Lipid-lowering effect of drug pair Scutellariae Radix-Coptidis Rhizoma based on lipomics / 中国中药杂志

This study investigated the mechanism of action of Scutellariae Radix-Coptidis Rhizoma(SR-CR) in intervening in non-alcoholic fatty liver disease(NAFLD) in rats based on lipidomics. Thirty-six SD rats were divided into a control group, a model group, SR-CR groups of different doses, and a simvastatin group, with six rats in each group. Rats in the control group were fed on a normal diet, while those in the remaining groups were fed on a high-lipid diet. After four weeks of feeding, drug treatment was carried out and rats were sacrificed after 12 weeks. Serum liver function and lipid indexes were detected using kits, and the pathomorphology of liver tissues was evaluated by hematoxylin-eosin(HE) staining and oil red O staining. Changes in lipid levels in rats were detected using the LC-MS technique. Differential lipid metabolites were screened by multivariate statistical analysis, and lipid metabolic pathways were plotted. The changes in lipid-related protein levels were further verified by Western blot. The results showed that compared with the control group, the model group showed increased levels of alanine aminotransferase(ALT), aspartate aminotransferase(AST), total cholesterol(TC), triglyceride(TG), and low-density lipoprotein cholesterol(LDL-c)(P<0.01), and decreased levels of γ-glutamyl transferase(γ-GT) and high-density lipoprotein cholesterol(HDL-c)(P<0.01), which were significantly recovered by the intervention of SR-CR. HE staining and oil red O staining showed that different doses of SR-CR could reverse the steatosis in the rat liver in a dose-dependent manner. After lipidomics analysis, there were significant differences in lipid metabolism between the model group and the control group, with 54 lipids significantly altered, mainly including glycerolipids, phosphatidylcholine, and sphingolipids. After administration, 44 differential lipids tended to normal levels, which indicated that SR-CR groups of different doses significantly improved the lipid metabolism level in NAFLD rats. Western blot showed that SR-CR significantly decreased TG-synthesis enzyme 1(DGAT1), recombinant lipin 1(LPIN1), fatty acid synthase(FASN), acetyl-CoA carboxylase 1(ACC1), and increased the phosphorylation level of ACC1. These changes significantly decreased the synthesis of TG and increased the rate of its decomposition, which enhanced the level of lipid metabolism in the body and finally achieved the lipid-lowering effect. SR-CR can improve NAFLD by inhibiting the synthesis of fatty acids and TG.

Application of flipped classroom teaching mode supported by 3D printing model in embryology experiment teaching / 解剖学报

Objective To explore the teaching effect of flipped classroom teaching mode supported by the 3D printing model in the embryology experiment. Methods Totally 76 students from class 2016 were randomly divided into two groups: the experimental group previewed the embryo 3D models before class and taught other students in class, while the control group did not preview the embryo 3D models before class. An embryo knowledge test and a questionnaire survey were carried out before and after the experimental class to compare the differences of knowledge mastery and self-evaluation between the two groups. Results In the aspect of self-evaluation, the self-evaluation of the experimental group students in explaining the causes and explaining the process of development was significantly improved after the lecture (P<0.05), while the self-evaluation of the control group students in identifying the structure, understanding knowledge, telling the causes and explaining the process of development was significantly improved (P< 0.05). In terms of knowledge test scores, the scores of students in the experimental group and the control group after teaching were higher than those before teaching (P < 0.05). The improvement of the knowledge test in the control group was significantly higher than that in the experimental group (P<0.05). The experiment group' s grades of knowledge test were significantly higher than the control group in the second experiment. 70.27% of the students thought that they were still lack of knowledge in the introspection of the causes of wrong answers. The misunderstanding of English nouns (15.54%), psychological factors (5.41%) and other factors (8.78%) also caused the students to lose points in the knowledge tests. Conclusion The combination of the 3D printing model and the flipped classroom teaching mode can effectively improve the teaching effect, which should be paid attention to in the reform of embryology experimental teaching.

Drug synergistic antifertility effect of combined administration of low-dose gossypol with steroid hormones in rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Our previous studies suggested that low-dose gossypol combined with steroid hormones has a reversible antifertility role in adult male rats, and the course of treatment was shorter than that of either gossypol or steroid hormones alone. This result suggested that low-dose gossypol and steroid hormones have a drug synergistic effect on antifertility. The aim of the study was to find the target organs of the antifertility synergistic effect of the combined regimen.</p><p><b>METHODS</b>Thirty-two adult male rats were divided into four groups randomly: group GH, rats were fed orally with gossypol acetic acid (GA, 12.5 mg×kg(-1)×d(-1)) and desogestrel (DSG, 0.125 mg×kg(-1)×d(-1))/ethinylestradiol (EE, 0.025 mg×kg(-1)×d(-1))/testosterone undecanoate (TU, 100 mg×kg(-1)×d(-1)); group G, a single dose of GA (12.5 mg×kg(-1)×d(-1)) was given; group H, the same dosage of DSG/EE/TU as in group GH were administered; group C, rats were treated with vehicle (1% methyl cellulose) as control. Testes and epididymis were removed at 8 weeks post-treatment for evaluating their weight, volumes, volume fraction, and total volume of testicular tissue structures and the seminiferous tubule diameter using stereological assay. Sperm cell numbers and the motility of epididymal sperm were quantitated by flow cytometry and morphological methods.</p><p><b>RESULTS</b>Compared with group C, spermatogenesis was normal in group G and suppressed in groups H and GH. Similar changes of testicular tissue structures and sperm number were found in groups H and GH. The decreases of epididymal sperm number and motility in group GH were greater than that of the low-dose gossypol or steroid hormones alone group.</p><p><b>CONCLUSIONS</b>The suppression of spermatogenesis was induced by steroid hormones in the combined regimen, and the epididymis was the target organ of low-dose gossypol. Combined use of low-dose gossypol and steroid hormones played a comprehensive antifertility role in their synergistic effect on reducing the number and motility of epididymal sperm.</p>

Expression of type II collagen gene and structural change in bone tissues of rats with experimental fluorosis / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of excessive intake of fluoride on the expression of type II collagen gene and types and morphological change of collagen fiber in the bone tissues of rats.</p><p><b>METHODS</b>A rat model with fluorosis was established by adding 221 mg/L of sodium fluoride (NaF) to drinking water for the rats for 15 days, 30 days and two months, respectively. Type II collagen alpha1 (II) cDNA probe was prepared, and cDNA-mRNA in-situ hybridization was employed to detect change in expression of type II collagen mRNA in the bone tissues of rats with excessive intake of fluoride (221 mg/L NaF). Picrosirius-polarization method was used to observe types of collagen and morphology of collagen fiber in the bone tissues.</p><p><b>RESULTS</b>Chondroblasts were found in the femur and other bone tissues of the rats after exposure to fluoride. cDNA-mRNA in-situ hybridization showed that expression of type II collagen gene could be observed in the cytoplasm of chondrocytic lacuna and chondrified bone tissues. mRNA in collagen of chondrocytes of the rib cartilage reached the peak level 15 days after exposure to fluoride, and decreased gradually one month and two months after exposure. Polychromatic type II collagen, breakage of collagen fiber, disorder array and reduced content of type II collagen could be found in the bone tissues with picrosirius-polarization method.</p><p><b>CONCLUSIONS</b>Excessive intake of fluoride could lead to changes in types and structure of collagen (cross-linkage) of bone tissues, which caused expression of type II collagen gene in the chondrified bone tissues and enhanced its expression in the rib cartilage tissues.</p>