Continentalic acid from Aralia continentalis induces growth inhibition and apoptosis in HepG2 cells

A Comprehensive Review of Traditional Medicinal Uses, Geographical Distribution, Botanical Characterization, Phytochemistry, and Pharmacology of Aralia continentalis Kitag

Aralia continentalis Kitag. (A. continentalis) holds significant medicinal value among the Aralia genus. It has traditionally been employed in ethnomedicine to address a wide range of conditions, including wind-cold-dampness arthralgia; rheumatic pain in the waist and lower extremities; lumbar muscular strain; injuries resulting from falls, fractures, contusions, and strains; headache; toothache; and abscesses. Modern pharmacological research has validated its therapeutic potential, encompassing anti-inflammatory, analgesic, antioxidant, antimicrobial, insecticidal, hepatoprotective, anti-diabetic, and cytotoxic properties, among other pharmacological effects. To compile comprehensive knowledge on A. continentalis, a rigorous literature search was undertaken utilizing databases like SciFinder, PubMed, and Web of Science. This review seeks to delve into the plant's traditional applications, geographical distribution, botanical characteristics, phytochemistry, and pharmacology. The objective is to lay a foundation and propose novel research directions for exploring the plant's potential applications. Currently, one hundred and fifty-nine compounds have been isolated and identified from A. continentalis, encompassing diterpenoids, steroids, triterpenoids, volatile components, phenolics, vitamins, trace elements, and other compounds. Notably, diterpenoids, steroids, triterpenoids, volatile components, and phenolics have exhibited pronounced pharmacological effects, such as anti-inflammatory, analgesic, antioxidant, hepatoprotective, antidiabetic, and antimicrobial activities. However, despite the extensive research conducted, further studies are imperative to unravel new components and mechanisms of action, necessitating more in-depth investigations. This comprehensive exploration could pave the way for advancing and harnessing the potential of A. continentalis.

Traditional uses, phytochemistry, pharmacology, toxicity and quality control of medicinal genus Aralia: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Aralia, which belongs to Araliaceae family, is mainly distributed in Asia, such as China, Japan and South Korea. It has a long medicinal history and is widely used in the treatment of various diseases, such as hepatitis, rheumatoid arthritis, bruises, lumps and carbuncles.

AIM OF THE STUDY

The purpose of this review is to systematically evaluate the traditional uses, phytochemistry, pharmacology, toxicity and quality control of main medicinal plants of Aralia, discusses the application of ethnic medicine, modern scientific research and the relationship between them, and put forward some suggestions to promote the further development and utilization of Aralia.

MATERIALS AND METHODS

The relevant information on Aralia was collected through electronic databases (PubMed, Web of Science, Science Direct, Springer, CNKI and Wanfang), Chinese herbal classics, Ph.D. and M.Sc. dissertations, Chinese Pharmacopoeia. Plant names were verified by "The Plant List" (http://www.theplantlist.org). The literature cited in this review can be traced back to 1878 to 2021.

RESULTS

More than 290 chemical constituents have been isolated from the genus Aralia, including triterpenoid saponins, terpenoids, organic acids, flavonoids, polyacetylenes, phenylpropanoids and other constituents. Pharmacological studies have shown that the extracts and compounds of Aralia have a wide range of pharmacological activities, including anti-inflammation, analgesic, anti-tumor, liver protection, protection of cardiovascular and nervous system, regulating substance metabolism, antibacterial, antiviral and antioxidation.

CONCLUSIONS

The genus Aralia is not only an excellent traditional herbal medicine, but also a source of bioactive molecules with good application prospects. However, the structure-activity relationship, in vivo activity and action mechanism of its bioactive components need to be further studied. In addition, more toxicological and quality control studies are essential to evaluate the efficacy and safety of Aralia as medicine.

Anticancer Activity of Continentalic Acid in B-Cell Lymphoma

Aralia continentalis has been used in Korea as a folk remedy for arthralgia, rheumatism, and inflammation. However, its anti-lymphoma effect remains uncharacterized. Here, we demonstrate that A. continentalis extract and its three diterpenes efficiently kill B-lymphoma cells. Our in vitro and in vivo results suggest that the cytotoxic activities of continentalic acid, a major diterpene from A. continentalis extract, are specific towards cancer cells while leaving normal murine cells and tissues unharmed. Mechanistically, continentalic acid represses the expression of pro-survival Bcl-2 family members, such as Mcl-1 and Bcl-xL. It dissociates the mitochondrial membrane potential, leading to the stimulation of effector caspase 3/7 activities and, ultimately, cell death. Intriguingly, this agent therapeutically synergizes with roflumilast, a pan-PDE4 inhibitor that has been successfully repurposed for the treatment of aggressive B-cell malignancies in recent clinical tests. Our findings unveiled that A. continentalis extract and three of the plant’s diterpenes exhibit anti-cancer activities. We also demonstrate the synergistic inhibitory effect of continentalic acid on the survival of B-lymphoma cells when combined with roflumilast. Taken in conjunction, continentalic acid may hold significant potential for the treatment of B-cell lymphoma.

Optimization of Extraction Conditions of Continentalic and Kaurenoic Acids from Aralia continentalis by HPLC/UV and Their Validation

Aralia continentalis (AC) is a perennial herb that has long been used as a traditional medicine for many diseases. Continentalic acid (CA) and kaurenoic acid (KA) are major diterpenoids in AC, which are known to exert various pharmacological activities. This study focuses on the optimization of the extraction of CA and KA from dried AC roots by evaluating the influence of different extraction conditions on their yield. Five extraction variables were examined: sample weight, solvent concentration, extraction time, solid matrix and the number of repeated extractions. The analytical method used in this study was also validated in terms of linearity, limit of detection, limit of quantification, precision and accuracy. The CA and KA yields were measured by high-performance liquid chromatography analysis. The results show that CA and KA were the highest when unpulverized samples (3.75 g) were subjected to a single extraction for 5 h using 50% ethanol (300 mL) as the solvent. These conditions are proposed for the optimization of the extraction of CA and KA from AC.

A Transannular Polyene Tetracyclization for Rapid Construction of the Pimarane Framework

Polyene cyclizations are one of the most powerful and fascinating chemical transformations to rapidly generate molecular complexity. However, cyclizations employing heteroatom-substituted polyenes are rare. Described here is the tetracyclization of a dual nucleophilic aryl enol ether involving an unprecedented transannular endo-termination step. In this transformation, five stereocenters, two of which are quaternary, four carbon-carbon bonds, and four six-membered rings are formed from a readily available cyclization precursor. The realization of this cyclization enabled short synthetic access to the tricyclic diterpenoid pimara-15-en-3α-8α-diol.

Continentalic Acid Rather Than Kaurenoic Acid Is Responsible for the Anti-Arthritic Activity of Manchurian Spikenard In Vitro and In Vivo

The aim of this study was to identify the active compound responsible for the pharmacological activities of Manchurian spikenard (Aralia continentalis Kitag.). Interleukin (IL)-1β-stimulated human chondrocytes and monoiodoacetate (MIA)-induced osteoarthritic rats were treated with the 50% ethanolic extract of spikenard or its major components, such as continentalic acid (ent-pimara-8(14),15-diene-19-oic acid) and kaurenoic acid (ent-kaura-16-en-19-oic acid). The spikenard extract significantly inhibited IL-1β-stimulated production of IL-6, IL-8, metalloproteinase (MMP)-1, MMP-13, cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and prostaglandin(PG)E2 in a dose-dependent manner but not MMP-3 production. The extract also inhibited the IL-1β-induced translocation of NF-κB/p65 into the nucleus and dose-dependent phosphorylation levels of extracellular signal-regulated kinase (ERK), Jun amino-terminal kinase (JNK) and p38 mitogen-activated protein (MAP) kinase. Continentalic acid exhibited significant anti-arthritic activity corresponding exactly to that of the extract containing an equivalent amount of continentalic acid. On the other hand, kaurenoic acid exhibited a compatible activity at about a 10-times higher molar concentration than that of continentalic acid. In vitro anti-arthritic activities of the spikenard extract and continentalic acid were also confirmed in MIA-induced osteoarthritic rats. The 50% ethanolic extract of Manchurian spikenard exhibited promising anti-arthritic activities in the in vitro and in vivo osteoarthritis models, and continentalic acid, not kaurenoic acid, was most probably responsible for those activities.

Quality control of a herbal medicinal preparation using high-performance liquid chromatographic and capillary electrophoretic methods

Two methods based on high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE) were developed for the quality control of "samgiumgagambang" (SGMX), a new herbal medicinal preparation containing 14 herbs. Nine components from SGMX were selected as markers: 5-hydroxymethylfuraldehyde, geniposidic acid, chlorogenic acid, paeoniflorin, 20-hydroxyecdysone, coptisine, berberine, luteolin, and glycyrrhizic acid. The markers were identified and analyzed using HPLC coupled with a UV-diode-array detector and monitored at 250nm with a gradient elution of acetonitrile and water containing formic acid on a C(18) analytical column or using CE with a 70mM borate buffer (pH 9.5) containing 10% methanol on a 60-cm fused silica capillary monitored at 230nm. The marker components in SGMX were well separated using both methods and were readily determined within 60min using HPLC or 13min using CE with good precision and accuracy.