Role of Autophagy in Ovarian Cryopreservation by Vitrification

BACKGROUND

Ovarian cryopreservation by vitrification and transplantation are useful methods to recover female fertility after radiotherapy and chemotherapy. As type II programmed cell death, autophagy plays important roles in ovarian follicle development, ovarian follicle atresia and anti-stress injury.

OBJECTIVE

The potential role of autophagy in ovarian vitrification was investigated.

MATERIALS AND METHODS

Mouse ovaries were cryopreserved by vitrification, and autophagy was treated, after which the ovarian histology was checked, and ovarian follicles were counted. The apoptotic rate was detected by TUNEL, and apoptotic molecular marker cleaved caspase-3 was checked by immunofluorescence and western blot analysis.

RESULTS

Our results suggested that autophagy was increased in the process of vitrification compared with the fresh ovaries (p<0.05). The number of primordial follicles was decreased through inhibiting or over-activating the autophagy by autophagy inhibitor or activator (p<0.05). However, the number of primary follicles, antral follicles and atretic follicles was not significantly different compared with vitrified/warmed groups. The apoptotic rate was significantly increased in the vitrified/warmed, autophagy-inhibiting and over-activating groups compared with the fresh group (p<0.05), and this result was further confirmed by western blot analysis.

CONCLUSIONS

Taken together, autophagy was activated in the ovarian cryopreservation by vitrification and plays a role in a natural adaptive response to cold stress in ovarian cryopreservation by vitrification.

Levothyroxine monotherapy versus levothyroxine and selenium combination therapy in chronic lymphocytic thyroiditis

PURPOSE

New strategies are needed for prevention and treatment of chronic lymphocytic thyroiditis (CLT). This study aimed to assess whether combination of levothyroxine treatment and selenium (Se) supplementation results in improved therapeutic effects in CLT compared with levothyroxine monotherapy.

METHODS

An open-label, randomized controlled study was performed in 60 CLT patients assigned to two groups. Levothyroxine group (LT) patients (n = 24) received levothyroxine alone for 3 months; meanwhile, the combination (LTSS) group (n = 36) was administered levothyroxine with selenium yeast capsule. Blood selenium concentrations, anti-thyroid peroxidase (TPO) and anti-thyroglobulin (Tg) antibody levels, and inflammatory cytokine amounts were compared between both groups before and after treatment.

RESULTS

At baseline, similar values were obtained in both groups for all the parameters assessed (p > 0.05). After treatment, significantly increased blood selenium levels (µg/L) [90.05 (80.69, 107.76) vs. 39.64 (29.42, 51.10), p < 0.001] and decreased anti-TPO antibody (23.63 ± 9.31 vs. 32.00 ± 10.41%, p = 0.002), anti-Tg antibody (35.84 ± 15.21 vs. 45.47 ± 14.24%, p = 0.015) and IL-2 amounts (pg/mL) [159.29 (124.54, 189.70) vs. 226.48 (190.74, 266.56), p < 0.001] were observed in the LTSS group compared with the LT group post-treatment; meanwhile, similar IL-10 concentrations [23.14 (21.65, 28.56) pg/mL vs. 24.68 (21.71, 29.67) pg/mL] were obtained in both groups. Subgroup analysis of patients with hypothyroidism showed the same trend observed in the whole population; in patients with normal thyroid function, only Se and IL-2 amounts differed between the two treatment groups. Correlation analysis of of the indexes: in HT patients, the basal serum selenium concentration was positively correlated with TT₄ (r = 0.294, p < 0.05), significantly negatively correlated with TSH (r = -0.343, p < 0.01), and had no significant correlation with TT3 (p > 0.05).

CONCLUSIONS

These findings indicated that levothyroxine and selenium combination results in improved therapeutic effects than the levothyroxine monotherapy in preventing CLT progression.

Endothelial Progenitor Cells Correlated with Oxidative Stress after Mild Traumatic Brain Injury

PURPOSE

Endothelial progenitor cells (EPCs) play a key role in tissue repair and regeneration. Previous studies have shown that infusion of human umbilical cord blood-derived endothelial colony-forming cells improves outcomes in mice subjected to experimental traumatic brain injury (TBI). However, the efficiency of cell transplantation is not satisfactory. Oxidative stress plays a significant role in the survival of transplanted cells following ischemic reperfusion injury. This observational clinical study investigated the correlation between the number of circulating EPCs and plasma levels of superoxide dismutase (SOD) and malonyldialdehyde (MDA).

MATERIALS AND METHODS

Peripheral blood samples were collected from 20 patients with mild TBI at day-1, day-2, day-3, day-4, and day-7 post TBI. The number of circulating EPCs and the plasma levels of SOD and MDA were measured.

RESULTS

The average of circulating EPCs in TBI patients decreased initially, but increased thereafter, compared with healthy controls. Plasma levels of SOD in TBI patients were significantly lower than those in healthy controls at day-4 post-TBI. MDA levels showed no difference between the two groups. Furthermore, when assessed on day-7 post-TBI, the circulating EPC number were correlated with the plasma levels of SOD and MDA.

CONCLUSION

These results suggest that the number of circulating EPCs is weakly to moderately correlated with plasma levels of SOD and MDA at day-7 post-TBI, which may offer a novel antioxidant strategy for EPCs transplantation after TBI.

Contribution of the PDL to Osteotomy Repair and Implant Osseointegration

Our objective was to clarify the fate of the periodontal ligament (PDL) retained in the socket after tooth extraction, then determine if this tissue contributed to the osseointegration of "immediate" implants placed in these fresh extraction sockets. Mice underwent maxillary first molar extraction, the residual PDL was removed by an osteotomy, and titanium implants were placed. The osteotomy was created in such a way that the palatal surface was devoid of PDL remnants while the buccal, mesial, and distal surfaces retained PDL fibers. At multiple time points after surgery, tissues were analyzed using a battery of molecular, cellular, and histomorphometrical assays. We found that PDL remnants mineralized and directly contributed to new bone formation in the extraction site. Compared with regions of an extraction site where the PDL was removed by osteotomy, regions that retained PDL fibers had produced significantly more new bone. Around immediate implants, the retained PDL remnants directly contributed to new bone formation and osseointegration. Thus, we conclude that PDL remnants are inherently osteogenic, and if the tissue is healthy, it is reasonable to conclude that curetting out an extraction socket prior to immediate implant placement should be avoided. This recommendation aligns with contemporary trends toward minimally invasive surgical manipulations of the extraction socket prior to immediate implant placement.

The revascularization and follicular survival of mouse ovarian grafts treated with FSH during cryopreservation by vitrification

BACKGROUND

Ovarian cryopreservation by vitrification is a very effective pathway for the preservation of female fertility during radiotherapy and chemotherapy. However, damage of follicles was triggered by cryo-injure during the process of ovarian vitrification and ischemia/reperfusion during the process of ovarian transplantation. Appropriate FSH play important roles in anti-apoptosis and neoangiogenesis during ovarian follicle development.

OBJECTIVE

Therefore, the purpose of this study was to investigate the effect of FSH on the revascularization and follicular survival of vitrified-warmed ovarian grafts.

MATERIALS AND TMETHODS

Four-week-old C57BL/6J mice with diestrus were used and the ovaries were randomized into the following three groups: fresh control group (FCG), vitrified/warmed group (VCG) and vitrified/warmed group treated with 0.3 IU/mL FSH (FSH-VG) during ovarian vitrification. After warming, the ovaries of the three groups were allotransplanted into the renal capsule of receptor mice. Assessment of follicular quantity was performed by histological analysis. The angiogenesis factors, CD31 and MMP-2, and cell survival factors, PCNA, EdU and survivin were examined by immunohistochemistry and western blot analysis. Angiogenesis was detected by vascular perfusion with the fluorescent dye 2MD-FITC-Dextran.

RESULTS

The expression of CD31and MMP-2 were not significantly different in either VCG or FSH-VG compared with FCG, but when the ovaries were transplanted 48 hours later, the expression levels of CD31 and MMP-2 were lower for VCG than FCG (P < 0.05) and FSH-VG was not significantly different from FCG. Before transplantation, the expression levels of PCNA and survivin were lower for VCG and FSH-VG than FCG (p < 0.05), but FSH-VG was higher than VCG (p < 0.05). After 48 h of ovarian transplantation, the expression of survivin was lower for VCG than FCG (P < 0.05), but FSH-VG was not significantly different from FCG. In addition, these data were further supported by the results from detecting the 2MD-FITC-Dextran and EdU.

CONCLUSION

Taken together, supplementation with 0.3 IU/mL FSH during ovarian cryopreservation by vitrification increased the revascularization and follicular survival for mouse ovarian grafts through the up-regulated expression of angiogenesis and ovarian survival factors.