Elevated soluble Fas levels in herpes zoster patients.
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Biomedical subjects
Publications and source records attributed to Y Tamada.
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Localization of nitric oxide synthase (NOS) in the nodose ganglia of the dog, rat and guinea pig was investigated. A double-staining technique of NOS immunohistochemistry and NADPH-diaphorase (NADPHd) histochemistry was used; then the ratio of NADPHd-positive and NOS-positive cells to the total cells was calculated. The distribution of positive cells within the canine nodose ganglion was also investigated. NADPHd-positive neurons were detected in all the ganglia. Three intensities of reactivity to NADPHd histochemistry (strong, weak or negative) were detected in the neurons of all three species. There were more cells that stained strongly for NADPHd in the rat, but fewer in the dog and guinea pig, indicating that a species difference may exist. NADPHd-positive neurons were less abundant in the rostral third of the canine nodose ganglion than in the middle or caudal thirds. NADPHd reactivity was completely co-localized to the cells that demonstrated neuronal NOS immunoreactivity in the canine nodose ganglion. Thus, NADPHd histochemical reactivity may be a reliable marker of NOS in the nodose ganglion.
PURPOSE: To compare calcium ionophore-induced cataract formation and in vitro light scattering in cultured lenses from guinea pig and rabbit. METHODS: Lenses from guinea pig and rabbit were cultured for 5 or 6 days with calcium ionophore A23187. To assess the involvement of calpain in cataract formation; SDS-PAGE, immunoblotting and calcium determinations were performed. For in vitro light scattering, lens soluble proteins from rabbit were hydrolyzed for 24 h by either endogenous lens calpain, or by addition of purified m-calpain and then further incubated for up to 10 days. Light scattering was measured daily at 405 nm. RESULTS: Lenses from younger guinea pigs cultured in A23187 first developed outer cortical opacities followed by nuclear cataract. Total calcium was markedly increased by A23187 in lenses of all ages. Proteolysis of crystallins and alpha-spectrin were observed in nuclear cataract in younger guinea pigs. This was attenuated with age, in association with the attenuation of cataract formation with age. Calpain 80 kDa subunit in the lenses cultured with A23187 was also decreased. Co-culture with SJA6017 or E64d (reversible and irreversible inhibitors of calpain, respectively) reduced A23187-induced nuclear opacities, proteolysis of crystallins and alpha-spectrin, and loss of calpain without affecting increased total calcium. In contrast, rabbit lenses cultured in A23187 did not develop nuclear cataract, although biochemical changes in cultured rabbit lenses were similar to those in cultured guinea pig lenses. Furthermore, no appreciable in vitro light scattering occurred in soluble proteins from rabbit lenses after activation of endogenous m-calpain, or after addition of exogenous purified m-calpain, although crystallins were partially hydrolyzed by calpain. CONCLUSIONS: Both rabbit and guinea pig lenses undergo calpain-induced proteolysis upon elevation of lenticular calcium. However, factors in intact guinea pig lenses may promote light scattering and insolubilization after proteolysis by calpain, but these factors were not functional in rabbit lenses. Discovery of the factors promoting light scatter and insolubilization after proteolysis will help to explain the role of certain crystallin polypeptides in cataract formation.
The purposes of this experiment were to: (1), characterize the peptide aldehyde SJA6017, N-(4-fluorophenylsulfonyl)-L-valyl-L-leucinal, a newly synthesized inhibitor of calpain, and (2) test the effect of SJA6017 in preventing calcium ionophore-induced cataract in cultured rat lenses. In vitro, SJA6017 strongly inhibited purified m-calpain from porcine kidney. Casein zymography confirmed that SJA6017 reversibly bound to the active site of m-calpain. SJA6017 was also confirmed to be a cell-permeable inhibitor in Molt-4 cells. In cultured lenses, SJA6017 reduced nuclear opacity and proteolysis of crystallins and alpha-spectrin caused by calcium ionophore A23187. These results suggested that SJA6017 is a reversible and cell-permeable calpain inhibitor which may possess great efficacy against calcium-induced models of cataract.
The retinal projections to gastrin-releasing peptide (GRP)-expressing neurons in the rat suprachiasmatic nucleus (SCN) were investigated by double immunofluorescence and immunoelectron microscopy. Optic nerve terminals labeled by cholera toxin B subunit (CTb) which was transported from the retinal ganglion cells were intermingled with GRP-immunoreactive cell bodies and processes in the ventrolateral portion of the SCN. Ultrastructural analysis revealed that CTb-immunoreactive retinal terminals made synaptic contacts with GRP-immunoreactive dendritic processes. These results demonstrated that photic information is directly input from the optic nerve to GRP neurons in the SCN and these GRP neurons may be involved in circadian entrainment by light.
Photic induction of NGFI-A gene expression was investigated in the rat suprachiasmatic nucleus (SCN) using in situ hybridization histochemistry. Following light exposure for 30 min, NGFI-A mRNA appeared in the ventral portion of the rostral SCN, in the ventrolateral and in part of the dorsomedial portion at the middle level, and in the lateral portion of the caudal SCN. The distribution of NGFI-A mRNA was wider than that of c-fos mRNA which was confined to the ventrolateral portion at the middle level of the SCN. By double labeling in situ hybridization, approximately half of NGFI-A mRNA-positive cells in the SCN were shown to coexpress vasoactive intestinal peptide (VIP) mRNA, while 16% of cells positive for c-fos mRNA coexpressed VIP mRNA. These findings indicate that the broadness of NGFI-A mRNA and c-fos mRNA expression after photic stimulation are different. NGFI-A gene induced in these cells of the SCN including VIP neurons may be involved in circadian entrainment by light.
A human liver 3 alpha-hydroxysteroid dehydrogenase isoenzyme, a member of the aldo-keto reductase family, shows a marked preference for NADP(H) over NAD(H), and is activated by sulphobromophthalein, which increases the Km values for both NADP(H) and substrates. Here we report kinetic alterations in binding of the coenzymes and the activator to the enzyme caused by site-directed mutagenesis of Lys-270 and Arg-276, which are strictly conserved among the aldo-keto reductase family of enzymes. The mutated enzymes, K270M and R276M, showed increases in the Km for NADP+ of 22- and 290-fold respectively; the Km for alcohol substrate and the kca1 of the NADP(-)-linked reaction were also elevated, by 9- and 5-fold respectively. No kinetic constant of the NAD(+)-linked reaction was altered by more than 3-fold. Calculation of the free-energy changes showed that the 2'-phosphate group of NADP+ contributes 16.3 kJ/mol (3.9 kcal/mol) of binding energy to its interaction with the wildtype enzyme, and the mutagenesis to K270M and R276M destabilized the binding energy of NADP+ by 6.3 and 13.0 kJ/mol (1.5 and 3.1 kcal/mol) respectively. In addition, the mutations attenuated enzyme activation by sulphobromophthalein, which bound to the mutant enzymes as an inhibitor. The inhibition for the R276M mutant was competitive with respect to NADP+ and non-competitive with respect to the substrate, whereas that for the K270M mutant was mixed-type, showing activation at coenzyme concentrations greater than 20 x Km. These results suggest that the two basic residues in the 3 alpha-hydroxysteroid dehydrogenase isoenzyme play crucial roles in binding both the negatively charged 2'-phosphate group of NADP+ and the sulphonic groups of sulphobromophthalein.
Age-related decreases in circadian oscillating activity are speculated to be one of the causes of psychiatric symptoms. To explore the effects of aging on vasoactive intestinal peptide (VIP) synthesis in the suprachiasmatic nucleus (SCN), we investigated the changes in VIP mRNA levels in aged rats compared with young-adult rats under a light/dark cycle using in situ hybridization combined with microcomputer-based imaging analysis. In the young-adult rats, total signals of VIP mRNA in the light-phase showed a significant decrease compared with those on the dark-phase. The VIP signal level in the aged rats was markedly lower than that in young-adults in both light and dark phases. Moreover, in the aged rats, there were no significant differences in VIP mRNA level between the light and dark phases. These results suggest that gene expression of VIP neurons, a main component of the circadian oscillating system, becomes disturbed in the aged rat brain.
The purpose of the present investigation was to compare in vitro light scattering in the soluble proteins from rodent lenses after hydrolysis by the calcium-activated protease, m-calpain (EC 3.4.22.17). Light scattering was measured in solutions of lens proteins from mice, rats, and guinea pigs after activation of endogenous m-calpain or after addition of purified m-calpain. We found for the first time that, in addition to rat, crystallins from another rodent lens, young mouse, were susceptible to calpain-induced light scattering. As in rats, aging of mouse lens prevented calpain-induced light scattering. Although crystallins from guinea pig lens were also partially hydrolysed by calpain, appreciable light scattering did not occur. Limited proteolysis may cause common changes in the biophysical properties of mouse and rat crystallins to decrease their solubility. Discovery of the nature of these biophysical changes may help our understanding as to why crystallins precipitate under cataractous conditions.
Linear focal elastosis in three young Japanese men is described. The lesions are asymptomatic palpable yellow strialike bands extending horizontally across the middle and lower parts of the back. They are histologically composed of many fine wavy bundles of elastic fibers separating the dermal collagen bundles. Electron microscopy demonstrates numerous elongated and fragmented elastic fibers.
Pitted keratolysis (PK) has been reported to be more common among bare-footed people living in tropical regions. It is now known that the disease is not limited to the tropics but has a world-wide distribution. However, no study has previously been performed analysing the clinical manifestations of the disease in temperate countries. A survey of 53 patients revealed several distinctive clinical features. Hyperhidrosis is the most frequently observed symptom of this condition. Malodour and sliminess of the skin are also distinctive features, evident in 88.7% and 69.8% of the cases, respectively. The most common sites of onset of PK are the pressure-bearing areas, such as the ventral aspect of the toe, the ball of the foot and the heel. The next most common site is a friction area, the interface of the toes. Lesions are rarely seen on the non-pressure-bearing locations. Some of the primary lesions originate as a small defect along the plantar furrow, which gradually grows into the characteristics crateriform pit. Several clinical features are helpful in diagnosing PK.
The participation of apoptotic cell death of neutrophils in the development of skin lesions of patients with anaphylactoid purpura was examined by the in situ specific labeling of fragmented DNA. In the early stage of the skin lesions, there were few positively stained nuclei in infiltrating cells. The number of positive cells increased markedly in the fully developed stage of the lesions. A number of neutrophils were stained positively. Finally, a few fragmented nuclei were still positive in the late stage of the lesions. It was therefore suggested that fragmentation of neutrophils in the skin lesions from the patients might be due to apoptosis. Inducible nitric oxide synthase and nitrotyrosine were detected in infiltrates, and interleukin-8 was also detected in vascular endothelial cells in those skin lesions. The roles of nitric oxide and interleukin-8 in the apoptosis of neutrophils are discussed.
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Mitochondrial density in neurons of the dorsolateral region of the ventral horn at the L5 spinal cord segment in rats was examined using electron microscopy. The gamma motoneurons had a higher density of mitochondria (25.1 +/- 4.2%, n = 19) in the cytoplasm compared to the alpha motoneurons which had a mitochondrial density of 19.4 +/- 4.5% (n = 38). An inverse relationship between cell body size and mitochondrial density was found for alpha (n = 38) and alpha plus gamma (n = 57), but not for gamma (n = 19), motoneuron populations. The higher densities of mitochondria in the smaller neurons correspond well with their metabolic properties since the smaller neurons have the highest oxidative enzyme activities.
We investigated the effects of Sho-saiko-to, the most commonly used herbal medicine in Japan, on the production of interleukin (IL)-1 alpha by cultured human epidermal keratinocytes. IL-1 alpha production was significantly promoted by treatment with 100 or 500 micrograms/ml Sho-saiko-to for 24 or 48 hr. Expression of IL-1 alpha receptors was the most markedly upregulated after treatment with 500 micrograms/ml Sho-saiko-to for 24 hr and with 100 or 500 micrograms/ml for 48 hr; these cells showed the characteristics of multilayered differentiated keratinocytes. The presence of an anti-IL-1 alpha antibody during the treatment with 500 micrograms/ml of Sho-saiko-to for 24 or 48 hr or with 100 micrograms/ml for 48 hr significantly down-regulated the synthesis by the keratinocytes and induced damages in them. Keratinocytes treated with Sho-saiko-to might produce IL-1 alpha and express IL-1 alpha receptors. IL-1 alpha may regulate the proliferation and differentiation of keratinocytes after Sho-saiko-to treatment. These findings suggest that Sho-saiko-to enhances the autocrine growth mediated by IL-1 alpha.
Using glial fibrillary acidic protein (GFAP) immunohistochemistry, and electron microscopy, we examined changes in the features of astrocytes in the dentate gyrus of the hippocampal formation after high-dose chronic toluene inhalation (2000 ppm, 4 h/day) for 1 month. In toluene-treated rats, the numbers of GFAP-immunoreactive (IR) astrocytes were not changed, whereas the area and intensity of GFAP-IR processes were increased markedly in the dentate gyrus. In addition, dense, thick and highly-stained GFAP-IR processes appeared entering into the granular cell layer, compared with those of controls. At the electron microscopic level, numerous astrocytic processes with high electron density intervened between the granular cells. These results suggest that high-dose of chronic toluene exposure induces morphological changes in astrocytes in the dentate gyrus of the hippocampal formation.
We previously isolated three monomeric dihydrodiol dehydrogenases, DD1, DD2 and DD4, from human liver, and cloned a cDNA (C9) thought to encode DD2, which is identical with those for human bile-acid-binding protein and an oxidoreductase of human colon carcinoma HT29 cells. In the present study we have provided evidence that the C9 cDNA clone encodes DD1, not DD2. A recombinant enzyme expressed from the cDNA in a bacterial system was purified, and its catalytic properties, bile-acid-binding ability and primary sequence were compared with those of the hepatic dihydrodiol dehydrogenases. The results show that DD1 encoded by C9 possesses prostaglandin F synthase activity but low affinity for lithocholic acid, whereas DD2, showing differences of six amino acid residues from the DD1 sequence, exhibited high-affinity binding for the bile acid. Refined relationship between dihydrodiol dehydrogenases and their related proteins of human tissues is proposed.