leptin and Cerebral-Hemorrhage

Angiogenesis is a vital endogenous brain self-repair processes for neurological recovery after intracerebral hemorrhage (ICH). Increasing evidence suggests that leptin potentiates angiogenesis and plays a beneficial role in stroke. However, the proangiogenic effect of leptin on ICH has not been adequately explored. Moreover, leptin triggers post-ICH angiogenesis through pericyte, an important component of forming new blood vessels, which remains unclear. Here, we reported that exogenous leptin infusion dose-dependent promoted vascular endothelial cells survival and proliferation at chronic stage of ICH mice. Additionally, leptin robustly ameliorated pericytes loss, enhanced pericytes proliferation and migration in ICH mice in vivo, and in ICH human brain microvascular pericytes (HBVPC) in vitro. Notably, we showed that pericytes-derived pro-angiogenic factors were responsible for enhancing the survival, proliferation and tube formation followed leptin treatment in human brain microvascular endothelial cells (HCMEC/D3)/HBVPC co-culture models. Importantly, considerable improvements in neurobehavioral function and hostile microenvironment were observed in leptin treatment ICH mice, indicating that better vascular functionality post ICH improves outcome. Mechanistically, this study unveiled that leptin boost post-ICH angiogenesis potentially through modulation of leptin receptor (leptinR)/Signal Transducer and Activator of Transcription 3 (STAT3) signaling pathway in pericyte. Thus, leptin may be a lucrative option for the treatment of ICH.

Topics: Animals; Cerebral Hemorrhage; Endothelial Cells; Humans; Leptin; Mice; Neovascularization, Physiologic; Pericytes; STAT3 Transcription Factor

Leptin, one of the most important adipokines, is not only an energy regulator but also a regulator of innate immunity. Inflammation plays a key role in the tissue damage after intracerebral hemorrhage (ICH), and we sought to investigate whether leptin has a detrimental effect on ICH. After the injection of a high replacement dose (0.04 mg/kg) and two pharmacologic doses (4 and 8 mg/kg) of leptin, brain water contents increased significantly compared with that of control mice (P<0.05), which was confirmed when comparing the results with leptin-deficient ob/ob and wild-type (WT) mice (78.8%±0.6% versus 79.7%±0.6%, P<0.05). The number of Ox6-positive microglia/macrophages was increased in the leptin-injected group and decreased in ob/ob compared with WT mice. Among the candidate signal transducers, an increase in signal transduction and activator of transcription 3 (STAT3) levels was found after leptin injection. When we administered NSC74859, a specific inhibitor of phosphorylated STAT3 (pSTAT3), the water content became normalized. Activity of pSTAT3 was found mainly in Ox6-positive microglia/macrophages, but not in either neurons or astrocytes. We demonstrate that leptin plays a critical role in the secondary brain injury around a hematoma and is a novel mediator of the inflammation. This detrimental effect of leptin on ICH is mediated by the STAT3 signaling pathway in inflammatory cells.

Topics: Animals; Brain; Brain Edema; Cerebral Hemorrhage; Leptin; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Signal Transduction; STAT3 Transcription Factor; Water

Leptin has recently been discussed as a novel biomarker for the clinical outcome of critical illness. This study aims to investigate the prognostic value of leptin with regard to long-term clinical outcomes in patients with intracerebral hemorrhage. In 50 healthy controls and 92 patients with acute spontaneous basal ganglia hemorrhage presenting to the emergency department of a large primary care hospital, we measured plasma leptin levels using an enzyme-linked immunosorbent assay in a blinded fashion. Plasma leptin levels on admission were considerably higher in patients than healthy controls. A significant correlation emerged between plasma leptin level and National Institutes of Health Stroke Scale score. A multivariate analysis identified plasma leptin level as an independent predictor for 6-month clinical outcomes including 6-month mortality and unfavorable outcome (Modified Rankin Scale score>2). Using receiver operating characteristic curves, we calculated areas under the curve for 6-month clinical outcomes. The predictive performance of leptin was similar to, but did not obviously improve that of National Institutes of Health Stroke Scale scores. Thus, leptin may help in the prediction of 6-month mortality and unfavorable outcome after intracerebral hemorrhage.

Topics: Aged; Biomarkers; Cerebral Hemorrhage; Female; Humans; Leptin; Male; Middle Aged; Predictive Value of Tests; Prognosis; Prospective Studies; Time Factors; Treatment Outcome

Leptin, an important hormone for body weight regulation, may be involved in the pathogenesis of cardiovascular manifestations of obesity. We tested whether leptin may be an independent risk marker for stroke in a case-referent study.. Definitive acute stroke events, defined by MONICA criteria, were identified from October 1, 1995 to April 30, 1999. Referents without known cardiovascular disease were randomly selected from a population census. Patient characteristics were taken from hospital files and leptin was analyzed in stored samples. Logistic regression analysis was used to determine possible differences in leptin levels between groups.. One hundred and thirty-seven cases with ischemic stroke and 69 cases with hemorrhagic stroke were identified. In comparison with referents, male patients with stroke had significantly higher leptin levels. Both male and female stroke patients had increased blood pressure compared with the referents. In multivariate analyses, high leptin levels were associated with both ischemic (OR = 4.89; 95% CI: 1.89-12.62) and hemorrhagic (OR = 3.86; 95% CI: 1.13-13.16) stroke in men, and with ischemic stroke in women (OR = 4.10; 95% CI: 1.45-11.62). The combination of high leptin levels and increased blood pressure (systolic or diastolic) was associated with a strong positive interaction in males with hemorrhagic stroke.. Leptin may be an important link for the development of cerebrovascular disease in the insulin resistance syndrome in men.

Topics: Aged; Aged, 80 and over; Biomarkers; Blood Pressure; Brain Ischemia; Case-Control Studies; Cerebral Hemorrhage; Diabetes Mellitus; Diastole; Female; Humans; Hypertension; Length of Stay; Leptin; Male; Middle Aged; Multivariate Analysis; Obesity; Risk Factors; Statistics as Topic; Stroke; Sweden; Systole

Leptin, important for body weight regulation, may be involved in the pathogenesis of the insulin resistance syndrome, associated with cardiovascular disease. We tested to determine whether leptin is a risk marker for first-ever stroke in a nested case-referent study.. We identified 113 patients with first-ever stroke (94 with ischemic and 19 with hemorrhagic stroke) who, before the stroke, had participated in population-based health surveys in northern Sweden. Referents were matched for sex, age, date and type of health survey, and geographic region. Blood pressure (BP), body mass index (BMI), and presence of smoking, diabetes, and hypertension were recorded. Total cholesterol, insulin, and leptin were analyzed in stored samples. Risk markers for first-ever stroke were analyzed by conditional logistic regression analysis.. Patients with hemorrhagic stroke had higher levels of BMI and systolic and diastolic BPs. Leptin levels were 72% and 59% higher in males and females, respectively, with hemorrhagic stroke versus referents. Patients with ischemic stroke more often had hypertension, diabetes mellitus, and higher fasting glucose and insulin levels. A diagnosis of hypertension and elevated systolic and diastolic BPs were significant risk markers for first-ever hemorrhagic stroke in univariate analysis. High leptin (OR=20.55; 95% CI, 1.12 to 376.7) levels together with hypertension (OR=16.28; 95% CI, 1.49 to 177.3) remained as significant risk markers in a multivariate model. The combination of high leptin and high systolic or diastolic BP were associated with a profoundly increased risk for hemorrhagic stroke (OR=22.11; 95% CI, 1.57 to 310.9). Diabetes, hypertension, and obesity (BMI >/=27), together with high levels of insulin, glucose, systolic and diastolic BP, were significant risk markers for first-ever ischemic stroke in univariate analysis. Hypertension (OR=2.10; 95% CI, 1.14 to 3.86) remained as an independent risk marker in a multivariate model.. Plasma leptin is strongly associated with an increased risk for first-ever hemorrhagic stroke, independent of other risk markers for cardiovascular disease. Leptin may be an important link in the development of cardiovascular disease in obesity.

Topics: Adult; Aged; Biomarkers; Blood Pressure; Body Mass Index; Brain Ischemia; Cerebral Hemorrhage; Cohort Studies; Female; Humans; Hypertension; Incidence; Leptin; Male; Middle Aged; Obesity; Population Surveillance; Prognosis; Proteins; Retrospective Studies; Risk Factors; Sweden