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Association of leptin receptor gene Q223R polymorphism on lipid profiles in comparison study between obese and non-obese subjects.

OBJECTIVES Leptin is a hormone secreted from adipocytes. It regulates metabolism and energy homeostasis through the leptin receptor (LEPR) which is localized centrally in hypothalamus as well as in peripheral tissues. The aim of this study was to investigate the association of leptin receptor gene Q223R polymorphism on obesity in association with body mass index (BMI), lipid parameters, plasma leptin levels and homeostasis model assessment of insulin resistance (HOMA-IR). DESIGN AND METHODS The study included 110 obese and 90 non-obese subjects. The LEPR Q223R polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Plasma leptin levels, serum lipid and antropometric parameters were measured. RESULTS No association was found between LEPR gene Q223R polymorphism and BMI in both study and control groups. Strikingly study group with non-obese subjects and with the RR genotype (homozygous mutant) had significantly higher serum total cholesterol (p<0.001) and low density lipoprotein cholesterol (LDL-cholesterol) levels (p<0.05) than QR (heterozygous) and QQ (wild type) genotypes. In obese group, subjects with the RR genotypes had significantly higher triglycerides (p<0.05) levels, waist (p<0.05) and hip circumferences (p<0.001) than the QQ and QR genotypes. CONCLUSIONS Our results suggest that the LEPR gene Q223R polymorphism has an association with waist and hip circumferences in obese group but no direct association with obesity although there is a significant influence on lipid profile both in obese and non-obese subjects.

Association of the Ala16Val MnSOD gene polymorphism with plasma leptin levels and oxidative stress biomarkers in obese patients

Chronic oxidative stress is a major characteristic of obesity. Manganese superoxide dismutase (MnSOD) is an antioxidant enzyme known to be present within mitochondria and is considered a main defense against oxidative stress. The aim of this study was to investigate the association between the MnSOD gene Ala16Val polymorphism in obesity in terms of body mass index (BMI), lipid parameters, plasma leptin levels, homeostasis model assessment of insulin resistance (HOMA-IR), and oxidative stress biomarkers. The study included 150 obese and 120 non-obese subjects. The MnSOD Ala16Val polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Plasma leptin levels, serum lipid, superoxide dismutase (SOD), malondialdehyde (MDA), and anthropometric parameters were measured. No association was found between the MnSOD gene Ala16Val polymorphism and BMI in the study or control group. Strikingly, in the study group, obese subjects with the VV genotype had significantly higher plasma leptin levels (p<0.001) than those with the AA and AV genotypes. Serum total cholesterol (p<0.01) and MDA (p<0.001) levels were significantly higher in subjects with the VV genotype for MnSOD in the obese and non-obese groups. In the obese group, subjects with the VV genotype had significantly lower SOD (p<0.001) activity than the AA and AV genotypes. Our results suggest that the MnSOD gene polymorphism was associated with leptin levels and superoxide dismutase activity in the obese group but had no direct association with obesity. Moreover, the Ala16Val polymorphism has a significant effect on lipid profiles and MDA levels in both obese and non-obese subjects.

Fatty acid composition and anticancer activity in colon carcinoma cell lines of Prunus dulcis seed oil

Abstract Context: Almond oil is used in traditional and complementary therapies for its numerous health benefits due to high unsaturated fatty acids content. Objectives: This study investigated the composition and in vitro anticancer activity of almond oil from Northern Cyprus and compared with almond oil from Turkey. Materials and methods: Almond oil from Northern Cyprus was obtained by supercritical CO2 extraction and analyzed by GC-MS. Almond oil of Turkey was provided from Turkish pharmacies. Different concentrations of almond oils were incubated for 24 and 48 h with Colo-320 and Colo-741 cells. Cell growth and cytotoxicity were measured by MTT assays. Anticancer and antiprolifetarive activities of almond oils were investigated by immunocytochemistry using antibodies directed against to BMP-2, β-catenin, Ki-67, LGR-5 and Jagged 1. Results: Oleic acid (77.8%; 75.3%), linoleic acid (13.5%; 15.8%), palmitic acid (7.4%; 6.3%), were determined as the major compounds of almond oil from Northern Cyprus and Turkey, respectively. In the MTT assay, both almond oils were found to be active against Colo-320 and Colo-741 cells with 1:1 dilution for both 24 h and 48 h. As a result of immunohistochemical staining, while both almond oils exhibited significant antiproliferative and anticancer activity, these activities were more similar in Colo-320 cells which were treated with Northern Cyprus almond oil. Discussion and conclusion: Almond oil from Northern Cyprus and Turkey may have anticancer and antiproliferative effects on colon cancer cells through molecular signalling pathways and, thus, they could be potential novel therapeutic agents.

Association between leptin G-2548A gene polymorphism, plasma leptin levels and lipid profiles in Turkish Cypriot obese subjects / Kıbrıslı Türk obez kişilerde leptin G-2548A gen polimorfizmi ile plazma leptin seviyeleri ve lipid profili arasındaki ilişki

Abstract Objective: Leptin (LEP) is a metabolic and neuroendocrine hormone which is present in the circulation in amounts proportional to fat mass that acts to reduce food intake and increase energy expenditure thereby regulating body weight homeostasis. Various polymorphisms are shown to be present in LEP gene which play important roles in obesity and obesity-related metabolic biomarkers. The aim of this study was to investigate the association of one of these polymorphisms, leptin gene G-2548A polymorphism, on obesity in association with body mass index (BMI), lipid parameters, plasma leptin levels and homeostasis model assessment of insulin resistance (HOMA-IR). Methods: The study included 110 obese and 90 non-obese subjects. The LEP G-2548A polymorphism was determined by polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP). Plasma leptin levels, serum lipid and antropometric parameters were measured. Results: No association was found between LEP gene G-2548A polymorphism and BMI in both study and control groups. Strikingly study group with obese subjects and with the AA genotype had significantly higher serum total cholesterol (p<0.05) than GA and GG genotypes. In obese group, subjects with the AA genotypes had significantly higher leptin (p<0.05) levels than the GG and GA genotypes. Conclusion: Our results suggest that the LEP gene G-2548A polymorphism may not be considered as a genetic risk factor for obesity in Turkish Cypriot population. However, the G-2548A polymorphism appear to be important in regulating leptin and total cholesterol levels in obese group through leptin gene expression and signaling. Özet Amac: Leptin (LEP), dolaşımdaki miktarı vucuttaki yağ kutlesi ile orantılı olan metabolik ve noroendokrin bir hormondur. Leptin gıda alımını azaltarak ve enerji harcanmasını artırarak vucut ağırlığı homeostazını duzenlemektedir. LEP geninde bulunan bircok polimorfizmin obezite ve obezite ile ilişkili metabolik biyobelirteclerde onemli rol oynadığı gosterilmiştir. Bu calışmanın amacı leptin gen G-2548A polimorfizmi ile obezite, vucut kitle indeksi (VKİ), lipit parametreleri, plazma leptin seviyesi ve homeostatik model değerlendirme indeksi (HOMA-IR) arasındaki ilişkinin belirlenmesidir. Metod: Calışma 110 obez ve 90 obez olmayan birey icermektedir. LEP G-2548A polimorfizmi belirlenmesi polimeraz zincir reaksiyonu- restriksiyon parca uzunluğu polimorfizmi (PCR-RFLP) ile gercekleştirilmiştir. Calışma kapsamında plazma leptin ve serum lipit seviyeleri, antropometrik parametrelerin olcumu yapılmıştır. Bulgular: Calışma ve kontrol gruplarında LEP gen G-2548A polimorfizmi ile VKİ arasında ilişki saptanmamıştır. Calışma grubunda AA genotipine sahip obez kişilerin total kolesterol seviyesinin GA ve GG genotipine sahip kişilere gore istatistiksel olarak anlamlı derecede yuksek olduğu gozlemlenmiştir (p<0.05). Ayrıca AA genotipine sahip obez kişilerin leptin seviyelerinin GA ve GG genotiplerine gore daha yuksek olduğu belirlenmiştir (p<0.05). Sonuc: Sonuclarımız LEP G-2548A gen polimorfizminin Kıbrıslı Turk populasyonunda obezite icin genetik bir risk faktoru olmadığını gostermektedir. Fakat obez kişilerde G-2548A polimorfizminin, leptin gen ekspresyonu ve sinyali uzerine olan etkisi ile bağlantılı olarak leptin ve total kolesterol seviyelerinin duzenlenmesinde onemli bir etkisinin olduğunu duşundurmektedir.