Prediction of plasma protein binding rate based on machine learning / 中国药科大学学报

@#Predicting the protein binding rate of drugs in plasma is helpful to us in understanding the pharmacokinetic characteristics of drugs, with much value of reference for early research on drug discovery. In this study, plasma protein binding rate information of 2 452 clinical drugs were collected.Two pieces of software, Molecular Operating Environment (MOE) and Mordred, were used to calculate molecular descriptors, which were used as input features of the model.Extreme gradient boosting (XGBoost) algorithm and random forest (RF) algorithm were then used to build a machine learning model.The results showed that, compared with MOE, the prediction performance of the constructed model was better using the molecular descriptor calculated by Mordred as the input of the model.The prediction performance results of the model constructed using the XGBoost algorithm and the RF algorithm were similar, and the R2 of the optimal model were both 0.715.According to the research results, it can be concluded that the drug plasma protein binding rate is closely related to some physical and chemical properties of the drug molecule, such as water solubility, octanol/water partition coefficient and conjugated double bonds.Using these parameters to predict the plasma protein binding rate of drugs has the advantages of convenience and efficiency, which can provide reference for related pharmacokinetic studies.

Determination of Plasma Protein Binding Rate of 3 Components from Glechoma longituba by UHPLC Combined with Ultrafiltration / 中国药房

OBJECTIVE：To establish a method for the determination of plasma protein binding rate of rosmarinic acid ，caffeic acid and chlorogenic acid from Glechoma longituba . METHODS ：UHPLC method combined with ultrafiltration method was adopted to determine the plasma protein binding rate of rosmarinic acid ，caffeic acid and chlorogenic acid from G. longituba in the plasma of New Zealand rabbits. The determination was performed on a Phenomenex Luna ® C18 column with mobile phase consisted of acetonitrile （A）-0.1％ formic acid solution （B）（gradient elution ）at the flow rate of 0.5 mL/min. The column temperature was set at 45 ℃，and the detection wavelength was 327 nm. The sample size was 3 μL. RESULTS：At low ，medium and high concentrations，the plasma binding rates of rosmarinic acid were （97.78 ± 1.67）％ ，（94.32 ± 1.42）％ ，（95.12 ± 1.51）％ ， respectively（n＝3）；those of caffeic acid were （90.12±2.33）％，（89.53±1.98）％，（90.23±1.56）％，respectively（n＝3）；those of chlorogenic acid were （63.23 ± 2.12）％ ，（67.87 ± 1.06）％ ，（62.34 ± 1.34）％ ，respectively （n＝3）. CONCLUSIONS ： Established method is easy to operate and shorter time for analysis. It can be used to determine the plasma protein binding rate of rosmarinic acid ，caffeic acid and chlorogenic acid in G. longituba .

Comparison of Protein Binding Rate of DPP- 4 Inhibitor LGT- 6 in Different Species of Plasma / 中国药房

OBJECTIVE：To establish the method for determining protein binding rate of dipeptidyl peptidase- 4 inhibitor LGT- 6 in different species of plasma ，and to compare their difference. METHODS ：By equilibrium dialysis ，LGT-6（3，30，300，3 000 nmol/L）was equilibrated in rat ，monkey and human plasma （i. e. internal dialysis solution ）for 48 h，using phosphate buffer as the external dialysis solution. The concentration of LGT- 6 in internal and external dialysis solution was determined by UPLC-MS/MS using tolbutamide as internal standard ，and the plasma protein binding rate was calculated. The determination was performed on ACQUITY UPLC HSS T 3 column with water （containing 0.01％ formic acid ）-acetonitrile（containing 0.01％ formic acid ）as mobile phase at the flow rate of 0.6 mL/min. The column temperature was 40 ℃，and the sample size was 2 μL. The ion source was electrospray ion source ，and the multiple ion monitoring mode was used to carry out positive ionization scanning. The ion pairs for quantitative analysis were m/z 487.0→434.3（LGT-6），m/z 271.1→172.0（internal standard ），respectively. RESULTS ：At the concentrations of 3，30，300，and 3 000 nmol/L，the protein binding rates of LGT- 6 in rat plasma were （96.25±0.97）％，（84.16± 1.24）％，（78.25±0.61）％，（66.63±0.95）％；the protein protein binding rates in monkey plasma were （98.54±0.58）％，（87.27± 1.01）％，（79.35±0.86）％，（66.69±0.54）％；the protein binding rates in human plasma were （99.40±1.03）％，（84.48± 1.15）％，（77.62±0.77）％，（66.93±0.48）％. At the same concentration ，the protein binding rates of LGT- 6 in rat ，monkey and human plasma had no significant difference （P＞0.05）. In the same species of plasma ，there were significant differences in the plasma protein binding rates of different concentration of LGT-6 among those groups （P＜0.05），and it decreased with 才〔2016〕4015） the increase of drug concentration. CONCLUSIONS ： The method for the determination of plasma protein binding rate of LGT-6 is successfully established. The data revealed that the protein binding rate of LGT- 6 is concentration-dependent ， there was no obvious spec ies difference on protein binding rates of LGT- 6 in rat ，monkey and human plasma under the same concentration.

Study on Plasma Protein Binding Rate of Cajanonic Acid A with Different Species of Plasma by Ultrafiltration Combined with UPLC-MS/MS / 中国药房

OBJECTIVE： To compare plasma protein binding rate of cajanonic acid A with different species of plasma. METHODS：Using UPLC-MS/MS as the detection means. Plasma protein binding rate of low， medium and high concentrations of cajanonic acid A （2.5， 5， 20 μg/mL） with rats， rabbits and human plasma were determined by ultrafiltration method. The chromatographic conditions included that Waters BEH C18 as chromatographic column， WatersVanGuard BEH C18 as guard column， mobile phase consisted of ultrapure water solution containing 0.01％ formic acid （solvent A） and acetonitrile solution of 0.01％ formic acid （solvent B） gradient elution， at the flow rate of 0.15 mL/min， column temperature of 30 ℃， sample size of 2 μL. Mass spectrum condition included that ESI， negative ion mode acquisition， capillary voltage of 1.5 kV， cone voltage of 30 V， ion source temperature of 100 ℃， desolvent gas temperature of 400 ℃， cone gas flow of 50 L/h， desolvent gas flow of 800 L/h， scanning range of m/z 50→1 200. RESULTS： At the concentration of 2.5， 5 and 20 μg/mL， the plasma protein binding rates of cajanonic acid A were （75.63±0.90）％， （98.30±0.03）％ and （99.42±0.01）％ in the rats plasma； （79.61±1.08）％， （98.48±0.10）％ and （99.42±0.03）％ in rabbits plasma （n＝3）； （76.74±1.22）％， （97.99±0.11）％ and （99.37±0.01）％ in human plasma （n＝3）. At the concentration of 2.5 μg/mL， plasma protein binding rates of cajanonic acid A in plasma of rats and human were significantly lower than that in plasma of rabbits （P＜0.05）. CONCLUSIONS： The plasma protein binding rate of 5，20 μg/mL cajanonic acid A with rats， rabbits and human plasma are higher than that of 2.5 μg/mL cajanonic acid A. There is significant difference in plasma protein binding rate of 2.5 μg/mL cajanonic acid A with different species of plasma，and there is no significant difference in plasma protein binding rate of 5， 20 μg/mL cajanonic acid A with different species of plasma.

Study on Compatibility Proportion of Mongolian Medicine “Terminalia chebula Decomposing Poison of Aconitum kusnezoffii ” / 中国药房

OBJECTIVE： To investigate the best compatibility proportion of Mongolian medicine “Terminalia chebula decomposing the poison of Aconitum kusnezoffii”. METHODS： Totally 40 rats were randomly divided into blank control group （0.05％ CMC-Na）， raw A. kusnezoffii group （0.12 g/kg by crude drug） and raw A. kusnezoffii-T. chebula  （1 ∶ 3，1 ∶ 1，3 ∶ 1， mass ratio） group （0.12 g/kg raw A. kusnezoffii by raw material）， 8 rats in each group. They were given relevant medicine intragastrically once a day， for consecutive 28 d. 0.5 h after last medication， serum contents of cTn-I and MB were determined， and the changes of cardiological structure were observed； the detoxification effects of T. chebula on cardiotoxicity induced by A. kusnezoffii were investigated. Binding rates of 3 kinds of aconitine （concentrations of aconitine， mesaconitine and hypaconitine were 5， 10， 20， 40， 80， 160， 400 ng/mL） to binding rate of plasma protein with normal human plasma were determined by equilibrium dialysis combined with liquid chromtography-mass spectrometry. The concentrations of 3 kinds of aconitine were fixed as 100 ng/mL. After adding main detoxification component tannic acid in different proportions of T. chebula （1 ∶ 0.025， 1 ∶ 0.075， 1 ∶ 0.1， 1 ∶ 0.5）， the effects of them on plasma protein binding rate of 3 kinds of aconitine were investigated； the possible mechanism  of T. chebula decomposing the poison of A. kusnezoffii inducing cardiotoxicity were investigated. RESULTS： In detoxification experiment， compared with blank control group， serum contents of cTn-I and MB were increased significantly in raw A. kusnezoffii group （P＜0.05）. There were obvious pathological changes in myocardial tissue， such as disorder of cell arrangement， cell shrinkage and cytoplasm staining. Compared with raw A. kusnezoffii group， serum contents of cTn-I and MB in raw A. kusnezoffii-T. chebula （1 ∶ 3， 1 ∶ 1， 3 ∶ 1） groups were decreased significantly （P＜0.05）， and there was no significant difference between the raw A. kusnezoffii-T. chebula （3 ∶ 1， 1 ∶ 1） groups and blank control group （P＞0.05）； myocardial pathological changes were improved to varying degrees. The structure of myocardial tissue in raw A. kusnezoffii-T. chebula （3 ∶ 1） groups were similar to blank control group. In the mechanism investigation experiment under the condition of different concentrations， plasma protein binding rates of 3 kinds of aconitine with normal human plasma were about 30％， without statistical significance （P＞0.05） and significant concentration-dependent manner. After adding tannic acid， plasma protein binding rate of 3 kinds of aconitine in A. kusnezoffii was decreased to different extent； when 3 kinds of aconitine were combined with tannic acid in the ratio of 1 ∶ 0.1， 1 ∶ 0.075 and 1 ∶ 0.5， the plasma protein binding rate decreased significantly （P＜0.05）， in proportion-dependent manner. CONCLUSIONS： Compatible use of raw A. kusnezoffii-T. chebula （3 ∶ 1） show that best detoxification effect on A. kusnezoffii-induced cardiotoxicity. Under this compatibility ratio， the plasma protein binding rate of 3 kinds of aconitine in A. kusnezoffii with normal human plasma is relatively high and the free drug concentration is relatively low.

Binding characteristics of plasma protein in active parts of Daidai lipid-lowering flavonoid extract / 中国中药杂志

To study the binding capacity of active ingredients of Daidai lipid-lowering flavonoid extract and plasma protein,investigate the ways to improve the traditional formula for calculating protein binding rates based on ultrafiltration,and increase the stability and reliability of the experimental results. UPLC-MS/MS was used to establish a quantitative analysis method for simultaneous determination of active ingredients( neohesperidin and narngin) in ultrafiltrate. The protein binding rates were calculated by the traditional ultrafiltration formula. The correction factors( F) were introduced later,and the binding rates calculated with the correction factors were compared with those without the correction factors. The binding capacity of the extract and plasma protein was evaluated. The quantitative analysis method established by UPLC-MS/MS had a good specificity. The standard curve and linear range,method accuracy,precision and lower limit of quantitation all met the requirements. The method met the requirement for quantitative detection of the active ingredients in ultrafiltrate after the rat plasma was filtrated in the ultrafiltration tube. Under the experimental conditions,the binding rates of both active ingredients( neohesperidin and narngin) were higher than 90%. The active ingredients and rat plasma protein were bound in a concentration-dependent manner,with statistically significant differences( P<0. 01). There was no statistically significant difference between the protein binding abilities of the two active ingredients with rat plasma protein. Therefore,the active ingredients of Daidai lipid-lowering flavonoid extract had a relatively strong binding strength with rat plasma protein,and they were bound in a concentration-dependent manner. Additionally,when calculating protein binding rates by the traditional ultrafiltration formula,the correction factors could be introduced to effectively reflect the errors of multiple ingredient groups in traditional Chinese medicine extracts.This correction method could provide a reference thinking and practical reference for the improvement of the determination method of the traditional Chinese medicine plasma protein binding ability based on ultrafiltration.

Determination of Rat Plasma Protein Binding Rate of Mesaconine by UPLC-MS/MS / 中国药学杂志

OBJECTIVE: To establish an analytical method for determination of mesaconine in rat plasma or dialysate, and study the rat plasma protein binding rate of mesaconine. METHODS: The equilibrium dialysis method was applied to determine the in vitro plasma protein binding rate of mesaconine. A UPLC-MS/MS method was established to determine mesaconine in the intra- and extradialysis samples and then the plasma protein binding rate was calculated. RESULTS: The specificity of the established UPLC-MS/MS method was very good. The calibration curve of mesaconine had good linearity over the range of 0.156 3 - 10 μg•mL-1. The intra-day and inter-day precisions and recovery met the requirements of methodology. The plasma protein binding rates of mesaconine were 18.73%, 20.20%, 26.59%, and 23.68% at the concentrations of 0.2, 0.5, 2.0, and 5.0 μg•mL-1, respectively. CONCLUSION: The method is simple, accurate and sensitive, and can meet the requirement for analysis method of biological samples. Mesaconine has a low rat plasma protein binding rate.

Plasma Protein Binding Characteristics of Neopanaxadiol in Rats by UPLC-MS/MS / 中国药学杂志

OBJECTIVE: To develop an UPLC-MS/MS method for the determination of neopanaxadiol(NPD) in rat plasma sample, and to investigate plasma protein binding rate of NPD in rats. METHODS: Under three different concentrations, equilibrium dialysis method was utilized to imitate the binding process between NPD and plasma protein. The concentration of NPD in and out of the dialysis membrane was determined by UPLC-MS/MS and the plasma protein binding rate of NPD were calculated. RESULTS: Excellent linearity was found between 0.05-8 μg·mL -1. Intra- and inter-day precision values (RSD) of QC samples were both below 15% and the extraction recoveries of NPD from biological matrices were better than 79.37%. The plasma protein binding rates of NPD were (86.55±4.50)%, (76.50±2.61)% and (78.25±1.32)% at low, middle and high concentrations, respectively. There was no significant difference among three concentrations. CONCLUSION: These results indicate the high plasma protein binding rates of NPD in plasma in combination mode.

Effect of Capsaicin on the Plasma Protein Binding Rate of Simvastatin Determined by Ultrafiltration / 中国药学杂志

OBJECTIVE: To investigate the effect of capsaicin on the binding rates of simvastatin with rats and healthy subjects plasma. METHODS: The plasma protein binding rates of simvastatin in the presence or absence of capsaicin were determined by ultrafiltration combined with liquid chromatography-mass spectrometry (LC-MS/MS). RESULTS: The binding rates of simvastatin (0.2, 0.5, 1 μg·mL-1) were (97.73±0.24)%, (96.75±2.58)%, and (96.23±0.81)% in rat plasma and (97.05±1.74)%, (97.68±0.65)%, and (97.20±1.00)% in human plasma, respectively. In the presence of capsaicin (1 μg·mL-1), the plasma protein binding rates of simvastatin decreased to (93.97±0.96)%, (92.76±1.89)%, (92.05±0.58)% and (91.71±2.51)%, (91.73±1.88)%, (91.41±2.48)%, while the unbound drug concentration increased by 1.66, 1.23, 1.11 fold and 1.81, 2.56, 2.07 fold, respectively. CONCLUSION: Capsaicin could significantly decrease the plasma protein binding rate of simvastatin and increase its free drug concentration (P<0.01). When the clinical use of simvastatin, attention should be paid to the effect of drugs/ food containing capsaicin on its plasma protein binding rate.

Correlation study on in vivo pharmacokinetics and anti-oxidation of Guhong Injection in cerebral ischemia reperfusion injury model of rats / 中草药

Objective: To investigate the in vivo pharmacokinetic progress of hydroxysafflor yellow A (HSYA) from Guhong Injection in cerebal ischemia reperfusion (I/R) injury of rats and the correlation with its anti-oxidation effect. Methods: The equilibrium dialysis method was carried out to determine the plasma protein binding rates of HYSA and HSYA in Guhong Injection. Middle cerebral artery occlusion (MCAO) model rats were iv injected HYSA (4 mg/kg) or Guhong Injection (10 mL/kg). The HPLC method was adopted to determine the plasma concentration of HYSA at different time points to draw the drug-time curve. Meanwhile, glutathione peroxidase (GSH-Px) and lactate dehydrogenase (LDH) activities were determined to draw the time-effect curve. Furthermore, the relationship between pharmacokinetics and pharmacodynamics was analyzed. Results: At the concentration of 2.5, 10, and 25 mg/L, the p plasma rotein binding rates of HYSA were 77.96%, 73.54%, and 76.13%, whereas the plasma protein binding rates of HYSA from Guhong Injection were 68.21%, 58.22%, and 63.17%, respectively. A good linear relationship of HYSA was obtained in the range of 0.01-50 mg/L, the mean recoveries were (99.94 ± 2.82)%, (104.16 ± 1.41)%, and (99.74 ± 1.06)% for low, middle, and high concentration of the samples, respectively. Compared with HYSA group, Guhong Injection significantly increased the AUC of HYSA and decreased the MRT and Vz of HYSA. Furthermore, Guhong Injection increased the content of GSH-Px and decreased the content of LDH. The plasma concentration of HYSA is positively related to the GSH-Px activity and negatively related to the LDH activity. Conclusion: The results indicate that HYSA has the moderate plasma protein binding rate. Compared with HYSA group, the plasma protein binding rate in Guhong Injection group is reduced. Guhong Injection could increase the bioavailability of HYSA to enhance therapeutic efficacy and increase the distribution of HYSA in ischemia rats. Guhong Injection has better anti-oxidant effect, as well as more significant protective effect against cerebral I/R injury than HYSA.

Plasma protein binding characteristics of decapeptide in several species / 中国药学杂志

OBJECTIVE: To study the plasma protein binding rate of decapeptide in several species. METHODS: Ultrafiltration was employed to separate the free and bound decapeptide, acetonitrile was used to precipitate protein, then the plasma concentration of decapeptide by HPLC-MS/MS. RESULTS: The plasma protein binding rates of decapeptide at low, middle and high concentrations (50.0, 100.0, and 800.0 ng·mL-1) were (95.9±1.1)%, (97.40±0.7)% and (94.9±0.6)% in SD rats,(96.8±0.8)%, (97.8±0.2)% and (96.9±0.5)% in Beagle dogs, and (97.3±1.0)%, (98.6±0.2 )% and (96.2±0.9)% in humans, respectively. The average plasma protein binding rate was 96.2% after subcutaneous administration at 200 μg·kg-1 in SD rats. And the average plasma protein binding rate was 97.1% after intramuscular injection at 320 μg·kg-1 in Beagle dogs. CONCLUSION: Decapeptide has potent binding ability to plasma protein in several species. The plasma protein binding rate of decapeptide is independent of its plasma concentrations.

Determination on Human Plasma Protein Binding Rate of Ginkgolide A, B and K in Diterpene Ginkgolides Meglumine Injection / 世界科学技术-中医药现代化

This paper was aimed to study the human plasma protein binding rate of diterpene ginkgolides meglumine injection.The equilibrium dialysis was used to determine the human plasma protein binding rate of ginkgolide A (GA),ginkgolide B (GB) and ginkgolide K (GK) in diterpene ginkgolides meglumine injection.The LC-MS/MS method was used for the content determination of ginkgolides.And then,the plasma protein binding rate was calculated.The results showed that there was no interference from other ingredients for the determination of ginkgolides.The calibration curve of the analytes was in good linearity in certain range of contents.The precision and stability of the analytes met the methodology requirements.After 8 h incubation,the human plasma protein binding rate of GA,GB and GK achieved balance.The human plasma protein binding rate of GA (0.34,1.70 and 8.51μg·mL-1) was 84.03%-88.11%; the human plasma protein binding rate of GB (0.62,3.09 and 15.5μg·mL-1) was 41.21%-53.56%; the human plasma protein binding rate of GK (0.04,0.20 and 1.01μg·mL-1) was 45.24%-59.59%.It was concluded that the method was simple,rapid and sensitive,which met the analysis requirement for biological samples.GA had a high plasma protein binding rate; GB and GK had medium plasma protein binding rate.

Assay of in Vitro Plasma Protein Binding Rate of Mangiferin in Rats / 中国药房

OBJECTIVE:To study the assay method of in vitro plasma protein binding rate of mangiferin in rats.METHODS:The plasma samples which were added with internal standard(rutin)were deproteinized with acetonitrile and the supernatant was assayed by HPLC.The equilibrium dialysis was carried out to determine the plasma protein binding rate of mangiferin.RESULTS:The plasma protein binding rates of mangiferin at low,middle and high concentrations were(50.0?1.9)%,(45.2?2.0)% and(45.9?2.1)%,respectively.CONCLUSION:This assay method is sensitive,reproducible and simple,and it meets the requirement of analysis.