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Metabolic Coupling Determines the Activity: Comparison of 11β-Hydroxysteroid Dehydrogenase 1 and Its Coupling between Liver Parenchymal Cells and Testicular Leydig Cells.

Li X, Hu G, Li X, Wang YY, Hu YY, Zhou H, Latif SA, Morris DJ, Chu Y, Zheng Z, Ge RS - PLoS ONE (2015)

Bottom Line: S3483, a G6P transporter inhibitor, reversed the G6P-mediated increases of 11β-HSD1 reductase activity.The depletion of Leydig cells eliminated Hsd11b1 (encoding 11β-HSD1) expression but did not affect the expression of H6pd (encoding H6PDH) and Slc37a4 (encoding G6P transporter).In conclusion, the availability of H6PDH determines the different direction of 11β-HSD1 in liver and Leydig cells.

View Article: PubMed Central - PubMed

Affiliation: The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, ZJ 325000, PR China.

ABSTRACT

Background: 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) interconverts active 11β-hydroxyl glucocorticoids and inactive 11keto forms. However, its directionality is determined by availability of NADP+/NADPH. In liver cells, 11β-HSD1 behaves as a primary reductase, while in Leydig cells it acts as a primary oxidase. However, the exact mechanism is not clear. The direction of 11β-HSD1 has been proposed to be regulated by hexose-6-phosphate dehydrogenase (H6PDH), which catalyzes glucose-6-phosphate (G6P) to generate NADPH that drives 11β-HSD1 towards reduction.

Methodology: To examine the coupling between 11β-HSD1 and H6PDH, we added G6P to rat and human liver and testis or Leydig cell microsomes, and 11β-HSD1 activity was measured by radiometry.

Results and conclusions: G6P stimulated 11β-HSD1 reductase activity in rat (3 fold) or human liver (1.5 fold), but not at all in testis. S3483, a G6P transporter inhibitor, reversed the G6P-mediated increases of 11β-HSD1 reductase activity. We compared the extent to which 11β-HSD1 in rat Leydig and liver cells might be coupled to H6PDH. In order to clarify the location of H6PDH within the testis, we used the Leydig cell toxicant ethane dimethanesulfonate (EDS) to selectively deplete Leydig cells. The depletion of Leydig cells eliminated Hsd11b1 (encoding 11β-HSD1) expression but did not affect the expression of H6pd (encoding H6PDH) and Slc37a4 (encoding G6P transporter). H6pd mRNA level and H6PDH activity were barely detectable in purified rat Leydig cells. In conclusion, the availability of H6PDH determines the different direction of 11β-HSD1 in liver and Leydig cells.

No MeSH data available.


Related in: MedlinePlus

Real-time PCR analysis of Hsd3b1, Hsd11b1, Hsd11b2, H6pd, and Slc37a4 in the testis at different days after EDS treatment.Mean ± SEM, n = 4~6. Identical letters designate that there were no significant differences between two groups at P < 0.05.
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pone.0141767.g004: Real-time PCR analysis of Hsd3b1, Hsd11b1, Hsd11b2, H6pd, and Slc37a4 in the testis at different days after EDS treatment.Mean ± SEM, n = 4~6. Identical letters designate that there were no significant differences between two groups at P < 0.05.

Mentions: In order to detect the relative levels of Hsd11b1 (encoding 11β-HSD1), Hsd11b2 (encoding 11β-HSD2), H6pd (encoding H6PDH) and Slc37a4 (encoding G6P transporter) in rat Leydig cells, an EDS-treated rat model, in which EDS specifically eliminates only Leydig cells [13], was used. Seven days post EDS, all Leydig cells were eliminated, as shown that there was undetectable Hsd3b1 expression (Fig 4A). By 35 days post EDS, Leydig cell regeneration is in progress as shown by the Hsd3b1 expression (Fig 4A). In this model, the presence of Leydig cell specific enzymes coincides closely with the absence or presence of Leydig cells.


Metabolic Coupling Determines the Activity: Comparison of 11β-Hydroxysteroid Dehydrogenase 1 and Its Coupling between Liver Parenchymal Cells and Testicular Leydig Cells.

Li X, Hu G, Li X, Wang YY, Hu YY, Zhou H, Latif SA, Morris DJ, Chu Y, Zheng Z, Ge RS - PLoS ONE (2015)

Real-time PCR analysis of Hsd3b1, Hsd11b1, Hsd11b2, H6pd, and Slc37a4 in the testis at different days after EDS treatment.Mean ± SEM, n = 4~6. Identical letters designate that there were no significant differences between two groups at P < 0.05.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4631333&req=5

pone.0141767.g004: Real-time PCR analysis of Hsd3b1, Hsd11b1, Hsd11b2, H6pd, and Slc37a4 in the testis at different days after EDS treatment.Mean ± SEM, n = 4~6. Identical letters designate that there were no significant differences between two groups at P < 0.05.
Mentions: In order to detect the relative levels of Hsd11b1 (encoding 11β-HSD1), Hsd11b2 (encoding 11β-HSD2), H6pd (encoding H6PDH) and Slc37a4 (encoding G6P transporter) in rat Leydig cells, an EDS-treated rat model, in which EDS specifically eliminates only Leydig cells [13], was used. Seven days post EDS, all Leydig cells were eliminated, as shown that there was undetectable Hsd3b1 expression (Fig 4A). By 35 days post EDS, Leydig cell regeneration is in progress as shown by the Hsd3b1 expression (Fig 4A). In this model, the presence of Leydig cell specific enzymes coincides closely with the absence or presence of Leydig cells.

Bottom Line: S3483, a G6P transporter inhibitor, reversed the G6P-mediated increases of 11β-HSD1 reductase activity.The depletion of Leydig cells eliminated Hsd11b1 (encoding 11β-HSD1) expression but did not affect the expression of H6pd (encoding H6PDH) and Slc37a4 (encoding G6P transporter).In conclusion, the availability of H6PDH determines the different direction of 11β-HSD1 in liver and Leydig cells.

View Article: PubMed Central - PubMed

Affiliation: The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, ZJ 325000, PR China.

ABSTRACT

Background: 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) interconverts active 11β-hydroxyl glucocorticoids and inactive 11keto forms. However, its directionality is determined by availability of NADP+/NADPH. In liver cells, 11β-HSD1 behaves as a primary reductase, while in Leydig cells it acts as a primary oxidase. However, the exact mechanism is not clear. The direction of 11β-HSD1 has been proposed to be regulated by hexose-6-phosphate dehydrogenase (H6PDH), which catalyzes glucose-6-phosphate (G6P) to generate NADPH that drives 11β-HSD1 towards reduction.

Methodology: To examine the coupling between 11β-HSD1 and H6PDH, we added G6P to rat and human liver and testis or Leydig cell microsomes, and 11β-HSD1 activity was measured by radiometry.

Results and conclusions: G6P stimulated 11β-HSD1 reductase activity in rat (3 fold) or human liver (1.5 fold), but not at all in testis. S3483, a G6P transporter inhibitor, reversed the G6P-mediated increases of 11β-HSD1 reductase activity. We compared the extent to which 11β-HSD1 in rat Leydig and liver cells might be coupled to H6PDH. In order to clarify the location of H6PDH within the testis, we used the Leydig cell toxicant ethane dimethanesulfonate (EDS) to selectively deplete Leydig cells. The depletion of Leydig cells eliminated Hsd11b1 (encoding 11β-HSD1) expression but did not affect the expression of H6pd (encoding H6PDH) and Slc37a4 (encoding G6P transporter). H6pd mRNA level and H6PDH activity were barely detectable in purified rat Leydig cells. In conclusion, the availability of H6PDH determines the different direction of 11β-HSD1 in liver and Leydig cells.

No MeSH data available.


Related in: MedlinePlus