Polarization of membrane associated proteins in the choroid plexus epithelium from normal and slc4a10 knockout mice

Christensen, Inga Baasch; Gyldenholm, Tua; Damkier, Helle Hasager; Prætorius, Jeppe

doi:10.3389/fphys.2013.00344

Cited by 24 publications

(32 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Genetic disruption of Ncbe resulted in a reduced volume of the brain ventricles, which was paralleled by the decrease in the Na + -dependent HCO 3 − uptake in CPECs [12]. We reported that the abundance and membrane targeting of various proteins in the CPECs were affected by Ncbe ko [13,15]. Here, we provide a comprehensive overview of the observed cellular differences within the CP following Ncbe deletion.…”

Section: Discussionmentioning

confidence: 83%

“…Notably, two of the most prominent luminal membrane proteins in CSF secretion were affected by the genetic slc4a10 disruption; we found reduced expression levels of the Na + ,K + -ATPase and the AQP1 to approximately 20% in the Ncbe ko mice, as compared to Ncbe wt mice [13]. The CPECs also displayed inversed localization of the Na + /H + exchanger NHE1 from the luminal side to the basolateral side in Ncbe ko [14] and further changes in cell polarity, cell contact and anchoring proteins [15]. Many of these changes would be consistent with a reduction of cellular secretory capacity.…”

Section: Introductionmentioning

confidence: 75%

“…Figure 5a shows the estimated mitochondrial area per cell as assessed by the cytochrome C immunofluorescence signal. The analysis revealed a decrease in cellular mitochondrial area to approximately 65% (p = 0.0073, n = Mean data for the IF semi-quantitation, except for NKCC1 are from previous publications [13][14][15] with a total of 482 Ncbe wt cells and 364 Ncbe ko cells assessed) in Ncbe ko CPECs compared to Ncbe wt CPECs. The cellular cytochrome C intensity in the Ncbe ko CPECs cells amounted to approximately 59% of the Ncbe wt values in the same analysis (Fig.…”

Section: The Cp Atp Level Is Elevated In Ncbe Ko Micementioning

confidence: 84%

“…Figure 2a-h shows immunoblot validation of the TMT 10-plex data for 5 transporters with decreasing abundance and 1 transporter with increased abundance along with proteasome 20 s loading controls (Ncbe p < 0.0001; AQP1, p = 0.0003; Na + ,K + -ATPase β1 p = 0.0055; Na + ,K + -ATPase α1 p = 0.0014; NKCC1 p = 0.059; Anion exchanger 2, Ae2, p = 0.0171; n = 5). Apart from NKCC1, immunofluorescence histochemistry was previously used to determine changes in the abundance of these transporters in the same mouse model [13][14][15]. Figure 2i, j show representative images used for semi-quantification illustrating reduced NKCC1 abundance in Ncbe ko vs. Ncbe wt CP.…”

Section: Changes In Transporter Abundance Indicate a Lower Secretory mentioning

confidence: 99%

See 3 more Smart Citations

Genetic disruption of slc4a10 alters the capacity for cellular metabolism and vectorial ion transport in the choroid plexus epithelium

Christensen

Bohlbro

et al. 2020

Fluids Barriers CNS

Self Cite

View full text Add to dashboard Cite

Background: Genetic disruption of slc4a10, which encodes the sodium-dependent chloride/bicarbonate exchanger Ncbe, leads to a major decrease in Na +-dependent HCO 3 − import into choroid plexus epithelial cells in mice and to a marked reduction in brain intraventricular fluid volume. This suggests that Ncbe functionally is a key element in vectorial Na + transport and thereby for cerebrospinal fluid secretion in the choroid plexus. However, slc4a10 disruption results in severe changes in expression of Na + ,K +-ATPase complexes and other major transport proteins, indicating that profound cellular changes accompany the genetic manipulation. Methods: A tandem mass tag labeling strategy was chosen for quantitative mass spectrometry. Alterations in the broader patterns of protein expression in the choroid plexus in response to genetic disruption of Ncbe was validated by semi-quantitative immunoblotting, immunohistochemistry and morphometry. Results: The abundance of 601 proteins were found significantly altered in the choroid plexus from Ncbe ko mice relative to Ncbe wt. In addition to a variety of transport proteins, particularly large changes in the abundance of proteins involved in cellular energy metabolism were detected in the Ncbe ko mice. In general, the abundance of rate limiting glycolytic enzymes and several mitochondrial enzymes were reduced following slc4a10 disruption. Surprisingly, this was accompanied by increased ATP levels in choroid plexus cells, indicating that the reduction in capacity for energy metabolism was adaptive to high ATP rather than causal for a decreased capacity for ion and water transport. Ncbedeficient cells also had a reduced cell area and decreased K + content. Conclusion: Our findings suggest that the lack of effective Na +-entry into the epithelial cells of the choroid plexus leads to a profound change in the cellular phenotype, shifting from a high-rate secretory function towards a more dormant state; similar to what is observed during ageing or Alzheimer's disease.

show abstract

Section: Discussionmentioning

confidence: 83%

Section: Introductionmentioning

confidence: 75%

Section: The Cp Atp Level Is Elevated In Ncbe Ko Micementioning

confidence: 84%

Section: Changes In Transporter Abundance Indicate a Lower Secretory mentioning

confidence: 99%

See 2 more Smart Citations

Genetic disruption of slc4a10 alters the capacity for cellular metabolism and vectorial ion transport in the choroid plexus epithelium

Christensen

Bohlbro

et al. 2020

Fluids Barriers CNS

Self Cite

View full text Add to dashboard Cite

show abstract

“…Semiquantitative analysis of immunofluorescence images were performed as described previously (Christensen et al . ).…”

Section: Methodsmentioning

confidence: 97%

The choroid plexus sodium‐bicarbonate cotransporter NBCe2 regulates mouse cerebrospinal fluid pH

Christensen

Barbuskaite

Rojek

et al. 2018

The Journal of Physiology

Self Cite

View full text Add to dashboard Cite

Key points Normal pH is crucial for proper functioning of the brain, and disorders increasing the level of CO2 in the blood lead to a decrease in brain pH.CO2 can easily cross the barriers of the brain and will activate chemoreceptors leading to an increased exhalation of CO2.The low pH, however, is harmful and bases such as HCO3 − are imported across the brain barriers in order to normalize brain pH.We show that the HCO3 − transporter NBCe2 in the choroid plexus of the blood‐cerebrospinal fluid barrier is absolutely necessary for normalizing CSF pH during high levels of CO2.This discovery represents a significant step in understanding the molecular mechanisms behind regulation of CSF pH during acid‐base disturbances, such as chronic lung disease. AbstractThe choroid plexus epithelium (CPE) is located in the brain ventricles where it produces the majority of the cerebrospinal fluid (CSF). The hypothesis that normal brain function is sustained by CPE‐mediated CSF pH regulation by extrusion of acid‐base equivalents was tested by determining the contribution of the electrogenic Na+‐HCO3 − cotransporter NBCe2 to CSF pH regulation. A novel strain of NBCe2 (Slc4a5) knockout (KO) mice was generated and validated. The base extrusion rate after intracellular alkalization was reduced by 77% in NBCe2 KO mouse CPE cells compared to control mice. NBCe2 KO mice and mice with CPE‐targeted NBCe2 siRNA knockdown displayed a reduction in CSF pH recovery during hypercapnia‐induced acidosis of approximately 85% and 90%, respectively, compared to control mice. NBCe2 KO did not affect baseline respiration rate or tidal volume, and the NBCe2 KO and wild‐type (WT) mice displayed similar ventilatory responses to 5% CO2 exposure. NBCe2 KO mice were not protected against pharmacological or heating‐induced seizure development. In conclusion, we establish the concept that the CPE is involved in the regulation of CSF pH by demonstrating that NBCe2 is necessary for proper CSF pH recovery after hypercapnia‐induced acidosis.

show abstract

Mechanisms of cerebrospinal fluid secretion by the choroid plexus epithelium: Application to various intracranial pathologies

Johnsen,

Friis,

Møller‐Madsen

et al. 2024

Clinical Anatomy

View full text Add to dashboard Cite

The choroid plexus (CP) is a small yet highly active epithelial tissue located in the ventricles of the brain. It secretes most of the CSF that envelops the brain and spinal cord. The epithelial cells of the CP have a high fluid secretion rate and differ from many other secretory epithelia in the organization of several key ion transporters. One striking difference is the luminal location of, for example, the vital Na+‐K+‐ATPase. In recent years, there has been a renewed focus on the role of ion transporters in CP secretion. Several studies have indicated that increased membrane transport activity is implicated in disorders such as hydrocephalus, idiopathic intracranial hypertension, and posthemorrhagic sequelae. The importance of the CP membrane transporters in regulating the composition of the CSF has also been a focus in research in recent years, particularly as a regulator of breathing and hemodynamic parameters such as blood pressure. This review focuses on the role of the fundamental ion transporters involved in CSF secretion and its ion composition. It gives a brief overview of the established factors and controversies concerning ion transporters, and finally discusses future perspectives related to the role of these transporters in the CP epithelium.

show abstract

Polarization of membrane associated proteins in the choroid plexus epithelium from normal and slc4a10 knockout mice

Cited by 24 publications

References 35 publications

Genetic disruption of slc4a10 alters the capacity for cellular metabolism and vectorial ion transport in the choroid plexus epithelium

Genetic disruption of slc4a10 alters the capacity for cellular metabolism and vectorial ion transport in the choroid plexus epithelium

The choroid plexus sodium‐bicarbonate cotransporter NBCe2 regulates mouse cerebrospinal fluid pH

Mechanisms of cerebrospinal fluid secretion by the choroid plexus epithelium: Application to various intracranial pathologies

Contact Info

Product

Resources

About