Figure 1.
Biochemical characterization of C57BL/6J Slc30a8 KO mice.
Panel A: Immunohistochemical staining of wild type and Slc30a8 KO mouse pancreas with antisera raised to insulin, glucagon, and ZnT-8 was performed as described in Materials and Methods. Representative pictures are shown. WT, wild type; KO, knockout. Panel B: Zinc content in isolated islets was determined as described in Material and Methods. Results represent the mean ± S.E.M. (n = 3 independent islet preparations for each genotype with each islet preparation assayed in quintuplicate). *p<0.05 versus WT.
Figure 2.
Analysis of glucose tolerance in male C57BL/6J Slc30a8 KO mice in vivo.
Intraperitoneal (Panels A and C) and oral (Panel B) glucose tolerance tests were performed on 6 hr fasted conscious C57BL/6J WT (closed symbols) and Slc30a8 KO (open symbols) male mice as described in Materials and Methods. The IPGTT results in Panel A show the mean glucose concentrations ± S.E.M. in WT (n = 11; mean age ∼20 weeks) and Slc30a8 KO (n = 9; mean age ∼20 weeks) animals. The OGTT results in Panel B show the mean glucose concentrations ± S.E.M. in WT (n = 16; mean age ∼22 weeks) and Slc30a8 KO (n = 9; mean age ∼22 weeks) animals. The IPGTT results in Panel C show the mean glucose concentrations ± S.E.M. in WT (n = 17; mean age ∼4 weeks) and Slc30a8 KO (n = 19; mean age ∼4 weeks) animals. *p<0.05 versus WT.
Table 1.
Phenotypic characterization of fasted C57BL/6J Slc30a8 KO mice.
Figure 3.
Analysis of insulin content and glucose-stimulated insulin secretion in male C57BL/6J Slc30a8 KO mouse islets in situ.
Islets were isolated from male C57BL/6J WT and Slc30a8 KO mice and then insulin content (Panel A) and glucose-stimulated insulin secretion (Panel B) were assayed as described in Materials and Methods. Results show the mean data ± S.E.M. from 3 islet preparations isolated from ∼18 week old male mice. *p<0.05 versus 5 mM glucose.
Figure 4.
Phenotypic characterization of high fat fed male C57BL/6J Slc30a8 KO mice.
Male WT (n = 5; mean age 44.6 weeks), heterozygous (HET) (n = 14; mean age 39.6 weeks) and KO (n = 6; mean age 49.5 weeks) mice were fed a high fat diet with body weights measured weekly (Panel A). After 8 weeks mice fasted for 4 hours and then weighed. One hour later mice were anesthetized and blood was isolated. Blood glucose (Panel B) and plasma cholesterol (Panel C) and insulin (Panel D) levels were determined as described in Materials and Methods. One week later IPGTTs were performed on 6 hr fasted conscious C57BL/6J WT (closed symbols) and Slc30a8 KO (open symbols) male mice as described in Materials and Methods (Panel E). Results represent mean data ± S.E.M. *p<0.05 versus WT.
Figure 5.
Analysis of glucose tolerance in female C57BL/6J Slc30a8 KO mice in vivo.
Intraperitoneal (Panel A) and oral (Panel B) glucose tolerance tests were performed on 6 hr fasted conscious C57BL/6J WT (closed symbols) and Slc30a8 KO (open symbols) female mice as described in Materials and Methods. The IPGTT results show the mean glucose concentrations ± S.E.M. in WT (n = 6; mean age ∼20 weeks) and Slc30a8 KO (n = 8; mean age ∼20 weeks) animals. The OGTT results show the mean glucose concentrations ± S.E.M. in WT (n = 9; mean age ∼22 weeks) and Slc30a8 KO (n = 12; mean age ∼22 weeks) animals.
Figure 6.
Analysis of insulin content and GSIS in female C57BL/6J Slc30a8 KO mouse islets in situ.
Islets were isolated from female WT and Slc30a8 KO mice and then insulin content (Panel A) and GSIS (Panel B) were assayed as described in Materials and Methods. Results show the mean data ± S.E.M. from 6 islet preparations isolated from ∼18 week old female mice. *p<0.05 versus 5 mM glucose.
Figure 7.
Analysis of insulin sensitivity in female C57BL/6J Slc30a8 KO mice in vivo.
Insulin tolerance tests were performed on 5 hr fasted conscious C57BL/6J WT (closed symbols) and Slc30a8 KO (open symbols) female mice as described in Materials and Methods. Results show the mean glucose concentrations ± S.E.M. in WT (n = 8; mean age ∼18 weeks) and Slc30a8 KO (n = 8; mean age ∼18 weeks) animals. In these groups of mice the initial glucose concentration at time zero was higher in KO mice (142.6±6.1 vs 120.8±4.9 mg/dl; p<0.02).
Figure 8.
Normalized expression of selected SLC30 genes by quantitative RT-PCR in 9–23 week old human fetal pancreas and adult human islets.
Data in triplicate (mean ± S.E.M.) is normalized to endogenous GAPDH and quantified and expressed relative to 9 week old fetal samples. SLC30A2 expression was detectable in the fetal pancreas from 19 weeks. *p<0.05 from 9 weeks for SLC30A8 (black bars).