Network pharmacology analysis and experimental validation to explore the effect and mechanism of tetramethylpyrazine for spinal cord injury.

OBJECTIVE: To investigate the effect and mechanism of Tetramethylpyrazine (TMP) in treating Spinal Cord Injury (SCI) using network pharmacology analysis and animal experiments. METHODS: This study was based on public databases, including PharmMapper, BATMAN-TCM, and STRING, as well as KEGG pathway analysis and other methods of network pharmacology were used to preliminarily explore the molecular mechanism of TMP in the treatment of SCI. Using a mouse SCI compression injury model, the efficacy of TMP was evaluated, and the expression of predictive targets on the PI3K/AKT and MAPK signaling pathways was measured using Western blotting and q-PCR. RESULTS: Network pharmacology analysis showed that TMP may exert therapeutic effects through the MAPK and PI3K/AKT signaling pathways. In animal experimental validation studies, it was shown that after treatment with TMP, the hind limb motor function scores and ramp test scores of the TMP-treated mice improved significantly. HE staining showed that after treatment with TMP, cavities decreased, fewer glial cells proliferated, and fewer inflammatory cells infiltrated; Nielsen staining showed less neuronal loss. Western blot studies showed that compared with the model group, expression of RAS, ERK1/2, RAF1, PI3K, and p-AKT proteins in the spinal cord tissue of mice treated with high-dose TMP was significantly lower. Accordingly, q-PCR studies showed that compared with the model group, the expression levels of RAS, ERK1/2, RAF1, PI3K, and p-AKT genes in the spinal cords of mice in the high-dose TMP group were significantly lower. CONCLUSION: TMP exhibits a good neuroprotective effect after SCI, which may be related to inhibition of the MAPK and PI3K/AKT signaling pathways.

321 W high-efficiency continuous-wave green laser produced by single-pass frequency doubling of narrow-linewidth fiber laser.

In this study, a high-power continuous-wave green laser for copper processing is investigated. The laser is produced by single-pass second-harmonic generation (SHG) of a narrow-linewidth fiber laser. Based on Sellmeier equations, the factors (e.g., fundamental wave linewidth, temperature, and angle) that decide LBO noncritical phase matching are theoretically analyzed for optimizing the SHG setup. A narrow-linewidth polarization-maintained fiber laser is used as the fundamental laser with a linewidth of 20 GHz and polarization extinction ratio of greater than 15 dB. Type I noncritical phase-matching LBO is used as the nonlinear crystal in the SHG. A green laser (up to 321 W) is obtained from a 784 W fundamental laser with a conversion efficiency of 40.9%. The green laser is near-diffraction-limited and has a $ M^{2} $ factor of 1.07.

Delivery of CW laser power up to 300 watts at 1080†nm by an uncooled low-loss anti-resonant hollow-core fiber.

In this paper, we report the use of a 3-meter low-loss anti-resonant hollow-core fiber (AR-HCF) to deliver up to 300 W continuous-wave laser power at 1080 nm wavelength from a commercial fiber laser source. A near-diffraction-limited beam is measured at the output of the AR-HCF and no damage to the uncooled AR-HCF is observed for several hours of laser delivery operation. The limit of AR-HCF coupling efficiency and laser-induced thermal effects that were observed in our experiment are also discussed.

[Effect of icaritin on proliferation and apoptosis of human ovarian cancer cells SKOV3].

Based on the PI3K/Akt signaling pathway, this study aimed to observe the proliferation and apoptosis of ovarian cancer SKOV3 cells at different concentrations of icaritin, in order to explore the possible molecular mechanisms. The research object was ovarian cancer SKOV3 cells. The cells were divided into the control group and icaritin groups(5, 10, 20 µmol·L~(-1)), and administrated with drugs for 48 hours. The cell counting kit-8(CCK-8)assay was used to detect the inhibitory effect of icaritin on the proliferation of ovarian cancer SKOV3 cells. The proliferation ability of the SKOV3 cells was detected by EdU assay. Hoechst 33342 fluorescence staining was used to observe the apoptotic morphology of SKOV3 cells in each group. The distribution of cell cycle and the apoptosis rate of each group were detected by flow cytometry. Quantitative Real-time PCR was used to detect mRNA expressions of PTEN, PI3K, Akt in each group of cells. Protein expressions of PTEN, PI3K, Akt and p-Akt were measured by Western blot. The results showed that the cell inhibition rates of icaritin groups were significantly increased compared with the control group(P<0.05). The rates of EdU-positive cells of icaritin groups were significantly decreased(P<0.05). SKOV3 cells in icaritin groups showed morphological changes of apoptosis. Apoptosis rates of icaritin groups were significantly increased(P<0.05). The proportions of cells in G_0/G_1 phase of icaritin groups were decreased(P<0.05), while the proportions of S phase cells were increased(P<0.05). The gene and protein expressions of PTEN in icaritin groups were elevated(P<0.05). The gene expressions of PI3K and Akt in icaritin groups were down-regulated(P<0.05). The protein expression of PI3K and p-Akt in icaritin groups were reduced(P<0.05). These results indicated that icarin may inhibit the proliferation of ovarian cancer SKOV3 cells in vitro, induce cell apoptosis and affect the cycle distribution of cells by inhibiting the PI3K/Akt signaling pathway.

Mangiferin promotes intestinal elimination of uric acid by modulating intestinal transporters.

Increasing evidence shows that the intestinal tract plays an important role in maintaining urate homeostasis and might be a potential therapeutic target for hyperuricaemia. However, uric acid-lowering drugs available in the clinic do not target intestinal excretion as a therapeutic strategy. We previously reported that mangiferin had potent hypouricaemic effects in hyperuricaemic animals. However, the underlying mechanisms are not completely clear. Here, we investigated the effects of mangiferin on the intestinal excretion of urate and its underlying mechanisms. The data revealed that mangiferin concentration-dependently promoted the intestinal secretion of endogenous urate in in situ intestinal closed loops in normal and hyperuricaemic mice, as well as inhibited the absorption of exogenous uric acid perfused into the intestinal loops in rats. Administration of mangiferin not only decreased the serum urate levels in the hyperuricaemic mice but also increased the protein expression of ATP-binding cassette transporter, subfamily G, member 2 (ABCG2) and inhibited the protein expression of glucose transporter 9 (GLUT 9) in the intestine. These findings suggested that intestinal ABCG2 and GLUT9 might be pivotal and possible action sites for the observed hypouricaemic effects. Moreover, no significant changes in intestinal xanthine oxidoreductase activities were observed, suggesting that mangiferin did not affect intestinal uric acid generation in the hyperuricaemic mice. Overall, promoting intestinal elimination of urate by upregulating ABCG2 expression and downregulating GLUT9 expression might be an important mechanism underlying mangiferin lowering serum uric acid levels. Mangiferin supplementation might be beneficial for the prevention and treatment of hyperuricaemia.

Narrow-linewidth all-fiber amplifier with up to 3.01 kW output power based on commercial 20/400 µm active fiber and counterpumped configuration.

A multikilowatt all-fiber amplifier with narrow spectral linewidth is investigated by using commercial 20/400 µm active fiber due to its more extensive application prospects. Stimulated Brillouin scattering (SBS) is suppressed effectively by combining multiple approaches including optimizing linewidth-broadened seed, shortening fiber length, and a counterpumped configuration. Consequently, the output power is pushed up to 3.01 kW with M2=1.17, and the linewidth is maintained at 48 GHz. The detailed characteristics of SBS are presented and analyzed in the frequency and time domains as output power is gradually raised. A high optical-to-optical efficiency is obtained with 85.6% and amplified spontaneous emission is reduced to 40 dB with respect to a laser signal. The proposed architecture reaches a relatively high output power with excellent beam quality under the condition of the equivalent linewidth for the commercial 20/400 µm active fibers in robustly all-fiberized structures.