TGFß1 signaling protects chondrocytes against oxidative stress via FOXO1-autophagy axis.

OBJECTIVE: The forkhead box O1 (FOXO1) transcription factor is a key regulator of autophagy. In chondrocytes, reduced FOXO1 expression with aging causes osteoarthritis due to dysfunction of autophagy, but the mechanisms underlying regulation of FOXO1 expression and the reduction in expression with aging remain unclear. We investigated the mechanism by which transforming growth factor ß1 (TGFß1) signaling regulates the FOXO1-autophagy axis. METHODS: Expression of FOXO1 was measured in chondrocytes after TGFß1 treatment. Immunohistochemistry was performed to estimate the levels of activin receptor-like kinase 5 (ALK5) and FOXO1 in the knee joints of young, middle-aged and old mice. The effects of the ALK5 inhibitor and SMAD3 or SMAD2 knockdown on FOXO1 expression were evaluated. The role of TGFß1 in autophagy after hydrogen peroxide (H2O2) treatment was analyzed. The protective effect of TGFß1 against H2O2 treatment was assessed by cell viability assay and TUNEL assay. RESULTS: TGFß1 promoted the expression of FOXO1 mRNA and protein. Both ALK5 and FOXO1 expression decreased with aging. ALK5 inhibition and SMAD3 knockdown suppressed induction of FOXO1 expression by TGFß1, whereas SMAD2 knockdown increased it. TGFß1 promoted the expression of microtubule-associated proteins 1A/1B light chain 3B (LC3)-I protein via the SMAD3-FOXO1 pathway. Furthermore, under H2O2 treatment, TGFß1 promoted expression of LC3-II. TGFß1 pretreatment suppressed cell death of chondrocytes following H2O2 treatment, but this protective effect was abolished by FOXO1 knockdown. CONCLUSIONS: TGFß1 protects chondrocytes against oxidative stress via the FOXO1-autophagy axis, and a reduction in ALK5 expression might cause reduced FOXO1 expression with aging.

Use of gonococcal agar medium for preparation of antigen of Haemophilus paragallinarum hemagglutinin.

Some solid media for antigen preparation of Haemophilus paragallinarum (HPG) hemagglutinin (HA) were studied. When HA activities of HPG strain 221 cultivated on chicken meat infusion (CMI) and gonococcal (GC) agar media were compared, the titer of the GC agar medium appeared faster and was higher than the titer on the CMI agar medium. For both agar media, the HA titer and growth increased with the concentration of the chicken serum added. In addition, HA activity on GC agar medium showed a higher titer than activity on other media, such as brain-heart infusion, Trypticase soy, blood, and Kato's agar media. When various HPG strains were inoculated onto GC agar medium, HA titers in strains 0083 and F were equal to that in strain 221. These results confirm that the GC agar medium is useful for preparation of HA antigen of HPG.

Determination of types 1 and 2 hemagglutinins in serotypes of Hemophilus paragallinarum.

Type 1 hemagglutinin (HA) of Hemophilus paragallinarum (HPG) was found only in Page's serotypes A and B and in Kato's serotypes I and III of HPG. Type 2 HA was found in all serotypes of HPG. Hemagglutination-inhibition test revealed no serological differences among the type 2 HA of Kato's serotypes.

Stability, specific binding activity, and plasma concentration in mice of an oligodeoxynucleotide modified at 5'-terminal with poly(ethylene glycol).

Oligodeoxynucleotide (ODN) composed of 15 nucleotides was modified at 5'-terminal phosphate with hexylamine linker and chemically activated poly(ethylene glycol). This derivative showed improved characteristics in terms of enzymatic stability, binding activity, and in vivo retention in mouse. The data are discussed in comparison with those of corresponding unmodified and phosphorothioate ODNs.

Environmental risk assessment of surfactants: fate and environmental effects in Lake Biwa basin.

Environmental risk incurred with the use of synthetic surfactants is dealt with in this paper. The background and necessity of risk management related to surfactant usage in the Lake Biwa basin are introduced, as well as a research scheme that acknowledges risks in three sub-processes--consumption and discharge, fate in aquatic environment, and ecotoxicological response of linear alkylbenzene sulfonate (LAS). The ayu (Plecoglossus altivelis) has been selected as the significant biological target in the basin. Results of a field survey of the behavior of LAS along streams flowing down to the lake are presented. Included are the estimation and verification of an original unit of surfactant consumption per capita per day based on LAS and MBAS concentrations observed in diurnal monitoring. A simulation model representing the flowdown process of LAS dynamically is formulated, with which longitudinal dispersion, settling, and modified biodegradation of LAS are evaluated in the field survey. On the basis of the research scheme described above, ecotoxicological laboratory tests on ayu have been carried out. The special significance of acute and subchronic effects on ayu in various life stages exposed to low concentrations of LAS can be recognized. It has been concluded that the LC50 of young ayu is not greater than 0.1 ppm under the disadvantageous condition of high temperature or extreme hardness even in normal ranges of environmental indicators. An advanced plan of risk management for surfactant usage is proposed based on methods of elevated risk, comparative risk, risk--benefit, and balanced risk. The occurrence and magnitude of risk phenomena in each subdivided basin adjacent to the lake are identified, taking into consideration features such as (1) the spawning place of ayu and aquafarms, (2) COD and MBAS concentrations and their tolerable levels in current regulation of stream pollution, (3) socioeconomic perspectives including recreational activities and voluntary actions to improve the neighborhood environment, and (4) future preparation of measures for resolving technological risk including sewerage construction. Because LAS concentrations in several rivers exceed the tolerable level of the most delicate life stage of ayu, latent environmental effects can be suggested. It is concluded therefore that it is necessary to establish a water quality goal related to surfactants that takes patterns of water use and conservation of the ecosystem in the local environment into consideration. These judgments are followed by formulation of the "requirement" for environmental management practice for the Lake Biwa administration.