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This report describes a dog infected with Hepatozoon canis, the first canine infection in the Republic of Korea. A 2-year-old intact male Maltese dog presented with anorexia and depression. Physical examinations revealed mild dehydration and hyperthermia (39.8°C), and blood analysis showed pancytopenia. Diff-Quik staining of blood smear specimens showed the presence of ellipsoidal shaped structures (gamonts of H. canis) within a small number of neutrophils. Real-time PCR analysis using whole blood confirmed infection by H. canis. The clinical condition of the dog improved after symptomatic treatment and administration of doxycycline. Although a molecular epidemiologic survey in Korea showed H. canis infection of dogs, to our knowledge this is the first report of a dog infection in Korea molecularly shown to be H. canis.

Sphingolipids have been implicated in the etiology of chronic metabolic diseases. Here, we investigated whether sphingolipid biosynthesis is associated with the development of adipose tissues and metabolic diseases. SPTLC2, a subunit of serine palmitoyltransferase, was transcriptionally upregulated in the adipose tissues of obese mice and in differentiating adipocytes. Adipocyte-specific SPTLC2-deficient (aSPTLC2 KO) mice had markedly reduced adipose tissue mass. Fatty acids that were destined for the adipose tissue were instead shunted to liver and caused hepatosteatosis. This impaired fat distribution caused systemic insulin resistance and hyperglycemia, indicating severe lipodystrophy. Mechanistically, sphingosine 1-phosphate (S1P) was reduced in the adipose tissues of aSPTLC2 KO mice, and this inhibited adipocyte proliferation and differentiation via the downregulation of S1P receptor 1 and decreased activity of the peroxisome proliferator–activator receptor γ. In addition, downregulation of SREBP (sterol regulatory element–binding protein)-1c prevented adipogenesis of aSPTLC2 KO adipocytes. Collectively, our observations suggest that the tight regulation of de novo sphingolipid biosynthesis and S1P signaling plays an important role in adipogenesis and hepatosteatosis.

The anti-inflammatory effects of fermented Ganoderma lucidum water extracts (FGW) were investigated. G. lucidum water extracts (GW) were fermented using the lactic acid bacterium Bifidobacterium bifidum, followed by Lactobacillus sakei subsp. sakei LI033. The effects of GW and FGW on cell proliferation and nitric oxide (NO) production in RAW 264.7 cells were investigated. After cells were treated with lipopolysaccharide, secondary fermented extracts (FGWBL) inhibited NO production more than GW and primary fermented extracts (FGWB) in a dose-dependent manner. FGW inhibited inducible nitric oxide synthesis (iNOS) and production of pro-inflammatory cytokines. In addition to immunological activities, FGW induced expression of heme oxygenase-1 (HO-1). Treatment with ZnPP, a HO-1 inhibitor, counteracted the inhibitory effects of FGW on NO production, indicating that inhibition of NO production by FGW treatment was mediated via HO-1 expression. FGW suppressed pro-inflammatory markers via HO-1 regulation.

Previous rodent studies showed that when injected into the brain, free fatty acids (FFAs) reduced food intake in an oleate-specific manner. The present study was performed to test whether food intake is regulated by circulating FFAs in an oleate-specific manner. Male Wistar rats received an intravenous infusion of olive, safflower, or coconut oil (100mg/h), together with heparin, to raise circulating oleate, linoleate, or palmitate, respectively, and their effects on overnight food intake were evaluated. Compared to other oils, olive oil infusion showed a significantly greater effect to reduce food intake (P0.01). Total caloric intake, the sum of the calories from the diet and infused oil, was significantly reduced with olive oil (P0.01) but not with coconut or safflower oil infusion, suggesting an oleate-specific effect on caloric intake. To further test this idea, different groups of rats received an intravenous infusion of oleate, linoleate, or octanoate (0.5mg/h). Oleate infusion decreased overnight food intake by 26% (P0.001), but no significant effect was seen with linoleate, octanoate, or vehicle infusion (P0.05). The effects of olive oil or oleate infusion could not be explained by changes in plasma glucose, insulin, leptin, or total FFA levels. The olive oil effect on food intake was not reduced in vagotomized rats, suggesting that oleate sensing may not involve peripheral sensors. In contrast, olive oil's effect was attenuated in high-fat-fed rats, suggesting that this effect is regulated (or impaired) under physiological (or pathological) conditions. Taken together, the present study provides evidence that circulating oleate is sensed by the brain differentially from other FFAs to control feeding in rats.

Uncoupling protein-1 (UCP-1) plays a major role in thermogenesis, and has been implicated in the pathogenesis of obesity and metabolic disorders. The purpose of this study was to estimate the effects of A-3826G polymorphism of the UCP-1 gene on the plasma lipid profiles in 190 Korean obese subjects with a body mass index (BMI) more than 30 kg/m2. Height, weight, BMI, wait-to-hip ratio (WHR), obesity index, and body composition were measured and genotype of UCP-1 was analyzed by polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) method. Serum concentrations of fasting glucose, total cholesterol, high-density lipoprotein (HDL) cholesterol, and triglyceride were measured. The frequencies of UCP-1 genotypes were AA type, 22.1%; AG type, 53.7%; and GG type, 24.2%; and the frequency of G allele was 0.51. Among many parameters, diastolic blood pressure (DBP) (P = .023) and low-density lipoprotein (LDL) cholesterol (P = .011) were significantly higher in AG and GG types compared with AA type, whereas HDL cholesterol was significantly lower in GG type compared with other types (P < .05). Atherogenic index was significantly higher in GG type compared with AA type (P = 0.027). LDL-to-HDL cholesterol ratio was significantly increased in the order of AA < AG < GG types (P = .001). When the subjects were divided into a normal group and a hyper-LDL cholesterolemia group by LDL cholesterol level of 3.626 mmol/L (140 mg/dL), the frequency of hyper-LDL cholesterolemia was significantly higher in GG type compared with other types by Fisher's exact (chi-square) test (P = .05). When logistic regression analysis was conducted to find the risk factors of hyper-LDL cholesterolemia, the odds ratio was 4.115 (P = .03) for GG type of UCP-1 gene. These results suggest that the GG type of the UCP-1 gene has a strong association with increased LDL cholesterol level and might be a significant risk factor for hyper-LDL cholesterolemia among Korean obese subjects.