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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...

Polycystic ovary syndrome (PCOS) is one of the most widely recognized endocrine disorders affecting reproductive-age women. The etiopathogenesis and mechanisms of this syndrome remain unclear. Diagnosis requires two of the following: polycystic ovaries, oligo- or anovulation, and hyperandrogenism. Most women with PCOS display conditions such as metabolic abnormalities, diabetes, obesity, cardiovascular disease, and/or bone dysfunction. Considering the ethical limitations of human studies, animal and cell culture models that reflect some features of PCOS are important for investigation of this syndrome. The aim of the present work was to study some of the endocrine relationships between ovaries and bone tissue in a polycystic ovary syndrome animal model. The study was performed using an estradiol valerate PCOS-induced rat model (n = 30) and bone mesenchymal stem cell cultured from bone marrow of those animals. It was hypothesized that changes of the endocrine relationship between ovaries and bones could be observed in from in vivo animal model and in vitro cell culture assays. The ovarian morphological and endocrine changes seem to be correlated with endocrine, biophysical, and biomechanical changes in bone properties. Mesenchymal stem cells obtained from PCOS-induced rats, cultured for up to 21 days and differentiated into osteoblasts, presented lower viability and reduced mineralization of the extracellular matrix. Taken together, these results indicate important endocrine and structural effects of PCOS in ovaries and bones, contributing to part of the understanding of the pathophysiological mechanisms of PCOS.

Female rats induced to polycystic ovary (PCO) present ovarian alterations in both folliculogenesis and steroidogenesis. There are a reductions in the numbers of follicles and corpora lutea, in addition to the appearance of follicular cysts. Hyperandrogenemia is a consequence of steroidogenic alterations that induce irregular estral cycles and folliculogenesis. Low‐level laser therapy (LLLT) and light‐emitting diode (LEDs) therapy have been investigated and used in clinical practice concernig the biomodulation of cellular functions both in vivo and in vitro. The objective of this study was to analyze the effects of LLLT on the number of ovarian follicular cysts in PCO rats. Forty‐five female adult Wistar rats weighing 250–300 g were divided into control (n = 15), PCO (n = 15) and PCO/laser (n = 15) groups. PCO in the rats was induced by single injection of estradiol valerate (EV) (2 mg/kg/bw, i.m.). After PCO induction, the rats were divided into groups evaluated 30, 45, and 60 days after the injections. The animals were manually contained and irradiated with a laser (wavelength 808 nm, power 60 mW) using a dose of 3 Joules(J)/point for 18 seconds on the dorsal region, performing a transillumination on each ovary 3 times a week, totaling 6 J of energy per irradiated animal/per day of application. After sacrifice, the ovaries were collected for preparation and subsequent analysis of histological slides. The results were reported as means ± SEM. Statistically significant differences among the means for the treatment groups were identified using p<0.05. This study was approved by the local Animal Care and Use Committee (CEUA–UNIARA, protocol n° 019/16). The findings showed that the highest number of follicular cysts (6.33 ± 1.52) occurred in the PCO group 60 days after EV injection, while the lowest number of follicular cysts was observed in the control group (0.33 ± 0.57). The PCO animals submitted to LLLT for 60 days presented fewer (3 ± 1) follicular cysts than the PCO animals, but more follicular cysts than the control animals. The highest number of follicles was observed in the control group after 30 days (8 ± 1), while the lowest number was observed in the PCO group after 60 days (1.66 ± 0.57). The number of follicles found for the 60‐days PCO/laser group (6.66 ± 0.57) was higher than for the PCO group and equal to the control group. It could be concluded that the use of LLLT decreased the number of follicular cysts and increased the number of ovarian follicles in the PCO/laser group, compared to the PCO group, apparently restoring the ovarian folliculogenesis activity.Support or Funding InformationGrant #2016/02811‐4. São Paulo Research Foundation (FAPESP).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

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