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Guido Kroemer

University of Paris Descartes

Guido Kroemer is a professor at the University of Paris Descartes specializing in immunology, cancer biology, aging, and autophagy. His research investigates mechanisms of regulated cell death, including apoptosis, ferroptosis, and immunogenic cell death. His publications also explore cancer immunotherapy, gut microbiota interventions in oncology, and therapeutic targets in metabolic and age-related diseases.

38 claims checked on air: 3 context 1 contradicted 2 overstated 28 supported 4 unverified 3 flagged

What they said on air - flagged

0:21:30overstatedvery lowDr. Guido Kroemer on Autophagy, Caloric Restriction Mimetics

In mice, alternate-day intermittent fasting extends lifespan to the same extent as 30% caloric restriction without resulting in a permanent reduction in body weight.

"in mice, you can obtain exactly the same longevity extension that you would obtain with 30% of caloric restriction by intermittent fasting... the intermittently fasted mouse has the same weight as a normally fed mouse. In difference with the calorically restricted mouse, it weighs also 20 to 30% less. And in spite of this difference in the body weight, intermittent fasting allows for lifetime expansion in the same way as does caloric restriction." (said at 0:21:30)

While some rodent studies have shown that alternate-day intermittent fasting can extend lifespan without reducing overall body weight due to compensatory hyperphagia on feeding days, this effect is highly conditional rather than universal. Preclinical research demonstrates that the impact of every-other-day feeding on body weight and longevity in mice is strongly dependent on genetic background, age of onset, and fasting regimen. In certain inbred strains (such as C57BL/6J), intermittent fasting does lead to significant body weight reduction, and large-scale assessments across genetically diverse mice demonstrate that continuous caloric restriction generally provides more robust lifespan extension than intermittent fasting regimens.

0:33:32contradictedhighDr. Guido Kroemer on Autophagy, Caloric Restriction Mimetics

Yeast cells placed in a glucose medium shift from oxidative phosphorylation to glycolysis by destroying most of their mitochondria through mitophagy.

"The easiest example is yeast that you suddenly place in a glucose-containing medium to allow for the fermentation of glucose in wine or beer production. So these yeast cells don't need much oxidative phosphorylation and they essentially rely during the process on glycolysis. So they adapt to this change by destroying most of their mitochondria by mitophagy." (said at 0:33:32)

The claim states that transferring yeast to a glucose-containing medium causes the cells to adapt by destroying most of their mitochondria through mitophagy. In Saccharomyces cerevisiae, high-glucose conditions actually repress and suppress mitophagy (for example, by maintaining low expression of the essential mitophagy receptor Atg32). Conversely, mitophagy is induced by glucose starvation, carbon depletion (such as ethanol depletion), or stationary phase growth, rather than by glucose exposure.

0:48:21overstatedvery lowDr. Guido Kroemer on Autophagy, Caloric Restriction Mimetics

Long-term clinical efficacy of chemotherapy depends on inducing cancer cell death that elicits an anti-cancer immune response via autophagy induction.

"chemotherapy must provoke this cell death in a way that it later leads to an immune response. And so, if you have a long-term effect of chemotherapy for years or decades, that continues beyond removal of the drug. It is due to an anti-cancer immune response. And so, since this is so important, the capacity of the chemotherapeutic agent to induce autophagy is actually required for the long-term efficacy of the treatment." (said at 0:48:21)

The speaker generalizes findings from the immunogenic cell death (ICD) paradigm to all long-term chemotherapy efficacy. Preclinical studies in mouse models and cancer cell lines (such as those by Michaud et al., 2011, 2012) established that certain chemotherapeutics (e.g., anthracyclines, oxaliplatin) require premortem autophagy to release ATP, recruit dendritic cells and T cells, and achieve durable immune-mediated tumor control. However, asserting that any long-term remission lasting years or decades from chemotherapy is universally dependent on autophagy induction overstates the evidence. Chemotherapeutic agents possess diverse mechanisms of cytotoxicity (e.g., direct DNA damage, mitotic arrest, cellular senescence) that can eliminate tumor clones without ICD, and autophagy in many clinical contexts can conversely promote chemoresistance and tumor survival rather than antitumor immunity.

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