Pereira Patricia Marques, Papy-Garcia Dulce, Barritault Denis, Chiappini Franck, Jackisch Rolf, Schimchowitsch Sarah, Cassel Jean-Christophe
UMR 7364 LNCA, Université de Strasbourg, 12 rue Goethe, F-67000, Strasbourg, France.
Glycobiology, cell growth and tissue repair research unit (Gly- CRRET), Univ Paris Est Créteil (UPEC), F-94010, Créteil, France.
Glycoconj J. 2022 Feb;39(1):107-130. doi: 10.1007/s10719-022-10047-x. Epub 2022 Mar 7.
Using a partial hippocampal cholinergic denervation model, we assessed the effects of the RGTA named OTR4132, a synthetic heparan-mimetic biopolymer with neuroprotective/neurotrophic properties. Long-Evans male rats were injected with the cholinergic immunotoxin 192 IgG-saporin into the medial septum/diagonal band of Broca (0.37 µg); vehicle injections served as controls. Immediately after surgery, OTR4132 was injected into the lateral ventricles (0.25 µg/5 µl/rat) or intramuscularly (1.5 mg/kg). To determine whether OTR4132 reached the lesion site, some rats received intracerebroventricular (ICV) or intramuscular (I.M.) injections of fluorescent OTR4132. Rats were sacrificed at 4, 10, 20, or 60 days post-lesion (DPL). Fluorescein-labeled OTR4132 injected ICV or I.M. was found in the lesion from 4 to 20 DPL. Rats with partial hippocampal cholinergic denervation showed decreases in hippocampal acetylcholinesterase reaction products and in choline acetyltransferase-positive neurons in the medial septum. These lesions were the largest at 10 DPL and then remained stable until 60 DPL. Both hippocampal acetylcholinesterase reaction products and choline acetyltransferase-positive neurons in the medial septum effects were significantly attenuated in OTR4132-treated rats. These effects were not related to competition between OTR4132 and 192 IgG-saporin for the neurotrophin receptor P75 (p75), as OTR4132 treatment did not alter the internalization of Cy3-labelled 192 IgG. OTR4132 was more efficient at reducing the acetylcholinesterase reaction products and choline acetyltransferase-positive neurons than a comparable heparin dose used as a comparator. Using the slice superfusion technique, we found that the lesion-induced decrease in muscarinic autoreceptor sensitivity was abolished by intramuscular OTR4132. After partial cholinergic damage, OTR4132 was able to concentrate at the brain lesion site possibly due to the disruption of the blood-brain barrier and to exert structural and functional effects that hold promises for neuroprotection/neurotrophism.
利用部分海马胆碱能去神经支配模型，我们评估了名为OTR4132的RGTA的作用，OTR4132是一种具有神经保护/神经营养特性的合成类肝素生物聚合物。将雄性Long-Evans大鼠的内侧隔区/布罗卡斜角带注射胆碱能免疫毒素192 IgG-皂草素（0.37微克）；注射赋形剂作为对照。手术后立即将OTR4132注射到侧脑室（0.25微克/5微升/只大鼠）或肌肉内（1.5毫克/千克）。为了确定OTR4132是否到达损伤部位，一些大鼠接受了脑室内（ICV）或肌肉内（I.M.）注射荧光标记的OTR4132。在损伤后4、10、20或60天处死大鼠。在损伤后4至20天，在损伤部位发现了脑室内或肌肉内注射的荧光素标记的OTR4132。部分海马胆碱能去神经支配的大鼠海马乙酰胆碱酯酶反应产物和内侧隔区胆碱乙酰转移酶阳性神经元减少。这些损伤在损伤后10天最大，然后一直稳定到损伤后60天。在接受OTR4132治疗的大鼠中，海马乙酰胆碱酯酶反应产物和内侧隔区胆碱乙酰转移酶阳性神经元的影响均显著减弱。这些作用与OTR4132和192 IgG-皂草素对神经营养因子受体P75（p75）的竞争无关，因为OTR4132治疗并未改变Cy3标记的192 IgG的内化。与用作对照的同等剂量肝素相比，OTR4132在减少乙酰胆碱酯酶反应产物和胆碱乙酰转移酶阳性神经元方面更有效。使用脑片灌流技术，我们发现肌肉注射OTR4132可消除损伤诱导的毒蕈碱自身受体敏感性降低。部分胆碱能损伤后，OTR4132可能由于血脑屏障的破坏而能够在脑损伤部位聚集，并发挥具有神经保护/神经营养前景的结构和功能作用。
