Leptin's long-distance call to the pancreas

December 22, 2008

Rube Goldberg-the cartoonist who devised complex machines for simple tasks-would have smiled at one of leptin's mechanisms for curbing insulin release. As Hinoi et al. show, the fat-derived hormone enlists the sympathetic nervous system to prevent bone-making cells from releasing a molecule that prods the pancreas to discharge insulin.

The study will appear online December 22, 2008 (www.jcb.org) and in the December 29, 2008 print issue of The Journal of Cell Biology (JCB).

In the fight against obesity and diabetes, leptin is one of the good guys. Mice lacking the hormone become corpulent, and their sky-high insulin levels eventually lead to diabetes. Leptin can curtail insulin release directly. But there's also a back-door route that researchers are still trying to piece together. Scientists knew that leptin nudges osteoblasts, cells known for building bone but that also manufacture osteocalcin, a protein that stimulates insulin release. Hinoi et al. tested whether leptin acts on the pancreas through osteocalcin.

Leptin channels many of its effects through the nervous system. The team thus tested whether the hormone relied on the sympathetic nervous system, the branch that pumps out adrenaline during emergencies but at other times emits a hormonal trickle to maintain a low level of stimulation. This baseline activity was lower in mice lacking the leptin receptor, indicating a connection between leptin and the sympathetic nervous system. When that connection was broken by deleting the adrenaline receptor from mice osteoblasts, insulin levels shot up.

The researchers then dosed mice with a sympathetic stimulator. Rodents lacking leptin or the adrenaline receptor on their osteoblasts turned out normal amounts of osteocalcin, but much of it was in an inert form. That result suggests leptin affects insulin release by indirectly inactivating osteocalcin. The work boosts researchers' hopes of using osteocalcin to treat diabetes-a possibility some drug companies have already started to investigate.

Rockefeller University Press

---

---

	Mastering Leptin: Your Guide to Permanent Weight Loss and Optimum Health (Third Edition) by Byron J. Richards (Author), Mary Guignon Richards (Author) First published in 2002, Mastering Leptin is the first and most in-depth book explaining the hormone leptin and its relationship to obesity and difficult weight loss, yo-yo dieting, low energy, heart disease, low thyroid, stress eating, food cravings, and hormonal imbalance. Mastering Leptin cuts through the confusion of countless ways to eat and provides individuals with a workable lifestyle for permanent weight loss. Renowned leptin expert Byron Richards, CCN analyzes over 8,500 leptin-related scientific studies and brings amazing findings to the public in an easy-to-understand format. Learn how to eat in harmony with the fat hormone leptin, reduce food cravings, improve energy, and permanently lose weight.
	The Leptin Diet: How Fit Is Your Fat? (Take Charge) by Byron J. Richards (Author) The Leptin Diet explains how to unleash the power of hormones to resolve fatigue, food cravings, thyroid problems, and body weight issues. Mastering the fat hormone leptin is the single most important factor in preventing obesity, diabetes, and heart disease. The Leptin Diet contains five simple lifestyle guidelines to get the hormone leptin into balance for permanent weight loss, increased energy, and optimum health. What is Leptin? Fat cells produce the powerful hormone leptin, a primary force instructing metabolism, weight loss, and hormone balance. Leptin communicates directly to your brain, telling the brain how much fat is in storage. It controls appetite, energy, and metabolic rate. Leptin problems are the primary reason for food cravings, overeating, faulty metabolism, the...
	The Fat Resistance Diet: Unlock the Secret of the Hormone Leptin to: Eliminate Cravings, Supercharge Your Metabolism, Fight Inflammation, Lose Weight & Reprogram Your Body to Stay Thin- by Leo Galland (Author) No more counting carbs, calories, or fat grams! This revolutionary diet plan works with your hormones to curb your appetite, boost your metabolism, and take the pounds off for good! Cutting-edge research shows that losing weight is not about carbs, calories, or even willpower—it’s about a hormone called leptin, and how it functions in your body. Leptin is your body’s natural weight-loss mechanism: it curbs your appetite, jump-starts your metabolism, and when working properly makes you literally fat resistant—you will lose weight effortlessly and efficiently and never gain those pounds back. If you’re struggling to lose weight, chances are you are “leptin resistant”—your body no longer responds to leptin, making it impossible for you to slim down. The Fat...
	The Leptin Boost Diet: Unleash Your Fat-Controlling Hormones for Maximum Weight Loss by Scott Isaacs (Author) UNLEASH THE POWER OF LEPTIN When the hormone leptin blinds with receptors in your brain, it shuts down your appetite and speeds up your metabolism! FINALLY A DIET THAT WILL WORK FOR YOU On the Leptin Boost Diet, you will correct the hormonal imbalances that have made it impossible to lose weight on other diets and: •Develop a lean body •Maintain a healthy weight •Feel more energetic •Elevate your mood •Experience restful sleep •Sharpen your mental focus END CRAVINGS AND STOP FEELING HUNGRY When short of leptin, your brain mistakenly thinks your body is starving and sends signals telling you to eat more. The Leptin Boost Diet reserves both leptin deficiency in the bloodstream and leptin resistance in the brain, ensuring that you will...
	Secrets to a Healthy Metabolism by Maria Emmerich (Author) All New September 2011 Revision! Over a third of the book is updated with the latest nutritional science. Maria is constantly researching the latest science and this edition updates all the latest information to help you get your metabolism back on track. In this book you will learn the tools to lead a healthy lifestyle that you can sustain for the rest of your life. It is based on the food science of how our bodies react to different ingredients. Using these guidelines and recipes you can lose weight or maintain a healthy weight while staying full and satisfied. This book covers the science behind nutrition and how our bodies use different elements of our food to function. The last chapter supplies recipes, pantry items, and healthy substitutes to help you use these scientific...
	The Smarter Science of Slim: What the Actual Experts Have Proven About Weight Loss, Dieting, & Exercise, Plus, The Harvard Medical School Endorsed Program To Burn Fat Permanently by Jonathan Bailor (Author), John Paine (Editor), Hillel Black (Editor), Mary Rose Bailor (Editor), Alex McVey (Editor), Astrid Jacob (Editor), Michael David McGuire (Editor), Douglas Gorenstein (Editor) As our knowledge of the human body becomes ever more exact, scientists have made remarkable leaps forward in many fields. Yet for one question that many of us would like answered--What causes the body to burn fat?--we find all sorts of confusing claims. Since we know so much about how our body works, can't science tell us the answer? As it turns out, science already has. I have spent over ten years reading thousands of fat-loss studies. Not theories promoted by diet gurus. Only the proven data. My investigation uncovered all kinds of scientific findings: - Studies stating how certain foods cripple our ability to burn fat - Scientists showing how to burn fat while eating more food - Researchers revealing how to get all the benefits...
	THE SAINT'S DIET Cooking With Dr. Clark The HCG Alternative Leptin Rich Diet For Youthful Exuberant Childlike Energy & Health by Shornick Whether seriously sick, forever tired, hoplessly depressed, allergic to everything or immensely overweight there is no healthier diet in the world that has such an effective kaleidoscope of concepts woven into it that can even compare to The Saint’s Diet. This diet reveals foods that specifically inflame the hypothalamus, which other diets use as standard supports, such as coffee and green tea. It shows the irony of using thermogenic stimulants. It goes to the absolute taproot of weight issues. It bypasses all the useless willpower pep talks with a superior sustainable process capable of liberating one from a lifelong nightmare of food addiction. Excess fat will torment every system in the body with false hormonal signaling. For this reason, the real danger in dieting has...
	Weight-Loss Apocalypse: Emotional Eating Rehab Through the hCG Protocol by Robin Phipps Woodall (Author) This book was written to start a new conversation about how Dr. Simeons' protocol has relevance, not only as a hormonal therapy, but as a means to end our national eating disorder. Instead of continuing to apply the protocol as a short-term diet, it shoulder be discussed as a real solution --a tool to end irrational eating for emotional fulfillment. This country is dealing with a crisis: an addiction to eating emotionally, and the obvious result is the overwhelming increase in obesity. Think about the number of people in our culture who eat without hunger. When you observe our nation's behavior with food, it's very clear that fat isn't what we should be obsessed about, and weight shouldn't be the target of the problem. We need a genuine desire to eat less, one that isn't dependent on...
	The Rosedale Diet by Ron Rosedale (Author), Carol Colman (Author) Finally—the ultimate diet for fast, safe weight loss, lifelong health, and longer life, based on more than twenty years of research and the latest findings on appetite and weight. Metabolic specialist Ron Rosedale, M.D., has designed the Rosedale Diet to regulate the powerful hormone leptin, which controls appetite and weight loss by telling the brain when to eat, how much to eat—and when to stop. New research shows that leptin may be one of the body's most important hunger control mechanisms. Control leptin, and you control your weight. Most people's leptin levels are out of control, causing them to overeat and to store fat rather than burn it. The only way to flip the "hunger switch" back to normal is through a diet high in healthy fats and low in carbohydrates, saturated fat, and...
	Leptin (Endocrine Updates) by V. Daniel Castracane (Editor), Michael C. Henson (Editor) This book is an edited collection of the literature on leptin beginning with the discovery of leptin and a study of its affect on animals and in humans. Chapters will focus on the discovery, history, roles and regulation of leptin in all the major areas of physiology, as well as on assay methods, phylogeny and genetics. The timing of this volume is long overdue and is the first comprehensive coverage of leptin physiology in the field.