المستخلص
Type 1 diabetes mellitus (T1DM) is a chronic autoimmune disease that progresses with pancreatic β-cell destruction and insulin dependence. Irisin is produce among other sources by skeletal muscle and is involved in the induction of the process of converting white adipose tissue (WAT) into brown adipose tissue (BAT). The precursor for this myokine is transmembrane protein FNDC5 (fibronectin type III domain containing 5).The purpose of this study was to measure the blood levels of irisin in T1DM patients and compare them to serum levels of irisin in healthy individuals. Additionally, it sought to determine the relationship between irisin levels and T1DM as well as the connections between irisin levels in newly diagnoses, and previously diagnosis T1DM. The enzyme-linked immune sorbent assay (ELISA) was used to determine the levels of serum irisin. Fasting blood sugar (FBS), lipid profile and urea were determined by enzymatic methods, glycated hemoglobin (HbA1c) was measured by (HPLC), and Creatinine (by kinetic method).
The study was conducted at National Center of Diabetes (AL- Mustansiria University) on 120 subjects divided into two groups according to Insulin therapy: newly diagnosed T1DM [group I (n= 37)] and those who previously diagnosed [group II (n= 53)]. 30 healthy: subject aged 18 to 30 years were examined as control group.
The results of the current study were summarized to:
- Parametric BMI and age showed non-significant (p<0.05) in patient groups in compared to control group.
- The results of the present study referred to significant increase (p≤0.05)in metabolic factors (FSG and HbA1c) in patients groups as compare to control.
- The comparison of (FSG and HbA1c) according to gender showed non- significant in the two groups of patients and control.
- Lipid profile (TG, TC, LDL, and VLDL) levels were altered between groups. Significant increase (p ≤ 0.05) were observed when compared with control group, whereas, HDL showed non-significant (p>0.05) in two group compared with control.
- Lipid profile (TG, TC, LDL, and VLDL) according to gender the change was significant in newly diagnosis and non-significant in previously diagnosis HDL showed a non-significant in the two groups, compared to control.
- Serum levels of irisin were significantly lower (p ≤ 0.01), in patients as compared to the control group. In addition, irisin level was significantly lower in-group I compared to group II.
- Serum irisin has been correlated negatively to fasting serum glucose, and glycated hemoglobin, whereas it positively correlated to serum lipid profile.
- The receiver operating characteristic curve (ROC) analysis has done to
- identify the cut off value for the parameters. There are two cut off in newly diagnosis The Irisin cutoff value was > 7.02 with sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and Area under curve of 97.3 %, 96.7 %, 97.3 %, 96.7% and 0.996 (0.989- 1.000). The Irisin cutoff value in previously diagnosis was > 8.74 with sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and Area under curve of 94.3 %, 96.7 %, 98.0 %, 90.6% and 0.969 (0.936- 1.000). The present results indicates that Irisin considered as an excellent diagnostic marker.
Conclusion: According to the results obtained in this study, it can been concluded that lower irisin levels were determined in T1DM patients compared to the control group. The association of highest irisin amounts to an insulin therapy and a better glycaemic control. May suggest that insulin therapy can be effective in the synthesis of irisin. Furthermore, the measurement of serum irisin levels could also be useful as laboratory marker to monitor T1DM severity and therapy response.
