Limits...
The involvement of interleukin-22 in the expression of pancreatic beta cell regenerative Reg genes.

Hill T, Krougly O, Nikoopour E, Bellemore S, Lee-Chan E, Fouser LA, Hill DJ, Singh B - Cell Regen (Lond) (2013)

Bottom Line: This was associated with increased islet Regenerating (Reg) genes expression, and elevated IL-22-producing Th17 T-cells in the pancreas.Our results showed: 1) Reg1 and Reg2 mRNA abundance to be significantly increased in IL-22-treated islets in vitro; 2) IL-22 mRNA expression in the pre-diabetic mouse pancreas increased with time following CFA treatment; 3) a reduced expression of IL-22Rα following CFA treatment; 4) a down-regulation in Reg1 and Reg2 mRNA expression in the pancreas of pre-diabetic mice injected with an IL-22 neutralizing antibody; and 5) an increased islet β-cell DNA synthesis in vitro in the presence of IL-22.We conclude that IL-22 may contribute to the regeneration of β-cells by up-regulating Regenerating Reg1 and Reg2 genes in the islets.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology and Immunology, University of Western Ontario, London, ON Canada.

ABSTRACT

Background: In Type 1 diabetes, the insulin-producing β-cells within the pancreatic islets of Langerhans are destroyed. We showed previously that immunotherapy with Bacillus Calmette-Guerin (BCG) or complete Freund's adjuvant (CFA) of non-obese diabetic (NOD) mice can prevent disease process and pancreatic β-cell loss. This was associated with increased islet Regenerating (Reg) genes expression, and elevated IL-22-producing Th17 T-cells in the pancreas.

Results: We hypothesized that IL-22 was responsible for the increased Reg gene expression in the pancreas. We therefore quantified the Reg1, Reg2, and Reg3δ (INGAP) mRNA expression in isolated pre-diabetic NOD islets treated with IL-22. We measured IL-22, and IL-22 receptor(R)-α mRNA expression in the pancreas and spleen of pre-diabetic and diabetic NOD mice. Our results showed: 1) Reg1 and Reg2 mRNA abundance to be significantly increased in IL-22-treated islets in vitro; 2) IL-22 mRNA expression in the pre-diabetic mouse pancreas increased with time following CFA treatment; 3) a reduced expression of IL-22Rα following CFA treatment; 4) a down-regulation in Reg1 and Reg2 mRNA expression in the pancreas of pre-diabetic mice injected with an IL-22 neutralizing antibody; and 5) an increased islet β-cell DNA synthesis in vitro in the presence of IL-22.

Conclusions: We conclude that IL-22 may contribute to the regeneration of β-cells by up-regulating Regenerating Reg1 and Reg2 genes in the islets.

No MeSH data available.


Related in: MedlinePlus

Reg genes and IL-22 receptor(IL-22Rα) expression in the pancreatic islet cells after IL-22 treatment. Quantitative RT-PCR analysis was performed using gene-specific primers (Table 1) for Reg1, Reg2, Reg3δ and IL-22Rα on total RNA isolated from 6-week-old pancreatic islets (A-D). Islets were harvested 48 hrs after incubation with either DMEM medium (control); 10, or 50 ng/mL of recombinant IL-22; or a supernatant of Th17 cells polarized with IL-6 plus IL-23 (2 ml). Results shown represent the average fold-change in mRNA expression ± SEM when compared to control-treated islets. N = 3 mice (12 – 14 islets per mouse). Means indicated by the asterisk (*) are significantly different (P<0.05).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4230743&req=5

Fig1: Reg genes and IL-22 receptor(IL-22Rα) expression in the pancreatic islet cells after IL-22 treatment. Quantitative RT-PCR analysis was performed using gene-specific primers (Table 1) for Reg1, Reg2, Reg3δ and IL-22Rα on total RNA isolated from 6-week-old pancreatic islets (A-D). Islets were harvested 48 hrs after incubation with either DMEM medium (control); 10, or 50 ng/mL of recombinant IL-22; or a supernatant of Th17 cells polarized with IL-6 plus IL-23 (2 ml). Results shown represent the average fold-change in mRNA expression ± SEM when compared to control-treated islets. N = 3 mice (12 – 14 islets per mouse). Means indicated by the asterisk (*) are significantly different (P<0.05).

Mentions: To establish whether IL-22 induces Reg gene expression, 6-week-old pre-diabetic NOD mouse islets were isolated and incubated with recombinant IL-22 at 10 and 50 ng/mL concentrations or supernatants from Th17 polarized splenocytes containing IL-17 and IL-22 [15] (Figure 1). Quantitative RT-PCR was performed on total extracted RNA from the treated pancreatic islets. Reg2 and Reg1 mRNA levels were found to be significantly higher, by approximately 3 and 4.2-fold respectively, in islets incubated with 10 ng/mL of IL-22 when compared to the media control (P<0.05) (Figure 1A and 1B). Interestingly, the higher 50 ng/mL dose of IL-22 significantly down-regulated Reg2 and Reg1 expression (P<0.05). This was not due to the toxicity of the cytokine as there was no change in the viability of the treated islets cells as compared to media control. The highest fold increase in Reg2 gene expression was observed in islets treated with the supernatants of 4 days culture of BDC2.5 NOD splenocytes conditioned with IL-23 and IL-6 (Figure 1A). The supernatants also contained IL-22 and produced a significant 27-fold increase in Reg2 mRNA abundance when compared to the media control (P<0.05). Islets treated with the Th17 T cell supernatant also showed a significant up-regulation of Reg1 gene expression by approximately 4.3-fold, when compared to the control islets (P<0.05).However, unlike Reg2, this Reg1 expression was not significantly different when compared to islets treated with 10 ng/mL of recombinant IL-22. No significant change in Reg3δ expression was observed in response to IL-22 or the Th17 T cell supernatant (Figure 1C).Figure 1


The involvement of interleukin-22 in the expression of pancreatic beta cell regenerative Reg genes.

Hill T, Krougly O, Nikoopour E, Bellemore S, Lee-Chan E, Fouser LA, Hill DJ, Singh B - Cell Regen (Lond) (2013)

Reg genes and IL-22 receptor(IL-22Rα) expression in the pancreatic islet cells after IL-22 treatment. Quantitative RT-PCR analysis was performed using gene-specific primers (Table 1) for Reg1, Reg2, Reg3δ and IL-22Rα on total RNA isolated from 6-week-old pancreatic islets (A-D). Islets were harvested 48 hrs after incubation with either DMEM medium (control); 10, or 50 ng/mL of recombinant IL-22; or a supernatant of Th17 cells polarized with IL-6 plus IL-23 (2 ml). Results shown represent the average fold-change in mRNA expression ± SEM when compared to control-treated islets. N = 3 mice (12 – 14 islets per mouse). Means indicated by the asterisk (*) are significantly different (P<0.05).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4230743&req=5

Fig1: Reg genes and IL-22 receptor(IL-22Rα) expression in the pancreatic islet cells after IL-22 treatment. Quantitative RT-PCR analysis was performed using gene-specific primers (Table 1) for Reg1, Reg2, Reg3δ and IL-22Rα on total RNA isolated from 6-week-old pancreatic islets (A-D). Islets were harvested 48 hrs after incubation with either DMEM medium (control); 10, or 50 ng/mL of recombinant IL-22; or a supernatant of Th17 cells polarized with IL-6 plus IL-23 (2 ml). Results shown represent the average fold-change in mRNA expression ± SEM when compared to control-treated islets. N = 3 mice (12 – 14 islets per mouse). Means indicated by the asterisk (*) are significantly different (P<0.05).
Mentions: To establish whether IL-22 induces Reg gene expression, 6-week-old pre-diabetic NOD mouse islets were isolated and incubated with recombinant IL-22 at 10 and 50 ng/mL concentrations or supernatants from Th17 polarized splenocytes containing IL-17 and IL-22 [15] (Figure 1). Quantitative RT-PCR was performed on total extracted RNA from the treated pancreatic islets. Reg2 and Reg1 mRNA levels were found to be significantly higher, by approximately 3 and 4.2-fold respectively, in islets incubated with 10 ng/mL of IL-22 when compared to the media control (P<0.05) (Figure 1A and 1B). Interestingly, the higher 50 ng/mL dose of IL-22 significantly down-regulated Reg2 and Reg1 expression (P<0.05). This was not due to the toxicity of the cytokine as there was no change in the viability of the treated islets cells as compared to media control. The highest fold increase in Reg2 gene expression was observed in islets treated with the supernatants of 4 days culture of BDC2.5 NOD splenocytes conditioned with IL-23 and IL-6 (Figure 1A). The supernatants also contained IL-22 and produced a significant 27-fold increase in Reg2 mRNA abundance when compared to the media control (P<0.05). Islets treated with the Th17 T cell supernatant also showed a significant up-regulation of Reg1 gene expression by approximately 4.3-fold, when compared to the control islets (P<0.05).However, unlike Reg2, this Reg1 expression was not significantly different when compared to islets treated with 10 ng/mL of recombinant IL-22. No significant change in Reg3δ expression was observed in response to IL-22 or the Th17 T cell supernatant (Figure 1C).Figure 1

Bottom Line: This was associated with increased islet Regenerating (Reg) genes expression, and elevated IL-22-producing Th17 T-cells in the pancreas.Our results showed: 1) Reg1 and Reg2 mRNA abundance to be significantly increased in IL-22-treated islets in vitro; 2) IL-22 mRNA expression in the pre-diabetic mouse pancreas increased with time following CFA treatment; 3) a reduced expression of IL-22Rα following CFA treatment; 4) a down-regulation in Reg1 and Reg2 mRNA expression in the pancreas of pre-diabetic mice injected with an IL-22 neutralizing antibody; and 5) an increased islet β-cell DNA synthesis in vitro in the presence of IL-22.We conclude that IL-22 may contribute to the regeneration of β-cells by up-regulating Regenerating Reg1 and Reg2 genes in the islets.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology and Immunology, University of Western Ontario, London, ON Canada.

ABSTRACT

Background: In Type 1 diabetes, the insulin-producing β-cells within the pancreatic islets of Langerhans are destroyed. We showed previously that immunotherapy with Bacillus Calmette-Guerin (BCG) or complete Freund's adjuvant (CFA) of non-obese diabetic (NOD) mice can prevent disease process and pancreatic β-cell loss. This was associated with increased islet Regenerating (Reg) genes expression, and elevated IL-22-producing Th17 T-cells in the pancreas.

Results: We hypothesized that IL-22 was responsible for the increased Reg gene expression in the pancreas. We therefore quantified the Reg1, Reg2, and Reg3δ (INGAP) mRNA expression in isolated pre-diabetic NOD islets treated with IL-22. We measured IL-22, and IL-22 receptor(R)-α mRNA expression in the pancreas and spleen of pre-diabetic and diabetic NOD mice. Our results showed: 1) Reg1 and Reg2 mRNA abundance to be significantly increased in IL-22-treated islets in vitro; 2) IL-22 mRNA expression in the pre-diabetic mouse pancreas increased with time following CFA treatment; 3) a reduced expression of IL-22Rα following CFA treatment; 4) a down-regulation in Reg1 and Reg2 mRNA expression in the pancreas of pre-diabetic mice injected with an IL-22 neutralizing antibody; and 5) an increased islet β-cell DNA synthesis in vitro in the presence of IL-22.

Conclusions: We conclude that IL-22 may contribute to the regeneration of β-cells by up-regulating Regenerating Reg1 and Reg2 genes in the islets.

No MeSH data available.


Related in: MedlinePlus