Studies On The Liver Immune,brian Analgesic And Reproductive Activity Of Aphantoxin On Male Zebrafish

Eutrophication of water bodies because of natural and human factors has caused some algae to over-produce and caused blooms.Aphantoxin secreted by Aphanizomenon flosquae,the dominant algae species,has attracted people’s attention because of its strong paralysis effect and rapid toxicity.In order to explore the medicinal activity,toxicity mechanism and the influence on the reproductive development of aphantoxin,we used zebrafish as model animal to study the response of zebrafish liver,brain and goand after intraperitoneal injection of low and high doses of aphantoxin and acetic acid(control).Zebrafish were sacrificed at 1,3,6,9,12,and 24 hours respectively after exposed to aphantoxin.Then,zebrafish were dissected immediately,and preserved their liver,brain and gonad properly.Tissue anatomy and transmission electron microscopy were used to study the changes in tissue structure and ultrastructure.Based on this,ELISA and ultraviolet spectrophotometry were used to detect its physiological response.Then q RT-PCR was used to further study the response of m RNA transcription level.The results will reveal the activity,toxicity,and toxicity mechanism of mitogen toxin on zebrafish reproductive function,liver immunity and brain analgesia,and provide important experimental basis for drug development and detoxification countermeasures.The results of this study will reveal the effects of aphantoxin on reproductive function,liver immunity,and brain analgesic in zebrafish,as well as its toxicological mechanisms.It provides an important basic experimental basis for the drug development and detoxification strategies of aphantoxin.The main findings are as follows:1.Aphantoxin or PSPs induced proinflammatory alterations in TNF-α,IL-1β,IL-6,and IL-8,subsequently altered the anti-inflammatory function of IL-10 and TGF-β,and further induced surface morphological alterations due to hyperemia and increased HSI in zebrafish liver.These changes were induced due to altered m RNA expression in zebrafish liver caused by aphantoxin or PSPs.These results show that the immune parameters of hyperemia,HSI,and TNF-α,IL-1β,IL-6,IL-8,IL-10,and TGF-βlevels in the zebrafish liver may be used as important biomarkers to investigate the effects of aphantoxin and blooms in nature.2.The results of the study on the response of the zebrafish brain pain signal to the aphantoxin showed that the toxin can increase the content of SP andβ-EP.The up-regulation of m RNA explains the changes of physiological level.However,physiological level of Glu and His and m RNA expression of m Glu R1 and Hrh1 are inhibited.Decreased m RNA expression of the receptors may be due to the decrease content of Glu and His.This indicates that aphantoxin can suppress pain and excitement conduction by reducing the Glu level,the up-regulated SP andβ-EP exert analgesic effect,and the inhibition of His expression indicates that the toxin does not exert analgesic effect through K~+channels.These studies of analgesic nerve signals are of great significance to reveal how aphantoxin can exert analgesic and paralytic effects,and also provide an important basis for the development of aphantoxin drugs.3.As the result of the response of male zebrafish HPG to the aphantoxin,it was found that when the toxin acts on the brain,Gn RHR and LH are down-regulated,and Gn RH and FSH are slightly up-regulated.The changes of Gn RH and FSH are to maintain the balance of gonadotropins in the hypothalamus and pituitary.Pituitary hormones act on the testis,leading to increased levels of reproductive hormone receptors(FSHR,LHR,AR)and hormone regulatory proteins(ACV-B,St AR).Combining with the results of brain studies,the combination of FSHR and FSH exerts the role of FSH fully.Through further research on steroid hormones and hormone synthetases in the testis,it was found that the decreased transcription expression of CYP17A1 led to a decrease in the synthesis of 17OH-PREG and DHEA,and caused other steroid hormones(PREG,ASD,T,11-KT,17a,20b-DHP)synthesis accumulates.The increased steroid hormones stimulated the transcription of related synthase(CYP11A1,3β-HSD,17β-HSD3,11β-HSD2,20β-HSD)up-regulated.Changes of these indexes in the testis caused hormone imbalance,uncoordinated development of germ cells at all levels,poor sperm cell metamorphosis,decreased sperm count,loose tissue structure,and pathological damage such as edema and vacuolation.This may be an important mechanism for affecting reproductive activity.