Occurrence of Deoxynivalenol, Nivalenol, and Their Glucosides in Korean Market Foods and Estimation of Their Population Exposure through Food Consumption

Major type B trichothecene mycotoxins, including deoxynivalenol (DON), nivalenol (NIV), and their respective glucoside conjugates, deoxynivalenol-3-β-D-glucose (DON3G) and nivalenol-3-β-D-glucose (NIV3G), are present in food products, such as cereals, legumes, and their processed products. Thus, here, DON, NIV, and their 3-β-D-glucosides were monitored in 506 Korean market foods, and exposure to these mycotoxins was estimated in the population consuming these foods. The accuracy and precision of our method, which simultaneously determined four toxins, were 80.1–106.5% and 0.3–12.4%, in four representative food matrices assessed. The incidences of DON, DON3G, NIV, and NIV3G among all food samples tested were 13%, 8%, 12%, and 5%, respectively. The glucoside conjugate with free toxin was found to have the maximum co-occurrence of 49%. The estimated daily intakes of DON, DON3G, NIV, and NIV3G through food intake under four different scenarios were 0.019–0.102, 0.004–0.089, 0.007–0.094, and 0.002–0.095 μg kg−1 body weight (b.w.) day−1, respectively, which are lower than the established health-based guidance values. Overall, our results suggest that the estimated exposure of the Korean population to type B trichothecenes, namely, DON, NIV, and their 3-β-D-glucoside conjugates, may not pose a potential health risk

Mechanosensitive nonselective cation channel facilitation by endothelin-1 is regulated by protein kinase C in arterial myocytes

OBJECTIVE: The mechanosensitive nonselective cation channel (NSC(MS)) and endothelin-1 (ET-1) play critical roles in the regulation of vascular tone. This study was undertaken to investigate the effect of ET-1 on NSC(MS) and on the myogenic response of arteries. METHODS: Cell-attached patch-clamp techniques were applied to rabbit pulmonary and cerebral arterial smooth muscle cells using a 140 mM CsCl pipette and bath solutions (Ca(2+)-free, 1 mM EGTA). Myogenic responses were determined by video analysis of pressurized arteries. RESULTS: The application of negative pressures through the pipette activated NSC(MS), and this was augmented by bath application of ET-1 (1 pM-30 nM). ET-1 lowered the lowest pressure required for NSC(MS) activation. NSC(MS) facilitation by ET-1 was prevented by BQ-123 (1 microM, an ET(A) antagonist) but not by BQ-788 (1 microM, an ET(B) antagonist). Phorbol 12-myristate 13-acetate (PMA, 100 nM), a protein kinase C activator, also increased the activity of NSC(MS). ET-1- or PMA-induced facilitation of NSC(MS) was abolished by GF109203X (10 microM), a protein kinase C inhibitor. Video analysis of pressurized cerebral artery showed inhibition of the myogenic response by the NSC(MS) channel blockers GsMTx-4 (5 microM) and DIDS (3-100 microM). Treatment with ET-1 (10 pM) augmented the myogenic response and this was inhibited by DIDS (30 microM). CONCLUSION: Stimulation of ET-1 receptor (ET(A)) facilitates NSC(MS) via a protein kinase C-dependent signaling pathway in rabbit arterial myocytes. Our findings suggest that NSC(MS) play a role in the myogenic response and its augmentation by ET-1.This work was supported by the Korea Research Foundation funded by theKoreanGovernment (MOEHRD, Basic Research Promotion Fund, KRF-2006-E00021)

Effects of an ethanolic extract of mulberry fruit on blood pressure and vascular remodeling in spontaneous hypertensive rats

Mulberry (Morus alba) has been used in traditional oriental medicine since ages. Recently, it has been reported that mulberry produces hypotensive effects through the eNOS signaling pathway. However, the mechanism underlying the hypotensive effects of mulberry is not entirely clear. Moreover, the effects of mulberry on vascular remodeling events such as hyperplasia, an important etiology in the pathogenesis of hypertension and arteriosclerosis, are also ambiguous. Here, we hypothesized that an ethanolic extract of mulberry fruit (EMF) has beneficial effects on vascular remodeling and produces hypotensive effects. The effects of a 6-week oral administration of EMF were examined in spontaneously hypertensive rats (SHRs). The animals were divided into four groups: normotensive control (Wistar Kyoto rats), non-treated SHR, low-dose (100 mg/kg) EMF-treated SHR, and high-dose (300 mg/kg) EMF-treated SHR. Our results showed that the EMF-diet normalizes hypertension in SHRs in a dose-dependent manner, by preventing smooth muscle proliferation, thickening of the tunica media, and vascular hyper-reactivity. The endothelial functions were not substantially affected by the EMF diet in our experimental setting. In conclusion, we suggest that the mulberry fruit could act as a food supplement for reducing blood pressure in hypertensive subjects through its effects on smooth muscle proliferation and vascular contractility

Genome scan linkage analysis identifies a major quantitative trait loci for fatty acid composition in muscle in an F intercross between Landrace and Korean native pigs

Objective This study was conducted to locate quantitative trait loci (QTL) influencing fatty acid (FA) composition in a large F2 intercross between Landrace and Korean native pigs. Methods Eighteen FA composition traits were measured in more than 960 F2 progeny. All experimental animals were genotyped with 165 microsatellite markers located throughout the pig autosomes. Results We detected 112 QTLs for the FA composition; Forty seven QTLs reached the genome-wide significant threshold. In particular, we identified a cluster of highly significant QTLs for FA composition on SSC12. QTL for polyunsaturated fatty acid on pig chromosome 12 (F-value = 97.2 under additive and dominance model, nominal p-value 3.6×10−39) accounted for 16.9% of phenotypic variance. In addition, four more QTLs for C18:1, C18:2, C20:4, and monounsaturated fatty acids on the similar position explained more than 10% of phenotypic variance. Conclusion Our findings of a major QTL for FA composition presented here could provide helpful information to locate causative variants to improve meat quality traits in pigs