Effect of Silibinin on Dyslipidemia and Glycemic Alteration Associated with Polycystic Ovarian Syndrome: An Experimental Study on Rats

Figures & data

Figure 1 Flowchart of the study design.

Abbreviations: PCOS, polycystic ovary syndrome-induced group; MET, metformin; LD-100, low-dose silibinin; HD-200, high-dose silibinin.

Figure 2 Vaginal cytology of rats showing phases of the estrus cycle with the cell type characterized as: (A) proestrus: consists of a predominance of nucleated epithelial cells; (B) estrus: cornified squamous epithelial cells; (C) metestrus: consists of mixed cells of leukocytes, nucleated cells (few), and cornified squamous epithelial cells; (D) diestrus: leukocytes are predominant.

Note: Magnification: ×10.

Table 1 Body Weight Changes of the Rats Throughout the Treatment Period

Groups	Day 1: Before LZ Administration (g) (n=6)	Day 21: After a 21-Day Administration of LZ (g) (n=6)	Day 40: After a 19-Day Administration of the Treatments (g) (n=6)
Control	154±4.85	188±9.03	191±7.31
PCOS	151±7.81	220±11.73*	221±11.45
MET	159±4.00	236±2.92***	235±2.74*
LD-100	148.6±5.56	231.6±5.88**	222.6±6.02^#
HD-200	148±3.39	229±5.10**	227.6±6.76

Notes: Values are presented as mean±SEM, n=6 rats per each group. Two-way repeated measure ANOVA was used. *p<0.05, **p<0.01, ***p<0.001: significantly different versus control. ^#Significantly different between different time-points (days 21 and 40).

Abbreviations: PCOS, polycystic ovary syndrome-induced group; MET, metformin; LD-100, low-dose silibinin; HD-200, high-dose silibinin; LZ, letrozole.

Table 2 Relative Ovarian and Uterine Weights, and Abdominal Fat Weight, on Day 40

Groups	Relative Weight of Ovary at the End of the Experiment (g)	Relative Weight of Uterus at the End of the Experiment (g)	Abdominal Fat at the End of the Experiment (g)
Control	0.038±0.002	0.212±0.021	3.478±0.322
PCOS	0.044±0.002	0.170±0.024	3.782±0.270
MET	0.042±0.004	0.182±0.018	3.528±0.526
LD-100	0.048±0.002	0.222±0.030	2.354±0.366
HD-200	0.042±0.004	0.144±0.017	1.750±0.138*^a

Notes: Values are presented as mean±SEM, n=6 rats per each group. One-way ANOVA was used. *p<0.05: significantly different versus control. Superscript letter (a) indicates significant difference from the PCOS group.

Abbreviations: PCOS, polycystic ovary syndrome-induced group; MET, metformin; LD-100, low-dose silibinin; HD-200, high-dose silibinin.

Figure 3 Effect of silibinin on oral glucose tolerance test on (A) day 21 and (B) day 40.

Notes: Values are expressed as mean±SEM, n=6 rats per each group. Two-way repeated measure ANOVA was used, followed by Tukey’s multiple comparison test. Non-identical letters (a,b,c,d) indicate significant differences between different time-points and different groups.

Abbreviations: PCOS, polycystic ovary syndrome-induced group; MET, metformin; LD-100, low-dose silibinin; HD-200, high-dose silibinin.

Table 3 Area Under the Curve for Oral Glucose Tolerance Test on Days 21 and 40

Groups	AUC (mg.min/dL) – Day 21	AUC (mg.min/dL) – Day 40
Control	13,116±371	13,047±422.2
PCOS	15,813±883.3	14,583±441.1
MET	17,151±633.5	14,274±516.8
LD-100	16,167±292.1	14,607±383.5
HD-200	15,360±489.3	14,499±477.6

Notes: Values expressed as mean±SEM. One-way ANOVA followed by Tukey’s multiple comparison test was used.

Abbreviations: AUC, area under the curve of blood glucose; PCOS, polycystic ovary syndrome-induced group; MET, metformin; LD-100, low-dose silibinin; HD-200, high-dose silibinin.

Figure 4 Effects of silibinin on serum insulin level on day 40.

Notes: Values are presented as mean±SEM, n=6 rats per each group. One-way ANOVA was used, followed by Tukey’s test.

Abbreviations: PCOS, polycystic ovary syndrome-induced group; MET, metformin; LD-100, low-dose silibinin; HD-200, high-dose silibinin.

Figure 5 Effect of silibinin on lipid profile on day 40, including serum (A) cholesterol, (B) triglyceride, (C) low-density lipoprotein, (D) high-density lipoprotein.

Notes: Values are expressed as mean±SEM, n=6 rats per each group. Ordinary one-way ANOVA was used, followed by Tukey’s multiple comparison test.

Abbreviations: PCOS, polycystic ovary syndrome-induced group; MET, metformin; LD-100, low-dose silibinin; HD-200, high-dose silibinin.