leptin and Multiple-System-Atrophy

Topics: Blood Pressure; Female; Humans; Hypotension, Orthostatic; Leptin; Male; Multiple System Atrophy

Topics: Blood Pressure; Female; Humans; Hypotension, Orthostatic; Leptin; Male; Multiple System Atrophy

Advanced multiple system atrophy (MSA) patients exhibit malnutrition with hypocholesterolemia and hypoalbuminemia, similar to patients with other neurodegenerative disorders, but also display unexpected fat accumulation. To understand this paradox, we herein examined the relationship between fat accumulation, measured by triceps skinfold thickness (TSF), and plasma leptin in 29 MSA patients at three clinical stages: activities of daily living (ADL) 1: ambulatory with/without wheelchair; ADL2: bedridden/communicable; and ADL3: bedridden/non-communicable. TSF and leptin were higher while cholesterol and albumin were lower in advanced stage ADL3 than in ADL1 or ADL2. Although a correlation was observed between leptin and TSF, a stepwise regression analysis identified the first significant positive predictor of leptin as the duration of autonomic symptoms (p < 0.005) rather than TSF. Leptin/TSF strongly correlated with the duration of autonomic symptoms (p < 0.001). These results implicate leptin resistance through autonomic dysfunction in the paradoxical fat accumulation observed in patients with advanced MSA, but not to be seen in the cholesterol metabolism.

Topics: Adiponectin; Adult; Aged; Anthropometry; Body Mass Index; Cholesterol; Fatty Acids; Female; Humans; Leptin; Male; Middle Aged; Multiple System Atrophy; Regression Analysis; Retrospective Studies; Statistics, Nonparametric; Up-Regulation

Patients with multiple system atrophy (MSA) frequently exhibit orthostatic hypotension (OH). Leptin, an adipose-derived hormone, contributes to the sympathetic control of blood pressure (BP), and loss of leptin may cause OH. We aimed to clarify the relationship between leptin and OH in MSA. Serum leptin levels were measured in 36 patients with MSA, 25 patients with other atypical parkinsonian disorders (APDs), including progressive supranuclear palsy-Richardson syndrome and corticobasal syndrome, and 26 control subjects. Blood samples were obtained after fasting for 12h. In MSA patients, baseline BP was measured in the recumbent position after a 3-min rest, and orthostatic changes in BP were evaluated after 0-3 min of standing. Serum leptin levels did not differ significantly between MSA patients (5.9 ± 0.8 ng/ml), other APD patients (5.2 ± 0.8 ng/ml), and controls (6.1 ± 1.3 ng/ml; P=0.8). In MSA patients, serum leptin levels correlated significantly with body mass index (P=0.01), but not baseline BPs (systolic BP, P=0.20; diastolic BP, P=0.44) or orthostatic drop in BP (systolic BP, P=0.13; diastolic BP, P=0.58). Our observations indicated that the circulating level of leptin was preserved, and OH occurred independent of the leptin level in MSA patients.

Topics: Aged; Autonomic Nervous System Diseases; Blood Pressure; Female; Humans; Hypotension, Orthostatic; Leptin; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Supranuclear Palsy, Progressive

Leptin exists in a free form and a receptor-bound form. Protein-bound rather than free leptin levels may be associated with regulation of muscle sympathetic nerve activity (MSNA). We determined MSNA and bound leptin concentrations in 25 men [age, 29 +/- 6 yr, body mass index (BMI), 24 +/- 3 kg/m(2)]. Baroreflex sensitivity was measured using phenylephrine and nitroprusside infusions. We measured bound leptin in patients with central (multiple system atrophy, n = 8; age, 59 +/- 8 yr; BMI, 23 +/- 2 kg/m(2)) and peripheral autonomic failure (pure autonomic failure, n = 4; age, 71 +/- 10 yr; BMI, 25 +/- 3 kg/m(2)). MSNA was correlated with protein-bound leptin concentrations (r(2) = 0.35; P < 0.01) but not with free leptin levels (r(2) = 0.09). MSNA at baseline was 15 +/- 2 bursts x minutes(-1) in subjects with lower and 24 +/- 3 bursts x minutes(-1) in subjects with higher bound leptin concentrations (P < 0.05). Blood pressure as well as baroreflex regulation of heart rate and MSNA was similar in both groups. Phenylephrine and nitroprusside responses were similar. Patients with multiple system atrophy and autonomic failure featured similar bound leptin levels. We conclude that protein-bound rather than free leptin levels are correlated with basal sympathetic outflow in normotensive, nonobese men. This relationship cannot be explained by a direct central nervous effect of protein-bound leptin. Instead, protein-bound leptin may increase sympathetic vasomotor tone indirectly via a baroreflex mechanism.

Topics: Adult; Autonomic Nervous System Diseases; Baroreflex; Blood Pressure; Body Mass Index; Body Weight; Humans; Leptin; Male; Multiple System Atrophy; Obesity; Parasympathetic Nervous System; Regression Analysis; Sympathetic Nervous System