• Proceedings of the PSK Conference
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• 2003.10b
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• pp.204.2-204.2
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• 2003

The aqueous extract of European mistletoe (Viscum album, L.) has been used in cancer therapy. The purified mistletoe lectins, main components of mistletoe, have demonstrated cytotoxic and immune-system-stimulating activities. Korean mistletoe (Viscum album L. coloratum), a subspecies of European mistletoe, has also been reported to possess anticancer and immunological activities. A galactose- and N-acetyl-D-galactosamine- specific lectin (Viscum album L. coloratum agglutinin, VCA) with Mr 60 kDa was isolated from Korean mistletoe. (omitted)

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.109.2-109.2
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• 2000

• Korean Journal of Pharmacognosy
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• v.35 no.2 s.137
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• pp.134-138
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• 2004

A bioassay-guided fractionation of the whole extract of Viscum album var. coloratum Ohwi (Loranthaceae) led to the isolation of two triterpenoidal components; oleanolic acid (1) and ${\beta}-amyrin$ acetate (2), and a flavonoid, homoflavoyadorinin B (3) as well as large quantity of free fatty acid mixtures as active ingredients of the extract responsible for the antitumoral property. The EtOAc soluble fraction and BuOH soluble fraction of the extract demonstrated a significant inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system), and HCT-15 (colon) in vitro, whereas the remaining water soluble fraction exhibited a poor inhibition. The intensive phytochemical investigation of the EtOAc soluble fraction and BuOH soluble fraction of the extract indicated that the oleanolic acid (1) and large amounts of free fatty acid mixtures might be attributed to the in vitro antitumoral property of the whole extract of Viscum album var. coloratum.

• Natural Product Sciences
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• v.21 no.2
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• pp.134-140
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• 2015

The present study aims to investigate the effect of methanol extract of Korean mistletoe (KM; Viscum album var. coloratum), on amyloid $\beta$ protein ($A\beta$) (25-35), a synthetic 25-35 amyloid peptide, -induced neurotoxicity in cultured rat cerebral cortical neurons and memory impairment in mice. Exposure of cultured neurons to $10{\mu}M$ $A\beta$ (25-35) for 24 h induced a neuronal cell death, which was measured by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. KM (10, 30 and $50{\mu}g/ml$) significantly inhibited the $A\beta$ (25-35)-induced apoptotic neuronal death. KM ($50{\mu}g/ml$) inhibited 10 μM Aβ (25-35)-induced elevation of intracellular calcium concentration ([Ca²⁺]_i), which was measured by a fluorescent dye, Fluo-4 AM. Glutamate release into medium and generation of reactive oxygen species (ROS) induced by $10{\mu}M$ $A\beta$ (25-35) were also inhibited by KM (10, 30 and $50{\mu}g/ml$). These results suggest that KM may mitigate the $A\beta$ (25-35)-induced neurotoxicity by interfering with the increase of [Ca²⁺]_i and then inhibiting glutamate release and generation of ROS in cultured neurons. In addition, orally administered KM (25 and 50 mg/kg, 7 days) significantly prevented memory impairment induced by intracerebroventricular injection of $A\beta$ (25-35) (8 nmol). Taken together, it is suggested that anti-dementia effect of KM is due to its neuroprotective effect against $A\beta$ (25-35)-induced neurotoxicity and that KM may have therapeutic role in prevention of the progression of Alzheimer's disease.

• BMB Reports
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• v.39 no.5
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• pp.560-570
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• 2006

Mistletoe (Viscum album) lectins, which are classified as a type II ribosome-inactivating protein (RIP) due to their unique biological function and the potential medical and therapeutic application in cancer cells, receive a rising attention. The heterodimeric glycoproteins contain the A-chain with catalytic activity and the B-chain with sugar binding properties. In recent years, studies involving the lectins from the white berry European mistletoe (Viscum album) and the yellow berry Korean mistletoe (Viscum album coloratum) have been described. However, the detailed mechanism in exerting unique cytotoxic effect on cancer cells still remains unclear. Here, we aim to understand and define the molecular basis and biological effects of the type II RIPs, through the studies of the recombinant Korean mistletoe lectin. To this end, we expressed, purified the recombinant Korean mistletoe lectin (rKML), and investigated its molecular characteristics in vitro, its cytotoxicity and ability to induce apoptotic cell death in cancer cells. To gain structural basis for its catalytic activity and sugar binding properties, we performed homology modeling studies based on the high degree of sequence identity and conserved secondary structure prediction between Korean and European, Himalayan mistletoe lectins, and Ricin.

• Korean Journal of Pharmacognosy
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• v.39 no.4
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• pp.310-315
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• 2008

Viscum album coloratum (Korean mistletoe; KM) is a semi-parasitic plant growing on various trees. This plant hasbeen shown to possess a variety of biological functions such as immunomodulation, apoptosis-induction and antitumor activity. However, there is no information about how the extract of KM affects life span of the host. In this study, in order to examine the effect of KM on the longevity of the host, we investigated whether a Korean mistletoe extract (KME) was able to extend the life length in an experimental model using the spring silkworm moth of Bombyx mori (Lepidoptera bombycidae). We established a model test for survival in which all of the male and female moths died within 18 days after the beginning of the experiment. Mean survival time of female moths was longer than that of male moths. Both male and female moths fed with KME containing diet (200 or 400 ${\mu}g$/head/day) showed significantly higher mean survival times than those of the control moths. Studying the effect of KME on prolongation of mean survival time showed that male moths were more susceptible than female moths. The moths fed with KME-containing diet showed a slight decrease in body weight. Interestingly, however, no difference in food intake was observed between moths fed with KME-containing diet and those with control diet. In analysis for mRNA increase in the SIRT2 gene, a member of the Sir2 gene family playing important roles in regulation of cell death and prolongation of life span, moths fed with KME-containing diet showed a significant increase in SIRT2 gene expression. These results suggest that KME has a potential to extend the life span in Bombyx mori, and its effect is partly associated with increase in SIRT2 gene expression.

• Journal of Life Science
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• v.32 no.5
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• pp.355-361
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• 2022

Melanin pigments are the main cause of skin color. They are produced in melanocytes and then transferred to keratinocytes, which eventually gives the skin surface a variety of colors. Although many skin-lightening or depigmenting agents have been developed, the demand for materials to reduce pig- mentation is still increasing. Here, we tried to find materials for skin-lightening or depigmentation using natural compounds and found that mistletoe (Viscum album var. coloratum) extracts (ME) had an inhibitory effect on tyrosinase activity. As a result, ME significantly reduced pigmentation in human primary melanocytes. In addition, a promoter reporter assay revealed that ME inhibited the transcription of microphthalmia-associated transcription factor (MITF), melanophilin (MLPH), tyrosinase-related protein-2 (TRP-2), and tyrosinase (TYR) genes in HM3KO melanoma cells. In addition, ME decreased the protein level for pigmentation-related molecules, such as TYR and TRP-1. Furthermore, it markedly inhibited the melanogenesis of zebrafish embryos, an in vivo evaluation model for pigmentation. To elucidate the action mechanism of ME, we investigated its effects on intracellular signaling. Eventually, the ME dramatically decreased the phosphorylation of the cAMP responsive element binding protein (CREB), AKT, and ERK. The data suggest that ME may inhibit the melanogenesis pathway by regulating the signaling pathway related to pigmentation. Taken together, these data propose that ME can be developed as a depigmenting or skin-lightening agent.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.253-253
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• 2005

• Archives of Pharmacal Research
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• v.20 no.4
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• pp.306-312
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• 1997

We attempted to isolate and characterize the lectins from stem and leaves of Korean mistletoe (Viscum album var. coloratum) by affinity chromatography. Lectin I was isolated only from stem. Lectin II was not isolated from Korean mistletoe, whereas lectin III was isolated from the stem and leaves. The hemagglutinating activity of lectin I was 16HU and inhibited by D-galactose, lactose, and N-acetyl-D-galactosamine. The lectin I has molecular weight of 60, 000D being composed of two basic subunits with molecular weights of 32, 000D and 28, 000D which are linked by a disufide bond. The lectin III from stem has molecular weight of 66, 000D being two basic subunits which have molecular weights of 34, 000D and 29, 000D and are linked by a disufide bond. The activity of lectin I was stable at the pH range of 4.00-8.50 and at a wide range of temperature (0-42.deg. C). The lectin I showed more potent mitogenic activity to murine lymphocytes than concanavalin A.

• Natural Product Sciences
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• v.9 no.4
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• pp.278-285
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• 2003

The serine proteases such as human leukocyte elastase (HLE) and porcine pancreatic elastase (PPE) are classified in the chymotrypsin family, and possibly the most destructive enzymes having the ability to degrade virtually all of the connective components in the body. In the present study, the extracts of water and methanol of Korean mistletoe (Viscum album var. coloratum) inhibited significantly the PPE activity. The fractions eluated on Amberlite XAD-2 from methanol extract were further purified on the repeated $SiO_2$ column chromatography and the fractions A, B and C were eluated. The fractions A, B and C at 3 mg/ml inhibited significantly the PPE activity up to 66%, 95% and 85%, respectively. In conclusion, the fraction A assumed as lignans or phenylpropanes, and fraction B and C assumed as triterpenoids showed the PPE inhibitory effects on the PPE and that these compounds in mistletoe may be used for treatment of pathological processes such as age-dependent tissue loss or inflammation.