ABSTRACT
Objective To observe the protective effect of growth differentiation factor 11(GDF11) on myocardial injury and the changes of myocardial apoptosis in type 2 diabetic C57BL/6J mice.Methods Sixty male C57BL/6J mice weighing 20-25 g were randomly divided into three groups: control group (control), type 2 diabetes mellitus group (DM) and GDF11 intervention group (DM + GDF11).To establish mouse model of type 2 diabetes, the mice were fed with high fat and high sugar diet for 4 weeks, and i.p.injected consecutively three times of streptozotocin (STZ) in a dose of 60 mg/kg.After the continuous high-fat and high-sugar diet for 4 weeks, the cardiac function was detected by small animal ultrasound, TUNEL staining was used to detect the apoptosis in myocardium, and the expressions of cleaved-caspase-3, Bcl-2, Bax were measured.Results Diabetic injury significantly reduced the left ventricular ejection fraction and left ventricular short axis shortening rate, and increased myocardial apoptosis.Recombinant GDF11 protein significantly improved cardiac function and reduced myocardial apoptosis.Conclusions Exogenous GDF11 can significantly reduce myocardial apoptosis and improve heart function after diabetic injury.
ABSTRACT
Objective To purify asprosin protein expressed in Escherichia coli expression system and to study its effect on cardiac function.Methods Coding sequence of asprosin was obtained from GenBank.Codon optimization was performed according to the codon preference of E.coli.After gene synthesized, recombinant plasmid was made.Asprosin was then induced and purified by Ni-affinity purification.The mouse model of impaired cardiac function was established by ligating and relaxing the left anterior descending coronary artery.30 mice were randomly divided into 3 groups: sham operation group (sham), cardiac dysfunction group (MI/R) and cardiac dysfunction plus injection of recombinant asposin protein group (MI/R+rAsp).The left ventricular function was detected by echocardiography to determine the improving effect of recombinant asprosin protein on cardiac function.Results After prokaryotic expression and purification, the purity of the target protein was higher than 95%, and the endotoxin content was less than <0.1 EU/μg protein, which was suitable for cell and animal studies.After the recombinant asprosin protein was given, the left ventricular function of the mice was improved significantly (P<0.05).Conclusions Asprosin acts as a myocardial protective molecule to improve cardiac function.