DataSheet_2_Teleost Nonapeptides, Isotocin and Vasotocin Administration Released the Milt by Abdominal Massage in Male Catfish, Clarias magur.docx

In the present work the nonapeptides i.e., isotocin and vasotocin alone or in a combination were tested in C. magur to evaluate their effect on stripping by abdominal massage. Also, we used chitosan-carbon nanotube nanocomposites to conjugate the nonapetides isotocin (abbreviated as COOH-SWCNTCSPeP) and isotocin and vasotocin (COOH-SWCNTCSPePs) with the aim of sustaining the effect for a longer duration. The conjugation of nonapeptides with nanocomposites was confirmed by Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Two experiments were conducted to study the effect of naked (without nanoparticles) and conjugated nonapeptides on the milt release by stripping. Both the experiments consisted of eight treatments which included four naked groups two nanoconjugated groups and two controls. Both naked and nonconjugated formulations were successful in stripping the male catfish. The mRNA expression of selected reproductive genes was analysed to decipher the effect of nanopeptides at the molecular level. Nonapeptide treatment either naked or nanoconjugated, resulted in the upregulation of the transcript level of genes. Histological analysis revealed the concentration of spermatozoa was more in peptide injected groups than in the controls. The synergistic effects of nonapeptides and Ovatide had a positive impact on GSI. Thus, the present formulations were successful in stripping the male catfish to obtain the milt with significant reproductive success. Even though the naked groups perform better but the number of males required to fertilize the eggs in nanoconjuagted groups was smaller making it worth using for the delivery of nonapeptides.

本研究以马格拉鲶（C. magur）为实验对象，测试了单独或联合使用的九肽（nonapeptides）——异催产素（isotocin）与血管升压素（vasotocin）对腹部按摩采精效果的影响。此外，本研究使用壳聚糖-碳纳米管纳米复合材料（chitosan-carbon nanotube nanocomposites）对九肽异催产素进行偶联，所得偶联物缩写为COOH-SWCNTCSPeP；同时对异催产素与血管升压素的混合物进行偶联，所得偶联物缩写为COOH-SWCNTCSPePs，以期延长其作用时长。通过傅里叶变换红外光谱法（Fourier-transform infrared spectroscopy, FTIR）、扫描电子显微镜（Scanning electron microscopy, SEM）、透射电子显微镜（Transmission electron microscopy, TEM）、热重分析（Thermogravimetric analysis, TGA）与X射线光电子能谱（X-ray photoelectron spectroscopy, XPS），验证了九肽与纳米复合材料的偶联效果。本研究开展两组实验，分别探究游离（未偶联纳米颗粒）与纳米偶联九肽对雄性鲶鱼采精时精液释放的影响。两组实验均设置8个处理组，包括4个游离肽组、2个纳米偶联组与2个对照组。游离肽制剂与纳米偶联肽制剂均成功实现了雄性鲶鱼的采精。通过分析选定生殖相关基因的mRNA表达水平，从分子层面解析了纳米偶联肽的作用效果。无论是游离还是纳米偶联的九肽处理，均能上调相关基因的转录水平。组织学分析结果显示，肽类注射组的精子细胞浓度高于对照组。九肽与Ovatide的协同作用对性腺指数（Gonadosomatic Index, GSI）产生了积极影响。综上，本研究开发的制剂可成功实现雄性鲶鱼采精，获得的精液具有显著的繁殖成功率。尽管游离肽组的效果更优，但纳米偶联组所需的雄性亲本数量更少，因此在九肽递送方面具有应用价值。