Antidepressant potential of total flavonoids from Astragalus in a chronic stress mouse model: Implications for myelination and Wnt/ß-catenin/Olig2/Sox10 signaling axis modulation.

ETHNOPHARMACOLOGICAL RELEVANCE: Radix Astragali, a versatile traditional Chinese medicinal herb, has a rich history dating back to "Sheng Nong's herbal classic". It has been employed in clinical practice to address various ailments, including depression. One of its primary active components, total flavonoids from Astragalus (TFA), remains unexplored in terms of its potential antidepressant properties. This study delves into the antidepressant effects of TFA using a mouse model subjected to chronic unpredictable mild stress (CUMS). AIMS OF THE STUDY: The study aimed to scrutinize how TFA influenced depressive behaviors, corticosterone and glutamate levels in the hippocampus, as well as myelin-related protein expression in CUMS mice. Additionally, it sought to explore the involvement of the Wnt/ß-catenin/Olig2/Sox10 signaling axis as a potential antidepressant mechanism of TFA. MATERIALS AND METHODS: Male C57BL/6 mice were subjected to CUMS to induce depressive behaviors. TFA were orally administered at two different doses (50 mg/kg and 100 mg/kg). A battery of behavioral tests, biochemical analyses, immunohistochemistry, UPLC-MS/MS, real-time PCR, and Western blotting were employed to evaluate the antidepressant potential of TFA. The role of the Wnt/ß-catenin/Olig2/Sox10 signaling axis in the antidepressant mechanism of TFA was validated through MO3.13 cells. RESULTS: TFA administration significantly alleviated depressive behaviors in CUMS mice, as evidenced by improved sucrose preference, reduced immobility in tail suspension and forced swimming tests, and increased locomotor activity in the open field test. Moreover, TFA effectively reduced hippocampal corticosterone and glutamate levels and promoted myelin formation in the hippocampus of CUMS mice. Then, TFA increased Olig2 and Sox10 expression while inhibiting the Wnt/ß-catenin pathway in the hippocampus of CUMS mice. Finally, we further confirmed the role of TFA in promoting myelin regeneration through the Wnt/ß-catenin/Olig2/Sox10 signaling axis in MO3.13 cells. CONCLUSIONS: TFA exhibited promising antidepressant effects in the CUMS mouse model, facilitated by the restoration of myelin sheaths and regulation of corticosterone, glutamate, Olig2, Sox10, and the Wnt/ß-catenin pathway. This research provides valuable insights into the potential therapeutic application of TFA in treating depression, although further investigations are required to fully elucidate the underlying molecular mechanisms and clinical relevance.

[Effect of electroacupuncture at "Jiaji" (EX-B 2) points on the proliferation and differentiation of oligodendrocyte precursor cells in rats with acute spinal cord injury].

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Jiaji" (EX-B 2) points on the proliferation and differentiation of oligodendrocyte precursor cells in rats with acute incomplete spinal cord injury, and to explore the mechanism of EA on improving motor function of spinal cord injury. METHODS: A total of 72 male SPF SD rats were randomly divided into a sham operation group, a model group, an EA group and a medication group, 18 rats in each group. Each group was further divided into 1-day subgroup, 7-day subgroup and 14-day subgroup, 6 rats in each subgroup. The T10 acute incomplete spinal cord injury model was established by modified Allen's method in the model group, EA group and medication group. The rats in each group received intraperitoneal injection of 5-bromodeoxyuridine (BrdU, 50 mg/kg), once a day, and each subgroup received continuous injection for 1, 7, 14 times for cell proliferation labeling. The rats in the EA group were treated with EA at "Jiaji" (EX-B 2) points 3-4 mm next the spinous process of the upper and lower segments of the injured spinal cord (T9, T11) with a frequency of 2 Hz/100 Hz and intensity of 1-2 mA. The muscle twitch at the treatment site was taken as the degree. The treatment was given 20 min each time, once a day. In the medication group, monosialogangliosides (GM1) was injected intraperitoneally (10 mg/kg), once a day. The subgroups of EA group and medication group were treated for 1, 7, 14 times. The score of Basso Beattie Bresnahan (BBB) was used to evaluate the motor function of hind limbs. The co-expression of BrdU/NG2 positive cells was detected by immunofluorescence, and the expression of Olig2 and Sox10 was detected by Western blot. RESULTS: Compared with the sham operation group, the BBB score was decreased 1 day, 7 days and 14 days after operation in the model group (P<0.05), the expression of Olig2 and Sox10 was increased (P<0.05), and the co-expression of BrdU/NG2 positive cells was increased 7 days and 14 days after operation (P<0.05). Seven days and 14 days after operation, the BBB score in the EA group and medication group was higher than that in the model group (P<0.05), and the co-expression of BrdU/NG2 in the medication group was higher than that in the model group (P<0.05). Fourteen days after operation, the co-expression of BrdU/NG2 in the EA group was higher than that in the model group (P<0.05); 1 day, 7 days and 14 days after operation, the expression of Olig2 and Sox10 in the EA group and medication group was higher than that in the model group (P<0.05). Compared with the medication group, the co-expression of BrdU/NG2 positive cells in the EA group 14 days after operation was decreased (P<0.05); 1 day, 7 days and 14 days after operation, the expression of Olig2 and Sox10 in the EA group was decreased (P<0.05). CONCLUSION: EA at "Jiaji" (EX-B 2) points could promote the expression of Olig2 and Sox10 after spinal cord injury, which has similar effects with GM1. It could promote the proliferation and differentiation of oligodendrocyte precursor cells into oligodendrocytes, so as to promote the recovery of motor function of rats.

Effect of electroacupuncture at "Jiaji" (EX-B 2) points on the proliferation and differentiation of oligodendrocyte precursor cells in rats with acute spinal cord injury / 中国针灸

OBJECTIVE@#To observe the effect of electroacupuncture (EA) at "Jiaji" (EX-B 2) points on the proliferation and differentiation of oligodendrocyte precursor cells in rats with acute incomplete spinal cord injury, and to explore the mechanism of EA on improving motor function of spinal cord injury.@*METHODS@#A total of 72 male SPF SD rats were randomly divided into a sham operation group, a model group, an EA group and a medication group, 18 rats in each group. Each group was further divided into 1-day subgroup, 7-day subgroup and 14-day subgroup, 6 rats in each subgroup. The T acute incomplete spinal cord injury model was established by modified Allen's method in the model group, EA group and medication group. The rats in each group received intraperitoneal injection of 5-bromodeoxyuridine (BrdU, 50 mg/kg), once a day, and each subgroup received continuous injection for 1, 7, 14 times for cell proliferation labeling. The rats in the EA group were treated with EA at "Jiaji" (EX-B 2) points 3-4 mm next the spinous process of the upper and lower segments of the injured spinal cord (T, T) with a frequency of 2 Hz/100 Hz and intensity of 1-2 mA. The muscle twitch at the treatment site was taken as the degree. The treatment was given 20 min each time, once a day. In the medication group, monosialogangliosides (GM1) was injected intraperitoneally (10 mg/kg), once a day. The subgroups of EA group and medication group were treated for 1, 7, 14 times. The score of Basso Beattie Bresnahan (BBB) was used to evaluate the motor function of hind limbs. The co-expression of BrdU/NG2 positive cells was detected by immunofluorescence, and the expression of Olig2 and Sox10 was detected by Western blot.@*RESULTS@#Compared with the sham operation group, the BBB score was decreased 1 day, 7 days and 14 days after operation in the model group (<0.05), the expression of Olig2 and Sox10 was increased (<0.05), and the co-expression of BrdU/NG2 positive cells was increased 7 days and 14 days after operation (<0.05). Seven days and 14 days after operation, the BBB score in the EA group and medication group was higher than that in the model group (<0.05), and the co-expression of BrdU/NG2 in the medication group was higher than that in the model group (<0.05). Fourteen days after operation, the co-expression of BrdU/NG2 in the EA group was higher than that in the model group (<0.05); 1 day, 7 days and 14 days after operation, the expression of Olig2 and Sox10 in the EA group and medication group was higher than that in the model group (<0.05). Compared with the medication group, the co-expression of BrdU/NG2 positive cells in the EA group 14 days after operation was decreased (<0.05); 1 day, 7 days and 14 days after operation, the expression of Olig2 and Sox10 in the EA group was decreased (<0.05).@*CONCLUSION@#EA at "Jiaji" (EX-B 2) points could promote the expression of Olig2 and Sox10 after spinal cord injury, which has similar effects with GM1. It could promote the proliferation and differentiation of oligodendrocyte precursor cells into oligodendrocytes, so as to promote the recovery of motor function of rats.

Apoptotic Effect of Astragalin in Melanoma Skin Cancers via Activation of Caspases and Inhibition of Sry-related HMg-Box Gene 10.

Though Astragalin (kaempferol-3-glucoside) contained in Paeonia lactiflora and other plants was known to have anti-oxidant, antiinflammatory, and anti-tumor activity, the anti-tumor mechanism of Astragalin has never been reported in melanomas until now. Thus, in the present study, the underlying apoptotic mechanism of Astragalin isolated from Aceriphyllum rossii was elucidated in A375P and SK-MEL-2 melanoma cells. Astragalin exerted cytotoxicity in A375P and SK-MEL-2 cells in a concentration-dependent manner. Also, Astragalin significantly increased the number of TdT-mediated dUTP nick end labeling positive cells and sub-G1 population as a feature of apoptosis in A375P and SK-MEL-2 cells compared with untreated control. Consistently, western blotting revealed that Astragalin activated caspase 9/3 and Bax, cleaved poly (ADP-ribose) polymerase, and attenuated the expression of cyclin D1, Mcl-1, and Sry-related HMg-Box gene 10 (SOX10) in A375P and SK-MEL-2 cells. Of note, ectopic expression of SOX10 reduced the apoptotic ability of Astragalin to inhibit proliferation, cleave poly (ADP-ribose) polymerase, and caspase 3 in A375P and SK-MEL-2 melanoma cells. Overall, our findings provide evidence that Astragalin induces apoptosis in A375P and SK-MEL-2 melanoma cells via activation of caspase9/3 and inhibition of SOX10 signaling. Copyright © 2017 John Wiley & Sons, Ltd.

Decreased expression of myelin gene regulatory factor in Niemann-Pick type C 1 mouse.

Niemann-Pick type C 1 (NPC1) disease is an autosomal recessive cholesterol transport defect resulting in a neurodegenerative process in patients mainly at an early age, although some patients may start with manifestation in adult. Since loss of myelin is considered as a main pathogenetic factor, the precise mechanism inducing dysmylination in NPC1 disease is still unclear. In the present study, a quantitative evaluation on the myelin protein and its regulatory factors of oligodendrocytes, such as SRY-related HMG-box 10 (Sox10), Yin Yang 1 factor (YY1) and myelin gene regulatory factor (MRF), in different parts of the brain and spinal cord was performed in NPC1-mutant mice. The results showed that NPC1 protein was expressed in oligodendrocytes and the amount of myelin protein was generally decreased in all parts of the brain and spinal cord in NPC1-mutant mice. Compared to wild type, the amount of Sox10 and YY1 was not different in NPC1-mutant mice, but MRF was significantly decreased, suggesting a possible mechanism perturbing differentiation of oligodendrocytes and the myelination process in the NPC1-mutant mouse.

A role for foxd3 and sox10 in the differentiation of gonadotropin-releasing hormone (GnRH) cells in the zebrafish Danio rerio.

Gonadotropin-releasing hormone (GnRH) is found in a wide range of vertebrate tissues, including the nervous system. In general, GnRH has two functions: endocrine, acting as a releasing hormone; and neuromodulatory, affecting neural activity in the peripheral and central nervous system. The best understood population of GnRH cells is that of the hypothalamus, which is essential for reproduction. Less well understood are the populations of GnRH cells found in the terminal nerve and midbrain, which appear to be neuromodulatory in function. The GnRH-containing cells of the midbrain are proposed to arise from the mesencephalic region of the neural tube. Previously, we showed that neuromodulatory GnRH cells of the terminal nerve arise from cranial neural crest. To test the hypothesis that neuromodulatory GnRH cells of the midbrain also arise from neural crest, we used gene knockdown experiments in zebrafish to disrupt neural crest development. We demonstrate that decrement of the function of foxd3 and/or sox10, two genes important for the development and specification of neural crest, resulted in a reduction and/or loss of GnRH cells of the midbrain, as well as a reduction in the number of terminal nerve GnRH cells. Therefore, our data support a neural crest origin for midbrain GnRH cells. Additionally, we demonstrate that knockdown of kallmann gene function resulted in the loss of endocrine GnRH cells of the hypothalamus, but not of neuromodulatory GnRH cells of the midbrain and terminal nerve, thus providing additional evidence for separate pathways controlling the development of neuromodulatory and endocrine GnRH cells.

Activation of myelin genes during transdifferentiation from melanoma to glial cell phenotype.

Induction of myelin genes occurs around birth in the last stage of Schwann cells differentiation and is reactivated in case of nerve injury. Previous studies showed that activation of the gp130 receptor system, using as ligand interleukin-6 fused to its soluble receptor (IL6RIL6), causes induction of myelin genes such as myelin basic protein (MBP) and myelin protein zero (Po) in embryonic dorsal root ganglia Schwann cells. We also reported that in murine melanoma B16/F10.9 cells, IL6RIL6 causes a shut-off of melanogenesis mediated by a down-regulation of the paired-homeodomain factor Pax3. The present work demonstrates that these IL6RIL6-treated F10.9 cells undergo transdifferentiation to a myelinating glial phenotype characterized by induction of the transcriptional activities of both Po and MBP promoters and accumulation of myelin gene products. For both Po and MBP promoters, a repression by Pax3 and stimulation by Sox10 can be demonstrated. Because after IL6RIL6-treatment, Pax3 disappears from the F10.9 cells (as it does in mature myelinating Schwann cells) whereas the level of Sox10 rather increases, we modulated the relative level of these factors and show their involvement in the induction of myelin gene expression by IL6RIL6. In addition, however, we show that a C/G-rich CACC box in the Po promoter is required for activation by IL6RIL6, as well as by ectopic Sox10, and identify a Kruppel-type zinc finger factor acting through this CACC box, which stimulates Po promoter activity.