Objective To discuss the correlation between the letpin level and the pathogenesis of avascular necrosis of the femoral head (ANFH) by measuring the leptin expression of the femoral head in patients with ANFH. Methods Between July 2009 and February 2011, 16 patients with ANFH (including 10 cases of steroid-induced ANFH and 6 cases of alcohol-induced ANFH, ANFH group) and 11 patients with proximal femur fracture (control group) were included in the experiment. There was no significant difference in age, weight, and body mass index between 2 groups (P gt; 0.05). The peripheral blood and bone marrow were extracted to measure the blood lipid level and the free fat (FF) content, respectively. ELISA was used to detect the levels of the leptin, soluble leptin receptor (sLR), osteoprotegerin (OPG), and soluble receptor activator of nuclear factor κB (sRANKL); the leptin biological activity and the activity of osteoclasts were calculated. The femoral head specimens were harvested to count leptin-positive cells by immunohistochemical staining. Results No significant difference in the blood lipid level was found between 2 groups (P gt; 0.05), but the FF content in ANFH group was significantly lower than that in control group (t= — 14.230, P=0.000). The intramedullary leptin expression was found in both groups; however, the intramedullary leptin level in ANFH group decreased significantly when compared with the level in control group (t=4.425, P=0.002). There were significant differences in the levels of leptin, OPG, and sRANKL between 2 groups (P lt; 0.05). The leptin biological activity of ANFH group was significantly lower than that of control group (P lt; 0.05), but the activity of osteoclasts of ANFH group was significantly higher than that of control group (P lt; 0.05). There was a positive correlation between the leptin level and leptin biological activity (r=0.922 7, P=0.000 0), and a negative correlation between the leptin level and OPG content (r= — 0.396 2, P=0.040 8), FF content (r= — 0.806 1, P=0.000 0), while it had no correlation between the leptin level and sLR and sRANKL content (P gt; 0.05). Conclusion Intramedullary expression and bioactivity of the leptin decrease significantly in ANFH patients, which may play an important role in the pathogenesis of ANFH.
Objective To assess the correlation between central sleep apnea (CSA) and serum leptin (LEP) levels in patients with chronic heart failure. Methods The level of serum LEP and N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured by forward-looking method in patients with chronic heart failure who underwent polysomnography during hospitalization from December 2015 to April 2017 in Department of Cardiology and Respiratory Medicine, Renmin Hospital of Wuhan University. And its correlation with CSA was analyzed. Patients were divided into three groups according to the left ventricular ejection fraction (LVEF), and then according to the presence or absence of CSA into CSA group and without SDB group. Results Of the 71 patients with heart failure, 31 had LVEF≥45%, 19 were between 35% and 45% and 21 were≤35% ; 32 of whom were CSA and 39 had no SDB. The lEP concentrations in the LVEF subgroup of CSA groups were significantly lower than those in the control group without SDB, with significantly higher levels of NT-proBNP. Logistic regression showed that CSA was associated with logarithmic LEP (lnLEP) (OR=0.047, 0.030, 0.021, P<0.05). In severe heart failure (LVEF≤35%) group, high NT-proBNP was the risk of CSA (OR=5.942, P=0.045) and the incidence of CSA was as high as 71.4%, which was significantly higher than other groups. However, after adjustment for confounding factors such as age, sex and body mass index (BMI), the correlation no longer existed (OR=6.432, P=0.105). Moreover, CSA with severe cardiac insufficiency had lower LEP than those without SDB. After adjustment for confounding factors such as age, sex and BMI, CSA and lnLEP remained significantly correlated (OR=0.013, P=0.002). Meanwhile, linear correlation analysis also showed that NT-proBNP was negatively correlated with lnLEP (R=–0.751, P<0.001). After adjusting for age, sex, and BMI, this relationship still existed (R=–0.607, P=0.004). Conclusion Decreased levels of leptin and elevated NT-proBNP in patients with chronic heart failure may indicate the presence of CSA.
ObjectiveTo explore the relationship between the -2548 G/A functional polymorphism in the 5′ promoter region of the leptin gene and gallstones. Methods The -2548 G/A polymorphisms of leptin gene were determined by polymerase chain reactionrestriction fragment length polymorphism technology (PCRRFLP) in 118 patients with cholesterol gallstones and 53 normal control subjects. Then the allele and genotype distribution were studied. Results The distribution of leptin2458 G/A in two groups was statistically significantly different: the genotype frequency of AA+GA of patients in gallstone group was higher than that in control group (χ2=4.251, P=0.039). AA+AG genotype had 2.813 times greater risk for gallstone disease compared with GG genotype (OR=2.813, 95% CI=1.020-7.757). Allele frequency distribution in the two groups was different: the allele frequency of A of patients in gallstone group was higher than that in control group (χ2=5.791, P=0.016). The risk of gallstone disease in the A alleles carriers was 1.777 times as higher as the carriers of G alleles (OR=1.777, 95% CI=1.110-2.844). ConclusionThe -2548 G/A polymorphism in the 5′ promoter region of leptin gene is significantly correlated with the gallstones. The A alleles of leptin may be a genetic factor which contributes to individual susceptibility for gallstone, while the G alleles of leptin may be a genetic factor that prevents people from gallstone.
Myocardial remodeling is a common pathological physiology change for a variety of heart diseases under stimulation such as stress or ischemia. The engine body will release a lot of cytokines to promote the change of myocardial structure and ultimately lead to heart failure. Myocardial remodeling includes myocardial cells remodeling and the extracellular matrix remodeling. In recent years, we find that the function of adipose tissue is not only about energy storage, buffering to protect, supporting and filling, but also has a powerful function of secretion. Adipose tissue can secrete various adipocytokines, such as leptin, adiponectin, visfatin, omentin, angiotensin Ⅱ, and so on. Current studies have shown that adipocytokines and myocardial remodeling are intimated. And this article will summarize the function of adipocytokines on myocardial remodeling.
ObjectiveTo investigate the role of leptin receptor gene Gln223Arg polymorphism in pathogenesis of asthma. MethodsOne hundred and eighty-five asthmatic outpatients and inpatients in the Qingdao Municipal Hospital between June 2009 and May 2012 were recruited in the study.Two hundred and seven healthy volunteers were recruited as control.Peripheral blood was sampled from all subjects for measuring serum leptin level by ELISA,and analyzing leptin receptor gene Gln223Arg genotypes by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) in white blood cells. ResultsThere was significant difference in frequency distribution of leptin receptor gene Gln223Arg genotype between the asthma group and the health group (χ2=6.173,P=0.013,OR=1.697,95%CI 1.115-2.585).The GG genotype was associated with a 1.895-fold increased risk for asthma than the GA+AA genotype (χ2=7.283,P=0.007,OR=1.895,95%CI 1.187-3.024).The serum leptin level of the GG genotype group was significantly higher than that in the GA+AA genotype group[(2.56±1.47) ng/mL vs.(2.16±1.66) ng/mL]. ConclusionLeptin receptor gene Gln223Arg polymorphism is correlated with asthma, and the G allele might be the genetic factor that contributes to individual susceptibility for asthma by causing high serum leptin level.
Obesity is closely related to thyroid function. The concentration of thyroid stimulating hormone (TSH) in obese patients is higher than that in the general population, and TSH will decrease accordingly after weight loss. Leptin is a bridge linking obesity and thyroid hormones, which can affect the release of TSH. There are many kinds of weight-reducing drugs that target the thyroid gland. Among them, thyroid hormone receptor-specific agonists may be potential drugs for future obesity treatment, but further studies are still needed.
Objective To investigate the effect and mechanism of leptin (LEP) on the osteoblastic differentiation of hBMSCs in vitro. Methods Whole bone marrow culture method was appl ied to culture hMBSCs and hBMSCs at passage 3 were divided into groups A, B, C, D, E and F, and when cell attachment was evident, 400, 200, 100 and 50 ng/mL LEP, 100 ng/mLBMP and common nutrient medium were added into each group, respectively. ALP staining and mineral ized nodules staining were conducted at 7 and 21 days after culture, respectively. And inverted phase contrast microscope observation was performed. ALP activity and osteocalcin (OCN) level of hBMSCs in each group was detected at 7, 14 and 21 days after culture to select the best induced concentration of LEP on osteoblastic differentiation. For groups of B, E and F at 7 days after culture, RT-PCR was adopted to detect the expression of such osteogenesis-related genes as core-binding factor α 1 (Cbfα1), ALP, Col I and OCN mRNA. Results At 7 days after induced culture, the ALP staining result showed that the endochylema in groups A, B, C, D and E were stained blue and the endochylema in the group F was sl ightly positive. At 21 days after induced culture, the mineralized nodules staining showed that cells in groups A, B, C, D and E were stained positively and cells in group F were negative. At 7, 14 and 21 days after culture, ALP and OCN activities in group B were less than that of group E (P lt; 0.05), but significant higher than that of groups A, C, D and F (P lt; 0.05), the optimal concentration of LEP was 200 ng/mL. At 7 days after culture, group F witnessed no expression of Cbfα1, ALP, Col I and OCN mRNA, while groups B and E witnessed expressions of all those indexes, but the expressions in group B were less than those of group E. Conclusion LEP can stimulate osteoblastic differentiation of hBMSCs in vitro, and the possible mechanism is its role of promoting the expression of osteoblastic related genes.
Objective To investigate the effect of leptin on fibroblast proliferation and collagen synthesis as to elucidate that fibroblasts play a role in leptin’s effect on wound healing. Methods Purified dermal fibroblasts were derived from sucking wistar rat skin and exposedto leptin at concentration of 0, 10, 50, 100, 200, and 400 ng/ml. The survived fibroblasts were assessed by the colorimetric thiazolyl blue (MTT) assay. Replication of fibroblast was quantified by the incorporation of 3H-thymidine. Collagen synthesis of fibroblast cell was measured by the incorporation of 3H-proline into collagenasesensitive protein. Results The absorption of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 0.082±0.013, 0.091±0.018 was higher than that of control group 0.063±0.010, P＜0.05. The incorporations of 3H-thymidine of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 379±101 cpm,326±33 cpm were significantly higher than those of control group 219±56 cpm, P＜0.05. The incorporations of 3H-proline of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 911±55 cpm, 1 072±259 cpm were significantly higher than that of control group 679±176 cpm, P＜0.05. Conclusion Leptin can promote rat cutaneous fibroblast proliferation and collagen synthesis in vitro. This suggests that cutaneous fibroblast plays a role in leptin’s promoting skin wound healing and it may be one of the main mechanisms by which leptin enhances skin wound healing.
Objective To investigate the relatingship between leptin receptor gene Gln223Arg polymorphism and obstructive sleep apnea hyponea syndrome (OSAHS) in Han population in Southwest China. Methods Two hundred and fifteen cases of subjects (including 116 cases in OSAHS group and 99 cases in control group) were selected in Han population in Southwest China. Polymerase chain reaction (PCR) was used to analyse Gln223Arg leptin receptor gene polymorphism. The levels of serum LEP and TI were determined by double antibody sandwich enzyme-linked immunosorbent assay (ELISA). Simultaneous determination of body mass index (BMI) and neck circumference (NC) and waist circumference (WC) were conducted. Results In the OSAHS group, the leptin receptor gene polymorphism Gln223Arg GG, AA and GA genotype frequency was 0.854, 0.017 and 0.129, respectively. G allele and A allele frequency frequency was 0.918 and 0.082, respectively. In the control group, leptin receptor gene polymorphisms Gln223Arg GG, AA and GA genotype frequency was 0.840, 0.020 and 0.14,respectively. G allele and A allele frequency was 0.90 and 0.10, respectively. Genotype frequencies of the two groups were not statistically significant (χ2=0.784, P>0.05). There were differences in BMI, WC and NC between the OSAHS patients with GG and the OSAHS patients with (GA+AA) genotype (P<0.05), but no difference was found in LEP and TI levels (allP>0.05). In control, mild, moderate and severe OSAHS group, the levels of serum LEP and TI were increased gradually, and the difference was statistically significant (allP<0.05). Conclusions Gln223Arg leptin receptor genotype polymorphisms may be involved in obesity, but they have no relationship with the incidence of OSAHS in Han population in Southwest China. In OSAHS patients, Gln223Arg polymorphism has no relationship with LEP or TI. Patients with OSAHS have hyperleptinemia and hyperinsulinemia.
Objective To investigate the role of inflammatory factors like serumleptin, adiponectin,interleukin-6( IL-6) , and C-reactive protein ( CRP) in the systemic inflammatory response of smokinginduced COPD. Methods Thirty male Wistar rats were randomly divided into three groups, ie. a high-dose smoking group, a low-dose smoking group, and a control group. Serum leptin, adiponectin, IL-6, and CRP levels were measured by ABC-ELISA. Results The serum leptin and adiponectin levels in both smoking groups decreased significantly compared with the control group( P lt; 0. 05) , while the difference was not significant between the two smoking groups ( P gt; 0. 05) . The serum IL-6 and CRP levels in both smoking groups increased significantly compared with the control group( P lt; 0. 05) , which were higher in the highdosesmoking group than those in the low-dose smoking group( P lt;0. 05) . Conclusions Smoking increases the serum levels of IL-6 and CRP, but reduces the serum levels of leptin and adiponectin in rats. These results suggest that leptin, adiponectin, IL-6, and CRP may be involved in the systemic inflammatory response of smoking-induced COPD.