Estimation of aldehyde oxidase activity in vivo from conversion ratio of N1-methylnicotinamide to pyridones, and intraspecies variation of the enzyme activity in rats.

The in vivo conversion ratio of N1-methylnicotinamide (NMN) to N1-methyl-2-pyridone-5-carboxamide (2-PY) and N1-methyl-4-pyridone-3-carboxamide (4-PY) as a parameter for the estimation of aldehyde oxidase level in rats was examined. NMN and its pyridones (2-PY and 4-PY) are usually detected in the urine of rats. When we measured the ratio of the amount of pyridones to the total amount of NMN and pyridones (RP value) in the urine of rats, marked intraspecies variations were observed. The variation in RP value among strains was closely related to the differences of liver aldehyde oxidase activity measured with NMN as a substrate. RP values after administration of NMN to different strains of rats confirmed the existence of strain differences of aldehyde oxidase activity in vivo. We demonstrated that measurements of NMN and its pyridones usually excreted in the urine can be used to predict the in vivo level of aldehyde oxidase.     

Effects of poly-L-arginine on the permeation of hydrophilic compounds through surface ocular tissues

We investigated whether poly-L-arginine (PLA) could improve permeation of the hydrophilic compounds, FITC-labeled dextran (MW 3800, FD-4) and pyridoxamine, through ocular surface tissues. Samples of cornea, conjunctiva, or conjunctiva/sclera composite from Japanese white rabbits were mounted in Ussing chambers to measure FD-4 and pyridoxamine permeation and transepithelial electric resistance (TEER). The integrity and viability of the conjunctiva were assessed by chronological TEER monitoring and MTT assay, respectively. The permeability coefficient (Papp) of FD-4 in the cornea, conjunctiva, and conjunctiva/sclera composite was increased by the addition of PLA (MW 38 kDa, PLA (50) at 0.1 mg/ml by 6.81-, 9.78-, and 7.91-fold, respectively. The Papp of pyridoxamine was also increased in the presence of PLA (50) by 7.98-, 4.67-, 8.31-fold, respectively. A corresponding reduction in TEER was observed in all tissues. However, the reduced TEER in the case of the conjunctiva had recovered to ca. 70% 120 min after replacing the mucosal fluid with fresh bicarbonated Ringer's solution. MTT assay results indicated that treatment of the conjunctiva with 0.1 mg/ml PLA (50) did not change the production of formazan compared to that without PLA (50), indicating that the conjunctival viability is not significantly affected by PLA (50). Our findings suggest that PLA may be useful in promoting the ocular delivery of hydrophilic drugs without producing significant epithelial damage.     

Dietary intake, neutrophil fatty acid profile, serum antioxidant vitamins and oxygen radical absorbance capacity in patients with ulcerative colitis

Nutrition may play an important role in the pathogenesis and treatment of ulcerative colitis. Several studies suggest an association between dietary factors and the onset of ulcerative colitis; however, only few studies have examined the relationship between dietary intake and relapse of ulcerative colitis. The aim of this study was to assess the dietary intake and antioxidative capacity of ulcerative colitis patients and to elucidate the efficacy of dietary therapy for ulcerative colitis. Dietary intake, fatty acid composition of phospholipids in plasma and neutrophils, serum fat-soluble vitamin levels, and oxygen radical absorbance capacity were analyzed in 29 ulcerative colitis patients (7 males and 22 females), who were treated at the Department of Gastroenterology, Okayama University Hospital. Total fat intake, fat energy ratio and linoleic acid intake were significantly lower, while protein and carbohydrate intakes were significantly higher, in the patients than age- and sex-matched controls. In the neutrophil phospholipids of ulcerative colitis patients, significantly higher levels of linoleic aicd and arachidonic acid and a lower level of eicosapentaenoic acid were observed. The concentrations of serum retinol and beta-carotene but not alpha-tocopherol were significantly lower and serum oxygen radical absorbance capacity was also lower than in the controls. Significant correlations between serum oxygen radical absorbance capacity and retinol (r = 0.567, p = 0.0031), alpha-tocopherol (r = 0.560, p = 0.0036) and beta-carotene (r = 0.440, p = 0.0279) concentrations were observed in the ulcerative colitis patients. A diet restricting the intake of linoleic acid and supplemented with eicosapentaenoic acid and antioxidative vitamins may be recommendable for the nutritional management of ulcerative colitis patients.     

Genetic characterization of hantaviruses transmitted by the Korean field mouse (Apodemus peninsulae), Far East Russia

In an epizootiologic survey of 122 rodents captured in Vladivostok, Russia, antibodies positive for hantavirus were found in Apodemus peninsulae (4/70), A. agrarius (1/39), and Clethrionomys rufocanus (1/8). The hantavirus sequences identified in two seropositive A. peninsulae and two patients with hemorrhagic fever with renal syndrome (HFRS) from the Primorye region of Far East Russia were designated as Solovey and Primorye, respectively. The nucleotide sequences of the Solovey, Primorye, and Amur (obtained through GenBank) sequences were closely related (>92% identity). Solovey and Primorye sequences shared 84% nucleotide identity with the prototype Hantaan 76-118. Phylogenetic analysis also indicated a close relationship between Solovey, Primorye, Amur, and other viruses identified in Russia, China, and Korea. Our findings suggest that the Korean field mouse (A. peninsulae) is the reservoir for a hantavirus that causes HFRS over a vast area of east Asia, including Far East Russia.     

Differences in the priming effect of various clades/subclades of inactivated H5N1 vaccine for booster injection with heterologous clades of vaccine strains

The prime-boost response induced by different combinations of four H5N1 vaccines (NIBRG-14 (clade 1), Indo05/2005(H5N1)/PR8-IBCDC-RG2 (clade 2.1), A/Bar-Headed Goose/Qinhai Lake/1A/05 SJ163222 (clade 2.2), and Anhui01/2005(H5N1)-PR8-IBCDC-RG5 (clade 2.3.4)) was evaluated in mice. Clade 1-primed BALB/c mice showed a booster response to all of the other three H5N1 vaccines. Clade 2.2 vaccine was also a good priming vaccine. However, mice primed with clade 2.1 or clade 2.3.4 vaccine did not respond to booster injection with clade 1 vaccine, suggesting that priming might actually inhibit the booster response with some combinations of vaccines belonging to different clades. Analysis of the mechanism involved showed that lymphocytes from primed mice secreted comparable amounts of cytokines with any combination of priming and booster vaccines. Therefore, impairment of B cell immunity specific to certain booster strains may have been involved.     

Anti-diabetic effects including diabetic nephropathy of anti-osteoporotic trace minerals on diabetic mice

Objective

In our previous study to evaluate the effects of soluble silicon (Si) on bone metabolism, Si and coral sand (CS) as a natural Si-containing material suppressed peroxisome proliferator-activated receptor γ (PPARγ), which regulates both glucose and bone metabolism and increases adipogenesis at the expense of osteogenesis, leading to bone loss. In this study, we investigated the anti-diabetic effects of bone-seeking elements, Si and stable strontium (Sr), and CS as a natural material containing these elements using obese diabetic KKAy mice.

Methods

Weanling male mice were fed diets containing 1% Ca supplemented with CaCO₃ as the control and CS, and diets supplemented with 50 ppm Si or 750 ppm Sr to control diet for 56 d. The mRNA expressions related to energy expenditure in the pancreas and kidney were quantified by real-time polymerase chain reaction.

Results

At the end of feeding, plasma glucose, insulin, leptin, and adiponectin levels decreased significantly in three test groups, while pancreatic PPARγ and adiponectin mRNA expression levels increased significantly toward the normal level, improving the glucose sensitivity of β-cells and inducing a significant decrease in insulin expression. The renal PPARγ, PPARα, and adiponectin expression levels, histologic indices of diabetic glomerulopathy, and plasma indices of renal function were also improved significantly in the test groups.

Conclusion

Taken together, anti-osteoporotic trace minerals, Si and Sr, and CS containing them showed novel anti-diabetic effects of lowering blood glucose level, improving the tolerance to insulin, leptin, and adiponectin, and reducing the risk of glomerulopathy through modulation of related gene expression in the pancreas and kidney.     

Role of vitronectin receptor-type integrins and osteopontin in ischemia-induced retinal neovascularization

PURPOSE: It has been reported that vitronectin receptor-type integrins mediate vascular cell proliferation and migration. In this study, we investigated the expression of vitronectin receptor-type integrins and osteopontin in ischemia-induced retinal neovascularization, and examined the role of osteopontin in angiogenesis as a ligand of vitronectin receptor-type integrins. METHODS: Retinal neovascularization was produced by exposing C57BL/6J mice to 75% oxygen from postnatal day (P) 7 to P12. Expression of vitronectin receptor-type integrins and osteopontin was assessed by Northern blot analysis, in situ hybridization, and immunofluorescence. The role of osteopontin in retinal angiogenesis was evaluated by tube formation assay using cultured bovine retinal microcapillary endothelial cells. RESULTS: In the murine model, integrin alpha(v) mRNA was increased from P14 with a 2.6-fold peak response observed on P19, when retinal neovascularization was remarkable. Indirect immunofluorescence for vitronectin receptor-type integrins revealed prominent expression of integrin alpha(v)beta3/beta5 in the neovascular endothelial cells. Osteopontin mRNA was increased from P14, with a 2.0-fold peak response observed on P19. In situ hybridization demonstrated localization of osteopontin mRNA in neovascular tufts. Vascular endothelial growth factor-induced tube formation (8.3 +/- 0.6 mm/field) was inhibited significantly by treatment with anti-osteopontin antibody (4.8 +/- 0.7 mm/field, P <.001). CONCLUSIONS: These data suggest that increased expression of both vitronectin receptor-type integrins and osteopontin in ischemic retina contribute to vascular endothelial cell proliferation and to retinal vascular formation by promoting interaction between endothelial cells and extracellular matrix, which leads to retinal neovascularization.