Cultivation of the two perennial brown algae Ecklonia cava and E. stolonifera for abalone feeds in Korea

Ecklonia cava and Ecklonia stolonifera are perennial brown algae that form sea forests off the coast of Korea. Both species are cultured to supply a summer feed for the abalone industry. Recent expansion of the abalone industry in Korea has been bringing an increase in demand for fresh algal supply. Zoospores of the two algae were seeded in October 2006 on seed frames coiled with 100 m of seed fibers. After 2 months of indoor culture and 2 months of intermediate culture, growth and production of the two algae were compared during their main cultivation period from March 2007 to June 2008, in the culture ground in Wando, Korea (34°26′18.68″ N, 127°05′43.88″ E), in situ. Growth rate of E. cava and E. stolonifera was 1.058 and 3.089 mm day^?1, respectively. The mean production of E. stolonifera obtained from the culture ropes was ca. 12 kg wet wt. m^?1 of culture rope while production of E. cava was ca. 3 kg wet wt. m^?1 of culture rope. The difference in production was attributed from the different growth strategies of the two algae, with only E. stolonifera being able to regenerate blades from the holdfast. The ability to regenerate blades from the holdfast therefore makes E. stolonifera the preferred species for biomass production for abalone feeds. In a 120-day feeding experiment, growth rate, weight gain, and survival rate of abalone showed that E. cava and E. stolonifera feeds could provide an alternative feed to Saccharina japonica during summer months.     

Involvement of hydrogen sulfide and homocysteine transsulfuration pathway in the progression of kidney fibrosis after ureteral obstruction

Hydrogen sulfide (H₂S) produced by cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE) in the transsulfuration pathway of homocysteine plays a number of pathophysiological roles. Hyperhomocysteinemia is involved in kidney fibrosis. However, the role of H₂S in kidney fibrosis remains to be defined. Here, we investigated the role of H₂S and its acting mechanism in unilateral ureteral obstruction (UO)-induced kidney fibrosis in mice. UO decreased expressions of CBS and CSE in the kidney with decrease of H₂S concentration. Treatment with sodium hydrogen sulfide (NaHS, a H₂S producer) during UO reduced UO-induced oxidative stress with preservations of catalase, copper-zinc superoxide dismutase (CuZnSOD), and manganese superoxide dismutase (MnSOD) expression, and glutathione level. In addition, NaHS mitigated decreases of CBS and CSE expressions, and H₂S concentration in the kidney. NaHS treatment attenuated UO-induced increases in levels of TGF-β1, activated Smad3, and activated NF-κB. This study provided the first evidence of involvement of the transsulfuration pathway and H₂S in UO-induced kidney fibrosis, suggesting that H₂S and its transsulfuration pathway may be a potential target for development of therapeutics for fibrosis-related diseases.     

Effects of Age and Gender on Sleep Habits and Sleep Trouble for Aged People

The healthy 455 subjects above 60 years of age were questioned on their sleep habit inventory and the morningness-eveningness questionnaire. We analyzed the effects of age and sex on sleep habits and sleep-related trouble. Bedtimes on weekdays and weekends became earlier with aging, and women went to bed significantly later than men did. The length of sleep on weekdays slightly increased with aging, and it was longer for men than for women. The number of urinations and awakenings during nocturnal sleep and the amount of daytime napping increased with aging. The score on morningness-eveningness shifted toward the morning type with aging. In comparison with men, women had significantly longer sleep latency; and a higher percentage of subjects who reported that they sleep for only a short time, have sleep trouble, have received medical treatment for their sleep trouble, and take sleep medication. From these results, we deduced that the phase of sleep shifted forward in subjects above 60 years of age, and they showed frequent interruptions during nocturnal sleep and long daytime napping. We discussed the factor of gender difference in sleep in relation to social and cultural factors, particularly the household activities of women.     

A molecular level prototype for mechanoelectrical transducer in mammalian hair cells

The mechanoelectrical transducer (MET) is a crucial component of mammalian auditory system. The gating mechanism of the MET channel remains a puzzling issue, though there are many speculations, due to the lack of essential molecular building blocks. To understand the working principle of mammalian MET, we propose a molecular level prototype which constitutes a charged blocker, a realistic ion channel and its surrounding membrane. To validate the proposed prototype, we make use of a well-established ion channel theory, the Poisson–Nernst–Planck equations, for three-dimensional (3D) numerical simulations. A wide variety of model parameters, including bulk ion concentration, applied external voltage, blocker charge and blocker displacement, are explored to understand the basic function of the proposed MET prototype. We show that our prototype prediction of channel open probability in response to blocker relative displacement is in remarkable accordance with experimental observation of rat cochlea outer hair cells. Our results appear to suggest that tip links which connect hair bundles gate MET channels.     

Human extracellular superoxide dismutase (EC-SOD) expression in transgenic chicken

Extracellular superoxide dismutase (EC-SOD) is a metalloprotein and functions as an antioxidant enzyme. In this study, we used lentiviral vectors to generate transgenic chickens that express the human EC-SOD gene. The recombinant lentiviruses were injected into the subgerminal cavity of freshly laid eggs. Subsequently, the embryos were incubated to hatch using phases II and III of the surrogate shell ex vivo culture system. Of 158 injected embryos, 16 chicks (G0) hatched and were screened for the hEC-SOD by PCR. Only 1 chick was identified as a transgenic bird containing the transgene in its germline. This founder (G0) bird was mated with wild-type hens to produce transgenic progeny, and 2 transgenic chicks (G1) were produced. In the generated transgenic hens (G2), the hEC-SOD protein was expressed in the egg white and showed antioxidant activity. These results highlight the potential of the chicken for production of biologically active proteins in egg white. [BMB Reports 2013; 46(8): 404-409]     

Curcumin ameliorates TNF-α-induced ICAM-1 expression and subsequent THP-1 adhesiveness via the induction of heme oxygenase-1 in the HaCaT cells

Adhesion molecules such as ICAM-1 are important in the infiltration of leukocytes into the site of inflammation. In this study, we investigated the inhibitory effects of curcumin on ICAM-1 expression and monocyte adhesiveness as well as its underlying action mechanism in the TNF-α-stimulated keratinocytes. Curcumin induced expression of heme oxygenase-1 (HO-1) in the human keratinocyte cell line HaCaT. In addition, curcumin induced Nrf2 activation in dose- and time-dependent manners in the HaCaT cells. Curcumin suppressed TNF-α- induced ICAM-1 expression and subsequent monocyte adhesion, which were reversed by the addition of tin protoporphyrin IX (SnPP), a specific inhibitor of HO-1, or HO-1 knockdown using siRNA. Furthermore, Nrf2 knockdown using siRNA reversed the inhibitory effect of curcumin on the TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes. These results suggest that curcumin may exert its anti-inflammatory activity by suppressing the TNF-α-induced ICAM-1 expression and subsequent monocyte adhesion via expression of HO-1 in the keratinocytes. [BMB Reports 2013;46(8): 410-415]     

C-terminal truncation of a bovine B12 trafficking chaperone enhances the sensitivity of the glutathione-regulated thermostability

The human B₁₂ trafficking chaperone hCblC is well conserved in mammals and non-mammalian eukaryotes. However, the C-terminal ∼40 amino acids of hCblC vary significantly and are predicted to be deleted by alternative splicing of the encoding gene. In this study, we examined the thermostability of the bovine CblC truncated at the C-terminal variable region (t-bCblC) and its regulation by glutathione. t-bCblC is highly thermolabile (T_m = ∼42℃) similar to the full-length protein (f-bCblC). However, t-bCblC is stabilized to a greater extent than f-bCblC by binding of reduced glutathione (GSH) with increased sensitivity to GSH. In addition, binding of oxidized glutathione (GSSG) destabilizes t-bCblC to a greater extent and with increased sensitivity as compared to f-bCblC. These results indicate that t-bCblC is a more sensitive form to be regulated by glutathione than the full-length form of the protein. [BMB Reports 2013; 46(3): 169-174]