الفهرس 
Sialic acidOnly 14 pages are availabe for public view
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Abstract
Diabetes mellitus (DM) refers to a group of common metabolic disorders that
share the phenotype of hyperglycemia. Several distinct types of DM are caused by
a complex interaction of genetic and environmental factors. Depending on the
etiology of DM, factors contributing to hyperglycemia include reduced insulin
secretion, decreased glucose utilization, and increased glucose production. The
metabolic dysregulation associated with DM causes secondary pathophysiologic
changes in multiple organ systems that impose a tremendous burden on the
individual with diabetes and on the health care system. Sialic acid acts as cofactor of many cell surface receptors, e.g., insulin receptor and is positively
associated with most of the serum acute phase reactants. In human plasma, large
quantity of sialic acid is found as a component of orosomucoid, alpha-1-
antitrypsin, haptoglobin, ceruloplasmin, fibrinogen, complement proteins, and
transferrin. Some of these sialylated glycoproteins are called acute phase
reactants, and such substances rapidly increase in concentration after the onset
of an inflammatory reaction or injury. Hypothesis has also been made that a
cytokine-induced acute phase response is an integral part of the pathophysiology
of T2DM, which leads to elevated serum sialic acid level. In diabetic nephropathy,
there is a greater increase in sialic acid due to the damage of the vascular
endothelial cells and it is considered as a newly established potential risk factor
for the development of diabetic nephropathy.
This is a cross-sectional prospective study which was carried out on 50
subjects. All patients were selected from those attending the out patient Diabetes
clinic at Banha University Hospital between July 2016 and July 2017. Among
studied patients 15 patients were males and 35 were females. Age ranged from
45 to 82 with a mean age of 58 years.
Patients were classified into 3 groups :
group A : T2DM with diabetic retinopathy and it comprises 25 patients group B : T2DM without diabetic retinopathy and it comprises 15 patients group C : healthy volunteers and it comprises 10 .
The inclusion chriteria included were the following:
Type 2 diabetic patients
Type 2 diabetic patients with retinopathy.
The exclusion chriteria were the following:
Type1 DM.
Liver cirrhotic patients.
Any endocrinological disorders.
Alcohol intake.
Pregnancy
Malignancy
Any acute and chronic inflammatory disorders.
For all studied cases after giving their informed consent ,the following done:
1-Detailed medical history taking with special stress on age ,sex ,body mass
index ,smoking state ,type and duration of diabetes ,medications and
complications.
2-Complete physical examination.
3-Laboratory tests:
Fasting & postprandial plasma glucose level , cholesterol, TG, HbA1C,
Serum creatinine , blood urea , estimated GFR, 24 hr urinary albumin,
Serum sialic acid level.
4- Dilated fundus examination.
The results of the study showed the following:
A Positive significant correlation between serum sialic acid level and
parameters of glycemic control (FPG, PPS & HbA1c), s.creatinine, bl.urea,
24hr urinary albumin, s.TG, s.cholesterol, duration of D.M., BMI and degree
of DR
No significant correlation between sialic acid and Age of patient at onset of
discovery of D.M .
The mean value of FPG, PPG, HbA1c, BMI, s.cholesterol, s.triglycerides
,s.creatinine , Bl.urea , 24hr urinary albumin,degree of DR and sialic acid
level were significantly high in group I patients compared to group II&III
patients .
The mean value of FPG, PPBG, HbA1C, cholesterol, triglycerides,
creatinine, urea, 24 hours urinary albumin, degree of DR and Sialic acid
level were highly significant in group I patients compared to group III.
The mean value of FPG, PPG and HbA1c were non significant between
group I & group II .
The degree of DR and sialic acid level were highly significant in group I
patients compared to group II.
The mean value of s.cholesterol and s. triglycerides were significant in
group I patients compared to group II.
The mean value of FPG, PPG, HbA1c, s.cholesterol, s. triglycerides and sialic
acid level were significantly high in group II patients compared to group III.
FPG, PPBG, HbA1c, 24 hours albumin and sialic acid level are considered as
a significant predictor of degree of DR.
Parameters of glycemic control (FPG ,PPBG, HbA1c) are considered as a
significant predictor of sialic acid level.
This results could be explained by the inflammation and endothelial dysfunction
play an important role in pathogenesis of T2DM. Interleukin 6 (IL-6) and Creactive
protein (CRP) and sialic acid are considered physiological markers of
subclinical systemic inflammation. Sialic acids are terminal components of the non
reducing end of carbohydrate chains of glycoproteins and glycolipids. More than
50% of the total SA in serum comes from the acute-phase proteins. Free SA
appears to be cleared from plasma by the kidney in a similar manner to
creatinine, being filtered by the glomerulus, but not reabsorbed by the tubules.
So there is an increase in sialic acid level in diabetic patients and a greater
increase when retinopathy developed.