Serum, plasma, cell culture medium, salvia, breast milk and urine.

Haemolytic samples appear to show falsely high Resistin levels. Whole blood should be chilled as soon as possible following collection. Serum and plasma samples are stable for maximal 2 days at room temperature. Long-term storage at -20°C, stable for maximal 2 years. Maximum 3 freeze/thaw cycles.

Women:   7.0 ng/ml +/- 2.5 SD (referred to BMI ~ 25 kg/m²)
Men:          6.0 ng/ml +/- 2.5 SD (referred to BMI ~ 25 kg/m²)

Human

Resistin (FIZZ3) is a hormone influencing fat metabolism and inflammation processes. In humans, it is expressed in bone marrow and transported by macrophages into adipose tissue. Resistin stimulates pre-adipocyte proliferation and lipolysis of mature adipocytes probably by influencing MAPK signaling. With regard to the importance of Resistin in disorders of energy metabolism, a significant reduction could be shown in patients with anorexia nervosa. It has been demonstrated that Resistin enhances the expression of specific cell markers such as VACM-1 and ICAM-1 and thus may influence endothelial inflammatory processes, and thereby arteriosclerosis. Moreover, due to its association with Endothelin-1, Resistin also plays a role in cardiovascular diseases.

Resistin is relevant to medical conditions such as:
• Obesity
• Insulin resistance, diabetes
• Arteriosclerosis
• Inflammation
• Lipolysis

Serum, plasma, cell culture

Store samples at –20°C. Avoid repeated freezing/thawing of specimens.

Mouse, rat

This mouse/rat-Leptin EIA provides a tool for investigation of leptin effects on energy metabolism. Beside energy metabolism leptin influences several further endocrine axes.
In male mice leptin reduces the effect of starvation on testosterone, ACTH and corticosterone.
In female mice leptin delays starvation induced ovulation.

Leptin, the product of the ob gene, is a recently discovered proteohormone. It is almost exclusively produced by differentiated adipocytes and is thought to play a key role in the regulation of body weight. Leptin has an influence on the central nervous system, mainly on the hypothalamus, by suppressing food ingestion and increasing energy consumption.
Beside its influence on food intake, leptin has been shown to have a strong effect on reproduction and a number of metabolic and endocrine axes.
As leptin is of great importance for reproductive functions, infertility may be due to inadequate leptin production. The most important variable determining the circulating leptin concentration is the body fat mass as leptin level and fat mass increase exponentially.

Serum, heparin and EDTA plasma, urine, saliva, cell culture.

Normal food intake rhythm provided, samples should be collected till 2 p.m. Leptin shows a moderate circadian variation with a peak at 2 a.m., the leptin values at that time are about 30 to 100 % higher.
This variation together with the influence of food intake needs to be taken into account when blood samples are collected. Whole blood should be refrigerated as soon as possible following collection.
Samples are stable for maximal 2 days at room temperature.
Long-term storage stable for maximal 2 years at -20 °C.
Max. 5 freeze and thaw cycles.

Leptin levels depend on age and gender and must be referred to the percentage body fat (such as BMI).
Comprehensive clinical reference data are available for this test.

Human

Leptin, the product of the ob gene, is a recently discovered proteohormone. It is almost exclusively produced by differentiated adipocytes and is thought to play a key role in the regulation of body weight. Leptin has an influence on the central nervous system, mainly on the hypothalamus, by suppressing food ingestion and increasing energy consumption.
Beside its influence on food intake, leptin has been shown to have a strong effect on reproduction and a number of metabolic and endocrine axes.
As leptin is of great importance for reproductive functions, infertility may be due to inadequate leptin production. The most important variable determining the circulating leptin concentration is the body fat mass as leptin level and fat mass increase exponentially. Due to its pleiotropic effects, leptin is a valuable parameter with regard to:

• Metabolic syndrome
• Adiposity
• Cachexia and other metabolic disorders
• Eating disorders

EDTA-plasma, serum

Centrifuge freshly collected blood as soon as possible.
Sample storage before centrifugation is possible up to one hour.
Store centrifuged samples at -20 °C for longer storage if assay is not performed within 48 hours.
FGF-21 is stable up to 3 freeze and thaw cycles.
Hemolyzed or lipemic samples may cause erroneous results. 

Normal adult EDTA plasma samples (n= 32) were found to be <200 pg/ml.

Human

This “sandwich” ELISA (enzyme-linked immunosorbent assay) kit is intended for the quantitative determination of human intact FGF-21 level in EDTA-plasma or serum. This assay doesn’t detect human FGF-21 fragments. The test is useful in clinical study related to diabetes and obesity.

Fibroblast Growth Factor 21 (FGF-21) belongs to the FGF-19 subfamily, which includes FGF-19, FGF-21 and FGF-23. The FGF-19 family members are potent endocrine hormones in the regulation of a diverse physiological homeostasis.
The intact FGF-21 is a small protein comprising 181 amino acids. Administration of recombinant FGF21 lowered plasma glucose and insulin levels, reduced hepatic and circulating triglycerides and cholesterol levels, and improved insulin sensitivity, energy expenditure, hepatic steatosis and obesity in a range of insulin resistant animal models. The physiological functions of FGF-21 are relied on the intact molecular structure and amino acid sequence in its N-terminal and C-terminal region. An N-terminal truncated FGF-
21 (7-181) is a potent inhibitor that competitively inhibits the biological activity of intact FGF-21 (1-181). Therefore, it is important to measure the circulation intact FGF-21 level in the assessment of the physiological and pathophysiological condition. An assay that determines the fragment of the FGF-21 might overestimate the biological activity of the protein in test sample.
Circulation FGF-21 is a biomarker and its levels is increased in patient with nonalcoholic fatty liver disease (NAFLD), type 2 diabetes, gestational diabetes and obesity. An increase of circulating FGF-21 is also found in patient with Cushing’s syndrome, patient with lipodystrophy induced by HIV-1 and patient with chronic renal disease or end-stage renal disease (ESRD).

Clinical significance:

• Non-alcoholic fatty liver disease (NAFLD)
• Type 2 diabetes
• Gestational diabetes
• Cushing’s syndrome
• lipodystrophy induced by HIV-1
• chronic renal disease or end-stage renal disease (ESRD)

Total Adiponectin

Serum and plasma

Samples are stable for maximal 2 days at room temperature. Long-term storage up to 2 years at -20 °C or below. Maximum 5 freeze/thaw cycles.

Rat

Adiponectin is a 30kDa protein and its percentage in serum proteins is 0.01%. In vivo, it appears with different oligomers and it is mainly synthesized by adipocytes. Until now, IGF-1 is the only known natural inductor of synthesis.
Low Adiponectin levels are closely associated with insulin resistence and metabolic syndrome as well as an increased risk of type 2 diabetes mellitus and cardiovascular disease.
Today, Adiponectin is thought to act as an endogenic insulin sensitizer by decreasing excessive glucose levels without increasing insulin concentrations and by stimulating the burning of adipose tissue in muscle and liver.
Adiponectin is associated with glucose and lipid metabolism and is assumed to have direct antiatherogenic characteristics. Furthermore, it is involved in inflammatory processes.

Clinical significance:
• Obesity
• Arteriosclerosis
• Energy metabolism
• Coronary diseases

Total Adiponectin

Serum and plasma

Generally, samples should be refrigerated as soon as possible following collection. Samples are stable maximum 2 days at room temperature. Long-term storage up to 2 years at -20 °C or below. Maximun 5 freeze and thaw cycles.

Mouse

Adiponectin is a 30kDa protein and its percentage in serum proteins is 0.01 %. In vivo, it appears with different oligomers and it is mainly synthesized by adipocytes. Until now, IGF-1 is the only known natural inductor of synthesis.
Low Adiponectin levels are closely associated with insulin resistance and metabolic syndrome as well as an increased risk of type 2 diabetes mellitus and cardiovascular disease.
Today, Adiponectin is thought to act as an endogenic insulin sensitizer by decreasing excessive glucose levels without increasing insulin concentrations and by stimulating the burning of adipose tissue in muscle and liver.
Adiponectin is associated with glucose and lipid metabolism and is assumed to have direct antiatherogenic characteristics. Furthermore, it is involved in inflammatory processes.

Clinical significance:
• Obesity
• Arteriosclerosis
• Energy metabolism
• Coronary diseases
 

Total Human Adiponectin

Serum, heparin plasma, breast milk, urine, saliva, CSF, cell culture

Blood collection – fasting is recommended.
Samples are stable for maximum 2 days at room temperature. Long-term storage stable for maximum 2 years at -20 °C.
Max. 5 freeze and thaw cycles.

Comprehensive clinical reference data related to age and gender are available for this test.

Human

Adiponectin is a 30kDa protein and its percentage in serum proteins is 0.01%. In vivo, it appears with different oligomers and it is mainly synthesized by adipocytes. Until now, IGF-1 is the only known natural inductor of synthesis.
Low Adiponectin levels are closely associated with insulin resistence and metabolic syndrome as well as an increased risk of type 2 diabetes mellitus and cardiovascular disease.
Today, Adiponectin is thought to act as an endogenic insulin sensitizer by decreasing excessive glucose levels without increasing insulin concentrations and by stimulating the burning of adipose tissue in muscle and liver.
Adiponectin is associated with glucose and lipid metabolism and is assumed to have direct antiatherogenic characteristics. Furthermore, it is involved in inflammatory processes.

Clinical significance:
• Obesity
• Atherosclerosis
• Energy metabolism
• Coronary artery disease
• Metabolic syndrome
• Polycystic ovary syndrome (PCOS)