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Alcoholism is associated with a higher incidence of smoking. In addition to the stimulatory effects of both ethanol and nicotine on the mesolimbic reward pathway, nicotine's ability to counteract some of the adverse effects of ethanol (e.g. ataxia) may be a powerful incentive for alcohol consumers to increase their tobacco (nicotine) intake. The cerebellum is believed to play an important role in ethanol-induced ataxia. In this study, we sought to test the hypothesis that nicotine would protect against toxic effects of ethanol in primary cultures of cerebellar granule cells. Moreover, it was postulated that the effects of nicotine would be mediated through nicotinic receptors. Primary cultures of cerebellar granule cells were prepared from 20-day embryos obtained from timed-pregnant Sprague Dawley rats. Cells were cultured for 10 days and were then exposed for 3 days to various concentrations of ethanol with and without pretreatment with nicotine and nicotinic antagonists. Cellular toxicity was evaluated by measuring the lactate dehydrogenase level. Administration of ethanol (10-100 mM) resulted in a dose-dependent toxicity. Pretreatment with nicotine 1-20 micro M resulted in a dose-dependent protection against ethanol-induced toxicity. The effects of nicotine were blocked by pretreatment with nicotinic antagonists such as mecamylamine 1-20 micro M, dihydro-beta-erythroidine 1.0 nM-1.0 micro M and methyllycaconitine 5 nM-5 micro M in a dose-dependent manner. Thus, ethanol-induced cytotoxicity in primary cultures of cerebellar granule cells is blocked by pretreatment with nicotine. The effects of nicotine, in turn, may be blocked by nicotinic antagonists, implicating both high and low affinity nicotinic receptors in mediating the actions of nicotine. The exact mechanism of ethanol-induced toxicity and/or neuroprotection through activation of nicotinic receptors in this paradigm remains to be elucidated. The neuroprotective effect of nicotine against ethanol-induced toxicity in cerebellar neurons may be a contributing factor to the high incidence of smoking among alcoholics.

Tumor necrosis factor-alpha (TNF-alpha) production is a critical factor in the pathogenesis of alcoholic liver injury. Both oxidative stress and endotoxin have been implicated in the process of alcohol-induced TNF-alpha production. However, a cause-and-effect relationship between these factors has not been fully defined. The present study was undertaken to determine the mediators of acute alcohol-induced TNF-alpha production using a mouse model of acute alcohol hepatotoxicity. Alcohol administration via gavage at a dose of 6 g/kg to 129/Sv mice induced hepatic TNF-alpha production in Kupffer cells as demonstrated by measuring protein levels, immunohistochemical localization, and mRNA expression. Alcohol intoxication caused liver injury in association with increases in plasma endotoxin and hepatic lipid peroxidation. Treatment with an endotoxin neutralizing protein significantly suppressed alcohol-induced elevation of plasma endotoxin, hepatic lipid peroxidation, and inhibited TNF-alpha production. Treatment with antioxidants, N-ACETYL-L-CYSTEINE, or dimethylsulfoxide, failed to attenuate plasma endotoxin elevation, but significantly inhibited alcohol-induced hepatic lipid peroxidation, TNF-alpha production and steatosis. All treatments prevented alcohol-induced necrotic cell death in the liver. This study thus systemically dissected the relationship among plasma endotoxin elevation, hepatic oxidative stress, and TNF-alpha production following acute alcohol administration, and the results demonstrate that oxidative stress mediates endotoxin-induced hepatic TNF-alpha production in acute alcohol intoxication.

Background: The consumption of significant amounts of alcohol (ethanol, EtOH) may markedly increase serum triglyceride levels. This study describes a significant increase in fasting serum triglyceride (TG) levels in adult male rats whose mothers consumed EtOH. The hypertriglyceridemia occurred although the offspring never directly consumed EtOH and had consumed only rat chow for the preceding 14 months. Furthermore, both male and female adult offspring had an additional, significant increase in TG levels if their mothers consumed EtOH and experienced stress (restraint) during the pregnancy.Methods: Harlan‐derived Sprague Dawley® female rats were dosed during pregnancy with EtOH via a liquid diet, and their offspring were compared with offspring of mothers who were either fed ad libitum or pair‐fed the liquid diet without EtOH. At birth, the offspring of EtOH mothers exhibited no visible abnormalities except reduced weight, and all offspring were surrogate fostered within 48 hr of birth to mothers who had consumed commercial rat chow throughout their pregnancy. After weaning, all offspring consumed only commercial rat chow, and they were examined over the next 14 months for changes in triglyceride homeostasis as a function of maternal alcohol intake.Results: Adult male offspring of mothers that consumed EtOH during their pregnancy had significant increases in fasting serum triglycerides associated with an increase in the very low density lipoprotein serum fraction. Acute administration of insulin to the offspring of all maternal dietary groups resulted in a rapid clearing of the serum triglycerides, and there were no differences in basal or heparin‐releasable lipoprotein lipase activity between any of the progeny. Castration of the male offspring of EtOH‐treated mothers prevented the development of elevated TG levels. Administration of testosterone to littermate female offspring increased circulating TG levels compared with testosterone‐treated offspring of pair‐fed mothers. EtOH‐consuming mothers who also underwent five periods of restraint‐induced stress (approximately 10 min each session) produced offspring whose fasting serum TG levels were higher than those whose mothers consumed EtOH but experienced no restraint or who experienced restraint but no EtOH. Maternal stress significantly reduced lipoprotein lipase activity in some offspring treatment groups, but the changes did not correspond to changes in the serum TG levels of the offspring. That is, maternal restraint‐induced stress was associated with a loss of heparin‐releasable lipoprotein lipase activity by male progeny from pair‐fed and EtOH‐fed mothers and the female offspring of ad libitum‐fed and EtOH‐fed mothers.Conclusions: Although serum triglycerides increased with age in all offspring, the increase was much more pronounced in the progeny of mothers who consumed EtOH during their pregnancy. The hypertriglyceridemia was significantly more pronounced in the male offspring and in female offspring treated with testosterone. Castration of male offspring inhibited the hypertriglyceridemia development, which suggests that male sex hormones may play a role in the development of this condition. Maternal EtOH consumption coupled with maternal restraint‐induced stress significantly increased the level of hypertriglyceridemia in both male and female offspring compared with offspring whose mothers experienced restraint but no EtOH or EtOH with no restraint. If this study models the human condition, the results could represent an unrecognized risk factor in a number of adult disease states hypothesized to be associated with hypertriglyceridemia, such as cardiovascular disease, hypertension, and diabetes.

Abstract In the first side-by-side large-scale trials of these two C4 crops in the U.S. Corn Belt, Miscanthus (Miscanthus × giganteus) was 59% more productive than grain maize (Zea mays). Total productivity is the product of the total solar radiation incident per unit land area and the efficiencies of light interception (ϵ i) and its conversion into aboveground biomass (ϵ ca). Averaged over two growing seasons, ϵ ca did not differ, but ϵ i was 61% higher for Miscanthus, which developed a leaf canopy earlier and maintained it later. The diurnal course of photosynthesis was measured on sunlit and shaded leaves of each species on 26 dates. The daily integral of leaf-level photosynthetic CO2 uptake differed slightly when integrated across two growing seasons but was up to 60% higher in maize in mid-summer. The average leaf area of Miscanthus was double that of maize, with the result that calculated canopy photosynthesis was 44% higher in Miscanthus, corresponding closely to the biomass differences. To determine the basis of differences in mid-season leaf photosynthesis, light and CO2 responses were analyzed to determine in vivo biochemical limitations. Maize had a higher maximum velocity of phosphoenolpyruvate carboxylation, velocity of phosphoenolpyruvate regeneration, light saturated rate of photosynthesis, and higher maximum quantum efficiency of CO2 assimilation. These biochemical differences, however, were more than offset by the larger leaf area and its longer duration in Miscanthus. The results indicate that the full potential of C4 photosynthetic productivity is not achieved by modern temperate maize cultivars.

Background: Most of the studies of alcoholic liver disease use models in which animals undergo involuntary administration of high amounts of ethanol and consume diets that are often high in polyunsaturated fatty acids. The objectives of this study were (1) to evaluate whether cynomolgus monkeys (Macaca fascicularis) drinking ethanol voluntarily and consuming a diet with moderate amounts of lipid would demonstrate any indices of alcoholic liver disease past the fatty liver stage and (2) to determine whether these alterations were accompanied by oxidative stress.Methods: Six adult male and 6 adult female cynomolgus monkeys were allowed to consume ethanol voluntarily for 18 to 19 months. Additional monkeys were maintained on the same consumption protocol, but were not provided with ethanol. During the course of the study, liver biopsy samples were monitored for lipid deposition and inflammation, serum for levels of liver enzymes, and urine for concentrations of the isoprostane (IsoP) metabolite, 2,3‐dinor‐5,6‐dihydro‐15‐F2t‐IsoP, a biomarker for oxidative stress. Liver mitochondria were monitored for respiratory control and liver for concentrations of neutral lipids, adenine nucleotides, esterified F2 isoprostanes, oxidized proteins, 4‐hydroxynonenal (HNE)‐protein adducts, and protein levels of cytochrome P‐450 2E1 and 3A4.Results: Ethanol consumption ranged from 0.9 to 4.05 g/kg/d over the period of the study. Serum levels of aspartate amino transferase were elevated in heavy‐consuming animals compared with those in ethanol‐naïve or moderate drinkers. Many of the ethanol consumers developed fatty liver and most showed loci of inflammation. Both hepatic energy charge and phosphorylation potential were decreased and NADH‐linked respiration was slightly, but significantly depressed in coupled mitochondria as a result of heavy ethanol consumption. The urinary concentrations of 2,3‐dinor‐5,6‐dihydro‐15‐F2t‐IsoP increased as high as 33‐fold over that observed in ethanol‐abstinent animals. Liver cytochrome P‐450 2E1 concentrations increased in ethanol consumers, but there were no ethanol‐elicited increases in hepatic concentrations of the esterified F2 isoprostanes, oxidized proteins, or HNE‐protein adducts.Conclusion: Our studies show that cynomolgus monkeys undergoing voluntary ethanol consumption for 1.5 years exhibit many of the features observed in the early stages of human alcoholic liver disease. Ethanol‐elicited fatty liver, inflammation, and elevated serum aspartate amino transferase were evident with a diet that contained modest amounts of polyunsaturated lipids. The dramatic increases in urinary IsoP demonstrated that the animals were being subjected to significant oxidative stress that correlated with their level of ethanol consumption.

Production of fuels and chemicals through microbial fermentation of plant material is a desirable alternative to petrochemical-based production. Fermentative production of biorenewable fuels and chemicals requires the engineering of biocatalysts that can quickly and efficiently convert sugars to target products at a cost that is competitive with existing petrochemical-based processes. It is also important that biocatalysts be robust to extreme fermentation conditions, biomass-derived inhibitors, and their target products. Traditional metabolic engineering has made great advances in this area, but synthetic biology has contributed and will continue to contribute to this field, particularly with next-generation biofuels. This work reviews the use of metabolic engineering and synthetic biology in biocatalyst engineering for biorenewable fuels and chemicals production, such as ethanol, butanol, acetate, lactate, succinate, alanine, and xylitol. We also examine the existing challenges in this area and discuss strategies for improving biocatalyst tolerance to chemical inhibitors.

ABSTRACT When the yeast Saccharomyces cerevisiae shifts from rapid growth on glucose to slow growth on ethanol, it undergoes profound changes in cellular metabolism, including the destruction of most of the translational machinery. We have examined the effect of this metabolic change, termed the diauxic shift, on the frequency of translational errors. Recoding sites are mRNA sequences that increase the frequency of translational errors, providing a convenient reporter of translational accuracy. We found that the diauxic shift causes no overall change in translational accuracy but does cause a strong reduction in the frequency of one type of programmed error: Ty +1 frameshifting. Genetic data suggest that this effect may be due to changes in the relative amounts of tRNA participating in translation elongation. We discuss possible implications for expression strategies that use recoding.

To determine the relationship among helmet use, alcohol use, and ethnicity in people killed on motorcycles.Retrospective review of all motorcycle fatalities in New Mexico from 1984 through 1988.Office of the Medical Investigator, State of New Mexico.All decedents of motorcycle crashes in New Mexico from 1984 through 1988.Review of all autopsies, medical investigator reports, traffic fatality reports, and toxicological studies on fatally injured motorcyclists.Nine of the helmeted drivers (18%) were legally intoxicated compared with 67 of the nonhelmeted drivers (51%) (chi 2 = 15.7, P less than .0001); 42 of the white nonHispanic decedents (37%), ten of Hispanic decedents (12%), and none of the Native-American decedents were wearing helmets. The head and neck region was the most severely injured body region in 42 of the nonhelmeted cases (84%) and in eight of the helmeted cases (50%) (Fisher's exact test, P less than .02).There is an association between nonuse of helmets and alcohol intoxication in fatally injured motorcyclists in New Mexico. Strategies for preventing motorcycle fatalities should address alcohol abuse and ethnicity in conjunction with helmet use.