Serum Preptin Düzeyi ve İnsülin Direnci Arasındaki İlişki

Öz

Giriş: Preptin, proinsülin benzeri büyüme faktörü-II'nin e-peptidinden türetilir. Adacık β hücre grenüllerinde bulunur ve glikoza yanıt olarak insülin ile birlikte salgılanır. Daha önce yapılan çalışmalarda, preptinin glikoz ve lipid metabolizmasında rol oynadığını öne sürülmüştür. Bu çalışmada, insülin direncine (IR) sahip hastalarda serum preptin düzeylerini araştırdık ve bu şekilde preptinin diyabetin erken teşhisinde ve izlenmesinde parametre olarak rolünü tanımlamayı amaçladık. Materyal ve Metot: Çalışmaya 49 IR hastası ve 37 sağlıklı kontrol alındı. IR varlığı, Homeostatik değerlendirme-insülin direnci (HOMA-IR) 2,7 veya daha yüksek seviyede olması ile belirlendi. Hastalardan ve kontrol grubundan açlık plazma örnekleri alındı. Serum preptin seviyeleri, bir Enzime Bağlı İmmün Sorbent Testi (ELISA) kiti ile ölçüldü. Bulgular: IR hastaları kontrol grubundan daha yüksek açlık insülin, HOMA-IR ve trigliserit düzeylerine sahipti (p <0,01). Serum preptin düzeyleri IR hastalarında sağlıklı kontrollere göre anlamlı derecede yüksekti (sırasıyla 492,00±289,23 ve 98,41±50,64; p<0,01). Aynı zamanda HOMA-IR (r = 0,43; p <0,01), açlık insülin düzeyi (r = 0,64; p <0,001),vücut kitle indeksi (r = 0,41; p <0,01) ve trigliserid düzeyi(r=0,26; p<0,05 ile pozitif korelasyon gösterdi. Sonuç: Serum preptin düzeyi IR'li hastalarda daha yüksekti. Bu bulgular preptin ve glukoz-lipid metabolizması arasında potansiyel bir bağlantı olduğunu göstermektedir. Sonuç olarak, insülin direncine sahip hastalarda yüksek preptin seviyeleri, preptinin insülin direncinin patogenezinde rol oynayabileceğini düşündürmektedir.

Anahtar Kelimeler

• Preptin,insulin rezistansı,obezite

The Relationship Between Insulin Resistance and Serum Preptin Level

Öz

Objectives: Preptin is derived from e-peptide of proinsulin-like growth factor II, is present in islet β-cell granules and is co-secreted with insulin in response to glucose. Studies have suggested that preptin plays a role in glucose and lipid metabolism. In this study, we have investigated the serum preptin levels in patient with insulin resistance (IR) and by this way, we aimed to define the role of preptin as a parameter in early diagnosis and monitoring progression of diabetes. Materials and Methods: The study included 49 IR patients and 37 healthy controls. The presence of IR was based on the Homeostatic model of assessment- insulin resistance (HOMA-IR) level of 2.7 or higher. Fasting plasma samples were obtained from the patients and the control group. The serum levels of preptin were measured with an Enzyme-Linked Immuno Sorbent Assay (ELISA)kit. Results: The IR patients had higher fasting insulin, HOMA-IR and triglyceride levels than the control subjects (p < 0.01). And the serum levels of preptin were significantly higher in IR patients than in the healthy controls (492.00±289.23 and 98.41±50.64 respectively; p<0.01). They showed a positive correlation with the HOMA-IR (r=0.43; p<0.01), the fasting insulin level (r=0.64; p<0.001), body mass index count (r=0.41; p<0.01) and triglyceride level (r=0.26; p<0.05). Conclusion: The serum preptin level was higher in patients with IR. These findings demonstrate that there is a potential link between preptin and glucose-lipid metabolism. In conclusion, high preptin levels in patients with insulin resistance suggest that preptin may play a role in the pathogenesis of insulin resistance.

Anahtar Kelimeler

• Preptin,insulin resistance,obesity

Kaynakça

1. Lin D, Chun TH, Kang L. Adipose extracellular matrix remodeling in obesity and insulin resistance. Biochem Pharmacol. 2016;119:8–16.
2. Kahn BB, Flier JS. Obesity and insulin resistance. J Clin Invest. 2000;106(4):473–81.
3. Buchanan CM, Phillips AR, Cooper GJ. Preptin derived from proinsulin-like growth factor II (proIGF-II) is secreted from pancreatic islet beta-cells and enhances insulin secretion. Biochem J 2001;360(2):431–9.
4. Cooper G, Willis A, Clark A, Turner R, Sim R and Reid K. Purification and characterization of a peptide from amyloid-rich pancreases of type 2 diabetic patients . Proc. Natl. Acad. Sci. U.S.A. 1997;84(23):8628–32.
5. Tatemoto K, Efendic S, Mutt V, Makk G, Feitner G and Barachas J. Pancreastatin, a novel pancreatic peptide that inhibits insulin secretion. Nature (London)1986;324(6096): 476–8.
6. Hutton JC, Peshavaria M, Johnston CF, Ravazzola M, Orci L. Immunolocalization of betagranin: a Chromogranin A-related protein of the pancreatic B-cell. Endocrinology. 1988;122(3):1014–20.
7. Lewitt MS, Dent MS, Hall K. The insulin-like growth factor system in obesity, insulin resistance and type 2 diabetes mellitus. J Clin Med. 2014;3(4):1561–74.
8. Buchanan CM, Peng Z, Cefre A. Preptin analogues: chemical synthesis, secondary structure and biological studies. Chem Biol Drug Des 2013;82(4):429-37.

9. Aydin S. Three new players in energy regulation: Preptin, adropin and irisin. Peptides. 2014;56:94–110.
10. Canoy D, Buchan I. Challenges in obesity epidemiology. Obesity reviews. 2007;8(supplement 1):1-11
11. World Health Organization(internet). https://www.who.int/diabetes/publications/diagnosis_diabetes2006/en//IDF Consultation. Geneva: World Health Organization; 2006. (Accessed:15.01.2019)
12. Bu Z, Kuok K, Meng J, Wang R, Xu B. The relationship between polycystic ovary syndrome, glucose tolerance status and serum preptin levels. Reprod Biol Endocrinol 2012;10(1):10.
13. Yang G, Li L, Chen W. Ann Med Circulating preptin levels in normal, impaired glucose tolerance, and type 2 diabetic subjects. 2009;41(1):52–6.