The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a serious impact on global public health and the economy. SARS-CoV-2 infiltrates host cells via its surface spike protein, which binds to angiotensin-converting enzyme 2 on the host cell membrane. As a result, small molecules targeting spike protein have emerged as a hotspot in anti-SARS-CoV-2 drug research. Activity screening is an important step in seeking small molecule drugs. Therefore, this article aims to review the biological activity evaluation methods of small molecule inhibitors targeting SARS-CoV-2 spike protein, with the goal of laying the foundation for the discovery of new anti-SARS-CoV-2 drugs.

Objective To study the microscopic structure and morphological characteristics of Zebrafish eyeball and retina at different developmental stages, and to lay a foundation for visual research model. Methods Select eight groups of zebrafish at different ages, with six fish in each group, 48 fish in total. Optical microscopy and transmission electron microscopy were used to observe the eyeball structure of Zebrafish at different developmental stages, and the thickness of retinal each layer was measured to analyze the temporal and spatial development pattern. The morphological characteristics of various cells in the retina and the way of nerve connection were observed from the microscopic and ultrastructural aspects, especially the structural differences between rod cells and cone cells. Results The retina of Zebrafish can be divided into ten layers including retinal pigment epithelial layer, rod cells and cone cells layer, outer limiting membrane, outer nuclear layer, outer plexiform layer, inner nuclear layer, inner plexiform layer, ganglion cell layer, nerve fiber layer, inner limiting membrane. Rod cells had a smaller nucleus and a higher electron density than cone cells. Photoreceptor terminals were neatly arranged in the outer plexiform layer, forming neural connections with horizontal cells and bipolar cells, and several synaptic ribbons are clearly visible within them. In Zebrafish retina, ganglion cell layer and inner plexiform layer are the earliest developed. With the growth and development of Zebrafish, the thickness of rod cells and cone cells layer and retinal pigment epithelial layer gradually increases, and the retinal structure was basically developed in about 10 weeks. Conclusion The retinal structure of Zebrafish is typical, with obvious stratification and highly differentiated nerve cells. There are abundant neural connections in the outer plexiform layer. The ocular development characteristics of Zebrafish are similar to those of most mammals.

ObjectiveProtein arginine methyltransferases (PRMTs) play pivotal roles in numerous cellular biological processes. However, the precise regulatory effects of PRMTs on the fate determination of mesenchymal stromal/stem cells (MSCs) remain elusive. Our previous studies have shed light on the regulatory role and molecular mechanism of PRMT5 in MSC osteogenic differentiation. This study aims to clarify the role and corresponding regulatory mechanism of PRMT7 during the adipogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). Methods(1) Human bone marrow-derived mesenchymal stem cells (hBMSCs) were cultured in a medium that induces adipogenesis. We used qRT-PCR and Western blot to monitor changes in PRMT7 expression during adipogenic differentiation. (2) We created a cell line with PRMT7 knocked down and assessed changes in PRMT7 expression and adipogenic capacity using Oil Red O staining, qRT-PCR and Western blot. (3) We implanted hBMSCs cell lines mixed with a collagen membrane subcutaneously into nude mice and performed Oil Red O staining to observe ectopic lipogenesis in vivo. (4) A cell line overexpressing PRMT7 was generated, and we examined changes in PRMT7 expression using qRT-PCR and Western blot. We also performed Oil Red O staining and quantitative analysis after inducing the cells in lipogenic medium. Additionally, we assessed changes in PPARγ expression. (5) We investigated changes in insulin-like growth factor 1 (IGF-1) expression in both PRMT7 knockdown and overexpressing cell lines using qRT-PCR and Western blot, to understand PRMT7’s regulatory effect on IGF-1 expression. siIGF-1 was transfected into the PRMT7 knockdown cell line to inhibit IGF-1 expression, and knockdown efficiency was confirmed. Then, we induced cells from the control and knockdown groups transfected with siIGF-1 in lipogenic medium and performed Oil Red O staining and quantitative analysis. Finally, we assessed PPARγ expression to explore IGF-1’s involvement in PRMT7’s regulation of adipogenic differentiation in hBMSCs. Results(1) During the adipogenesis process of hBMSCs, the expression level of PRMT7 was significantly reduced (P<0.01). (2) The adipogenic differentiation ability of PRMT7 knockdown group was significantly stronger than that of control group (P<0.001). (3) The ectopic adipogenic differentiation ability of PRMT7 knockdown group was significantly stronger than that of control group. (4) The adipogenic differentiation ability of the PRMT7 overexpression group was significantly weaker than that of the control group (P<0.01). (5) The expression level of IGF-1 increased after PRMT7 knockdown (P<0.000 1). The expression level of IGF-1 decreased after PRMT7 overexpression (P<0.000 1), indicating that PRMT7 regulates the expression of IGF-1. After siIGF-1 transfection, the expression level of IGF-1 in all cell lines decreased significantly (P<0.001). The ability of adipogenic differentiation of knockdown group transfected with siIGF-1 was significantly reduced (P<0.01), indicating that IGF-1 affects the regulation of PRMT7 on adipogenic differentiation of hBMSCs. ConclusionIn this investigation, our findings elucidate the inhibitory role of PRMT7 in the adipogenic differentiation of hBMSCs, as demonstrated through both in vitro cell-level experiments and in vivo subcutaneous transplantation experiments conducted in nude mice. Mechanistic exploration revealed that PRMT7’s regulatory effect on the adipogenic differentiation of hBMSCs operates via modulation of IGF-1 signaling pathway. These collective findings underscore PRMT7 as a potential therapeutic target for fatty metabolic disorders, thereby offering a novel avenue for leveraging PRMT7 and hBMSCs in the therapeutic landscape of relevant diseases.

ObjectiveGastric cancer (GC) seriously affects human health and life, and research has shown that it is closely related to the serine/glycine metabolism. The proliferation ability of tumor cells is greatly influenced by the metabolism of serine and glycine. The aim of this study was to investigate the molecular mechanism of serine/glycine metabolism can affect the proliferation of gastric cancer cells. MethodsIn this work, a stable metabolic dynamic model of gastric cancer cells was established via a large-scale metabolic network dynamic modeling method in terms of a potential landscape description of stochastic and non-gradient systems. Based on the regulation of the model, a quantitative analysis was conducted to investigate the dynamic mechanism of serine/glycine metabolism affecting the proliferation of gastric cancer cells. We introduced random noise to the kinetic equations of the general metabolic network, and applied stochastic kinetic decomposition to obtain the Lyapunov function of the metabolic network parameter space. A stable metabolic network was achieved by further reducing the change in the Lyapunov function tied to the stochastic fluctuations. ResultsDespite the unavailability of a large number of dynamic parameters, we were able to successfully construct a dynamic model for the metabolic network in gastric cancer cells. When extracellular serine is available, the model preferentially consumes serine. In addition, when the conversion rate of glycine to serine increases, the model significantly upregulates the steady-state fluxes of S-adenosylmethionine (SAM) and S-adenosyl homocysteine (SAH). ConclusionIn this paper, we provide evidence supporting the preferential uptake of serine by gastric cancer cells and the important role of serine/glycine conversion rate in SAM generation, which may affect the proliferation ability of gastric cancer cells by regulating the cellular methylation process. This provides a new idea and direction for targeted cancer therapy based on serine/glycine metabolism.

Tranexamic acid is widely used in joint orthopedic surgery.At the same time,it has high safety and few adverse drug reactions.It can effectively improve intraoperative bleeding and promote early functional recovery of patients.This article reviews the mode of administration,safe dose,administration time and adverse drug reactions of tranexamic acid in the perioperative period of joint replacement and arthroscopic surgery,in order to provide reference for the clinical application of tranexamic acid.

Objective To investigate the effect and mechanism of tetramethylpyrazine(TMP)on cognitive function in mice with post-traumatic stress disorder(PTSD).Methods The mice were randomly divided into normal group,model group and experimental group.Except for the normal group,the PTSD mouse model was established by single prolonged stress(SPS).The experimental group was intraperitoneally injected with 10 mg·kg-1 TMP,and the normal group and the model group were intraperitoneally injected with an equal amount of 0.9％NaCl.The Morris water maze,open field and elevated plus maze tests were used to evaluate the cognitive behavior of the mice.The apoptosis of neurons was detected by Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL).The expression of ionized calcium binding adapter molecule-1(Iba-1)protein was detected by immunofluorescence(ICC).The content of oxidative stress inflammatory factors was detected by enzyme-linked immunosorbent assay(ELISA).Results The escape latency of the normal group,model group,and TMP group were(56.50±9.89),(87.16±10.48)and(68.63±10.19)s,respectively;the corner residence time of the open field were(190.37±40.64),(260.39±40.54)and(218.63±38.27)s,respectively;the apoptosis rates were(18.28±2.35)％,(39.36±3.65)％and(30.74±3.58)％,respectively;the fluorescence intensities of Iba-1 were(8.01±2.23)％,(50.87±7.31)％and(7.49±1.41)％;malondialdehyde contents were(5.46±0.95),(12.98±2.06)and(8.31±1.28)nmol·mg-1,respectively;tumor necrosis factor-α contents were(53.59±9.91),(115.46±11.53)and(74.38±10.77)pg·mL-1,respectively.The above indexes in the normal group and the experimental group were statistically significant compared with the model group(P＜0.05,P＜0.01).Conclusion TMP can improve the cognitive function of PTSD mice,and the mechanism may be related to the regulation of inflammation and oxidative stress.

AIM To explore the effects of Zishui Qinggan Decoction on the mouse model of depression induced by chronic restraint stress(CRS)via ERK/GSK3β/CREB/BDNF signaling pathway.METHODS Except for those of the blank group,the mice of other groups were induced into depression models by CRS,and divided into the model group,the fluoxetine hydrochloride group(10 mg/kg)and the low,medium and high dose Zishui Qinggan Decoction groups(8.835,17.670 and 35.340 g/kg)for the corresponding drug intervention and simultanous CRS treatment.The mice had their sugar water preference experiment and behavior experiment on the 7th and 14th day after administration;the observation of the hippocampal morphological changes by HE staining,the detection of the superoxide dismutase(SOD)activity and malondialdehyde(MDA)level in serum by kits,the detection of levels of serum 5-hydroxytryptamine(5-HT),tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β)by ELISA,the detection of the hippocampal mRNA expressions of BDNF,TNF-α and IL-1β by RT-qPCR method,and the detection of the hippocampal protein expressions of ERK1/2,p-ERK1/2,GSK3β,p-GSK3β,CREB and BDNF by Western blot method 14 days after administration.RESULTS Compared with the model group,after 14 days of administration,both fluoxetine hydrochloride group and medium-dose Zishui Qinggan Decoction group displayed increased preference rate of sugar water(P<0.01),shortened immobility time of tail suspension and forced swimming(P<0.01),improved hippocampal damage of nerve cells,decreased levels of serum MDA,TNF-α and IL-1β(P<0.05,P<0.01),increased SOD activity and 5-HT level(P<0.05,P<0.01),decreased hippocampal mRNA expressions of TNF-α and IL-1β(P<0.01),and decreased expressions of BDNF mRNA and p-ERK1/2,p-GSK3β,CREB and BDNF proteins(P<0.05,P<0.01).CONCLUSION Zishui Qinggan Decoction can improve the depression-like behaviors in mice exposed to CRS,and its mechanism may be related to the regulation of hippocampal ERK/GSK3β/CREB/BDNF signaling pathway.

OBJECTIVE To investigate the pharmacokinetic characteristics of crossbow microemulsion in rabbit skin.METH-ODS The concentrations of chlorogenic acid,benzoyl new aconitine,periplocin and new aconitine were determined by UPLC.The effects of temperature,perfusion speed and mass concentration on the recovery rate of the probe were investigated by incremental and decrement methods,the changes of multi-component content in the dialysate at different time points after transdermal administration of crossbow microemulsion were determined by UPLC,and DAS 2.0 software was used to process the data.RESULTS The recovery rate of the probe increased with increasing temperature,and the higher the flow rate,the lower the recovery rate.The pharmacokinetic parameters of chlorogenic acid,benzoyl new aconitine,periplocin and new aconitine in microemulsion Cmax were(3.24±0.39)(1.04±0.29)(4.78±2.15)(2.86±0.55)μg·mL-1,respectively,and in AUC0-∞ were(52.42±30.84)(7.70±3.73)(42.23±13.93)(22.68±12.51)h·mg·mL-1,respectively.CONCLUSION A real-time in vivo microdialysis sampling technique was first used and a UPLC detection technique was established to study the skin pharmacokinetics of multi-components of crossbow microe-mulsion after transdermal administration,which provides a reference for the follow-up investigation and application of crossbow microe-mulsion.

Orodispersible films (oral dispersible films), a novel form of oral solid dosage forms, are widely used for patients with dysphagia and those with uncontrollable autonomic behavior. In this study, suvorexant orodispersible film was prepared by hot melt extrusion technology, and the disintegration time, mechanical properties, in vitro dissolution and pharmacokinetics were evaluated, compared with other orodispersible films and commercially available tablets Belsomra. All experiments were approved by the Committee on the Management and Use of Laboratory Animals of Academy of Military Medical Sciences (IACUC-DWZX-2024-504). The results showed that the dissolution rate of suvorexant orodispersible film was faster and the mechanical strength was better than that of other commercially available orodispersible film, which could meet the needs of storage and transportation. Differential scanning calorimetry and X-ray diffraction results showed that suvorexant was dispersed within the orodispersible film in an amorphous state. The in vitro dissolution of the film was observed to be four times faster than that of the commercial tablets, achieving complete dissolution within five minutes. Pharmacokinetic evaluations in Beagle dogs revealed that the self-formulated orodispersible film exhibited no significant differences in the area under the blood concentration-time curve when compared with Belsomra. However, the film showed a faster onset of action, with a peak time that was twice as rapid, and a maximum blood concentration that was twice as high as that of Belsomra. Leveraging hot melt extrusion technology, the suvorexant orodispersible film offers a straightforward, continuous production process with consistent quality. It serves as an excellent platform for the development of solvent-free film preparations tailored for patients with special needs.

The rheological properties of drug and carrier materials have a wide range of guiding significance for the formulation and process development of solid dispersions. In this study, the rheological properties of materials with different drug carrier ratios were systematically studied with suvorexant as the model drug and copovidone as the carrier material, which provided a sufficient basis for determining the formulation and process of solid dispersions. The optimal suvorexant-copovidone ratio obtained by oscillating temperature scanning was 1∶4. If the ratio is greater than 1∶ 4, the glass transformation temperature of the material will increase significantly, and the solubilization effect of the solid dispersion will show a downward trend. The results of oscillation temperature scanning and oscillation temperature sweep can show that when the extrusion temperature is greater than 150 ℃, the viscosity of the material is less than 10 000 Pa·s, and the melt can be extruded smoothly, and the best extrusion temperature of 160-180 ℃ can be obtained by combining the dissolution results. Finally, the dissolution of suvorexant tablets guided by rheological property studies in multiple media is similar to that of the commercially available tablets Belsomra. Therefore, rheological studies can screen and optimize the formulation and process of suvorexant solid dispersions at the mechanism level, which is of great significance to improve the success rate of R&D and shorten the R&D cycle of solid dispersions prepared by hot melt extrusion.