Apoptosis of BGC823 cell line induced byp-hydroxymethoxybenzobijuglone, a novel compound fromJuglans mandshurica

Juglans mandshurica Maximowicz as a traditional medicine: review of its phytochemistry and pharmacological activity in East Asia

OBJECTIVES

The conducted search reveals that Juglans mandshurica Maximowicz, called Manchuria walnuts, had many local uses that can be categorized into cancer, dermatosis and acesodyne.

KEY FINDINGS

Various metabolites including diarylheptanoids, naphthoquinones, and flavonoids (also their glycosides) were reported as bioactive metabolites. The isolated metabolites and extracts from J. mandshurica showed different biological activity including cytotoxicity, anti-inflammation, antimelanotic, anticomplement, anti-HIV, antimicrobial and anti-obesity activity.

SUMMARY

It is indicated that this review will add value to more scientific research on J. mandshurica and enhance the increased interest in the sustainable commercialization of J. mandshurica. It also leads to the validation of unverified ethnobotanical claims. Future studies on J. mandshurica would be focused to establish the links between the pharmacological activity, bioactive metabolites, and traditional uses.

Juglans mandshurica Maxim.: A Review of Its Traditional Usages, Phytochemical Constituents, and Pharmacological Properties

Juglans mandshurica Maxim., also known as “Manchurian walnut” (Chinese) and “Onigurumi” (Japanese), is a medicinal plant widely distributed in Western and Central Asia, especially in China. It has been traditionally used to treat cancer, gastric ulcers, diarrhea, dysentery, dermatosis, uterine prolapse, and leukopenia. To date, more than 400 constituents including quinones (e.g. naphthoquinones, anthraquinones, naphthalenones, tetralones), phenolics, flavonoids, triterpenoids, coumarins, lignans, phenylpropanoids, diarylheptanoids, and steroids, were isolated and structurally identified from different plant parts of J. mandshurica. Among them, quinones, phenolics, triterpenoids, and diarylheptanoids, as the major bioactive substances, have been extensively studied and displayed significant bioactivity. Previous studies have demonstrated that J. mandshurica and a few of its active components exhibit a wide range of pharmacologically important properties, such as antitumor, immunomodulatory, anti-inflammatory, neuroprotective, anti-diabetic, antiviral, antimicrobial, and anti-melanogenesis activities. However, many investigations on biological activities were mainly based on crude extracts of this plant, and the major bioactive ingredients responsible for these bioactivities have not been well identified. Further in vitro and in vivo studies on the mechanisms of action of the pure bioactive compounds, and more elaborate toxicity studies as well as clinical studies are needed to ensure safety and effectiveness of the plant for human use. Taken together, the present review will provide some specific useful suggestions guide to further investigations and applications of this plant in the preparation of medicines and functional foods.

Two new quinones and six additional metabolites with potential anti-inflammatory activities from the roots of Juglans mandshurica

Two new quinones, 4-(5-hydroxy-1,4-dioxo-1,4-dihydronaphtha-len-3-ylamino)-butyric acid methyl ester (compound 1) and 1,3-dimethoxycarbonyl-8-hydroxy-9,10-anthraquinone (2), and six known compounds (3-8) were isolated from the roots of Juglans mandshurica Maxim., a member of the Juglandaceae family. The chemical structures of the compounds were elucidated by nuclear magnetic resonance spectroscopy and compared with data from the literature. The isolated compounds were evaluated for their ability to inhibit the production of nitric oxide, tumour necrosis factor-α, and interleukin-6 by the mouse macrophage RAW 264.7 cell line after lipopolysaccharide stimulation in vitro. We found that compounds 1-4 exhibited potent anti-inflammatory effects, as indicated by suppression of lipopolysaccharide-stimulated nitric oxide and cytokine production with 50% inhibitory concentrations between 20.09 μM and 27.63 μM. These results identify two novel quinones from J. mandshurica with potential utility as anti-inflammatory compounds.

Phytochemistry, Bioactivity and Potential Impact on Health of Juglans: the Original Plant of Walnut

Walnuts are seeds with a hard shell from the genus Juglans (J. mandshurica, J. regia, J. sinensis, J. cathayensis, J. nigra and J. sigillata). Walnuts can nourish brain cells to improve human memory. Other parts of the plant are also employed as traditional Chinese medicines. Modern research on Juglans species has been mostly focused on the above-mentioned species, the seeds of which are all called walnuts. Juglans species have diverse chemical constituents, including diarylheptanoids, quinones, polyphenols, flavones and terpenes. The diarylheptanoids and quinones have notable antitumor activity, supplying new lead compounds for preparing antitumor drugs. The potent pain-relieving, antioxidant, antibacterial and antitumor activities of these plants are significant. In the review, comprehensive information on the nutritional characteristics, traditional functions, chemical constituents, and biological activities of the Juglans species, together with the seeds used as walnuts is provided to explore their potential and to advance research.

Juglanthraquinone C Induces Intracellular ROS Increase and Apoptosis by Activating the Akt/Foxo Signal Pathway in HCC Cells

Juglanthraquinone C (JC), a naturally occurring anthraquinone extracted from Juglans mandshurica, could induce apoptosis of cancer cells. This study aims to investigate the detailed cytotoxicity mechanism of JC in HepG2 and BEL-7402 cells. The Affymetrix HG-U133 Plus 2.0 arrays were first used to analyze the mRNA expression exposed to JC or DMSO in HepG2 cells. Consistent with the previous results, the data indicated that JC could induce apoptosis and hyperactivated Akt. The Western blot analysis further revealed that Akt, a well-known survival protein, was strongly activated in HepG2 and BEL-7402 cells. Furthermore, an obvious inhibitory effect on JC-induced apoptosis was observed when the Akt levels were decreased, while the overexpression of constitutively active mutant Akt greatly accelerated JC-induced apoptosis. The subsequent results suggested that JC treatment suppressed nuclear localization and increased phosphorylated levels of Foxo3a, and the overexpression of Foxo3a abrogated JC-induced apoptosis. Most importantly, the inactivation of Foxo3a induced by JC further led to an increase of intracellular ROS levels by suppressing ROS scavenging enzymes, and the antioxidant N-acetyl-L-cysteine and catalase successfully decreased JC-induced apoptosis. Collectively, this study demonstrated that JC induced the apoptosis of hepatocellular carcinoma (HCC) cells by activating Akt/Foxo signaling pathway and increasing intracellular ROS levels.