Rare ginsenosides: A unique perspective of ginseng research.

BACKGROUND: Rare ginsenosides (Rg3, Rh2, C-K, etc.) refer to a group of dammarane triterpenoids that exist in low natural abundance, mostly produced by deglycosylation or side chain modification via physicochemical processing or metabolic transformation in gut, and last but not least, exhibited potent biological activity comparing to the primary ginsenosides, which lead to a high concern in both the research and development of ginseng and ginsenoside-related nutraceutical and natural products. Nevertheless, a comprehensive review on these promising compounds is not available yet. AIM OF REVIEW: In this review, recent advances of Rare ginsenosides (RGs) were summarized dealing with the structurally diverse characteristics, traditional usage, drug discovery situation, clinical application, pharmacological effects and the underlying mechanisms, structure-activity relationship, toxicity, the stereochemistry properties, and production strategies. KEY SCIENTIFIC CONCEPTS OF REVIEW: A total of 144 RGs with diverse skeletons and bioactivities were isolated from Panax species. RGs acted as natural ligands on some specific receptors, such as bile acid receptors, steroid hormone receptors, and adenosine diphosphate (ADP) receptors. The RGs showed promising bioactivities including immunoregulatory and adaptogen-like effect, anti-aging effect, anti-tumor effect, as well as their effects on cardiovascular and cerebrovascular system, central nervous system, obesity and diabetes, and interaction with gut microbiota. Clinical trials indicated the potential of RGs, while high quality data remains inadequate, and no obvious side effects was found. The stereochemistry properties induced by deglycosylation at C (20) were also addressed including pharmacodynamics behaviors, together with the state-of-art analytical strategies for the identification of saponin stereoisomers. Finally, the batch preparation of targeted RGs by designated strategies including heating or acid/ alkaline-assisted processes, and enzymatic biotransformation and biosynthesis were discussed. Hopefully, the present review can provide more clues for the extensive understanding and future in-depth research and development of RGs, originated from the worldwide well recognized ginseng plants.

Electroacupuncture Ameliorates Depression-Like Behaviors Comorbid to Chronic Neuropathic Pain via Tet1-Mediated Restoration of Adult Neurogenesis.

Although electroacupuncture (EA) stimulation is a widely used therapy for chronic pain and comorbid psychiatric disorders, its long-term effects on chronic neuropathic pain-induced depression and the underlying mechanisms remain elusive. In the present study, we found that EA stimulation was able to restore adult neurogenesis in the ventral dentate gyrus (DG), by both increasing neuronal differentiation and restoring the normal morphology of newborn dendrites, in mice with spared nerve injury surgery. By ablating the Nestin+ neural stem cells (NSCs) via diphtheria toxin fragment A expression, we further proved that neurogenesis in the ventral DG was crucial to the long-term, but not the immediate antidepressant effect of EA, nor was it associated with nociception. Furthermore, we found that the restoration of neurogenesis was dependent on Tet1-mediated epigenetic modification upon EA treatment. Tet1 could bind to the promoter of the Prox1 gene, thus catalyzing its demethylation and facilitating its expression, which finally contributed to the restoration of neurogenesis and amelioration of depression-like behaviors induced by chronic neuropathic pain. Thus, we conclude that EA stimulation restores inhibited Tet1 expression in hippocampal NSCs of mice with chronic neuropathic pain, and increased Tet1 expression ameliorates hypermethylation of Prox1 and restores normal adult neurogenesis in the ventral DG, which contributes to the long-term antidepressant effect of EA.

[New method for green extraction of ginsenosides based on mechanochemically-assisted extraction and deep eutectic solvents].

Ginsenosides are the main active ingredients in ginseng. Studies have shown that ginsenosides have anti-virus, anti-tumor, anti-aging, nootropic, cardiovascular diseases-protecting, and other pharmacological activities. Thus, the development and utilization of ginsenosides have persistently attracted much attention. At present, the extraction of ginsenosides is mainly based on organic solvents, and there are relatively few studies on their green extraction. In this study, different deep eutectic solvents(DESs) were synthesized by heating and stirring method, combined with an emerging technology, mechanochemically-assisted extraction(MCAE), to extract ginsenosides in a green way. Six parameters that might affect the extraction effect were optimized to determine the optimal conditions, and the method validation was conducted. The new established method was compared with a commonly used extraction method(ultrasound-assisted extraction using 70% ethanol) to evaluate its extraction efficiency. The results revealed that the optimal extraction conditions of DES-MCAE were that the volume ratio of DES3(choline chloride∶urea 1∶2) and water in the extraction solvent was 6∶4, and the liquid ratio and the linear vibration speed were 0.05 g·mL~(-1) and 4.0 m·s~(-1); the extraction was performed twice, 40 s each. With only 80 s extraction, the extraction rate of this method was 36.22% higher than that of ultrasoun-dassisted extraction using 70% ethanol. In this study, a DESs-based pretreatment method for ginsenosides was established and its rapid, green and efficient extraction was realized, which provided new ideas and methods for further research on green extraction of other active ingredients from Chinese medicine.

Limonoids From the Genus Melia (Meliaceae): Phytochemistry, Synthesis, Bioactivities, Pharmacokinetics, and Toxicology.

Limonoids, as the vital bioactive chemical compounds in genus Melia plants, have attracted significant attention owing to their exclusive structural characteristics and remarkable biological activity. These compounds can be usually classified into two categories, including the ring-intact group and the ring-C-seco group. Benefiting from the development of separation and analysis technology, more than 200 limonoids have been isolated and identified from this genus. There is growing evidence that limonoids from genus Melia possess diverse pharmacological activities, especially anti-cancer effects, insecticidal activities, and anti-botulism effects. Toosendanin, one of the paramount limonoids, was considered as the pivotal bioactive marker in two medicinal herbs, including Melia toosendan Sieb. et Zucc and Melia azedarach L. In particular, limonoids are found to exhibit non-negligible toxic effects, a finding which needs further research. Besides this, the lack of clinical research data seriously hinders its further development and utilization, and necessary clinical trials should be taken into consideration. In this review, we systematically summarized the phytochemical compounds and their synthesis methods, pharmacological activities, and the structure-activity relationship, pharmacokinetics, and toxicology of genus Melia-derived limonoids. We believe that this up-to-date review could provide scientific evidence for the application of limonoids as agents beneficial to health in future clinical practice.

Traditional uses, botany, phytochemistry, pharmacology, separation and analysis technologies of Euonymus alatus (Thunb.) Siebold: A comprehensive review.

ETHNOPHARMACOLOGICAL RELEVANCE: Euonymus alatus (Thunb.) Siebold (E. alatus), a well-known medicinal plant, has been widely used thousands of years in China for the treatment of various diseases such as urticaria, dysmenorrhea, wound, dysentery, blood stasis, rheumatism and arthritis. Due to the extensive application of E. alatus in the fields of ethnopharmacological usage, the pharmaceutical researches of E. alatus keeps deepening. AIM OF THE STUDY: This paper reviewed and summarized the integrated research progress of this medicinal plant. A comprehensive summary and comparison of traditional usages, botany, phytochemistry, pharmacology, toxicology, separation and analysis technologies of the E. alatus highlight recent scientific advances, which provides new insights into the research and development of this medicinal plant and would be helpful to promote the research situation of underlying pharmacological mechanisms and further utilizations of E. alatus. MATERIAL AND METHODS: Literature survey was carried out via classic books of herbal medicine, PhD. and MSc. Dissertations. Online scientific databases including Pubmed, SciFinder, Science Direct, Scopus, the Web of Science, Google Scholar, China National Knowledge Infrastructure (CNKI) and others were searched up to February 2020 to identify eligible studies. All literatures of the research subject are analyzed and summarized in this review. RESULTS: The E. alatus has been widely used in traditional practice in China, Korea and other Asian Countries. In the study of phytochemistry, more than 230 chemical constituents have been isolated and identified from E. alatus, including sesquiterpenoids, diterpenoids, triterpenoids, flavonoids, phenylpropanoids, lignans, steroids, alkaloids and other compounds. Among them, literature reports show that flavonoids and steroids are the most important bioactive substances found in this plant. A number of researches also have shown that extracts and compounds from E. alatus exert a wide spectrum of pharmacological effects, including antidiabetic effect, anti-tumor effects, anti-inflammatory effects, hepatoprotective effects, antioxidant effects, antibacterial effects, as well as other effects. However, most of the studies without clinical research. Research into plant's toxicological effects has also been limited. In addition, this review also summarizes and compares the separation and analysis technologies of E. alatus. CONCLUSIONS: E. alatus has potential for the treatment of many diseases, especially tumors and diabetes. But many traditional uses of E. alatus have not been validated by current investigations. Additionally, modern studies haven't gone far enough into its pharmacological effects and the corresponding chemical constituents, more efforts should be made to illuminate the underlying mechanisms of E. alatus for treatment of tumors and diabetes. Moreover, the toxicological effects of this plant can be further studied. Currently, there are limited studies on its side effects and toxicological effects, which should provide further guidance for the safety of clinical use.

Ginkgo diterpene lactones inhibit cerebral ischemia/reperfusion induced inflammatory response in astrocytes via TLR4/NF-κB pathway in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Ginkgo biloba L. (Ginkgoaceae) is a traditional Chinese medicine known to treating stroke and other cardio-cerebrovascular diseases for thousands of years in China. Ginkgo diterpene lactones (GDL) attracted much attention because of their neuroprotective properties. AIM OF THE STUDY: To uncover the effects of GDL, which consist of ginkgolide A (GA), ginkgolide B (GB), and ginkgolide K (GK), on ischemic stroke, as well as the underlying molecular mechanisms. MATERIALS AND METHODS: We used middle cerebral artery occlusion/reperfusion (MCAO/R) and oxygen-glucose deprivation/reoxygenation (OGD/R) models mimicking the process of ischemia/reperfusion in vivo and in vitro, respectively. Anticoagulant effects of GDL were investigated on platelet activating factor (PAF), arachidonic acid (AA) and adenosine diphosphate (ADP)-induced platelet aggregation both in vivo and in vitro. We also evaluated the effects of GDL on lipopolysaccharide (LPS)-induced inflammatory response in primary cultured rats' astrocytes. Infarct size, neurological deficit score, and brain edema were measured at 72 h after MCAO. Immunohistochemistry was utilized to analyze neurons necrosis and astrocytes activation. Expression of pro-inflammatory cytokines, including tumor necrotic factor-α (TNF-α) and interleukin-1ß (IL-1ß) were detected using enzyme-linked immunosorbent assay (ELISA) and real time PCR. The levels of toll-like receptor 4 (TLR4) and nuclear factor κB (NF-κB) were assessed by real time PCR or Western blot. RESULTS: Compared with MCAO/R rats, GDL significantly reduced infarct size and brain edema, improved neurological deficit score. Meanwhile, GDL suppressed platelet aggregation, astrocytes activation, pro-inflammatory cytokines releasing, TLR4 mRNA expression and transfer of NF-κB from cytoplasm to nucleus. Furthermore, GDL alleviated OGD/R injury and LPS-induced inflammatory response in primary astrocytes, characterized by promoting cell viability, decreasing lactate dehydrogenase (LDH) activity, and inhibiting IL-1ß and TNF-α releasing. CONCLUSIONS: In summary, GDL attenuate cerebral ischemic injury, inhibit platelet aggregation and astrocytes activation. The anti-inflammatory activity might be associated with the downregulation of TLR4/NF-κB signal pathway. Our present findings provide an innovative insight into the novel treatment of GDL in ischemic stroke therapy.

In silico drug design of inhibitor of nuclear factor kappa B kinase subunit beta inhibitors from 2-acylamino-3-aminothienopyridines based on quantitative structure-activity relationships and molecular docking.

Inhibitor of nuclear factor kappa B kinase subunit beta (IKK-ß), a specific regulator of nuclear factor-κB (NF-κB), is considered a valid target to design novel candidate drugs to treat rheumatoid arthritis and various cancers. In the present study, quantitative structure-activity relationships (QSAR) and molecular docking techniques were used to screen for new IKK-ß inhibitors from a series of 2-acylamino-3-aminothienopyridine analogs. During the two-dimensional QSAR phase, the statistical model partial least square was selected from among two alternatives (r2 = 0.868, q2 (cross-validation) = 0.630). Descriptors with positive or negative contributions were derived from the created model. To build of three-dimensional QSAR models, we used three different fingerprints as analysis precepts for molecular clustering and the subsequent division of training sets and test sets. The best model, which used fingerprint model definition language public keys, was selected for further prediction of the compounds' activities. Favorable physicochemical, structural, electrostatic, and steric properties were derived from the created QSAR models and then used for drug design with an in-house library. Amongst the designed compounds, compounds B01 and B02 showed good predicted activities. Furthermore, after a selecting the protein structure and docking method, docking studies were carried out to reveal the detailed interactions between the ligands and the target protein. Binding affinity was measured and sorted using the value of "-CDOCKER_ENERGY". The high -CDOCKER_ENERGY values of compounds B01 (41.6134 kcal/mol) and B02 (40.1366 kcal/mol) indicated their prominent docking affinities.

Traditional Uses, Botany, Phytochemistry, Pharmacology, Pharmacokinetics and Toxicology of Xanthium strumarium L.: A Review.

Xanthium strumarium L. (Asteraceae) is a common and well-known traditional Chinese herbal medicine usually named Cang-Er-Zi, and has been used for thousands of years in China. The purpose of this paper is to summarize the progress of modern research, and provide a systematic review on the traditional usages, botany, phytochemistry, pharmacology, pharmacokinetics, and toxicology of the X. strumarium. Moreover, an in-depth discussion of some valuable issues and possible development for future research on this plant is also given. X. strumarium, as a traditional herbal medicine, has been extensively applied to treat many diseases, such as rhinitis, nasal sinusitis, headache, gastric ulcer, urticaria, rheumatism bacterial, fungal infections and arthritis. Up to now, more than 170 chemical constituents have been isolated and identified from X. strumarium, including sesquiterpenoids, phenylpropenoids, lignanoids, coumarins, steroids, glycosides, flavonoids, thiazides, anthraquinones, naphthoquinones and other compounds. Modern research shows that the extracts and compounds from X. strumarium possess wide-ranging pharmacological effects, including anti- allergic rhinitis (AR) effects, anti-tumor effects, anti-inflammatory and analgesic effects, insecticide and antiparasitic effects, antioxidant effects, antibacterial and antifungal effects, antidiabetic effects, antilipidemic effects and antiviral effects. However, further research should focus on investigating bioactive compounds and demonstrate the mechanism of its detoxification, and more reasonable quality control standards for X. strumarium should also be established.

Morphine regulates adult neurogenesis and contextual memory extinction via the PKCε/Prox1 pathway.

We have previously reported that the miR-181a/Prox1/Notch1 pathway mediates the effect of morphine on modulating lineage-specific differentiation of adult neural stem/progenitor cells (NSPCs) via a PKCε-dependent pathway, whereas fentanyl shows no such effect. However, the role of the PKCε/Prox1 pathway in mediating drug-associated contextual memory remains unknown. The current study investigated the effect of PKCε/Prox1 on morphine-induced inhibition of adult neurogenesis and drug-associated contextual memory in mice, while the effect of fentanyl was tested simultaneously. By using BrdU labeling, we were able to examine the lineages of differentiated NSPCs in adult DG. PKCε knockout blocked morphine's effects on inducing in vivo astrocyte-preferential differentiation of NSPCs, but did not alter NSPC lineages upon fentanyl treatment. Inhibited adult neurogenesis further resulted in prolonged extinction and enhanced reinstatement of morphine-induced CPP, as well as prolonged extinction of space reference memory indicated by the Morris water maze paradigm. However, after fentanyl administration, no significant changes were found between wild-type and PKCε knockout mice, during either CPP or water maze tasks. When the lentivirus encoding Nestin-promoter-controlled Prox1 cDNA was injected into hippocampi of wildtype and PKCε knockout adult mice to modulate PKCε/Prox1 activity, similar effects were discovered in adult mice injected with lentivirus encoding Prox1, and more dramatic effects were found in PKCε knockout mice with concurrent Prox1 overexpression. In conclusion, morphine mediates lineage-specific NSPC differentiation, inhibits adult neurogenesis and regulates contextual memory retention via the PKCε/Prox1 pathway, which are implicated in the eventual context-associated relapse.

S-oxiracetam ameliorates ischemic stroke induced neuronal apoptosis through up-regulating α7 nAChR and PI3K / Akt / GSK3ß signal pathway in rats.

Ischemic stroke, the main reason for severe disabilities in the world, is associated with a high incidence of sensorimotor and cognitive dysfunction. In this study, we use the middle cerebral artery occlusion/reperfusion (MCAO/R) model in rats and oxygen glucose deprivation/reoxygenation (OGD/R) model in fetal rat primary cortical neurons to investigate whether and how S-oxiracetam (S-ORC) protect brain injury from ischemic stroke. The results revealed that S-ORC reduced brain infarct size and lessened neurological dysfunction after stroke. Further study demonstrated that S-ORC diminished TUNEL positive cells, increased cell viability, decreased LDH activity, and inhibited cell apoptotic rate. Furthermore, S-ORC inhibited neuronal apoptosis by activating the PI3K/Akt/GSK3ß signaling pathway via α7 nAChR, which was evidenced by α7 nAChR siRNA. In conclusion, our findings strongly suggest that S-ORC could be used as an effective neuroprotective agent for ischemic stroke due to its effect in preventing neuronal apoptosis.

Traditional Uses, Origins, Chemistry and Pharmacology of Bombyx batryticatus: A Review.

Bombyx batryticatus (B. batryticatus), a well-known traditional animal Chinese medicine, has been commonly used in China for thousands of years. The present paper reviewed advances in traditional uses, origin, chemical constituents, pharmacology and toxicity studies of B. batryticatus. The aim of the paper is to provide more comprehensive references for modern B. batryticatus study and application. In Traditional Chinese Medicine (TCM) culture, drugs containing B. batryticatus have been used to treat convulsions, headaches, skin prurigo, scrofula, tonsillitis and fever. Many studies indicate B. batryticatus contains various compounds, including protein and peptides, fatty acids, flavonoids, nucleosides, steroids, coumarin, polysaccharide and others. Numerous investigations also have shown that extracts and compounds from B. batryticatus exert a wide spectrum of pharmacological effects both in vivo and in vitro, including effects on the nervous system, anticoagulant effects, antitumor effects, antibacterial and antifungal effects, antioxidant effects, hypoglycemic effects, as well as other effects. However, further studies should be undertaken to investigate bioactive compounds (especially proteins and peptides), toxic constituents, using forms and the quality evaluation and control of B. batryticatus. Furthermore, it will be interesting to study the mechanism of biological activities and structure-function relationships of bioactive constituents in B. batryticatus.

S-oxiracetam protect against ischemic stroke via alleviating blood brain barrier dysfunction in rats.

The blood brain barrier (BBB) maintains the basic stability of the brain tissue under physiological conditions, while destroys and exaggerates brain edema and inflammatory response after ischemic stroke. In this study, we researched S-oxiracetam (S-ORC), a nootropic drug, alleviates BBB dysfunction and protects against ischemic stroke in rats. Middle cerebral artery occlusion(MCAO)/reperfusion in rats is applied to mimic ischemic stroke. One hour after reperfusion, rats are administered intravenously with different dose (0.12, 0.24, or 0.48g/kg) of S-ORC for continuative three days. Seventy-two hours after MCAO, TTC staining, hematoxylin and eosin (H&E) staining, brain water content, immunohistochemical staining, EB extravasation, western blot are provided to evaluate the protective effect and possible mechanism of S-ORC on BBB dysfunction. Furthermore, brain concentration of verapamil (P-glycoprotein substrate) and atenolol (paracellular transport marker) were assayed by UPLC-MS/MS co administration with or without S-ORC. The results show that post-treatment of S-ORC decreases cerebral infarct size, lessens brain edema, inhibits neutrophil infiltration and cytokines releasing. Furthermore, S-ORC treatment decreases EB leakage, downregulates MMP-9, upregulates occludin and claudin-5, and decreases brain concentration of verapamil and atenolol after MCAO surgery. In conclusion, the present study demonstrates that post-treatment of S-ORC alleviates BBB dysfunction by regulating tight junction proteins (TJPs), upregulating P-glycoprotein function, and protects against ischemic stroke as result.

The neuroprotective effect of a novel agent N2 on rat cerebral ischemia associated with the activation of PI3K/Akt signaling pathway.

Ischemic stroke is the third leading cause of death and the main reason for severe disabilities in the world today. N2, 4 - (2 - (1H - imidazol - 1 - yl) ethoxy) - 3 - methoxybenzoic acid is considered as a novel potent agent for cerebral ischemia due to its effect in preventing neuronal cell death after ischemic stroke. In the present study, we investigated the post-ischemic neuroprotective effect of N2 and its underlying mechanisms. Using a MCAO rat model, we found that N2 reversed brain infarct size, reduced cerebral edema and decreased the neurological deficit score significantly. Moreover, N2 diminished TUNEL positive cells, down-regulated bax expression and up-regulated bcl-2 expression notably. In addition, we evaluated the oxygen glucose deprivation/reoxygenation (OGD/R) injury induced neuron cell death in rat primary cortical neuron and assessed the neuroprotective effect of our drug. N2 increased cell viability, ameliorated neuron cell injury by decreasing LDH activity, and inhibited cell apoptotic rate while suppressed apoptotic signaling via inhibiting the bax expression, and elevating the bcl-2 expression. Furthermore, the neuroprotective effect of N2 was associated with the PI3K/Akt pathway which was proved by the use of PI3K inhibitor LY294002. The combination of our findings disclosed that N2 can be used as an effective neuroprotective agent for ischemic stroke due to its significant effect on preventing neuronal cell death after cerebral ischemia both in vivo and in vitro and the effectiveness was dose dependent.