Disease relevance of LEP

• Neutering induces changes in food intake, body weight, plasma insulin and leptin concentrations in normal and lipoprotein lipase-deficient male cats [1].
• CONCLUSIONS AND CLINICAL RELEVANCE: Changes in NEFA suppression, caloric intake, and leptin concentrations may be indicators of, and possible risk factors for, the development of obesity in cats after neutering [2].
• After feeding the test meal to overweight cats in the early morning, plasma leptin concentrations initially decreased before subsequently rising to peak 15 h later, which coincided with late evening [3].
• In the second part of the study, plasma leptin concentrations were determined in 16 cats before and after approximately 10 months of spontaneous weight gain [4].

High impact information on LEP

• Effects of interactions between interleukin-1 beta and leptin on cat intestinal vagal mechanoreceptors [5].
• In a previous study, we established that leptin controls food intake and immune responses by acting on intestinal vagal chemosensitive mechanoreceptors via a functional link with interleukin-1 beta (Il-1 beta) [6].
• Effects of leptin on cat intestinal motility [6].
• For this purpose, the effects of locally injected leptin on small intestine spontaneous EMG activity were studied in 23 anaesthetised cats [6].
• The interactions between leptin and CCK are specific ones, since other substances (phenylbiguanide, a serotoninergic agonist; substance P) known to activate the mechanoreceptors did not modify the effects of leptin [7].

Chemical compound and disease context of LEP

• After gonadectomy, plasma concentrations of glucose and triacylglycerol did not change, whereas plasma insulin and leptin concentrations increased (P < 0.05), but not coincidentally with body weight gain [8].
• This study investigated relationships between plasma leptin, insulin concentrations, insulin sensitivity and glucose tolerance in lean and overweight cats [3].

Biological context of LEP

• Leptin is involved in the control of food intake and has specific receptors in afferent vagal neurones [7].
• Adiposity signaling through insulin or leptin does not appear to mediate the energy intake effect [8].
• Energy intake and expenditure, body composition and plasma concentrations of leptin, insulin, glucose and triacylglycerol were determined during a 36-wk period in adult male (2-5 y) gonadectomized (n = 8) and intact (n = 8) normal cats and gonadectomized (n = 8) and intact (n = 8) lipoprotein lipase (LPL)-deficient cats [8].
• Leptin, body fat content and energy expenditure in intact and gonadectomized adult cats: a preliminary study [9].
• An important finding of this study is that in both lean (r=-0.79) and overweight (r=-0.89) cats, the higher the leptin concentrations, the more insulin resistant the cat, independent of the degree of adiposity [3].

Anatomical context of LEP

• Cats that have an overabundance of body fat appear to be less sensitive to the weight-normalizing action of leptin than cats of ideal body condition [10].
• These data show that feline leptin is highly homologous to leptins of other species, and expressed in adipose tissues in cats [11].
• RT-PCR analysis revealed that the leptin mRNA was expressed in adipose tissues and not detected in liver, heart, kidney, lung, pancreas. brain and skeletal muscle [11].

Associations of LEP with chemical compounds

• Additionally, cholesterol, triglyceride, leptin, and glycosylated hemoglobin concentrations were measured [12].
• RESULTS: Darglitazone-treated cats had significantly lower cholesterol, triglyceride, and leptin concentrations, compared with placebo-treated obese cats [12].
• CDNA cloning of feline leptin and its mRNA expression in adipose tissue [11].

Analytical, diagnostic and therapeutic context of LEP

• OBJECTIVE: To validate a recently developed commercially available leptin radioimmunoassay (RIA) for use with feline serum and evaluate the relationship between serum leptin concentrations and body fat mass in domestic cats [10].
• PROCEDURE: Specificity for feline leptin was evaluated by use of gel filtration chromatography and reverse-phase high-performance liquid chromatography fractionation of serum [10].
• Plasma leptin concentrations in cats: reference range, effect of weight gain and relationship with adiposity as measured by dual energy X-ray absorptiometry [4].

References