Kaempferol promotes the osteogenesis in rBMSCs via mediation of SOX2/miR-124-3p/PI3K/Akt/mTOR axis.

BACKGROUND: It is reported that the osteogenesis in bone marrow mesenchymal stem cells (BMSCs) can alleviate osteoporosis progression. It has been found that Kae can promote the osteogenesis in BMSCs. However, the mechanism by which Kae mediates the osteogenesis in BMSCs is largely unknown. METHODS: RBMSCs were collected from rats. The cytotoxicity of Kae was detected by CCK-8 assay. The osteogenic calcification in rBMSCs was measured by alizarin red staining, and ALP staining was performed to test the ALP activity in rBMSCs. The binding relationship between SOX2 and miR-124-3p was explored by dual luciferase report assay and Chromatin Immunoprecipitation (ChIP). RT-qPCR and western blot were performed to assess mRNA and protein levels, respectively. RESULTS: Kae (10 µM) significantly increased the calcification, ALP activity, SOX2 level, activated PI3K/Akt/mTOR signaling and inhibited miR-124-3p level in rBMSCs, while knockdown of SOX2 reversed this phenomenon. Meanwhile, SOX2 suppressed the transcription of miR-124-3p, and SOX2 promoted the osteogenic differentiation in rBMSCs via regulation of miR-124-3p. MiR-124-3p could inactivate PI3K/Akt/mTOR to inhibit the osteogenic differentiation. CONCLUSION: Kae significantly promoted the osteogenesis in rBMSCs via mediation of SOX2/miR-124-3p/PI3K/Akt/mTOR axis. Thus, our study might shed new lights in exploring new methods against osteoporosis.

Post-status epilepticus treatment with the Fyn inhibitor, saracatinib, improves cognitive function in mice.

BACKGROUND: Status epilepticus (SE) is a life-threatening neurological disorder. The hippocampus, as an important area of the brain that regulates cognitive function, is usually damaged after SE, and cognitive deficits often result from hippocampal neurons lost after SE. Fyn, a non-receptor Src family of tyrosine kinases, is potentially associated with the onset of seizure. Saracatinib, a Fyn inhibitor, suppresses epileptogenesis and reduces epileptiform spikes. However, whether saracatinib inhibits cognitive deficits after SE is still unknown. METHODS: In the present study, a pilocarpine-induced SE mouse model was used to answer this question by using the Morris water maze and normal object recognition behavioral tests. RESULTS: We found that saracatinib inhibited the loss in cognitive function following SE. Furthermore, we found that the number of hippocampal neurons in the saracatinib treatment group was increased, when compared to the SE group. CONCLUSIONS: These results showed that saracatinib can improve cognitive functions by reducing the loss of hippocampal neurons after SE, suggesting that Fyn dysfunction is involved in cognitive deficits after SE, and that the inhibition of Fyn is a possible treatment to improve cognitive function in SE patients.

[An experimental research on differentiation of mesenchymal stem cells derived from children with spinal muscular atrophy into neuron-like cells].

OBJECTIVE: Spinal muscular atrophy (SMA) is an autosomal recessive neurodegenerative disease. It is characterized by selective loss of spinal cord motor neurons leading to muscle atrophy and is the result of mutation or deletion of the survival motor neuron (SMN) gene. Currently, there are no effective therapies for this disease. Stem cell therapy is a new prospect for SMA patients. This study aimed to investigate whether mesenchymal stem cells (MSCs) can be differentiated into neuron-like cells (NLCs) in SMA patients in order to provide a basis for stem cell therapy for SMA. METHODS: SMA was definitively diagnosed using polymerase chain reaction-restriction fragment length polymerphhism (PCR-RFLP). Two children without SMN1 gene deletion were used as controls. MSCs were isolated and purified from SMA patients and controls, and induced into NLCs by bFGF and baicalin. The NLCs were identified by immunofluourescence staining with NSE and NF monoclonal antibodies. RESULTS: SMA patients showed the deletion of SMN1 exon 7. The morphous and proliferative speed of MSCs between SMA patients and controls were similar. After 6-day induction, MSCs of the two groups displayed similar morphology to that of neurons, with long processes forming extensive networks. NSE and NF, the neuronal markers, were detected in the differentiated NLCs of the two groups. CONCLUSIONS: SMN1 deletion appears not to affect the proliferation and differentiation of MSCs. MSCs of SMA patients can be differentiated into NLCs.

[The expression of SMN2 gene mRNA in neuron-like cells derived from patients with spinal muscular atrophy].

OBJECTIVE: To detect the difference of SMN2 mRNA expression between the neuron-like cells (NLCs) derived from patients with spinal muscular atrophy (SMA). METHODS: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed to diagnose the patients with SMA and the controls. Mesenchymal stem cells (MSCs) were induced into neuron-like cells which become the models of neurons. The transcripts of SMN2 were testified with RT-PCR combined with sequencing. RESULTS: Two bands (266 bp and 212 bp) were found in the gel picture of RT-PCR and the band of 266 bp was the full length transcript (fl-SMN mRNA). The band of 212 bp was testified by sequencing to be deletion of the exon 7, which was the production of alternative splicing (skipping exon 7, SMNDelta7 mRNA). The expression of fl-SMN mRNA accounted for 23.2% of the total SMN mRNA in the SMA patients, being much lower than the rate in the controls (82.0%). In contrast, 76.8% of SMN gene transcripts was SMNDelta7 mRNA in the SMA patients, being much higher than the rate of 18% in the controls. CONCLUSIONS: Alternative splicing exists in SMN2 gene transcription, that is, exon 7 is skipped during the processing of SMN2 mRNA in the NLCs of SMA patients, which is one of the reasons of the full-length SMN protein lacking.