Biomedical subjects

N Motohashi

Publications and source records attributed to N Motohashi.

At least 181 records · Page 10Linked to original sources

PubMedDate not supplied

Antiplasmid and carcinogenic molecular orbitals of benz[c]acridine and related compounds.

Effect of K- and L- molecular orbital regions on expression of antiplasmid and carcinogenic activity was studied with various benz[c]acridine derivatives, tricyclic compounds (acridine orange, phenothiazines) and dibenzoazepine (imipramine). Antiplasmid compounds showed the out-of-phase of molecular orbital in the L-region. On the other hand, mutagenic and carcinogenic compounds showed the out-of-phase in the L-region, and their energy was accumulated in the K-region of the molecular orbitals. The present study suggests that the molecular orbitals responsible for the expression of antiplasmid and carcinogenic effects might be basically different.

Acridines↗

PubMedDate not supplied

Immunomodulation activity of phenothiazines, benzo[a]phenothiazines and benz[c]acridines.

Some non-differentiation-induction benzo[a]phenothiazines and mutagenic benz[c]acridines more potently inhibited the mitogen-induced blast transformation of human-peripheral blood lymphocytes than differentiation-induction and non-mutagenic counterparts and phenothiazines. Differential absorption spectrophotometry revealed tight complex formation between these drugs and bacterial endotoxin or mitogens. All of these compounds only slightly affected antibody dependent cellular cytotoxicity and natural killer cell activity, but significantly inhibited the endotoxin-or heat-killed Staphylococcus aureus induced tumor necrosis factor production by human mononuclear cells. Pretreatment of mice with these drugs protected them from lethal E. coli infection. Quantumchemical analysis suggests a correlation between the biological activity of these compounds and some molecular orbital parameters such as the charge at C7, and the ratio of polar/total surface areas.

Acridines↗

PubMedDate not supplied

Effects of two benzo[a]phenothiazines on multi-drug resistance (mdr) and tumor antigen expression.

Two benzo[a]phenothiazines 5H-benzo[a]phenothiazin-5-one (1), and its derivative 6-methyl-5H-benzo[a]phenothiazin-5-one (2) inhibited the proliferation of human and mouse tumor cell lines. The multi-drug resistant (mdr) subline was more sensitive than its parent cell line to 5H-benzo[a]phenothiazin-5-one (1), 6-methyl-5H-benzo[a]phenothiazin-5-one (2) was equally antiproliferative against the three cell lines tested. Rhodamine 123 efflux of mdr cells was more efficiently inhibited by 5H-benzo[a]phenothiazin-5-one (1) than by 6-methyl-5H-benzo[a]phenothiazin-5-one (2). The exposure of adenovirus infected cells to 5H-benzo[a]phenothiazin-5-one (1) resulted in a reduction of tumor-antigen expression, whereas 6-methyl-5H-benzo[a]phenothiazin-5-one (2) enhanced the T-antigen expression.

Animals↗

PubMedDate not supplied

Effect of chlorpromazine and benzo[a]phenothiazines on heterotrophic auxin requiring and autotrophic auxin non-requiring tobacco tissue cultures.

Chlorpromazine and four benzo[a]phenothiazines were tested on the growth and auxin level of auxin requiring heterotrophic and auxin non-requiring autotrophic tobacco tissue cultures originating from transgenic plants. The auxin content was followed by the expression of GUS reporter gene connected with auxin inducible mass promoter. The benzo[a]phenothiazines had a higher antiproliferative effect than chlorpromazine. The exogenous auxin non-requiring autotrophic callus was more sensitive than the auxin requiring heterotrophic callus (Based on the low GUS activity). The reduced growth of auxin autotrophic tissues may be due to the low endogenous auxin content.

Chlorpromazine↗

PubMedDate not supplied

Induction of DNA fragmentation in human myelogenous leukaemic cell lines by phenothiazine-related compounds.

A series of phenothiazine, benzo[a]phenothiazine and benz[c]acridine derivatives were compared for their ability to induce nucleosome-sized DNA fragmentation (a biochemical hallmark of apoptosis), using agarose gel electrophoresis and a fluorescence activated cell sorter. Significant DNA fragmentation-inducing activity was detected in 12H-benzo[a]phenothiazine, 5-oxo-5H-benzo[a]phenothiazine and 9-methyl-12H-benzo[a]phenothiazine, which induced the monocytic differentiation of human myelogenous leukaemic cell lines. On the other hand, an other three benzo[a]phenothiazines, six 10-[n-(phthalimido)alkyl]-2-substituted-10H-phenothiazines, six 1-(2-chloroethyl)-3-(2-substituted-10H-phenothiazin-10-yl)alkyl-1- ureas, and twelve benz[c]acridines showed little or no DNA fragmentation-inducing activity. Active benzo[a]phenothiazines induced DNA fragmentation in four human myelogenous leukaemic cell lines (HL-60, ML-1, U-937, THP-1), but not in human T-cell leukaemic MOLT-4 and erythroleukaemic K-562 cell lines, which were also resistant to other apoptosis-inducing agents. Ca2+-depletion from the culture medium did not significantly affect their DNA fragmentation-inducing activity. The differentiation and apoptosis-inducing activity of benzo[a]phenothiazines have an important role for their medicinal efficacy.

Acridines↗

PubMedDate not supplied

Relationship between resonance energy per pi-electron and carcinogenicity in arenes.

The resonance energy per pi-electron of various arenes was calculated using Aihara's TRE theory. There seemed to be a correlation between the resonance energy volume per pi-electron of the cation species (lacking a carbon atom) with the highest approximate superdelocalizability (Sr'(E)) from the parent skeleton and carcinogenicity, i.e. the induction of cancer by arenes (three-ring, four-ring, five-ring, six-ring and seven-ring) seems to be dependent on the resonance energy per pi-electron in they contain).

Carcinogens↗

PubMedDate not supplied

Immunomodulating activities on cellular cytotoxicity and the blast transformation of human lymphocytes by 10-[n-(phthalimido)alkyl-2-substituted-10H-phenothiazines and 1-(2-chloroethyl)-3-(2-substituted-10 H-phenothiazin-10-yl)alkyl-1-ureas.

Phenothiazines, 10-[n-(phthalimido)alkyl-2-substituted-10H- phenothiazines, and 1-(2-chloroethyl)-3-(2-substituted-10H-phenothiazin-10-yl)alkyl-1- ureas were investigated for their effects on antibody-dependent cellular cytotoxicity (ADCC), natural killer (NK) cells and the blast transformation of human peripheral blood mononuclear cells. All of the compounds dose-dependently suppressed mitogen-stimulated T cell proliferation. In contrast, a strong enhancing effect on NK cell activity was detected mostly in the case of 1-(2-choroethyl)-3-(2-substituted-10H-phenothiazin-10-yl)alk yl-1-ureas and their related compounds. The stimulating effect directly influenced the NK cells and was demonstrated at all tested concentrations.

Adjuvants, Immunologic↗

PubMedDate not supplied

Antitumor activity of phenothiazine-related compounds.

One of the biggest challenges in health care is the fight against tumors. Some phenothiazines have antitumor activity on HEp-2 tumor cells. In this study, we tested the antitumor effects of three series such as 10-nonsubstituted phenothiazines, 10-[n-(phthalimido)alkyl]-2-substituted-10H-phenothiazines and 1-(chloroethyl)-3-(2-substituted-10H-phenothiazines-10-yl)alkyl-1-ureas with H, Cl and CF3 substitution at position C2. The TCID50 of phenothiazines was affected by the H, Cl and CF3 at C2. Trifluoromethyl derivative of phenothiazine showed potent (R = CF3, TCID50 = 4.7 micrograms) activity, whereas the chlorine derivative of phenothiazine (R = Cl, TCID50 = 62.5 micrograms) had a relatively weak effect. In the group of 10-[n-(phthalimido)alkyl]-2-substituted-10H-phenothiazines, 10-[3-(phthalimido)propyl]-10H-phenothiazine (R = H, n = 3, TCID50 = 11.5 micrograms), 10-[4-(phthalimido)butyl]-10H-phenothiazine (R = H, n = 4, TCID50 = 7.8 micrograms) and 10-[3-(phthalimido)propyl]-2-trifluoromethyl-10H- phenothiazine (R = CF3, n = 3, TCID50 = 11.5 micrograms) was very effective. On the other hand, TCID50 of 10-[3-(phthalimido)propyl]-2-chloro-10H-phenothiazine (R = Cl, n = 3, TCID50 = 75.0 micrograms), 10-[4-(phthalimido)butyl]-2-chloro-10H-phenothiazine (R = Cl, n = 4, TCID50 = 31.3 micrograms) and 10-[4-(phthalimido)butyl]-2-trifluoromethyl-10H-phenothiazine (R = CF3, n = 4, TCID50 = 50.0 micrograms) were about 4-8 times less effective than 10-[4-(phthalimido)butyl]-10H-phenothiazine (R = H, n = 4, TCID50 = 7.8 micrograms). Among six 1-(chloroethyl)-3- (2-substituted-10H-phenothiazin-10-yl)alkyl-1-ureas, two chlorine compounds such as 1-(2-chloroethyl)-3-(2-chloro-10H-phenothiazin-10-yl)propyl-1-urea (R = Cl, n = 3, TCID50 = 6.3 micrograms), 1-(2-chloroethyl)-3-(2-chloro-10H-phenothiazin-10-yl) butyl-1-urea (R = Cl, n = 4, TCID50 = 7.8 micrograms), and 1-(2-chloroethyl)-3-(2-trifluoromethyl-10H-phenothiazin-10-yl)buty l-1-ur ea (R = CF3, n = 4, TCID50 = 7.8 micrograms) were significantly active. Tests showed that the substitution at 2C position apparently affected the anti-HEp-2 tumor cell activity; that the length of the aliphatic side chain at 10N contributes to the anti-tumor activity; and that the TCID50 values of the derivatives with butylene group (-C4H8-) were lower than those with propylene group (-C3H6-) except 10-[4-(phthalimido) butyl]-2-trifuoromethyl-10H-phenothiazine and 1-(2-chloroethyl)-3-(2-chloro-10H-pheno-thiazin-10-yl) butyl-1-urea.

Antineoplastic Agents↗

PubMedDate not supplied

Effect of phenothiazines, benzo[a] phenothiazines, benz[c]acridines and Pentaglobin on endotoxin.

The endotoxin neutralizing effects of several phenothiazines, benzophenothiazines and Pentaglobin (control) were investigated by spectrophotometry, tumor necrosis factor (TNF) induction and the conventional Limulus test. In animal experiments, some beneficial effects of complex forming compounds were found, however, the compounds could not completely inactivate the biological effect of endotoxin in the Limulus test. The complex formation between endotoxin and the compounds were revealed in spectrophotometry. The TNF inducing effect of compound-endotoxin complexes was markedly reduced by some phenothiazines and benzo[a]phenothiazines in leukocytes. Benz[c]acridines and Pentaglobin could not neutralize completely the TNF induction of E. coli endotoxin. The recent findings indicate that multifocal effects of phenothiazines and benzophenothiazines can be responsible for anti-endotoxin action in vivo. Hypotensive action in experimental animals was reduced by some phenothiazines in some preliminary experiments.

Acridines↗

PubMedDate not supplied

Synthesis and antitumor activity of 1-[2-(chloroethyl)-3-(2-substituted-10H-phenothiazin-10-yl)alkyl- 1-urea s as potent anticancer agents.

10-[N-(Phthalimido)alkyl]-2-substituted-10H-phenothiazines and 1-(2-chloroethyl)-3-(2-substituted-10H-phenothiazin-10-yl)alkyl-1- ureas were synthesized and found to have antiproliferative effects on human HEp-2 and L5178Y cell cultures. The multi-drug resistant subline of mouse lymphoma was sensitive to the reversal effects of some 10-[N-(phthalimido)alkyl]-2-substituted-10H-phenothiazines, while 1-(2-chloro-ethyl)-3-(2-substituted-10H-phenothiazin-10-yl)alkyl-1 -ureas were less effective but had a similar degree of antiproliferative effect on both cell lines.

Animals↗

PubMedDate not supplied

Correlations between topological resonance energy of methyl-substituted benz[c]acridines, benzo[a]phenothiazines and chrysenes, and their carcinogenic or antitumor activities.

In order to clarify the effects of methyl substitution on the carcinogenic activity, each resonance energy (RE) of benz[c]acridines, benzo[a]phenothiazines, chrysene, and their methyl derivatives was calculated by Aihara's TRE theory. Some correlations seem to exist between the values of resonance energy per pi-electron for the cationic species-with the lack of the atom having the highest approximate superdelocalizability (Sr'(E)) from their parents skeleton-and carcinogenic activity.

Acridines↗

PubMedDate not supplied

Diverse mutagenicity of methylbenz[c]acridines in the direct Ames' Salmonella mutagenicity assay.

The mutagenicity of eleven methylbenz[c]acridines (methyl-B[c]ACRs) was examined by the direct Ames' Salmonella mutagenicity assay on the standard tester strains of TA97a, TA98, TA100 and TA102, each of which is specific to a certain type of mutation. The Benz[c]acridines (B[c]ACRs) studied in this investigation were substituted with one to three methyl group(s) at the 5, 7, 8, 9, 10 and 11 position(s) of B[c]ACR. A certain degree of mutagenic activity was observed by all methyl-B[c]ACRs on at least one of the tester strains, indicating that even non-carcinogenic methyl-B[c]ACRs showed mutagenicity in the assay. Meanwhile, 7,10-dimethyl-B[c]ACR and 7,9,10-trimethyl-B[c]ACR significantly increased the number of back-mutant colonies. However, monomethyl-B[c]ACRs, 7-methyl-B[c]ACR and 10-methyl-B[c]ACR did not increase back-mutation except for TA102 and TA100, respectively. The induction of 7-methyl substituent on B[c]ACR appears to play a key role in frameshift (+1 and -1), base-pair substitution, and single base substitution mutation of the strains in the presence of additional methyl substituent(s) at C-9 and/or C-10 position(s) of D ring of B[c]ACR.

Acridines↗

PubMedDate not supplied

Relationship between tumor (T) antigen expression and substituent effects on benzo [a] phenothiazines.

Human adenovirus, oncogene-type 12 infected HEp-2 cells were exposed to six benzo[a]phenothiazines. 5-Oxo-5H-benzo[a]phenothiazine (4) and 6-hydroxy-5-oxo-5H-benzo[a]phenothiazine (5) were moderately toxic. 9-Methyl-12H-benzo[a]phenothiazine (2), 10-methyl-12H-benzo[a]phenothiazine (3), 6-methyl-5-oxo-5H-benzo[a]phenothiazine (6), and 12H-benzo[a]phenothiazine (1) were not toxic in the system tested. 6-Methyl-5-oxo-5H-benzo[a]phenothiazine (6) enhanced the expression of viral oncogene product (tumor antigen) in the adenovirus infected cells. 5-Oxo-5H-benzo[a]phenothiazine (4) and 6-hydroxy-5-oxo-5H-benzo[a]phenothiazine (5) reduced this effect. 6-Methyl-5-oxo-5H-benzo[a]phenothiazine (6), with hyperconjugation due to the methyl group, increased the T antigen activity at higher dose concentrations, whereas 6-hydroxy-5-oxo-5H-benzo[a]phenothiazine (5) with a hydroxy substituent had the opposite effect on T antigen expression. The methyl substitution at positions C9 or C10 increased the T antigen expression of adenovirus infected cells.

Antigens, Neoplasm↗

PubMedDate not supplied

Antimutagenicity of benzo[a]phenothiazines in chemically induced mutagenesis.

Antipsychotic phenothiazines are known to have antimutagenic activities. The antimutagenicity of seven Benzo[a]phenothiazines was screened against Salmonella typhimurium strain TA98 treated with 4-nitro-o-phenylenediamine (4-NPD) which is a specific mutagen to this strain, and was compared to the antimutagenic activity of chlorpromazine, a 2-chlorphenothiazine derivative which has been shown to be the most effective mutagen inhibitor in the model. Benzo[a]phenothiazines are variously substituted by methyl-, oxo- and/or hydroxyl-substituent(s) at 5, 6, 9 and/or 10 positions(s). 9-Methyl-12H-benzo[a]phenothiazine [3] reduced the 4-NPD induced mutation by 30 percent, being a more potent antimutagenic agent than chlorpromazine. The study of antimutagenicity is of great interest in the development of cancer chemopreventive agents which halt cancer progression in multistage carcinogenesis, where successive mutation sequences are required to evolve into full-fledged metastatic cancer.

Antimutagenic Agents↗

PubMedDate not supplied

Induction of a protective immunity in mice against Escherichia coli by phenothiazines, 10-[n-(phthalimido)alkyl]-2-substituted-10H-phenothiazines and 1-(2-chloroethyl)-3-(2-substituted-10H-phenothiazines-10-yl)alkyl-1 -ureas .

Abilities of five phenothiazines, six 10-[n-(phthalimido)alkyl]-2-substituted-10H-phenothiazines and six 1-(2-chloroethyl)-3-(2-substituted-10H-phenothiazines-10-yl)alkyl-1- ureas to induce anti-Escherichia coli activity in mice were compared. Seventeen compounds tested in this study had no antibacterial effect in direct contact with Escherichia coli using the disk diffusion method except chlorpromazine (4) with low growth inhibitory action. The pretreatment of mice with several phenothiazines, 10-[n-(phthalimido)alkyl]-2-substituted-10H-phenothiazines or 1-(2-chloroethyl)-3-(2-substituted-10H-phenothiazines-10-yl)alkyl-1- ureas protected the animals from lethal infection of Escherichia coli to various extents. On the basis of these experiments, we assume that the protective effect against Escherichia coli infection might be due to the immunopotentiation or macrophage inducing activity by the compounds, or inactivation of lymphokines induced by the bacteria. Since the infection preventing effect of the tested phenothiazines depends on the chemical structures, the specificity of the biological process can be assumed.

Animals↗

PubMedDate not supplied

Antimutagenicity of benzo[a]phenothiazines in chemically induced mutagenesis.

The antimutagenicity of seven benzo[a]phenothiazines was screened against Salmonella typhimurium strain TA98 treated with 4-nitro-o-phenylenediamine which is a specific mutagen to the strain, and the results were compared to the antimutagenic activity of chlorpromazine (8), one of the 2-chlorophenothiazine derivatives-which have been shown to be the most effective mutagen inhibitors. Benzo[a]phenothiazines with methyl, oxo or hydroxyl substituent(s) at position 5, 6, 9 or 10 were used in the screening tests. 6-Hydroxy-5-oxo-5H-benzo[a]phenothiazine (6) reduced the induced mutation by 27%, being a more potent antimutagenic agent than chlorpromazine (8). The study of antimutagenicity is of great interest for the development of cancer chemopreventive agents which stop cancer progression in multistage carcinogenesis in which successive mutation sequences are required for a progression into full-fledged metastatic cancer.

Antimutagenic Agents↗

PubMedDate not supplied

Relationship between resonance energy and carcinogenicity of azaarenes.

Resonance energy per pi-electron (REPE) of azaarenes were calculated by Aihara's theory of resonance energy (TRE). Consequently, it was shown that the REPE values for the cationic species not having the carbon, or nitrogen atom with the highest approximate superdelocalizability (Sr'(E)) in the parent skeleton were more unstable than those of their parent skeleton. Some correlations seem to exist between the REPE values for the cationic species not having the atom with the highest value of (Sr'(E)) in parent skeleton and carcinogenic activity. Other types of correlations can be assumed in the case of carbazoles 7H-benzo[g]pyrido[2,3-a]carbazole (14), 13H-dibenzo[a]pyrido[3,2-i]carbazole (17), and 7H-benzo[c]pyrido[2,3-g]carbazole (20) although there are some exceptions, i.e., 7H-benzo[g]pyrido[3,2-a]carbazole (15) and 7H-dibenzo[c,g]-carbazole (18). The bond-order affected carcinogenicity induction in some ways as well.

Acridines↗

PubMedDate not supplied

Influence of benzo[a]phenothiazines on the element content of two tobacco tissue cultures differing in hormone requirement.

Cell proliferation and tumor formation are closely connected with hormone metabolism. We report the effect of four benzo[a]phenothiazines (12H-benzo[a]phenothiazine (1), 5-oxo-5H-benzo[a]phenothiazine (2), 10-methyl-12H-benzo[a]phenothiazine (3), and 6-hydroxy-5-oxo-5H-benzo[a]phenothiazine (4) on the growth and changes in the element compositions (Ca, Cl, Cu, I, K, Mg, Mn and Na) of auxin autotrophic and heterotrophic tobacco tissue cultures. The concentration levels of these ions were followed by means of reactor neutron activation analysis.

2,4-Dichlorophenoxyacetic Acid↗