PI3K/Akt and ERK1/2 Signalling Are Involved in Quercetin-Mediated Neuroprotection against Copper-Induced Injury

<div>Effects of wortmannin and UO126 against the neuroprotective action of quercetin in moderately injured P19 neurons. P19 neurons were treated with 30 nM wortmannin and 10 <i>μ</i>M UO126 for 1 h prior to and during the treatment with 0.5 mM CuSO<sub>4</sub>. At 24 h from the beginning of treatment with copper and quercetin, the survival of P19 neurons was determined by MTT assay. Exposure to both wortmannin (a) and UO126 (b) prevented the beneficial effects of quercetin on neuronal survival in copper-induced oxidative stress conditions. Values are expressed as <svg height="9.10327pt" id="M44" style="vertical-align:-0.3499298pt" version="1.1" viewbox="-0.0498162 -8.75334 62.8814 9.10327" width="62.8814pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M797 0V26C739 32 732 36 732 103V296C732 394 682 449 605 449C576 449 550 437 529 423C504 407 475 389 446 366C425 418 382 449 334 449C303 449 279 437 253 421C222 403 201 385 180 371V452C135 432 85 419 41 411V388C99 379 102 374 102 310V103C102 38 93 32 27 26V0H238V26C189 32 180 38 180 103V338C210 363 250 390 289 390C351 390 377 348 377 275V103C377 37 368 32 306 26V0H520V26C465 32 456 38 456 101V296C456 314 455 326 453 338C491 369 529 390 565 390C628 390 653 345 653 274V107C653 36 642 32 583 26V0H797Z"></path></g><g transform="matrix(.013,0,0,-0.013,10.595,0)"><path d="M380 106C343 72 306 56 265 56C195 56 116 112 115 248C235 252 361 262 377 265C396 269 400 277 400 297C400 374 333 449 250 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-7 175 -15 216 -15C349 -15 438 69 438 174C438 287 344 333 265 374C186 414 138 449 138 522C138 576 172 631 249 631C336 631 363 562 380 499L409 504Z"></path></g><g transform="matrix(.013,0,0,-0.013,53.139,0)"><path d="M43 650V622C120 616 128 612 128 526V124C128 39 120 33 34 27V0H270C392 0 492 25 567 83C643 141 690 230 690 350C690 444 655 517 605 565C543 625 450 650 323 650H43ZM213 547C213 587 217 598 226 604C236 612 262 617 304 617C371 617 429 604 474 576C554 529 592 439 592 336C592 176 505 36 319 36C246 36 213 55 213 131V547Z"></path></g></svg> from five independent experiments performed in quadruplets. <sup>a</sup><svg height="9.2729pt" id="M45" style="vertical-align:-0.6370001pt" version="1.1" viewbox="-0.0498162 -8.6359 44.8393 9.2729" width="44.8393pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M600 480C600 590 528 650 384 650H143L137 622C222 614 225 607 210 531L130 127C113 41 106 36 23 28L17 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109 583V559L157 557C201 555 205 550 205 499V114C205 42 199 34 109 27V0H384Z"></path></g></svg> vs. the copper- or the copper- and quercetin-treated group (one-way ANOVA followed by post hoc Tukey’s test).</div>

Oxidative Medicine and Cellular Longevity

fig6

Figure 6

Figure 6: PI3K/Akt and ERK1/2 Signalling Are Involved in Quercetin-Mediated Neuroprotection against Copper-Induced Injury 