BMI (g/cm²) and fasting blood glucose level (mmol/L) of zebrafish following over-feeding with HFD and standard diet for 4 weeks. Values are means (± SD), (*P) indicates a significant difference (P < 0.05) among the values, with n = 8. NS no significant difference, SD standard diet, HFD high-fat diet. Exemplary images of zebrafish (C: female; D: male) were included in each of the analyzed dietary groups at week 4 of feeding. Red arrows point to the abdominal region. Overfeeding with the high-fat diet of zebrafish showed a significant increase in weight and length.

Glucose tolerance test (GTT) and area under the curve (AUC) of male and female zebrafish fed an HFD versus SD. Blood glucose levels were measured after fasting for 0, 30, and 120 min, and following an oral dose of 1.25 mg glucose/g body weight; Values are means (± SD), (*P) indicates significant difference (P < 0.05) among the values, n = 8 in each time point. SD: standard diet. HFD: high-fat diet.

BMI (A) (g/cm²) and fasting blood glucose level (B) (mmol/L) of non-treated and treated male and female zebrafish with different concentrations of DL-limonene following HFD and SD. Values are means (± SD), (*P) indicates a significant difference (P < 0.05) among the values, n = 6. SD: standard diet. HFD High-fat diet.

The PCA score (A and C) and loading (B and D) plots (PC1 vs. PC2) compare the HFD with the SD male zebrafish of aqueous and lipophilic metabolites after 4 weeks of treatment. HFD high fat diet, SD stander diet.

The OPLS-DA score plot (A and C) and S-plot (C and D) of aqueous (A and B) and lipophilic (C and D) metabolites of HFD and SD male zebrafish after 4 weeks of treatment. HFD high fat diet, SD stander diet.

The PCA score (A and C) and loading (B and D) plots (PC1 vs. PC2) compare the HFD with the SD female zebrafish of aqueous and lipophilic metabolites after 4 weeks of treatment. HFD high fat diet, SD stander diet.

The OPLS-DA score plot (A and C) and S-plot (C and D) of aqueous (A and B) and lipophilic (C and D) metabolites of HFD and SD female zebrafish after 4 weeks. HFD high fat diet, SD stander diet.

The PLS-DA score (A and C) and loading column (B and D) plots of the aqueous metabolites (A and B) and lipophilic metabolites (C and D) show the effects of low and high doses (5 and 20 mg/L) of DL-limonene on male diabesity zebrafish after 4 weeks of treatment.

The heatmap of aqueous (A) and lipophilic (B) metabolites showing the effects of low and high doses of DL-limonene on the treated obese diabesity male zebrafish after 4 weeks of treatment. HFD high fat diet, SD stander diet, 20 20 mg/L, 5 5 mg/L, HFDm high fat diet methanol, SDm stander diet methanol.

The VIP values were derived from PLS-DA of aqueous (A) and lipophilic (B) metabolites of diabesity male zebrafish. HFD high fat diet, SD stander diet, 20 20 mg/L, 5 5 mg/L, HFDm high fat diet methanol, SDm stander diet methanol.

The PLS-DA score (A and C) and loading column (B and D) plots of the aqueous metabolites (A and B) and lipophilic metabolites (C and D) show the effects of low and high doses (5 and 20 mg/L) of DL-limonene on female diabesity zebrafish after 4 weeks of treatment.

The heatmap of aqueous (A) and lipophilic (B) metabolites showing the effects of low and high doses of DL-limonene on the treated diabesity female zebrafish after 4 weeks of treatment. HFD high fat diet, SD standard diet, 20 20 mg/L, 5 5 mg/L, HFDm high fat diet methanol, SDm standard diet methanol.

The VIP values were derived from PLS-DA of aqueous (A) and lipophilic (B) metabolites of diabesity female zebrafish. HFD high fat diet, SD standard diet, 20 20 mg/L, 5 5 mg/L, HFDm high fat diet methanol, SDm standard diet methanol.

Metabolic pathways and metabolite changes observed in diabetic (A) male and (B) female (B) zebrafish.

The foldchange of the tested liver (A: Female; B: Male) and brain (C: Female; D: Male) genes.