Features | Partner Sites | Information | LinkXpress
Sign In
GLOBETECH PUBLISHING LLC
GLOBETECH PUBLISHING LLC
PURITAN MEDICAL

Prolonged Fasting Promotes Immune System Regeneration

By BiotechDaily International staff writers
Posted on 17 Jun 2014
Image: Schematic flow chart of the effects of prolonged fasting on the immune system (Photo courtesy of USC).
Image: Schematic flow chart of the effects of prolonged fasting on the immune system (Photo courtesy of USC).
A new study suggest that prolonged cycles of fasting trigger stem-cell based regeneration of immune cells and the clearing out of old, damaged cells.

Researchers at the University of Southern California (USC; Los Angeles, USA), the University of Palermo (Italy), and other institutions have succeeded in demonstrating in a mouse model that fasting for 2–4 days at a time reduces circulating insulin-like growth factor 1 (IGF-1) levels and protein kinase A (PKA) activity in various cell populations, leading to signal transduction changes in long-term hematopoietic stem cells (LT-HSCs) and niche cells that promote stress resistance, self-renewal, and lineage-balanced regeneration.

The researchers also found that multiple cycles of fasting abated the immunosuppression and mortality caused by chemotherapy and reversed age-dependent myeloid-bias, supporting previous data on the protection of lymphocytes from chemotoxicity in fasting. The pro-regenerative effects of fasting on stem cells were reinforced by deficiency in either IGF-1 or PKA, and blunted by exogenous IGF-1. Prolonged fasting also protected against toxicity in a pilot clinical trial in which a small group of human patients fasted for a 72-hour period prior to chemotherapy. The study was published on June 5, 2014, in the journal Cell Stem Cell.

“Switching off the gene for PKA is the key step that triggers the stem cells to shift to regeneration; it gives the OK for stem cells to go ahead and begin proliferating and rebuild the entire system,” said corresponding author Prof. Valter Longo, PhD, director of the USC Longevity Institute. “The good news is that the body also rids itself of the parts of the system that might be damaged or old, the inefficient parts, during the fasting. If you start with a system heavily damaged by chemotherapy or aging, fasting cycles can generate, literally, a new immune system.”

According to the authors, the study has major implications for healthier aging, in which immune system decline contributes to increased susceptibility to disease as we age. By outlining how prolonged fasting cycles kill older and damaged immune cells and generate new ones, the research also has implications for chemotherapy tolerance and for those with a wide range of immune system deficiencies, including autoimmunity disorders.

Related Links:

University of Southern California
University of Palermo



Channels

Genomics/Proteomics

view channel
Image: Researchers have generated disease-free stem cells from patients with mitochondrial disease that can be converted into any cell type including neuronal progenitors (left) or heart cells (right). These could potentially be used for future transplantation into patients (Photo courtesy of Salk Institute of Biological Studies).

Methods Developed to Generate Normal Stem Cells from Patients with Mitochondrial Defects

A recent paper described two methods for converting cells from patients with mitochondrial defects into normal pluripotent stem cells that could be induced to differentiate into several different types of tissues.... Read more

Drug Discovery

view channel
Image: A new micelle delivery system for the protective polyphenols resveratrol and quercetin (mRQ) may have value in cancer chemotherapy (Photo courtesy of Oregon State University).

Micelles Containing Resveratrol and Quercetin Reverse Doxorubicin Cardiotoxicity

Cancer researchers blocked the toxic effects of the cancer drug doxorubicin (DOX) by administering it together with the plant antioxidants resveratrol and quercetin. Although in use for more than 40... Read more

Lab Technologies

view channel
Image: The Leica DM2500 LED Microscope for clinical laboratories and research applications (Photo courtesy of Leica Microsystems).

New LED Microscope Completes Line of Clinical and Research Tools

A popular microscope used for both clinical and research applications is now available with LED illumination. The Leica (Wetzlar, Germany) DM2500 and DM2500 LED microscopes represent a class of tools... Read more

Business

view channel

Teva Buys Allergan Generic Business Unit

Teva Pharmaceutical Industries (Petah Tikva, Israel) has bought the Allergan (Irvine, CA, USA) generic drugs business for USD 40.5 billion in cash and stock, solidifying its position as the world's largest generic drug maker. Under the terms of the agreement, Teva will pay USD 33.75 billion in cash and USD 6.... Read more
 
Copyright © 2000-2015 Globetech Media. All rights reserved.