| Fusarium toxins are distributed extensivelly in nature, which are the most dangerous contaminations to food and have very serious danger to human health and stockbreeding. Butenolide (BUT) is a kind of Fusarium toxin extracted from F. tricinctum NRRL3249 , Fusarium nivale , Fusarium equseti , Fusarium sporotrichiodes and Fusarium poae,etc. The common name of this toxin is butenolide (4- Acetamido-4-hydroxy-2-butenoicacid acid . -lactone). It was believed that fescue foot was caused by BUT. However, the mechanism of BUT toxicity is unclear and there are no reports about BUT poisonning in mankind at present yet. In this dissertation, we carried experiments to study the toxic effect of BUT and its toxicity mechanism in rats and chicken embryos both in vivo and in vitro. The effect of lipid peroxidation induced by BUT and the protecting function of selenium and other antioxidants were observed. The present study offered the basis for expound relation of Fusarium toxins and local Keshan disease and Kaschin-Beck disease finally. This research is divided into three parts as follow.Part 1: Pathological characteristics in visceras caused by BUTWe carried on acute toxic and subacute toxic experiment in rats to observe the biochemical and pathological changes in rat visceras after poisoned by BUT.The acute toxic experimental results in rats indicated that BUT can cause a lot of damaging pathological changes in visceras within short time. The changes included the vacuole denaturalization in liver and kidney cells, the lung bleeding and debaucling. When the rats were poisonned after 12h and 24h, the pathologicalchanges lightened to some extent instead. Changes of visceras were most obvious in heart, liver and spleen of which was poisonned after 6h.The results from subacute toxic experiment in rats (treated with BUT for 50 days) indicated that ALP and CREA in the BUT group is obviously higher than that of the control group, ALB , BUN , TG , TCHOL, LDH and GLU of the BUT group is obviously lower than that of the control group.The results showed that the acute poisoning effect in rats caused by BUT is rapidly. The toxin can not only exert a serious influence to liver function and kidney function, but also caused respiratory system damages, which proved that this toxicity can cause comprehensive damages.Part 2: lipid peroxidation effect caused by BUTIn order to confirm that BUT can cause lipid peroxidation, we have observed biochemical changes induced by BUT in rat visceras. We injected BUT at 10 , 50 , 100 . g for each egg to chicken embryo hatched for 11 days, killed and examined the biochemical indexs of heart, liver and kidneys after continuing hatching for 8 days. The results indicated that the content of MDA in heart, liver and kidneys rose to some extent, in contrast, the content of - SH, GSH-Px and NO reduced obviously in dosage dependent manner. The results suggest that BUT was able to induce lipid peroxidation, cause -SH and enzyme lost consequently reduced the anti-oxidant ability of the organism.Part 3: Selenium and other antioxidants antagonized to lipid peroxidation caused by BUTTo probe into antagonizing of antioxidant to lipid peroxidation which induced by BUT, and look for methodes to prevent the lipid peroxidation cauced by BUT, we used selenium compound and other antioxidants such as GSH, VitC, VitE, and SOD etc. with means as stated in second part (surveyed biochemical indexs) to observed the influence of antioxidants to lipid peroxidation caused by BUT. So we can judgethe possible ways of lipid peroxidation and relations between BUT and organism damages.We injected 100u.g BUT and 5 u.g antioxidant to chicken embryo hatched for 11 days, other operations were the same as in the second part. Results from experiment in chicken embryo indicated antioxidants can affect the changes of MDA caused by BUT in heart and liver except in kidney. In vitro, GSH, VitC and VitE can obviously influence biochemical changes which caused by BUT, but the selenium and SOD had not effect.Briefly, the profe...
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