Background: Age-related diminished ovarian reserve (AR-DOR) reduced the quality of oocytes, resulting in decreased female fertility. Aging is tightly related to abnormal distribution and function of mitochondria, while mitophagy is a major process to maintain normal quality and quantity of mitochondria in cells, especially in oocytes which containing a large number of mitochondria to meet the demand of energy production during oocyte maturation and subsequent embryonic development. Ampk/FoxO3a signaling is crucial in the regulation of mitophagy. It is reported mesenchymal stem cells (MSCs) can improve ovarian function. Here we aim to explore if human amnion-derived mesenchymal stem cells (hAMSCs) are effective in improving ovarian function in AR-DOR mice and whether Ampk/FoxO3a signaling is involved. Methods: The AR-DOR model mice were established by 32-week-old mice with 3–8 litters, significantly low serum sex hormone levels and follicle counts. The old mice were divided into 5 treatment groups: normal saline (NS, control), 1% human serum albumin (HSA, resolver), low dose (LD, 5.0 × 10⁶cells/kg), middle dose (MD, 7.5 × 10⁶cells/kg), and high dose (HD, 10.0 × 10⁶cells/kg). The prepared hAMSCs were injected through tail vein. Serum sex hormone level, follicle counts, fertilization rate, gestation rate, little size, apoptosis of granulosa and stromal cells, expression level of Sod2, Ampk, and ratio of phosphorylated FoxO3a to total FoxO3a in ovaries were examined. Results: Our results show that after hAMSC transplantation, the ovarian function in AR-DOR mice was significantly improved, meanwhile the apoptosis of granulosa and stromal cells in the ovaries was significantly repressed, the expression level of Ampk and the ratio of phosphorylated FoxO3a to total FoxO3a both were significantly increased, meanwhile increased Sod2 expression was also observed. Conclusion: Our results demonstrate hAMSC transplantation via tail-injection can improve ovarian function of AR-DOR mice through Ampk/FoxO3a signaling pathway.

Background: Studies have shown that chemotherapy and radiotherapy can cause premature ovarian failure and loss of fertility in female cancer patients. Ovarian cortex cryopreservation is a good choice to preserve female fertility before cancer treatment. Following the remission of the disease, the thawed ovarian tissue can be transplanted back and restore fertility of the patient. However, there is a risk to reintroduce cancer cells in the body and leads to the recurrence of cancer. Given the low success rate of current in vitro culture techniques for obtaining mature oocytes from primordial follicles, an artificial ovary with primordial follicles may be a good way to solve this problem. Methods: In the study, we established an artificial ovary model based on the participation of mesenchymal stem cells (MSCs) to evaluate the effect of MSCs on follicular development and oocyte maturation. P2.5 mouse ovaries were digested into single cell suspensions and mixed with bone marrow derived mesenchymal stem cells (BM-MSCs) at a 1:1 ratio. The reconstituted ovarian model was then generated by using phytohemagglutinin. The phenotype and mechanism studies were explored by follicle counting, immunohistochemistry, immunofluorescence, in vitro maturation (IVM), in vitro fertilization (IVF), real-time quantitative polymerase chain reaction (RT-PCR), and Terminal-deoxynucleotidyl transferase mediated nick end labeling(TUNEL) assay. Results: Our study found that the addition of BM-MSCs to the reconstituted ovary can enhance the survival of oocytes and promote the growth and development of follicles. After transplanting the reconstituted ovaries under kidney capsules of the recipient mice, we observed normal folliculogenesis and oocyte maturation. Interestingly, we found that BM-MSCs did not contribute to the formation of follicles in ovarian aggregation, nor did they undergo proliferation during follicle growth. Instead, the cells were found to be located around growing follicles in the reconstituted ovary. When theca cells were labeled with CYP17a1, we found some overlapped staining with green fluorescent protein(GFP)-labeled BM-MSCs. The results suggest that BM-MSCs may participate in directing the differentiation of theca layer in the reconstituted ovary. Conclusions: The presence of BM-MSCs in the artificial ovary was found to promote the survival of ovarian cells, as well as facilitate follicle formation and development. Since the cells didn’t proliferate in the reconstituted ovary, this discovery suggests a potential new and safe method for the application of MSCs in clinical fertility preservation by enhancing the success rate of cryo-thawed ovarian tissues after transplantation.

Calciphylaxis is a rare disease characterized histologically by microvessel calcification and microthrombosis, with high mortality and no proven therapy. Here, we reported a severe uremic calciphylaxis patient with progressive skin ischemia, large areas of painful malodorous ulcers, and mummified legs. Because of the worsening symptoms and signs refractory to conventional therapies, treatment with human amnion-derived mesenchymal stem cells (hAMSCs) was approved. Preclinical release inspections of hAMSCs, efficacy, and safety assessment, including cytokine secretory ability, immunocompetence, tumorigenicity, and genetics analysis in vitro, were introduced. We further performed acute and long-term hAMSC toxicity evaluations in C57BL/6 mice and rats, abnormal immune response tests in C57BL/6 mice, and tumorigenicity tests in neonatal Balbc-nu nude mice. After the preclinical research, the patient was treated with hAMSCs by intravenous and local intramuscular injection and external supernatant application to the ulcers. When followed up to 15 months, the blood-based markers of bone and mineral metabolism improved, with skin soft tissue regeneration and a more favorable profile of peripheral blood mononuclear cells. Skin biopsy after 1-month treatment showed vascular regeneration with mature noncalcified vessels within the dermis, and 20 months later, the re-epithelialization restored the integrity of the damaged site. No infusion or local treatment-related adverse events occurred. Thus, this novel long-term intravenous combined with local treatment with hAMSCs warrants further investigation as a potential regenerative treatment for uremic calciphylaxis due to effects of inhibiting vascular calcification, stimulating angiogenesis and myogenesis, anti-inflammatory and immune modulation, multidifferentiation, re-epithelialization, and restoration of integrity.

Calciphylaxis is a rare cutaneous vascular disease that manifests with intolerable pains, non-healing skin wounds, histologically characterized by calcification, fibrointimal hyperplasia, and microvessel thrombosis. Currently, there are no standardized guidelines for this disease. Recent studies have recognized a high prevalence of thrombophilias and hypercoagulable conditions in calciphylaxis patients. Here, we report a case of uremic calciphylaxis patient whom was refractory to conventional treatments and then received a salvage strategy with intravenous and local hAMSC application. In order to investigate the therapeutic mechanism of hAMSCs from the novel perspective of hypercoagulability, coagulation-related indicators, wound status, quality of life and skin biopsy were followed up. Polymerase chain reaction (PCR) was performed to determine the distribution of hAMSCs in multiple tissues including lung, kidney and muscle after infusion of hAMSCs for 24 h, 1 week and 1 month in mice aiming to investigate whether hAMSCs retain locally active roles after intravenous administration. Improvement of hypercoagulable condition involving correction of platelet, D-dimer and plasminogen levels, skin regeneration and pain alleviation were revealed after hAMSC administration over one-year period. Skin biopsy pathology suggested regenerative tissues after 1 month hAMSC application and full epidermal regeneration after 20 months hAMSC treatment. PCR analysis indicated that hAMSCs were homing in lung, kidney and muscle tissues of mice even until tail vein injection of hAMSCs for 1 month. We propose that hypercoagulability is a promising therapeutic target of calciphylaxis patients, which can be effectively improved by hAMSC treatment.

Targeting senescent pancreatic β‐cells represents a promising therapeutic avenue for age‐related diabetes; however, current anti‐senescence strategies often compromise β‐cell mass. In this study, human amniotic mesenchymal stem cell‐derived small extracellular vesicles (hAMSC‐sEVs) were identified as a novel intervention that can be used to effectively counteract cellular senescence and preserve β‐cell integrity. We aimed to systemically delineate the molecular mechanisms underlying hAMSC‐sEV‐mediated reversal of β‐cell senescence in age‐related diabetes. In oxidative stress‐induced and naturally aged β‐cell models, hAMSC‐sEVs mitigated senescence‐associated phenotypes, restored mitochondrial homeostasis, and enhanced insulin secretion capacity. In aged diabetic mice, administering these vesicles significantly ameliorated hyperglycemia, improved glucose tolerance, and reversed β‐cell functional decline by reducing senescent β‐cell populations, reinstating β‐cell identity markers, and suppressing senescence‐associated secretory phenotype (SASP) component production. Mechanistic investigations revealed that the miR‐21‐5p‐enriched hAMSC‐sEVs directly target the interleukin (IL)‐6 receptor α subunit (IL‐6RA), thereby inhibiting signal transducer and activator of transcription 3 (STAT3) phosphorylation at tyrosine 705 and its subsequent nuclear translocation. This epigenetic modulation alleviated STAT3‐mediated transcriptional repression of the mitochondrial calcium uniporter (MCU), rectifying age‐related mitochondrial calcium mishandling and insulin secretion defects. Genetic ablation of MCU clearly established the central role of the miR‐21‐5p/IL‐6RA/STAT3/MCU axis in this regulatory cascade. Our findings reveal hAMSC‐sEVs as a novel senotherapeutic strategy for age‐related diabetes, elucidating the pivotal role of miR‐21‐5p‐driven epigenetic–mitochondrial calcium homeostasis in reversing β‐cell dysfunction, establishing a framework for targeting cellular senescence in metabolic disorders.