Michael Helmrath · RAAS-deficient organoids indicate delayed angiogenesis as a possible cause for autosomal recessive renal tubular dysgenesis
Follow
Article1 min read·Published Dec 2023Older

RAAS-deficient organoids indicate delayed angiogenesis as a possible cause for autosomal recessive renal tubular dysgenesis

pubmed.ncbi.nlm.nih.gov shows its articles on its own site.

Read the article on pubmed.ncbi.nlm.nih.gov ↗

Article · Dec 2023 · 1 min read

In brief

In brief

This study uses kidney organoids derived from patient iPSCs to reveal that autosomal recessive renal tubular dysgenesis results from delayed angiogenesis rather than intrinsic tubular defects. Researchers demonstrate that insufficient VEGF-A expression in RAAS-deficient organoids prevents engraftment, but hypoxic conditions or ectopic VEGF-A rescue proximal tubule development, suggesting vascular insufficiency as the primary pathomechanism.

Written by the GCMD Library team from the article.

Michael Helmrath

Autosomal Recessive Renal Tubular Dysgenesis (AR-RTD) is a fatal genetic disorder characterized by complete absence or severe depletion of proximal tubules (PT) in patients harboring pathogenic variants in genes involved in the Renin-Angiotensin-Aldosterone System. To uncover the pathomechanism of AR-RTD, differentiation of ACE-/- and AGTR1-/- induced pluripotent stem cells (iPSCs) and AR-RTD patient-derived iPSCs into kidney organoids is leveraged. Comprehensive marker analyses show that both mutant and control organoids generate indistinguishable PT in vitro under normoxic (21% O2) or hypoxic (2% O2) conditions. Fully differentiated (d24) AGTR1-/- and control organoids transplanted under the kidney capsule of immunodeficient mice engraft and mature well, as do renal vesicle stage (d14) control organoids. By contrast, d14 AGTR1-/- organoids fail to engraft due to insufficient pro-angiogenic VEGF-A expression. Notably, growth under hypoxic conditions induces VEGF-A expression and rescues engraftment of AGTR1-/- organoids at d14, as does ectopic expression of VEGF-A. We propose that PT dysgenesis in AR-RTD is primarily a non-autonomous consequence of delayed angiogenesis, starving PT at a critical time in their development.

Statements in this article

  1. Autosomal recessive renal tubular dysgenesis is a fatal genetic disorder characterized by complete absence or severe depletion of proximal tubules in patients with pathogenic variants in genes involved in the renin-angiotensin-aldosterone system.

    Established
  2. ACE-/- and AGTR1-/- mutant organoids and control organoids generate indistinguishable proximal tubules in vitro under normoxic (21% O2) or hypoxic (2% O2) conditions.

    Research
  3. Fully differentiated day 24 AGTR1-/- and control organoids transplanted under the kidney capsule of immunodeficient mice engraft and mature well.

    Research
  4. Renal vesicle stage day 14 control organoids engraft well when transplanted under the kidney capsule.

    Research
  5. Day 14 AGTR1-/- organoids fail to engraft due to insufficient pro-angiogenic VEGF-A expression.

    Research
  6. Growth under hypoxic conditions induces VEGF-A expression and rescues engraftment of AGTR1-/- organoids at day 14.

    Research
  7. Ectopic expression of VEGF-A rescues engraftment of day 14 AGTR1-/- organoids.

    Research
  8. Proximal tubule dysgenesis in autosomal recessive renal tubular dysgenesis is primarily a non-autonomous consequence of delayed angiogenesis that starves proximal tubules at a critical time in their development.

    Research

Read it at the source ↗

Try
Intelligent Search· scoped to this article · not medical adviceSearch the whole library →