Viscum album subsp. Coloratum, also known as Korean mistletoe, is a traditional herb that has more recently been used for the treatment of nervine, hypertensive and cardiovascular diseases. Therefore, this study was undertaken to access the anti-obesity effect of Korean mistletoe-derived polypeptide viscothionin using 3T3-L1 adipocytes in vitro and in vivo mouse experimental model. Viscothionin (up to 5 μM) was used to treat mouse 3T3-L1 pre-adipocytes during adipocyte differentiation. Adipocyte differentiation in 3T3-L1 cells was confirmed by Oil Red O staining. Obesity was induced by a high-fat diet (HFD) in C57BL/6J mice, followed by oral administration of viscothionin (up to 10 mg/kg) for 3 weeks. As a result, viscothionin (5 μM) inhibited differentiation of adipocyte cells and attenuated accumulation of intracellular lipids through activation of 5′-adenosine monophosphate-activated protein kinase (AMPK), by down-regulating phosphorylation in AKT and glycogen synthase kinase 3β (GSK3β). Treatment of viscothionin also decreased the levels of sterol regulatory element binding protein-1 (SREBP-1) and its target gene, fatty acid synthase (FAS). Moreover, viscothionin (10 mg/kg) significantly suppressed body weight and fat content, and improved serum lipid concentration, compared with the standard drug simvastatin (10 mg/kg), a well-known anti-obesity agent. The present study suggests, that viscothionin exerts anti-adipogenic effect through the activation of AMPK and has potential to prevent HFD-induced obesity.

This study was conducted to assess the repellent activity of Pogostemon cablin (Blanco) Benth. [Lamiaceae] essential oil (EO) and its nanoemulsion (NE) against Haemaphysalis longicornis nymphs. Pogostemon cablin EO nanoemulsion (PCNE) was prepared by ultrasonic emulsification using P. cablin EO and a surfactant, Tween 80. The results of gas chromatography–mass spectrometry analysis showed that the major component of P. cablin EO was patchouli alcohol (32.04%), followed by δ-guaiene (18.13%), α-guaiene (16.76%), seychellene (7.49%), and β-patchoulene (5.09%). The droplet sizes of PCNEs formulated using P. cablin EO and Tween 80 in ratios of 1:1, 1:2, and 1:3 were 23.8, 20.1 and 17.7 nm, respectively, indicating that the increase in the ratio of Tween 80 led to a decrease in droplet size. All essential oil preparations had an acceptable polydispersity index of 0.5 or less. The P. cablin EO and Tween 80 ratio of 1:3 was selected as the optimal formulation with the smallest droplet size; transmission electron microscopy indicated the formation of uniform spherical droplets. PCNE (84.0%) showed a higher repellent activity against H. longicornis nymphs than P. cablin EO (72.0%). The nanoemulsion is suitable for improving the repellent activity of P. cablin EO and is a potential repellent for H. longicornis.

Ji-yeong Ku, Jun-Hwan Park, Seo-Ho Kim, Yong-il Cho, Chan-Lan Kim, Seung-Eon Cha, Gee-Wook Shin, Jinho Park. Korean J. Vet. Serv. 2022;45:47-54. https://doi.org/10.7853/kjvs.2022.45.1.47