Mitochondrial cytochrome c oxidase as a target site for cephalosporin antibiotics in renal epithelial cells (LLC-PK(1)) and renal cortex.

We reported previously that treatment of the pig kidney proximal tubular epithelial cell line LLC-PK(1) with cephaloridine (CLD) decreased the activity of cytochrome c oxidase in the mitochondria of the cells followed by increases in lipid peroxidation and cell necrosis. In this study, we investigated the effects of CLD on the activity of cytochrome c oxidase in mitochondria isolated from LLC-PK(1) cells and purified the enzyme from mitochondria of the rat renal cortex. The activity of cytochrome c oxidase in the isolated mitochondria from LLC-PK(1) cells was significantly decreased from 1 h after addition of 1 mM CLD.

Ruffini endings are absent from the periodontal ligament of trkB knockout mice.

To clarify the role of neurotrophin receptors in the development of Ruffini endings, periodontal ligaments and trigeminal ganglia of trkA, trkB, and trkC knockout mice were immunostained for protein gene product 9.5 (PGP 9.5), calcitonin gene-related peptide (CGRP), parvalbumin (PV), and calretinin (CR).

Correlation between nuclear action of anthracycline anticancer agents and their binding affinity to the proteasome.

4'-O-tetrahydropyranyladriamycin (THP) showed an approximately 10-fold greater inhibitory effect on DNA synthesis in L1210 mouse leukemia cells than adriamycin (ADM). The intracellular transfer rate and nuclear accumulation of THP were approximately 5-fold higher than those of ADM. The intensity of in vitro inhibition of topoisomerase II activity by ADM was almost the same as that by THP.

The role of the proteasome in apoptosis induced by anthracycline anticancer agents.

To elucidate the involvement of proteasome inhibition in apoptosis induced by anthracycline anticancer agents, we investigated the interaction between the proteasome and anthracycline anticancer agents, and the function of the proteasome in apoptosis. Exposure of L1210 mouse lymphocytic leukemia cells to adriamycin (ADM) or 4'-O-tetrahydropyranyladriamycin (THP) resulted in apoptosis in a dose-dependent manner: 5 microM ADM and 0.5 microM THP induced apoptosis efficiently, but the effects of 10 microM ADM and 5 microM THP were markedly decreased or completely absent.

Mechanism of specific nuclear transport of adriamycin: the mode of nuclear translocation of adriamycin-proteasome complex.

Adriamycin (ADM), an anthracycline anticancer agent, is selectively stored in the nuclei of a variety of proliferating cells, but the precise mechanism of specific nuclear transport of ADM is not well known. Recently, we demonstrated that ADM shows high binding affinity to the cytoplasmic proteasomes of L1210 mouse leukemia cells and that taken up ADM by the cells selectively binds to proteasomes. Nuclear targeting of proteasome in proliferating cells may be mediated by the nuclear localization signals that are found in several of the alpha-type subunits of the 20S proteasome.

Differences in intracellular sites of action of Adriamycin in neoplastic and normal differentiated cells.

Purpose: This study was performed to clarify the intracellular specificity of the differential cytotoxic effects of Adriamycin (ADM) on neoplastic and normal cells.

Methods: The mouse lymphocytic leukemia cell line L1210 and pig kidney proximal tubular epithelial cell line LLC-PK1 were used as neoplastic and normal cells, respectively. These cells were treated with various concentrations of ADM for 24 h and toxicological parameters were determined.

Roles of oxygen radical production and lipid peroxidation in the cytotoxicity of cephaloridine on cultured renal epithelial cells (LLC-PK1).

To clarify the mechanism of cephalosporin nephrotoxicity, the cytotoxic effects of cephaloridine (CER), a nephrotoxic cephalosporin antibiotic, on the pig kidney proximal tubular epithelial cell line (LLC-PK1) were studied in culture. CER increased the content of hydrogen peroxide and decreased the activity of catalase in the treated cells, followed by an increase in the content of lipid peroxide and decreases in both glutathione peroxidase activity and in the non-protein sulfhydryl content. The levels of NADPH-dependent hydrogen peroxide and superoxide anion production by microsomes prepared from LLC-PK1 cells, and by NADPH-cytochrome P-450 reductase purified from the rat renal cortex were significantly increased by paraquat.

Differential toxic effects of gentamicin on cultured renal epithelial cells (LLC-PK1) on application to the brush border membrane or the basolateral membrane.

Aminoglycoside antibiotics are generally accepted to accumulate in renal proximal tubule cells from the luminal surface and show toxic effects on the cells. The binding affinity and membrane permeability of aminoglycoside antibiotics are different at the brush border membrane (BBM) and the basolateral membrane (BLM) of proximal tubule cells. This study was performed, therefore, to investigate the differential effects of the aminoglycoside antibiotic gentamicin (GM) on cultured LLC-PK1 cells, a pig kidney proximal epithelial cell line, after addition to the BBM or the BLM side.

Cephaloridine-induced inhibition of cytochrome c oxidase activity in the mitochondria of cultured renal epithelial cells (LLC-PK(1)) as a possible mechanism of its nephrotoxicity.

To clarify the mechanism of cephalosporin nephrotoxicity, the effects of cephaloridine (CLD), a nephrotoxic cephalosporin antibiotic, on the mitochondria of the pig kidney proximal tubular epithelial cell line LLC-PK(1) were studied in culture. The activity of cytochrome c oxidase in the mitochondria of LLC-PK(1) cells was significantly decreased from 9 h after addition of 1.0 mM CLD to the cultured cells.

In situ photoaffinity labeling of proteasome with photoactive adriamycin analogue.

An intracellular adriamycin (ADM)-binding protein purified from the cytosol of L1210 mouse lymphocytic leukemia cells had a molecular weight of 700-1500 kDa and hydrolyzed Suc-LLVY-MCA. When L1210 cells were incubated with a photoactive ADM analogue, N-(p-azidobenzoyl)-adriamycin (NAB-ADM), most of the NAB-ADM was found to localize in the nuclei. In situ photoaffinity labeling of L1210 cells with NAB-ADM resulted in low protease activity in the cytosol and nuclear extracts and the cells showed selective photoincorporation of NAB-ADM into the proteasome.

Fluoride-induced ultrastructural changes in exocrine pancreas cells of rats: fluoride disrupts the export of zymogens from the rough endoplasmic reticulum (rER).

Influence of fluoride on exocrine pancreas cells was examined morphologically with traditional and prolonged osmium fixation techniques for electron microscopy in the enamel fluorosis model rats injected subcutaneously twice a day with 20 mg/kg body weight of sodium fluoride. Although the rough endoplasmic reticulum (rER) of exocrine pancreas cells in control rats was laminated and oriented parallel to the circumference of the nucleus, the rER of the cells in NaF-treated rats was dilated, disrupted the laminated arrangement, and changed to the globular-shape rER. Many intracisternal granules were formed in these globular-shape rER of the cells exposed to fluoride.

Proprioceptive afferents survive in the masseter muscle of trkC knockout mice.

Peripheral innervation patterns of proprioceptive afferents from dorsal root ganglia and the mesencephalic trigeminal nucleus were assessed in trkC-deficient mice using immunohistochemistry for protein gene product 9.5 and parvalbumin. In trkC knockout mice, spinal proprioceptive afferents were completely absent in the limb skeletal muscles, M.

Implanted tumor growth is suppressed and survival is prolonged in sixty percent of food-restricted mice.

To examine the effect of food restriction on immune functions in the tumor-bearing state, mice were divided into a control group (fed 5.0 g diet/d; 71 kJ/d) and a 60% food-restricted group (fed 3.0 g diet/d; 43 kJ/d) at 8-wk of age, and 4 wk later, L1210 tumor cells were inoculated intradermally.

Mechanism of toxic action of fluoride in dental fluorosis: whether trimeric G proteins participate in the disturbance of intracellular transport of secretory ameloblast exposed to fluoride.

In enamel fluorosis model rats treated with sodium fluoride, secretory ameloblasts of incisor tooth germs exhibited disruption of intracellular trafficking. We examined whether heterotrimeric G proteins participated in the disruption of vesicular trafficking of the secretory ameloblast exposed to fluoride, using immunoblotting and pertussis toxin (IAP)-induced adenosyl diphosphate (ADP)-ribosylation for membrane fractions of the cell. Immunoblotting of crude membranes, post supernatants of the ameloblast, with anti-G(alpha i3/alpha o) and anti-G(alpha s) antibodies showed that Gi3 or Go proteins existed in the secretory ameloblast, but Gs protein did not.

Proteasome is a carrier to translocate doxorubicin from cytoplasm into nucleus.

When an effective concentration of doxorubicin (DXR) was added into L1210 of a mouse leukemia cell line, DXR was rapidly distributed much more in the nuclei than in the other organelle within a few minutes. A [14C]DXR-binding fraction was obtained from the cytosol prepared from L1210 cells. The fraction was adsorbed to hydroxylapatite matrix and eluted from the matrix by 50-150 mM potassium phosphate buffer.

Influence of fluoride on secretory pathway of the secretory ameloblast in rat incisor tooth germs exposed to sodium fluoride.

Fluoride, which is an environmental toxicant, is a potent inducer of mottled enamel in humans and rats. To define the influence of fluoride on the secretory pathway in enamel fluorosis, mottled enamel was induced in the incisor tooth germs of rats by subcutaneous injections of sodium fluoride for 4 days, and then morphological and cytochemical changes of the secretory ameloblast were examined in the tooth germs with HRP-labeled lectin (Con A, GS-I, SBA and PNA) and En3 antibody labeling amelogenins. The accumulation of small vesicles on the route of the secretory pathway between the rER and the Golgi apparatus, disorder of Golgi stacks, and formation of abnormal large granules in distal cytoplasm were seen in the secretory ameloblast.

Effect of repeated administrations of neomycin on the neuromuscular functions and the enhancement of d-tubocurarine action in mice.

Effects of repeated s.c. treatments with 50 mumol (approx.

Relation between the trans-Golgi network and the Golgi stack on development of the Golgi apparatus of the ameloblast in developing rat molar tooth germs.

Background: The problem of how the functional compartments of the Golgi apparatus organizes during cell differentiation to become a well-formed Golgi apparatus is as yet an unresolved issue. This study was designed to define the involvement of the trans-Golgi network (TGN) and the Golgi stack in organizing the Golgi apparatus.

Methods: The distribution of the TGN marker enzyme was examined in the ameloblast of developing rat molar tooth germs using cytochemistry with Co-enzyme A phosphatase (CoA Pase) and cytidine monophosphatase (CMPase).

Changes of lectin staining pattern of the Golgi stack during differentiation of the ameloblast in developing rat molar tooth germs.

Changes of lectin staining patterns in the Golgi stack during cell differentiation were examined in the ameloblasts of developing rat molar tooth germs, using HRP-labeled lectins: Canavalia ensiformis (Con A), Griffonia simplicifolia I (GS-I), Glycine max (SBA), Ulex europeus I (UEA-I), Triticum vulgaris (WGA), and Arachis hypogaea (PNA). The Golgi stacks of the inner enamel epithelial cells and the presecretory ameloblasts were stained with the lectins, although the staining strength and pattern varied among the stacks with each lectin. In some cases, the reaction products for the lectins were observed in most or all saccules of the Golgi stack.

[Cardiotoxicity study of ME2303 with the interval intravenous injections to rats].

Cardiotoxic effects of ME2303 were studied upon interval intravenous administrations to rats in comparison with those of doxorubicin (ADR). ME2303 at two dose levels of 3 and 9 mg/kg/day or ADR at a dose levels of 3 mg/kg/day was injected once a week for 3 weeks to female Sprague-Dawley rats (SPF) of 5-weeks of age. ADR depressed body weight gain, decreased food intake and increased water intake.

Micronucleus test with potassium chromate(VI) administered intraperitoneally and orally to mice.

The effect of route of administration, intraperitoneal (i.p.) or oral gavage (p.

Dactimicin, a new, less toxic aminoglycoside antibiotic active against resistant bacteria.

Dactimicin is a new member of the pseudodisaccharide group of antibiotics. It possesses an unusual N-formimidoyl group which differentiates it from astromicin. Dactimicin is active against wide variety of bacteria, including resistant strains with aminoglycoside-modifying enzymes.

Antibacterial activity and ototoxicity in guinea pigs, and nephrotoxicity in rats of arbekacin.

Arbekacin (HBK), 1-N[(S)-4-amino-2-hydroxybutyl]-3',4'-dideoxykanamycin B, showed broad antibacterial spectra against gram-positive and gram-negative bacteria including Pseudomonas aeruginosa. It was also effective against gentamycin- or tobramycin-resistant bacteria. HBK was resistant to various aminoglycoside-inactivating enzymes except for AAC (2') and AAC (6')-IV, both of which slowly inactivated it.

[A study on the effect of (2"R)-4'-O-tetrahydropyranyladriamycin, a new antitumor antibiotic, on reproduction. III. Its effects on perinatal and postnatal rats].

This paper describes effects of (2"R)-4'-O-tetrahydropyranyladriamycin hydrochloride (THP) on perinatal and postnatal rats. The drug was administered intravenously to female rats at 0.01, 0.