[Advances in the study of ovarian dysfunction with aging].

Societal changes regarding the role of women have significant impacts on women's willingness and the timing of childbearing. Ovarian reserve in woman typically begins to decline at the age of 35, and it is primarily characterized by a reduction in the number of ovarian follicles and a decline in oocyte quality. The clinical diagnosis of ovarian insufficiency relies on multiple variables including changes of follicle stimulating hormone (FSH), serum anti-Müllerian hormone (AMH), inhibin B, antral follicle count, menstruation and age. It is proven that ovarian cells demonstrate dysfunction associated with aging including mitochondrial dysfunction, telomere shortening, impaired DNA repair, epigenetic changes and metabolic/energetic disorders. In this review, we introduce the clinical diagnosis and management of ovarian insufficiency. We mainly discuss the molecular mechanism and potential interventions. We are optimistic that this information and knowledge will inform the important decisions for women and society regarding childbearing.

Evolution and modeling of texture changes and drying kinetics of bamboo shoots under high-humidity air-impingement blanching.

This study investigated the effect of hot water blanching (HWB), high-humidity air-impingement blanching (HHAIB), different HHAIB blanching times (2, 4, 6, 8, and 10 min), and different HHAIB blanching temperatures (80, 85, 90, and 95°C) on texture quality, lignin content, weight loss, color, microstructure, and drying kinetics of bamboo shoots. After HWB treatment, the lignin content of bamboo shoots was apparently lower than that of HHAIB and the samples obtained the highest weight loss value of 6.13%. Both the texture values (brittleness and chewiness) and lignin content of bamboo shoots exhibited an overall downward trend as the HHAIB blanching time and blanching temperature increased. Specifically, the lignin content of bamboo shoots decreased from 5.59% to 4.58% with an increase in HHAIB blanching time from 2 to 10 min and dropped from 5.48% to 4.63% as HHAIB blanching temperature increased from 80 to 85°C, respectively. The lignin content was proved to be positively correlated (p < 0.05) with texture attributes (brittleness and chewiness). A second polynomial model was obtained for fitting the variation kinetics of lignin content during thermal processing. Reducing the HHAIB blanching time and blanching temperature would obtain a lower weight loss and a better color performance (ΔE and L*). Additionally, microstructure observation revealed that the distribution density of microchannels initially increased and then decreased with the extension of blanching time, while it continuously became firmer as HHAIB blanching temperature increased. Overall, the optimal processing parameters were achieved under the HHAIB blanching temperature of 85°C for 6 min, ensuring a high-quality performance of bamboo shoot products.

Enhanced mass transfer of pulsed vacuum pressure pickling and changes in quality of sour bamboo shoots.

Sour bamboo shoot is a traditional Chinese fermented vegetable food. The traditional pickling method of sour bamboo shoots has the disadvantages of being time-consuming, inhomogeneous, and difficult to control. Pulsed vacuum pressure pickling (PVPP) technology uses pulsed vacuum pressure to enhance the pickling efficiency significantly. To demonstrate the effects of salt content and PVPP technical parameters on the fermentation of bamboo shoots, the sample salinity, pH value, color, crunchiness and chewiness, nitrite content, and lactic acid bacteria content during the pickling process were investigated. The salt content inside the bamboo shoots gradually increased to the equilibrium point during the pickling process. The pickling efficiency of bamboo shoots under PVPP technology increased by 34.1% compared to the traditional control groups. Meanwhile, the uniform salt distribution under PVPP technology also obtained better performance in comparison with the traditional groups. The pH value declined slowly from 5.96 to 3.70 with the extension of pickling time and sour flavor accumulated progressively. No significant differences were found in the color values (L *, a *, and b *) and the crunchiness of the bamboo shoot under different salt solution concentrations, vacuum pressure, and pulsation frequency ratio conditions. Colony-forming unit of lactic acid bacteria (CFU of LAB) decreased, to begin with, and then increased until the 6th day, followed by a declining trend in volatility. The nitrate content of bamboo shoots samples under PVPP treatments did not exceed the safety standard (<20 mg/kg) during the whole fermentation process, which proves the safety of PVPP technology. In conclusion, PVPP technology can safely replace the traditional method with better quality performance. The optimal PVPP processing conditions (vacuum pressure 60 kPa, 10 min vacuum pressure time vs. 4 min atmospheric pressure time, salt solution concentration 6%) have been recommended for pickling bamboo shoots with high product quality.

Vascular endothelial growth factor activates neural stem cells through epidermal growth factor receptor signal after spinal cord injury.

AIMS: Neural stem cells (NSCs) in the adult mammalian spinal cord are activated in response to spinal cord injury (SCI); however, mechanisms modulating this process are not clear. Here, we noticed SCI elevated expression of vascular endothelial growth factor (VEGF) and we aimed to validate the roles of VEGF in NSCs activation after SCI and investigated the related signals during the process. METHODS: In vitro we detected whether VEGF promoted spinal cord NSCs proliferation and investigated the involved signals; In vivo, we injected VEGF into rat spinal cord to check the NSCs activation. RESULTS: In vitro, VEGF triggered spinal cord NSCs proliferation and maintained self-renewal. Further investigations demonstrated VEGF transactivated epidermal growth factor receptor (EGFR) through VEGF receptor 2 (VEGFR2) to promote spinal cord NSCs proliferation. In vivo, we injected VEGF into spinal cord by laminectomy to confirm the roles of VEGF-VEGFR2-EGFR signals in NSCs activation. VEGF significantly elevated the number of activated NSCs and increased EGFR phosphorylation. In contrast, intraspinal injection of specific inhibitors targeting EGFR and VEGFR2 decreased NSCs activation after SCI. Our results demonstrate that VEGF-VEGFR2-EGFR axis is important for NSCs activation after SCI, providing new insights into the mechanisms of spinal cord NSCs activation postinjury.

[Effects of bone marrow mesenchymal stem cells on bleomycin induced pulmonary fibrosis in rats].

OBJECTIVE: To study the effects of bone marrow mesenchymal stem cells (MSC) on pulmonary fibrosis. METHODS: Bone marrow MSC were harvested from 6 week old male SD rats. Forty-eight female SD rats were randomly divided into six groups. The pulmonary fibrosis models were made by intratracheal instillation of bleomycin (5 mg/kg in 0.3 ml normal saline). The normal controls received intratracheal instillation of NS instead of bleomycin. On the 1st and 7th day after bleomycin administration, the rats received MSC infusion or a same amount of phosphate buffer solution (PBS) as controls via the tail vein, respectively. The rats were sacrificed by the 28 day of experiment, and the pathologic changes and hydroxyproline contents of the lung tissues were investigated. The sry gene of Y chromosome was detected by polymerase chain reaction (PCR). RESULTS: For rats receiving MSC on the 1st and 7th day after bleomycin administration, the lung fibrotic scores were 1.0 +/- 0.2 and 1.6 +/- 0.5, respectively, significantly decreased as compared with rats receiving no MSC (2.5 +/- 0.5 & 2.3 +/- 0.8, respectively). The hydroxyproline contents of lung tissue were (83 +/- 17) microg/mg and (96 +/- 20) microg/mg, also significantly decreased as compared with rats receiving no MSCs [(123 +/- 32) microg/mg & (127 +/- 34) microg/mg, respectively]. Earlier administration of MSCs resulted in more significant improvement of lung injury. The sry gene (322 bp) was detected in lungs of female rats receiving MSC on the first day of bleomycin induced lung injury. CONCLUSIONS: MSC may be involved in the repair of lung injury, especially in the early stage. MSCs are effective in preventing bleomycin induced lung injury and fibrosis.

Expression of human BMP-2 gene in different tissues of tobacco plants.

The bone morphogenetic proteins (BMPs) are a family of growth factors that regulate the development of bone. BMP-2 is the most effective in the induction of bone tissue. A large amount of BMP-2 is needed for both bone tissue engineering research and clinical application. Thus, an effective way is necessary to produce sufficient BMP-2 protein. With the advance in plant biotechnology, transgenic plants have been targeted as a bioreactor to produce desired recombinant proteins. Here, the expression of recombinant human bmp-2 gene (rhbmp-2) was studied in tobacco plants using gus as a reporter gene. The difference of expression levels in root, stem and leaf tissues was analyzed by GUS activity assay, semi-quantitive RT-PCR and western blotting.The results indicated that the expression levels of fusion protein in root and stem tissues were significantly higher than those in leaf tissue. For the protein compositions in root and stem tissues were simpler than those in leaf tissue,this suggested that the purification process with root and stem tissues would potentially be easier.

Glycolysis-dependent histone deacetylase 4 degradation regulates inflammatory cytokine production.

Activation of the inflammatory response is accompanied by a metabolic shift to aerobic glycolysis. Here we identify histone deacetylase 4 (HDAC4) as a new component of the immunometabolic program. We show that HDAC4 is required for efficient inflammatory cytokine production activated by lipopolysaccharide (LPS). Surprisingly, prolonged LPS treatment leads to HDAC4 degradation. LPS-induced HDAC4 degradation requires active glycolysis controlled by GSK3ß and inducible nitric oxide synthase (iNOS). Inhibition of GSK3ß or iNOS suppresses nitric oxide (NO) production, glycolysis, and HDAC4 degradation. We present evidence that sustained glycolysis induced by LPS treatment activates caspase-3, which cleaves HDAC4 and triggers its degradation. Of importance, a caspase-3-resistant mutant HDAC4 escapes LPS-induced degradation and prolongs inflammatory cytokine production. Our findings identify the GSK3ß-iNOS-NO axis as a critical signaling cascade that couples inflammation to metabolic reprogramming and a glycolysis-driven negative feedback mechanism that limits inflammatory response by triggering HDAC4 degradation.

The promotion of neurological recovery in an intracerebral hemorrhage model using fibrin-binding brain derived neurotrophic factor.

Brain derived neurotrophic factor (BDNF) has been shown to ameliorate recovery after intracerebral hemorrhage (ICH). The injured brain tissue after ICH is surrounded by hematoma formed from hemorrhage. Fibrin is abundant in hematoma, which could be a binding target for BDNF. In this work, we have fused a fibrin-binding domain (FBD) to BDNF (FBD-BDNF), and results demonstrate that FBD-BDNF has specific binding ability to fibrin and is retained in hematoma. Using the rat ICH model induced by bacterial collagenase, injected FBD-BDNF has been concentrated and retained at the hematoma. FBD has facilitated BDNF to exert targeting neuroprotective effect to the injured brain tissue around the hematoma after ICH. FBD-BDNF has significantly reduced the hemotoma volume, reduced tissue loss, promoted neural regeneration, and improved the rat behavioral performance.