Effect of Berberine Isolated from Barberry Species by Centrifugal Partition Chromatography on Memory and the Expression of Parvalbumin in the Mouse Hippocampus Proper.

Neurodegenerative diseases associated with memory disturbances are important health issues occurring due to a prolonged life span. This article presents the results of a study targeting the emergence of a drug candidate with antiamnesic properties. The effect of berberine (BBR), an isoquinoline alkaloid isolated from the overground parts of Berberis sibirica Pall., on memory and expression of parvalbumin in the mouse hippocampus proper were determined. High-purity BBR was isolated by centrifugal partition chromatography from a methanolic extract from B. sibirica by using a methyl-tert-butyl ether and water (1:1 v/v) solvent system with 10 mmol/L of triethylamine and hydrochloric acid. In an in vivo study, we assessed the influence of the chronic administration of BBR on different stages of memory-related responses in mice. Our results indicated that the chronic administration of BBR in a higher dose (5 mg/kg) improves long-term memory acquisition in mice, as determined in the passive avoidance test. The hippocampal CA1-CA3 fields showed an increased number of parvalbumin-immunoreactive neurons (PV-IR) and nerve fibers as compared to the control. No significant changes in the dentate gyrus were observed between the groups. The HPLC-ESI-QTOF-MS/MS analysis of the biological material revealed the content of BBR as 363.4 ± 15.0 ng (4.11% of RSD) per brain, 15.06 ± 0.89 ng (5.91% of RSD) per hippocampus, and 54.45 ± 1.40 (4.05% of RSD) ng in 100 µL plasma. The study showed that BBR could be a factor influencing the expression of PV in hippocampal neurons. We speculate that BBR may modulate the level of Ca2+ in neurons and thus potentially act as a neuroprotective factor against neuronal damages.

6-Gingerol, a Major Constituent of Zingiber officinale Rhizoma, Exerts Anticonvulsant Activity in the Pentylenetetrazole-Induced Seizure Model in Larval Zebrafish.

Zingiber officinale is one of the most frequently used medicinal herbs in Asia. Using rodent seizure models, it was previously shown that Zingiber officinale hydroethanolic extract exerts antiseizure activity, but the active constituents responsible for this effect have not been determined. In this paper, we demonstrated that Zingiber officinale methanolic extract exerts anticonvulsant activity in the pentylenetetrazole (PTZ)-induced hyperlocomotion assay in larval zebrafish. Next, we isolated 6-gingerol (6-GIN)-a major constituent of Zingiber officinale rhizoma. We observed that 6-GIN exerted potent dose-dependent anticonvulsant activity in the PTZ-induced hyperlocomotion seizure assay in zebrafish, which was confirmed electroencephalographically. To obtain further insight into the molecular mechanisms of 6-GIN antiseizure activity, we assessed the concentration of two neurotransmitters in zebrafish, i.e., inhibitory γ-aminobutyric acid (GABA) and excitatory glutamic acid (GLU), and their ratio after exposure to acute PTZ dose. Here, 6-GIN decreased GLU level and reduced the GLU/GABA ratio in PTZ-treated fish compared with only PTZ-bathed fish. This activity was associated with the decrease in grin2b, but not gabra1a, grin1a, gria1a, gria2a, and gria3b expression in PTZ-treated fish. Molecular docking to the human NR2B-containing N-methyl-D-aspartate (NMDA) receptor suggests that 6-GIN might act as an inhibitor and interact with the amino terminal domain, the glutamate-binding site, as well as within the ion channel of the NR2B-containing NMDA receptor. In summary, our study reveals, for the first time, the anticonvulsant activity of 6-GIN. We suggest that this effect might at least be partially mediated by restoring the balance between GABA and GLU in the epileptic brain; however, more studies are needed to prove our hypothesis.

Acetylcholinesterase Inhibitors among Zingiber officinale Terpenes-Extraction Conditions and Thin Layer Chromatography-Based Bioautography Studies.

Although numerous studies have been conducted on ginger extracts and fractions, the data on the pharmacological activity of single constituents of Zingiber officinale are still insufficient. To assess the antidementia properties of the plant, a thin layer chromatography (TLC)-based bioautography acetylcholinesterase inhibitory assay was performed on the Zingiber officinale diethyl ether extract. It led to the recognition of three active inhibitors among volatile constituents of the plant: ar-curcumene (A), α-sesquiphellandrene (B) and a-zingiberene (C). The identification of the components was possible thanks to the application of a TLC-HPLC-MS interface analysis of active zones and the GC-MS qualitative analysis of the tested samples. Based on the obtained results, the influence of several extraction techniques (hydrodistillation-HD, pressurized liquid extraction or accelerated solvent extraction-ASE, shaking maceration-SM, supercritical fluid extraction-SFE, and ultrasound-assisted extraction-UAE) on the recovery of the active metabolites from plant material was assessed to deliver enriched extracts. As a result, HD and SFE, were found to be the most efficient methods to recover the volatile components and the concentrations of A, B, and C reached 0.51 ± 0.025, 0.77 ± 0.045, and 1.67 ± 0.11 percent, respectively. Only HD and SFE were found to recover monoterpene hydrocarbons from the plant matrix. The remaining techniques provided extracts rich in more complex constituents, like sesquiterpenes.

Antimicrobial Potential of Single Metabolites of Curcuma longa Assessed in the Total Extract by Thin-Layer Chromatography-Based Bioautography and Image Analysis.

Curcuma longa from Zingiberaceae belongs to the major spices consumed around the world, known from its cholagogue, anti-inflammatory, and antimicrobial properties. Lack of data on the activity of single components of turmeric extract encouraged the authors to apply TLC (thin-layer chromatography) based bioautography studies to reveal its antimicrobial constituents and construct a universal platform for the bioactivity assessment of crude extracts, with help of a freeware ImageJ software. This optimized chromatographic bioassay performed on diethyl ether and methanol extracts of Curcuma longa was successfully applied on the total extract and revealed the antimicrobial potential of single components against a variety of Gram-positive strains, with no need for their isolation from the mixture. The obtained results were further confronted with a classic microdilution antimicrobial assay on the isolates, purified from the crude extracts by centrifugal partition chromatography in the following solvent system: heptane-chloroform-methanol-water (5:6:3:2) (v/v/v/v).

Superior anticancer activity is demonstrated by total extract of Curcuma longa L. as opposed to individual curcuminoids separated by centrifugal partition chromatography.

Three curcuminoids: bisdemethoxycurcumin, demethoxycurcumin, and curcumin from turmeric were successfully separated by a high capacity solvent system composed of heptane: chloroform: methanol: water mixture (5: 6: 3: 2 v/v/v/v) tailored for centrifugal partition chromatographs at K-values of 0.504, 1.057, 1.644, respectively. These three ferulic acid derivatives obtained at a purity rate exceeding 95% were analysed by an HPLC-MS spectrometer. Turmeric extract inhibited the proliferation/viability of A549 human lung cancer, HT29 colon cancer, and T98G glioblastoma cell lines in (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) tetrazolium reduction assay (MTT). Single curcuminoids significantly decreased the viability/proliferation of lung cancer cells in a dose-dependent manner. However, total extract displayed the superior anticancer activity in the investigated cell lines. Crude extract in combination with cisplatin augmented the decrease in the viability of cancer cells compared with single compound treatment in A549 lung cancer cells. Total extract of Curcuma longa could be regarded as being more effective against lung cancer cells in vitro than its separated compounds.

MAO-A Inhibitory Potential of Terpene Constituents from Ginger Rhizomes-A Bioactivity Guided Fractionation.

BACKGROUND: In the search for novel antidepressive drug candidates, bioguided fractionation of nonpolar constituents present in the oleoresin from ginger rhizomes (Zingiber officinale Roscoe, Zingiberaceae) was performed. This particular direction of the research was chosen due to the existing reports on the antidepressive properties of ginger total extract. The search for individual metabolites acting as MAO-A inhibitors, which correspond to the apparent effect of the total extract, is the subject of this work. METHODS: Hexane extracts from ginger rhizomes were fractionated by using column chromatography (including silica gel impregnated with silver nitrate) and semi-preparative high-performance chromatography. For the activity assessment, an in vitro monoamine oxidase A (MAO-A) inhibition luminescence assay was performed on 10 purified terpenes: 1,8-cineole, α-citronellal, geraniol, ß-sesquiphellandrene, γ-terpinen, geranyl acetate, isobornyl acetate, terpinen-4-ol, (E,E)-α-farnesene, and α-zingiberene. RESULTS: Geraniol and (-)-terpinen-4-ol were found to be the strongest enzyme inhibitors with inhibition of 44.1% and 42.5%, respectively, at a concentration of 125 µg/mL. No differences in the inhibition potential were observed for the different groups of terpenes: sesquiterpenes, monoterpenes, or sesquiterpene alcohols; however, the two most active compounds contained a hydroxyl moiety. CONCLUSIONS: Terpene constituents from ginger's extract were found to exhibit moderate inhibitory properties against the MAO-A enzyme in in vitro tests.