The aim of the work was to obtain data and formulate knowledge about the behavioural manifestations of dairy cows in relation to the management system of feeding regime on the farm, where Holstein ...cows are bred. The observations took place on the 13 and 14 August, 2014, when the cows were observed for 24 hours continuously. The ethogram records were recorded after 1 minute and physical activity of cows, periods of rest, ruminating, eating, drinking, defecation, urination and comfort and social behaviour. Cows are herded for milking 3 times a day. It was found that within 24 hours dairy cows spend on average 10 hours by lying, 8 hours by ruminating, 20 minutes by drinking, 6 hours by eating, they defecate 14 times, urinate 6 times and walk about 430 meters. They are also scratching, licking each other and tail swiping (comfort behaviour) within 24 hours. The observations of the responses to serving food indicate that cows actively react to the passage of the food vehicle, not the passage of a piling-up tractor.
A thus far untested approach is targeting mitochondrial respiration using compounds from the group of mitocans,3 epitomised by mitochondrially targeted tamoxifen (MitoTam), that is, tamoxifen tagged ...with the mitochondrial vector triphenylphosphonium (TPP) (Figure S1A; see also Supporting Information for description of synthesis).4,5 This strategy is based on the premise that cancer cells differ from their non-cancerous counterparts,3 making them selectively vulnerable to TPP-tagged anti-cancer agents,6 and on the premise that mitochondrial function is vital for tumour progression.7,8 We have recently conducted Phase 1/1b MitoTam clinical trial for metastatic solid tumour patients, with all patients undergoing palliative therapy after exhaustion of established therapeutic regimens (MitoTam-01 trial; EudraCT 2017-004441-25). SEE PDF As renal cancer cells possess high activity of oxidative phosphorylation (OXPHOS) and its inhibition induces cell death in starvation-resistant tumours,7 we studied the effect of MitoTam on renal cancer in vitro and in vivo to better understand its benefit for patients. Despite promising results of immunotherapy, resistance to this treatment occurs in several tumour types providing an opportunity for improved immunotherapeutic approaches. Since targeting of immune checkpoints (ICIs) PD-L1 and PD-1, currently representing first-line therapy in renal cancer,9 induces metabolic reprogramming of cancer cells by decreased ability to use glycolysis and increased OXPHOS importance,10 we combined their effect with MitoTam. PD-L1 treatment enhanced infiltration and activity of CD8+ T-cells, which was not affected by MitoTam (Figure 4D–F). ...MitoTam affected the level of PD-L1 neither in tumours of mice with syngeneic carcinomas (Figure 4G) nor in the two cancer patients presented in Figure 1A (Figure S4E).
Mitochondrial oxidative phosphorylation (OXPHOS) generates ATP, but OXPHOS also supports biosynthesis during proliferation. In contrast, the role of OXPHOS during quiescence, beyond ATP production, ...is not well understood. Using mouse models of inducible OXPHOS deficiency in all cell types or specifically in the vascular endothelium that negligibly relies on OXPHOS-derived ATP, we show that selectively during quiescence OXPHOS provides oxidative stress resistance by supporting macroautophagy/autophagy. Mechanistically, OXPHOS constitutively generates low levels of endogenous ROS that induce autophagy via attenuation of ATG4B activity, which provides protection from ROS insult. Physiologically, the OXPHOS-autophagy system (i) protects healthy tissue from toxicity of ROS-based anticancer therapy, and (ii) provides ROS resistance in the endothelium, ameliorating systemic LPS-induced inflammation as well as inflammatory bowel disease. Hence, cells acquired mitochondria during evolution to profit from oxidative metabolism, but also built in an autophagy-based ROS-induced protective mechanism to guard against oxidative stress associated with OXPHOS function during quiescence.
Abbreviations: AMPK: AMP-activated protein kinase; AOX: alternative oxidase; Baf A: bafilomycin A
1
; CI, respiratory complexes I; DCF-DA: 2′,7′-dichlordihydrofluorescein diacetate; DHE: dihydroethidium; DSS: dextran sodium sulfate; ΔΨmi: mitochondrial inner membrane potential; EdU: 5-ethynyl-2'-deoxyuridine; ETC: electron transport chain; FA: formaldehyde; HUVEC; human umbilical cord endothelial cells; IBD: inflammatory bowel disease; LC3B: microtubule associated protein 1 light chain 3 beta; LPS: lipopolysaccharide; MEFs: mouse embryonic fibroblasts; MTORC1: mechanistic target of rapamycin kinase complex 1; mtDNA: mitochondrial DNA; NAC: N-acetyl cysteine; OXPHOS: oxidative phosphorylation; PCs: proliferating cells; PE: phosphatidylethanolamine; PEITC: phenethyl isothiocyanate; QCs: quiescent cells; ROS: reactive oxygen species; PLA2: phospholipase A2, WB: western blot.
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