Anti-toxoplasmosis effect of Dictamnus dasycarpus extract against Toxoplasma Gondii / 동물의과학연구지

Toxoplasma gondii (T. gondii) causes a life-threatening opportunistic infection. Despite its clinical importance, very few therapeutic drugs against T. gondii are available. Furthermore, these therapeutic regimens are not always suitable for prolonged treatment due to adverse side effects as well as the potential of clinical failure by selecting drug-resistant parasite variants. Dictamnus dasycarpus is known to have many medicinal properties, including anti-inflammatory, anti-fever, and anti-rheumatic activities. In this study, 70% ethanol extract of Dictamnus dasycarpus showed anti-T. gondii effects. Ethanolic extracts of Dictamnus dasycarpus used to treat T. gondii were tested in vitro for their anti-T. gondii activity and cytotoxicity. The selectivity of Dictamnus dasycarpus extract was 7.52, which was higher than that of Sulfadiazine (2.08). We conducted an in vivo animal test to evaluate the anti-T. gondii activity of Dictamnus dasycarpus extract as compared with that of Sulfadiazine. In T. gondii-infected mice, the inhibition rate of Dictamnus dasycarpus extract was high, similar to that of Sulfadiazine. This indicates that Dictamnus dasycarpus extract may be a source of new anti-T. gondii compounds.

Protective effect of halophyte Salsola komarovi Iljin against gastric ulcer Induced by alcohol treatment in rats / 동물의과학연구지

Salsola komarovi Iljin is a halophyte and herbaceous annual native to the sand dunes and beaches of Japan, northern China, Sakhalin, and Korea. The plants have been known as an ecologically important species for enhancing formation of sand dunes in Korea. The purpose of this study was to examine the anti-gastric ulcer effect of Salsola komarovi Iljin halophyte in an HCl-ethanol-induced gastritis model. SD rats (7-weeks-old) were divided into normal (I, n=10), control (II, 60% HCl-ethanol + water, n=10), 60% HCl-ethanol + Ranitidine 300 mg/kg (III, n=10), 60% HCl-ethanol + Salicornia herbacea L. 500 mg/kg (IV, n=10), 60% HCl-ethanol + 50% alcohol extract of Salsola komarovi Iljin 500 mg/kg (V, n=10), and 60% HCl-ethanol + water extract of Salsola komarovi Iljin 500 mg/kg (VI, n=10) groups. Salsola komarovi Iljin significantly suppressed gastric lesions and ulcers in the 60% HClethanol-induced gastric model. Especially, 500 mg/kg of 50% alcohol extract of Salsola komarovi Iljin showed significant inhibitory effects against gastritis. Especially, 50% alcohol extract of Salsola komarovi Iljin 500 mg/kg showed a significantly inhibitory effect, which was more potent than that of 300 mg/kg of Ranitidine. In histopathological analysis of the animal model, Salsola komarovi Iljin attenuated gastric ulcer formation. Our results suggest that Salsola komarovi Iljin has inhibitory effects against gastritis and gastric ulcers and could be developed as a new anti-gastric ulcer agent.

Effects of cold stress as a pathogenic factor on fatal disease progression of canine herpesvirus / 동물의과학연구지

Canine herpesvirus (CHV) is a member of the alphaherpesvirus subfamily, which can cause severe hemorrhagic diseases in neonatal pups as well as mild or subclinical respiratory infections in adult dogs. We examined the effects of cold stress on disease progression of CHV, an alphaherpesvirus, in neonatal puppies. Eight puppies were challenged intranasally with CHV suspension and divided into a cold stress treatment group and a hyperthermal group. Four pups were left uninoculated as controls and divided into cold and hyperthermal groups. In the challenged cold treatment group, all pups showed CHV-related disease within 5 days; pathological changes were observed in organs of puppies showing clinical symptoms. Grossly, numerous petechial red foci were scattered throughout lungs, kidneys, livers, and intestines of all CHV-infected puppies exposed to cold stress. Most puppies showed typical clinical signs and macroscopic lesions, and CHV infection was confirmed by isolation of the virus. However, in the challenged hyperthermal group, only one of the pups showed mild symptoms of CHV-induced disease. None of the puppies in the uninoculated group showed abnormal signs, although they were exposed to cold stress. These findings indicate that cold stress can cause rapid disease progression of CHV, an alphaherpesvirus.

A sensitive and specific polymerase chain reaction to detect Mycoplasma hyopnemoniae using Mycoplasma protein P97 gene / 동물의과학연구지

Mycoplasma (M.) hyopneumoniae is the causative agent of swine enzootic pneumonia, a disease that is prevalent in every country where pigs are raised. In this study, we aimed to develop a sensitive and specific PCR assay to detect M. hyopneumoniae in pigs. The suitability of this PCR assay for the detection of mycoplasmal infection was also tested using clinical lung samples from slaughtered pigs. We developed a probe and M. hyopneumoniae-specific primer pairs, MhyoP-F and MhyoP-R, for the new PCR assay based on regions in the Mycoplasma protein P97 gene that are unique to M. hyopneumoniae. The developed PCR assay was very specific and sensitive for the detection of M. hyopneumoniae. The assay was able to detect the equivalent of 10 pg of target template DNA, which indicates that the assay was very sensitive. In addition, the M. hyopneumoniae PCR assay detected only M. hyopneumoniae and no other Mycoplasma spp. or bacterial species of another genera. Further, the newly developed PCR assay effectively detected M. hyopneumoniae infection in pigs. We suggest that this PCR assay using M. hyopneumoniae-specific primer pairs, MhyoP-F and MhyoP-R, will be useful and effective for monitoring M. hyopneumoniae infection in pigs.