5.1 Mechanism of Shawkea DE-T1 on reproduction health
From years of clinical observation we discerned that Shawkea DE-T1 administration improved the success rate of IVF-ET. The follicle-stimulating hormone (FSH) receptor is the only gonadotropin receptor present on the ovarian granulosa cell surface during early folliculogenesis, and previous studies have confirmed that Shawkea DE-T1 increased the activities of FSH, luteinizing hormone, and other related reproductive hormones and their receptors on the surfaces of ovarian granulosa cells[5, 9]. A previous group showed that growth hormone (GH) was also involved in many processes underlying human reproduction. During Oocyte development process, GH could promote cell maturation and increase receptor activity in granulosa cells [10], and additional research indicates that the effect of GH on reproduction is principally its promotion of insulin-like growth factor (IGF) secretion [11]. IGF is a molecule that effectively promotes granulosa cell activities, and extant studies show that dandelion polysaccharides increase the activity of the IGF-related receptor and also exert blood-glucose lowering, hepatoprotective, and antioxidative effects [1–4]. Our previous investigation revealed that the embryonic implantation rate and live-birth rate after IVF treatment significantly declined with age, and that the decline was more obvious after the age of 40 [8]. Diminished oocyte quality due to aging in women is usually due to meiotic nondisjunction of oocyte chromosomes, resulting in an elevation in the rate of aneuploidy in early embryos and an increase in the rate of spontaneous abortion. The most common autosomal trisomies, for example, are caused by abnormal chromosomal spindle arrangement and filament-matrix composition during meiosis of oocytes in women of advanced reproductive age [11, 12].
The patients who experienced embryo transfer in previous study[7] were 30–46 years old, with a mean age of 36.10 ± 3.97 years. We noted no significant difference in the age of the two groups of patients, and all patients were at a relatively advanced reproductive age. In our previous study [7] we compared the live-birth rate for women with and without Shawkea DE-T1 administration, and our results revealed that the rate for treated women was 57.53%; this was significantly higher than that of the control group at 40.00% (x2 = 4.48, P = 0.045), and suggested that Shawkea DE-T1 significantly improved the live-birth rate of women treated with IVF. Mechanistically, Shawkea DE-T1 may significantly improve blastocyst obtained rate in patients received IVF treatment, so they have more blastocysts available for embryo transfer. In addition, a study showed that multiple receptor types exist in the ovaries and uterus, and Shawkea DE-T1 can up-regulate the activity of these receptors and thereby balance the secretion of female reproductive hormones [6]. Dandelion polysaccharide also promotes the secretion of GH and affects related receptors [1–4], and play roles in oocyte growth, embryonic implantation, and fetal development. Thus, Shawkea DE-T1 may improve the quality of oocytes during IVF and promote the production of high-quality, fertilized oocytes. Combining the above functions with the results of our previous and current findings, we hypothesize that Shawkea DE-T1 significantly increases blastocyst obtained rate in women undergoing IVF treatment, and its underlying mechanism may be related to promoting the secretion of GH, thereby increasing the numbers of granulosa cells, inhibiting the decline in granulosa cells, and promoting ovulation. GH actions may involve multiple organs, pathways, and targets—including hypoglycemia, antioxidation, and hepatoprotection. Therefore, the improvement in live-birth rate with Shawkea DE-T1 administration observed in our previous trail may be achieved via its two major effects: increasing the overall number of blastocysts and improving blastocyst quality. Given the complex physiologic processes involved in reproduction, further research is necessary to delineate the multi-target synergistic mechanisms of Shawkea DE-T1 on different organs of the hypothalamic-pituitary-ovarian-uterine axis.
5.2 Effects of different Shawkea DE-T1 administration durations on the blastocyst obtained rate in women
With the continuous development of ART, blastocyst culture has become more widely employed. Compared with primary embryos, the transfer of embryos grown to the blastocyst stage improves the synchronization of embryos with endometrial receptivity, increases in vitro screening of embryos, and achieves favorable pregnancy and implantation rates [13, 14]. Blastocyst culture effectively eliminates embryos with poor potential or that show chromosomal abnormalities during their development from cleavage to blastocyst stage, thereby improving the pregnancy outcome with blastocyst transfer [15–17]. Blastocyst transfers have increased globally over recent years and currently account for over 50% of all embryo transfers [18, 19]. Hence, in this study we focused on the effect of different administration durations of Shawkea DE-T1 on in vitro blastocyst obtained rate in women undergoing IVF treatment. The blastocyst obtained rate reflected the percentage of patients who ultimately obtained at least one blastocyst after treatment relative to the total number of patients in the same group, suggesting that these patients achieved the opportunity to transfer blastocysts and that they exhibited a higher pregnancy rate than patients undergoing transfer of early embryos. Blastocyst obtained rate was thus an important predictor of the treatment outcomes with IVF.
Due to the ethics involved and a respect for honoring patient wishes, we did not artificially create an observation period but only conducted dosage guidance and follow-ups on the Shawkea DE-T1 administration conditions. A majority of the patients in the administration group started Shawkea DE-T1 administration 1–3 months before oocyte retrieval, and the administration duration of Shawkea DE-T1 was determined by the patients according to the results of oocyte retrieval and embryo culture. Under normal circumstances, patients with difficulties in oocyte retrieval and blastocyst culture underwent multiple oocyte retrievals and experienced a relatively long treatment duration. Thus, we compared the blastocyst rates of two groups of patients undergoing different treatment durations (1–3 months, 4–6 months, and > 6 months), and our results showed that the rates of the patients undergoing 1–3 months and 4–6 months of treatment durations in the administration group were significantly higher than those in the control group (P < 0.05), suggesting that patients administered Shawkea DE-T1 achieved a higher blastocyst rate during the same treatment duration.
In another perspective, the blastocyst rate of the patients who underwent a 1–3-month Shawkea DE-T1 administration was 83.27% higher than that for patients who received 4–6 months of treatment (69.44%). The blastocyst rates declined with the extension of Shawkea DE-T1 administration durations, and we speculate that this result may be determined by the basic physiologic conditions of the patients in the corresponding treatment durations. The patients showing healthy basic conditions achieved blastocyst formation after 1–3 months of Shawkea DE-T1 administration, while the patients who did not generate a blastocyst required a longer Shawkea DE-T1 administration period (4–6 months). Given the differences in the basic physiologic conditions of the patients undergoing 1–3 months and 4–6 months of Shawkea DE-T1 administrations, the blastocyst rates between the two groups could not be compared directly.
We posit that the analysis of blastocyst rate should be performed taking three months as a treatment duration, however the patients in the administration group of this study experienced various treatment durations (varying from 1–40 months). With the extension in treatment duration the number of patients in each treatment-duration group was relatively small. In addition, the overall data distribution was quite different, and the heterogeneity of the corresponding data was high. For the reasons above, the data over six months was not suitable for statistical analysis. Therefore, the comparison of the blastocyst rates between the two groups of patients undergoing more than six months of treatment showed no significant differences between groups (P > 0.05). A study of larger sample size is warranted in the future to provide additional observations.
5.3 Optimization of Shawkea DE-T1 administration duration for women at different ages in order to acquire satisfactory therapeutic efficacy
The results of this study revealed that for women who successfully produced a blastocyst, there were differences in Shawkea DE-T1 administration durations for the different age groups. For women ≥ 30 and < 35 years of age, 65.25% patients successfully achieved blastocyst within one to three months of Shawkea DE-T1 administration, and only 9.93% underwent treatment > 6 months to produce a blastocyst. For women ≥ 43 years of age, only 19.75% successfully achieved blastocyst within one to three months of Shawkea DE-T1 administration, while 53.09% required > 6 months. We therefore recommend that Shawkea DE-T1 administration duration be adjusted according to the baseline conditions of the women (including age), and not be generalized. For women who attempt to conceive at an advanced reproductive age, a sufficient Shawkea DE-T1 administration duration may be more conducive to producing a high quality blastocyst upon embryo culture after IVF.
In conclusion, in this study we analyzed the influences of different Shawkea DE-T1 administration durations on blastocyst obtained rate, and further assessed the rates with actual Shawkea DE-T1 administration durations in women in different age levels who obtained blastocyst successfully in IVF treatment. Our result indicated that Shawkea DE-T1 administration increased the blastocyst obtained rate for 1–3-months and 4–6-months of treatment (P < 0.05). Due to insufficient sampling of the patients who underwent > 6 months of treatment, we did not note any significant differences in blastocyst obtained rate compared with the patients in the control group (P > 0.05). Analysis of the treatment durations with Shawkea DE-T1 in women who achieved blastocyst also suggested that women of advanced reproductive age should extend Shawkea DE-T1 administration duration to achieve better therapeutic efficacy.