Ewa Skała

IN VITRO REGENERATION OF SALVIA NEMOROSA L. FROM SHOOT TIPS AND LEAF EXPLANTS

SummaryShoot tips and leaves excised from in vitro shoot cultures of Salvia nemorosa were evaluated for their organogenic capacity under in vitro conditions. The best shoot proliferation from shoot tips was obtained on Murashige and Skoog (MS) medium supplemented with 8.9 μM 6-benzylaminopurine (BA) and 2.9 μM indole-3-acetic acid (IAA). Leaf lamina and petiole explants formed shoots through organogenesis via callus stage and/or directly from explant tissue. The highest values for shoot regeneration were obtained with 0.9 μM BA and 2.9 μM IAA for lamina explants. No shoot organogenesis was obtained on leaf explants cultured on MS medium supplemented with α-naphthaleneacetic acid (NAA). The regenerated shoots rooted the best on MS medium containing 0.6 μM IAA or 0.5 μM NAA. In vitro-propagated plants were transferred to soil with a survival rate of 85% after 3 mo.

Establishment of Hairy Root Cultures of Rhaponticum carthamoides (Willd.) Iljin for the Production of Biomass and Caffeic Acid Derivatives

The aim of the study was to obtain transformed roots of Rhaponticum carthamoides and evaluate their phytochemical profile. Hairy roots were induced from leaf explants by the transformation of Agrobacterium rhizogenes strains A4 and ATCC 15834. The best response (43%) was achieved by infection with A4 strain. The effects of different liquid media (WPM, B5, SH) with full and half-strength concentrations of macro- and micronutrients on biomass accumulation of the best grown hairy root line (RC3) at two different lighting conditions (light or dark) were investigated. The highest biomass (93 g L−1 of the fresh weight after 35 days) was obtained in WPM medium under periodic light. UPLC-PDA-ESI-MS3 and HPLC-PDA analyses of 80% aqueous methanol extracts from the obtained hairy roots revealed the presence of eleven caffeoylquinic acids and their derivatives and five flavonoid glycosides. The production of caffeoylquinic acids and their derivatives was elevated in hairy roots grown in the light. Only light-grown hairy roots demonstrated the capability for the biosynthesis of such flavonoid glycosides as quercetagetin, quercetin, luteolin, and patuletin hexosides. Chlorogenic acid, 3,5-di-O-caffeoylquinic acid and a tentatively identified tricaffeoylquinic acid derivative were detected as the major compounds present in the transformed roots.

A preliminary study of apoptosis induction in glioma cells via alteration of the Bax/Bcl-2-p53 axis by transformed and non-transformed root extracts of Leonurus sibiricus L.

Leonurus sibiricus L. is a traditional medicinal plant which occurs in southern Siberia, China, Korea, Japan, and Vietnam. The plant shows several pharmacological effects, but the most interesting is its anti-cancer activity. The aim of our study was to examine the induction of apoptosis in malignant glioma cells, the most aggressive primary brain tumors of the central nervous system, following treatment with transformed root (TR) or non-transformed root (NR) L. sibiricus extracts. Both the NR and TR extracts were found to have cytotoxic activity in the glioma primary cells. The human glioblastoma cell lines obtained from patients were confirmed to be tumorogenic by the following three markers: D10S1709, D10S1172, and D22S283. HPLC and MS analysis revealed the presence of polyphenolic compounds (chlorogenic acid, ferulic acid, caffeic acid, p-coumaric acid, ellagic acid, and verbascoside) in both sets of root extracts. In summary, our findings demonstrate that treatment of the glioma cells with NR and TR extracts resulted (a) in significant cell growth inhibition, (b) S- and G2/M-phase cell cycle arrest, and (c) apoptosis in a dose-dependent fashion by changing Bax/Bcl-2 ratio (about 4-fold increase) and p53 (5-fold increase) activation. These findings indicate that NR and TR extracts exhibit anti-cancer activity through the regulation of genes involved in apoptosis. This is the first report to demonstrate the cytotoxic effect of polyphenolic extracts from L. sibiricus roots against glioma cells, but further studies are required to understand the complete mechanism of its apoptosic activity.

The Effect of Leonurus sibiricus Plant Extracts on Stimulating Repair and Protective Activity against Oxidative DNA Damage in CHO Cells and Content of Phenolic Compounds

Leonurus sibiricus L. has been used as a traditional and medicinal herb for many years in Asia and Europe. This species is known to have antibacterial, anti-inflammatory, and antioxidant activity and has demonstrated a reduction of intracellular reactive oxygen species. All tested extracts of L. sibiricus showed protective and DNA repair stimulating effects in Chinese hamster ovary (CHO) cells exposed to H2O2. Preincubation of the CHO cells with 0.5 mg/mL of plant extracts showed increased expression level of antioxidant genes (SOD2, CAT, and GPx). LC-MS/MS and HPLC analyses revealed the presence of nine phenolic compounds in L. sibiricus plant extracts: catechin, verbascoside, two flavonoids (quercetin and rutin), and five phenolic acids (4-hydroxybenzoic acid, chlorogenic acid, caffeic acid, p-coumaric acid, and ferulic acid). The roots and aerial parts of in vitro L. sibiricus plant extracts, which had the strongest antioxidant properties, may be responsible for stimulating CHO cells to repair oxidatively induced DNA damage, as well as protecting DNA via enhanced activation of the antioxidant genes (SOD2, CAT, and GPx) regulating intracellular antioxidant capacity. The content of phenolic compounds in in vitro raised plants was greater than the levels found in plants propagated from seeds.

Antibacterial, Anti-Inflammatory, Antioxidant, and Antiproliferative Properties of Essential Oils from Hairy and Normal Roots of Leonurus sibiricus L. and Their Chemical Composition

Essential oils obtained from the NR (normal roots) and HR (hairy roots) of the medicinal plant Leonurus sibiricus root were used in this study. The essential oil compositions were detected by GC-MS. Eighty-five components were identified in total. Seventy components were identified for NR essential oil. The major constituents in NR essential oil were β-selinene (9.9%), selina-4,7-diene (9.7%), (E)-β-caryophyllene (7.3%),myli-4(15)-ene (6.4%), and guaia-1(10),11-diene (5.9%). Sixty-seven components were identified in HR essential oil, the main constituents being (E)-β-caryophyllene (22.6%), and germacrene D (19.8%). The essential oils were tested for cytotoxic effect, antimicrobial, anti-inflammatory, and antioxidant activities. Both essential oils showed activity against grade IV glioma cell lines (IC50 = 400 μg/mL), antimicrobial (MIC and MFC values of 2500 to 125 μg/mL), and anti-inflammatory (decreased level of IL-1β, IL-6, TNF-α, and IFN-γ in LPS-stimulated cells).The essential oils exhibited moderate antioxidant activity in ABTS (EC50 = 98 and 88 μg/mL) assay. This is the first study to examine composition of the essential oils and their antimicrobial, antioxidant, antiproliferative, and anti-inflammatory activities. The results indicate that essential oils form L. sibiricus root may be used in future as an alternative to synthetic antimicrobial agents with potential application in the food and pharmaceutical industries.

Inhibition of human glioma cell proliferation by altered Bax/Bcl-2-p53 expression and apoptosis induction by Rhaponticum carthamoides extracts from transformed and normal roots

The objective of this study was to determine the cytotoxic effect and apoptotic activity of Rhaponticum carthamoides transformed root (TR) and root of soil‐grown plant (NR) extracts in a human glioma primary cells. The effect of these root extracts on cell cycle arrest, mitochondrial membrane potential (ΔΨm) and expression levels of apoptosis‐related genes (Bcl‐2, Bax and p53) were also examined.

Tanshinone production in roots of micropropagated Salvia przewalskii Maxim.

Production of tanshinones (tanshinone I and IIA) was determined in roots of Salvia przewalskii micropropagated plants. It was found that the total tanshinone content (tashinone I and tashinone IIA) was dependent on the age of the analyzed plants. The roots of 2-year-old in vitro regenerated plants at flowering stage produced highest tanshinone levels (3.8 mg/g dry weight of tanshinone I and 7.6 mg/g dry weight of tanshinone IIA).

In vitro propagation and chemical and biological studies of the essential oil of Salvia przewalskii Maxim.

The procedure of Salvia przewalskii shoot multiplication and the ability of regenerated plants to produce essential oil is reported. The essential oil was obtained by hydrodistillation from leaves and flowering stems of field-grown plants, and their chemical composition was examined by GC, GC-MS and 1H NMR. The differences in yield as well as qualitative and quantitative composition between the oils isolated from in vitro and in vivo plants were observed. S. przewalskii essential oil was tested for its antimicrobial and cytotoxic properties. It was found that cytotoxicity against human leukemia HL-60 cells and antimicrobial activity (especially, against Staphylococcus aureus and S. epidermidis strains) of oils isolated from in vitro plants were higher than those for oils from in vivo S. przewalskii plants.

Antioxidant and DNA Repair Stimulating Effect of Extracts from Transformed and Normal Roots of Rhaponticum carthamoides against Induced Oxidative Stress and DNA Damage in CHO Cells

Rhaponticum carthamoides has a long tradition of use in Siberian folk medicine. The roots and rhizomes of this species are used in various dietary supplements or nutraceutical preparations to increase energy level or eliminate physical weakness. This is the first report to reveal the protective and DNA repair stimulating abilities of R. carthamoides root extracts in Chinese hamster ovary (CHO) cells exposed to an oxidative agent. Both transformed root extract (TR extract) and extract of soil-grown plant roots (NR extract) may be responsible for stimulating CHO cells to repair oxidatively induced DNA damage, but CHO cells stimulated with extract from the transformed roots demonstrated significantly stronger properties than cells treated with the soil-grown plant root extract. These differences in biological activity may be attributed to the differences in the content of phenolic compounds in these root extracts. Preincubation of the CHO cells with TR and NR extracts showed an increase in gene expression and protein levels of catalase (CAT) and superoxide dismutase (SOD2). R. carthamoides may possess antioxidant properties that protect CHO cells against oxidative stress.

Over-Expression of AtPAP1 Transcriptional Factor Enhances Phenolic Acid Production in Transgenic Roots of Leonurus sibiricus L. and Their Biological Activities

This study examines the production of five phenolic acids (chlorogenic acid, neochlorogenic acid, ferulic acid, caffeic acid and p-coumaric acid) following over-expression of AtPAP1 transcription factor by four transgenic root clones of Leonurus sibiricus after Agrobacterium rhizogenes transformation. The AtPAP1 expression level was estimated by quantitative real-time PCR. High levels of phenolic acids were found in the transgenic roots of L. sibiricus and were determined by high-performance liquid chromatography–mass spectrometry analysis. Additionally, transgenic roots showed antimicrobial potential and cytotoxic activity on glioma cells in IV grade. Our results suggest that L. sibiricus transformed roots with AtPAP1 gene over-expression may represent a potential source of phenolic acids.