The Iron-Klotho-VDR Axis Is a Major Determinant of Proximal Convoluted Tubule Injury in Haptoglobin 2-2 Genotype Diabetic Nephropathy Patients and Mice

<div>Renal vitamin D receptor (VDR) expression in nondiabetic (nonDM) and diabetic (DN) mice. (a) Renal sections from Hp 1-1 and 2-2 mice were subjected to IHC of VDR (brown, indicated by arrowheads). (b) There was a significant decrease in the percentage of the VDR-stained area in the tubules of Hp 2-2 DM renal sections compared with Hp 1-1 DM (<svg height="13.532pt" id="M28" style="vertical-align:-3.4295pt" version="1.1" viewbox="-0.0498162 -10.1025 50.6052 13.532" width="50.6052pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M486 158C486 177 478 202 466 220C413 228 386 236 336 262C386 288 413 297 466 304C478 323 486 347 485 366C470 376 444 381 422 380C389 338 368 319 321 288C323 345 329 372 349 422C339 442 322 461 305 470C289 461 271 442 262 422C281 372 287 345 290 288C243 319 222 338 189 380C167 381 142 376 125 366C125 347 133 322 145 304C198 296 225 288 275 262C225 236 198 227 145 220C133 201 125 177 126 158C141 148 167 143 189 144C222 186 243 205 290 236C288 179 282 152 262 102C272 82 289 63 306 54C322 63 340 82 350 102C330 152 324 179 321 236C368 205 390 186 422 144C444 143 470 148 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(c) Western blot analysis of VDR with the mice renal lysate. Proteins were detected by immunoblotting with antibodies against VDR and GAPDH. The values represent the mean ± SEM for 3 independent experiments subjected to 2-tailed, 2-sampled unequal variance Student’s <i>t</i>-test, with <svg height="13.532pt" id="M30" style="vertical-align:-3.4295pt" version="1.1" viewbox="-0.0498162 -10.1025 56.8686 13.532" width="56.8686pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M486 158C486 177 478 202 466 220C413 228 386 236 336 262C386 288 413 297 466 304C478 323 486 347 485 366C470 376 444 381 422 380C389 338 368 319 321 288C323 345 329 372 349 422C339 442 322 461 305 470C289 461 271 442 262 422C281 372 287 345 290 288C243 319 222 338 189 380C167 381 142 376 125 366C125 347 133 322 145 304C198 296 225 288 275 262C225 236 198 227 145 220C133 201 125 177 126 158C141 148 167 143 189 144C222 186 243 205 290 236C288 179 282 152 262 102C272 82 289 63 306 54C322 63 340 82 350 102C330 152 324 179 321 236C368 205 390 186 422 144C444 143 470 148 486 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id="M31" style="vertical-align:-3.429399pt" version="1.1" viewbox="-0.0498162 -11.5275 55.736 14.9569" width="55.736pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M457 455H370L403 612H360L326 455H218L252 612H210L175 455H77L68 394H161L132 257H31L20 196H117L77 19H120L159 196H268L230 19H272L311 196H402L412 257H325L355 394H447L457 455ZM313 394L283 257H175L204 394H313Z" id="g58-33"></path></g><g transform="matrix(.013,0,0,-0.013,4.946,0)"><path d="M570 304C570 398 525 448 414 448C385 448 343 445 312 434L329 511L321 518C297 504 262 482 244 460L233 411C195 397 159 381 128 358L135 332C160 347 189 360 224 373L111 -147C97 -210 84 -218 17 -231L13 -257L254 -247L259 -218L233 -216C183 -212 177 -202 189 -142L218 -1C238 -10 266 -12 283 -12C351 3 429 48 483 105C543 168 570 242 570 304ZM482 289C482 161 380 33 304 33C278 33 248 51 233 69L303 396C326 400 352 403 369 403C428 403 482 380 482 289Z" 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AU: arbitrary units.</div>

Journal of Diabetes Research

fig5

Figure 5

Figure 5: The Iron-Klotho-VDR Axis Is a Major Determinant of Proximal Convoluted Tubule Injury in Haptoglobin 2-2 Genotype Diabetic Nephropathy Patients and Mice 

Figure 5 | The Iron-Klotho-VDR Axis Is a Major Determinant of Proximal Convoluted Tubule Injury in Haptoglobin 2-2 Genotype Diabetic Nephropathy Patients and Mice 