Protective effect of capsaicin against methyl methanesulphonate induced toxicity in the third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg / 中国天然药物

Capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide) is the main component in hot peppers, including red chili peppers, jalapenos, and habanero, belonging to the genus Capsicum. Capsaicin is a potent antioxidant that interferes with free radical activities. In the present study, the possible protective effect of capsaicin was studied against methyl methanesulphonate (MMS) induced toxicity in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg. The third instar was allowed to feed on the diet having different doses of capsaicin and MMS separately and in combination. The results suggested that the exposure of third instar larvae to the diet having MMS alone showed significant hsp70 expression as well as tissue DNA and oxidative damage, whereas the larvae feed on the diet having MMS and capsaicin showed a decrease in the toxic effects for 48-h of exposure. In conclusion, capsaicin showed a dose-dependent decrease in the toxic effects induced by MMS in the third instar larvae of transgenic Drosophila melanogaster.

Inducible protective processes in animal systems XIV: Cytogenetic adaptive response induced by EMS or MMS in bone marrow cells of diabetic Mouse

Background: Adaptive response has been well studied by employing physical and chemical agents in normal test systems, whereas in diseased conditions very little data are available

Aim of the study: To know the presence or absence of adaptive response in diseased condition, alkylating agents such as EMS or MMS have been employed in diabetic mouse

Material and methods: To induce diabetes, mice were injected with 180 mg/kg body weight of Stz. Diabetic mice were treated with conditioning [100 mg/kg body weight of EMS or 40 mg/kg body weight of MMS], challenging [300 mg/kg body weight of EMS or 160 mg/kg body weight of MMS] and combined doses of EMS or MMS with 8 h time lag. Parallelly controls were maintained. Mice were sacrificed at 24 or 48 or 72 h RTs. Bone marrow was extracted and slides were prepared by a routine air dry technique by Evans et al. [1964] to analyze the chromosomal aberrations

Results: The results show that both the alkylating agents induced exclusively chromatid type of aberrations in both diabetic and non diabetic mice, but it is to be underlined that MMS is a more potent inducer of aberrations than EMS. Eventhough, combined treatment of EMS or MMS induced significantly less chromosomal breaks compared to challenging treatment [p< 0.05] in diabetic mice, EMS induced 40% reduction of breaks, compared to 51.74% by MMS at 24 h RT. This is true to other tested RTs

Conclusion:[1] Methylating agents are a more effective inducer of adaptive response than ethylating agents in diabetic mouse. [2] Further, it is interesting to note that the percentage reduction of chromosomal breaks in diabetics is comparatively much less than in non diabetic mouse, inferring that there is variation in adaptive response between diseased and non diseased condition

Medication adherence and quality of life among the elderly with diabetic retinopathy / Adesão medicamentosa e qualidade de vida em idosos com retinopatia diabética / Adhesión a la medicación y calidad de vida en ancianos con retinopatía diabética

METHOD: one hundred (n=100) elderly outpatients with diabetic retinopathy taking antihypertensives and/or oral antidiabetics/insulin were interviewed. Adherence was evaluated by the adherence proportion and its association with the care taken in administrating medications and by the Morisky Scale. The National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) was used to evaluate HRQoL. RESULTS: most (58%) reported the use of 80% or more of the prescribed dose and care in utilizing the medication. The item "stopping the drug when experiencing an adverse event", from the Morisky Scale, explained 12.8% and 13.5% of the variability of adherence proportion to antihypertensives and oral antidiabetics/insulin, respectively. CONCLUSION: there was better HRQoL in the Color Vision, Driving and Social Functioning domains of the NEI VFQ-25. Individuals with lower scores on the NEI VFQ-25 and higher scores on the Morisky Scale presented greater chance to be nonadherent to the pharmacological treatment of diabetes and hypertension. .

OBJETIVO: investigar os fatores relacionados à adesão medicamentosa e sua relação com a qualidade de vida relacionada à saúde em idosos com retinopatia diabética. MÉTODO: foram entrevistados 100 idosos, em acompanhamento ambulatorial, em uso de anti-hipertensivos e/ou antidiabéticos orais/insulina. A adesão foi avaliada pela proporção de adesão e sua associação com os cuidados no uso dos medicamentos e pela Escala de Morisky. O National Eye Institute Visual Funcioning Questionnaire foi utilizado para avaliar a qualidade de vida relacionada à saúde. RESULTADOS: A maioria (58%) relatou o uso de 80% ou mais das doses prescritas e os cuidados na tomada dos medicamentos. O item "interromper o uso dos medicamentos por se sentir pior", da Escala de Morisky, explicou 12,8 e 13,5% da variabilidade da proporção de adesão aos anti-hipertensivos e aos antidiabéticos orais/insulina, respectivamente. CONCLUSÃO: observou-se melhor qualidade de vida relacionada à saúde nos domínios visão de cores, dirigir automóvel e apectos sociais do National Eye Institute Visual Funcioning Questionnaire. Indivíduos com menor pontuação na National Eye Institute Visual Funcioning Questionnaire e maiores escores na Escala de Morisky apresentaram maiores chances de serem não aderentes aos medicamentos do diabetes e da hipertensão arterial. .

OBJETIVO: investigar los factores relacionados a la adhesión a la medicación y su relación con la Calidad de Vida Relacionada a la Salud (CVRS) de ancianos con retinopatía diabética. MÉTODO: fueron entrevistados cien (n=100) pacientes ancianos de ambulatorio con retinopatía diabética que toman medicamentos antihipertensivos y/o antidiabéticos orales/insulina. La adhesión fue evaluada mediante la proporción de adhesión y su asociación con el cuidado tomado en la administración de medicamentos y mediante la Escala de Morisky. El National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) fue usado para evaluar la CVRS. RESULTADOS: la mayoría (58%) relató el uso de 80% o más de la dosis prescrita y cuidado con el uso de la medicación. El ítem "suspender la droga cuando vivencia un evento adverso", de la Escala de Morisky, explicó 12.8% y 13.5% de la variabilidad en la proporción de adhesión a los antihipertensivos y antidiabéticos orales/insulina, respectivamente. CONCUSIÓN: fue encontrada mejor CVRS en los dominios de Visión Cromática, Dirección y Funcionamiento Social del NEI VFQ-25. Individuos con puntuaciones menores en el NEI VFQ-25 y puntuaciones mayores en la Escala de Morisky revelaron mayor chance de no adhesión al tratamiento farmacológico de la diabetes y hipertensión. .

Análisis fitoquímico de Jatropha dioica y determinación de su efectoantioxidante y quimioprotector sobre el potencial genotóxico deciclofosfamida, daunorrubicina y metilmetanosulfonato evaluadomediante el ensayo cometa / Phytochemical analysis of Jatropha dioica and determination of its antioxidant and chemopreventive effect on the genotoxic potential of cyclophosphamide, daunorubicin and methyl methane-sulfonate evaluated by the comet assay

Dragon ́s blood root (Jatropha dioica) underwent a phytochemical screening showing the presence of flavonoids and terpenes responsible for the antioxidant potential observed in DPPH model for the decoction, aqueous and methanolic extracts. The chemoprotective effect of the root decoction was evaluated in liver, kidney and bone marrow cells of mice using the comet assay. Mutagens were administered via IP: cyclophosphamide (CCF) 50 mg/kg, daunorubicin (DAU) 10 mg/kg, and metyl metanesulfonate (MMS) 40 mg/kg, were co-administered with three doses of decoction 3.72 ml/kg, 10.71 ml/kg, and 21.42 ml/kg orally. Animals were sacrificed at 3, 9, 15 and 21 h after inoculation. The chemoprotective effect decreased DNA breaks at 3 hours in all organs, and longer against CCF and DAU, this effect probably being related to the antioxidant capacity of the decoction.

La raíz de Sangre de Drago (Jatropha dioica) se sometió a un tamizaje fitoquímico destacando la presencia de flavonoides y terpenos, posibles responsables del efecto antioxidante observado en el modelo de DPPH para la decocción, extracto acuoso y metanólico de la raíz. El efecto quimioprotector de la decocción, se evaluó en células hepáticas, renales y de médula ósea de ratón, mediante el ensayo cometa. Los mutágenos administrados vía I.P.: ciclofosfamida (CCF) 50 mg/kg, daunorrubicina (DAU) 10 mg/kg y metilmetanosulfonato (MMS) 40 mg/kg, se co-administraron con tres dosis de decocción 3,72 ml/kg, 10,71 ml/kg y 21,42 ml/kg, vía oral. Los animales fueron sacrificados a las 3, 9, 15 y 21 h posteriores a la aplicación. El efecto quimioprotector disminuyó las rupturas del DNA a las 3 horas en todos los órganos con los tres mutágenos, y permaneció por más tiempo frente a CCF y DAU, dicho efecto está relacionado con la capacidad antioxidante de la decocción.

Clavulanic acid production by the MMS 150 mutant obtained from wild type Streptomyces clavuligerus ATCC 27064

Clavulanic acid (CA) is a powerful inhibitor of the beta-lactamases, enzymes produced by bacteria resistants to penicillin and cefalosporin. This molecule is produced industrially by strains of Streptomyces clavuligerus in complex media which carbon and nitrogen resources are supplied by inexpensive compounds still providing high productivity. The genetic production improvement using physical and chemical mutagenic agents is an important strategy in programs of industrial production development of bioactive metabolites. However, parental strains are susceptible to loss of their original productivity due genetic instability phenomenona. In this work, some S. clavuligerus mutant strains obtained by treatment with UV light and with MMS are compared with the wild type (Streptomyces clavuligerus ATCC 27064). The results indicated that the random mutations originated some strains with different phenotypes, most divergent demonstrated by the mutants strains named AC116, MMS 150 and MMS 54, that exhibited lack of pigmentation in their mature spores. Also, the strain MMS 150 presented a larger production of CA when cultivated in semi-synthetics media. Using other media, the wild type strain obtained a larger CA production. Besides, using the modifed complex media the MMS 150 strain showed changes in its lipolitic activity and a larger production of CA. The studies also allowed finding the best conditions for a lipase activity exhibited by wild type S. clavuligerus and the MMS150 mutant.

Generation and Evaluation of High beta-Glucan Producing Mutant Strains of Sparassis crispa

A chemical mutagenesis technique was employed for development of mutant strains of Sparassis crispa targeting the shortened cultivation time and the high beta-glucan content. The homogenized mycelial fragments of S. crispa IUM4010 strain were treated with 0.2 vol% methyl methanesulfonate, an alkylating agent, yielding 199 mutant strains. Subsequent screening in terms of growth and beta-glucan content yielded two mutant strains, B4 and S7. Both mutants exhibited a significant increase in beta-glucan productivity by producing 0.254 and 0.236 mg soluble beta-glucan/mg dry cell weight for the B4 and S7 strains, respectively, whereas the wild type strain produced 0.102 mg soluble beta-glucan/mg dry cell weight. The results demonstrate the usefulness of chemical mutagenesis for generation of mutant mushroom strains.

Effects of overexpression of human pol-beta on cellular response to DNA damage / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the biological effects of overexpression of the human DNA polymerase (pol-beta) on cellular response to DNA damage.</p><p><b>METHODS</b>The cell strain HLFbeta from the stable overexpression of the human pol-beta was contaminated with methyl methanesulfonate (MMS) for investigating the effects of the pol-beta on the cellular responses to DNA damage on the aspects such as the DNA damage, the cell cycle and the induced mutation rate.</p><p><b>RESULTS</b>The cell HLFbeta from the stable overexpression of the human pol-beta was obtained through the screening. The cellular response to DNA damage of HLFbeta induced by the MMS in the intermediate and high dosage group (ranging from 0.5 to 0.8 mmol/L) was significantly lower than that in the control group. The analysis for the cell cycle distribution showed that both the two types of cells contaminated by MMS had retardation at G(2) phase. In the HLFbeta group, the cells had the obvious G(2) phase retardation and 49.0% of the cells were retarded at G(1) phase as well when the MMS was increased to 0.5 mmol/L while in the control, only 20.1% of the cells were retarded at the G(1) phase when the same dosage of MMS was administered. Moreover, the MMS-induced mutagenesis in HLFbeta was increased from 4.5 x 10(-6) to 8.2 x 10(-6), significantly higher than that in the control group (P < 0.05).</p><p><b>CONCLUSION</b>High Pol-beta level decreases cellular DNA damage induced by MMS. Nevertheless, the overexpression of Pol-beta can also increase error-prone DNA synthesis during DNA repair process.</p>

Antigenotoxic effect of allicin against methyl methanesulphonate induced genotoxic damage.

Allicin, one of the sulfur compounds especially thiosulphonates of garlic (Allium sativum), possesses antioxidant and thioldisulphide exchange activity and is also shown to cause a variety of actions potentially useful for human health. In this investigation we determined its antigenotoxic potential using chromosomal aberrations (CAs) and sister chromatid exchanges (SCEs) induced by methyl methanesulphonate (MMS) as genotoxic end points both in the presence as well as absence of rat liver microsomal activation system (S9 mix) in cultured human lymphocytes. We tested the effect of 5, 10 and 20 microM of allicin on the damage exerted by 60 microM of MMS. The levels of CAs and SCEs were lowered suggesting an antigenotoxic role of allicin against genotoxic damage both in the presence as well as absence of metabolic activation.

Influence of 1.8 GHz microwave on DNA damage induced by 4 chemical mutagens / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To observe the influence of 1.8 GHz microwave (MW) specific absorption rate (SAR, 3 W/kg) on human lymphocytes DNA damage induced by 4 chemical mutagens [mitomycin C (MMC), bleomycin (BLM), methyl methanesulfonate (MMS), and 4-nitroquinoline 1-oxide (4NQO)].</p><p><b>METHODS</b>Comet assay in vitro was used to detect human lymphocyte DNA damage induced by 1.8 GHz MW, 4 chemical mutagens, and MW plus 4 chemicals 0 h and 21 h respectively after exposure. The time exposed to MW or mutagens was 2 h or 3 h respectively. The results were showed by tail length (TL) and tail moment (TM).</p><p><b>RESULTS</b>The difference of DNA damage between MW group and control group was not statistically significant (P > 0.05). DNA damages in MW plus MMC groups and MW plus 4NQO groups were significantly greater than those in the corresponding concentrations of MMC groups and 4NQO groups (P < 0.01 or P < 0.05). However, MW did not enhance DNA damage induced by MMS and BLM (P > 0.05).</p><p><b>CONCLUSION</b>Exposure to 1.8 GHz (SAR, 3 W/kg) microwave may not induce human lymphocyte DNA damage, but could enhance DNA damage induced by MMC and 4NQO.</p>

Antigenotoxic effect of allicin against SCEs induced by methyl methanesulphonate in cultured mammalian cells.

Allicin, one of the sulphur compounds of garlic (Allium sativum), possesses antioxidant and thiol disulphide exchange activity and is also shown to cause a variety of activities potentially useful for human health. In this investigation, the effect of 1,5,10 and 20 microM of allicin was determined for inhibiting the rate of SCE induced by 60 microM of MMS. Cultured human lymphocytes from two female donors were used for the experiment. The levels of SCEs were lowered by allicin suggesting its antigenotoxic activity in mammalian cells in vitro.

Effects of 2,450 MHz microwave on DNA damage induced by three chemical mutagens in vitro / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the combined damage-effects of low-intensity 2,450 MHz microwave (MW) with three chemical mutagens on human lymphocyte DNA.</p><p><b>METHODS</b>DNA damage of lymphocytes exposed to microwave and(or) with chemical mutagens were observed at different incubation time (0 h or 21 h) with comet assay in vitro. Three combination-exposure ways of MW with chemicals were used: MW irradiation before chemical exposures, simultaneously exposed to MW and chemicals and MW irradiation after chemical exposures. The three chemical mutagens were mitomycin C (MMC, DNA crosslinker), bleomycin (BLM, radiometric agent), methyl methanesulfonate (MMS, alkylating agent). The exposure time of MW and chemical mutagens were 2 h and 3 h respectively.</p><p><b>RESULTS</b>The differences of comet tail length between MW group and control group were not significant when lymphocytes were incubated for 0 h or 21 h (P > 0.05). However, when lymphocytes were incubated for 21 h with 30.00 micro mol/L of MMC, the comet tail lengths of MW + MMC group, MW-MMC group and MMC + MW group were (18.00 +/- 5.96), (21.79 +/- 11.47) and (22.32 +/- 8.10) micro m respectively; while with 3.00 micro mol/L of MMC, the comet tail lengths were (8.99 +/- 3.75), (12.40 +/- 5.35) and (14.00 +/- 5.38) micro m respectively, which were significantly higher than those of corresponding MMC groups [(9.42 +/- 3.34) and (6.50 +/- 2.89) micro m, P < 0.01 or P < 0.05]. The DNA damage of MW plus BLM groups and MW plus MMS groups were not significantly different from the corresponding BLM and MMS groups (P < 0.05).</p><p><b>CONCLUSION</b>2 450 MHz MW (5 mW/cm(2)) did not induce DNA damage directly, but could enhance the DNA damage effects induced by MMC. The synergistic effects of 2 450 MHz MW with BLM and MMS were not obvious.</p>

Adaptive response to low dose of EMS or MMS in human peripheral blood lymphocytes.

Human peripheral blood lymphocytes stimulated in vitro for 6 hr were exposed to a low (conditioning) dose of ethyl methanesulfonate (EMS; 1.5 x 10(-4) M) or methyl methanesulfonate (MMS; 1.5 x 10(-5) M). After 6 hr, the cells were treated with a high (challenging) concentration of the same agent (1.5 x 10(-3) M EMS or 1.5 x 10(-4) M MMS). The cells that received both conditioning and challenging doses became less sensitive to the induction of sister chromatid exchanges (SCEs) than those which did not receive the pretreatment with EMS or MMS. They responded with lower frequencies of SCEs. This suggests that conditioning dose of EMS or MMS has offered the lymphocytes to have decreased SCEs. This led to the realization that pre-exposure of lymphocytes to low dose can cause the induction of repair activity. This is a clear indication of the existence of adaptive response induced by alkylating agents whether it is ethylating or methylating in human lymphocytes in vitro.

Identification of Differentially Expressed Genes Using RNA Fingerprinting in Cell after DNA Damage

RNA fingerprinting using on arbitrary primed polymerase chain reaction (RAP-PCR) was carried out to identify differentially expressed genes in HL-60 cell after treatment of methylmethane sulfonate (MMS). Twenty differentially expressed PCR products were cloned and analyzed. We have successfully obtained eight partial cDNA sequences by TA cloning method. Among these, six cDNAs were up-regulated and two cDNAs were down-regulated after the MMS treatment. Of these six up-regulated cDNAs, 3 cDNAs were equivalent to known genes in the GenBank/EMBL databases with 98~100% homology searched by BLAST program: genomic DNA fragment containing CpGg island (clone 26h8), Human Rev interacting protein-1 (RIP-1), and human zinc finger protein-4 (HZF4). The sequences of the three remaining cDNA were entirely new genes, but we didn't try to identify a full cDNA sequence. Two clones called KIAA0060 and KIAA0065, were down-regulated in HL-60 cells after the MMS treatment. These findings suggest that the RNA fingerprinting method using RAP-PCR is an effective method which can identify and separate the differentially expressed cDNAs and that the isolated cDNAs might involve in regulation mechanism of apoptosis and/or cell cycle delay, especially a p53-independent pathway, in the cells after DNA damage. But the nature of cDNAs that we have isolated remains to be elucidated.

Inducible protective processes in animal systems: adaptive response to a low dose of methyl methanesulfonate in mouse bone marrow cells.

To investigate the induction of adaptive response (inducible protective processes) in mitotic cells of Swiss albino mouse, a monofunctional alkylating agent methyl methanesulfonate (MMS) was employed. When the animals treated with a low dose of 50 mg/kg body weight were challenged with a subsequent high (challenging) dose of 150 mg/kg body weight, after different time lags (2,5,8 or 10 hr), the yield of chromosomal aberrations in bone marrow cells was found to be significantly reduced compared to the additive effects of both conditioning and challenging doses. It seems, therefore, that the low dose of MMS employed has made the cells less sensitive against further clastogenic effect of challenge dose of MMS. The data clearly suggest that the phenomenon of adaptive response to methylating agents can be encountered in in vivo mammalian cells. Furthermore, it is also observed that ethylating agent EMS is a poor inducer of adaptive response than its corresponding methylating agent MMS in the bone marrow cells of mouse.