might be considered as a candidate drug for the treatment of GIOP.

Ginsenoside 20(S)-protopanaxadiol attenuates depressive-like behaviour and neuroinflammation in chronic unpredictable mild stress-induced depressive rats.

20 (S)-protopanaxadiol (PPD) possesses a variety of biological activities, including antioxidant, antifatigue and anti-inflammatory properties. This study was aimed to investigate the antidepressant-like effects of PPD and potential mechanisms in rats exposed to chronic unpredictable mild stress (CUMS) model. Results showed that chronic treatment with PPD for 14 days ameliorated depressive-like behaviour, as indicated by the increase in sucrose preference in the sucrose preference test and decrease in immobility in the forced swim test and tail suspension test. In addition, PPD decreased the elevated levels of CORT and proinflammatory cytokines (IL-6, IL-1ß and TNF-α) in the serum and neurotransmitters (5-HT and NE) in the hippocampus and PFC induced by CUMS. PPD suppressed the microglial activation in the DG induced by CUMS. Furthermore, our results suggested that rats treated with PPD displayed decreased iNOS, COX2, cleaved-caspase3, cleaved-caspase9, Bax, Bcl-2, and ac-p65 levels and increased Sirt1 levels in the hippocampus. In conclusion, this study indicated that PPD exerts promising antidepressant-like effects in CUMS rats that are mediated in part through alterations in the dysfunction of the HPA axis, the normalization of the levels of neurotransmitters, and the suppression of neuronal apoptosis and neuroinflammation, possibly through the regulation of the SIRT1/NF-kB signalling pathway.

Dammarane sapogenins attenuates stress-induced anxiety-like behaviors by upregulating ERK/CREB/BDNF pathways.

Dammarane sapogenins (DS), an extract derived from ginseng by alkaline hydrolysis of total ginsenosides, possesses high pharmacological activity and higher bioavailability than ginsenosides. The present study was designed to investigate the anxiolytic-like effects of DS in a mouse model of chronic social defeat stress (CSDS). DS (40 and 80 mg/kg) significantly ameliorated social avoidance and anxiety-like behavior in four test models of CSDS, showing increased time in the interaction zone in the social interaction test and in the center of the field in the open field test, an increased percentage of entries and open arm time in the elevated plus maze, and reduced latency to eat in the novelty-suppressed feeding test. Biochemical analyses showed that DS significantly reduced serum corticosterone levels and increased brain concentration of neurotransmitter 5-HT and noradrenaline in CSDS mice. Treatment with DS significantly upregulated BDNF (brain-derived neurotrophic factor), p-CREB/CREB and p-ERK1/2/ERK1/2 protein expression in the hippocampus and prefrontal cortex of CSDS mice. Collectively, these results suggest that DS exerts anxiolytic-like effects in CSDS model mice and the action is mediated, at least in part, by modulating the HPA (hypothalamic-pituitary-adrenal) axis and monoamine neurotransmitter levels, and via ERK/CREB/BDNF signaling pathway.

Cycloastragenol upregulates SIRT1 expression, attenuates apoptosis and suppresses neuroinflammation after brain ischemia.

Cycloastragenol (CAG) is the active form of astragaloside IV isolated from Astragalus Radix, which displays multiple pharmacological effects. Silent information regulator 1 (SIRT1), a class III histone deacetylase, has been shown to play an important role in neuroprotection against cerebral ischemia. In this study, we investigated whether CAG protected against ischemic brain injury and, if so, whether the beneficial effects were associated with the regulation of SIRT1 in the ischemic brain. Mice were subjected to 45 min of middle cerebral artery occlusion (MCAO) followed by reperfusion. CAG (5, 10, 20 mg/kg) was injected intraperitoneally at the onset of reperfusion, 12 h later and then twice daily for up to three days. CAG dose-dependently reduced brain infarct volume, significantly ameliorated functional deficits, and prevented neuronal cell loss in MCAO mice. Meanwhile, CAG significantly reduced matrix metalloproteinase-9 activity, prevented tight junction degradation and subsequently ameliorated blood-brain barrier disruption. Moreover, CAG significantly upregulated SIRT1 expression in the ischemic brain but did not directly activate its enzymatic activity. Concomitant with SIRT1 upregulation, CAG reduced p53 acetylation and the ratio of Bax to Bcl-2 in the ischemic brain. CAG also inhibited NF-κB p65 nuclear translocation. As a result, CAG suppressed the mRNA expression of pro-inflammatory cytokines, including TNF-α and IL-1ß, and inhibited the activation of microglia and astrocytes in the ischemic brain. Our findings suggest that CAG is neuroprotective against ischemic brain injury in mice and that its beneficial effect may involve SIRT1 upregulation and the inhibition of apoptosis and neuroinflammation in the ischemic brain.

Ginsenoside metabolite 20(S)-protopanaxatriol from Panax ginseng attenuates inflammation-mediated NLRP3 inflammasome activation.

ETHNOPHARMACOLOGICAL RELEVANCE: Panax ginseng C.A. Meyer (Araliaceae), has been used in traditional medicine for preventive and therapeutic purposes in Asian countries. One of the active ginsenoside metabolites, 20(S)-Protopanaxatriol (PPT), has been associated with diverse pharmacological effects, including anti-inflammatory properties. AIM OF THE STUDY: Although the capacity of PPT as an anti-inflammatory agent has been studied, this study aimed to explore the intrinsic mechanism of PPT in regulating inflammasome activation-mediated inflammatory responses in experimental models. MATERIALS AND METHODS: Lipopolysaccharide (LPS)-primed peritoneal macrophages in vitro was used to study the role of PPT on inflammasome activation. LPS-induced septic shock and monosodium urate (MSU)-induced murine peritonitis models were employed for in vivo evaluations. RESULTS: PPT attenuated NLRP3 inflammasome activation and also reduced ASC oligomerization, leading to attenuation of interleukin (IL)-1ß secretion. Further, PPT inhibited IL-1ß secretion in both LPS-induced septic shock and MSU-induced mouse peritonitis models. CONCLUSIONS: This study revealed that ginsenoside metabolite PPT, inhibits inflammation-mediated inflammasome activation and supported the traditional use of ginseng in treating various inflammatory disorders.

Antidepressant-like effects of 20(S)-protopanaxadiol in a mouse model of chronic social defeat stress and the related mechanisms.

20(S)-Protopanaxadiol (PPD) is a basic aglycone of the dammarane triterpenoid saponins and exerts antidepressant-like effects on behaviour in the forced swimming test (FST) and tail suspension test (TST) and in rat olfactory bulbectomy depression models. However, the antidepressant effects of PPD have not been studied thoroughly. The objective of the present study was first to investigate the effect of PPD on depression behaviours induced by chronic social defeat stress (CSDS) in mice. The results showed that CSDS was effective in producing depression-like behaviours in mice, as indicated by decreased responses in the social interaction test, sucrose preference test, TST, and FST, and that this effect was accompanied by noticeable alterations in the levels of oxidative markers (superoxide dismutase, catalase, and lipid peroxidation) and monoamines (5-HT and NE) in the hippocampus and serum corticosterone levels. Additionally, western blot analysis revealed that CSDS exposure significantly downregulated BDNF, p-TrkB/TrkB, p-Akt/Akt, and p-mTOR/mTOR protein expression in the hippocampus. Remarkably, chronic PPD treatment significantly ameliorated these behavioral and biochemical alterations associated withCSDS-induced depression. Our results suggest that PPD exerts antidepressant-like effects in mice with CSDS-induced depression and that this effect may be mediated by the normalization of neurotransmitter and corticosterone levels and the alleviation of oxidative stress, as well as the enhancement of the PI3K/Akt/mTOR-mediated BDNF/TrkB pathway.

Inhibition of NLRP3 inflammasome-mediated pyroptosis in macrophage by cycloastragenol contributes to amelioration of imiquimod-induced psoriasis-like skin inflammation in mice.

Psoriasis is a common chronic inflammatory skin disease, and the infiltrated macrophages in psoriatic skin lesions play a key role in the progression of this uncontrolled cutaneous inflammation. However, the current therapeutic strategies for patients with psoriasis are not satisfactory. Here, we report that cycloastragenol (CAG), a natural active small compound isolated from Astragalus membranaceus, significantly ameliorated imiquimod (IMQ)-induced psoriasiform dermatitis in mice by targeting proinflammatory macrophages. CAG significantly reduced the clinical scores, decreased the epidermal thickness, and ameliorated the deteriorating histopathology observed in IMQ-induced mice. CAG treatment specifically reduced the dermal infiltration of macrophages, rather than of dendritic cells, neutrophils, or T lymphocytes, into psoriatic skin. CAG dose-dependently decreased the level of proinflammatory cytokines, including IL-1ß, TNF-α and IL-6, in murine psoriatic skin and serum, as well as in IMQ-stimulated, bone-marrow-derived macrophages. When compared to the control group, CAG significantly decreased IMQ-triggered NLRP3 inflammasome activation and gasdermin D-mediated cell pyroptosis in these proinflammatory macrophages. CAG also suppressed the assembly of the NLRP3 inflammasome complex. Taken together, the results show that CAG selectively modulates macrophage function by inhibiting NLRP3 inflammasome-mediated pyroptosis to ameliorate IMQ-induced psoriasis-like skin inflammation in mice. Our findings also identify an effective drug candidate for the treatment of psoriasis.

Protopanaxadiol alleviates obesity in high-fat diet-fed mice via activation of energy-sensing neuron in the paraventricular nucleus of hypothalamus.

Obesity is one of the most important health problems worldwide. Panax ginseng has been reported to exert anti-obesity effect. However, the active constituents and the underlying mechanism remained uncertain. This study uncovered the anti-obesity effect of protopanaxadiol (PPD) and its potential mechanism. To investigate the anti-obesity effect of PPD, high-fat diet induced obesity (DIO) C57BL/6 mice were treated with PPD by both intraperitoneal injection (i.p.) and oral administration. Body weight and food intake were recorded. Energy expenditure was measured by CLAMS metabolic cages. For mechanism study, C-Fos in the hypothalamus of the mice was stained following the intracerebroventricular (i.c.v.) injection of PPD. Our results showed that with both injection and feeding, PPD reduced body weight, inhibited food intake, increased energy expenditure and improved liver damage in DIO mice. Mechanistically, i.c.v. injection of PPD inhibited feeding and increased C-Fos expression in paraventricular nucleus of the hypothalamus (PVH). The results suggest that PPD may reduce body weight of DIO mice via the activation of PVH neurons and PPD is a potential therapeutic candidate for the treatment of obesity.

LC-MS/MS determination of ginsenoside compound K and its metabolite 20 (S)-protopanaxadiol in human plasma and urine: applications in a clinical study.

AIM: Ginsenoside compound K (CK) is considered to be a potential therapeutic drug for rheumatoid arthritis because of its good anti-inflammatory activity. The purpose of this work was to establish a rapid, sensitive and specific method for determination of CK and its active metabolite 20(S)-protopanaxadiol (20(S)-PPD). Materials & methods: The analytes and internal standards were extracted by liquid-liquid extraction. Then, were separated by high performance liquid phase and determined by triple quadrupole mass spectrometry. RESULTS: A LC-MS/MS using liquid-liquid extraction was developed for determining CK over the concentration range 1.00-1002.00 ng/ml and 0.15-54.30 ng/ml for 20(S)-PPD. The lower limits of quantification for CK and 20(S)-PPD were 1.00 and 0.15 ng/ml, respectively. CONCLUSION: This method was successfully validated for detecting both CK and 20(S)-PPD in the human plasma and urine, and was proved to be suitable for the pharmacokinetic study of CK in healthy Chinese volunteers. CLINICAL TRIAL REGISTRATION NUMBER: ChiCTR-TRC-14004824.

Co-administration of 20(S)-protopanaxatriol (g-PPT) and EGFR-TKI overcomes EGFR-TKI resistance by decreasing SCD1 induced lipid accumulation in non-small cell lung cancer.

BACKGROUND: Non-small cell lung cancer (NSCLC) patients with sensitive epidermal growth factor receptor (EGFR) mutations are successfully treated with EGFR tyrosine kinase inhibitors (EGFR-TKIs); however, resistance to treatment inevitably occurs. Given lipid metabolic reprogramming is widely known as a hallmark of cancer and intimately linked with EGFR-stimulated cancer growth. Activation of EGFR signal pathway increased monounsaturated fatty acids (MUFA) and lipid metabolism key enzyme Stearoyl-CoA Desaturase 1 (SCD1) expression. However the correlation between EGFR-TKI resistance and lipid metabolism remains to be determined. METHODS: In this study the differences in lipid synthesis between paired TKI-sensitive and TKI-resistant patient tissues and NSCLC cell lines were explored. Oleic acid (OA, a kind of MUFA, the SCD1 enzymatic product) was used to simulate a high lipid metabolic environment and detected the affection on the cytotoxic effect of TKIs (Gefitinib and osimertinib) in cell lines with EGFR-activating mutations. (20S)-Protopanaxatriol (g-PPT), an aglycone of ginsenosides, has been reported to be an effective lipid metabolism inhibitor, was used to inhibit lipid metabolism. Additionally, synergism in cytotoxic effects and signal pathway activation were evaluated using CCK-8 assays, Western blotting, flow cytometry, Edu assays, plate clone formation assays and immunofluorescence. Furthermore, two xenograft mouse models were used to verify the in vitro results. RESULTS: Gefitinib-resistant cells have higher lipid droplet content and SCD1 expression than Gefitinib-sensitive cells in both NSCLC cell lines and patient tissues. Additionally oleic acid (OA, a kind of MUFA, the SCD1 enzymatic product) abrogates the cytotoxic effect of both Gefitinib and osimertinib in cell lines with EGFR-activating mutations. As a reported effective lipid metabolism inhibitor, g-PPT significantly inhibited the expression of SCD1 in lung adenocarcinoma cells, and then down-regulated the content of intracellular lipid droplets. Combined treatment with Gefitinib and g-PPT reverses the resistance to Gefitinib and inhibits the activation of p-EGFR and the downstream signaling pathways. CONCLUSIONS: Our findings uncover a link between lipid metabolic reprogramming and EGFR-TKI resistance, confirmed that combination target both EGFR and abnormal lipid metabolism maybe a promising therapy for EGFR-TKI resistance and highlighting the possibility of monitoring lipid accumulation in tumors for predicting drug resistance.

Ginsenoside 20(S)-protopanaxadiol inhibits triple-negative breast cancer metastasis in vivo by targeting EGFR-mediated MAPK pathway.

Metastasis is the primary cause of cancer recurrence and cancer related mortality in triple-negative breast cancer (TNBC). EGFR overexpression is in 50-75% TNBC and EGFR-mediated signaling has potential as an attractive therapeutic target in some specific subtypes of breast cancer due to its significant association with tumor metastasis and poor prognosis. Therefore, identification of promising therapeutic strategies targeting EGFR with higher specificity toward cancer metastasis is urgently needed. 20(S)-protopanaxadiol (PPD), one of the major active metabolites from Panax ginseng, has been widely reported to possess pleiotropic anticancer activities in various cancers. In this study, we investigated the effect of PPD against cancer metastasis and the related molecular mechanisms in TNBC in vitro and in vivo. PPD (>30 µM) suppressed cell proliferation by arresting cell cycle in G0/1 phase and triggering cells apoptosis as shown by cell viability assay, flow cytometry analysis and colony formation assay, whereas lower dose of PPD (<20 µM) decreased metastatic potential of MDA-MB-231 and SUM159 cells through direct inhibition of cell adhesion, motility and invasiveness. In TNBC xenograft and syngeneic models, PPD treatment markedly decreased tumor growth and lung metastasis. PPD reversed epithelial-mesenchymal transition (EMT), decreased the expression and activity of matrix metalloproteinases (MMPs) while increased the expression of tissue inhibitors of metalloproteinases (TIMPs) as shown by Western blot and gelatin zymography. Cell signaling pathways that control the expression or activation of these processes were investigated by Western blot and ELISA assay. PPD treatment reduced the phosphorylation of EGFR and down-regulated the activation ERK1/2, p38 and JNK signaling, which was further validated by using the agonists or inhibitors of EGFR and MAP kinases family. Collectively, these findings suggest that PPD holds therapeutic potential against the tumor metastasis of TNBC via targeting EGFR-mediated MAPK pathway.

Protective effects of protopanaxatriol on acute liver injury induced by concanavalin A.

The purpose of this study was to explore the protective effect of protopanaxatriol (PPT) on acute liver injury induced by concanavalin A (ConA). In this study, mice were randomly separated into four groups. The first group received PBS (i.v.). The second group was given PPT (50 mg/kg body weight, i.p.) for 3 days before PBS (i.v.) injection. The third group received ConA (15 mg/kg body weight, i.v.). The fourth group was administered PPT (50 mg/kg body weight, i.p.) for 3 days before ConA (i.v.) injection. The serum levels of ALT and AST were detected after 20 h of ConA injection. The pathological changes of liver were observed by H/E staining. The expression of inflammatory factors was measured by ELISA and qRTPCR, and the changes of the signaling pathway were detected by western blot. Histopathological changes and blood transaminase elevation indicated significant liver injury after ConA injection. However, PPT pretreatment obviously reversed these changes. The ELISA and qRT-PCR results indicated that PPT preconditioning significantly inhibited the production of inflammatory factors. In addition, this inhibitory effect of PPT was mainly mediated by regulation of the nuclear factor-κB (NF-κB) signaling pathway. The active ingredient of ginseng, PPT, exerts an obvious protective effect on acute liver injury caused by ConA through inhibiting the inflammatory response.

Antidepressant effects of dammarane sapogenins in chronic unpredictable mild stress-induced depressive mice.

Depression is a common, dysthymic, and psychiatric disorder, resulting in enormous social and economic burden. Dammarane sapogenins (DS), an active fraction from oriental ginseng, has shown antidepressant-like effects in chronic restraint rats and sleep interruption-induced mice, and the present study aimed to further confirm the antidepressant effects of DS in a model of chronic unpredictable mild stress (CUMS) and to explore the underlying mechanism. Oral administration of DS (20, 40, and 80 mg/kg) markedly improved depressant-like behaviors, increasing the sucrose intake in the sucrose preference test and reducing the latency in the novelty-suppressed feeding test, and decreasing the immobility time in both the tail suspension and forced swimming tests, compared with the CUMS mice. Biochemical analysis of brain tissue and serum showed that DS treatment restored the decreased hippocampal neurotransmitter concentrations of serotonin, dopamine, norepinephrine (noradrenaline), and gamma-aminobutyric acid, and decreased the elevated of serum hormone levels (corticotrophin releasing factor, adrenocorticotrophic hormone, and corticosterone) induced by CUMS. Our findings confirm that DS exerts an antidepressant-like effect in the CUMS model of depression in mice, and suggest it may be mediated by regulation of neurotransmitters and hypothalamic-pituitary-adrenal axis.

Neuroprotective effects of 20(S)-protopanaxatriol (PPT) on scopolamine-induced cognitive deficits in mice.

20(S)-protopanaxatriol (PPT), one of the ginsenosides from Panax ginseng, has been reported to have neuroprotective effects and to improve memory. The present study was designed to investigate the protective effect of PPT on scopolamine-induced cognitive deficits in mice. Male Institute of Cancer Research mice were pretreated with 2 different doses of PPT (20 and 40 µmol/kg) for 27 days by intraperitoneal injection, and scopolamine (0.75 mg/kg) was injected intraperitoneally for 9 days to induce memory impairment. Thirty minutes after the last pretreatment, the locomotor activity was firstly examined to evaluate the motor function of mice. Then, memory-related behaviors were evaluated, and the related mechanism was further researched. It was founded that PPT treatment significantly reversed scopolamine-induced cognitive impairment in the object location recognition experiment, the Morris water maze test, and the passive avoidance task, showing memory-improving effects. PPT also significantly improved cholinergic system reactivity and suppressed oxidative stress, indicated by inhibition of acetylcholinesterase activity, elevation of acetylcholine levels, increasing superoxide dismutase activity and lowering levels of malondialdehyde in the hippocampus. In addition, the expression levels of Egr-1, c-Jun, and cAMP responsive element binding in the hippocampus were significantly elevated by PPT administration. These results suggest that PPT may be a potential drug candidate for the treatment of cognitive deficit in Alzheimer's disease.

Ruscogenin suppressed the hepatocellular carcinoma metastasis via PI3K/Akt/mTOR signaling pathway.

BACKGROUND: Hepatocellular carcinoma (HCC) is the third-leading cause of cancer-related mortality with poor prognosis and treatment. More effective strategies should be studied in HCC. METHODS: After treated with ruscogenin, the cell proliferation was assessed by CCK-8 method. Cell migration and invasion were estimated using wound healing and transwell assays. Pathological changes of lung tissue were observed by HE staining and IHC methods. MMP-2, MMP-9, uPA, VEGF and HIF-1α levels were measured using ELISA, RT-qPCR and WB tests. PI3K/Akt/mTOR pathway related molecules were detected using WB analysis. RESULTS: The results indicated the hypotoxicity of ruscogenin. Meanwhile, ruscogenin showed obvious interruption on the cancer cell migration and invasion, and inhibition on the metastatic foci in pulmonary tissue. Significantly, ruscogenin decreased the levels of MMP-2, MMP-9, uPA, VEGF and HIF-1α, down-regulated the phosphorylation of Akt, mTOR. CONCLUSION: The present study indicated a novel use of ruscogenin in suppressing HCC metastasis by reducing the expression of MMP-2, MMP-9, uPA, VEGF and HIF-1α via regulating the PI3K/Akt/mTOR signaling pathway.

Cycloastragenol improves hepatic steatosis by activating farnesoid X receptor signalling.

Non-alcoholic fatty liver disease (NAFLD) has become a global health problem. However, there is no approved therapy for NAFLD. Farnesoid X receptor (FXR) is a potential drug target for treatment of NAFLD. In an attempt to screen FXR agonists, we found that cycloastragenol (CAG), a natural occurring compound in Astragali Radix, stimulated FXR transcription activity. In animal studies, we demonstrated that CAG treatment resulted in obvious reduction of high-fat diet induced lipid accumulation in liver accompanied by lowered blood glucose, serum triglyceride levels and hepatic bile acid pool size. The stimulation of FXR signalling by CAG treatment in DIO mice was confirmed via gene expression and western blot analysis. Molecular docking data further supported the interaction of CAG and FXR. In addition, CAG alleviated hepatic steatosis in methionine and choline deficient L-amino acid diet (MCD) induced non-alcoholic steatohepatitis (NASH) mice. Our data suggest that CAG ameliorates NAFLD via the enhancement of FXR signalling.

A highly sensitive HPLC-MS/MS method for quantification of 20(S)-protopanaxadiol in human plasma and its application in phase IIa clinical trial of a novel antidepressant agent.

A highly sensitive HPLC-MS/MS assay method was established to quantify 20(S)-protopanaxadiol (PPD) in human plasma with dexamethasone as an internal standard. The electrospray ion mass spectrometry (ESI-MS) was operated under the multiple reactions monitoring mode (MRM) using positive ion mode. PPD was extracted from 500µL plasma samples by liquid-liquid extraction then separated by a C18 analytical column with gradient elution. The concentration of PPD could be determined by this HPLC-MS/MS method over the range of 0.05-20ng/mL with the lower limit of quantification (LLOQ) of 0.05ng/mL. The method was successfully applied to phase IIa clinical trial of Yuxintine (PPD capsule) in which plasma samples of 87 subjects were analyzed following 6 weeks of oral administration of placebo or PPD capsules in 5 different doses. In this study, the measured concentration was linearly related to the oral dosage with R=0.9901. The minimum and maximum values of measured concentration were 0.06 and 11.60ng/mL, respectively. In addition, plasma concentrations of PPD in depression patients were reported for the first time in our study.