Effects of feeding with corn gluten meal on trypsin activity and mRNA expression in Fugu obscurus

Abstract

The molecular regulation of the trypsin activity and the effects of corn gluten meal (CGM) on the trypsin activity and gene expression in Fugu obscurus were examined. The fish were fed with diets containing 0, 50, 100, 150, and 200 g kg⁻¹ CGM for 60 days. The trypsin activity and mRNA levels in the intestine, stomach, and hepatopancreas were measured before and after the experimental feeding. Enzyme activity was highest in the intestine, and mRNA expression was highest in the hepatopancreas prior to feeding the experimental diets. The effect of dietary CGM on the trypsin activity was dependent on the concentration. Enzyme activity was significantly lower in the hepatopancreas and stomach of the 200 g kg⁻¹ treatment group than in control group. In contrast, activity was enhanced in the stomach of the 100 g kg⁻¹ treatment group. Different amounts of CGM in the diets also resulted in significant changes in the trypsin mRNA levels in all three tissues. The trypsin mRNA expression in stomach, hepatopancreas, and intestine increased with increasing CGM from 0 to 10% and decreased with increasing CGM from 10 to 20%. The trypsin mRNA expression was highest in the 100 g kg⁻¹ treatment group, which was significantly higher than that of in the control. In addition, the changes in the trypsin mRNA expression levels were not reflected by changes in the trypsin activity. Our results suggest that the trypsin activity is regulated not only at the transcription level but also during translation and posttranslational modification.

Performance of juveniles of Pseudoplatystoma fasciatum fed graded levels of corn gluten meal

“…Based on in vitro assays, Moyano López et al (1999) concluded that inhibition of protease activity in S. aurata was positively correlated with dietary CGM levels, even though CGM protein is considered of high biological value (Robaina et al, 1997;Pereira & Oliva-Teles, 2003;National Research Council, 2011). Zhong et al (2011) found that trypsin activity is regulated by the amount of CGM used as a partial replacement for conventional fish meal, and observed that the trypsin activity decreased significantly at a concentration of 20% CGM in the diets for Fugu obscurus. The authors hypothesize that the amino acid composition of the diet changes the substrate specificity of trypsin, even though protein content is unchanged.…”

“…Because CGM has a low-fiber content and no anti-nutritional factors, it could be considered as a good fish meal alternative ingredient, and its use as dietary protein source has been investigated for some freshwater and marine, cold water or subtropical fishes (Robaina et al, 1997;Regost et al, 1999;Mente et al, 2003;Pereira & Oliva-Teles, 2003;Gómez-Requeni et al, 2004;Zhong et al, 2011). However, data on the use of corn gluten meal as a dietary protein source for neotropical species is scarce.…”

Capn4 mRNA level is correlated with tumour progression and clinical outcome in clear cell renal cell carcinoma

“…qRT-PCR was performed as described previously. 27 Briefly, reverse transcription was performed using SuperScript TM II RT (Invitrogen Corp.) as per the manufacturer's protocol. TaqMan Õ gene expression assays (Applied Biosystems, Foster City, CA, USA) were used to quantify Capn4 mRNA and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), which was used as an internal control.…”

Dietary protein requirement of juvenile obscure puffer,Takifugu obscurus

“…The annual production of the fish has continued to rise owing to the large body size, rapid growth and high market value. However, only a few studies have reported nutritional information for the species, including optimum protein requirement (Yang & Yang ), apparent digestibility coefficients of selected protein feed ingredients (Zhong, Han, Hua & Zhou ), corn gluten meal (Zhong, Qian, Hua & Zhou , ; Zhong, Hua, Yuan & Zhou ), chitosan and probiotics (Hua, Zhou, Zhang & Zhou ). It is suggested that the optimum dietary protein level for juvenile obscure puffer should be 46–49% (Yang & Yang ).…”