Photobiomodulation can improve ovarian folliculogenesis and steroidogenesis in polycystic ovary syndrome‐induced rats

Abstract

Photobiomodulation (PBM) has been investigated and used in clinical practice, related to biomodulatory influences on cellular functions in animals and humans. The absorption of photons by the photoreceptors causes changes in the molecular configuration of these receptors and activate molecular signals in the cells. Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorder in women of reproductive age, and it has a prevalence of 2% to 27%. Diagnosis of PCOS requires two of the following: polycystic ovaries, hyperandrogenism, and oligomenorrhea or amenorrhea. The cause of PCOS is still unknown and animal models PCOS‐induced are important tools for understanding the pathophysiology of the syndrome. We aimed to analyze the PBM effects on follicle and cyst numbers, and ovarian testosterone (T) synthesis in a rat PCOS model induced by estradiol valerate (EV). Twenty adult Wistar rats (n = 5 per group) were divided into control (C), PCOS, PBM, PCOS/PBM groups. PCOS was induced by single injection of EV (2 mg/kg/bw/i.m.). The animals were irradiated with a laser (wavelength 808 nm, power 60 mW), using a dose of 1 Joules(J)/point on each ovary, 3 times weekly, totaling 2 J of energy for each irradiated animal per day of application. The animals were evaluated 30, 45, and 60 days after treatments. After sacrifice, plasma T was determined, and the ovaries were collected and prepared for histological analysis. Statistical analysis: ANOVA and Fisher's test. The results were reported as means ± SD. This study was approved by the local Animal Care and Use Committee (protocol n° 030/2016). T: PCOS group: The 60‐day (1.075 ± 0.612 pg/mL) and 45‐day (0.049 ± 0.0465 pg/mL) groups showed increased T, compared to the 30‐day (0.01568 ± 0.00869 pg/mL). PCOS/PBM group: The 60‐day (0.2653 ± 0.1706 pg/mL) and 45‐day (0.04136 ± 0.01667 pg/mL) groups showed increased T, compared to the 30‐day (0.04172 ± 0,01875 pg/mL). After 60 days of treatments, the C (0.1062 ± 0.0988 pg/mL) and PBM (0.0836 ± 0.1706 pg/mL) groups presented lower T, compared to PCOS (1.075 ± 0.612 pg/mL) and PCOS/PBM (0.2653 ± 0.1706 pg/mL) groups. Ovaries: the highest number of follicular cysts (6.33 ± 1.52) occurred in the PCOS group 60 days after EV injection, while the lowest number of follicular cysts was observed in the C group (0.33 ± 0.57). The 60‐day PCOS/PBM group presented fewer (3 ± 1) follicular cysts than the PCOS group, but more follicular cysts than the C group. The highest number of follicles was observed in 30‐day C (8 ± 1) group, while the lowest number was observed in the 60‐day PCOS (1.66 ± 0.57) group. The number of follicles found for the 60‐days PCOS/PBM (6.66 ± 0.57) group was higher than for the PCOS group and equal to the C group. It could be concluded that the PBM reduced plasma T of the PCOS group, decreased the number of follicular cysts and increased the number of ovarian follicles in the PCOS/PBM group, compared to the PCOS group, apparently restoring the ovarian folliculegenesis and steroidogenesis activities. Support or...

Therapeutic effects of aqueous extract of bioactive active component of Ageratum conyzoides on the ovarian-uterine and hypophysis-gonadal axis in rat with polycystic ovary syndrome: Histomorphometric evaluation and biochemical assessment

“…The influence of hormonal changes on reproductive tissues revealed that leukocyte entry into uterine tissues is mostly controlled by hormones [ 96 ]. PCOS has been shown to cause histo-architectural abnormalities in the ovary [ 97 ] and uterine of rats [ 98 ].This study found that PCOS rats have the leastcorpus luteum and numerous follicular ovarian cysts, which is consistent with animal models of PCOS [ 99 , 100 ]. Reduced levels of testosterone, FSH, LH, and antioxidant activity might be linked to decreased ovarian weight, uterine length and weight, endometrium thickness, and endometrial gland numbers.…”

Normotensive rats with PCOS exhibit the hypertensive pattern: focus on oxidative stress

“…The PCOS induction lowered significantly all investigated parameters except D2, while the strain differences between WK and SHR were observed only regarding OV/ BW index. Besides the well-known parameter termed 'gonadosomatic index' (Alves et al 2019), we tried to estimate a new parameter -OV/BW index, which gave a better insight into group differences. Therefore, we assumed that OV/BW index might be a useful tool for estimating OV alterations in PCOS rat studies.…”