Resistance To Leptin Contributes To Obesity

e increased potency of leptin in lean mice receiving the protein via ICV infusion and those receiving subcutaneous injections shows that the central nervous system, in particular the hypothalamus, is an important site of leptin action," says Friedman. "Indeed, chronic ICV infusions of very low doses of leptin replicate the weight-reducing effects of much higher doses of leptin given by injection. The basis for this apparent difference is not clear, but may suggest that the transport of leptin across the blood-brain barrier, which allows leptin to enter the brain from the body's blood stream, may be an important step in the body's processing of leptin's signal."

Specifically, in normal, lean mice, injecting leptin subcutaneously at an infusion rate of 200 ng per hour, for example, led to an increase in blood levels, from 5 to 7 ng/milliliter, and resulted in a 5 percent reduction in weight. A doubling of leptin levels led to a 9 percent reduction in weight, while a five-fold increase in leptin levels yielded a 15 percent weight loss.

Other lean mice receiving leptin through ICV infusion rapidly lost fat, reaching their lowest weight by the eighth day of treatment and maintained it for the remainder of the 30-day infusion period. The mice reduced their food intake to its lowest level, a drop of more than 50 percent, by the third day, but their food intake crept back to original levels by the eighth day. After the 30 days of ICV, the researchers replaced the cerebrospinal fluid and the mice quickly recovered their weight by eating more food.

To compare leptin's affects via injection and ICV infusion among overweight mice, the researchers selected strains of mice with different types of obesity. One type, the Diet Induced Obese (DIO) mouse, is lean when fed regular mouse chow, but has an inherited predisposition to develop obesity when fed a diet in which 45 percent of the calories are from fat.

The second strain, the New Zeala

Contact: Marion E. Glick
Rockefeller University

Page: 1 2 3 4 5

Related biology news :

1. Resistance exercise resets the body clock
2. Insect antibiotics Resistance is futile!
3. Resistance training complements aerobic exercise for women
4. K-State Researchers Study Pest Resistance Management
5. Maggots Could Help Address Problems Of Antibiotic Resistance
6. In The Genes: Extra Belly Fat, Insulin Resistance Linked
7. Researchers Report Emergence Of Antibiotic Resistance During Vancomycin Therapy
8. A "Fossil" Virus Involved In AIDS Drug Resistance?
9. Alcohol Consumption, Resistance To Its Effects Related To Levels Of Neurotransmitter, Say UW Researchers
10. Scientists Locate A Genetic On/Off Switch In Diphtheria; Find May Yield Antibiotics That Wont Boost Bacterial Resistance
11. Local Approaches To Combating Antibiotic Resistance Are Doomed To Failure

Post Your Comments:
TAG: Resistance Leptin Contributes Obesity

(Date:9/24/2015)... Publiceringsförbud fram till: ... Kerv ( http://kerv.com ), det Londonbaserade ... första kontaktlösa betalningsring på kickstarter.com i ett ... för massproduktion via crowdfunding.       ... Kerv-bärare kan göra direkta kontaktlösa betalningar ...
(Date:9/10/2015)... Sept. 10, 2015 Pursuant Health has ... to create an interactive, image-based health risk assessment ... wellness kiosk.  The unique assessment quantifies user results ... that suggests an individual,s biological age based on ... measured by the kiosk. Comprised of ...
(Date:9/8/2015)... , Sept. 8, 2015  Affectiva, global ... Emotion as a Service, a new data solution, ... Based on Affectiva,s highly accurate and patented ... analytics capabilities, slated to transform industries such as ... development, retail, customer experience, online education, HR, automotive, ...
Breaking Biology News(10 mins):
(Date:10/9/2015)... Governor Tom Wolf announced today that Adaptimmune ... T-cell receptor cancer immunotherapy treatments, will create at least ... Pennsylvania , and today,s announcement ... high-paying jobs will be created with this project," said ... sustained funding for the life science sector and increased ...
(Date:10/9/2015)... Oct. 9, 2015  DePuy Synthes Trauma* announced today ... Q-PACK ®  Technology**, the only pre-hydrated demineralized cancellous ... procedures (foot and ankle, hand and wrist), including fusion, ... here at the 2015 Orthopaedic Trauma Association (OTA) Annual ... scaffold for new bone growth) and osteoinductive 2,3 ...
(Date:10/9/2015)... ... October 09, 2015 , ... ... the current methods of separating those cells from their surroundings for research, diagnostics, ... the cells. , To address this, Ann Arbor-based startup Akadeum Life Sciences ...
(Date:10/8/2015)... ... October 08, 2015 , ... Researchers at the University of Washington (UW) ... providing a new tool to study how diseases like dementia, Alzheimer's, and brain tumors ... and Ruikang Wang of the UW Department of Bioengineering, today in the Journal ...
Breaking Biology Technology:
Cached News: