Beneficial effects of leptin on weight control in obese people
Leptin, the protein product of the obesity gene (Ob gene), is a 16 kDa, 146 amino acid residue and a blood-borne protein secreted from white adipocytes. Leptin has received considerable attention for its potential for the therapeutic treatment of human obesity. Obesity, defined as an excess of body fat relative to lean body mass, is a prevalent medical disorder which poses significant risk to human health and may result in life-threatening conditions such as Type II or non-insulin-dependent diabetes mellitus (NIDDM), elevated blood lipids, heart disease and hypertension (high blood pressure). The precise cause of human obesity is not clear. However, recent discovery of the metabolic hormone leptin which is produced by adipose tissue from obese gene has generated enormous attention for its possible theraputic effects for overweighted patients.
Leptin functions as the afferent signal the afferent signal in a negative feedback loop that regulates food intake, energy consumption, bone formation and body weight. In addition, leptin also functions in angiogenesis and participate in invasiveness of kidney and colonic epithelial cells. This adipocyte-derived hormone is associated with the feeling of satiety, may excert many other diverse biological functions e.g. control of reproduction and triggering of puberty, or regulating the T-lymphocyte-mediated immune response. These actions are elicited by way of binding leptin to a high affinity receptor proteins e.g. in the hypothalamus which are expressed in various tissues. The leptin receptor belongs to the cytokine receptor family. Most of leptin in human is in the bound form in lean individuals, but in the free form in obese patients. Isoforms of the leptin receptor are discovered in multiple tissues, including the brain. Circulating leptin levels in human are increased in obesity and regulated by feeding, fasting, and body weight changes. In addition, it has been found the stage of puberty and gender in both children and adults may also influence leptin levels.
Leptin’s effects on various functions such as food intake and energy expenditure may be mediated centrally through changes in neurotransmitters such as hypothalamic neuropeptide Y expression that is in charge of the regulation of the secretion of gonadotropic hormones and and energy intake and expenditure in turn. Leptin functions as a main link between nutrition and the function of most other physiologic systems. In normal health conditions, the assimilation, storage and utilization of nutrition energy form a highly integrated homeostatic system. The balance between energy expenditure and food intake influences the level of energy stores and body weight. There’s a “set point” to indicate the condition of coordinated or inconsistent regulation by control centers in the central nervous system. When at their set point, the human body produce a certain amount of leptin and a state of energy balance is in turn maintained. In both lean and obese people weight loss leads to a decreased plasma levels of leptin, which results in a state of positive energy balance and many other physiologic responses. This indicates that leptin plays an significant role in the pathogenesis of eating disorders and obesity. This adipocyte-derived hormone is thought as a mediator of long-term regulation of energy balance, suppression of food intake and thereby inducing weight loss. Leptin conveys its appetite suppressing signals through binding to the specific signaling form of its receptor in hypothalamus and by passing the blood-brain barrier, as a result it constitutes a feedback mechanism that regulates the adipose tissue mass.
It’s is confirmed plasma leptin levels in human correlate with fat stores and respond to changes in energy balance. People lacking leptin tend to develop severe obesity as a result of energy imbalance which means there’re diminished energy expenditure and increased food intake. In obese people the circulating levels of leptin in humans correlate in proportion to the high adiposity. This suggests that the connection between human obesity and insensitivity to leptin. Both the intrinsic sensitivity to leptin and the rate of leptin production alternate and this results in different body weight. The profound effects of leptin on regulating the energy balance make it a promising candidate for weight loss drug therapies to treat obesity, diabetes, and other reproductive abnormalities. Patients with low level of leptin because of mutations in the leptin gene may have morbid obesity from infancy and have various hormonal abnormalities such as hypogonadotropic hypogonadism and insulin resistance. Physiological replacement with recombinant leptin is effective in losing weight for these patients. The administration of recombinant leptin can be performed intramuscularly, intravenously, intraperitoneal, or through other parenteral routes.
I do second Yaoming. Sweating in gym is not my cup of tea.
What about swimming ?
Or cycling for long stretch ...
I am 18 mos post-op for RNY gastric bypass. I a still relatively a newbie. This has been ...
Good article...things that I knew..nice to have it reassured... 
Tips: Apart from the regular 30 minutes of moderate intensity exercise, such as walking and jogging, you can also do ...
Can you elaborate more on how can fast food be a treatment for obesity.