Search bioRxiv⌕ Search

Biology subjects

Strauss, E.

Publications and source records attributed to Strauss, E..

4 recordsLinked to original sources

Sex-dependent effects of a gestational ketogenic diet on offspring birth and lifespan

Low-carbohydrate, high-fat ketogenic diets (KDs) are used to treat drug-resistant epilepsy, and other potential benefits for treating neurological disorders, metabolic syndrome, and cancer are being explored. In addition to these and other medical applications, KDs have also become popular for rapid weight-loss and enhancing athletic performance. However, the effects of exposing developing offspring to KDs during pregnancy (gestational KD) are poorly understood, and especially their long-term health consequences. In this study, we investigated the effects of a partial gestational KD during the second half of pregnancy in mice and assessed the consequences on the offspring over their entire lifespan compared to offspring exposed to a control diet. We found that a gestational KD significantly reduced dams litter size and litter mass and altered the sex ratio at birth, reducing the proportion of female offspring, which also had lower body mass early in their life. In contrast, male offspring exposed to a gestational KD suffered a significantly reduced lifespan and a late-onset increase in body mass. We found no evidence that our KD diet influenced adult offspring behavior (locomotion, anxiety, depression, circadian rhythms, food and water consumption) or reproduction. These findings highlight the potential of even a partial maternal exposure to a KD to have surprisingly detrimental effects on offspring health and longevity, and thus raising concerns about its use during pregnancy.

physiology↗

Targeting cancer with small molecule pan-KRAS degraders

Despite the high prevalence of cancers driven by KRAS mutations, to date only the G12C mutation has been clinically proven to be druggable via covalent targeting of the mutated cysteine amino acid residue (1). However, in many cancer indications other KRAS mutations, such as G12D and -V, are far more prevalent and small molecule concepts that can address a wider variety of oncogenic KRAS alleles are in high clinical demand (2). Here we show that a single small molecule can be used to simultaneously and potently degrade 13 out of 17 of the most prevalent oncogenic KRAS alleles, including those not yet tractable by inhibitors. Compared with inhibition, degradation of oncogenic KRAS results in more profound and sustained pathway modulation across a broad range of KRAS mutant cell lines. As a result, KRAS degraders inhibit growth of the majority of cancer cell lines driven by KRAS mutations while sparing models without genetic KRAS aberrations. Finally, we demonstrate that pharmacological degradation of oncogenic KRAS leads to tumour regression in vivo. Together, these findings unveil a new path towards addressing KRAS driven cancers with small molecule degraders. One-Sentence SummaryThe most prevalent KRAS variants which drive tumour growth in a major share of cancer patients can be targeted with a single small molecule degrader.

pharmacology and toxicology↗

High syphilis seropositivity in European brown hares, Lower Saxony, Germany

Treponema paraluisleporidarum infects lagomorphs and is a close relative of the human syphilis-bacterium Treponema pallidum. There is paucity of information on the epidemiology of hare syphilis and its relationship to rabbit- and human-infecting Treponema. We have found a high seropositivity (405/734) for Treponema paraluisleporidarum-infection in hares of Lower Saxony, Germany.

ecology↗

Mutations in the pantothenate kinase of the malaria parasite P. falciparum confer resistance or hypersensitivity to diverse pantothenate analogues

The malaria-causing blood stage of Plasmodium falciparum requires extracellular pantothenate for proliferation. The parasite converts pantothenate into coenzyme A (CoA) via five enzymes, the first being a pantothenate kinase (PfPanK). Multiple antiplasmodial pantothenate analogues, including pantothenol and CJ-15,801, kill the parasite by targeting CoA biosynthesis/utilisation. Their mechanism of action, however, remains unknown. Here, we show that parasites pressured with pantothenol or CJ-15,801 become resistant to these analogues. Whole-genome sequencing revealed mutations in one of two putative PanK genes (Pfpank1) in each resistant line. These mutations significantly alter PfPanK activity, with two conferring a fitness cost, consistent with Pfpank1 coding for a functional PanK that is essential for normal growth. The mutants exhibit a different sensitivity profile to recently-described, potent, antiplasmodial pantothenate analogues, with one line being hypersensitive. We provide evidence consistent with different pantothenate analogue classes having different mechanisms of action: some inhibit CoA biosynthesis while others inhibit CoA-utilising enzymes.

pharmacology and toxicology↗