Navigation Links
Cholesterol Mystery Solved By Nobel Laureates

A 72 year old mystery about cholesterol synthesis which has been bugging scientists for so long has finally been cracked by Nobel laureates. //

The Shoenheimer effect has long been unexplained, but not now. The first evidence for end-product feedback regulation of a biosynthetic pathway was demonstrated when Rudolph Shoenheimer observed that mice synthesized large amounts of cholesterol when fed a low-cholesterol diet, but this synthesis stopped when the mice were fed cholesterol.

In later years, many details of this cholesterol feedback were worked out, but the main mechanism by which cells in the liver sense cholesterol and thus regulate cholesterol production remained unknown.

Joseph Goldstein and Michael Brown finally solve the mystery of the Shoenheimer effect. The authors show that Insig (insulin-induced gene) proteins are essential components of this cholesterol feedback response. They create mice lacking the two mammalian Insig genes -– Insig1 or Insig2 in the liver. On a normal chow diet, the mice over accumulate cholesterol and fats in the liver, but levels of SREBP's and other SREBP target genes (molecules that sense cholesterol and regulate its synthesis) were not reduced. Normally, cholesterol intake reduces SREBP and the genes that synthesize cholesterol and fat, but this response was dysfunctional in the transgenic mice such that fat and cholesterol synthesis was not suppressed. The transgenic mice also had dysregulated levels of HMG-CoA reductase protein, the precursor for cholesterol synthesis.

The data presented indicate that the entire pathway for SREBP processing functions in the liver. Further, this pathway is responsible for the synthesis of cholesterol as well as the feedback suppression of synthesis when cholesterol is taken in from the diet.

Source: By Journal of Clinical Investigation
'"/>




Page: 1

Related medicine news :

1. Low Cholesterol Linked to Severe Depression and Violent Behavior in Men
2. Eating More Often May Help Lower Cholesterol
3. Caution On Use of Cholesterol Drugs
4. High Cholesterol linked to Alzheimer’s diseas
5. Cholesterol Drug Helps After Angioplasty
6. Cholesterol lowering drugs increase neuropathy risk
7. Almonds Improve Cholesterol
8. Cholesterol-lowering therapy benefits older people also
9. Cholesterol lowering drugs aid people after heart transplant
10. New Cholesterol gene linked to Alzheimers
11. Children’s Cholesterol Matter
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:2/13/2016)... ... February 13, 2016 , ... With FCPX Overlay Embers ... footage all within Final Cut Pro X. Each user can select from up to ... angle of view, blur, focus offset, hue, saturation, value, contrast, glow, and more all ...
(Date:2/13/2016)... Tennessee (PRWEB) , ... February 13, 2016 , ... ... Herrington School of Nursing with an in-kind gift of a VeinViewer® Vision ... students as they learn how to start an IV and draw blood, combining ...
(Date:2/13/2016)... ... 13, 2016 , ... DDi , a Makro company, ... for its expertise in eClinical Solutions. DDi has built its solution competency with ... of global clients. DDi provides smarter technology for Clinical Development, Regulatory and Enterprise ...
(Date:2/12/2016)... ... February 12, 2016 , ... The law firm of Morrow, Morrow, ... The purpose of these scholarships is to encourage applicants to pursue a degree ... employment within these two parishes. , “We have available jobs in St. Landry ...
(Date:2/12/2016)... ... February 12, 2016 , ... CDRH Enforcement Trends: , Back to the Future , Feb. 25, ... As Winston Churchill said, “Those who don’t learn from history are doomed to repeat it.” ... they come knocking this year. But that takes time. , Take a close look ...
Breaking Medicine News(10 mins):
(Date:2/12/2016)... February 12, 2016 ... auf den ungedeckten medizinischen Bedarf bei Lungen- ... seines klinischen Forschungsprogramms bekannt. Das Programm, das ... Verbesserungen ihrer respiratorischen Funktionen und anderer klinischer ... ein Medizintechnikunternehmen, das sich auf den ungedeckten ...
(Date:2/11/2016)... , Feb. 11, 2016 Stem cells are ... characterized by self-renewal and the capacity to differentiate into ... new discovery, as the first mouse embryonic stem cells ... not until 1995 that the first culturing of embryonic ... cells were not produced until 2006 As a result ...
(Date:2/11/2016)... , Feb. 11, 2016  Walgreens has committed to ... states and Washington, D.C. as part ... that was commended by shareholder advocacy organization As You Sow. ... You Sow. "Many people hold on to unneeded drugs because ... have tragic consequences." --> Conrad MacKerron , ...
Breaking Medicine Technology: