Fig 1.
Experimental schedule and indices of non-obesity gestational diabetes mellitus.
(A) Experimental schedule. (B) Body weight. (C) Blood glucose levels. These values were measured at one day before sampling day (virgin) and every other day during gestation (pregnancy). (D) Glucose tolerance test and area under the curve (AUC) for 0 to 120 min. These values were measured on sampling day. Box plot represents the minimum, first quartile, median, third quartile, and maximum (n > 4). Line graph represents the mean ± SE (n > 4). Significant differences: citrate buffer (CB) vs streptozotocin (STZ) in virgin or pregnant status, Mann-Whitney U-test (*: P < 0.05, **: P < 0.01).
Table 1.
IHC protocol used in this study.
Table 2.
List of primers used in this study.
Fig 2.
Indices of reproduction abilities.
(A) Placentas and fetuses in citrate buffer (CB) or streptozotocin (STZ) injected pregnant. (B) Red arrowhead shows absorption scar in STZ-pregnant. Bars = 3 cm. (C) Each number of fetuses and absorption scars. Each weight of the fetus. (D) Histology of corpora lutea in ovary. Squares show the high magnification image of corpora lutea. HE staining. Bars = 400 μm. (E) Each number of corpora lutea. (F) Correlation between blood glucose level (BGL) vs fetus number or absorption scar number at 15.5 gestational days. Resolution of anatomical or histological images: 300 x 300 dpi. Box plot represents the minimum, first quartile, median, third quartile, and maximum (n > 4). Statistical analysis: CB vs STZ in virgin or pregnant status, Mann-Whitney U-test (*: P < 0.05). Significant correlation: Spearman’s correlation coefficient (**: P < 0.01).
Fig 3.
Evaluation of insulin secretion ability.
(A) Plasma C-peptide level. (B) Histological feature of pancreatic islets. HE staining. Bars = 100 μm. Resolution of histological images: 300 x 300 dpi. (C) Pancreatic islet size, area ratio of islets to pancreas, and the number of pancreas islets. Box plot represents the minimum, first quartile, median, third quartile, and maximum (n > 4). Statistical analysis: citrate buffer (CB) vs streptozotocin (STZ) in virgin or pregnant status, and virgin vs pregnant in CB or STZ groups, Mann-Whitney U-test (*: P < 0.05).
Fig 4.
Morphology of pancreatic islets.
(A) Histological features of glucagon+ cells (alpha cells) and insulin/proinsulin+ (beta cells) in the pancreatic islets. Inset magnifies insulin/proinsulin- cells in squared area (arrowhead). Bars = 100 μm. Resolution of histological images: 300 x 300 dpi. (B) Ratio of glucagon+ areas to pancreatic islets. (C) The ratio of glucagon+ areas in the pancreas. (D) Ratio of insulin/proinsulin+ areas to pancreatic islets. (E) The ratio of the insulin/proinsulin+ area to the pancreas. Box plot represents the minimum, first quartile, median, third quartile, and maximum (n > 4). Statistical analysis: citrate buffer (CB) vs streptozotocin (STZ) in virgin or pregnant status, and virgin vs pregnant in CB or STZ groups, Mann-Whitney U-test (*: P < 0.05).
Fig 5.
Genes associated with insulin sensitivity and glucose transportation.
(A) mRNA expression of genes of insulin receptors. (B) mRNA expression of genes of glucose transporters. Representative results are extracted from the S1 Fig. Box plot represents the minimum, first quartile, median, third quartile, and maximum (n > 4). Statistical analysis: citrate buffer (CB) vs streptozotocin (STZ) in virgin (Vir) or pregnant (Pre) status, and Vir vs Pre in CB or STZ groups, Mann-Whitney U-test (*: P < 0.05). CB-Vir: CB-injected virgin. N.D.: not detected.
Fig 6.
Maternal kidney changes due to STZ administration and pregnancy.
(A) The weight of kidney. (B) Appearance score of mice showing urinary glucose. The mice indicating the presence of urinary glucose are scored as 1, while those not indicating are scored as 0. (C) Histology of kidney. Black arrowheads show vacuolar structure in epithelial cells. Red arrowheads show epithelial cell shedding. Bars = 50 μm. Resolution of histological images: 300 x 300 dpi. (D) mRNA expression of genes associated with inflammation and injury. Box plot represents the minimum, first quartile, median, third quartile, and maximum (n > 4). Statistical analysis: citrate buffer (CB) vs streptozotocin (STZ) in virgin (Vir) or pregnant (Pre) status, and Vir vs Pre in CB or STZ groups, Mann-Whitney U-test (*: P < 0.05). CB-Vir: CB-injected virgin. A chi-square test are performed to analyze whether there was a significant difference in the urinary glucose between the two groups (P < 0.05).
Fig 7.
Maternal liver changes due to STZ administration and pregnancy.
(A) Histology of liver. Black arrowheads show PAS+ cells. Red arrowheads show ADRP/ Perilipin2+ cells. (B) Number of large lipid droplets. (C) Liver weight. Each bar represents the mean ± SE (n > 4). Bars = 100 μm. Resolution of histological images: 300 x 300 dpi. Box plot represents the minimum, first quartile, median, third quartile, and maximum (n > 4). Statistical analysis: citrate buffer (CB) vs streptozotocin (STZ) in virgin or pregnant status, and virgin vs pregnant in CB or STZ groups, Mann-Whitney U-test (*: P < 0.05).