Extra-weak chemiluminescence of drugs. XIV. Quenching effects of anthraquinones on the extra-weak chemiluminescence from lipid peroxidation in rat brain homogenates]

Quenching effects of anthraquinones on the extra-weak chemiluminescence (CL) derived from lipid peroxidation in rat brain homogenates were investigated. Such anthraquinone derivatives as emodin, rhein, and alizarin quenched the CL, while anthraquinone did not quench the CL. A linear relationship between CL-quenching activity and inhibitory rate of malondialdehyde production of various compounds was demonstrated. This technique is useful for the screening method of antioxidants.     

Difficulty in using RP, PL, and EW factors in the Japanese classification of pancreatic carcinoma

The classification of pancreatic carcinoma by the Japan Pancreas Society reflects the prognosis of each stage better than does the TMN classification. On the other hand, there are too many factors to examine in the Japanese system, some of which are difficult to use and have low accuracy in pre- and/or intraoperative diagnosis (RP and PL), and their analysis requires various specimen handling procedures (EW). We propose that: 1) a simple, easy decision flow chart be established for ew and 2) EW/ew be designated as (-) or (+) and for EW/ew (+) cases other factors (ly, v, pl, and direct tumor invasion) be added (for example, ew (+)-pl).     

Thyroglobulin gene abnormalities

Congenital hypothyroidism is caused either by abnormal development of thyroid glands or by inborn errors of thyroid hormone synthesis. Thyroglobulin mutations which caused overt Cretins with physical and mental development impairment were once believed rare. However, since the discovery of mild hypothyroidism due to thyroglobulin mutations, 54 cases from 43 families were identified in Japan. The patients presented either transient elevation of serum TSH during infancy or growing giant goiters from childhood. Among 15 patients who were born after initiation of neonatal screening in 1979, 13 patients were identified by high serum TSH. In contrast, the major manifestation in patients born before 1979 is persistent growth of goiters with euthyroidism or subclinical hypothyroidism. Among 25 mutations, Cys1264Arg and Cys1077Arg are hot spots. The Cys1264Arg patients were found all over Japan, but the Cys1077Arg patients were confined to a small village of a southern island in Japan. The occurrence of the thyroglobulin mutations in the general population is 1/67,000. The pathogenesis of abnormal thyroglobulin is defective intracellular transport. The histological findings include empty colloid in the follicles and distended ER filling the entire cytoplasm of the thyrocytes. An in vitro expression study showed that abnormal thyroglobulin was not secreted from cultured cells. Because of persistent growth of the thyroid, 25 patients underwent surgical treatment. Among them, 11 patients suffered from thyroid cancers, most of which were of the papillary type. We found two BRAF activating mutations Val599Glu and Cys600Gln in five patients tested. In conclusion, we found many patients with thyroglobulin mutations in Japan. They were found by high serum TSH at neonatal screening or persistent growth of goiters in adults. Surgical treatments were inevitable, and 40% of the removed thyroids contained thyroid cancers, some of which were caused by activating mutations of the BRAF gene.     

A pharmacodynamic and pharmacokinetic study of fluoropyrimidines in a nude mouse system and in postoperative patients with gastric cancer

To evaluate the effect of the oral fluoropyrimidines, tegafur and uracil (UFT) and 5-fluorouracil (5-FU), a pharmacodynamic analysis was conducted using a nude mouse system and patients. In the nude mouse system, UFT and 5-FU showed similar marginal effects against the human tumor xenograft Co-4, and the concentration of 5-FU in serum 1 h after the last administration being 0.04 g/ml, which was assumed to be the minimum effective concentration. (MEC). Postoperative patients were subdivided into three groups, being: those who underwent subtotal gastrectomy and received UFT; those who underwent subtotal gastrectomy and received 5-FU; and those who underwent total gastrectomy and received UFT. In the UFT groups, the concentration of 5-FU in the portal and peripheral blood showed similar elimination in terms of the peak concentration (Cmax) and the area under the curve (AUC). In the 5-FU groups, the AUC and Cmax were significantly higher in portal blood than peripheral blood. The concentrations in the portal blood of the 5-FU group and in the portal and peripheral blood of the UFT group were significantly higher than the MEC (0.04 g/ml). From these pharmacodymamic data, it was concluded that postoperative chemotherapy with oral fluoropyrimidines can achieve the MEC in portal and peripheral blood.This paper was presented, in part, at the 28th and 29th Congresses of the Japan Society for Cancer Therapy in Tokyo and Osaka.     

Epidermal FABP (FABP5) regulates keratinocyte differentiation by 13(S)-HODE-mediated activation of the NF-κB signaling pathway

Fatty acid-binding proteins (FABPs) are postulated to serve as lipid shuttles that solubilize hydrophobic fatty acids and deliver them to appropriate intracellular sites. Epidermal FABP (E-FABP/FABP5) is predominantly expressed in keratinocytes and is overexpressed in the actively proliferating tissue characteristic of psoriasis and wound healing. In this study, we found decreased expression of the differentiation-specific proteins keratin 1, involucrin, and loricrin in E-FABP(-/-) keratinocytes relative to E-FABP(+/+) keratinocytes. We also determined that incorporation of linoleic acid was significantly reduced in E-FABP(-/-) keratinocytes. Although linoleic acid did not directly affect keratinocyte differentiation, keratin 1 expression was induced by the linoleic acid derivative 13(S)-hydroxyoctadecadienoic acid (13(S)-HODE), and this induction was concomitant with increased NF-κB activity. In E-FABP(-/-) keratinocytes, the expression of 13(S)-HODE and the subsequent induction of NF-κB activity was lower than in wild-type keratinocytes. The reduction of linoleic acid in E-FABP(-/-) keratinocytes led to decreased cellular 13(S)-HODE content, resulting in decreased keratin 1 expression through downregulation of NF-κB activity. The regulation of fatty acid metabolism by E-FABP during keratinocyte differentiation suggests that E-FABP may have a role in the pathogenesis of psoriasis.     

Alterations of gluconeogenesis by ischemic renal injury in rats.

This study was designed to determine changes in one metabolic function, gluconeogenesis (GLG), after ischemic renal injury. Tubule suspensions were prepared by collagenase treatment of SD rat kidneys on 1, 3, and 7 days after left renal artery and vein occlusion for 0-90 min and incubated in Krebs-Henseleit buffer with or without 2 mM pyruvate or malate aerobically. Glucose contents were assayed photometrically. On days 1 and 3 after ischemia for longer than 60 min, serum creatinine levels rose significantly. The tendency of increase of GLG was observed on days 1 and 3 after 10-60 min of ischemia. GLG increased significantly on day 1 after 30-min ischemia. On the other hand, GLG decreased significantly on day 1 after 90-min treatment. Morphologic damage was limited to the corticomedullary region on days 1 and 3 after ischemic times of 30 and 60 min. These results suggest that renal GLG is stimulated to supply energy for ATP decrease by ischemia and for further regeneration in extraproximal segments along the nephron.     

Augmentation of mouse immune functions by dietary restriction: an investigation up to 1 year of age

Mice fed a 40% restricted diet until 1 year of age showed a 35% drop in body weight and markedly lower weights in the central lymphoid organs such as spleen and thymus than those of unrestricted mice. In contrast, the percentage of splenic Thy 1.2+ T cells was dramatically increased by dietary restriction. Splenic Ly 1+ T cells were also increased in the restricted mice. Spleen cells of the restricted mice revealed significantly higher responses not only in macrophage (MP)-dependent responses such as concanavalin A response and mixed-lymphocyte reaction but also in MP-independent T cell responses to recombinant interleukin 2 even at 1 year of age. These results strongly suggest that dietary restriction causes an enrichment of Thy 1.2+ T cells in spleen and augments the functions of T cells in mice.     

A factor potentiating antibody formation spontaneously produced by splenic T cells of MRL/MP-lpr/lpr mice

Splenocytes of MRL/l mice, one of the murine lupus strains, were found to produce a factor(s) which potentiates antibody formation. This factor was produced by splenocytes of young MRL/l mice and cell-sorting experiments by flow cytometry indicated that Thy 1.2+ cells were producing the factor. The approximate molecular weight of the factor was found to be 35,000-45,000 daltons and its pI value was between 3.3 and 3.8. It was also demonstrated that this factor is distinct from interferons, interleukins (IL-1, IL-2, IL-3) and B cell differentiation factors.