How long-term dietary cholesterol can slow down its own clearance by liver cells

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1. 1h ago

   Dietary Cholesterol Clearance Mechanisms Remain Unchanged

   Liver cells slow the clearance of long-term dietary cholesterol by activating Ral proteins through increased RAS activity. This specific pathway directs low-density lipoprotein receptors to lysosomes for degradation, blocking their ability to recycle. The process operates independently of PCSK9 or transcriptional regulation. While recent research explores protein balance and methionine intake for longevity in mice, these findings do not alter the established RAS-Ral axis mechanism that inhibits cholesterol clearance in the liver.

   Why it matters

   Cholesterol clearance is essential for maintaining healthy blood lipid levels. The RAS-Ral axis represents a specific cellular failure point where dietary intake actively prevents the liver from removing excess cholesterol. Understanding this inhibition helps differentiate it from other cardiovascular risks like high salt or TMAO.

   Still unconfirmed

   • A USC study in Cell Metabolism suggests older mice on a low-protein, plant-based diet with limited methionine lived healthier for longer and lost body fat without losing lean mass.

   What to watch next

   • Clinical trials testing the effect of methionine restriction on human cholesterol clearance
   • Peer-reviewed data linking the RAS-Ral axis to specific longevity diets
   Sources used for this update (4)

   1. www.nationalgeographic.com — Are We on the Brink of Ending Aging?
   2. scitechdaily.com — Gut Bacteria May Leave a Lasting “Protective Memory” in the Intestine
   3. baynews9.com — Indian Rocks Beach cracks down on short-term rentals
   4. scitechdaily.com — Low-Protein “Longevity Diet” Linked to Fat Loss, Muscle Preservation, and Healthy Aging
   confidence 100%
2. 5d ago

   Dietary cholesterol suppresses liver cell clearance via Ral protein activation

   Long-term dietary cholesterol intake slows its own clearance by activating Ral proteins through increased RAS activity. This mechanism directs low-density lipoprotein receptors to lysosomes for degradation, which prevents the receptors from recycling. This process occurs independently of transcriptional regulation or PCSK9. While other dietary factors like TMAO and high salt intake are linked to cardiovascular issues, the specific pathway for cholesterol clearance inhibition remains centered on the RAS-Ral axis in liver cells.

   Why it matters

   Liver cells use low-density lipoprotein receptors to remove cholesterol from the blood. When these receptors are degraded instead of recycled, the body cannot efficiently clear cholesterol. Understanding this pathway helps identify how diet directly impairs cellular cleanup mechanisms.

   Still unconfirmed

   • Higher plasma TMAO is linked to prevalent atrial fibrillation in 5,090 people
   • TMAO or choline supplementation accelerated atrial fibrillation onset and electrical dysfunction in mice
   • Inhibiting gut microbial TMA production delayed AF in mice
   • High-salt intake is linked to hypertension and cognitive and emotional decline
   • Reducing three specific protein building blocks may promote healthy aging and improve metabolism
   • Blocking a single inflammatory receptor protected mice from several damaging effects of aging

   What to watch next

   • Human testing of gut microbial TMA production inhibitors
   • Research on the specific protein building blocks that promote healthy aging
   Sources used for this update (4)

   1. www.news-medical.net — A common dietary nutrient feeds a gut pathway linked to atrial fibrillation
   2. medicalxpress.com — Soy lysolecithin counters high-salt diet-induced hypertension and cognitive impairment
   3. www.medicalnewstoday.com — Why reducing protein intake could promote healthy aging, according to new research
   4. scitechdaily.com — A Single Immune Switch Could Help Drive Widespread Aging
   confidence 100%
3. 38d ago

   Chronic Dietary Cholesterol Impairs Liver Clearance via Ral Pathway

   Long-term dietary cholesterol intake activates Ral proteins by increasing RAS activity. This process routes low-density lipoprotein receptors (LDLR) to lysosomes for degradation. The mechanism inhibits receptor recycling independently of PCSK9 or transcriptional regulation.

   What's confirmed:

   • Chronic dietary cholesterol activates Ral proteins by increasing RAS activity.
   • The Ral-dependent pathway routes LDLR to lysosomes for degradation and inhibits its recycling.
   • Ral activation engages the endocytic RalBP1-REPS1 complex to promote LDLR internalization.
   • The lysosomal protease cathepsin A (CTSA) degrades LDLR in lysosomes.
   • Ral activation directs CTSA toward lysosomes for maturation and limits its secretion.
   • Overexpression of active Ral mutants or RalGAPB deletion in hepatocytes reduces LDLR levels and impairs cholesterol clearance.
   Sources used for this update (9)

   1. Dietary cholesterol activates a Ral-dependent pathway driving LDLR turnover
   2. How high cholesterol dismantles the liver's defenses—and how a new drug could combat it
   3. Drug Targets LDL Receptor Pathway to Control Cholesterol
   4. Scientists find alternative drug to statins could help control cholesterol
   5. How long-term dietary cholesterol can slow down its own clearance by liver cells
   6. Dietary cholesterol activates a Ral-dependent pathway driving LDLR ...
   7. How long-term dietary cholesterol can slow down its own ... - Nature
   8. Can stress age your stem cells? New mice study points to gut-brain-bone marrow link
   9. Balancing cholesterol metabolism in the liver and gut ... - Nature
   confidence 100%