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Made available in DSpace on 2019-10-04T12:42:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-08-05 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) In this study, we evaluated the modulation effect of long-chain Acyl-CoA synthetase during early embryo development. Bovine embryos were cultured in four groups: positive modulation (ACS+) with GW3965 hydrochloride, negative modulation (ACS-) with Triacsin C, association of both modulators (ACS +/-), and control. Embryo development rates were not altered (P>0.05) by treatments. Embryonic cytoplasmic lipid content increased in ACS+ but reduced in ACS- compared to the control (P < 0.05), whereas the membrane phospholipids profile was not altered by treatments. The total number of blastomeres did not differ (P > 0.05) between groups; however, an increased apoptotic cells percentage was found in ACS- compared to control. Twenty-four hours after warming, ACS+ and control grade I embryos presented the best hatching rates, whereas the ACS+ group equaled the hatching rates between their embryos of grades I, II and III 48 hours after warming. The relative abundance of transcripts for genes associated with lipid metabolism (ACSL3, ACSL6, ACAT1, SCD, and AUH), heatshock (HSP90AA1 and HSF1), oxidative stress (GPX4), and angiogenesis (VEGF), among other important genes for embryo development were affected by at least one of the treatments. The treatments were effective in modulating the level of transcripts for ACSL3 and the cytoplasmic lipid content. The ACS- was not effective in increasing embryonic cryosurvival, whereas ACS+ restored survival rates after vitrification of embryos with low quality, making them equivalent to embryos of excellent quality. Fed Univ Pampa, Sch Vet Med, Uruguaiana, RS, Brazil Fed Univ ABC, Ctr Nat & Human Sci, Santo Andre, SP, Brazil Univ Sao Paulo, Dept Anim Reprod, Sao Paulo, SP, Brazil ABS Pecplan, In Vitro Brasil, Mogi Mirim, SP, Brazil Univ Fed Uberlandia, Dept Chem, Uberlandia, MG, Brazil Univ Prebiteriana Mackenzie, Sch Engn, Sao Paulo, SP, Brazil Sao Paulo State Univ, Dept Anim Reprod, Botucatu, SP, Brazil Sao Paulo State Univ, Dept Biol Sci, Assis, SP, Brazil Sao Paulo State Univ, Dept Anim Reprod, Botucatu, SP, Brazil Sao Paulo State Univ, Dept Biol Sci, Assis, SP, Brazil CAPES: 1 CAPES: 2012/50533-2 CAPES: 2019/16239-9

Subject Areas: carotid arteries; emulsions; fatty acids; gene expression; heparin; hypothalamus; neurons; oxidation.; International audience; Variations in plasma fatty acid (FA) concentrations are detected by FA sensing neurons in specific brain areas such as the hypothalamus. These neurons play a physiological role in the control of food intake and the regulation of hepatic glucose production. Le Foll et al. previously showed in vitro that at least 50% of the FA sensing in ventromedial hypothalamic (VMH) neurons is attributable to the interaction of long chain FA with FA translocase/CD36 (CD36). The present work assessed whether in vivo effects of hypothalamic FA sensing might be partly mediated by CD36 or intracellular events such as acylCoA synthesis or β-oxidation. To that end, a catheter was implanted in the carotid artery toward the brain in male Wistar rats. After 1 wk recovery, animals were food-deprived for 5 h, then 10 min infusions of triglyceride emulsion, Intralipid +/- heparin (IL, ILH, respectively) or saline/heparin (SH) were carried out and food intake was assessed over the next 5 h. Experimental groups included: 1) Rats previously injected in ventromedian nucleus (VMN) with shRNA against CD36 or scrambled RNA; 2) Etomoxir (CPT1 inhibitor) or saline co-infused with ILH/SH; and 3) Triacsin C (acylCoA synthase inhibitor) or saline co-infused with ILH/SH. ILH significantly lowered food intake during refeeding compared to SH (p

The role of the free fatty acid (FFA) receptor and the intracellular metabolites of linoleic acid (LA) in LA-stimulated increase in cytosolic free calcium concentration ([Ca(2+)]i) was investigated. [Ca(2+)]i was measured using Fura-2 as indicator in rat pancreatic β-cells in primary culture. LA (20 µM for 2 min) stimulated a transient peak increase followed by a minor plateau increase in [Ca(2+)]i. Elongation of LA stimulation up to 10 min induced a strong and long-lasting elevation in [Ca(2+)]i. Activation of FFA receptors by the non-metabolic agonist GW9508 (40 µM for 10 min) resulted in an increase in [Ca(2+)]i similar to that of 2-min LA treatment. Inhibition of acyl-CoA synthetases by Triacsin C suppressed the strong and long-lasting increase in [Ca(2+)]i. The increase in [Ca(2+)]i induced by 2 min LA or GW9508 were fully eliminated by exhaustion of endoplasmic reticulum (ER) Ca(2+) stores or by inhibition of phospholipase C (PLC). Removal of extracellular Ca(2+) did not influence the transient peak increase in [Ca(2+)]i stimulated by 2 min LA or GW9508. The strong and long-lasting increase in [Ca(2+)]i induced by 10 min LA was only partially suppressed by extracellular Ca(2+) removal or thapsigargin pretreatment, whereas remaining elevation in [Ca(2+)]i was eliminated after exhaustion of mitochondrial Ca(2+) using triphenyltin. In conclusion, LA stimulates Ca(2+) release from ER through activation of the FFA receptor coupled to PLC and mobilizes mitochondrial Ca(2+) by intracellular metabolites in β-cells.