Glucose transporters (GLUTs) are pivotal membrane proteins that facilitate the passive transport of glucose into cells. However, their aberrant overexpression is closely linked to the Warburg effect and chemotherapy resistance of tumors. GLUTs are complex multi-pass transmembrane proteins that require detergents for extraction from the cell membrane during preparation. The persistent presence of detergents in the sample can disrupt lipid-protein interactions, potentially leading to conformational distortion and functional losses of GLUTs, severely hindering the research into their structures and transport mechanisms. To eliminate detergent interference and preserve its authentic conformation, this study employs nanodisc technology and utilizes the self-assembly of the membrane scaffold protein MSP1E3D1 and phospholipids to produce a biomimetic membrane environment, thereby overcoming the limitations of conventional methods. The C-terminal His10-tagged GLUT1 was heterologously expressed in the insect cell Sf9/Bac-to-Bac system, and the GLUT1-nanodisc complex was obtained after detergent solubilization, affinity chromatography purification via anti-His antibody resin, and self-assembly. The successfully reconstituted nanodisc complex was further purified by Ni-NTA affinity chromatography. Nanodisc reconstitution produced monodisperse GLUT1 particles that retained native secondary structure, as confirmed by far-UV circular dichroism (CD) spectroscopy and dynamic light scattering (DLS). Unlike conventional detergent micelles, which lack a true lipid bilayer, distort transmembrane-helix topology, and occlude ligand-binding sites, the nanodisc platform embeds GLUT1 in a phospholipid bilayer that preserves its authentic conformation while eliminating detergent interference. The resulting GLUT1-nanodisc complex is therefore a superior scaffold for high-resolution cryo-EM structural analysis, permitting detailed interrogation of the transporter's conformational cycle, its interactions with partner proteins, and downstream structure-guided, high-throughput drug screening.
Nanostructures/chemistry* ; Glucose Transporter Type 1/biosynthesis* ; Humans ; Animals ; Phospholipids/chemistry* ; Detergents/chemistry*

Spermatogenesis is a complex developmental process in which a diploid progenitor germ cell transforms into highly specialized spermatozoa. During spermatogenesis, membrane remodeling takes place, and cell membrane permeability and liquidity undergo phase-specific changes, which are all associated with the alteration of membrane lipids. Lipids are important components of the germ cell membrane, whose volume and ratio fluctuate in different phases of spermatogenesis. Abnormal lipid metabolism can cause spermatogenic dysfunction and consequently male infertility. Germ cell membrane lipids are mainly composed of cholesterol, phospholipids and glycolipids, which play critical roles in cell adhesion and signal transduction during spermatogenesis. An insight into the correlation of membrane lipids with spermatogenesis helps us to better understand the mechanisms of spermatogenesis and provide new approaches to the diagnosis and treatment of male infertility.
Cell Adhesion ; Cell Membrane ; chemistry ; Cholesterol ; chemistry ; Glycolipids ; chemistry ; Humans ; Infertility, Male ; Male ; Membrane Lipids ; chemistry ; Phospholipids ; chemistry ; Signal Transduction ; Spermatogenesis ; Spermatozoa ; cytology

To explore the effect of long-time propofol infusion on myocardial enzymes, mitochondrial cytochrome C and ATP in rabbits. 
 Methods: A total of 18 New Zealand rabbits were randomly divided into 3 groups: a control group, a propofol group and an intralipid group. The rabbits were continuously infused with 0.9% normal saline in the control group, 1% propofol in the propofol group, and 10% intralipid in the intralipid group, respectivey. The arterial blood was collected at 0, 8, 16 h and the end of experiment to examine creatine kinase (CK) and creatine kinase isoenzyme (CK-MB). In the end, the myocardial mitochondria from myocardial tissues was separated by differential centrifugation, and mitochondrial cytochrome C content and adenosine triphosphate (ATP) levels were examined by high performance liquid chromatography.
 Results: Compared with the control group, the release of cytochrome C from mitochondria were increased in the propofol group and the intralipid group (both P<0.05), but there was no significant difference between them (P>0.05). There was also no significant difference in the ATP content of the mitochondria among the 3 groups (P>0.05). The levels of CK were increased at 8, 16 and 24 h after infusion in the propofol group and the intralipid group compared with that before the infusion (all P<0.05); compared with the control group, the levels of CK were increased at 8, 16 and 24 h after infusion in the propofol group and the intralipid group (all P<0.05); compared with the intralipid group, the levels of CK were increased at 8, 16 and 24 h after infusion in the propofol group (all P>0.05); compared with the control group, the levels of CK-MB were obviously increased in the infusion of propofol for 24 h in the propofol group (P<0.05).
 Conclusion: The levels of serum CK increase after the infusion of propofol and intralipid for a long time, and the levels of CK-MB also elevate in the infusion of propofol. Propofol and intralipid can increase the release of myocardial mitochondrial cytochrome C, but they don't affect the ATP production in myocardial mitochondrial.
Adenosine Triphosphate ; metabolism ; Animals ; Creatine Kinase ; blood ; metabolism ; Creatine Kinase, MB Form ; blood ; metabolism ; Cytochromes c ; metabolism ; Emulsions ; administration & dosage ; pharmacology ; Infusions, Intravenous ; Mitochondria ; drug effects ; Myocardium ; chemistry ; enzymology ; Phospholipids ; administration & dosage ; pharmacology ; Polyphosphates ; Propofol ; administration & dosage ; pharmacology ; Rabbits ; Soybean Oil ; administration & dosage ; pharmacology

OBJECTIVETo prepare a phospholipid-coated microbubble loaded with hydrogen sulfide (HSMB) and evaluate its physicochemical and acoustic properties.

METHODSHydrogen sulfide and perfluoropropane were mixed at the ratios of 4:0, 3:1, 2:2, 1:3, and 0:4 to prepare hydrogen sulfide-loaded microbubbles (termed HSMB4:0, HSMB3:1, HSMB2:2, HSMB1:3, and HSMB0:4, respectively). The microbubble concentration and diameter were investigated and their stability were evaluated. The optimal ratio of hydrogen sulfide and perfluoropropane was determined according to the changes of microbubble concentration. The changes of dissolved hydrogen sulfide and concentration of the microbubbles were investigated after exposure to ultrasound, and their acoustic enhancement effects in the myocardium and kidney were observed after intravenous injection in rats.

RESULTSHSMBs were milky in color and spherical in shape without aggregations. The concentrations of HSMB4:0 and HSMB3:1 were lower than that of HSMB2:2 and decreased with time. HSMB2:2, HSMB1:3 and HSMB0:4 showed comparable concentrations and were stable within 72 h. After exposure to ultrasound, the concentration of HSMB2:2 decreased while the dissolved hydrogen sulfide increased significantly. Intravenous injection of HSMB2:2 produced a satisfactory contrast-enhancing effect in the myocardium and kidney of rats.

CONCLUSIONHSMB prepared with the hydrogen sulfide to perfluoropropane ratio of 2:2 has excellent contrast-enhancing effect and is capable of carrying and releasing hydrogen sulfide upon ultrasound exposure to potentially allow visual site-specific delivery of hydrogen sulfide.

Animals ; Contrast Media ; chemistry ; Fluorocarbons ; chemistry ; Heart ; Hydrogen Sulfide ; chemistry ; Kidney ; Microbubbles ; Phospholipids ; chemistry ; Rats ; Ultrasonics

The purpose of the study is to construct R8 peptide (RRRRRRRR) and pH sensitive polyethylene glycols (PEG) co-modified liposomes (Cl-Lip) and utilize them in breast cancer treatment. The co-modified liposomes were prepared with soybean phospholipid, cholesterol, DSPE-PEG2K-R8 and PEG5K-Hz-PE (pH sensitive PEG). The size and zeta potential of Cl-Lip were also characterized. The in vitro experiment demonstrated that the Cl-Lip had high serum stability in 50% fetal bovine serum. The cellular uptake of Cl-Lip under different pre-incubated conditions was evaluated on 4T1 cells. And the endocytosis pathway, lysosome escape ability and tumor spheroid penetration ability were also evaluated. The results showed the particle size of the Cl-Lip was (110.4 ± 5.2) nm, PDI of the Cl-Lip was 0.207 ± 0.039 and zeta potential of the Cl-Lip was (-3.46 ± 0.05) mV. The cellular uptake of Cl-Lip on 4T1 cells was pH sensitive, as the cellular uptake of Cl-Lip pre-incubated in pH 6.0 was higher than that of pH 7.4 under each time point. The main endocytosis pathways of Cl-Lip under pH 6.0 were micropinocytosis and energy-dependent pathway. At the same time, the Cl-Lip with pre-incubation in pH 6.0 had high lysosome escape ability and high tumor spheroid penetration ability. All the above results demonstrated that the Cl-Lip we constructed had high pH sensitivity and is a promising drug delivery system.
Animals ; Cell Line, Tumor ; Cell-Penetrating Peptides ; chemical synthesis ; chemistry ; Cholesterol ; chemistry ; Drug Delivery Systems ; Liposomes ; Mice ; Oligopeptides ; chemical synthesis ; chemistry ; Particle Size ; Phospholipids ; chemistry ; Polyethylene Glycols

The relationship of nutrients and microorganisms in soils with polyphenols and total flavonoids of Houttuynia cordata were investigated by measuring nutrients, enzyme activity, pH, concentrations of microbe phospholipid fatty acids (PLFAs) in soils, and determining concentrations of polyphenols and total flavonoids of H. cordata. The research is aimed to understand characteristics of the planting soils and improve the quality of cultivated H. cordata. The soils at different sample sites varied greatly in nutrients, enzyme activity, pH, microbic PLFAs and polyphenols and all flavonoids. The content of total PLFAs in sample sites was following: bacteria > fungi > actinomyces > nematode. The content of bacteria PLFAs was 37.5%-65.0% at different sample sites. Activities of polyphenol oxidease, concentrations of available P and content of PLFAs of bacteria, actinomyces and total microorganisms in soils were significantly and positively related to the concentrations of polyphenols and total flavonoids of H. cordata, respectively (P < 0.05) . The Content of fungi PLFAs in soils was significantly and negatively related to concentrations of polyphenols and total flavonoids of H. cordata, respectively (P < 0.05). This study provides evidence that effectiveness of the soil nutrient, which may be improved due to transformation of soil microorganisms and enzymes to N and P in the soils, was beneficial to adaptation of H. cordata adapted to different soil conditions, and significantly affects metabolic accumulation of polyphenols and flavonoids of H. cordata.
Bacteria ; metabolism ; Drugs, Chinese Herbal ; analysis ; metabolism ; Fatty Acids ; metabolism ; Flavonoids ; analysis ; metabolism ; Fungi ; metabolism ; Houttuynia ; chemistry ; metabolism ; microbiology ; Phospholipids ; metabolism ; Polyphenols ; analysis ; metabolism ; Soil ; chemistry ; Soil Microbiology

OBJECTIVE: To measure retinol binding protein 4 (RBP4) levels in serum and bile and to analyze their relationship with insulin resistance, dyslipidemia or cholesterol saturation index (CSI).
 METHODS: A total of 60 patients with gallstone were divided into a diabetes group (n=30) and a control group (n=30). The concentrations of RBP4 in serum and bile were detected by enzyme-linked immunosorbent assay (ELISA). Enzyme colorimetric method was used to measure the concentration of biliary cholesterol, bile acid and phospholipid. Biliary CSI was calculated by Carey table. Partial correlation and multiple linear regression analysis were used to evaluate the correlation between the RBP4 levels in serum or bile and the above indexes.
 RESULTS: The RBP4 concentrations in serum and bile in the diabetes group were significantly elevated compared with those in the control group (both P<0.01). There was no significant difference in the serum total bile acid (TBA), serum triglyceride (TG), serum high-density lipoprotein (HDL), bile TBA, bile total cholesterol (TC) , bile phospholipids and bile CSI between the 2 groups (all P>0.05); but the serum TC, low density lipoprotein (LDL), fasting blood glucose (FBG), fasting insulin (FINS), and homeostasis model assessment for insulin resistance (HOMA-IR) in the diabetes group were significantly increased compared to those in the control group (all P<0.05). The partial correlation analysis, which was adjusted by age, showed that the bile RBP4 was positively correlated with body mass index (BMI), waist circumference (WC), FINS, FBG, TC, LDL and HOMA-IR (r=0.283, 0.405, 0.685, 0.667, 0.553, 0.424 and 0.735, respectively), and the serum RBP4 was also positively correlated with the WC, FINS, FBG, TC, LDL and HOMA-IR (r=0.317, 0.734, 0.609, 0.528, 0.386 and 0.751, respectively). Stepwise multivariate linear regression analysis suggested that the HOMA-IR, BMI and WC were independently correlated with the level of bile RBP4 (multiple regression equation: Ybile RBP4=2.372XHOMA-IR+0.420XBMI+0.178XWC-26.813), and the serum RBP4 level was correlated with the HOMA-IR and WC independently (multiple regression equation: Yserum RBP4=2.832XHOMA-IR +0.235XWC-20.128). Multiple regression equations showed that HOMA-IR was the strongest correlation factor with RBP4.
 CONCLUSION RBP4 concentrations in serum and bile in the diabetes group are significantly higher than those in the control group. HOMA-IR, BMI and WC are independently correlated with the level of bile RBP4. HOMA-IR and WC are independently correlated with the serum RBP4 level. HOMA-IR is the strongest correlation factor with RBP4. RBP4 might play an important role in the course of gallstone formation in Type 2 diabetes mellitus.
Bile ; chemistry ; Bile Acids and Salts ; blood ; Blood Glucose ; chemistry ; Body Mass Index ; Cholesterol ; chemistry ; Diabetes Mellitus, Type 2 ; complications ; metabolism ; Enzyme-Linked Immunosorbent Assay ; Gallstones ; complications ; Humans ; Insulin ; blood ; Insulin Resistance ; Lipoproteins, HDL ; blood ; Lipoproteins, LDL ; blood ; Phospholipids ; chemistry ; Retinol-Binding Proteins, Plasma ; metabolism ; Triglycerides ; blood ; Waist Circumference

Bicyclol with benzyl alcohol structure, is a poorly water-soluble drug, used for the treatment of chronic hepatitis B. To increase the drug solubility and oral bioavailability, a Bicyclol-phospholipid complex was studied on its preparation, formation mechanism, and the influence on drug physicochemical properties and oral absorption. The complex was prepared by a solvent evaporation method. The optimal formulation was selected by orthogonal experimental design, and a reasonable evaluating method of the complexation rate was established. Various methods, such as differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and 31P nuclear magnetic resonance (31P-NMR), were used to explore the phase state and formation mechanism of the complex. The solubility of drug in complex was investigated in water/n-octanol. Preliminary study of its absorption and liver tissue distribution in rats was also carried out. The results showed that Bicyclol and phosphatidylcholine can be complexed entirely in the molar ratio 1 : 2. Bicyclol was dispersed in phospholipids as amorphous state. They were combined by intermolecular hydrogen bond due to charge transfer effect which occurred between the two polarities of the double bond between phosphorus and oxygen (P=O) of phosphatidylcholine and benzalcohol group of Bicyclol. The solubility of the complex compared to the active pharmaceutical ingredient (API) was effectively enhanced 5.75 times in water and 7.72 times in n-octanol, separately. In addition, drug concentrations were also enhanced 43 times in plasma and 13 times in liver with one hour after administering the complex to rats via oral gavage. All of these indicated that Bicyclol with benzalcohol group can interact with phospholipids to form complex, improving drug's physicochemical properties, thus further increasing its absorption and target tissue distribution. This study also provided theoretical reference for the research of other benzalcohol derivatives complexed with phospholipids.
1-Octanol ; Animals ; Biological Availability ; Biphenyl Compounds ; pharmacokinetics ; Calorimetry, Differential Scanning ; Chemistry, Pharmaceutical ; Phospholipids ; pharmacokinetics ; Rats ; Solubility ; Spectroscopy, Fourier Transform Infrared ; Tissue Distribution ; X-Ray Diffraction

Herpetin (HPT) is an active monomer constituent isolated from lignanoid in seeds of Herpetospermum caudigerum. HPT shows inhibitory effects in hepatic injury and HBV-DNA and the replication. In the study, we successfully prepare herpetin liposomes by film dispersion method for the first time. The prescription process was optimized, with the entrapment efficiency as the index. According to the optimized prescription, the mass ratio of HPT: phospholipids: cholesterol was 2.44:78.05: 19.51, the hydration and de-molding process was performed with 0.5% F68 solution at 50 degrees C, and the water-bath ultrasonic time was 20 min. The HPT liposomes prepared by this method showed an average entrapment efficiency of (94.50 +/- 2.15)% and a particle size of (119.2 +/- 10.7) nm, which was consistent with the trial expectations and will lay a solid foundation for the hepatic targeting delivery system in future.
Chemistry, Pharmaceutical ; methods ; Cholesterol ; chemistry ; Drug Compounding ; methods ; Drugs, Chinese Herbal ; chemistry ; Lignans ; chemistry ; isolation & purification ; Liposomes ; chemistry ; Phospholipids ; chemistry ; Ultrasonics

The purpose of this research was to prepare total salvianolic acids-phytosome-HA coprecipitate to improve drug dissolution and its micromeritic properties. Firstly, the coprecipitate was prepared by solvent method and in vitro dissolution of tripterine was performed with the salvianolic acid B and danshensu as criteria. At the same time, the micromeritic properties was characterizated, the structure of samples was characterized by TEM, DSC, XRD and FTIR. Results showed that when the ratio of drug to HA was 1:2, it had a better dissolution, the accumulative drug-release percent in vitro at 60 min was over 90%. At the same time, it has good liquidity and low moisture absorption. Its micromeritic properties have improved. It is proved that the drug still existed amorphously by microstructure analysis. The preparation process is simple and feasible, it has practical value.
Alkenes ; chemistry ; Chemical Precipitation ; Chemistry, Pharmaceutical ; methods ; Durapatite ; chemistry ; Phospholipids ; chemistry ; Polyphenols ; chemistry ; Time Factors