Tissue distribution of Qingfei Paidu Decoction based on HPLC-MS/MS / 中国中药杂志

The tissue distribution of Qingfei Paidu Decoction was studied by HPLC-MS/MS in vivo. Hypersil GOLD C_(18) column(2.1 mm×50 mm, 1.9 μm) was used for gradient elution with acetonitrile as the mobile phase A and 0.1% formic acid solution as the mobile phase B. High-resolution liquid chromatography-mass spectrometry in both positive and negative ion scanning mode and multiple response monitoring(MRM) mode was employed to analyze the behaviors of the active components of Qingfei Paidu Decoction in diffe-rent tissues. The results showed that 19, 9, 17, 14, 22, 19, 24, and 2 compounds were detected in plasma, heart, liver, spleen, lung, kidney, large intestine, and brain, respectively. The compounds belonged to 8 groups, covering 14 herbs in the prescription. After administration with Qingfei Paidu Decoction, the compounds were rapidly distributed in various tissues, especially in the lung, liver, large intestine, and kidney. The majority of the compounds displayed secondary distribution. This study comprehensively analyzed the distribution rules of the main active components in Qingfei Paidu Decoction and provided a basis for the clinical application.

Pharmacokinetics and tissue distribution of four alkaloids in Ermiao Pills and Sanmiao Pills in normal and arthritic model rats / 中国中药杂志

This work aimed to investigate the differences of pharmacokinetics and tissue distribution of four alkaloids in Ermiao Pills and Sanmiao Pills in normal and arthritic model rats. The rat model of arthritis was established by injecting Freund's complete adjuvant, and ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) in the positive ion multiple reaction monitoring(MRM) mode was used for the determination of four alkaloids in plasma and tissues of normal and arthritic rats after administration of Ermiao Pills and Sanmiao Pills, respectively. The differences in pharmacokinetics and tissue distribution of the four active components were compared, and the effect of Achyranthis Bidentatae Radix on the major components of Sanmiao Pills was explored. This study established an UPLC-MS/MS for simultaneous determination of four alkaloids, and the specificity, linearity, accuracy, precision, and stability of this method all met the requirements. Pharmacokinetics study found that as compared with normal rats, the AUC and C_(max) of phellodendrine, magnoflorine, berberine and palmatine in model rats were significantly decreased after administration of Ermiao Pills, the clearance rate CL/F was significantly increased, and the distribution and tissue/plasma concentration ratio of the four alkaloids in the liver, kidney, and joint were significantly reduced. Achyranthis Bidentatae Radix increased the AUC of phellodendrine, berberine, and palmatine, reduced the clearance rate, and significantly increased the distribution of the four alkaloids in the liver, kidney, and joints in arthritic rats. However, it had no significant effect on the pharmacokinetics and tissue distribution of the four alkaloids in normal rats. These results suggest that Achyranthis Bidentatae Radix may play a guiding role in meridian through increasing the tissue distribution of effective components in Sanmiao Pills under arthritis states.

Comparative stomach tissue distribution profiles of four major bio-active components of Radix Astragali in normal and gastric ulcer mice

Numerous studies have demonstrated that Radix Astragali can inhibit gastric ulcers in mice. Anhydrous ethanol (0.01 mL/g) administered to mice by intragastric infusion can induce gastric ulcer injury. This study was performed to compare the stomach tissue distribution profiles of four major bioactive constituents of Radix Astragali(calycosin-7-O-ß-d-glucoside, calycosin, ononin and formononetin) after oral administration of extract of Radix Astragali (ERA)in normal and gastric ulcer mice. The abundance of Radix Astragali constituents was determined using an ultra-pressure liquid chromatograph with a photodiode array detector (UPLC-PDA), after which histograms were drawn. In comparison with normal mice, the contents of calycosin- 7-O-ß-d-glucoside, calycosin, ononin and formononetin in the stomach tissue samples of gastric ulcer mice showed significant differences at the selected time points (P < 0.05).The abundance of each of the four tested constituents in the normal groups was higher than that of the gastric ulcer groups. This study provides an empirical foundation for future studies focused on developing clinical applications of Radix Astragali

Pharmacokinetic behavior and brain tissue distribution of paeoniflorin combined with normal and toxic doses of strychnine in rats after percutaneous administration / 中国中药杂志

This study aims to establish a rapid and sensitive UPLC-MS/MS method for simultaneously determining the content of strychnine and paeoniflorin in plasma and brain tissue of rats, and compare the pharmacokinetic behavior and brain tissue distribution of paeoniflorin combined with normal and toxic doses of strychnine in rats after percutaneous administration. Compared with those in the toxic-dose strychnine group, the AUC_(0-t), AUC_(0-∞), and C_(max) of strychnine decreased by 51.51%, 45.68%, and 46.03%, respectively(P<0.01), and the corresponding values of paeoniflorin increased by 91.41%, 102.31%, and 169.32%, respectively(P<0.01), in the compatibility group. Compared with the normal-dose strychnine group, the compatibility group showed insignificantly decreased C_(max), AUC_(0-t), and AUC_(0-∞) of strychnine, increased C_(max) and T_(max) of paeoniflorin(P<0.01), 66.88% increase in AUC_(0-t), and 70.55% increase in AUC_(0-∞) of paeoniflorin. In addition, the brain tissue concentration of strychnine decreased and that of paeoniflorin increased after compatibility. The combination of paeoniflorin with normal dose and toxic dose of strychnine can inhibit the percutaneous absorption of strychnine, and greatly promote the percutaneous penetration of paeoniflorin, whereas the interaction mechanism remains to be explored. The UPLC-MS/MS method established in this study is easy to operate and has good precision. It is suitable for in vivo study of pharmacokinetic behavior and brain tissue distribution of paeoniflorin and strychnine after percutaneous administration in rats, which provides reference for the safe and rational clinical use of strychnine and the combined use of drugs, and lays a solid foundation for the development of external preparations containing Strychni Semen.

Study on patterns and characteristics of in vivo tissue distribution of anti-inflammatory extract of Tetrastigma hemsleyanum aerial part in healthy and inflammatory pathological model rats / 中国中药杂志

The concentrations of seven anti-inflammatory components in blood and tissues were determined by UPLC-MS/MS after oral administration of Tetrastigma hemsleyanum aerial part(THAA) in healthy and inflammatory pathological model rats. The determination was carried out by using positive and negative ion switching technique, and multiple reaction monitoring(MRM) mode. The tissue distributions of the seven components in different physiological states were compared, and the patterns and characteristics of the effective components of THAA were studied. The results revealed that the seven effective components have large drug-time-curve areas(AUC) in heart, brain, small intestine, and stomach in both normal rats and inflammatory pathological model rats. This suggests that the anti-inflammatory effective component groups in THAA extract can all penetrate the blood-brain barrier, and have a large distribution area in gastrointestinal tract. It is inferred that gastrointestinal reabsorption may be one of the causes of the bimodal distribution of the drug-time curve of the drug blood distribution graph. As compared to normal rats, the effective component groups in THAA extract have higher drug-time curve area(AUC) in heart, brain, small intestine, stomach, liver, spleen, lung, kidney, and muscle of inflammatory pathological model rats. Among them, the effective component groups have the largest distribution area in heart, brain, small intestine, and stomach. This suggests that the binding force of organ tissues and drugs in the body may change under pathological conditions. It is speculated that the heart, brain, small intestine, and stomach may be the target tissues of THAA to produce anti-inflammatory effect. The retention times of THAA effective component groups in various organ tissues of rats in different physiological states are all relatively short, and do not have much difference. This suggests that no effective component accumulates in body, and that the pathological state of inflammation does not affect the onset times of the effective component groups. This experiment elucidates the patterns and characteristics of the in vivo target-effecting tissue distribution of THAA anti-inflammatory extract, and provides an experimental basis for clinical treatment.

Farmacocinética da micafungina em pacientes tratados com oxigenação por membrana extracorpórea: um estudo observacional prospectivo / Pharmacokinetics of micafungin in patients treated with extracorporeal membrane oxygenation: an observational prospective study

RESUMO Objetivo: Determinar os níveis plasmáticos e o comportamento farmacocinético da micafungina em pacientes tratados com oxigenação por membrana extracorpórea. Métodos: As amostras foram colhidas por meio de pontos de acesso antes e depois da membrana, em dois hospitais espanhóis de nível terciário. Os momentos para o cálculo das curvas farmacocinéticas foram antes da administração do fármaco, e 1, 3, 5, 8, 18 e 24 horas após o início da infusão nos dias 1 e 4 de tratamento. Calcularam-se a área sob a curva, a depuração do fármaco, o volume de distribuição e a meia-vida plasmática por meio de análise farmacocinética não compartimental. Resultados: Os valores farmacocinéticos analisados no primeiro e quarto dias de tratamento não mostram qualquer diferença de concentração entre amostras colhidas antes da membrana e após a membrana, e o comportamento farmacocinético foi similar na vigência de diferentes falências de órgãos. A área sob a curva antes da membrana no dia 1 foi de 62,1 (IC95% 52,8 - 73,4) e a área sob a curva após a membrana nesse mesmo dia foi de 63,4 (IC95% 52,4 - 76,7), com p = 0,625. A área sob a curva antes da membrana no dia 4 foi de 102,4 (IC95% 84,7 - 142,8), enquanto a área sob a curva após a membrana nesse mesmo dia foi de 100,9 (IC95% 78,2 - 138,8), com p = 0,843. Conclusão: Os parâmetros farmacocinéticos da micafungina não foram alterados significantemente.

ABSTRACT Objective: To determine micafungin plasma levels and pharmacokinetic behavior in patients treated with extracorporeal membrane oxygenation. Methods: The samples were taken through an access point before and after the membrane in two tertiary hospitals in Spain. The times for the calculation of pharmacokinetic curves were before the administration of the drug and 1, 3, 5, 8, 18 and 24 hours after the beginning of the infusion on days one and four. The area under the curve, drug clearance, volume of distribution and plasma half-life time with a noncompartmental pharmacokinetic data analysis were calculated. Results: The pharmacokinetics of the values analyzed on the first and fourth day of treatment did not show any concentration difference between the samples taken before the membrane (Cin) and those taken after the membrane (Cout), and the pharmacokinetic behavior was similar with different organ failures. The area under the curve (AUC) before the membrane on day 1 was 62.1 (95%CI 52.8 - 73.4) and the AUC after the membrane on this day was 63.4 (95%CI 52.4 - 76.7), p = 0.625. The AUC before the membrane on day 4 was 102.4 (95%CI 84.7 - 142.8) and the AUC was 100.9 (95%CI 78.2 - 138.8), p = 0.843. Conclusion: The pharmacokinetic parameters of micafungin were not significantly altered.

Mesenchymal stem cell therapy in acute kidney injury (AKI): review and perspectives

SUMMARY INTRODUCTION: Acute kidney injury (AKI) is highly prevalent today. It has a multifactorial aetiology and affects people of all ages, genders and ethnicities. Its treatment is essentially supportive of renal function substitution, so new treatment alternatives such as mesenchymal stem cell therapy (MSCs) should be investigated. METHODS: This review encompasses our understanding of the main mechanisms of action of MSCs in preclinical models of AKI by renal pedicle clamping ischemia-reperfusion, chemotherapy (cisplatin) and kidney transplantation in small and large animals, as well as outcomes in patients with AKI due to ischemia and kidney transplantation. RESULTS: Cellular therapy with MSCs has benefits in preclinical studies of AKI through various mechanisms, such as anti-inflammatory, antiapoptotic, oxidative anti-stress, antifibrotic, immunomodulatory and proangiogenic. In humans, MSC therapy is safe and effective. However, the challenges of MSC cell therapy include investigating protocols about the optimal dose of these cells, the route and frequency of appropriate administration, and the design of further biodistribution studies over a long follow-up period. In addition, a better understanding of molecular signalling and cellular interactions in the microenvironment of each organ and tissue is needed in order to define the best time to administer MSCs. Another challenge would be to mitigate the heterogeneity of the profile of cultured MSCs through preconditioning approaches. CONCLUSIONS: Cellular therapy with MSCs is very promising and should be part of the treatment of AKI patients in combination with other approaches already available, helping to accelerate recovery and/or slow the progression to chronic kidney disease. Randomized, multicentre controlled studies are needed to develop robust protocols that validate population-based cell therapy with MSCs.

Chemical profiling and tissue distribution study of Jingyin Granules in rats using UHPLC-Q-Exactive Orbitrap HR-MS / 中国中药杂志

In this study, the chemical profiling of Jingyin Granules and the tissue distribution of nine major constituents in this Chinese medicine were performed after oral administration of Jingyin Granules to rats, by using UHPLC-Q-Exactive Orbitrap HR-MS. An Acquity UPLC BEH C_(18) chromatographic column(2.1 mm×100 mm, 1.7 μm) was used as solid phase, while the mobile phase was methanol and 0.1% formic acid water for gradient elution. The major constituents in this Chinese medicine were quickly and accurately identified, via comparison with the retention times and MS/MS spectra of the standards. A total of 106 chemicals were identified from Jingyin Granules, including 24 kinds of organic acids, 47 kinds of flavonoids, 10 kinds of iridoids, and 21 kinds of saponins and 4 kinds of other compounds. After oral administered Jingyin Granules to rats, 48, 30, 25, 23, 45, 34, 39, 26, 19 prototype compounds were identified in serum, heart, liver, spleen, lung, kidney, brain, fat, and testicles, respectively. Meanwhile, an LC-MS based analytical method was established for simultaneous determination of chlorogenic acid, swertiamarin, caffeic acid, sweroside, liquiritin, prim-O-glucosylcimifugin, arctiin, 5-O-methylvisammioside and arctigenin in biological samples. The tissue distribution(serum, liver and lung) of these nine aim constituents in rats after oral administration of Jingyin Granules were investigated. It was found that these nine constituents could be quickly absorbed into circulation system and then distributed to liver and lung tissues. Except arctigenin, the exposure of other eight aim constituents to serum and lung was peaked at 1 h. At 1 h, the exposure of these components to lung tissue were ranked as follows: swertiamarin [(75 191.0±3 483.21) ng·g~(-1)]>arctiin [(2 716.5±36.06) ng·g~(-1)]>5-O-methylvisammioside [(585.1±0.71) ng·g~(-1)]>arctigenin [(437.45±3.18) ng·g~(-1)]>chlorogenic acid [(308.1±5.66) ng·g~(-1)]>prim-O-glucosylcimifugin [(211.35±2.19) ng·g~(-1)]>sweroside [(184.3±9.05) ng·g~(-1)]>caffeic acid [(175.95±2.05) ng·g~(-1)]>liquiritin [(174.78±153.34) ng·g~(-1)]. In summary, an UHPLC-Q-Exactive Orbitrap HR-MS method has been established for rapid and accurate identification of the constituents in Jingyin Granules, while the tissue distribution of nine major absorpted constituents were investigated in rats following oral administration of Jingyin Granules. These findings provided key information and guidance for further studies on pharmacodynamic substances and clinical applications of Jingyin Granules.

Asma: uso adecuado de dispositivos para inhalación / Asthma: correct use of inhalation drug-delivery devices

Resumen La terapia inhalada se considera la piedra angular del manejo del asma. Sin embargo, a pesar de ser la forma ideal de administración de estos medicamentos, solamente el 70% de los pacientes cumple el tratamiento adecuadamente y sólo del 39 al 67% de los médicos conocen y pueden explicar de forma adecuada las distintas técnicas de inhalación. La terapia inhalada tiene características muy particulares. El depósito pulmonar de un medicamento inhalado a través del tracto respiratorio es más complejo que cuando se administra por vía oral, y varía dependiendo de varios factores, tanto inherentes al medicamento como a la forma de administrarlo. Para que la terapia inhalada sea exitosa, se requiere que se generen partículas del medicamento de un tamaño apropiado que penetren más allá de la orofaringe y la laringe, y que puedan depositarse en los pulmones. Existen múltiples dispositivos para la administración de medicamentos en la vía respiratoria baja. Cada uno ha probado tener una eficacia similar, siempre y cuando se utilicen con la técnica correcta. La decisión para su uso se realiza con base en la edad del paciente, la capacidad de coordinar entre la inhalación y la activación del dispositivo y la presencia de síntomas agudos. La elección del dispositivo a utilizar siempre deberá hacerse de forma conjunta, evaluando pros y contras de cada uno de los dispositivos y siempre de forma individualizada.

Abstract Inhaled therapy is considered the cornerstone of asthma treatment. However, despite being the ideal form of drug delivery, it is recognized that only 70% of patients have an adequate attachment to their treatment and only 39-67% of physicians can explain the optimal inhaler technique. Inhaled therapy has very specific characteristics. Pulmonary deposit of an inhaled medication through the respiratory tract is more complex than when administered orally and depends on several factors inherent to both the medication and the administration. For successful inhaled therapy, the drug needs to be converted into particles of an appropriate size, which can enter beyond the oropharynx and larynx, and be deposited in the lungs. There are multiple devices for the administration of drugs in the lower respiratory tract, each one with a similar efficacy as long as it is used with the correct technique. The decision of which device should be used is made based on the age of the patient, the ability to coordinate between the inhalation and activation of the device, and the presence of acute symptoms. The choice of the device must be evaluated individually.

Comparison among ACR1997, SLICC and the new EULAR/ACR classification criteria in childhood-onset systemic lupus erythematosus

Abstract Background: To date there are no specific classification criteria for childhood-onset systemic lupus erythematosus (cSLE). This study aims to compare the performance among the American College of Rheumatology (ACR) 1997, the Systemic Lupus International Collaborating Clinics criteria (SLICC) and the new European League Against Rheumatism (EULAR)/ACR criteria, in a cSLE cohort. Methods: We conducted a medical chart review study of cSLE cases and controls with defined rheumatic diseases, both ANA positive, to establish each ACR1997, SLICC and EULAR/ACR criterion fulfilled, at first visit and 1-year-follow-up. Results: Study population included 122 cSLE cases and 89 controls. At first visit, SLICC criteria had higher sensitivity than ACR 1997 (89.3% versus 70.5%, p < 0.001), but similar specificity (80.9% versus 83.2%, p = 0.791), however performance was not statistically different at 1-year-follow-up. SLICC better scored in specificity compared to EULAR/ACR score ≥ 10 at first visit (80.9% versus 67.4%, p = 0.008) and at 1-year (76.4% versus 58.4%, p = 0.001), although sensitivities were similar. EULAR/ACR criteria score ≥ 10 exhibited higher sensitivity than ACR 1997 (87.7% versus 70.5%, p < 0.001) at first visit, but comparable at 1-year, whereas specificity was lower at first visit (67.4% versus 83.2%, p = 0.004) and 1-year (58.4% versus 76.4%, p = 0.002). A EULAR/ACR score ≥ 13 against a score ≥ 10, resulted in higher specificity, positive predictive value, and cut-off point accuracy. Compared to SLICC, a EULAR/ACR score ≥ 13 resulted in lower sensitivity at first visit (76.2% versus 89.3%, p < 0.001) and 1-year (91% versus 97.5%, p = 0.008), but similar specificities at both assessments. When compared to ACR 1997, a EULAR/ACR total score ≥ 13, resulted in no differences in sensitivity and specificity at both observation periods. Conclusions: In this cSLE population, SLICC criteria better scored at first visit and 1-year-follow-up. The adoption of a EULAR/ACR total score ≥ 13 in this study, against the initially proposed ≥10 score, was most appropriate to classify cSLE. Further studies are necessary to address if SLICC criteria might allow fulfillment of cSLE classification earlier in disease course and may be more inclusive of cSLE subjects for clinical studies.

Effect of N-acetyl-L-cysteine on bioavailability and brain distribution of curcumin by nasal delivery / 中国中药杂志

Curcumin( Cur) is a natural active substance extracted from the roots or tubers of traditional Chinese medicinal materials. It has anti-inflammatory and anti-tumor activities on brain diseases. Due to the poor stability,low solubility,poor absorption and low bioavailability of curcumin,N-acetyl-L-cysteine( NAC) was used as an absorption enhancer and mixed with curcumin to improve the absorption of curcumin in the body. In this paper,curcumin was smashed by airflow pulverization,and Cur-NAC mixtures were prepared by being grinded with liquid. Then,the raw material and the product were analyzed by differential scanning calorimetry( DSC),X-ray diffraction( XRD) for structural characterization. The dissolution was determined by high performance liquid chromatography( HPLC) analysis. The characteristic peaks of the samples prepared by grinding method were similar to those of the raw materials,while the melting temperature and the accumulated dissolution degree were not significantly changed. The crystal forms of the products were not changed,and no new crystal form was formed after grinding. After the administration of intranasal powder,blood samples were collected from the orbit,while the whole brain tissues were removed from the skull and dissected into 10 anatomical regions. The concentrations of curcumin in these samples were determined by UPLC-MS/MS. The concentrations of curcumin in plasma and brain were compared at different time points. After intranasal administration of two drugs,it was found that the concentration of curcumin after sniffing up the mixtures in plasma was high,and the concentration of the drug in the olfactory bulb,hippocampus,and pons was increased significantly. Within 0. 083-0. 5 h,the olfactory bulb,piriform lobe and hippocampus remained high concentrations,the endodermis,striatum,hypothalamus and midbrain reached high concentrations within 1-3 h; and the cerebellum,pons and brain extension maintained relatively high concentrations within 3-7 h. The experiment showed that nasal administration of Cur-NAC mixtures can significantly improve the bioavailability of curcumin,and lead to significant differences in brain tissue distribution.

Bioinformatics and tissue distribution analysis of Tripterygium wilfordii CYP450 / 中国中药杂志

Cytochrome P450 family is a kind of biocatalyst widely existing in nature. It has many functions such as catalyzing the biosynthesis of plant secondary metabolites and regulating phytoremediation. Based on the analysis of proteome data of Tripterygium wilfordii,the CYP450 gene of T. wilfordii was preliminarily analyzed and predicted by various bioinformatics methods. The results showed that after the expression of T. wilfordii suspension cells was induced by methyl jasmonate,the proteomic data of T. wilfordii were obtained and analyzed,and 10 CYP450 proteins of T. wilfordii were finally screened out. By analyzing the phylogenetic tree constructed with CYP450 gene of Arabidopsis family,the 10 CYP450 proteins were clustered into 6 different CYP450 families. The physical and chemical properties of CYP450 proteins in different families were different. The secondary structure of CYP450 proteins was mainly composed of irregular curls. Eight subcellular localization results of CYP450 proteins were chloroplasts and the rest were plastids. Subsequently,the conserved domains( heme active sites) shared by CYP450 genes were found by analyzing the results of multiple sequence alignment. Finally,by analyzing the transcriptome data of T. wilfordii,the expression distribution of T. wilfordii in different tissues was preliminarily confirmed,which verified its correlation with the biosynthesis of active components of T. wilfordii,and provided important genetic resources for the analysis of biosynthesis pathway of active components of T. wilfordii.

Effect of type 2 diabetes mellitus on flavonoid pharmacokinetics and tissue distribution after oral administration of Radix Scutellaria extract in rats / 中国天然药物

Radix Scutellaria is widely applied to the treatment of diabetes mellitus in China. Its main bioactive constituents contain baicalin, wogonoside, oroxyloside, and their aglycones. To investigate the effect of type 2 diabetes mellitus on both pharmacokinetics and tissue distribution of these flavonoid compounds, the six flavonoids in plasma and tissues from the normal and type 2 diabetic rats after oral administration of Radix Scutellaria extract were simultaneously measured by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. The results showed that baicalin, wogonoside, and oroxyloside had higher C and AUC values (P < 0.05) in type 2 diabetic rats than that in normal rats and the tissue-distribution behaviors of the six flavonoid compounds in hearts, livers, spleens, lungs, kidneys, brains, pancreas, fat and muscle of the type 2 diabetic rats showed obviously differences from the normal rats (P < 0.05). In conclusion, the differences in the pharmacokinetics of oroxyloside and tissue distribution of the six flavanoids in Radix Scutellaria extract between diabetic and normal rats were found for the first time. The results from the present study provided a crucial basis for a better understanding of in vivo anti-diabetic mechanism of action of the six flavonoids from Radix Scutellaria.

In vivo imaging of breast tumors by a 99mTc radiolabeled probe targeting microRNA-155 in mice models / 北京大学学报(医学版)

OBJECTIVE@#MicroRNA-155 (miR-155) is significantly highly expressed in breast cancer, lung cancer, liver cancer and other malignant tumors. This study was to design and construct a radiolabeled probe targeting miR-155 for in vivo imaging in breast cancer.@*METHODS@#Anti-miR-155 oligonucleotide (AMO-155) was chemically synthesized with 2' OMe modification. Its 5' end was linked with acetyl amine group. After chelated with a bifunctional chelator NHS-MAG3, AMO-155 was radiolabeled with 99mTc using stannous chloride. The serum stability was evaluated at cellular level. In vivo imaging was performed in MCF-7 tumor bearing mice after the administration of 99mTc radiolabeled AMO-155 and scramble control probes, respectively. Furthermore, the blocked imaging of tumor bearing mice was obtained after the injection of unlabeled AMO-155 2 hours ahead. MCF-7 and MDA-MB-231 tumor bearing mice with different expression level of miR-155 were imaged, respectively. Quantitative real-time PCR (qRT-PCR) was used to identify the expression level of miR-155 in the bearing tumors.@*RESULTS@#99mTc-AMO-155 was prepared with high radiolabeled efficiency (97%), radiochemical purity (greater than 98%), and radioactive specific activity (3.75 GBq/μg). 99mTc-AMO-155 was stable in fresh human serum for 12 hours. After the administration via tail vein, 99mTc-AMO-155 displayed significant accumulation in MCF-7 bearing tumors with high expression level of miR-155, whereas 99mTc-control showed little accumulation. After blocked with unlabeled AMO-155, the tumor could not be visualized clearly after the administration of 99mTc-AMO-155. Furthermore, 99mTc-AMO-155 could show the differential expression of miR-155 in vivo. MCF-7 tumor was shown with significantly higher radioactive accumulation than MDA-MB-231, based on its higher expression level of miR-155, which was verified by qRT-PCR.@*CONCLUSION@#99mTc-labeled AMO-155 with chemical modification showed good serum stability and in vivo tumor targeting ability. This study provides a potential probe for in vivo imaging of breast cancer.

Effect of type 2 diabetes mellitus on flavonoid pharmacokinetics and tissue distribution after oral administration of Radix Scutellaria extract in rats / 中国天然药物

Radix Scutellaria is widely applied to the treatment of diabetes mellitus in China. Its main bioactive constituents contain baicalin, wogonoside, oroxyloside, and their aglycones. To investigate the effect of type 2 diabetes mellitus on both pharmacokinetics and tissue distribution of these flavonoid compounds, the six flavonoids in plasma and tissues from the normal and type 2 diabetic rats after oral administration of Radix Scutellaria extract were simultaneously measured by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. The results showed that baicalin, wogonoside, and oroxyloside had higher C and AUC values (P < 0.05) in type 2 diabetic rats than that in normal rats and the tissue-distribution behaviors of the six flavonoid compounds in hearts, livers, spleens, lungs, kidneys, brains, pancreas, fat and muscle of the type 2 diabetic rats showed obviously differences from the normal rats (P < 0.05). In conclusion, the differences in the pharmacokinetics of oroxyloside and tissue distribution of the six flavanoids in Radix Scutellaria extract between diabetic and normal rats were found for the first time. The results from the present study provided a crucial basis for a better understanding of in vivo anti-diabetic mechanism of action of the six flavonoids from Radix Scutellaria.

Tissue distribution of TPGS modified artesunate liposome and its metabolites in rats / 中国中药杂志

Artesunate, which is a widely used anti-malaria medicine, can be made into liposome to overcome its poor bioactivity. Its tissue distribution in rats may change with different dosage forms, which therefore shall be studied after ARS-TPGS-Lipo was injected. Based on this experiment, ARS-TPGS-Lipo and ARS-Lipo were prepared by thin-film hydration method. LC-MS/MS method was used to simultaneously determine ARS and DHA in rat tissues at different time points. The results showed that this method was suitable for the content analysis of ARS and DHA in biological samples. The distribution of ARS and DHA in ARS-TPGS-Lipo, ARS-Lipo and ARS groups were quite different. The content of ARS-TPGS-Lipo in liver was the highest, with significant differences.ARS and DHA contents in ARS group eliminated rapidly. ARS and DHA contents in ARS-Lipo group were higher in liver and spleen, while those in ARS-TPGS-Lipo group significantly increased only in liver (<0.05).

Pharmacokinetics of monoclonal antibodies and Fc-fusion proteins

There are many factors that can influence the pharmacokinetics (PK) of a mAb or Fc-fusion molecule with the primary determinant being FcRn-mediated recycling. Through Fab or Fc engineering, IgG-FcRn interaction can be used to generate a variety of therapeutic antibodies with significantly enhanced half-life or ability to remove unwanted antigen from circulation. Glycosylation of a mAb or Fc-fusion protein can have a significant impact on the PK of these molecules. mAb charge can be important and variants with pI values of 1-2 unit difference are likely to impact PK with lower pI values being favorable for a longer half-life. Most mAbs display target mediated drug disposition (TMDD), which can have significant consequences on the study designs of preclinical and clinical studies. The PK of mAb can also be influenced by anti-drug antibody (ADA) response and off-target binding, which require careful consideration during the discovery stage. mAbs are primarily absorbed through the lymphatics via convection and can be conveniently administered by the subcutaneous (sc) route in large doses/volumes with co-formulation of hyaluronidase. The human PK of a mAb can be reasonably estimated using cynomolgus monkey data and allometric scaling methods.

Long-circulating and target-specific distributions of cyanine 5.5-labeled hyaluronic acid nanoparticles in mouse organs during 28 days after a single administration / 대한수의학회지

Although hyaluronic acid (HA) has been developed as a nanoparticle (NP; 320–400 nm) for a drug delivery system, the tissue targeting efficacy and the pharmacokinetics of HA-NPs are not yet fully understood. After a dose of 5 mg/kg of cyanine 5.5-labeled HA-NPs or HA-polymers was intravenously administrated into mice, the fluorescence was measured from 0.5 h to 28 days. The HA-NPs fluorescence was generally stronger than that of HA-polymers, which was maintained at a high level over 7 days in vivo, after which it gradually decreased. Upon ex vivo imaging, liver, spleen, kidney, lung, testis and sublingual gland fluorescences were much higher than that of other organs. The fluorescence of HA-NPs in the liver, spleen and kidney was highest at 30 min, where it was generally maintained until 4 h, while it drastically decreased at 1 day. However, the fluorescence in the liver and spleen increased sharply at 7 days relative to 3 days, then decreased drastically at 14 days. Conversely, the fluorescence of HA-polymers in the lymph node was higher than that of HA-NPs. The results presented herein may have important clinical implications regarding the safety of as self-assembled HA-NPs, which can be widely used in biomedical applications.

Comparison of T-2 Toxin and HT-2 Toxin Distributed in the Skeletal System with That in Other Tissues of Rats by Acute Toxicity Test / 生物医学与环境科学（英文）

Twelve healthy rats were divided into the T-2 toxin group receiving gavage of 1 mg/kg T-2 toxin and the control group receiving gavage of normal saline. Total relative concentrations of T-2 toxin and HT-2 toxin in the skeletal system (thighbone, knee joints, and costal cartilage) were significantly higher than those in the heart, liver, and kidneys (P < 0.05). The relative concentrations of T-2 toxin and HT-2 toxin in the skeletal system (thighbone and costal cartilage) were also significantly higher than those in the heart, liver, and kidneys. The rats administered T-2 toxin showed rapid metabolism compared with that in rats administered HT-2 toxin, and the metabolic conversion rates in the different tissues were 68.20%-90.70%.

Prediction of pharmacokinetics and drug-drug interaction potential using physiologically based pharmacokinetic (PBPK) modeling approach: A case study of caffeine and ciprofloxacin

Over the last decade, physiologically based pharmacokinetics (PBPK) application has been extended significantly not only to predicting preclinical/human PK but also to evaluating the drug-drug interaction (DDI) liability at the drug discovery or development stage. Herein, we describe a case study to illustrate the use of PBPK approach in predicting human PK as well as DDI using in silico, in vivo and in vitro derived parameters. This case was composed of five steps such as: simulation, verification, understanding of parameter sensitivity, optimization of the parameter and final evaluation. Caffeine and ciprofloxacin were used as tool compounds to demonstrate the “fit for purpose” application of PBPK modeling and simulation for this study. Compared to caffeine, the PBPK modeling for ciprofloxacin was challenging due to several factors including solubility, permeability, clearance and tissue distribution etc. Therefore, intensive parameter sensitivity analysis (PSA) was conducted to optimize the PBPK model for ciprofloxacin. Overall, the increase in C(max) of caffeine by ciprofloxacin was not significant. However, the increase in AUC was observed and was proportional to the administered dose of ciprofloxacin. The predicted DDI and PK results were comparable to observed clinical data published in the literatures. This approach would be helpful in identifying potential key factors that could lead to significant impact on PBPK modeling and simulation for challenging compounds.