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We analyzed the serum and cerebrospinal fluid (CSF) leptin secretion and the interaction between serum leptin and CD[4.sup.+]CD[25.sup.+] regulatory T cells ([T.sub.Regs]) in naive-to-therapy relapsing-remitting multiple sclerosis (RRMS) patients. Leptin production was significantly increased in both serum and CSF of RRMS patients and correlated with IFN-[gamma] secretion in the CSF. T cell lines against human myelin basic protein (hMBP) produced immunoreactive leptin and up-regulated the expression of the leptin receptor (ObR) after activation with hMBP. Treatment with either anti-leptin or anti-leptin-receptor neutralizing antibodies inhibited in vitro proliferation in response to hMBP. Interestingly, in the RRMS patients, an inverse correlation between serum leptin and percentage of circulating [T.sub.Regs] was also observed. To better analyze the finding, we enumerated [T.sub.Regs] in leptin-deficient (ob/ob) and leptin-receptor-deficient (db/db) mice and observed the significant increase in [T.sub.Regs]. Moreover, treatment of WT mice with soluble ObR fusion protein (ObR:Fc) increased the percentage of [T.sub.Regs] and ameliorated the clinical course and progression of disease in proteolipid protein peptide ([PLP.sub.139-151])-induced relapsing-experimental autoimmune encephalomyelitis (R-EAE), an animal model of RRMS. These findings show an inverse relationship between leptin secretion and the frequency of [T.sub.Regs] in RRMS and may have implications for the pathogenesis of and therapy for multiple sclerosis. autoimmunity | tolerance | metabolism | hormones

We analyzed the serum and cerebrospinal fluid (CSF) leptin secretion and the interaction between serum leptin and CD4+CD25+ regulatory T cells (TRegs) in naïve-to-therapy relapsing-remitting multiple sclerosis (RRMS) patients. Leptin production was significantly increased in both serum and CSF of RRMS patients and correlated with IFN-γ secretion in the CSF. T cell lines against human myelin basic protein (hMBP) produced immunoreactive leptin and up-regulated the expression of the leptin receptor (ObR) after activation with hMBPI Treatment with either anti-leptin or anti-leptin-receptor neutralizing antibodies inhibited in vitro proliferation in response to hMBP. Interestingly, in the RRMS patients, an inverse correlation between serum leptin and percentage of circulating TRegs was also observed. To better analyze the finding, we enumerated TRegs in leptin-deficient (ob/ob) and leptin-receptor-deficient (db/db) mice and observed the significant increase in TRegs. Moreover, treatment of WT mice with soluble ObR fusion protein (ObR:Fc) increased the percentage of TRegs and ameliorated the clinical course and progression of disease in proteolipid protein peptide (PLP139-151)-induced relapsing-experimental autoimmune encephalomyelitis (R-EAE), an animal model of RRMS. These findings show an inverse relationship between leptin secretion and the frequency of TRegs in RRMS and may have implications for the pathogenesis of and therapy for multiple sclerosis. [ABSTRACT FROM AUTHOR]

Obesity affects about 44% of women with polycystic ovary syndrome (PCOS). Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is one of the genes involved in the differentiation of adipose tissue. In an attempt to shed light on the high percentage of obesity in PCOS, we examined polymorphisms at exons 6 and 2 of the PPAR-gamma gene in 100 PCOS patients and in 100 healthy controls matched for age and body mass index (BMI). The T allele frequency of exon 6 was significantly higher (P < 0.05) in PCOS patients compared with control women. In addition, the BMI and leptin levels were significantly higher (P < 0.05) in PCOS patients carrying the C-->T substitution than in controls. There was no significant difference in leptin levels after normalization for BMI. The Pro(12)Ala polymorphism at exon 2 was unrelated to BMI and/or leptin levels in PCOS women. In conclusion, the higher frequency of the C-->T substitution in exon 6 of the PPAR-gamma gene in PCOS women suggests that it plays a role in the complex pathogenetic mechanism of obesity in PCOS, whereas the Pro(12)Ala polymorphism does not seem to affect BMI in PCOS women.